WorldWideScience

Sample records for acid decarboxylase expression

  1. Dynamic regulation of glutamic acid decarboxylase 65 gene expression in rat testis

    Institute of Scientific and Technical Information of China (English)

    Haixiong Liu; Shifeng Li; Yunbin Zhang; Yuanchang Yan; Yiping Li

    2009-01-01

    Glutamate decarboxylase 65 (GAD65) produces γ-amino-butyric acid,the main inhibitory neurotransmitter in adult mammalian brain.Previous experiments,per-formed in brain,showed that GAD65 gene possesses two TATA-less promoters,although the significance is unknown.Here,by rapid amplification of cDNA ends method,two distinct GAD65 mRNA isoforms transcribed from two independent clusters of transcription start sites were identified in post-natal rat testis.RT-PCR results revealed that the two mRNA isoforms had distinct expression patterns during post-natal testis maturation,suggesting that GAD65 gene expression was regulated by alternative promoters at the transcription level.By using GAD65-speciflc antibodies,western blotting analysis showed that the 58-kDa GAD65,N-terminal 69 amino acids truncated form of full-length GAD65 protein,was developmentally expressed during post-natal testis matu-ration,suggesting that GAD65 gene expression in testis may also be regulated by post-translational processing.Confocal immunofluorescence microscopy revealed that GAD65 protein was presented in Leydig cells of Day 1 testis,primary spermatocytes and spermatids of post-natal of Day 90 testis.The above results suggested that GAD65 gene expression is dynamically regulated at mul-tiple levels during post-natal testis maturation.

  2. Glutamic acid decarboxylase 67 expression by a distinct population of mouse vestibular supporting cells

    Directory of Open Access Journals (Sweden)

    Giancarlo eRusso

    2014-12-01

    Full Text Available The function of the enzyme glutamate decarboxylase (GAD is to convert glutamate in -aminobutyric acid (GABA.GAD exists as two major isoforms, termed GAD65 and GAD67,.that are usually expressed in GABA-containing neurons in the central nervous system. GAD65 has been proposed to be associated with GABA exocytosis whereas GAD67 with GABA metabolism. In the present immunofluorescence study, we have investigated the presence of the two GAD isoforms in the semicircular canal cristae of wild type and GAD67-GFP knock-in mice. While no evidence for GAD65 expression was found, GAD67 was detected in a distinct population of peripherally-located supporting cells, but not in hair cells or in centrally-located supporting cells. GABA, on the other hand, was found in all supporting cells. The present result indicate that only a discrete population of supporting cells use GAD67 to synthesize GABA. This is the first report of a marker that allows to distinguish two populations of supporting cells in the vestibular epithelium. On the other hand, the lack of GABA and GAD enzymes in hair cells excludes its involvement in afferent transmission.

  3. Hippocampal interneurons expressing glutamic acid decarboxylase and calcium-binding proteins decrease with aging in Fischer 344 rats.

    Science.gov (United States)

    Shetty, A K; Turner, D A

    1998-05-04

    Aging leads to alterations in the function and plasticity of hippocampal circuitry in addition to behavioral changes. To identify critical alterations in the substrate for inhibitory circuitry as a function of aging, we evaluated the numbers of hippocampal interneurons that were positive for glutamic acid decarboxylase and those that expressed calcium-binding proteins (parvalbumin, calbindin, and calretinin) in young adult (4-5 months old) and aged (23-25 months old) male Fischer 344 rats. Both the overall interneuron population and specific subpopulations of interneurons demonstrated a commensurate decline in numbers throughout the hippocampus with aging. Interneurons positive for glutamic acid decarboxylase were significantly depleted in the stratum radiatum of CA1, the strata oriens, radiatum and pyramidale of CA3, the dentate molecular layer, and the dentate hilus. Parvalbumin interneurons showed significant reductions in the strata oriens and pyramidale of CA1, the stratum pyramidale of CA3, and the dentate hilus. The reductions in calbindin interneurons were more pronounced than other calcium-binding protein-positive interneurons and were highly significant in the strata oriens and radiatum of both CA1 and CA3 subfields and in the dentate hilus. Calretinin interneurons were decreased significantly in the strata oriens and radiatum of CA3, in the dentate granule cell and molecular layers, and in the dentate hilus. However, the relative ratio of parvalbumin-, calbindin-, and calretinin-positive interneurons compared with glutamic acid decarboxylase-positive interneurons remained constant with aging, suggesting actual loss of interneurons expressing calcium-binding proteins with age. This loss contrasts with the reported preservation of pyramidal neurons with aging in the hippocampus. Functional decreases in inhibitory drive throughout the hippocampus may occur due to this loss, particularly alterations in the processing of feed-forward information through the

  4. Characterization of striatal neurons expressing high levels of glutamic acid decarboxylase messenger RNA.

    Science.gov (United States)

    Chesselet, M F; Robbins, E

    1989-07-17

    Two types of labelled cells are detected in sections of rat and mouse striata processed for in situ hybridization histochemistry with 35S-radiolabelled RNA probes complementary to the messenger RNA (mRNA) encoding glutamic acid decarboxylase (GAD), the synthesis enzyme for gamma-aminobutyric acid (GABA): numerous lightly, and fewer very densely labelled neurons. In order to determine whether the densely labelled cells correspond to the striatal somatostatinergic neurons with which they share morphological characteristics, the presence of GAD mRNA was examined in brain sections processed successively for dihydronicotinamide adenine dinucleotide phosphate (NADPH) diaphorase histochemistry, a marker of striatal somatostatinergic neurons, and in situ hybridization histochemistry. In addition, the distribution of GABAergic interneurons was analyzed with regard to striatal compartments (striosomes) indicated by patches of dense opiate binding sites. The results show that NADPH diaphorase activity and GAD mRNA do not co-exist in striatal neurons. Furthermore, in contrast to the somatostatinergic neurons which are almost exclusively located in the extrastriosomal matrix, densely labelled GAD cells were present both in the striosomes and the matrix, further suggesting that GABAergic and somatostatinergic neurons form two distinct interneuronal systems in the striatum of rats and mice.

  5. Differential distribution of glutamic acid decarboxylase-65 and glutamic acid decarboxylase-67 messenger RNAs in the entopeduncular nucleus of the rat.

    Science.gov (United States)

    Yuan, P Q; Grånäs, C; Källström, L; Yu, J; Huhman, K; Larhammar, D; Albers, H E; Johnson, A E

    1997-05-01

    The entopeduncular nucleus is one of the major output nuclei of the basal ganglia, with topographically organized projections to both motor and limbic structures. Neurons of the entopeduncular nucleus use GABA as the principal transmitter, and glutamic acid decarboxylase (the GABA synthetic enzyme) is widely distributed throughout the region. Previous studies have shown that glutamate decarboxylase exists in two forms (glutamic acid decarboxylase-65 and glutamic acid decarboxylase-67), and that the messenger RNAs for these different enzymes are widely distributed in rat brain. The purpose of the present experiment was to describe the distribution of glutamic acid decarboxylase-65 and glutamic decarboxylase-67 messenger RNAs throughout the entopeduncular nucleus using recently developed oligodeoxynucleotide probes and in situ hybridization histochemical methods. In agreement with previous studies, northern analysis of rat brain poly(A)+ messenger RNA preparations showed that the glutamic acid decarboxylase-65 and glutamic acid decarboxylase-67 probes used in the present study hybridized to messenger RNAs of approximately 5.7 and 3.7 kb, respectively. Film autoradiographic analysis revealed large region-dependent, isoform-specific differences in the levels of expression of the two messenger RNAs, with glutamic acid decarboxylase-65 messenger RNA predominating in rostral and medial regions of the entopeduncular nucleus and glutamic acid decarboxylase-67 messenger RNA most abundant in the caudal region. Cellular analysis showed that these region-dependent differences in labelling were due to differences in the relative amounts of glutamic acid decarboxylase-65 and glutamic acid decarboxylase-67 messenger RNAs expressed per cell rather than the number of cells expressing each form of glutamic acid decarboxylase messenger RNA. The differences in the distribution of glutamic acid decarboxylase-65 and glutamic acid decarboxylase-67 messenger RNAs are closely related to the

  6. Expression of glutamic acid decarboxylase messenger RNA in rat medial preoptic area neurones during the oestrous cycle and after ovariectomy.

    Science.gov (United States)

    Herbison, A E; Augood, S J; McGowan, E M

    1992-08-01

    Evidence suggests that medial preoptic area (MPOA) neurones containing gamma-aminobutyric acid (GABA) are modulated directly by oestrogen. We have used an alkaline phosphatase-labelled antisense oligonucleotide probe to examine glutamic acid decarboxylase67 (GAD) mRNA expression within individual cells of the MPOA, diagonal band of Broca (DBB) and parietal cortex in rats killed at noon on each day of the oestrous cycle and after ovariectomy (n = 4-5). As a fall in extracellular GABA concentrations occurs in the MPOA on the afternoon of proestrus, the GAD67 mRNA content of cells was also examined in proestrous rats at 15:00h immediately prior to the preovulatory luteinising hormone (LH) surge. The MPOA was found to have an intermediate number of GAD67 mRNA-containing cells compared with the DBB and cortex (P less than 0.01) but expressed the lowest mean hybridisation signal (P less than 0.01). The parietal cortex had significantly fewer (P less than 0.01) GAD mRNA-containing cells than either the MPOA or DBB but these contained higher mean density of signal (P less than 0.01). The hybridisation signal for GAD mRNA was abolished by either ribonuclease pre-treatment or the use of excess non-labelled probe. No significant (P greater than 0.05) differences in GAD67 mRNA were detected in animals killed at noon throughout the oestrous cycle or after ovariectomy. On the afternoon of proestrus (15:00h) there was a significant 40% reduction in mean GAD67 mRNA content within cells of only the MPOA compared with noon (P less than 0.05). The numbers of cells in the MPOA expressing GAD67 mRNA were not significantly different.(ABSTRACT TRUNCATED AT 250 WORDS)

  7. Expression of glutamic acid decarboxylase and identification of GABAergic cells in the ischemic rat dentate gyrus

    DEFF Research Database (Denmark)

    Müller, Georg Johannes; Dogonowski, Anne-Marie; Finsen, Bente;

    2006-01-01

    We have investigated the glutamic acid dexcarboxylase (GAD) mRNA and protein isoforms as markers for ischemic loss of GABAergic neurons in the dentate hilus. Stereological counts of these neurons were performed in rats surviving 8 days after 10 min of transient forebrain ischemia, and in control...

  8. Expression of glutamic acid decarboxylase and identification of GABAergic cells in the ischemic rat dentate gyrus

    DEFF Research Database (Denmark)

    Müller, Georg Johannes; Dogonowski, Anne-Marie; Finsen, Bente;

    2006-01-01

    We have investigated the glutamic acid dexarboxylase (GAD) mRNA and protein isoforms as markers for ischemic loss of GABAergic neurons in the dentate hilus. Stereological counts of these neurons were performed in rats surviving 8 days after 10 min of transient forebrain ischemia, and in control...

  9. Molecular cloning, expression and in situ hybridization of rat brain glutamic acid decarboxylase messenger RNA.

    Science.gov (United States)

    Julien, J F; Legay, F; Dumas, S; Tappaz, M; Mallet, J

    1987-01-14

    A cDNA library was generated in the expression vector lambda GT11 from rat brain poly(A)+ RNAs and screened with a GAD antiserum. Two clones reacted positively. One of them was shown to express a GAD activity which was specifically trapped on anti-GAD immunogel and was inhibited by gamma-acetylenic-GABA. Blot hybridization analysis of RNAs from rat brain revealed a single 4 kilobases band. Preliminary in situ hybridizations showed numerous cells labelled by the GAD probe such as the Purkinje and stellate cells in the cerebellar cortex and the cells of the reticular thalamic nucleus.

  10. Differential expression of glutamic acid decarboxylase in rat and human islets

    DEFF Research Database (Denmark)

    Petersen, J S; Russel, S; Marshall, M O;

    1993-01-01

    The GABA synthesizing enzyme GAD is a prominent islet cell autoantigen in type I diabetes. The two forms of GAD (GAD64 and GAD67) are encoded by different genes in both rats and humans. By in situ hybridization analysis of rat and human pancreases, expression of both genes was detected in rat isl...

  11. Characteristic expression of γ-aminobutyric acid and glutamate decarboxylase in rat jejunum and its relation to differentiation of epithelial cells

    Institute of Scientific and Technical Information of China (English)

    Fang-Yu Wang; Masahito Watanabe; Ren-Min Zhu; Kentaro Maemura

    2004-01-01

    AIM: To investigate the expression between γ-aminobutyric acid (GABA) and glutamate decarboxylase and its relation with differentiation and maturation of jejunal epithelial cells in rat jejunum.METHODS: Immunohistochemical expression of GABA and glutamate decarboxylase (GAD, including two isoforms,GAD65 and GAD67) was investigated in rat jejunum.Meanwhile, double staining was performed with GAD65 immunohistochemistry, followed by lectin histochemistry of fluorescent wheat germ agglutinin. Furthermore,evaluation of cell kinetics in jejunum was conducted by 3Hthymidine autoradiography and immunohistochemistry using a monoclonal antibody to proliferating cell nuclear antigen (PCNA).RESULTS: The cells showing positive immunoreactivity GABA and GAD65 were mainly distributed in the villi in rat jejunum, while jejunal epithelial cells were negative for GAD67. Positive GABA or GAD65 staining was mainly located in the cytoplasm and along the brush border of epithelial cells in the middle and upper portions. In addition, a few GABA and GAD65 strongly positive cells were scattered in the upper two thirds of jejunal villi. Double staining showed that GAD65 immunoreactivity was not found in goblet cells.3H-thymidine-labeled nuclei were found in the lower and middle portions of jejunal crypts, which was consistent with PCNA staining. Therefore, GABA and GAD65 were expressed in a maturation or functional zone.CONCLUSION: The characteristic expression of GABA and GAD suggests that GABA might be involved in regulation of differentiation and maturation of epithelial cells in rat jejunum.

  12. 4-Vinylphenol biosynthesis from cellulose as the sole carbon source using phenolic acid decarboxylase- and tyrosine ammonia lyase-expressing Streptomyces lividans.

    Science.gov (United States)

    Noda, Shuhei; Kawai, Yoshifumi; Tanaka, Tsutomu; Kondo, Akihiko

    2015-03-01

    Streptomyces lividans was adopted as a host strain for 4-vinylphenol (4VPh) production directly from cellulose. In order to obtain novel phenolic acid decarboxylase (PAD) expressed in S. lividans, PADs distributed among Streptomyces species were screened. Three novel PADs, derived from Streptomycessviceus, Streptomyceshygroscopicus, and Streptomycescattleya, were successfully obtained and expressed in S. lividans. S. sviceus PAD (SsPAD) could convert p-hydroxycinnamic acid (pHCA) to 4VPh more efficiently than the others both in vitro and in vivo. For 4VPh production directly from cellulose, l-tyrosine ammonia lyase derived from Rhodobacter sphaeroides and SsPAD were introduced into endoglucanase-secreting S. lividans, and the 4VPh biosynthetic pathway was constructed therein. The created transformants successfully produced 4VPh directly from cellulose.

  13. Expression of messenger RNAs for glutamic acid decarboxylase, preprotachykinin, cholecystokinin, somatostatin, proenkephalin and neuropeptide Y in the adult rat superior colliculus.

    Science.gov (United States)

    Harvey, A R; Heavens, R P; Yellachich, L A; Sirinathsinghji, D J

    2001-01-01

    The mammalian superior colliculus is an important subcortical integrator of sensorimotor behaviours. It is multi-layered, each layer containing specific neuronal types and possessing distinct input/output relationships. Here we use in situ hybridisation methods to map the distribution of seven neurotransmitters/neuromodulator systems in adult rat superior colliculus. Coronal sections were probed for preprotachykinin, cholecystokinin, somatostatin, proenkephalin, neuropeptide Y and the enzymes glutamic acid decarboxylase and choline acetyltransferase, markers for GABA and acetylcholine respectively. Cells expressing glutamic acid decarboxylase messenger RNA were the most abundant, the highest density being found in the superficial layers. Many cells containing proprotachykinin messenger RNA were found in stratum zonale and the upper two-thirds of stratum griseum superficiale; cells were also located in deeper tectal laminae, particularly caudomedially. Most cholecystokinin messenger RNA expressing cells were located in the superficial layers with a prominent band in the middle third of stratum griseum superficiale. Cells expressing moderate to high levels of somatostatin messenger RNA formed a dense band in the lower third of stratum griseum superficiale/upper stratum opticum; two less distinct tiers of labelling were seen in deeper layers. These in situ hybridisation data reveal three distinct sub-laminae in rat stratum griseum superficiale. Cells expressing moderate to low levels of proenkephalin messenger RNA were located in lower stratum griseum superficiale/upper stratum opticum and intermediate laminae. A cluster of enkephalinergic cells was located medially in the deep tectal laminae. Expression of neuropeptide Y messenger RNA was relatively low and mostly confined to cells in stratum griseum superficiale and stratum opticum. No choline acetyltransferase messenger RNA was detected. This in situ analysis of seven different neurotransmitters

  14. Styrene production from a biomass-derived carbon source using a coculture system of phenylalanine ammonia lyase and phenylacrylic acid decarboxylase-expressing Streptomyces lividans transformants.

    Science.gov (United States)

    Fujiwara, Ryosuke; Noda, Shuhei; Tanaka, Tsutomu; Kondo, Akihiko

    2016-12-01

    To produce styrene from a biomass-derived carbon source, Streptomyces lividans was adopted as a host strain. The gene encoding ferulic acid decarboxylase from Saccharomyces cerevisiae (FDC1) was introduced into S. lividans, and the resulting S. lividans transformant successfully expressed FDC1 and converted trans-cinnamic acid (CA) to styrene. A key factor in styrene production using microbes is the recovery of volatile styrene. In the present study, we selected polystyrene resin beads XRD-4 as the absorbent agent to recover styrene produced using S. lividans transformants, which enabled recovery of styrene from the culture broth. For styrene production from biomass-derived carbon sources, S. lividans/FDC1 was cultured together with S. lividans/p-encP, which we previously reported as a CA-producing S. lividans strain. This coculture system combined with the recovery of styrene using XAD-4 allowed the production of styrene from glucose, cellobiose, or xylo-oligosaccharide, respectively.

  15. Cerebellar Ataxia and Glutamic Acid Decarboxylase Antibodies

    Science.gov (United States)

    Ariño, Helena; Gresa-Arribas, Nuria; Blanco, Yolanda; Martínez-Hernández, Eugenia; Sabater, Lidia; Petit-Pedrol, Mar; Rouco, Idoia; Bataller, Luis; Dalmau, Josep O.; Saiz, Albert; Graus, Francesc

    2016-01-01

    IMPORTANCE Current clinical and immunologic knowledge on cerebellar ataxia (CA) with glutamic acid decarboxylase 65 antibodies (GAD65-Abs) is based on case reports and small series with short-term follow-up data. OBJECTIVE To report the symptoms, additional antibodies, prognostic factors, and long-term outcomes in a cohort of patients with CA and GAD65-Abs. DESIGN, SETTING, AND PARTICIPANTS Retrospective cohort study and laboratory investigations at a center for autoimmune neurologic disorders among 34 patients with CA and GAD65-Abs, including 25 with long-term follow-up data (median, 5.4 years; interquartile range, 3.1-10.3 years). MAIN OUTCOMES AND MEASURES Analysis of clinicoimmunologic features and predictors of response to immunotherapy. Immunochemistry on rat brain, cultured neurons, and human embryonic kidney cells expressing GAD65, GAD67, α1-subunit of the glycine receptor, and a repertoire of known cell surface autoantigens were used to identify additional antibodies. Twenty-eight patients with stiff person syndrome and GAD65-Abs served as controls. RESULTS The median age of patients was 58 years (range, 33-80 years); 28 of 34 patients (82%) were women. Nine patients (26%) reported episodes of brainstem and cerebellar dysfunction or persistent vertigo several months before developing CA. The clinical presentation was subacute during a period of weeks in 13 patients (38%). Nine patients (26%) had coexisting stiff person syndrome symptoms. Systemic organ-specific autoimmunities (type 1 diabetes mellitus and others) were present in 29 patients (85%). Twenty of 25 patients with long-term follow-up data received immunotherapy (intravenous immunoglobulin in 10 and corticosteroids and intravenous immunoglobulin or other immunosuppressors in 10), and 7 of them (35%) improved. Predictors of clinical response included subacute onset of CA (odds ratio [OR], 0.50; 95% CI, 0.25-0.99; P = .047) and prompt immunotherapy (OR, 0.98; 95% CI, 0.96-0.99; P = .01). Similar

  16. Consequence of nigrostriatal denervation and L-dopa therapy on the expression of glutamic acid decarboxylase messenger RNA in the pallidum.

    Science.gov (United States)

    Herrero, M T; Levy, R; Ruberg, M; Luquin, M R; Villares, J; Guillen, J; Faucheux, B; Javoy-Agid, F; Guridi, J; Agid, Y; Obeso, J A; Hirsch, E C

    1996-07-01

    To examine the consequences of nigrostriatal denervation and L-dopa treatment on the basal ganglia output system, we analyzed, by quantitative in situ hybridization, the messenger RNA coding for glutamic acid decarboxylase (Mr 67,000) (GAD67 mRNA) in pallidal cells from patients with Parkinson's disease (PD), monkeys rendered parkinsonian by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) receiving or not receiving L-dopa, and their respective control subjects. In MPTP-treated monkeys, the expression of GAD67 mRNA was increased in cells from the internal pallidum, and this effect was abolished by L-dopa treatment. There were no differences in the levels of GAD67 mRNA between patients with PD, who were all treated with L-dopa, and control subjects. These results indicate that the level of GAD67 mRNA is increased in the cells of the internal pallidum after nigrostriatal dopaminergic denervation and that this increase can be reversed by L-dopa therapy.

  17. Induction of aromatic-L-amino acid decarboxylase by decarboxylase inhibitors in idiopathic parkinsonism.

    Science.gov (United States)

    Boomsma, F; Meerwaldt, J D; Man in 't Veld, A J; Hovestadt, A; Schalekamp, M A

    1989-06-01

    We evaluated the effect of administration of L-dopa, alone or in combination with a peripheral decarboxylase inhibitor, on plasma levels of aromatic-L-amino acid decarboxylase (ALAAD). After single-dose administration of L-dopa plus benserazide (Madopar) in healthy subjects and in chronically treated patients with parkinsonism, plasma ALAAD followed for 2 to 3 hours fell, but returned to predosing levels within 90 minutes. Four groups of patients with idiopathic parkinsonism were studied during chronic treatment: Group I, no L-dopa treatment (n = 31); Group II, L-dopa alone (n = 15); Group III, L-dopa plus benserazide (n = 28); and Group IV, L-dopa plus carbidopa (Sinemet, n = 30). Plasma ALAAD 2 hours after dosing was normal in Groups I and II. ALAAD was increased threefold in Groups III and IV, suggesting induction of ALAAD by the coadministration of a peripheral decarboxylase inhibitor. In a study of 3 patients in whom L-dopa/benserazide was started, plasma ALAAD rose gradually over 3 to 4 weeks. Further detailed pharmacokinetic studies of L-dopa, dopamine, and ALAAD in plasma and cerebrospinal fluid are required to determine if the apparent ALAAD induction by a peripheral decarboxylase inhibitor may be related to the loss of clinical efficacy of combination therapy in some patients and how it is related to end-of-dose deterioration and on-off phenomena.

  18. Lotus hairy roots expressing inducible arginine decarboxylase activity.

    Science.gov (United States)

    Chiesa, María A; Ruiz, Oscar A; Sánchez, Diego H

    2004-05-01

    Biotechnological uses of plant cell-tissue culture usually rely on constitutive transgene expression. However, such expression of transgenes may not always be desirable. In those cases, the use of an inducible promoter could be an alternative approach. To test this hypothesis, we developed two binary vectors harboring a stress-inducible promoter from Arabidopsis thaliana, driving the beta-glucuronidase reporter gene and the oat arginine decarboxylase. Transgenic hairy roots of Lotus corniculatus were obtained with osmotic- and cold-inducible beta-glucuronidase and arginine decarboxylase activities. The increase in the activity of the latter was accompanied by a significant rise in total free polyamines level. Through an organogenesis process, we obtained L. corniculatus transgenic plants avoiding deleterious phenotypes frequently associated with the constitutive over-expression of arginine decarboxylation and putrescine accumulation.

  19. Expression of arginine decarboxylase and ornithine decarboxylase genes in apple cells and stressed shoots.

    Science.gov (United States)

    Hao, Yu-Jin; Kitashiba, Hiroyasu; Honda, Chikako; Nada, Kazuyoshi; Moriguchi, Takaya

    2005-04-01

    Arginine decarboxylase (ADC) and ornithine decarboxylase (ODC) are two important enzymes responsible for putrescine biosynthesis. In this study, a full-length ADC cDNA (MdADC) was isolated from apple [Malus sylvestris (L.) Mill. var. domestica (Borkh.) Mansf.]. Meanwhile, a partial ODC (pMdODC) could be amplified only by a second RCR from the RT-PCR products, whereas a full-length ODC could not be obtained by either cDNA library screening or 5'- and 3'-RACEs, suggesting quite low expression. Moreover, D-arginine, an ADC inhibitor, caused a decrease in ADC activity and severely inhibited the growth of apple callus, which could be partially resumed by exogenous addition of putrescine, whereas alpha-difluoromethylornithine (DFMO), an inhibitor for ODC, caused the incomplete repression of callus growth without changing ODC activity. RNA gel blot showed that the expression level of MdADC was high in young tissues/organs with rapid cell division and was positively induced by chilling, salt, and dehydration, implying its involvement in both cell growth and these stress responses. By contrast, the transcript of ODC could not be detected by RNA gel blot analysis. Based on the present study, it is possible to conclude that (i) the ODC pathway is active in apple, although the expression level of the pMdODC gene homologous with its counterparts found in other plant species is quite low; and (ii) MdADC expression correlates with cell growth and stress responses to chilling, salt, and dehydration, suggesting that ADC is a primary biosynthetic pathway for putrescine biosynthesis in apple.

  20. [Inhibitory effect of essential oils, food additives, peracetic acid and detergents on bacterial histidine decarboxylase].

    Science.gov (United States)

    Kamii, Eri; Terada, Gaku; Akiyama, Jyunki; Isshiki, Kenji

    2011-01-01

    The aim of this study is to examine whether various essential oils, food additives, peracetic acid and detergents inhibit bacterial histidine decarboxylase. Crude extract of Morganella morganii NBRC3848 was prepared and incubated with various agents. Histidine decarboxylase activity was significantly inhibited (pperacetic acid caused slight decomposition. Histidine and histamine were stable in the presence of the other 24 agents. These results indicated that 25 of the agents examined were inhibitors of histidine decarboxylase.

  1. Glutamic acid decarboxylase isoform distribution in transgenic mouse septum: an anti-GFP immunofluorescence study.

    Science.gov (United States)

    Verimli, Ural; Sehirli, Umit S

    2016-09-01

    The septum is a basal forebrain region located between the lateral ventricles in rodents. It consists of lateral and medial divisions. Medial septal projections regulate hippocampal theta rhythm whereas lateral septal projections are involved in processes such as affective functions, memory formation, and behavioral responses. Gamma-aminobutyric acidergic neurons of the septal region possess the 65 and 67 isoforms of the enzyme glutamic acid decarboxylase. Although data on the glutamic acid decarboxylase isoform distribution in the septal region generally appears to indicate glutamic acid decarboxylase 67 dominance, different studies have given inconsistent results in this regard. The aim of this study was therefore to obtain information on the distributions of both of these glutamic acid decarboxylase isoforms in the septal region in transgenic mice. Two animal groups of glutamic acid decarboxylase-green fluorescent protein knock-in transgenic mice were utilized in the experiment. Brain sections from the region were taken for anti-green fluorescent protein immunohistochemistry in order to obtain estimated quantitative data on the number of gamma-aminobutyric acidergic neurons. Following the immunohistochemical procedures, the mean numbers of labeled cells in the lateral and medial septal nuclei were obtained for the two isoform groups. Statistical analysis yielded significant results which indicated that the 65 isoform of glutamic acid decarboxylase predominates in both lateral and medial septal nuclei (unpaired two-tailed t-test p glutamic acid decarboxylase isoform 65 in the septal region in glutamic acid decarboxylase-green fluorescent protein transgenic mice.

  2. Glutamatergic or GABAergic neuron-specific, long-term expression in neocortical neurons from helper virus-free HSV-1 vectors containing the phosphate-activated glutaminase, vesicular glutamate transporter-1, or glutamic acid decarboxylase promoter.

    Science.gov (United States)

    Rasmussen, Morten; Kong, Lingxin; Zhang, Guo-rong; Liu, Meng; Wang, Xiaodan; Szabo, Gabor; Curthoys, Norman P; Geller, Alfred I

    2007-05-01

    Many potential uses of direct gene transfer into neurons require restricting expression to one of the two major types of forebrain neurons, glutamatergic or GABAergic neurons. Thus, it is desirable to develop virus vectors that contain either a glutamatergic or GABAergic neuron-specific promoter. The brain/kidney phosphate-activated glutaminase (PAG), the product of the GLS1 gene, produces the majority of the glutamate for release as neurotransmitter, and is a marker for glutamatergic neurons. A PAG promoter was partially characterized using a cultured kidney cell line. The three vesicular glutamate transporters (VGLUTs) are expressed in distinct populations of neurons, and VGLUT1 is the predominant VGLUT in the neocortex, hippocampus, and cerebellar cortex. Glutamic acid decarboxylase (GAD) produces GABA; the two molecular forms of the enzyme, GAD65 and GAD67, are expressed in distinct, but largely overlapping, groups of neurons, and GAD67 is the predominant form in the neocortex. In transgenic mice, an approximately 9 kb fragment of the GAD67 promoter supports expression in most classes of GABAergic neurons. Here, we constructed plasmid (amplicon) Herpes Simplex Virus (HSV-1) vectors that placed the Lac Z gene under the regulation of putative PAG, VGLUT1, or GAD67 promoters. Helper virus-free vector stocks were delivered into postrhinal cortex, and the rats were sacrificed 4 days or 2 months later. The PAG or VGLUT1 promoters supported approximately 90% glutamatergic neuron-specific expression. The GAD67 promoter supported approximately 90% GABAergic neuron-specific expression. Long-term expression was observed using each promoter. Principles for obtaining long-term expression from HSV-1 vectors, based on these and other results, are discussed. Long-term glutamatergic or GABAergic neuron-specific expression may benefit specific experiments on learning or specific gene therapy approaches. Of note, promoter analyses might identify regulatory elements that determine

  3. Glutamic acid decarboxylase autoimmunity in Batten disease and other disorders.

    Science.gov (United States)

    Pearce, David A; Atkinson, Mark; Tagle, Danilo A

    2004-12-14

    Degenerative diseases of the CNS, such as stiff-person syndrome (SPS), progressive cerebellar ataxia, and Rasmussen encephalitis, have been characterized by the presence of autoantibodies. Recent findings in individuals with Batten disease and in animal models for the disorder indicate that this condition may be associated with autoantibodies against glutamic acid decarboxylase (GAD), an enzyme that converts the excitatory neurotransmitter glutamate to the inhibitory neurotransmitter gamma-aminobutyric acid (GABA). Anti-GAD autoantibodies could result in excess excitatory neurotransmitters, leading to the seizures and other symptoms observed in patients with Batten disease. The pathogenic potential of GAD autoantibodies is examined in light of what is known for other autoimmune disorders, such as multiple sclerosis, SPS, Rasmussen encephalitis, and type 1 diabetes, and may have radical implications for diagnosis and management of Batten disease.

  4. Overexpression, purification, crystallization and preliminary structural studies of p-coumaric acid decarboxylase from Lactobacillus plantarum

    Energy Technology Data Exchange (ETDEWEB)

    Rodríguez, Héctor; Rivas, Blanca de las; Muñoz, Rosario [Instituto de Fermentaciones Industriales, CSIC, Juan de la Cierva 3, 28006 Madrid (Spain); Mancheño, José M., E-mail: xjosemi@iqfr.csic.es [Grupo de Cristalografía Macromolecular y Biología Estructural, Instituto Rocasolano, CSIC, Serrano 119, 28006 Madrid (Spain); Instituto de Fermentaciones Industriales, CSIC, Juan de la Cierva 3, 28006 Madrid (Spain)

    2007-04-01

    The enzyme p-coumaric acid decarboxylase (PDC) from L. plantarum has been recombinantly expressed, purified and crystallized. The structure has been solved at 2.04 Å resolution by the molecular-replacement method. The substrate-inducible p-coumaric acid decarboxylase (PDC) from Lactobacillus plantarum has been overexpressed in Escherichia coli, purified and confirmed to possess decarboxylase activity. The recombinant His{sub 6}-tagged enzyme was crystallized using the hanging-drop vapour-diffusion method from a solution containing 20%(w/v) PEG 4000, 12%(w/v) 2-propanol, 0.2 M sodium acetate, 0.1 M Tris–HCl pH 8.0 with 0.1 M barium chloride as an additive. Diffraction data were collected in-house to 2.04 Å resolution. Crystals belonged to the tetragonal space group P4{sub 3}, with unit-cell parameters a = b = 43.15, c = 231.86 Å. The estimated Matthews coefficient was 2.36 Å{sup 3} Da{sup −1}, corresponding to 48% solvent content, which is consistent with the presence of two protein molecules in the asymmetric unit. The structure of PDC has been determined by the molecular-replacement method. Currently, the structure of PDC complexed with substrate analogues is in progress, with the aim of elucidating the structural basis of the catalytic mechanism.

  5. The Degradation of 14C-Glutamic Acid by L-Glutamic Acid Decarboxylase.

    Science.gov (United States)

    Dougherty, Charles M; Dayan, Jean

    1982-01-01

    Describes procedures and semi-micro reaction apparatus (carbon dioxide trap) to demonstrate how a particular enzyme (L-Glutamic acid decarboxylase) may be used to determine the site or sites of labeling in its substrate (carbon-14 labeled glutamic acid). Includes calculations, solutions, and reagents used. (Author/SK)

  6. Expression of ornithine decarboxylase in precancerous and cancerous gastric lesions

    Institute of Scientific and Technical Information of China (English)

    Xin-Pu Miao; Jian-Sheng Li; Hui-Yan Li; Shi-Ping Zeng; Ye Zhao; Jiang-Zheng Zeng

    2007-01-01

    AIM:To investigate the expression of ornithine decarboxylase (ODC) in precancerous and cancerous gastric lesions.METHODS: We studied the expression of ODC in gastric mucosa from patients with chronic superficial gastritis (CSG, n = 32), chronic atrophic gastritis [CAG, n = 43;15 with and 28 without intestinal metaplasia (IM)],gastric dysplasia (DYS, n = 11) and gastric cancer (GC,n = 48) tissues using immunohistochemical staining. All 134 biopsy specimens of gastric mucosa were collected by gastroscopy.METHODS: The positive rate of ODC expression was 34.4%, 42.9%, 73.3%, 81.8% and 91.7% in cases with CSG, CAG without IM, CAG with IM, DYS and GC, respectively (P < 0.01), The positive rate of ODC expression increased in the order of CSG < CAG (without IM) < CAG (with IM) < DYS and finally, GC. In addition,ODC positive immunostaining rate was lower in welldifferentiated GC than in poorly-differentiated GC (P <0.05).CONCLUSION: The expression of ODC is positively correlated with the degree of malignity of gastric mucosa and development of gastric lesions. This finding indicates that ODC may be used as a good biomarker in the screening and diagnosis of precancerous lesions.

  7. Pancreatic beta cells express two autoantigenic forms of glutamic acid decarboxylase, a 65-kDa hydrophilic form and a 64-kDa amphiphilic form which can be both membrane-bound and soluble

    DEFF Research Database (Denmark)

    Christgau, S; Schierbeck, H; Aanstoot, H J;

    1991-01-01

    The 64-kDa pancreatic beta-cell autoantigen, which is a target of autoantibodies associated with early as well as progressive stages of beta-cell destruction, resulting in insulin-dependent diabetes (IDDM) in humans, has been identified as the gamma-aminobutyric acid-synthesizing enzyme glutamic...... acid decarboxylase. We have identified two autoantigenic forms of this protein in rat pancreatic beta-cells, a Mr 65,000 (GAD65) hydrophilic and soluble form of pI 6.9-7.1 and a Mr 64,000 (GAD64) component of pI 6.7. GAD64 is more abundant than GAD65 and has three distinct forms with regard to cellular...

  8. AUTOANTIBODIES TO GLUTAMIC ACID DECARBOXYLASE AS A PATHOGENETIC MARKER OF TYPE I DIABETES MELLITUS

    Directory of Open Access Journals (Sweden)

    N. V. Piven

    2011-01-01

    Full Text Available Abstract. A new method of enzyme-linked immunosorbent assay (in solid-phase ELISA format has been developed to determine concentrations of autoantibodies to glutamic acid decarboxylase, as well as an evidencebased methodology is proposed for its medical implications, as a quantitative pathogenetic predictive marker of autoimmune diagnostics in type 1 diabetes mellitus. This technique could be implied for serial production of diagnostic reagent kits, aimed for detection of autoantibodies to glutamic acid decarboxylase by means of ELISA approach. (Med. Immunol., 2011, vol. 13, N 2-3, pp 257-260

  9. Glutamate alteration of glutamic acid decarboxylase (GAD) in GABAergic neurons: the role of cysteine proteases.

    Science.gov (United States)

    Monnerie, Hubert; Le Roux, Peter D

    2008-09-01

    Brain cell vulnerability to neurologic insults varies greatly, depending on their neuronal subpopulation. Among cells that survive a pathological insult such as ischemia or brain trauma, some may undergo morphological and/or biochemical changes that could compromise brain function. We previously reported that surviving cortical GABAergic neurons exposed to glutamate in vitro displayed an NMDA receptor (NMDAR)-mediated alteration in the levels of the GABA synthesizing enzyme glutamic acid decarboxylase (GAD65/67) [Monnerie, H., Le Roux, P., 2007. Reduced dendrite growth and altered glutamic acid decarboxylase (GAD) 65- and 67-kDa isoform protein expression from mouse cortical GABAergic neurons following excitotoxic injury in vitro. Exp. Neurol. 205, 367-382]. In this study, we examined the mechanisms by which glutamate excitotoxicity caused a change in cortical GABAergic neurons' GAD protein levels. Removing extracellular calcium prevented the NMDAR-mediated decrease in GAD protein levels, measured using Western blot techniques, whereas inhibiting calcium entry through voltage-gated calcium channels had no effect. Glutamate's effect on GAD protein isoforms was significantly attenuated by preincubation with the cysteine protease inhibitor N-Acetyl-L-Leucyl-L-Leucyl-L-norleucinal (ALLN). Using class-specific protease inhibitors, we observed that ALLN's effect resulted from the blockade of calpain and cathepsin protease activities. Cell-free proteolysis assay confirmed that both proteases were involved in glutamate-induced alteration in GAD protein levels. Together these results suggest that glutamate-induced excitotoxic stimulation of NMDAR in cultured cortical neurons leads to altered GAD protein levels from GABAergic neurons through intracellular calcium increase and protease activation including calpain and cathepsin. Biochemical alterations in surviving cortical GABAergic neurons in various disease states may contribute to the altered balance between excitation

  10. Sensing and adaptation to low pH mediated by inducible amino acid decarboxylases in Salmonella.

    Directory of Open Access Journals (Sweden)

    Julie P M Viala

    Full Text Available During the course of infection, Salmonella enterica serovar Typhimurium must successively survive the harsh acid stress of the stomach and multiply into a mild acidic compartment within macrophages. Inducible amino acid decarboxylases are known to promote adaptation to acidic environments. Three low pH inducible amino acid decarboxylases were annotated in the genome of S. Typhimurium, AdiA, CadA and SpeF, which are specific for arginine, lysine and ornithine, respectively. In this study, we characterized and compared the contributions of those enzymes in response to acidic challenges. Individual mutants as well as a strain deleted for the three genes were tested for their ability (i to survive an extreme acid shock, (ii to grow at mild acidic pH and (iii to infect the mouse animal model. We showed that the lysine decarboxylase CadA had the broadest range of activity since it both had the capacity to promote survival at pH 2.3 and growth at pH 4.5. The arginine decarboxylase AdiA was the most performant in protecting S. Typhimurium from a shock at pH 2.3 and the ornithine decarboxylase SpeF conferred the best growth advantage under anaerobiosis conditions at pH 4.5. We developed a GFP-based gene reporter to monitor the pH of the environment as perceived by S. Typhimurium. Results showed that activities of the lysine and ornithine decarboxylases at mild acidic pH did modify the local surrounding of S. Typhimurium both in culture medium and in macrophages. Finally, we tested the contribution of decarboxylases to virulence and found that these enzymes were dispensable for S. Typhimurium virulence during systemic infection. In the light of this result, we examined the genomes of Salmonella spp. normally responsible of systemic infection and observed that the genes encoding these enzymes were not well conserved, supporting the idea that these enzymes may be not required during systemic infection.

  11. Evolution and expression analysis of the soybean glutamate decarboxylase gene family

    Indian Academy of Sciences (India)

    Tae Kyung Hyun; Seung Hee Eom; Xiao Han; Ju-Sung Kim

    2014-12-01

    Glutamate decarboxylase (GAD) is an enzyme that catalyses the conversion of L-glutamate into -aminobutyric acid (GABA), which is a four-carbon non-protein amino acid present in all organisms. Although plant GAD plays important roles in GABA biosynthesis, our knowledge concerning GAD gene family members and their evolutionary relationship remains limited. Therefore, in this study, we have analysed the evolutionary mechanisms of soybean GAD genes and suggested that these genes expanded in the soybean genome partly due to segmental duplication events. The approximate dates of duplication events were calculated using the synonymous substitution rate, and we suggested that the segmental duplication of GAD genes in soybean originated 9.47 to 11.84 million years ago (Mya). In addition, all segmental duplication pairs (GmGAD1/3 and GmGAD2/4) are subject to purifying selection. Furthermore, GmGAD genes displayed differential expression either in their transcript abundance or in their expression patterns under abiotic stress conditions like salt, drought, and cold. The expression pattern of paralogous pairs suggested that they might have undergone neofunctionalization during the subsequent evolution process. Taken together, our results provide valuable information for the evolution of the GAD gene family and represent the basis for future research on the functional characterization of GAD genes in higher plants.

  12. Production of dopamine by aromatic L-amino acid decarboxylase cells after spinal cord injury

    DEFF Research Database (Denmark)

    Ren, Liqun; Wienecke, Jacob; Hultborn, Hans;

    2016-01-01

    Aromatic L-amino acid decarboxylase (AADC) cells are widely distributed in the spinal cord and their functions are largely unknown. We have previously found that AADC cells in the spinal cord could increase their ability to produce serotonin from 5-hydroxytryptophan after spinal cord injury (SCI)...

  13. Clinical and biochemical features of aromatic L-amino acid decarboxylase deficiency.

    NARCIS (Netherlands)

    Brun, L.; Ngu, L.H.; Keng, W.T.; Ch'ng, G.S.; Choy, Y.S.; Hwu, W.L.; Lee, W.T.; Willemsen, M.A.A.P.; Verbeek, M.M.; Wassenberg, T.; Regal, L.; Orcesi, S.; Tonduti, D.; Accorsi, P.; Testard, H.; Abdenur, J.E.; Tay, S.; Allen, G.F.; Heales, S.; Kern, I.; Kato, M.; Burlina, A.; Manegold, C.; Hoffmann, G.F.; Blau, N.

    2010-01-01

    OBJECTIVE: To describe the current treatment; clinical, biochemical, and molecular findings; and clinical follow-up of patients with aromatic l-amino acid decarboxylase (AADC) deficiency. METHOD: Clinical and biochemical data of 78 patients with AADC deficiency were tabulated in a database of pediat

  14. Chilling Tolerance of Cucumber During Germination is Related to Expression of Lysine Decarboxylase Gene

    Institute of Scientific and Technical Information of China (English)

    LU Ming-hui; LI Xiao-ming; CHEN Jin-feng; CHEN Long-zheng; QIAN Chun-tao

    2005-01-01

    Using cDNA-AFLP technique, a specific fragment was isolated from cucumber cultivar Changchun mici possessing chilling tolerance induced at low temperature (15℃). This fragment, named cctr 132, could not be induced in the chilling sensitive cucumber cultivar Beijing jietou. After recovering the fragment, sequencing and translating, the results of blastx and blastp in GenBank of NCBI indicated that CCTR132 had 88.37% identities and 100% positives with Oryza sativa putative lysine decarboxylase-like protein respectively, and PGGXGTXXE, the putative conserved domain of lysine decarboxylase family, was detected from CCTR132, suggesting the cucumber chilling tolerance during germination is related to the expression of the lysine decarboxylase gene.

  15. Cloning of tomato (Lycopersicon esculentum Mill.) arginine decarboxylase gene and its expression during fruit ripening.

    Science.gov (United States)

    Rastogi, R; Dulson, J; Rothstein, S J

    1993-11-01

    Arginine decarboxylase (ADC) is the first enzyme in one of the two pathways of putrescine biosynthesis in plants. The genes encoding ADC have previously been cloned from oat and Escherichia coli. Degenerate oligonucleotides corresponding to two conserved regions of ADC were used as primers in polymerase chain reaction amplification of tomato (Lycopersicon esculentum Mill.) genomic DNA, and a 1.05-kb fragment was obtained. This genomic DNA fragment encodes an open reading frame of 350 amino acids showing about 50% identity with the oat ADC protein. Using this fragment as a probe, we isolated several partial ADC cDNA clones from a tomato pericarp cDNA library. The 5' end of the coding region was subsequently obtained from a genomic clone containing the entire ADC gene. The tomato ADC gene contains an open reading frame encoding a polypeptide of 502 amino acids and a predicted molecular mass of about 55 kD. The predicted amino acid sequence exhibits 47 and 38% identify with oat and E. coli ADCs, respectively. Gel blot hybridization experiments show that, in tomato, ADC is encoded by a single gene and is expressed as a transcript of approximately 2.2 kb in the fruit pericarp and leaf tissues. During fruit ripening the amount of ADC transcript appeared to peak at the breaker stage. No significant differences were seen when steady-state ADC mRNA levels were compared between normal versus long-keeping Alcobaca (alc) fruit, although alc fruit contain elevated putrescine levels and ADC activity at the ripe stage. The lack of correlation between ADC activity and steady-state mRNA levels in alc fruit suggests a translational and/or posttranslational regulation of ADC gene expression during tomato fruit ripening.

  16. The role of aromatic L-amino acid decarboxylase in bacillamide C biosynthesis by Bacillus atrophaeus C89

    OpenAIRE

    Lei Yuwen; Feng-Li Zhang; Qi-Hua Chen; Shuang-Jun Lin; Yi-Lei Zhao; Zhi-Yong Li

    2013-01-01

    For biosynthesis of bacillamide C by Bacillus atrophaeus C89 associated with South China sea sponge Dysidea avara, it is hypothesized that decarboxylation from L-tryptophan to tryptamine could be performed before amidation by the downstream aromatic L-amino acid decarboxylase (AADC) to the non-ribosomal peptide synthetases (NRPS) gene cluster for biosynthesizing bacillamide C. The structural analysis of decarboxylases' known substrates in KEGG database and alignment analysis of amino acid seq...

  17. Tissue and regional distribution of cysteic acid decarboxylase. A new assay method.

    Science.gov (United States)

    Wu, J Y; Moss, L G; Chen, M S

    1979-04-01

    A sensitive and rapid assay method method for cysteic acid decarboxylase was develped which combined the selectivity of ion exchange resin (a complete retention of the substrate, cysteic acid, and exclusion of the product, taurine) with the speed of a vacuum filtration. The synthesis and purification of 35S-labeled cysteic acid were described. The validity of the assay was established by the identification of the reaction product as taurine. With this new method, the decarboxylase activity was measured in discrete regions of bovine brain. Putamen had the highest activity, 172 pmol taurine formed/min/mg protein (100%), followed by caudate nucleus, 90%; cerebral cortex, 82%; hypothalamus, 81%; cerebellar cortex, 79%; cerebellar peduncle, 59%; thalamus, 42%; brain stem, 25%; pons, 10%; and corpus callosum, 3%. The decarboxylase activity in various mouse tissues was also determined as follows: liver, 403; brain, 145; kidney, 143; spinal cord, 59; lung, 21; and spleen, 10 pmol taurine formed/min/mg. No activity could be detected in skeleton muscle and heart, suggesting a different biosynthetic pathway for taurine synthesis in these tissues. The advantages and disadvantages of the new assay method are also discussed.

  18. Sequencing, characterization, and gene expression analysis of the histidine decarboxylase gene cluster of Morganella morganii.

    Science.gov (United States)

    Ferrario, Chiara; Borgo, Francesca; de Las Rivas, Blanca; Muñoz, Rosario; Ricci, Giovanni; Fortina, Maria Grazia

    2014-03-01

    The histidine decarboxylase gene cluster of Morganella morganii DSM30146(T) was sequenced, and four open reading frames, named hdcT1, hdc, hdcT2, and hisRS were identified. Two putative histidine/histamine antiporters (hdcT1 and hdcT2) were located upstream and downstream the hdc gene, codifying a pyridoxal-P dependent histidine decarboxylase, and followed by hisRS gene encoding a histidyl-tRNA synthetase. This organization was comparable with the gene cluster of other known Gram negative bacteria, particularly with that of Klebsiella oxytoca. Recombinant Escherichia coli strains harboring plasmids carrying the M. morganii hdc gene were shown to overproduce histidine decarboxylase, after IPTG induction at 37 °C for 4 h. Quantitative RT-PCR experiments revealed the hdc and hisRS genes were highly induced under acidic and histidine-rich conditions. This work represents the first description and identification of the hdc-related genes in M. morganii. Results support the hypothesis that the histidine decarboxylation reaction in this prolific histamine producing species may play a role in acid survival. The knowledge of the role and the regulation of genes involved in histidine decarboxylation should improve the design of rational strategies to avoid toxic histamine production in foods.

  19. Phosphorylation of Ser-204 and Tyr-405 in human malonyl-CoA decarboxylase expressed in silkworm Bombyx mori regulates catalytic decarboxylase activity.

    Science.gov (United States)

    Hwang, In-Wook; Makishima, Yu; Suzuki, Tomohiro; Kato, Tatsuya; Park, Sungjo; Terzic, Andre; Chung, Shin-Kyo; Park, Enoch Y

    2015-11-01

    Decarboxylation of malonyl-CoA to acetyl-CoA by malonyl-CoA decarboxylase (MCD; EC 4.1.1.9) is a vital catalytic reaction of lipid metabolism. While it is established that phosphorylation of MCD modulates the enzymatic activity, the specific phosphorylation sites associated with the catalytic function have not been documented due to lack of sufficient production of MCD with proper post-translational modifications. Here, we used the silkworm-based Bombyx mori nucleopolyhedrovirus (BmNPV) bacmid system to express human MCD (hMCD) and mapped phosphorylation effects on enzymatic function. Purified MCD from silkworm displayed post-translational phosphorylation and demonstrated coherent enzymatic activity with high yield (-200 μg/silkworm). Point mutations in putative phosphorylation sites, Ser-204 or Tyr-405 of hMCD, identified by bioinformatics and proteomics analyses reduced the catalytic activity, underscoring the functional significance of phosphorylation in modulating decarboxylase-based catalysis. Identified phosphorylated residues are distinct from the decarboxylation catalytic site, implicating a phosphorylation-induced global conformational change of MCD as responsible in altering catalytic function. We conclude that phosphorylation of Ser-204 and Tyr-405 regulates the decarboxylase function of hMCD leveraging the silkworm-based BmNPV bacmid expression system that offers a fail-safe eukaryotic production platform implementing proper post-translational modification such as phosphorylation.

  20. Cellular target recognition of perfluoroalkyl acids: In vitro evaluation of inhibitory effects on lysine decarboxylase

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Sufang; Lv, Qiyan; Yang, Yu, E-mail: yuyang@rcees.ac.cn; Guo, Liang-Hong, E-mail: LHGuo@rcees.ac.cn; Wan, Bin; Zhao, Lixia

    2014-10-15

    Perfluoroalkyl acids (PFAAs) have been shown to bind with hepatic peroxisome proliferator receptor α, estrogen receptors and human serum albumin and subsequently cause some toxic effects. Lysine decarboxylase (LDC) plays an important role in cell growth and developmental processes. In this study, the inhibitory effect of 16 PFAAs, including 13 perfluorinated carboxylic acids (PFCAs) and 3 perfluorinated sulfonic acids (PFSAs), on lysine decarboxylase (LDC) activity was investigated. The inhibition constants obtained in fluorescence enzyme assays fall in the range of 2.960 μM to 290.8 μM for targeted PFCAs, and 41.22 μM to 67.44 μM for targeted PFSAs. The inhibitory effect of PFCAs increased significantly with carbon chain (7–18 carbons), whereas the short chain PFCAs (less than 7 carbons) did not show any effect. Circular dichroism results showed that PFAA binding induced significant protein secondary structural changes. Molecular docking revealed that the inhibitory effect could be rationalized well by the cleft binding mode as well as the size, substituent group and hydrophobic characteristics of the PFAAs. At non-cytotoxic concentrations, three selected PFAAs inhibited LDC activity in HepG2 cells, and subsequently resulted in the decreased cadaverine level in the exposed cells, suggesting that LDC may be a possible target of PFAAs for their in vivo toxic effects. - Highlights: • Inhibitory effects of PFAAs on lysine decarboxylase activity were evaluated. • Four different methods were employed to investigate the mechanisms. • The long chain PFAAs showed inhibitory effect compare with 4–6 carbon chain. • The long chain PFAAs bound with LDC differently from the short ones. • The results in cells correlate with those obtained from fluorescence assay.

  1. Apraxia in anti-glutamic acid decarboxylase-associated stiff person syndrome: link to corticobasal degeneration?

    Science.gov (United States)

    Bowen, Lauren N; Subramony, S H; Heilman, Kenneth M

    2015-01-01

    Corticobasal syndrome (CBS) is associated with asymmetrical rigidity as well as asymmetrical limb-kinetic and ideomotor apraxia. Stiff person syndrome (SPS) is characterized by muscle stiffness and gait difficulties. Whereas patients with CBS have several forms of pathology, many patients with SPS have glutamic acid decarboxylase antibodies (GAD-ab), but these 2 disorders have not been reported to coexist. We report 2 patients with GAD-ab-positive SPS who also had signs suggestive of CBS, including asymmetrical limb rigidity associated with both asymmetrical limb-kinetic and ideomotor apraxia. Future studies should evaluate patients with CBS for GAD-ab and people with SPS for signs of CBS.

  2. Alterations in cerebellar glutamic acid decarboxylase (GAD) activity in a genetic model of torsion dystonia (rat).

    Science.gov (United States)

    Oltmans, G A; Beales, M; Lorden, J F; Gordon, J H

    1984-07-01

    Glutamic acid decarboxylase (GAD) activity was studied in specific brain regions of a newly identified genetic (rat) model of human torsion dystonia. GAD activity was found to be significantly increased in the deep cerebellar nuclei of dystonic rats at 16, 20, and 24 days of age. GAD activity in the other regions examined (vermis, cerebellar hemispheres, caudate nucleus, and globus pallidus) did not differ from that of age-matched normal littermate controls. Diazepam treatment significantly reduced the frequency of dystonic movements in the mutant.

  3. Glutamic acid decarboxylase antibody-positive paraneoplastic stiff limb syndrome associated with carcinoma of the breast

    Directory of Open Access Journals (Sweden)

    Agarwal Pankaj

    2010-01-01

    Full Text Available Stiff limb syndrome (SLS is a rare "focal" variant of stiff person syndrome which presents with rigidity and painful spasms of a distal limb, and abnormal fixed foot or hand postures. Anti-glutamic acid decarboxylase antibodies (GAD-Ab are variably present in most cases. Most reported cases of SLS are unassociated with cancer. We describe a patient with SLS as a paraneoplastic manifestation of breast carcinoma, in whom GAD-Ab was present. The patient responded very well to oral diazepam, baclofen and steroids.This is the third reported case of SLS as a paraneoplastic accompaniment to cancer.

  4. Glutamic acid decarboxylase antibody-positive paraneoplastic stiff limb syndrome associated with carcinoma of the breast

    OpenAIRE

    2010-01-01

    Stiff limb syndrome (SLS) is a rare "focal" variant of stiff person syndrome which presents with rigidity and painful spasms of a distal limb, and abnormal fixed foot or hand postures. Anti-glutamic acid decarboxylase antibodies (GAD-Ab) are variably present in most cases. Most reported cases of SLS are unassociated with cancer. We describe a patient with SLS as a paraneoplastic manifestation of breast carcinoma, in whom GAD-Ab was present. The patient responded very well to oral diazepam, ba...

  5. Glutamic acid decarboxylase antibody-positive paraneoplastic stiff limb syndrome associated with carcinoma of the breast.

    Science.gov (United States)

    Agarwal, Pankaj A; Ichaporia, Nasli R

    2010-01-01

    Stiff limb syndrome (SLS) is a rare "focal" variant of stiff person syndrome which presents with rigidity and painful spasms of a distal limb, and abnormal fixed foot or hand postures. Anti-glutamic acid decarboxylase antibodies (GAD-Ab) are variably present in most cases. Most reported cases of SLS are unassociated with cancer. We describe a patient with SLS as a paraneoplastic manifestation of breast carcinoma, in whom GAD-Ab was present. The patient responded very well to oral diazepam, baclofen and steroids.This is the third reported case of SLS as a paraneoplastic accompaniment to cancer.

  6. Physiological relation between respiration activity and heterologous expression of selected benzoylformate decarboxylase variants in Escherichia coli

    Directory of Open Access Journals (Sweden)

    Pohl Martina

    2010-10-01

    Full Text Available Abstract Background The benzoylformate decarboxylase (BFD from Pseudomonas putida is a biotechnologically interesting biocatalyst. It catalyses the formation of chiral 2-hydroxy ketones, which are important building blocks for stereoselective syntheses. To optimise the enzyme function often the amino acid composition is modified to improve the performance of the enzyme. So far it was assumed that a relatively small modification of the amino acid composition of a protein does not significantly influence the level of expression or media requirements. To determine, which effects these modifications might have on cultivation and product formation, six different BFD-variants with one or two altered amino acids and the wild type BFD were expressed in Escherichia coli SG13009 pKK233-2. The oxygen transfer rate (OTR as parameter for growth and metabolic activity of the different E. coli clones was monitored on-line in LB, TB and modified PanG mineral medium with the Respiratory Activity MOnitoring System (RAMOS. Results Although the E. coli clones were genetically nearly identical, the kinetics of their metabolic activity surprisingly differed in the standard media applied. Three different types of OTR curves could be distinguished. Whereas the first type (clones expressing Leu476Pro-Ser181Thr or Leu476Pro had typical OTR curves, the second type (clones expressing the wild type BFD, Ser181Thr or His281Ala showed an early drop of OTR in LB and TB medium and a drastically reduced maximum OTR in modified PanG mineral medium. The third type (clone expressing Leu476Gln behaved variable. Depending on the cultivation conditions, its OTR curve was similar to the first or the second type. It was shown, that the kinetics of the metabolic activity of the first type depended on the concentration of thiamine, which is a cofactor of BFD, in the medium. It was demonstrated that the cofactor binding strength of the different BFD-variants correlated with the differences

  7. Decarboxylase gene expression and cadaverine and putrescine production by Serratia proteamaculans in vitro and in beef.

    Science.gov (United States)

    De Filippis, Francesca; Pennacchia, Carmela; Di Pasqua, Rosangela; Fiore, Alberto; Fogliano, Vincenzo; Villani, Francesco; Ercolini, Danilo

    2013-08-01

    Studies of the molecular basis of microbial metabolic activities that are important for the changes in food quality are valuable in order to help in understanding the behavior of spoiling bacteria in food. The growth of a psychrotrophic Serratia proteamaculans strain was monitored in vitro and in artificially inoculated raw beef. Two growth temperatures (25°C and 4°C) were tested in vitro, while growth at 15°C and 4°C was monitored in beef. During growth, the expression of inducible lysine and ornithine-decarboxylase genes was evaluated by quantitative reverse transcription-PCR (qRT-PCR), while the presence of cadaverine and putrescine was quantified by LC-ESI-MS/MS. The expression of the decarboxylase genes, and the consequent production of cadaverine and putrescine were shown to be influenced by the temperature, as well as by the complexity of the growth medium. Generally, the maximum gene expression and amine production took place during the exponential and early stationary phase, respectively. In addition, lower temperatures caused slower growth and gene downregulation. Higher amounts of cadaverine compared to putrescine were found during growth in beef with the highest concentrations corresponding to microbial loads of ca. 9CFU/g. The differences found in gene expression evaluated in vitro and in beef suggested that such activities are more reliably investigated in situ in specific food matrices.

  8. Glutamate decarboxylase-dependent acid resistance in Brucella spp.: distribution and contribution to fitness under extremely acidic conditions.

    Science.gov (United States)

    Damiano, Maria Alessandra; Bastianelli, Daniela; Al Dahouk, Sascha; Köhler, Stephan; Cloeckaert, Axel; De Biase, Daniela; Occhialini, Alessandra

    2015-01-01

    Brucella is an expanding genus of major zoonotic pathogens, including at least 10 genetically very close species occupying a wide range of niches from soil to wildlife, livestock, and humans. Recently, we have shown that in the new species Brucella microti, the glutamate decarboxylase (Gad)-dependent system (GAD system) contributes to survival at a pH of 2.5 and also to infection in mice by the oral route. In order to study the functionality of the GAD system in the genus Brucella, 47 isolates, representative of all known species and strains of this genus, and 16 strains of the closest neighbor genus, Ochrobactrum, were studied using microbiological, biochemical, and genetic approaches. In agreement with the genome sequences, the GAD system of classical species was not functional, unlike that of most strains of Brucella ceti, Brucella pinnipedialis, and newly described species (B. microti, Brucella inopinata BO1, B. inopinata-like BO2, and Brucella sp. isolated from bullfrogs). In the presence of glutamate, these species were more acid resistant in vitro than classical terrestrial brucellae. Expression in trans of the gad locus from representative Brucella species in the Escherichia coli MG1655 mutant strain lacking the GAD system restored the acid-resistant phenotype. The highly conserved GAD system of the newly described or atypical Brucella species may play an important role in their adaptation to acidic external and host environments. Furthermore, the GAD phenotype was shown to be a useful diagnostic tool to distinguish these latter Brucella strains from Ochrobactrum and from classical terrestrial pathogenic Brucella species, which are GAD negative.

  9. Ornithine decarboxylase, mitogen-activated protein kinase and matrix metalloproteinase-2 expressions in human colon tumors

    Institute of Scientific and Technical Information of China (English)

    Takahiro Nemoto; Shunichiro Kubota; Hideyuki Ishida; Nobuo Murata; Daijo Hashimoto

    2005-01-01

    AIM: To investigate the expressions of omithine decarboxylase (ODC), MMP-2, and Erk, and their relationship in human colon tumors.METHODS: ODC activity, MMP-2 expression, and mitogenactivated protein (MAP) kinase activity (Erk phosphorylation) were determined in 58 surgically removed human colon tumors and their adjacent normal tissues, using [1-14C]-ornithine as a substrate, ELISA assay, and Western blotting, respectively.RESULTS: ODC activity, MMP-2 expression, and Erk phosphorylation were significantly elevated in colon tumors, compared to those in adjacent normal tissues. A significant correlation was observed between ODC activities and MMP-2 levels.CONCLUSION: This is the first report showing a significant correlation between ODC activities and MMP-2 levels in human colon tumors. As MMP-2 is involved in cancer invasion and metastasis, and colon cancer overexpresses ODC, suppression of ODC expression may be a rational approach to treat colon cancer which overexpresses ODC.

  10. Effects of glutamate decarboxylase and gamma-aminobutyric acid (GABA) transporter on the bioconversion of GABA in engineered Escherichia coli.

    Science.gov (United States)

    Le Vo, Tam Dinh; Kim, Tae Wan; Hong, Soon Ho

    2012-05-01

    Gamma-aminobutyric acid (GABA) is a non-essential amino acid and a precursor of pyrrolidone, a monomer of nylon 4. GABA can be biosynthesized through the decarboxylation of L: -glutamate by glutamate decarboxylase. In this study, the effects of glutamate decarboxylase (gadA, gadB), glutamate/GABA antiporter (gadC) and GABA aminotransferase (gabT) on GABA production were investigated in Escherichia coli. Glutamate decarboxylase was overexpressed alone or with the glutamate/GABA antiporter to enhance GABA synthesis. GABA aminotransferase, which redirects GABA into the TCA cycle, was knock-out mutated. When gadB and gadC were co-overexpressed in the gabT mutant strain, a final GABA concentration of 5.46 g/l was obtained from 10 g/l of monosodium glutamate (MSG), which corresponded to a GABA yield of 89.5%.

  11. Heterologous expression of a plant arginine decarboxylase gene in Trypanosoma cruzi.

    Science.gov (United States)

    Carrillo, Carolina; Serra, María P; Pereira, Claudio A; Huber, Alejandra; González, Nélida S; Algranati, Israel D

    2004-11-01

    Wild-type Trypanosoma cruzi epimastigotes lack arginine decarboxylase (ADC) enzymatic activity. However, the transformation of these parasites with a recombinant plasmid containing the oat ADC cDNA coding region gave rise to the transient heterologous expression of the enzyme, suggesting the absence of endogenous mechanisms that could inhibit the expression of a hypothetical own ADC gene or the assay used to measure its enzymatic activity. The foreign ADC enzyme expressed in the transgenic T. cruzi was characterized by identification of the products, the stoichiometry of the catalysed reaction, the specific inhibition by alpha-difluoromethylarginine (DFMA) and the study of its metabolic turnover. The half-life of the heterologous ADC activity in T. cruzi was about 150 min. Bioinformatics studies and polymerase chain reaction (PCR) analyses seem to indicate the absence of ADC-like DNA sequences in the wild-type T. cruzi genome.

  12. Amino acids allosterically regulate the thiamine diphosphate-dependent alpha-keto acid decarboxylase from Mycobacterium tuberculosis.

    Science.gov (United States)

    Werther, Tobias; Spinka, Michael; Tittmann, Kai; Schütz, Anja; Golbik, Ralph; Mrestani-Klaus, Carmen; Hübner, Gerhard; König, Stephan

    2008-02-29

    The gene rv0853c from Mycobacterium tuberculosis strain H37Rv codes for a thiamine diphosphate-dependent alpha-keto acid decarboxylase (MtKDC), an enzyme involved in the amino acid degradation via the Ehrlich pathway. Steady state kinetic experiments were performed to determine the substrate specificity of MtKDC. The mycobacterial enzyme was found to convert a broad spectrum of branched-chain and aromatic alpha-keto acids. Stopped-flow kinetics showed that MtKDC is allosterically activated by alpha-keto acids. Even more, we demonstrate that also amino acids are potent activators of this thiamine diphosphate-dependent enzyme. Thus, metabolic flow through the Ehrlich pathway can be directly regulated at the decarboxylation step. The influence of amino acids on MtKDC catalysis was investigated, and implications for other thiamine diphosphate-dependent enzymes are discussed.

  13. Immunotherapy-responsive limbic encephalitis with antibodies to glutamic acid decarboxylase.

    Science.gov (United States)

    Markakis, Ioannis; Alexopoulos, Harry; Poulopoulou, Cornelia; Akrivou, Sofia; Papathanasiou, Athanasios; Katsiva, Vassiliki; Lyrakos, Georgios; Gekas, Georgios; Dalakas, Marinos C

    2014-08-15

    Glutamic acid decarboxylase (GAD) has been recently identified as a target of humoral autoimmunity in a small subgroup of patients with non-paraneoplastic limbic encephalitis (NPLE). We present a patient with NPLE and positive anti-GAD antibodies who showed significant improvement after long-term immunotherapy. A 48-year old female was admitted with a two-year history of anterograde amnesia and seizures. Brain MRI revealed bilateral lesions of medial temporal lobes. Screening for anti-neuronal antibodies showed high anti-GAD titers in both serum and cerebrospinal fluid (CSF) with strong evidence of intrathecal production. The patient received treatment with prednisolone and long-term plasma exchange. During a 12-month follow-up, she exhibited complete seizure remission and an improvement in memory and visuo-spatial skills. Anti-GAD antibodies may serve as a useful marker to identify a subset of NPLE patients that respond to immunoregulatory treatment.

  14. Regulation of human ornithine decarboxylase expression by the c-Myc.Max protein complex.

    Science.gov (United States)

    Peña, A; Reddy, C D; Wu, S; Hickok, N J; Reddy, E P; Yumet, G; Soprano, D R; Soprano, K J

    1993-12-25

    The presence of a CACGTG element within a region of the human ornithine decarboxylase (ODC) promoter located at -491 to -474 base pairs 5' to the start site of transcription suggested that the c-Myc.Max protein complex may play a role in the regulation of ODC expression during growth. Electrophoretic mobility shift assays and methylation interference analysis showed that the nuclei of WI-38 cells expressing ODC contained proteins that bound to this region of the ODC gene in a manner that correlated with growth-associated ODC expression. Also, use of antibodies against c-Myc and Max and purified recombinant c-Myc and Max protein in the electrophoretic mobility shift assay confirmed that these proteins can specifically bind this portion of the human ODC promoter. Transient transfection studies showed that increase in the level of c-Myc and/or Max led to a significant enhancement of expression of a human ODC promoter-CAT reporter construct. Moreover, treatment of actively growing WI-38 cells with an antisense oligomer to c-Myc reduced the amount of endogenous protein complex formed and the amount of endogenous ODC mRNA expressed. These studies show that the c-Myc.Max protein complex plays a role in the transcriptional regulation of human ODC in vivo.

  15. Aversive odorant causing appetite decrease downregulates tyrosine decarboxylase gene expression in the olfactory receptor neuron of the blowfly, Phormia regina

    Science.gov (United States)

    Ishida, Yuko; Ozaki, Mamiko

    2012-01-01

    In the blowfly Phormia regina, exposure to d-limonene for 5 days during feeding inhibits proboscis extension reflex behavior due to decreasing tyramine (TA) titer in the brain. TA is synthesized by tyrosine decarboxylase (Tdc) and catalyzed into octopamine (OA) by TA ß-hydroxylase (Tbh). To address the mechanisms of TA titer regulation in the blowfly, we cloned Tdc and Tbh cDNAs from P. regina (PregTdc and PregTbh). The deduced amino acid sequences of both proteins showed high identity to those of the corresponding proteins from Drosophila melanogaster at the amino acid level. PregTdc was expressed in the antenna, labellum, and tarsus whereas PregTbh was expressed in the head, indicating that TA is mainly synthesized in the sensory organs whereas OA is primarily synthesized in the brain. d-Limonene exposure significantly decreased PregTdc expression in the antenna but not in the labellum and the tarsus, indicating that PregTdc expressed in the antenna is responsible for decreasing TA titer. PregTdc-like immunoreactive material was localized in the thin-walled sensillum. In contrast, the OA/TA receptor (PregOAR/TAR) was localized to the thick-walled sensillum. The results indicated that d-limonene inhibits PregTdc expression in the olfactory receptor neurons in the thin-walled sensilla, likely resulting in reduced TA levels in the receptor neurons in the antenna. TA may be transferred from the receptor neuron to the specific synaptic junction in the antennal lobe of the brain through the projection neurons and play a role in conveying the aversive odorant information to the projection and local neurons.

  16. Ornithine decarboxylase expression in the small intestine of broilers submitted to feed restriction and glutamine supplementation

    Directory of Open Access Journals (Sweden)

    AV Fischer da Silva

    2007-06-01

    Full Text Available Six hundred and forty one-day-old Cobb male broilers were used to evaluate ornithine decarboxylase (ODC expression in the mucosa of the small intestine. Birds were submitted to early feed restriction from 7 to 14 days of age. The provided feed was supplemented with glutamine. A completely randomized design with a 2 x 2 factorial arrangement was used (with or without glutamine, with or without feed restriction. Restricted-fed birds were fed at 30% the amount of the ad libitum fed group from 7 to 14 days of age. Glutamine was added at the level of 1% in the diet supplied from 1 to 28 days of age. Protein concentration in the small intestine mucosa was determined, and ODC expression at 7, 14, 21, and 28 days of age was evaluated by dot blotting. ODC was present in the mucosa of broilers, and the presence of glutamine in the diet increased ODC activation. Glutamine prevented mucosa atrophy by stimulating protein synthesis, and was effective against the effects of feed restriction. Dot blotting can be used to quantify ODC expression in the intestinal mucosa of broilers.

  17. Characterization of the activity and expression of arginine decarboxylase in human and animal Chlamydia pathogens.

    Science.gov (United States)

    Bliven, Kimberly A; Fisher, Derek J; Maurelli, Anthony T

    2012-12-01

    Chlamydia pneumoniae encodes a functional arginine decarboxylase (ArgDC), AaxB, that activates upon self-cleavage and converts l-arginine to agmatine. In contrast, most Chlamydia trachomatis serovars carry a missense or nonsense mutation in aaxB abrogating activity. The G115R missense mutation was not predicted to impact AaxB functionality, making it unclear whether AaxB variations in other Chlamydia species also result in enzyme inactivation. To address the impact of gene polymorphism on functionality, we investigated the activity and production of the Chlamydia AaxB variants. Because ArgDC plays a critical role in the Escherichia coli acid stress response, we studied the ability of these Chlamydia variants to complement an E. coli ArgDC mutant in an acid shock assay. Active AaxB was detected in four additional species: Chlamydia caviae, Chlamydia pecorum, Chlamydia psittaci, and Chlamydia muridarum. Of the C. trachomatis serovars, only E appears to encode active enzyme. To determine when functional enzyme is present during the chlamydial developmental cycle, we utilized an anti-AaxB antibody to detect both uncleaved and cleaved enzyme throughout infection. Uncleaved enzyme production peaked around 20 h postinfection, with optimal cleavage around 44 h. While the role ArgDC plays in Chlamydia survival or virulence is unclear, our data suggest a niche-specific function.

  18. Crystal Structures of Apo and Liganded 4-Oxalocrotonate Decarboxylase Uncover a Structural Basis for the Metal-Assisted Decarboxylation of a Vinylogous β-Keto Acid.

    Science.gov (United States)

    Guimarães, Samuel L; Coitinho, Juliana B; Costa, Débora M A; Araújo, Simara S; Whitman, Christian P; Nagem, Ronaldo A P

    2016-05-10

    The enzymes in the catechol meta-fission pathway have been studied for more than 50 years in several species of bacteria capable of degrading a number of aromatic compounds. In a related pathway, naphthalene, a toxic polycyclic aromatic hydrocarbon, is fully degraded to intermediates of the tricarboxylic acid cycle by the soil bacteria Pseudomonas putida G7. In this organism, the 83 kb NAH7 plasmid carries several genes involved in this biotransformation process. One enzyme in this route, NahK, a 4-oxalocrotonate decarboxylase (4-OD), converts 2-oxo-3-hexenedioate to 2-hydroxy-2,4-pentadienoate using Mg(2+) as a cofactor. Efforts to study how 4-OD catalyzes this decarboxylation have been hampered because 4-OD is present in a complex with vinylpyruvate hydratase (VPH), which is the next enzyme in the same pathway. For the first time, a monomeric, stable, and active 4-OD has been expressed and purified in the absence of VPH. Crystal structures for NahK in the apo form and bonded with five substrate analogues were obtained using two distinct crystallization conditions. Analysis of the crystal structures implicates a lid domain in substrate binding and suggests roles for specific residues in a proposed reaction mechanism. In addition, we assign a possible function for the NahK N-terminal domain, which differs from most of the other members of the fumarylacetoacetate hydrolase superfamily. Although the structural basis for metal-dependent β-keto acid decarboxylases has been reported, this is the first structural report for that of a vinylogous β-keto acid decarboxylase and the first crystal structure of a 4-OD.

  19. Danish children born with glutamic acid decarboxylase-65 and islet antigen-2 autoantibodies at birth had an increased risk to develop type 1 diabetes

    DEFF Research Database (Denmark)

    Eising, Stefanie; Nilsson, Anita; Carstensen, Bendix;

    2011-01-01

    A large, population-based case-control cohort was used to test the hypothesis that glutamic acid decarboxylase-65 (GAD65) and islet antigen-2 autoantibodies (IA-2A) at birth predict type 1 diabetes.......A large, population-based case-control cohort was used to test the hypothesis that glutamic acid decarboxylase-65 (GAD65) and islet antigen-2 autoantibodies (IA-2A) at birth predict type 1 diabetes....

  20. Overexpression and optimization of glutamate decarboxylase in Lactobacillus plantarum Taj-Apis362 for high gamma-aminobutyric acid production.

    Science.gov (United States)

    Tajabadi, Naser; Baradaran, Ali; Ebrahimpour, Afshin; Rahim, Raha A; Bakar, Fatimah A; Manap, Mohd Yazid A; Mohammed, Abdulkarim S; Saari, Nazamid

    2015-07-01

    Gamma-aminobutyric acid (GABA) is an important bioactive compound biosynthesized by microorganisms through decarboxylation of glutamate by glutamate decarboxylase (GAD). In this study, a full-length GAD gene was obtained by cloning the template deoxyribonucleic acid to pTZ57R/T vector. The open reading frame of the GAD gene showed the cloned gene was composed of 1410 nucleotides and encoded a 469 amino acids protein. To improve the GABA-production, the GAD gene was cloned into pMG36e-LbGAD, and then expressed in Lactobacillus plantarum Taj-Apis362 cells. The overexpression was confirmed by SDS-PAGE and GAD activity, showing a 53 KDa protein with the enzyme activity increased by sevenfold compared with the original GAD activity. The optimal fermentation conditions for GABA production established using response surface methodology were at glutamic acid concentration of 497.973 mM, temperature 36°C, pH 5.31 and time 60 h. Under the conditions, maximum GABA concentration obtained (11.09 mM) was comparable with the predicted value by the model at 11.23 mM. To our knowledge, this is the first report of successful cloning (clone-back) and overexpression of the LbGAD gene from L. plantarum to L. plantarum cells. The recombinant Lactobacillus could be used as a starter culture for direct incorporation into a food system during fermentation for production of GABA-rich products.

  1. Aromatic Amino Acid Decarboxylase Deficiency Not Responding to Pyridoxine and Bromocriptine Therapy: Case Report and Review of Response to Treatment

    OpenAIRE

    2014-01-01

    Aromatic L-amino acid decarboxylase (AADC) deficiency (MIM #608643) is an autosomal recessive inborn error of monoamines. It is caused by a mutation in the DDC gene that leads to a deficiency in the AADC enzyme. The clinical features of this condition include a combination of dopamine, noradrenaline, and serotonin deficiencies, and a patient may present with hypotonia, oculogyric crises, sweating, hypersalivation, autonomic dysfunction, and progressive encephalopathy with severe developmental...

  2. Cloning and molecular characterization of an ornithine decarboxylase gene and its expression during embryonic development of the housefly, Musca domestica.

    Science.gov (United States)

    Toutges, Michelle J; Santoso, Adi

    2011-10-01

    We are interested in identifying targets that may be used to develop new control products for the common housefly, Musca domestica, a vector of disease for many vertebrates. One such target, ornithine decarboxylase (ODC), is an embryonic enzyme involved in the regulation of polyamines and is a critical enzyme during M. domestica development. In this study, the cDNA for ODC from M. domestica was cloned, sequenced, and characterized. The full-length cDNA was 1,337-bp, consistent with a single band of approximately 1.35 kb obtained by northern analysis. The open-reading frame contains 1,191 bp, yielding a deduced polypeptide of 396 amino acid residues with a predicted mass of 44,618 Da. The deduced M. domestica ODC protein was homologous to other ODC proteins. mRNA expression profiles analyzed by real-time PCR indicated that the ODC transcript is temporally regulated throughout embryogenesis. Sequence data and Southern blot analysis suggests that there were likely only one or two closely linked copies of the M. domestica ODC gene.

  3. Developmental changes of glutamate acid decarboxylase 67 in mouse brain after hypoxia ischemia

    Institute of Scientific and Technical Information of China (English)

    Fa-Lin XU; Chang-Lian ZHU; Xiao-Yang WANG

    2006-01-01

    Objective To study the developmental changes of glutamic acid decarboxylase-67 ( GAD-67, a GABA synthetic enzyme) in normal and hypoxic ischemic (HI) brain. Methods C57/BL6 mice on postnatal day (P) 5, 9, 21and 60, corresponding developmentally to premature, term, juvenile and adult human brain were investigated by using both Western blot and immunohistochemistry methods either in normal condition or after hypoxic ischemic insult. Results The immunoreactivity of GAD67 was up regulated with brain development and significant difference was seen between mature (P21, P60) and immature (P5, P9) brain. GAD67 immunoreactivity decreased in the ipsilateral hemisphere in all the ages after hypoxia ischemia (HI) insult, but, significant decrease was only seen in the immature brain. Double labeling of GAD67 and cell death marker, TUNEL, in the cortex at 8h post-HI in the P9 mice showed that (15.6 ±7.0)%TUNEL positive cells were GAD67 positive which was higher than that of P60 mice. Conclusion These data suggest that GABAergic neurons in immature brain were more vulnerable to HI insult than that of mature brain.

  4. Aromatic L-amino acid decarboxylase deficiency diagnosed by clinical metabolomic profiling of plasma.

    Science.gov (United States)

    Atwal, Paldeep S; Donti, Taraka R; Cardon, Aaron L; Bacino, C A; Sun, Qin; Emrick, L; Reid Sutton, V; Elsea, Sarah H

    2015-01-01

    Aromatic L-amino acid decarboxylase (AADC) deficiency is an inborn error of metabolism affecting the biosynthesis of serotonin, dopamine, and catecholamines. We report a case of AADC deficiency that was detected using the Global MAPS platform. This is a novel platform that allows for parallel clinical testing of hundreds of metabolites in a single plasma specimen. It uses a state-of-the-art mass spectrometry platform, and the resulting spectra are compared against a library of ~2500 metabolites. Our patient is now a 4 year old boy initially seen at 11 months of age for developmental delay and hypotonia. Multiple tests had not yielded a diagnosis until exome sequencing revealed compound heterozygous variants of uncertain significance (VUS), c.286G>A (p.G96R) and c.260C>T (p.P87L) in the DDC gene, causal for AADC deficiency. CSF neurotransmitter analysis confirmed the diagnosis with elevated 3-methoxytyrosine (3-O-methyldopa). Metabolomic profiling was performed on plasma and revealed marked elevation in 3-methoxytyrosine (Z-score +6.1) consistent with the diagnosis of AADC deficiency. These results demonstrate that the Global MAPS platform is able to diagnose AADC deficiency from plasma. In summary, we report a novel and less invasive approach to diagnose AADC deficiency using plasma metabolomic profiling.

  5. 水杨酸钠对幼年和成年豚鼠听性脑干反应阈值及螺旋神经节谷氨酸脱羧酶表达的影响%Effect of sodium salicylate on the auditory brain stem response threshold and expression of glutamic acid decarboxylase in spiral ganglion of juvenile and adult guinea pigs

    Institute of Scientific and Technical Information of China (English)

    尹时华; 唐安洲; 谭颂华; 陈平; 谢利红; 任毅

    2008-01-01

    目的 观察水杨酸钠对幼年和成年豚鼠听性脑干反应(ABR)阈值以及螺旋神经节谷氨酸脱羧酶(glutamic acid decarboxylase,GAD)表达的影响.方法 选择出生4 d的豚鼠40只和出生后1个月的成年豚鼠40只,分成4组(每组20只):幼年对照组,成年对照组,幼年水杨酸钠给药组[300 mg/(kg·d)],成年水杨酸钠给药组[300 mg/(kg·d)].给药15 d后每组随机选取10只豚鼠检测ABR阈值,采用免疫组织化学染色方法检测螺旋神经节GAD的表达.各组剩下的动物停止给药,继续喂养30 d后检测ABR阈值和螺旋神经节GAD的表达.结果 给药15 d后幼年水杨酸钠给药组和成年水杨酸钠给药组豚鼠ABR阈值较给药前以及同期对照组均有提高(P值均<0.001),停药30 d后幼年水杨酸钠给药组ABR阈值恢复到给药前水平,而成年水杨酸钠给药组仍停留在高阈值水平;水杨酸钠给药15 d后能明显下调幼年以及成年豚鼠螺旋神经节GAD蛋白表达,幼年豚鼠GAD表达水平低于成年豚鼠(t=4.7,P<0.001),停药30 d后幼年给药组螺旋神经节GAD表达恢复到同期对照组水平,而成年给药组则继续停留在低表达水平.结论 水杨酸钠在对幼年和成年豚鼠ABR阚值以及螺旋神经节GAD表达的影响上存在差异,其对幼年豚鼠的影响更为明显,但停药后幼年豚鼠较成年豚鼠更容易恢复到正常水平.%Objective To study the differences of regulation of sodium salicylate on the auditory brain stem response(ABR)threshold and expression of glutamic acid decarboxylase(GAD)protein in spiral ganglion of juvenile and adult guinea pigs.Methods Fourty juvenile guinea pigs which were born just four days and fourty adult guinea pigs which were born thirty days were selected.They were divided four groups (group A;group B;group C;group D).ABR threshold was detected before administration.after administration for 15 days and after administration stopped for 30 days.The protein expression of GAD

  6. Rapid detection and quantification of tyrosine decarboxylase gene (tdc) and its expression in gram-positive bacteria associated with fermented foods using PCR-based methods.

    Science.gov (United States)

    Torriani, Sandra; Gatto, Veronica; Sembeni, Silvia; Tofalo, Rosanna; Suzzi, Giovanna; Belletti, Nicoletta; Gardini, Fausto; Bover-Cid, Sara

    2008-01-01

    In this study, PCR-based procedures were developed to detect the occurrence and quantify the expression of the tyrosine decarboxylase gene (tdc) in gram-positive bacteria associated with fermented foods. Consensus primers were used in conventional and reverse transcription PCR to analyze a collection of 87 pure cultures of lactic acid bacteria and staphylococci. All enterococci, Staphylococcus epidermidis, Lactobacillus brevis, Lactobacillus curvatus, and Lactobacillus fermentum strains and 1 of 10 Staphylococcus xylosus strains produced amplification products with the primers DEC5 and DEC3 in accordance with results of the screening plate method and with previously reported result obtained with high-performance liquid chromatography. No amplicons were obtained for tyramine-negative strains, confirming the high specificity of these new primers. A novel quantitative real-time PCR assay was successfully applied to quantify tdc and its transcript in pure cultures and in meat and meat products. This assay allowed estimation of the influence of different variables (pH, temperature, and NaCl concentration) on the tdc expression of the tyraminogenic strain Enterococcus faecalis EF37 after 72 h of growth in M17 medium. Data obtained suggest that stressful conditions could induce greater tyrosine decarboxylase activity. The culture-independent PCR procedures developed here may be used for reliable and fast detection and quantification of bacterial tyraminogenic activity without the limitations of conventional techniques.

  7. Sequential elevation of autoantibodies to thyroglobulin and glutamic acid decarboxylase in type 1 diabetes

    Institute of Scientific and Technical Information of China (English)

    Eiji; Kawasaki; Jun-ichi; Yasui; Masako; Tsurumaru; Haruko; Takashima; Toshiyuki; Ikeoka; Fumi; Mori; Satoru; Akazawa; Ikuko; Ueki; Masakazu; Kobayashi; Hironaga; Kuwahara; Norio; Abiru; Hironori; Yamasaki; Atsushi; Kawakami

    2013-01-01

    We have previously reported the high levels of glutamic acid decarboxylase 65 autoantibodies(GAD65A)in patients with type 1 diabetes and autoimmune thyroid disease.Here we describe a 32-year-old Japanese female with a thirteen-year history of type 1 diabetes whose levels of GAD65A were elevated just after the emergence of anti-thyroid autoimmunity.At 19 years of age,she developed diabetic ketoacidosis and was diagnosed with type 1 diabetes.She had GAD65A,insulinoma-associated antigen-2 autoantibodies(IA-2A),and zinc transporter-8 autoantibodies(ZnT8A),but was negative for antibodies to thyroid peroxidase(TPOAb)and thyroglobulin(TGAb)at disease onset.ZnT8A and IA-2A turned negative 2-3 years after the onset,whereas GAD65A were persistently positive at lower level(approximately 40 U/mL).However,just after the emergence of TGAb at disease duration of 12.5 years,GAD65A levels were reelevated up to5717 U/mL in the absence of ZnT8A and IA-2A.Her thyroid function was normal and TPOAb were consistently negative.She has a HLA-DRB1*03:01/*04:01-DQB1*02:01/*03:02 genotype.Persistent positivity for GAD65A might be associated with increased risk to develop anti-thyroid autoimmunity.

  8. Glutamic acid decarboxylase 65 autoantibody levels discriminate two subtypes of latent autoimmune diabetes in adults

    Institute of Scientific and Technical Information of China (English)

    李霞; 杨琳; 周智广; 黄干; 颜湘

    2003-01-01

    Objective To compare the clinical characteristics between type 2 diabetes mellitus (T2DM) and latent autoimmune diabetes in adults (LADA) with different titers of glutamic acid decarboxylase autoantibody (GADA) and to define the two distinct subtypes of LADA.Methods Sera of 750 patients with an initial diagnosis of T2DM from central south of China were screened for GADA using a radioligand assay. The distribution and frequency of GADA levels were described. Two hundred and ninety-five patients were divided into the T2DM group (n=233) and the LADA group (n=62) to compare the age of onset, body mass index, HbA1c, C-peptide, hypertension, dyslipidemia and chronic diabetic complications. Furthermore, LADA patients with different GADA titers were subdivided to analyze the same indexes as the above. Results The prevalence of LADA (defined as GADA≥0.05, namely GADA positive) was 9.7% in the 750 initially diagnosed type 2 diabetic patients. Compared with T2DM, LADA patients were younger at their ages of onset, had lower C-peptide and body mass index, and also had less cases with hypertension and with dyslipidemia. However, only patients with high titer of GADA had poorer beta cell functions and less diabetic complications compared to T2DM and low GADA titer of LADA patients. Patients with low GADA titer were similar to T2DM patients, except that they were prone to develop ketosis more frequently.Conclusions Two clinically distinct subtypes of LADA can be identified by GADA levels in patients initially-diagnosed as type 2 diabetes. Patients with high titer of GADA (GADA≥0.5) subsequently develop more insulin dependency, which are classified as LADA-type 1; while those with lower GADA titer (0.05≤GADA<0.5) and having clinical and metabolic phenotypes of type 2 diabetes are classified as LADA-type 2.

  9. Serotonin accumulation in transgenic rice by over-expressing tryptophan decarboxylase results in a dark brown phenotype and stunted growth.

    Science.gov (United States)

    Kanjanaphachoat, Parawee; Wei, Bi-Yin; Lo, Shuen-Fang; Wang, I-Wen; Wang, Chang-Sheng; Yu, Su-May; Yen, Ming-Liang; Chiu, Sheng-Hsien; Lai, Chien-Chen; Chen, Liang-Jwu

    2012-04-01

    A mutant M47286 with a stunted growth, low fertility and dark-brown phenotype was identified from a T-DNA-tagged rice mutant library. This mutant contained a copy of the T-DNA tag inserted at the location where the expression of two putative tryptophan decarboxylase genes, TDC-1 and TDC-3, were activated. Enzymatic assays of both recombinant proteins showed tryptophan decarboxylase activities that converted tryptophan to tryptamine, which could be converted to serotonin by a constitutively expressed tryptamine 5' hydroxylase (T5H) in rice plants. Over-expression of TDC-1 and TDC-3 in transgenic rice recapitulated the stunted growth, darkbrown phenotype and resulted in a low fertility similar to M47286. The degree of stunted growth and dark-brown color was proportional to the expression levels of TDC-1 and TDC-3. The levels of tryptamine and serotonin accumulation in these transgenic rice lines were also directly correlated with the expression levels of TDC-1 and TDC-3. A mass spectrometry assay demonstrated that the darkbrown leaves and hulls in the TDC-overexpressing transgenic rice were caused by the accumulation of serotonin dimer and that the stunted growth and low fertility were also caused by the accumulation of serotonin and serotonin dimer, but not tryptamine. These results represent the first evidence that over-expression of TDC results in stunted growth, low fertility and the accumulation of serotonin, which when converted to serotonin dimer, leads to a dark brown plant color.

  10. 经皮三叉神经电刺激预处理对戊四氮致痫大鼠海马谷氨酸脱羧酶表达的影响%Effects of pretreatment with transcutaneous trigeminal nerve electrostimulation on expression of glutamic acid decarboxylase in rat hippocampus with pentetrazol-induced seizures

    Institute of Scientific and Technical Information of China (English)

    张慧敏; 李良勇; 李家林; 王玉

    2011-01-01

    Objective To observe the effects of pretreatment with transcutaneous trigeminal nerve electrostimulation ( TNS ) on expression of glutamic acid decarboxylase( GAD )65/67 in rat hippocampus with pentetrazol-induced seizures and explone its possible anti-epileptic mechanisms. Methods Rats were divided into control group and TNS group which were given pentetrazol( PTZ ) after I ,7.14,28 d consecutive electrostimulation respectively, and subsequently the severity of seizure was quantitatively evaluated within 2 h after intraperitoneal injection of PTZ. The GAD65 and CAD67 protein was analyzed by immunohistochemistry at different time quantitatively in the regions of hippocampus. Results ① Compared with the corresponding control group, the severity of seizure in 14 d and 28 d consecutive TNS groups was significantly milder ( P <0. 05 ), while in I d and 7 d groups, little but no significant change was observed ( P>0. 05 ).② Compared with the corresponding control group, the number of GAD65 posi tive cells in hippocampus was significantly increased in the 7 , 14 ,28 d TNS groups ( P 0.05),TNS组连续刺激14、28 d大鼠癫痫发作程度明显减轻(P0.05),TNS组7、14、28 d大鼠海马区GAD65表达数目明显增加(P<0.05),并且随刺激时间延长,GAD65阳性细胞增加越明显.③ 与相应时间点对照组比较,TNS各组GAD67阳性细胞光密度差异均有统计学意义(P<0.05),但表达增加与刺激时间长短无明显关系.结论 经皮TNS预处理对癫痫发作有一定影响,可能与海马区内GAD65和GAD67阳性表达增多,进而诱导脑内抑制性机制的增强有关.

  11. HosA, a MarR Family Transcriptional Regulator, Represses Nonoxidative Hydroxyarylic Acid Decarboxylase Operon and Is Modulated by 4-Hydroxybenzoic Acid.

    Science.gov (United States)

    Roy, Ajit; Ranjan, Akash

    2016-02-23

    Members of the Multiple antibiotic resistance Regulator (MarR) family of DNA binding proteins regulate transcription of a wide array of genes required for virulence and pathogenicity of bacteria. The present study reports the molecular characterization of HosA (Homologue of SlyA), a MarR protein, with respect to its target gene, DNA recognition motif, and nature of its ligand. Through a comparative genomics approach, we demonstrate that hosA is in synteny with nonoxidative hydroxyarylic acid decarboxylase (HAD) operon and is present exclusively within the mutS-rpoS polymorphic region in nine different genera of Enterobacteriaceae family. Using molecular biology and biochemical approach, we demonstrate that HosA binds to a palindromic sequence downstream to the transcription start site of divergently transcribed nonoxidative HAD operon and represses its expression. Furthermore, in silico analysis showed that the recognition motif for HosA is highly conserved in the upstream region of divergently transcribed operon in different genera of Enterobacteriaceae family. A systematic chemical search for the physiological ligand revealed that 4-hydroxybenzoic acid (4-HBA) interacts with HosA and derepresses HosA mediated repression of the nonoxidative HAD operon. Based on our study, we propose a model for molecular mechanism underlying the regulation of nonoxidative HAD operon by HosA in Enterobacteriaceae family.

  12. Structural basis of enzymatic activity for the ferulic acid decarboxylase (FADase from Enterobacter sp. Px6-4.

    Directory of Open Access Journals (Sweden)

    Wen Gu

    Full Text Available Microbial ferulic acid decarboxylase (FADase catalyzes the transformation of ferulic acid to 4-hydroxy-3-methoxystyrene (4-vinylguaiacol via non-oxidative decarboxylation. Here we report the crystal structures of the Enterobacter sp. Px6-4 FADase and the enzyme in complex with substrate analogues. Our analyses revealed that FADase possessed a half-opened bottom β-barrel with the catalytic pocket located between the middle of the core β-barrel and the helical bottom. Its structure shared a high degree of similarity with members of the phenolic acid decarboxylase (PAD superfamily. Structural analysis revealed that FADase catalyzed reactions by an "open-closed" mechanism involving a pocket of 8 × 8 × 15 Å dimension on the surface of the enzyme. The active pocket could directly contact the solvent and allow the substrate to enter when induced by substrate analogues. Site-directed mutagenesis showed that the E134A mutation decreased the enzyme activity by more than 60%, and Y21A and Y27A mutations abolished the enzyme activity completely. The combined structural and mutagenesis results suggest that during decarboxylation of ferulic acid by FADase, Trp25 and Tyr27 are required for the entering and proper orientation of the substrate while Glu134 and Asn23 participate in proton transfer.

  13. Consistency of polyamine profiles and expression of arginine decarboxylase in mitosis during zygotic embryogenesis of Scots pine.

    Science.gov (United States)

    Vuosku, Jaana; Jokela, Anne; Läärä, Esa; Sääskilahti, Mira; Muilu, Riina; Sutela, Suvi; Altabella, Teresa; Sarjala, Tytti; Häggman, Hely

    2006-11-01

    In this study, we show that both arginine decarboxylase (ADC) protein and mRNA transcript are present at different phases of mitosis in Scots pine (Pinus sylvestris) zygotic embryogenesis. We also examined the consistency of polyamine (PA) profiles with the effective temperature sum, the latter indicating the developmental stage of the embryos. PA metabolism was analyzed by fitting statistical regression models to the data of free and soluble conjugated PAs, to the enzyme activities of ADC and ornithine decarboxylase (ODC), as well as to the gene expression of ADC. According to the fitted models, PAs typically had the tendency to increase at the early stages but decrease at the late stages of embryogenesis. Only the free putrescine fraction remained stable during embryo development. The PA biosynthesis strongly preferred the ADC pathway. Both ADC gene expression and ADC enzyme activity were substantially higher than putative ODC gene expression or ODC enzyme activity, respectively. ADC gene expression and enzyme activity increased during embryogenesis, which suggests the involvement of transcriptional regulation in the expression of ADC. Both ADC mRNA and ADC protein localized in dividing cells of embryo meristems and more specifically within the mitotic spindle apparatus and close to the chromosomes, respectively. The results suggest the essential role of ADC in the mitosis of plant cells.

  14. The application of glutamic acid alpha-decarboxylase for the valorization of glutamic acid

    NARCIS (Netherlands)

    Lammens, T.M.; Biase, De Daniela; Franssen, M.C.R.; Scott, E.L.; Sanders, J.P.M.

    2009-01-01

    Glutamic acid is an important constituent of waste streams from biofuels production. It is an interesting starting material for the synthesis of nitrogen containing bulk chemicals, thereby decreasing the dependency on fossil fuels. On the pathway from glutamic acid to a range of molecules, the decar

  15. The UDP-glucuronate decarboxylase gene family in Populus: structure, expression, and association genetics.

    Directory of Open Access Journals (Sweden)

    Qingzhang Du

    Full Text Available In woody crop plants, the oligosaccharide components of the cell wall are essential for important traits such as bioenergy content, growth, and structural wood properties. UDP-glucuronate decarboxylase (UXS is a key enzyme in the synthesis of UDP-xylose for the formation of xylans during cell wall biosynthesis. Here, we isolated a multigene family of seven members (PtUXS1-7 encoding UXS from Populus tomentosa, the first investigation of UXSs in a tree species. Analysis of gene structure and phylogeny showed that the PtUXS family could be divided into three groups (PtUXS1/4, PtUXS2/5, and PtUXS3/6/7, consistent with the tissue-specific expression patterns of each PtUXS. We further evaluated the functional consequences of nucleotide polymorphisms in PtUXS1. In total, 243 single-nucleotide polymorphisms (SNPs were identified, with a high frequency of SNPs (1/18 bp and nucleotide diversity (πT = 0.01033, θw = 0.01280. Linkage disequilibrium (LD analysis showed that LD did not extend over the entire gene (r (2<0.1, P<0.001, within 700 bp. SNP- and haplotype-based association analysis showed that nine SNPs (Q <0.10 and 12 haplotypes (P<0.05 were significantly associated with growth and wood property traits in the association population (426 individuals, with 2.70% to 12.37% of the phenotypic variation explained. Four significant single-marker associations (Q <0.10 were validated in a linkage mapping population of 1200 individuals. Also, RNA transcript accumulation varies among genotypic classes of SNP10 was further confirmed in the association population. This is the first comprehensive study of the UXS gene family in woody plants, and lays the foundation for genetic improvements of wood properties and growth in trees using genetic engineering or marker-assisted breeding.

  16. Glutamic acid decarboxylase-67-positive hippocampal interneurons undergo a permanent reduction in number following kainic acid-induced degeneration of ca3 pyramidal neurons.

    Science.gov (United States)

    Shetty, A K; Turner, D A

    2001-06-01

    Kainic acid (KA)-induced degeneration of CA3 pyramidal neurons leads to synaptic reorganization and hyperexcitability in both dentate gyrus and CA1 region of the hippocampus. We hypothesize that the substrate for hippocampal inhibitory circuitry incurs significant and permanent alterations following degeneration of CA3 pyramidal neurons. We quantified changes in interneuron density (N(v)) in all strata of the dentate gyrus and the CA1 and CA3 subfields of adult rats at 1, 4, and 6 months following intracerebroventricular (icv) KA administration, using glutamic acid decarboxylase-67 (GAD-67) immunocytochemistry. At 1 month postlesion, GAD-67-positive interneuron density was significantly reduced in all strata of every hippocampal region except stratum pyramidale of CA1. The reduction in GAD-67-positive interneuron density either persisted or exacerbated at 4 and 6 months postlesion in every stratum of all hippocampal regions. Further, the soma of remaining GAD-67-positive interneurons in dentate gyrus and CA3 subfield showed significant hypertrophy. Thus, both permanent reductions in the density of GAD-67-positive interneurons in all hippocampal regions and somatic hypertrophy of remaining GAD-67-positive interneurons in dentate gyrus and CA3 subfield occur following icv KA. In contrast, the density of interneurons visualized with Nissl in CA1 and CA3 regions was nearly equivalent to that in the intact hippocampus at all postlesion time points. Collectively, these results suggest that persistent reductions in GAD-67-positive interneuron density observed throughout the hippocampus following CA3 lesion are largely due to a permanent loss of GAD-67 expression in a significant fraction of interneurons, rather than widespread degeneration of interneurons. Nevertheless, a persistent decrease in interneuron activity, as evidenced by permanent down-regulation of GAD-67 in a major fraction of interneurons, would likely enhance the degree of hyperexcitability in the CA3

  17. Glutamic acid decarboxylase autoantibody-positivity post-partum is associated with impaired β-cell function in women with gestational diabetes mellitus

    DEFF Research Database (Denmark)

    Lundberg, T. P.; Højlund, K.; Snogdal, L. S.;

    2015-01-01

    AIMS: To investigate whether the presence of glutamic acid decarboxylase (GAD) autoantibodies post-partum in women with prior gestational diabetes mellitus was associated with changes in metabolic characteristics, including β-cell function and insulin sensitivity. METHODS: During 1997-2010, 407...

  18. Spinal cord hemisection facilitates aromatic L-amino acid decarboxylase cells to produce serotonin in the subchronic but not the chronic phase

    DEFF Research Database (Denmark)

    Azam, Bushra; Wienecke, Jacob; Jensen, Dennis Bo

    2015-01-01

    Neuromodulators, such as serotonin (5-hydroxytryptamine, 5-HT) and noradrenalin, play an essential role in regulating the motor and sensory functions in the spinal cord. We have previously shown that in the rat spinal cord the activity of aromatic L-amino acid decarboxylase (AADC) cells to produce...

  19. Distribution of glutamic acid decarboxylase messenger RNA-containing nerve cell populations of the male rat brain.

    Science.gov (United States)

    Ferraguti, F; Zoli, M; Aronsson, M; Agnati, L F; Goldstein, M; Filer, D; Fuxe, K

    1990-01-01

    The distribution of glutamic acid decarboxylase (GAD) mRNA was investigated throughout the rat brain by means of in situ hybridization. Hybridization was carried out with a 35S-radiolabeled cRNA probe transcribed from a cDNA from cat occipital cortex and cloned in a SP6-T7 promoter-containing vector. Fixed tissue sections were hybridized with 35S GAD probe (0.6 kb length). Signal was detected by means of film or emulsion autoradiography. The autoradiograms were semiquantitatively evaluated by means of computer-assisted image analysis. The results obtained with this evaluation were correlated with the results of the semiquantitative analysis of GAD immunoreactivity performed by Mugnaini and Oertel. Specific labeling was only observed in neuronal cell bodies, whereas no labeling was found over neuropil, glial and endothelial cells. The highest labeling was found in the bulbus olfactorius (internal plexiform and granular layers) and in the caudal magnocellular nucleus of the hypothalamus. Strong labeling was observed in the Purkinje layer of the cerebellar cortex, the interpeduncular nucleus, the interstitial nucleus of Cajal, the nucleus of Darkschewitsch and the suprachiasmatic nucleus. Intermediate or low levels of GAD mRNA were present in various brain nuclei, where gamma-aminobutyric acid (GABA)-containing cell bodies had been observed with other techniques. Interestingly, a low level of GAD mRNA was found in the caudate-putamen and nucleus accumbens, where the vast majority of nerve cells is known to contain GAD immunoreactivity. Only a poor correlation was found between the present semiquantitative measurements of GAD mRNA content and previous analyses of the number of GAD-immunoreactive cell bodies. The present study demonstrates that there exists a differential regional expression of GAD mRNA. The comparison with cell counts performed by immunocytochemistry suggests that some brain areas, such as caudate-putamen and nucleus accumbens, contain a large number

  20. High-yield production of vanillin from ferulic acid by a coenzyme-independent decarboxylase/oxygenase two-stage process.

    Science.gov (United States)

    Furuya, Toshiki; Miura, Misa; Kuroiwa, Mari; Kino, Kuniki

    2015-05-25

    Vanillin is one of the world's most important flavor and fragrance compounds in foods and cosmetics. Recently, we demonstrated that vanillin could be produced from ferulic acid via 4-vinylguaiacol in a coenzyme-independent manner using the decarboxylase Fdc and the oxygenase Cso2. In this study, we investigated a new two-pot bioprocess for vanillin production using the whole-cell catalyst of Escherichia coli expressing Fdc in the first stage and that of E. coli expressing Cso2 in the second stage. We first optimized the second-step Cso2 reaction from 4-vinylguaiacol to vanillin, a rate-determining step for the production of vanillin. Addition of FeCl2 to the cultivation medium enhanced the activity of the resulting E. coli cells expressing Cso2, an iron protein belonging to the carotenoid cleavage oxygenase family. Furthermore, a butyl acetate-water biphasic system was effective in improving the production of vanillin. Under the optimized conditions, we attempted to produce vanillin from ferulic acid by a two-pot bioprocess on a flask scale. In the first stage, E. coli cells expressing Fdc rapidly decarboxylated ferulic acid and completely converted 75 mM of this substrate to 4-vinylguaiacol within 2 h at pH 9.0. After the first-stage reaction, cells were removed from the reaction mixture by centrifugation, and the pH of the resulting supernatant was adjusted to 10.5, the optimal pH for Cso2. This solution was subjected to the second-stage reaction. In the second stage, E. coli cells expressing Cso2 efficiently oxidized 4-vinylguaiacol to vanillin. The concentration of vanillin reached 52 mM (7.8 g L(-1)) in 24 h, which is the highest level attained to date for the biotechnological production of vanillin using recombinant cells.

  1. Dynamic changes in gamma-aminobutyric acid and glutamate decarboxylase activity in oats (Avena nuda L.) during steeping and germination.

    Science.gov (United States)

    Xu, Jian Guo; Hu, Qing Ping; Duan, Jiang Lian; Tian, Cheng Rui

    2010-09-01

    Gamma-aminobutyric acid (GABA) is the principal inhibitory neurotransmitter in the central nervous system and provides beneficial effects for human and other animals health. To accumulate GABA, samples from two different naked oat cultivars, Baiyan II and Bayou I, were steeped and germinated in an incubator. The content of GABA and glutamic acid as well as the activity of the glutamate decarboxylase (GAD) in oats during steeping and germination were investigated with an amino acid automatic analyzer. Compared with raw groats, an increase in GABA content of oat groats during steeping and germination was continuously observed for two oat cultivars. The activity of GAD increased greatly at the end of steeping and the second stage of germination for Baiyan II and Bayou I, respectively. Glutamic acid content of treated oat groats was significantly lower than that in raw groats until the later period of germination. GABA was correlated (p<0.01) significantly and positively with the glutamic acid rather than GAD activity in the current study. The results indicates that steeping and germination process under highly controlled conditions can effectively accumulate the GABA in oat groats for Baiyan II and Bayou I, which would greatly facilitate production of nutraceuticals or food ingredients that enable consumers to gain greater access to the health benefits of oats. However, more assays need to be further performed with more oat cultivars.

  2. Differential effect of functional olfactory bulb deafferentation on tyrosine hydroxylase and glutamic acid decarboxylase messenger RNA levels in rodent juxtaglomerular neurons.

    Science.gov (United States)

    Stone, D M; Grillo, M; Margolis, F L; Joh, T H; Baker, H

    1991-09-08

    Expression of the dopaminergic phenotype in olfactory bulb (OB) juxtaglomerular neurons (constituting a population of periglomerular and external tufted cells) is dependent upon functional innervation by peripheral olfactory receptors. Loss of functional input in rodents, by either peripheral deafferentation or deprivation of odorant access, results in a profound decrease in the expression of juxtaglomerular tyrosine hydroxylase (TH). We have examined the effects of such treatments on the expression of the neurotransmitter biosynthetic enzyme glutamic acid decarboxylase (GAD), which is colocalized with TH in the majority of TH-containing juxtaglomerular neurons. Following either chemically induced OB deafferentation in adult mice or unilateral odor deprivation in neonatal rats, steady-state OB GAD messenger RNA levels remained essentially unchanged as assessed by Northern blot analysis 20-40 days after treatment. These results were confirmed by in situ hybridization analysis, which demonstrated a profound loss of juxtaglomerular TH messenger RNA but no accompanying decrease in regionally colocalized GAD message. Since GAD is found in nearly all dopaminergic OB cells, the preservation of juxtaglomerular GAD message implies that olfactory receptor neurons exert a differential transneuronal regulation of TH and GAD gene transcription.

  3. Tomato Glutamate Decarboxylase Genes SlGAD2 and SlGAD3 Play Key Roles in Regulating γ-Aminobutyric Acid Levels in Tomato (Solanum lycopersicum).

    Science.gov (United States)

    Takayama, Mariko; Koike, Satoshi; Kusano, Miyako; Matsukura, Chiaki; Saito, Kazuki; Ariizumi, Tohru; Ezura, Hiroshi

    2015-08-01

    Tomato (Solanum lycopersicum) can accumulate relatively high levels of γ-aminobutyric acid (GABA) during fruit development. However, the molecular mechanism underlying GABA accumulation and its physiological function in tomato fruits remain elusive. We previously identified three tomato genes (SlGAD1, SlGAD2 and SlGAD3) encoding glutamate decarboxylase (GAD), likely the key enzyme for GABA biosynthesis in tomato fruits. In this study, we generated transgenic tomato plants in which each SlGAD was suppressed and those in which all three SlGADs were simultaneously suppressed. A significant decrease in GABA levels, i.e. 50-81% compared with wild-type (WT) levels, was observed in mature green (MG) fruits of the SlGAD2-suppressed lines, while a more drastic reduction (up to tomato fruits. The importance of SlGAD3 expression was also confirmed by generating transgenic tomato plants that over-expressed SlGAD3. The MG and red fruits of the over-expressing transgenic lines contained higher levels of GABA (2.7- to 5.2-fold) than those of the WT. We also determined that strong down-regulation of the SlGADs had little effect on overall plant growth, fruit development or primary fruit metabolism under normal growth conditions.

  4. Buffer-free production of gamma-aminobutyric acid using an engineered glutamate decarboxylase from Escherichia coli.

    Science.gov (United States)

    Kang, Taek Jin; Ho, Ngoc Anh Thu; Pack, Seung Pil

    2013-08-15

    Escherichia coli glutamate decarboxylase (GAD) converts glutamate into γ-aminobutyric acid (GABA) through decarboxylation using proton as a co-substrate. Since GAD is active only at acidic conditions even though pH increases as the reaction proceeds, the conventional practice of using this enzyme involved the use of relatively high concentration of buffers, which might complicate the downstream purification steps. Here we show by simulation and experiments that the free acid substrate, glutamic acid, rather than its monosodium salt can act as a substrate and buffer at the same time. This yielded the buffer- and salt-free synthesis of GABA conveniently in a batch mode. Furthermore, we engineered GAD to hyper active ones by extending or reducing the length of the enzyme by just one residue at its C-terminus. Through the buffer-free reaction with engineered GAD, we could synthesize 1M GABA in 3h, which can be translated into a space-time yield of 34.3g/L/h.

  5. Cloning and sequencing of pyruvate decarboxylase (PDC) genes from bacteria and uses therefor

    Science.gov (United States)

    Maupin-Furlow, Julie A [Gainesville, FL; Talarico, Lee Ann [Gainesville, FL; Raj, Krishnan Chandra [Tamil Nadu, IN; Ingram, Lonnie O [Gainesville, FL

    2008-02-05

    The invention provides isolated nucleic acids molecules which encode pyruvate decarboxylase enzymes having improved decarboxylase activity, substrate affinity, thermostability, and activity at different pH. The nucleic acids of the invention also have a codon usage which allows for high expression in a variety of host cells. Accordingly, the invention provides recombinant expression vectors containing such nucleic acid molecules, recombinant host cells comprising the expression vectors, host cells further comprising other ethanologenic enzymes, and methods for producing useful substances, e.g., acetaldehyde and ethanol, using such host cells.

  6. Effects of S-adenosylmethionine decarboxylase, polyamines, amino acids, and weak bases (amines and ammonia) on development and ribosomal RNA synthesis in Xenopus embryos.

    Science.gov (United States)

    Shiokawa, Koichiro; Aso, Mai; Kondo, Takeshi; Takai, Jun-Ichi; Yoshida, Junki; Mishina, Takamichi; Fuchimukai, Kota; Ogasawara, Tsukasa; Kariya, Taro; Tashiro, Kosuke; Igarashi, Kazuei

    2010-02-01

    We have been studying control mechanisms of gene expression in early embryogenesis in a South African clawed toad Xenopus laevis, especially during the period of midblastula transition (MBT), or the transition from the phase of active cell division (cleavage stage) to the phase of extensive morphogenesis (post-blastular stages). We first found that ribosomal RNA synthesis is initiated shortly after MBT in Xenopus embryos and those weak bases, such as amines and ammonium ion, selectively inhibit the initiation and subsequent activation of rRNA synthesis. We then found that rapidly labeled heterogeneous mRNA-like RNA is synthesized in embryos at pre-MBT stage. We then performed cloning and expression studies of several genes, such as those for activin receptors, follistatin and aldolases, and then reached the studies of S-adenosylmethionine decarboxylase (SAMDC), a key enzyme in polyamine metabolism. Here, we cloned a Xenopus SAMDC cDNA and performed experiments to overexpress the in vitro-synthesized SAMDC mRNA in Xenopus early embryos, and found that the maternally preset program of apoptosis occurs in cleavage stage embryos, which is executed when embryos reach the stage of MBT. In the present article, we first summarize results on SAMDC and the maternal program of apoptosis, and then describe our studies on small-molecular-weight substances like polyamines, amino acids, and amines in Xenopus embryos. Finally, we summarize our studies on weak bases, especially on ammonium ion, as the specific inhibitor of ribosomal RNA synthesis in Xenopus embryonic cells.

  7. Induction of aromatic L-amino acid decarboxylase mRNA by interleukin-1 beta and prostaglandin E2 in PC12 cells.

    Science.gov (United States)

    Li, X M; Juorio, A V; Boulton, A A

    1994-05-01

    Aromatic 1-amino acid decarboxylase (AADC) is involved in the synthesis of the putative neurotransmitters dopamine (DA), norepinephrine (NA) and 5-hydroxytryptamine (5-HT). We report here that the gene expression of AADC can be regulated by interleukin (IL) 1-beta and prostaglandin (PG) E2 in PC12 cells. The cells were treated with different doses of IL 1-beta and PGE2 for 3 days. Slot blot hybridization was performed to detect AADC mRNA and Western immunoblot to detect AADC protein. The cDNA probe for rat AADC was generated by the PCR method. IL 1-beta and PGE2 produced a dose- and time-dependent up-regulation in AADC mRNA levels (up to 200% of the control values) which was followed by a stable increase in AADC protein. The data further support the suggestion that AADC is a regulated enzyme and that the regulation occurs at the level of gene expression. Because IL-1 is synthesized, and acts locally, within the brain to influence neuronal and glial functions, it has been proposed to be a mediator with both beneficial and detrimental responses to inflammation and injury. The regulation of AADC by IL-1 may indicate a possible involvement for AADC in neuronal injury and recovery. Since IL-1 promotes PGE2 formation, its effects may be occurring by increasing level of PGE2.

  8. Over-expression of mouse ornithine decarboxylase gene under the control of fruit-specific promoter enhances fruit quality in tomato.

    Science.gov (United States)

    Pandey, Roopali; Gupta, Aarti; Chowdhary, Anuj; Pal, Ram Krishna; Rajam, Manchikatla Venkat

    2015-02-01

    Diamine putrescine (Put) and polyamines; spermidine (Spd) and spermine (Spm) are essential component of every cell because of their involvement in the regulation of cell division, growth and development. The aim of this study is to enhance the levels of Put during fruit development and see its implications in ripening and quality of tomato fruits. Transgenic tomato plants over-expressing mouse ornithine decarboxylase gene under the control of fruit-specific promoter (2A11) were developed. Transgenic fruits exhibited enhanced levels of Put, Spd and Spm, with a concomitant reduction in ethylene levels, rate of respiration and physiological loss of water. Consequently such fruits displayed significant delay of on-vine ripening and prolonged shelf life over untransformed fruits. The activation of Put biosynthetic pathway at the onset of ripening in transgenic fruits is also consistent with the improvement of qualitative traits such as total soluble solids, titratable acids and total sugars. Such changes were associated with alteration in expression pattern of ripening specific genes. Transgenic fruits were also fortified with important nutraceuticals like lycopene, ascorbate and antioxidants. Therefore, these transgenic tomatoes would be useful for the improvement of tomato cultivars through breeding approaches.

  9. Role of ornithine decarboxylase in regulation of estrogen receptor alpha expression and growth in human breast cancer cells

    Science.gov (United States)

    Zhu, Qingsong; Jin, Lihua; Casero, Robert A.

    2013-01-01

    Our previous studies demonstrated that specific polyamine analogues, oligoamines, down-regulated the activity of a key polyamine biosynthesis enzyme, ornithine decarboxylase (ODC), and suppressed expression of estrogen receptor alpha (ERα) in human breast cancer cells. However, the mechanism underlying the potential regulation of ERα expression by polyamine metabolism has not been explored. Here, we demonstrated that RNAi-mediated knockdown of ODC (ODC KD) down-regulated the polyamine pool, and hindered growth in ERα-positive MCF7 and T47D and ERα-negative MDA-MB-231 breast cancer cells. ODC KD significantly induced the expression and activity of the key polyamine catabolism enzymes, spermine oxidase (SMO) and spermidine/spermine N1-acetyltransferase (SSAT). However, ODC KD-induced growth inhibition could not be reversed by exogenous spermidine or overexpression of antizyme inhibitor (AZI), suggesting that regulation of ODC on cell proliferation may involve the signaling pathways independent of polyamine metabolism. In MCF7 and T47D cells, ODC KD, but not DFMO treatment, diminished the mRNA and protein expression of ERα. Overexpression of antizyme (AZ), an ODC inhibitory protein, suppressed ERα expression, suggesting that ODC plays an important role in regulation of ERα expression. Decrease of ERα expression by ODC siRNA altered the mRNA expression of a subset of ERα response genes. Our previous analysis showed that oligoamines disrupt the binding of Sp1 family members to an ERα minimal promoter element containing GC/CA-rich boxes. By using DNA affinity precipitation and mass spectrometry analysis, we identified ZBTB7A, MeCP2, PARP-1, AP2, and MAZ as co-factors of Sp1 family members that are associated with the ERα minimal promoter element. Taken together, these data provide insight into a novel antiestrogenic mechanism for polyamine biosynthesis enzymes in breast cancer. PMID:22976807

  10. Role of dopamine in the plasticity of glutamic acid decarboxylase messenger RNA in the rat frontal cortex and the nucleus accumbens.

    Science.gov (United States)

    Rétaux, S; Trovero, F; Besson, M J

    1994-12-01

    The modulatory role of dopamine (DA) on the expression of mRNA encoding the large isoform of glutamic acid decarboxylase (GAD67), the biosynthesis enzyme of gamma aminobutyric acid (GABA), was examined in GABA neurons of two structures innervated by DA neurons originating from the ventral tegmental area (VTA): the medial frontal cortex (MFC) and the nucleus accumbens (NAcc). A bilateral electrolytic lesion of VTA was performed in rats to produce a DA denervation of both the MFC and NAcc. The efficacy of VTA lesions was verified by measurement of locomotor activity and by immunohistochemical detection of tyrosine hydroxylase in the mesencephalon. GAD67 mRNA was detected by in situ hybridization histochemistry using a 35S-labelled cDNA probe. Densitometric analysis of GAD67 mRNA hybridization signals revealed in VTA-lesioned rats a significant decrease (-24%) in GAD67 mRNA levels in the prelimbic area of the MFC and no significant effect in the anterior cingulate area or the frontoparietal cortex. Single cell analyses by computer-assisted grain counting showed that the decrease in GAD67 mRNA levels in prelimbic MFC was due to a change in GAD67 mRNA expression in a subpopulation of GABA interneurons located in the deep cortical layers (V-VI). By contrast, in the NAcc of VTA-lesioned rats, GAD67 mRNA levels were significantly increased in the anterior part and in the core but were unchanged in the shell part. These results suggest that in two target structures of VTA DA neurons, GAD67 mRNA expression is, in normal conditions, under a tonic stimulatory and a tonic inhibitory DA control in the MFC and the NAcc respectively. A schematic diagram is proposed for functional interactions between these structures.

  11. Spinal Cord Hemisection Facilitates Aromatic L-Amino Acid Decarboxylase Cells to Produce Serotonin in the Subchronic but Not the Chronic Phase

    Directory of Open Access Journals (Sweden)

    Bushra Azam

    2015-01-01

    Full Text Available Neuromodulators, such as serotonin (5-hydroxytryptamine, 5-HT and noradrenalin, play an essential role in regulating the motor and sensory functions in the spinal cord. We have previously shown that in the rat spinal cord the activity of aromatic L-amino acid decarboxylase (AADC cells to produce 5-HT from its precursor (5-hydroxytryptophan, 5-HTP is dramatically increased following complete spinal cord transection. In this study, we investigated whether a partial loss of 5-HT innervation could similarly increase AADC activity. Adult rats with spinal cord hemisected at thoracic level (T11/T12 were used with a postoperation interval at 5 days or 60 days. Using immunohistochemistry, first, we observed a significant reduction in the density of 5-HT-immunoreactive fibers in the spinal cord below the lesion on the injured side for both groups. Second, we found that the AADC cells were similarly expressed on both injured and uninjured sides in both groups. Third, increased production of 5-HT in AADC cells following 5-HTP was seen in 5-day but not in 60-day postinjury group. These results suggest that plastic changes of the 5-HT system might happen primarily in the subchronic phase and for longer period its function could be compensated by plastic changes of other intrinsic and/or supraspinal modulation systems.

  12. Production of itaconate by whole-cell bioconversion of citrate mediated by expression of multiple cis-aconitate decarboxylase (cadA) genes in Escherichia coli

    Science.gov (United States)

    Kim, Junyoung; Seo, Hyung-Min; Bhatia, Shashi Kant; Song, Hun-Seok; Kim, Jung-Ho; Jeon, Jong-Min; Choi, Kwon-Young; Kim, Wooseong; Yoon, Jeong-Jun; Kim, Yun-Gon; Yang, Yung-Hun

    2017-01-01

    Itaconate, a C5 unsaturated dicarboxylic acid, is an important chemical building block that is used in manufacturing high-value products, such as latex and superabsorbent polymers. Itaconate is produced by fermentation of sugars by the filamentous fungus Aspergillus terreus. However, fermentation by A. terreus involves a long fermentation period and the formation of various byproducts, resulting in high production costs. E. coli has been developed as an alternative for producing itaconate. However, fermentation of glucose gives low conversion yields and low productivity. Here, we report the whole-cell bioconversion of citrate to itaconate with enhanced aconitase and cis-aconitate decarboxylase activities by controlling the expression of multiple cadA genes. In addition, this bioconversion system does not require the use of buffers, which reduces the production cost and the byproducts released during purification. Using this whole-cell bioconversion system, we were able to catalyze the conversion of 319.8 mM of itaconate (41.6 g/L) from 500 mM citrate without any buffer system or additional cofactors, with 64.0% conversion in 19 h and a productivity of 2.19 g/L/h. Our bioconversion system suggests very high productivity for itaconate production. PMID:28051098

  13. The selective conversion of glutamic acid in amino acid mixtures using glutamate decarboxylase--a means of separating amino acids for synthesizing biobased chemicals.

    Science.gov (United States)

    Teng, Yinglai; Scott, Elinor L; Sanders, Johan P M

    2014-01-01

    Amino acids (AAs) derived from hydrolysis of protein rest streams are interesting feedstocks for the chemical industry due to their functionality. However, separation of AAs is required before they can be used for further applications. Electrodialysis may be applied to separate AAs, but its efficiency is limited when separating AAs with similar isoelectric points. To aid the separation, specific conversion of an AA to a useful product with different charge behavior to the remaining compounds is desired. Here the separation of L-aspartic acid (Asp) and L-glutamic acid (Glu) was studied. L-Glutamate α-decarboxylase (GAD, Type I, EC 4.1.1.15) was applied to specifically convert Glu into γ-aminobutyric acid (GABA). GABA has a different charge behavior from Asp therefore allowing a potential separation by electrodialysis. Competitive inhibition and reduced operational stability caused by Asp could be eliminated by maintaining a sufficiently high concentration of Glu. Immobilization of GAD does not reduce the enzyme's initial activity. However, the operational stability was slightly reduced. An initial study on the reaction operating in a continuous mode was performed using a column reactor packed with immobilized GAD. As the reaction mixture was only passed once through the reactor, the conversion of Glu was lower than expected. To complete the conversion of Glu, the stream containing Asp and unreacted Glu might be recirculated back to the reactor after GABA has been removed. Overall, the reaction by GAD is specific to Glu and can be applied to aid the electrodialysis separation of Asp and Glu.

  14. Anti-Glutamic Acid Decarboxylase Antibody-Associated Ataxia as an Extrahepatic Autoimmune Manifestation of Hepatitis C Infection: A Case Report

    Directory of Open Access Journals (Sweden)

    Amer Awad

    2011-01-01

    Full Text Available Extrahepatic immunological manifestations of hepatitis C virus (HCV are well described. In addition, antiglutamic acid decarboxylase (GAD antibody-associated cerebellar ataxia is well-established entity. However, there have been no reports in the literature of anti-GAD antibody-associated ataxia as an extrahepatic manifestation of HCV infection. We report the case of a young woman with chronic hepatitis C virus and multiple extrahepatic autoimmune diseases including Sjögren syndrome and pernicious anemia who presented with subacute midline cerebellar syndrome and was found to have positive antiglutamic acid decarboxylase (GAD antibody in the serum and cerebrospinal fluid. An extensive diagnostic workup to rule out neoplastic growths was negative, suggesting the diagnosis of nonparaneoplastic antiglutamic acid decarboxylase antibody-associated cerebellar ataxia as an additional extrahepatic manifestation of hepatitis C virus infection. The patient failed to respond to high-dose steroids and intravenous immunoglobulin. Treatment with the monoclonal antibody rituximab stabilized the disease. We postulate that anti-GAD associated ataxia could be an extrahepatic manifestation of HCV infection.

  15. Anti-glutamic Acid decarboxylase antibody-associated ataxia as an extrahepatic autoimmune manifestation of hepatitis C infection: a case report.

    Science.gov (United States)

    Awad, Amer; Stüve, Olaf; Mayo, Marlyn; Alkawadri, Rafeed; Estephan, Bachir

    2011-01-01

    Extrahepatic immunological manifestations of hepatitis C virus (HCV) are well described. In addition, antiglutamic acid decarboxylase (GAD) antibody-associated cerebellar ataxia is well-established entity. However, there have been no reports in the literature of anti-GAD antibody-associated ataxia as an extrahepatic manifestation of HCV infection. We report the case of a young woman with chronic hepatitis C virus and multiple extrahepatic autoimmune diseases including Sjögren syndrome and pernicious anemia who presented with subacute midline cerebellar syndrome and was found to have positive antiglutamic acid decarboxylase (GAD) antibody in the serum and cerebrospinal fluid. An extensive diagnostic workup to rule out neoplastic growths was negative, suggesting the diagnosis of nonparaneoplastic antiglutamic acid decarboxylase antibody-associated cerebellar ataxia as an additional extrahepatic manifestation of hepatitis C virus infection. The patient failed to respond to high-dose steroids and intravenous immunoglobulin. Treatment with the monoclonal antibody rituximab stabilized the disease. We postulate that anti-GAD associated ataxia could be an extrahepatic manifestation of HCV infection.

  16. Sexually dimorphic expression of glutamate decarboxylase mRNA in the hypothalamus of the deep sea armed grenadier, Coryphaenoides (Nematonurus) armatus.

    Science.gov (United States)

    Trudeau, V L; Bosma, P T; Collins, M; Priede, I G; Docherty, K

    2000-11-01

    Glutamate decarboxylase (GAD), is a key enzyme in the central nervous system (CNS) that synthesizes the inhibitory neurotransmitter gamma-aminobutyric acid (GABA) from glutamate. Our previous phylogenetic studies on the evolution of this enzyme indicates that there are at least two distinct forms: GAD65 and GAD67. They are the products of separate genes and probably derive from a common ancestral GAD gene following gene duplication prior to the emergence of the teleosts more than 200 Myr ago. Furthermore, a third GAD-like molecule, GAD3, discovered in the armed grenadier, Coryphaenoides (Nematonurus) armatus, is equally divergent from both GAD65 and GAD67. Specimens of C. (N.) armatus were collected by trawl at a depth of 4,000 m in the Porcupine Seabight (Northeastern Atlantic), and brains dissected and frozen for RNA extraction. All three GAD forms are found in the cerebellum, telencephalon and hypothalamus. Semiquantitative PCR analysis showed that males and females have similar levels of expression of GAD67 and GAD3 in the tissues studied. Independent of the sex examined, the levels of expression of GAD65 and GAD67 in the cerebellum were approximately half that in the telencephalon. GAD3 levels were approximately 30% higher in the cerebellum than in either the telencephalon or hypothalamus. In contrast to GAD67 and GAD3, hypothalamic expression of GAD65 mRNA is 1.8 times higher (p < 0.05) in males than in females. These data indicate that the expression of GAD65, a key enzyme for the synthesis of GABA is sexually dimorphic in females and males of C. (N.) armatus.

  17. Pyridoxine Supplementation Improves the Activity of Recombinant Glutamate Decarboxylase and the Enzymatic Production of Gama-Aminobutyric Acid.

    Directory of Open Access Journals (Sweden)

    Yan Huang

    Full Text Available Glutamate decarboxylase (GAD catalyzes the irreversible decarboxylation of L-glutamate to the valuable food supplement γ-aminobutyric acid (GABA. In this study, GAD from Escherichia coli K12, a pyridoxal phosphate (PLP-dependent enzyme, was overexpressed in E. coli. The GAD produced in media supplemented with 0.05 mM soluble vitamin B6 analog pyridoxine hydrochloride (GAD-V activity was 154.8 U mL-1, 1.8-fold higher than that of GAD obtained without supplementation (GAD-C. Purified GAD-V exhibited increased activity (193.4 U mg-1, 1.5-fold higher than that of GAD-C, superior thermostability (2.8-fold greater than that of GAD-C, and higher kcat/Km (1.6-fold higher than that of GAD-C. Under optimal conditions in reactions mixtures lacking added PLP, crude GAD-V converted 500 g L-1 monosodium glutamate (MSG to GABA with a yield of 100%, and 750 g L-1 MSG with a yield of 88.7%. These results establish the utility of pyridoxine supplementation and lay the foundation for large-scale enzymatic production of GABA.

  18. Distribution of messenger RNAs encoding the enzymes glutaminase, aspartate aminotransferase and glutamic acid decarboxylase in rat brain.

    Science.gov (United States)

    Najlerahim, A; Harrison, P J; Barton, A J; Heffernan, J; Pearson, R C

    1990-05-01

    In situ hybridization histochemistry (ISHH) using synthetic oligonucleotide probes has been used to identify cells containing the mRNAs coding for glutaminase (GluT), aspartate aminotransferase (AspT) and glutamic acid decarboxylase (GAD). The distribution of GAD mRNA confirms previous descriptions and matches the distribution of GAD detected using specific antibodies. AspT mRNA is widely distributed in the brain, but is present at high levels in GABAergic neuronal populations, some that may be glutamatergic, and in a subset of neurons which do not contain significant levels of either GAD or GluT mRNA. Particularly prominent are the neurons of the magnocellular division of the red nucleus, the large cells in the deep cerebellar nuclei and the vestibular nuclei and neurons of the lateral superior olivary nucleus. GluT mRNA does not appear to be present at high levels in all GAD-containing neurons, but is seen prominently in many neuronal populations that may use glutamate as a neurotransmitter, such as neocortical and hippocampal pyramidal cells, the granule cells of the cerebellum and neurons of the dentate gyrus of the hippocampus. The heaviest labelling of GluT mRNA is seen in the lateral reticular nucleus of the medulla. ISHH using probes directed against the mRNAs encoding these enzymes may be an important technique for identifying glutamate and aspartate using neuronal populations and for examining their regulation in a variety of experimental and pathological circumstances.

  19. Expression of arginine decarboxylase is induced during early fruit development and in young tissues of Pisum sativum (L.).

    Science.gov (United States)

    Pérez-Amador, M A; Carbonell, J; Granell, A

    1995-09-01

    A cDNA coding for arginine decarboxylase (ADC, EC 4.1.1.19) has been isolated from a cDNA library of parthenocarpic young fruits of Pisum sativum (L.). The deduced aminoacid sequence is 74%, 46% and 35% identical to ADCs from tomato, oat and Escherichia coli, respectively. When the pea ADC cDNA was put under the control of the galactose inducible yeast promoter CYC1-GAL10 and introduced into Saccharomyces cerevisiae, it conferred galactose-regulated expression of the ADC activity. The ADC activity expressed in S. cerevisiae was inhibited 99% by alpha-DL-difluoromethylarginine (DFMA), a specific inhibitor of ADC activity. No activity was detected in the untransformed S. cerevisiae, nor when it was transformed with an antisense ADC construct. This provides direct evidence that the ADC cDNA from pea encoded a functional, specific ADC activity and that S. cerevisiae is able to process correctly the protein. In the pea plant, gene expression of the ADC is high in young developing tissues like shoot tips, young leaflets and flower buds. Fully expanded leaflets and roots have much lower, but still detectable, levels of the ADC transcript. In the ovary and fruit, they are developmentally regulated, showing high levels of expression during the early stages of fruit growth, which in pea is mainly due to cell expansion. The observed changes in the steady-state levels of ADC mRNA alone, however, cannot account for the differences in ADC activity suggesting that other regulatory mechanisms must be acting.

  20. MDMA decreases glutamic acid decarboxylase (GAD) 67-immunoreactive neurons in the hippocampus and increases seizure susceptibility: Role for glutamate.

    Science.gov (United States)

    Huff, Courtney L; Morano, Rachel L; Herman, James P; Yamamoto, Bryan K; Gudelsky, Gary A

    2016-12-01

    3,4-Methylenedioxy-methamphetamine (MDMA) is a unique psychostimulant that continues to be a popular drug of abuse. It has been well documented that MDMA reduces markers of 5-HT axon terminals in rodents, as well as humans. A loss of parvalbumin-immunoreactive (IR) interneurons in the hippocampus following MDMA treatment has only been documented recently. In the present study, we tested the hypothesis that MDMA reduces glutamic acid decarboxylase (GAD) 67-IR, another biochemical marker of GABA neurons, in the hippocampus and that this reduction in GAD67-IR neurons and an accompanying increase in seizure susceptibility involve glutamate receptor activation. Repeated exposure to MDMA (3×10mg/kg, ip) resulted in a reduction of 37-58% of GAD67-IR cells in the dentate gyrus (DG), CA1, and CA3 regions, as well as an increased susceptibility to kainic acid-induced seizures, both of which persisted for at least 30days following MDMA treatment. Administration of the NMDA antagonist MK-801 or the glutamate transporter type 1 (GLT-1) inducer ceftriaxone prevented both the MDMA-induced loss of GAD67-IR neurons and the increased vulnerability to kainic acid-induced seizures. The MDMA-induced increase in the extracellular concentration of glutamate in the hippocampus was significantly diminished in rats treated with ceftriaxone, thereby implicating a glutamatergic mechanism in the neuroprotective effects of ceftriaxone. In summary, the present findings support a role for increased extracellular glutamate and NMDA receptor activation in the MDMA-induced loss of hippocampal GAD67-IR neurons and the subsequent increased susceptibility to evoked seizures.

  1. Regulation of human ornithine decarboxylase expression following prolonged quiescence: role for the c-Myc/Max protein complex.

    Science.gov (United States)

    Peña, A; Wu, S; Hickok, N J; Soprano, D R; Soprano, K J

    1995-02-01

    WI-38 cells can remain quiescent for long periods of time and still be induced to reenter the cell cycle by the addition of fresh serum. However, the longer these cells remain growth arrested, the more time they require to enter S phase. This prolongation of the prereplicative phase has been localized to a point early in G1, after the induction of "immediate early" G1 genes such as c-fos and c-jun but before maximal expression of "early" G1 genes such as ornithine decarboxylase (ODC). Understanding the molecular basis for ODC mRNA induction can therefore provide information about the molecular events which regulate the progression of cells out of long-term quiescence into G1 and subsequently into DNA synthesis. Studies utilizing electrophoretic mobility shift assays (EMSA) of nuclear extracts from short- and long-term quiescent WI-38 cells identified a region of the human ODC promoter at -491 bp to -474 bp which exhibited a protein binding pattern that correlated with the temporal pattern of ODC mRNA expression. The presence of a CACGTG element within this fragment, studies with antibodies against c-Myc and Max, the use of purified recombinant c-Myc protein in the mobility shift assay, and antisense studies suggest that these proteins can specifically bind this portion of the human ODC promoter in a manner consistent with growth-associated modulation of the expression of ODC and other early G1 genes following prolonged quiescence. These studies suggest a role for the c-Myc/Max protein complex in regulating events involved in the progression of cells out of long-term quiescence into G1 and subsequently into S.

  2. The expanding spectrum of pediatric anti-glutamic acid decarboxylase antibody mediated CNS disease - a chance association?

    Institute of Scientific and Technical Information of China (English)

    Deepak Menon; Ramshekhar N Menon; Hardeep Kumar; Ashalatha Radhakrishnan; Sudheeran Kannoth; Muralidharan Nair; Sanjeev Thomas

    2016-01-01

    Central nervous system autoimmunity in the pediatric age group represents an evolving constellation of various syndromes distinct from the adult age group. One of the rarely described pathogenic auto-antibodies (ab) is the one directed against glutamic acid decarboxylase (GAD). While its pathogenic role is controversial, literature concerning adult patients abounds with heterogeneous presentations with epilepsy often as part of limbic encephalitis or chronic temporal lobe epilepsy and cerebellar ataxia accompanying endocrinopathies or paraneoplastic disorders. Diagnosis is often delayed until late adulthood. The authors report hitherto under-reported syndromes in the pediatric age group. The ifrst case was a 3-year-old boy with sub-acute myoclonus-ataxia following a lfu-like illness akin to para-infectious cerebellitis. The second case was a 7-year-old girl with long-standing chronic extratemporal partial epilepsy and electrical status epilepticus in sleep (ESES) with right hemiparesis and developmental delay. Investigations revealed two-four fold elevations in titres of GAD-65-ab. The absence of systemic diseases like diabetes and the dramatic clinical response to steroids as well as intravenous immunoglobulin in both the cases argued for GAD-ab mediated neuronal injury rather than a chance association. The concern exists regarding other potentially co-existent auto-ab to gamma-amino butyric acid and glycine receptors, and demonstration of intrathecal synthesis of GAD-ab would be ideal. This entity should be contemplated in children presenting with acute/sub-acute onset episodic or progressive ataxia or refractory cryptogenic focal epilepsy syndromes, epileptic encephalopathy such as ESES and worsening neurological deifcits. These children ought to be maintained on regular follow-up for monitoring evolution of other autoimmune disorders in adult life.

  3. Glutamic acid decarboxylase 65: a link between GABAergic synaptic plasticity in the lateral amygdala and conditioned fear generalization.

    Science.gov (United States)

    Lange, Maren D; Jüngling, Kay; Paulukat, Linda; Vieler, Marc; Gaburro, Stefano; Sosulina, Ludmila; Blaesse, Peter; Sreepathi, Hari K; Ferraguti, Francesco; Pape, Hans-Christian

    2014-08-01

    An imbalance of the gamma-aminobutyric acid (GABA) system is considered a major neurobiological pathomechanism of anxiety, and the amygdala is a key brain region involved. Reduced GABA levels have been found in anxiety patients, and genetic variations of glutamic acid decarboxylase (GAD), the rate-limiting enzyme of GABA synthesis, have been associated with anxiety phenotypes in both humans and mice. These findings prompted us to hypothesize that a deficiency of GAD65, the GAD isoform controlling the availability of GABA as a transmitter, affects synaptic transmission and plasticity in the lateral amygdala (LA), and thereby interferes with fear responsiveness. Results indicate that genetically determined GAD65 deficiency in mice is associated with (1) increased synaptic length and release at GABAergic connections, (2) impaired efficacy of GABAergic synaptic transmission and plasticity, and (3) reduced spillover of GABA to presynaptic GABAB receptors, resulting in a loss of the associative nature of long-term synaptic plasticity at cortical inputs to LA principal neurons. (4) In addition, training with high shock intensities in wild-type mice mimicked the phenotype of GAD65 deficiency at both the behavioral and synaptic level, indicated by generalization of conditioned fear and a loss of the associative nature of synaptic plasticity in the LA. In conclusion, GAD65 is required for efficient GABAergic synaptic transmission and plasticity, and for maintaining extracellular GABA at a level needed for associative plasticity at cortical inputs in the LA, which, if disturbed, results in an impairment of the cue specificity of conditioned fear responses typifying anxiety disorders.

  4. Cloning and expression of ornithine decarboxylase gene from human colorectal carcinoma

    Institute of Scientific and Technical Information of China (English)

    Hai-Yan Hu; Xiao-Ming Wang; Wei Wang; Xian-Xi Liu; Chun-Ying Jiang; Yan Zhang; Ji-Feng Bian; Yi Lu; Zhao Geng; Shi-Lian Liu; Chuan-Hua Liu

    2003-01-01

    AIM: To construct and express ODC recombinant gene for further exploring its potential use in early diagnosis of colorectal carcinoma.METHODS: Total RNA was extracted from colon cancer tissues and amplified by reverse-transcription PCR with two primers, which span the whole coding region of ODC. The synthesized ODC cDNA was cloned into vector pQE-30 at restriction sites BamH I and Sal I which constituted recombinant expression plasmid pQE30-ODC. The sequence of inserted fragment was confirmed by DNA sequencing,the fusion protein including 6His-tag was facilitated for purification by Ni-NTA chromatographic column.RESULTS: ODC expression vector was constructed and confirmed with restriction enzyme digestion and subsequent DNA sequencing. The DNA sequence matching on NCBI Blast showed 99 % affinity. The vector was transformed into E.coli M15 and expressed. The expressed ODC protein was verified with Western blotting.CONCLUSION: The ODC prokaryote expression vector is constructed and thus greatly facilitates to study the role of ODC in colorectal carcinoma.

  5. Gene expression of ornithine decarboxylase, cyclooxygenase-2, and gastrin in atrophic gastric mucosa infected with Helicobacter pylori before and after eradication therapy.

    Science.gov (United States)

    Konturek, Peter C; Rembiasz, Kazimierz; Konturek, Stanislaw J; Stachura, Jerzy; Bielanski, Wladyslaw; Galuschka, K; Karcz, Danuta; Hahn, Eckhart G

    2003-01-01

    H. pylori (Hp) -induced atrophic gastritis is a well-known risk factor for the development of gastric cancer. Whether Hp eradication can prevent or retard the progress of atrophy and metaplasia has been the topic of numerous studies but the subject remains controversial. Recently, the increased expression of ornithine decarboxylase (ODC), gastrin and cyclooxygenase (COX)-2 has been shown to be increased in premalignant lesions in gastric mucosa and to play an essential role in the malignant transformation. The aim of the study is to assess the effect of eradication therapy on atrophic gastritis and analyze the gene expression for ODC, COX-2 and gastrin in gastric mucosa after succesful eradication in patients with atrophic gastritis. Twenty patients with chronic atrophic gastritis including both corpus and antrum of the stomach were included in this study. Four antral mucosal biopsy specimens were obtained from antrum and four from corpus. The histopathologic evaluation of gastritis was based on Sydney classification of gastritis. All patients were Hp positive based on the [13C] urea breath test (UBT) and the presence of anti-Hp IgG and anti-CagA-antibodies detected by ELISA. The patients were then eradicated with triple therapy consiting of omeprazol (2 x 20 mg), amoxycillin (2 x 1 g) and clarithromycin (2 x 500 mg) for seven days and vitamin C 1 g/day for three months. In gastric mucosal samples obtained from the antrum and corpus before and after eradication, the mRNA expression for ODC, COX-2, and gastrin was assessed by reverse-transcription polymerase chain reaction (RT-PCR). In all patients the gastric secretory analysis was performed by measuring gastric acid output and serum gastrin levels. After triple therapy the successful eradication assessed by UBT was observed in 95% of patients. In 45% of patients the infection with CagA-positive Hp strain was observed. Three months after eradication a significant reduction in the gastric activity (neutrophilic

  6. Substrate Specificity of Thiamine Pyrophosphate-Dependent 2-Oxo-Acid Decarboxylases in Saccharomyces cerevisiae

    NARCIS (Netherlands)

    Romagnoli, G.; Luttik, M.A.H.; Kötter, P.; Pronk, J.T.; Daran, J.M.

    2012-01-01

    Fusel alcohols are precursors and contributors to flavor and aroma compounds in fermented beverages, and some are under investigation as biofuels. The decarboxylation of 2-oxo acids is a key step in the Ehrlich pathway for fusel alcohol production. In Saccharomyces cerevisiae, five genes share seque

  7. Enhancement of the catalytic activity of ferulic acid decarboxylase from Enterobacter sp. Px6-4 through random and site-directed mutagenesis.

    Science.gov (United States)

    Lee, Hyunji; Park, Jiyoung; Jung, Chaewon; Han, Dongfei; Seo, Jiyoung; Ahn, Joong-Hoon; Chong, Youhoon; Hur, Hor-Gil

    2015-11-01

    The enzyme ferulic acid decarboxylase (FADase) from Enterobacter sp. Px6-4 catalyzes the decarboxylation reaction of lignin monomers and phenolic compounds such as p-coumaric acid, caffeic acid, and ferulic acid into their corresponding 4-vinyl derivatives, that is, 4-vinylphenol, 4-vinylcatechol, and 4-vinylguaiacol, respectively. Among various ferulic acid decarboxylase enzymes, we chose the FADase from Enterobacter sp. Px6-4, whose crystal structure is known, and produced mutants to enhance its catalytic activity by random and site-directed mutagenesis. After three rounds of sequential mutations, FADase(F95L/D112N/V151I) showed approximately 34-fold higher catalytic activity than wild-type for the production of 4-vinylguaiacol from ferulic acid. Docking analyses suggested that the increased activity of FADase(F95L/D112N/V151I) could be due to formation of compact active site compared with that of the wild-type FADase. Considering the amount of phenolic compounds such as lignin monomers in the biomass components, successfully bioengineered FADase(F95L/D112N/V151I) from Enterobacter sp. Px6-4 could provide an ecofriendly biocatalytic tool for producing diverse styrene derivatives from biomass.

  8. Spinal cord injury enables aromatic l-amino acid decarboxylase cells to synthesize monoamines

    DEFF Research Database (Denmark)

    Wienecke, Jacob; Ren, Li-Qun; Hultborn, Hans

    2014-01-01

    a loss of inhibition by descending 5-HT neurons and to be mediated by 5-HT1B receptors expressed by AADC cells. These findings indicate that AADC cells are a potential source of 5-HT at spinal levels below an SCI. The production of 5-HT by AADC cells, together with an upregulation of 5-HT2 receptors...

  9. Functional analysis and transcriptional regulation of two orthologs of ARO10, encoding broad-substrate-specificity 2-oxo-acid decarboxylases, in the brewing yeast Saccharomyces pastorianus CBS1483.

    Science.gov (United States)

    Bolat, Irina; Romagnoli, Gabriele; Zhu, Feibai; Pronk, Jack T; Daran, Jean-Marc

    2013-09-01

    The hybrid genomes of Saccharomyces pastorianus consist of subgenomes similar to those of S. cerevisiae and S. eubayanus, and impact of the genome structure on flavour production and its regulation is poorly understood. This study focuses on ARO10, a 2-oxo-acid decarboxylase involved in production of higher alcohols. In S. pastorianus CBS1483, four ARO10 copies were identified, three resembled S. cerevisiae ARO10 and one S. eubayanus ARO10. Substrate specificities of lager strain (Lg)ScAro10 and LgSeubAro10 were compared by individually expressing them in a pdc1Δ-pdc5Δ-pdc6Δ-aro10Δ-thi3Δ S. cerevisiae strain. Both isoenzymes catalysed decarboxylation of the 2-oxo-acids derived from branched-chain, sulphur-containing amino acids and preferably phenylpyruvate. Expression of both alleles was induced by phenylalanine, however in contrast to the S. cerevisiae strain, the two genes were not induced by leucine. Additionally, LgSeubARO10 showed higher basal expression levels during growth with ammonia. ARO80, which encodes ARO10 transcriptional activator, is located on CHRIV and counts three Sc-like and one Seub-like copies. Deletion of LgSeubARO80 did not affect LgSeubARO10 phenylalanine induction, revealing 'trans' regulation across the subgenomes. ARO10 transcript levels showed a poor correlation with decarboxylase activities. These results provide insights into flavour formation in S. pastorianus and illustrate the complexity of functional characterization in aneuploid strains.

  10. Development of a Novel Cysteine Sulfinic Acid Decarboxylase Knockout Mouse: Dietary Taurine Reduces Neonatal Mortality

    Directory of Open Access Journals (Sweden)

    Eunkyue Park

    2014-01-01

    Full Text Available We engineered a CSAD KO mouse to investigate the physiological roles of taurine. The disruption of the CSAD gene was verified by Southern, Northern, and Western blotting. HPLC indicated an 83% decrease of taurine concentration in the plasma of CSAD-/-. Although CSAD-/- generation (G1 and G2 survived, offspring from G2 CSAD-/- had low brain and liver taurine concentrations and most died within 24 hrs of birth. Taurine concentrations in G3 CSAD-/- born from G2 CSAD-/- treated with taurine in the drinking water were restored and survival rates of G3 CSAD-/- increased from 15% to 92%. The mRNA expression of CDO, ADO, and TauT was not different in CSAD-/- compared to WT and CSAD mRNA was not expressed in CSAD-/-. Expression of Gpx 1 and 3 was increased significantly in CSAD-/- and restored to normal levels with taurine supplementation. Lactoferrin and the prolactin receptor were significantly decreased in CSAD-/-. The prolactin receptor was restored with taurine supplementation. These data indicated that CSAD KO is a good model for studying the effects of taurine deficiency and its treatment with taurine supplementation.

  11. Quantitative in situ hybridization analysis of glutamic acid decarboxylase messenger RNA in developing rat cerebellum.

    Science.gov (United States)

    Willcutts, M D; Morrison-Bogorad, M

    1991-11-19

    The appearance and relative amounts of GAD mRNA in rat cerebellar neurons during postnatal development was studied by in situ hybridization. GAD mRNA content within all GABAergic neurons increased during the first month of postnatal development, but the degree and time course of the increase varied among different neuronal types. In newborn rats, GAD mRNA was present only in the prenatally-formed Purkinje and Golgi cells. GAD mRNA in Golgi cells had reached adult levels by postnatal day 14, while GAD mRNA levels in Purkinje cells reached adult levels one week later. Most basket cells expressed GAD mRNA by postnatal day 14, and final levels were attained one week later. Stellate cells in the bottom two-thirds of the molecular layer attained their final GAD mRNA content by postnatal day 21 whereas stellate cells in close proximity to the pial surface were not yet mature at this age. No GAD mRNA was detected within the external granular layer at any time during development. In adult rat, approximately 40% of cerebellar GAD mRNA was contained within the Purkinje cell population, 38% within the stellate cells, 17% within the basket cells, and only 5% within the Golgi cells. Increases in GAD mRNA within GABAergic neurons during cerebellar development correlated with the timing of neuronal maturation and synaptogenesis in these cell populations, suggesting that synaptic activity affects GAD gene expression in developing cerebellum.

  12. Role of the proteasome in excitotoxicity-induced cleavage of glutamic acid decarboxylase in cultured hippocampal neurons.

    Directory of Open Access Journals (Sweden)

    Márcio S Baptista

    Full Text Available Glutamic acid decarboxylase is responsible for synthesizing GABA, the major inhibitory neurotransmitter, and exists in two isoforms--GAD65 and GAD67. The enzyme is cleaved under excitotoxic conditions, but the mechanisms involved and the functional consequences are not fully elucidated. We found that excitotoxic stimulation of cultured hippocampal neurons with glutamate leads to a time-dependent cleavage of GAD65 and GAD67 in the N-terminal region of the proteins, and decrease the corresponding mRNAs. The cleavage of GAD67 was sensitive to the proteasome inhibitors MG132, YU102 and lactacystin, and was also abrogated by the E1 ubiquitin ligase inhibitor UBEI-41. In contrast, MG132 and UBEI-41 were the only inhibitors tested that showed an effect on GAD65 cleavage. Excitotoxic stimulation with glutamate also increased the amount of GAD captured in experiments where ubiquitinated proteins and their binding partners were isolated. However, no evidences were found for direct GADs ubiquitination in cultured hippocampal neurons, and recombinant GAD65 was not cleaved by purified 20S or 26S proteasome preparations. Since calpains, a group of calcium activated proteases, play a key role in GAD65/67 cleavage under excitotoxic conditions the results suggest that GADs are cleaved after ubiquitination and degradation of an unknown binding partner by the proteasome. The characteristic punctate distribution of GAD65 along neurites of differentiated cultured hippocampal neurons was significantly reduced after excitotoxic injury, and the total GAD activity measured in extracts from the cerebellum or cerebral cortex at 24h postmortem (when there is a partial cleavage of GADs was also decreased. The results show a role of the UPS in the cleavage of GAD65/67 and point out the deregulation of GADs under excitotoxic conditions, which is likely to affect GABAergic neurotransmission. This is the first time that the UPS has been implicated in the events triggered during

  13. Assessment of the effects of glutamic acid decarboxylase antibodies and trace elements on cognitive performance in older adults

    Directory of Open Access Journals (Sweden)

    Alghadir AH

    2015-12-01

    Full Text Available Ahmad H Alghadir,1 Sami A Gabr,1,2 Einas Al-Eisa11Department of Rehabilitation Sciences, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia; 2Department of Anatomy, Faculty of Medicine, Mansoura University, Mansoura, EgyptBackground: Homeostatic imbalance of trace elements such as iron (Fe, copper (Cu, and zinc (Zn demonstrated adverse effects on brain function among older adults.Objective: The present study aimed to investigate the effects of trace elements and the presence of anti-glutamic acid decarboxylase antibodies (GADAs in human cognitive abilities among healthy older adults.Methods: A total of 100 healthy subjects (65 males, 35 females; age range; 64–96 years were recruited for this study. Based on Loewenstein Occupational Therapy Cognitive Assessment (LOTCA score, the participants were classified according to cognitive performance into normal (n=45, moderate (n=30, and severe (n=25. Cognitive functioning, leisure-time physical activity (LTPA, serum trace elements – Fe, Cu, Zn, Zn/Cu, and GADAs were assessed using LOTCA battery, pre-validated physical activity (PA questionnaire, atomic absorption, and immunoassay techniques, respectively.Results: Approximately 45% of the study population (n=45 had normal distribution of cognitive function and 55% of the study population (n=55 had abnormal cognitive function; they were classified into moderate (score 62–92 and severe (score 31–62. There was a significant reduction in the level of Zn and Zn/Cu ratio along with an increase in the level of Fe, Cu, and anti-GADAs in subjects of severe (P=0.01 and moderate (P=0.01 cognitive performance. LOTCA-cognitive scores correlated positively with sex, HbA1c, Fe, Cu, Zn, and Zn/Cu ratio, and negatively with age, PA, body mass index, and anti-GADAs. Significant inter-correlation was reported between serum trace element concentrations and anti-GADAs which suggest producing a cognitive decline via oxidative and neural

  14. Immunohistochemical expression of ornithine decarboxylase, diamine oxidase, putrescine, and spermine in normal canine enterocolic mucosa, in chronic colitis, and in colorectal cancer.

    Science.gov (United States)

    Rossi, Giacomo; Cerquetella, Matteo; Pengo, Graziano; Mari, Subeide; Balint, Emilia; Bassotti, Gabrio; Manolescu, Nicolae

    2015-01-01

    We compared the immunohistochemical expression of putrescine (PUT), spermine (SPM), ornithine decarboxylase (ODC), and diamine oxidase (DAO) in bioptic samples of canine colonic mucosa with chronic inflammation (i.e., granulomatous colitis and lymphoplasmacytic colitis) or neoplasia. Single and total polyamines levels were significantly higher in neoplastic tissue than in normal samples. Samples with different degrees of inflammation showed a general decrease expression of ODC if compared to controls; SPM was practically not expressed in control samples and very low in samples with chronic-granulomatous inflammation. In carcinomatous samples, the ODC activity was higher with respect to controls and samples with inflammation. This is the first description of polyamines expression in dog colonic mucosa in normal and in different pathological conditions, suggesting that the balance between polyamine degradation and biosynthesis is evidently disengaged during neoplasia.

  15. Immunohistochemical Expression of Ornithine Decarboxylase, Diamine Oxidase, Putrescine, and Spermine in Normal Canine Enterocolic Mucosa, in Chronic Colitis, and in Colorectal Cancer

    Directory of Open Access Journals (Sweden)

    Giacomo Rossi

    2015-01-01

    Full Text Available We compared the immunohistochemical expression of putrescine (PUT, spermine (SPM, ornithine decarboxylase (ODC, and diamine oxidase (DAO in bioptic samples of canine colonic mucosa with chronic inflammation (i.e., granulomatous colitis and lymphoplasmacytic colitis or neoplasia. Single and total polyamines levels were significantly higher in neoplastic tissue than in normal samples. Samples with different degrees of inflammation showed a general decrease expression of ODC if compared to controls; SPM was practically not expressed in control samples and very low in samples with chronic-granulomatous inflammation. In carcinomatous samples, the ODC activity was higher with respect to controls and samples with inflammation. This is the first description of polyamines expression in dog colonic mucosa in normal and in different pathological conditions, suggesting that the balance between polyamine degradation and biosynthesis is evidently disengaged during neoplasia.

  16. Anti-Yo and anti-glutamic acid decarboxylase antibodies presenting in carcinoma of the uterus with paraneoplastic cerebellar degeneration: a case report

    Directory of Open Access Journals (Sweden)

    Panegyres Peter K

    2012-06-01

    Full Text Available Abstract Introduction Paraneoplastic cerebellar degeneration is a rare non-metastatic manifestation of malignancy. In this report, to the best of our knowledge we describe for the first time a diagnosis of paraneoplastic cerebellar degeneration several months prior to the diagnosis of clear carcinoma of the uterus. Case presentation A 75-year-old Caucasian woman manifested a rapidly progressive cerebellar syndrome with nystagmus, past-pointing, dysdiadochokinesis, dysarthria, truncal ataxia and titubation. The paraneoplastic cerebellar degeneration was associated with anti-Yo and anti-glutamic acid decarboxylase antibodies. 14-3-3 protein was detected in the cerebrospinal fluid. She was treated with intravenous immunoglobulin prior to laparotomy, hysterectomy and bilateral salpingoophorectomy. Our patient has survived for three years following diagnosis and treatment. Conclusions To the best of our knowledge this is the first report of an association of clear cell carcinoma of the uterus and paraneoplastic cerebellar degeneration with both anti-Yo and anti-glutamic acid decarboxylase antibodies. The findings imply that both antibodies contributed to the fulminating paraneoplastic cerebellar degeneration observed in our patient, and this was of such severity it resulted in the release of 14-3-3 protein in the cerebrospinal fluid, a marker of neuronal death.

  17. Elimination of islet cell antibodies and glutamic acid decarboxylase antibodies II in a patient with newly diagnosed insulin-dependent diabetes mellitus.

    Science.gov (United States)

    Richter, W O; Donner, M G; Schwandt, P

    1997-01-01

    Islet cell antibodies and glutamic acid decarboxylase II (GAD II) antibodies have been discussed in the autoimmune pathogenesis of insulin-dependent diabetes mellitus (IDDM). Hence, immunosuppressants, intravenous immunoglobulins, and plasmapheresis have been used in an effort to modulate autoimmune activity and thereby prevent the destruction of pancreatic beta-cells. We describe the autoantibody (islet cell antibody and GAD II) kinetics and clinical course in a patient with newly diagnosed IDDM treated with a specific immunoglobulin apheresis technique. Five days after the initial diagnosis a 37-year-old patient with IDDM underwent a series of seven immunoglobulin aphereses. Immunoglobulin (IgG, IgA, IgM), islet cell antibody, GAD II, and C-peptide concentrations were monitored for a time course of 74 days. Daily insulin requirements were recorded. One single immunoglobulin apheresis decreased IgG by 66.2 +/- 9.1%, IgA by 66.8 +/- 8.7%, and IgM by 57.7 +/- 12.9%. GAD II antibodies were reduced by 61.9 +/- 12.4%. The islet cell antibody titer declined from 1:32 to 1:4 after the treatment series. There were no relevant changes in the safety parameters determined nor were there any clinical side effects. The efficient decrease in islet cell antibodies and glutamic acid decarboxylase II antibodies in a patient with IDDM encourages further investigations into the impact of this treatment on the clinical course of this autoimmune disorder.

  18. Hemin inhibits cyclooxygenase-2 expression through nuclear factor-kappa B activation and ornithine decarboxylase expression in 12-O-tetradecanoylphorbol-13-acetate-treated mouse skin

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jae Hee; Lee, Chang Ki [Department of Oral Biology, Yonsei University College of Dentistry, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-752 (Korea, Republic of); Oral Cancer Research Institute, Yonsei University College of Dentistry, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-752 (Korea, Republic of); Hwang, Young Sun [Department of Applied Life Science and Brain Korea 21 Project, Yonsei University College of Dentistry, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-752 (Korea, Republic of); Park, Kwang-Kyun [Department of Oral Biology, Yonsei University College of Dentistry, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-752 (Korea, Republic of); Department of Applied Life Science and Brain Korea 21 Project, Yonsei University College of Dentistry, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-752 (Korea, Republic of); Chung, Won-Yoon [Department of Oral Biology, Yonsei University College of Dentistry, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-752 (Korea, Republic of); Department of Applied Life Science and Brain Korea 21 Project, Yonsei University College of Dentistry, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-752 (Korea, Republic of)], E-mail: wychung@yuhs.ac

    2008-07-03

    Inflammation induced by various stimuli has been found to be associated with increased risk for most types of human cancer. Inflammation facilitates the initiation of normal cells, as well as the growth of initiated cells and their progression to malignancy through production of proinflammatory cytokines and diverse reactive oxygen/nitrogen species. These also activate the signaling molecules that are involved in inflammation and carcinogenesis. Our previous studies have demonstrated that hemin inhibited 7,12-dimethylbenz[a]anthracene (DMBA)-induced bacterial mutagenesis and oxidative DNA damage, reduced the level of DNA-DMBA adduct and 12-O-tetradecanoylphorobl-13-acetate (TPA)-induced tumor formation in DMBA-initiated ICR mouse skin, and inhibited myeloperoxidase and ornithine decarboxylase (ODC) activity and H{sub 2}O{sub 2} formation in TPA-treated mouse skin. In the present study, to further elucidate the molecular mechanisms underlying the chemopreventive activity of hemin, its effect on the expression of ODC and cyclooxygenase (COX)-2, and the activation of nuclear factor-kappa B (NF-{kappa}B) and mitogen-activated protein kinases (MAPKs) regulating these proteins were explored in mouse skin with TPA-induced inflammation. Topically applied hemin inhibited ear edema and epidermal thickness in mice treated with TPA. Pretreatment with hemin reduced the expression of ODC and COX-2, and also reduced NF-{kappa}B activation in TPA-stimulated mouse skin. In addition, hemin suppressed the TPA-induced activation of extracellular signal-regulated protein kinase (ERK) and p38 MAPK in a dose-dependent manner. Taken together, hemin inhibited TPA-induced COX-2 expression by altering NF-{kappa}B signaling pathway via ERK and p38 MAPK, as well as TPA-induced ODC expression in mouse skin. Thereby, hemin may be an attractive candidate for a chemopreventive agent.

  19. Active site directed irreversible inactivation of brewers' yeast pyruvate decarboxylase by the conjugated substrate analogue (E)-4-(4-chlorophenyl)-2-oxo-3-butenoic acid: development of a suicide substrate.

    Science.gov (United States)

    Kuo, D J; Jordan, F

    1983-08-01

    (E)-4-(4-Chlorophenyl)-2-oxo-3-butenoic acid (CPB) was found to irreversibly inactivate brewers' yeast pyruvate decarboxylase (PDC, EC 4.1.1.1) in a biphasic, sigmoidal manner, as is found for the kinetic behavior of substrate. An expression was derived for two-site irreversible inhibition of allosteric enzymes, and the kinetic behavior of CPB fit the expression for two-site binding. The calculated Ki's of 0.7 mM and 0.3 mM for CPB were assigned to the catalytic site and the regulatory site, respectively. The presence of pyruvic acid at high concentrations protected PDC from inactivation, whereas low concentrations of pyruvic acid accelerated inactivation by CPB. Pyruvamide, a known allosteric activator of PDC, was found to enhance inactivation by CPB. The results can be explained if pyruvamide binds only to a regulatory site, but CPB and pyruvic acid compete for both the regulatory and the catalytic centers. [1-14C]CPB was found to lose 14CO2 concurrently with the inactivation of the enzyme. Therefore, CPB was being turned over by PDC, in addition to inactivating it. CPB can be labeled a suicide-type inactivator for PDC.

  20. Immunocytochemical localization of glutamic acid decarboxylase (GAD) and glutamine synthetase (GS) in the area postrema of the cat. Light and electron microscopy

    Science.gov (United States)

    D'Amelio, Fernando E.; Mehler, William R.; Gibbs, Michael A.; Eng, Lawrence F.; Wu, Jang-Yen

    1987-01-01

    Morphological evidence is presented of the existence of the putative neurotransmitter gamma-aminobutyric acid (GABA) in axon terminals and of glutamine synthetase (GS) in ependymoglial cells and astroglial components of the area postrema (AP) of the cat. Purified antiserum directed against the GABA biosynthetic enzyme glutamic acid decarboxylase (GAD) and GS antiserum were used. The results showed that punctate structures of variable size corresponding to axon terminals exhibited GAD-immunoreactivity and were distributed in varying densities. The greatest accumulation occurred in the caudal and middle segment of the AP and particularly in the area subpostrema, where the aggregation of terminals was extremely dense. The presence of both GAD-immunoreactive profiles and GS-immunostained ependymoglial cells and astrocytes in the AP provide further evidence of the functional correlation between the two enzymes.

  1. Impact of Cell-free Supernatant of Lactic Acid Bacteria on Putrescine and Other Polyamine Formation by Foodborne Pathogens in Ornithine Decarboxylase Broth.

    Science.gov (United States)

    Ozogul, Fatih; Tabanelli, Giulia; Toy, Nurten; Gardini, Fausto

    2015-06-24

    Conversion of ornithine to putrescine by Salmonella Paratyphi A, Listeria monocytogenes, Staphylococcus aureus, and Escherichia coli was investigated in ornithine decarboxylase broth (ODB) using cell-free supernatants (CFSs) obtained from Leuconostoc mesenterodies subsp. cremoris, Pediococcus acidilactici, Lactococcus lactis subsp. lactis, Streptococcus thermophilus. Two groups of cell-free supernatants (25 or 50%) and control (only ODB) were prepared to investigate putrescine (PUT) and other polyamine formation by foodborne pathogens (FBPs). Significant differences (p < 0.05) were observed among the species for each amine. All of the CFSs reduced the formation of PUT by ≥65%. The production of cadaverine (CAD) was scarcely affected by the presence of CFSs, with the exception of the samples inoculated with L. monocytogenes. The variation in polyamine was found with respect to the control samples. Spermidine (SPD) was produced in lower amount in many samples, especially in Gram-negative FBPs, whereas spermine (SPN) increased drastically in the major part of the samples concerning the control. Histamine (HIS) was characterized by a marked concentration decrease in all of the samples, and tyramine (TYR) was accumulated in very low concentrations in the controls. Therefore, the ability of bacteria to produce certain biogenic amines such as HIS, TYR, PUT, and CAD has been studied to assess their risk and prevent their formation in food products. The results obtained from this study concluded that the lactic acid bacteria (LAB) strains with non-decarboxylase activity are capable of avoiding or limiting biogenic amine formation by FBP.

  2. Occurrence of Type 1 Diabetes in Graves' Disease Patients Who Are Positive for Antiglutamic Acid Decarboxylase Antibodies: An 8-Year Followup Study

    Directory of Open Access Journals (Sweden)

    Matsuo Taniyama

    2011-01-01

    Full Text Available Glutamic acid decarboxylase antibodies (GADAs are one of the markers of islet cell autoimmunity and are sometimes present before the onset of type 1 diabetes (T1D. GADA can be present in Graves' patients without diabetes; however, the outcome of GADA-positive Graves' patients is not fully understood, and the predictive value of GADA for the development of T1D in Graves' patients remains to be clarified. We investigated the prevalence of GADA in 158 patients with Graves' disease and detected GADA in 10 patients. They were followed up to discover whether or not T1D developed. In the course of eight years, 2 patients with high titers of GADA developed T1D, both had long-standing antithyroid drug-resistant Graves' disease. Thus, Graves' disease with high GADA titer seems to be at high risk for T1D.

  3. Efficient production of gamma-aminobutyric acid using Escherichia coli by co-localization of glutamate synthase, glutamate decarboxylase, and GABA transporter.

    Science.gov (United States)

    Dung Pham, Van; Somasundaram, Sivachandiran; Lee, Seung Hwan; Park, Si Jae; Hong, Soon Ho

    2016-01-01

    Gamma-aminobutyric acid (GABA) is an important bio-product, which is used in pharmaceutical formulations, nutritional supplements, and biopolymer monomer. The traditional GABA process involves the decarboxylation of glutamate. However, the direct production of GABA from glucose is a more efficient process. To construct the recombinant strains of Escherichia coli, a novel synthetic scaffold was introduced. By carrying out the co-localization of glutamate synthase, glutamate decarboxylase, and GABA transporter, we redirected the TCA cycle flux to GABA pathway. The genetically engineered E. coli strain produced 1.08 g/L of GABA from 10 g/L of initial glucose. Thus, with the introduction of a synthetic scaffold, we increased GABA production by 2.2-fold. The final GABA concentration was increased by 21.8% by inactivating competing pathways.

  4. Exogenous γ-aminobutyric acid (GABA) affects pollen tube growth via modulating putative Ca2+-permeable membrane channels and is coupled to negative regulation on glutamate decarboxylase.

    Science.gov (United States)

    Yu, Guang-Hui; Zou, Jie; Feng, Jing; Peng, Xiong-Bo; Wu, Ju-You; Wu, Ying-Liang; Palanivelu, Ravishankar; Sun, Meng-Xiang

    2014-07-01

    γ-Aminobutyric acid (GABA) is implicated in pollen tube growth, but the molecular and cellular mechanisms that it mediates are largely unknown. Here, it is shown that exogenous GABA modulates putative Ca(2+)-permeable channels on the plasma membranes of tobacco pollen grains and pollen tubes. Whole-cell voltage-clamp experiments and non-invasive micromeasurement technology (NMT) revealed that the influx of Ca(2+) increases in pollen tubes in response to exogenous GABA. It is also demonstrated that glutamate decarboxylase (GAD), the rate-limiting enzyme of GABA biosynthesis, is involved in feedback controls of Ca(2+)-permeable channels to fluctuate intracellular GABA levels and thus modulate pollen tube growth. The findings suggest that GAD activity linked with Ca(2+)-permeable channels relays an extracellular GABA signal and integrates multiple signal pathways to modulate tobacco pollen tube growth. Thus, the data explain how GABA mediates the communication between the style and the growing pollen tubes.

  5. Spinal cord hemisection facilitates aromatic L-amino acid decarboxylase cells to produce serotonin in the subchronic but not the chronic phase

    DEFF Research Database (Denmark)

    Azam, Bushra; Wienecke, Jacob; Jensen, Dennis Bo;

    2015-01-01

    12) were used with a postoperation interval at 5 days or 60 days. Using immunohistochemistry, first, we observed a significant reduction in the density of 5-HT-immunoreactive fibers in the spinal cord below the lesion on the injured side for both groups. Second, we found that the AADC cells were......Neuromodulators, such as serotonin (5-hydroxytryptamine, 5-HT) and noradrenalin, play an essential role in regulating the motor and sensory functions in the spinal cord. We have previously shown that in the rat spinal cord the activity of aromatic L-amino acid decarboxylase (AADC) cells to produce...... 5-HT from its precursor (5-hydroxytryptophan, 5-HTP) is dramatically increased following complete spinal cord transection. In this study, we investigated whether a partial loss of 5-HT innervation could similarly increase AADC activity. Adult rats with spinal cord hemisected at thoracic level (T11/T...

  6. Synergistic and antagonistic effect of lactic acid bacteria on tyramine production by food-borne pathogenic bacteria in tyrosine decarboxylase broth.

    Science.gov (United States)

    Kuley, Esmeray; Ozogul, Fatih

    2011-08-01

    The effect of lactic acid bacteria (LAB) strains on tyramine (TYR) and also other biogenic amines (BA) production by eight common food-borne pathogen (FBP) in tyrosine decarboxylase broth (TDB) was investigated by using a rapid HPLC method. Significant differences were observed among the FBP strains in ammonia (AMN) and BA production apart from tryptamine, histamine (HIS) and spermine formation (pfood-borne pathogenic bacteria, although the effect of some LAB strains on BA production was strain-dependent. Lactococcus spp. and Streptococcus spp. resulted in significantly higher TYR accumulation by Aeromonas hydrophila and Enterococcus faecalis in TDB. The presence of Lactococcus and/or Lactobacillus in TDB significantly increased HIS production by A. hydrophila, Escherichia coli, Ent. faecalis, Klebsiella pneumoniae and Pseudomonas aeruginosa, whereas HIS accumulation was significantly reduced by Staphylococcus aureus, S. paratyphi A and Listeria monocytogenes.

  7. Glutamate and GABA-metabolizing enzymes in post-mortem cerebellum in Alzheimer's disease: phosphate-activated glutaminase and glutamic acid decarboxylase.

    Science.gov (United States)

    Burbaeva, G Sh; Boksha, I S; Tereshkina, E B; Savushkina, O K; Prokhorova, T A; Vorobyeva, E A

    2014-10-01

    Enzymes of glutamate and GABA metabolism in postmortem cerebellum from patients with Alzheimer's disease (AD) have not been comprehensively studied. The present work reports results of original comparative study on levels of phosphate-activated glutaminase (PAG) and glutamic acid decarboxylase isoenzymes (GAD65/67) in autopsied cerebellum samples from AD patients and matched controls (13 cases in each group) as well as summarizes published evidence for altered levels of PAG and GAD65/67 in AD brain. Altered (decreased) levels of these enzymes and changes in links between amounts of these enzymes and other glutamate-metabolizing enzymes (such as glutamate dehydrogenase and glutamine synthetase-like protein) in AD cerebella suggest significantly impaired glutamate and GABA metabolism in this brain region, which was previously regarded as not substantially involved in AD pathogenesis.

  8. Loss of autonoetic consciousness of recent autobiographical episodes and accelerated long-term forgetting in a patient with previously unrecognized glutamic acid decarboxylase antibody related limbic encephalitis

    Directory of Open Access Journals (Sweden)

    Juri-Alexander eWitt

    2015-06-01

    Full Text Available We describe a 35-year old male patient presenting with depressed mood and emotional instability who complained about severe anterograde and retrograde memory deficits characterized by accelerated long-term forgetting and loss of autonoetic consciousness regarding autobiographical memories of the last three years. Months before he had experienced two breakdowns of unknown etiology giving rise to the differential diagnosis of epileptic seizures after various practitioners and clinics had suggested different etiologies such as a psychosomatic condition, burnout, depression or dissociative amnesia. Neuropsychological assessment indicated selectively impaired figural memory performance. Extended diagnostics confirmed accelerated forgetting of previously learned and retrievable verbal material. Structural imaging showed bilateral swelling and signal alterations of temporomesial structures (left > right. Video-EEG monitoring revealed a left temporal epileptic focus and subclincal seizure, but no overt seizures. Antibody tests in serum and liquor were positive for glutamic acid decarboxylase antibodies. These findings led to the diagnosis of glutamic acid decarboxylase antibody related limbic encephalitis. Monthly steroid pulses over six months led to recovery of subjective memory and to intermediate improvement but subsequent worsening of objective memory performance. During the course of treatment the patient reported de novo paroxysmal non-responsive states. Thus, antiepileptic treatment was started and the patient finally became seizure free. At the last visit vocational reintegration was successfully in progress.In conclusion, amygdala swelling, retrograde biographic memory impairment, accelerated long-term forgetting and emotional instability may serve as indicators of limbic encephalitis, even in the absence of overt epileptic seizures. The monitoring of such patients calls for a standardized and concerted multilevel diagnostic approach with

  9. Glutamic acid decarboxylase antibodies are indicators of the course, but not of the onset, of diabetes in middle-aged adults: the Atherosclerosis Risk in Communities Study

    Directory of Open Access Journals (Sweden)

    A. Vigo

    2007-07-01

    Full Text Available To efficiently examine the association of glutamic acid decarboxylase antibody (GADA positivity with the onset and progression of diabetes in middle-aged adults, we performed a case-cohort study representing the ~9-year experience of 10,275 Atherosclerosis Risk in Communities Study participants, initially aged 45-64 years. Antibodies to glutamic acid decarboxylase (GAD65 were measured by radioimmunoassay in 580 incident diabetes cases and 544 non-cases. The overall weighted prevalence of GADA positivity (³1 U/mL was 7.3%. Baseline risk factors, with the exception of smoking and interleukin-6 (P £ 0.02, were generally similar between GADA-positive and -negative individuals. GADA positivity did not predict incident diabetes in multiply adjusted (HR = 1.04; 95%CI = 0.55, 1.96 proportional hazard analyses. However, a small non-significant adjusted risk (HR = 1.29; 95%CI = 0.58, 2.88 was seen for those in the highest tertile (³2.38 U/mL of positivity. GADA-positive and GADA-negative non-diabetic individuals had similar risk profiles for diabetes, with central obesity and elevated inflammation markers, aside from glucose, being the main predictors. Among diabetes cases at study's end, progression to insulin treatment increased monotonically as a function of baseline GADA level. Overall, being GADA positive increased risk of progression to insulin use almost 10 times (HR = 9.9; 95%CI = 3.4, 28.5. In conclusion, in initially non-diabetic middle-aged adults, GADA positivity did not increase diabetes risk, and the overall baseline profile of risk factors was similar for positive and negative individuals. Among middle-aged adults, with the possible exception of those with the highest GADA levels, autoimmune pathophysiology reflected by GADA may become clinically relevant only after diabetes onset.

  10. 13C magnetic resonance spectroscopy measurements with hyperpolarized [1‐13C] pyruvate can be used to detect the expression of transgenic pyruvate decarboxylase activity in vivo

    Science.gov (United States)

    Dzien, Piotr; Tee, Sui‐Seng; Kettunen, Mikko I.; Lyons, Scott K.; Larkin, Timothy J.; Timm, Kerstin N.; Hu, De‐En; Wright, Alan; Rodrigues, Tiago B.; Serrao, Eva M.; Marco‐Rius, Irene; Mannion, Elizabeth; D'Santos, Paula; Kennedy, Brett W. C.

    2015-01-01

    Purpose Dissolution dynamic nuclear polarization can increase the sensitivity of the 13C magnetic resonance spectroscopy experiment by at least four orders of magnitude and offers a novel approach to the development of MRI gene reporters based on enzymes that metabolize 13C‐labeled tracers. We describe here a gene reporter based on the enzyme pyruvate decarboxylase (EC 4.1.1.1), which catalyzes the decarboxylation of pyruvate to produce acetaldehyde and carbon dioxide. Methods Pyruvate decarboxylase from Zymomonas mobilis (zmPDC) and a mutant that lacked enzyme activity were expressed using an inducible promoter in human embryonic kidney (HEK293T) cells. Enzyme activity was measured in the cells and in xenografts derived from the cells using 13C MRS measurements of the conversion of hyperpolarized [1‐13C] pyruvate to H13 CO3–. Results Induction of zmPDC expression in the cells and in the xenografts derived from them resulted in an approximately two‐fold increase in the H13 CO3–/[1‐13C] pyruvate signal ratio following intravenous injection of hyperpolarized [1‐13C] pyruvate. Conclusion We have demonstrated the feasibility of using zmPDC as an in vivo reporter gene for use with hyperpolarized 13C MRS. Magn Reson Med 76:391–401, 2016. © 2015 The Authors. Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. PMID:26388418

  11. Application of Glutamic Acid Decarboxylase Antibody Test in Children with Diabetes%谷氨酸脱羧酶抗体检测在儿童糖尿病中的应用

    Institute of Scientific and Technical Information of China (English)

    贺岩

    2015-01-01

    Objective To explore the application value of detection of glutamic acid decarboxylase antibody in children with diabetes in. Methods Select the January 2013, 2015 years 1 month in the hospital of glutamic acid decarboxylase antibody detection of 97 cases of diabetes mellitus patients as the observation group, and the selection of 97 cases of normal children as control group, on the two groups of glutamic acid decarboxylase antibody positive rate. Results After testing, observation group of glutamic acid decarboxylase antibody positive rate was 97.9%, control group of glutamic acid decarboxylase anti-body positive rate was 0, two groups compared with statistical significance (P<0.05). Conclusion Glutamic acid decarboxy-lase antibody detection of children with type 1 diabetes diagnosis has important clinical significance, it is worth in the clini-cal application.%目的:探讨谷氨酸脱羧酶抗体检测在儿童糖尿病中的应用价值。方法选取2013年1月-2015年1月在医院进行谷氨酸脱羧酶抗体检测的97例糖尿病患儿作为观察组,并选取97例正常儿童作为对照组,对两组谷氨酸脱羧酶抗体阳性率做比较。结果经过检测后,观察组谷氨酸脱羧酶抗体阳性率为97.9%,对照组谷氨酸脱羧酶抗体阳性率为0,两组比较差异具有统计学意义(P<0.05)。结论进行谷氨酸脱羧酶抗体检测对儿童1型糖尿病的诊断具有重大的临床意义,值得在临床上推广应用。

  12. Cell-specific expression of tryptophan decarboxylase and 10-hydroxygeraniol oxidoreductase, key genes involved in camptothecin biosynthesis in Camptotheca acuminata Decne (Nyssaceae

    Directory of Open Access Journals (Sweden)

    Santamaria Anna

    2010-04-01

    Full Text Available Abstract Background Camptotheca acuminata is a major natural source of the terpenoid indole alkaloid camptothecin (CPT. At present, little is known about the cellular distribution of the biosynthesis of CPT, which would be useful knowledge for developing new strategies and technologies for improving alkaloid production. Results The pattern of CPT accumulation was compared with the expression pattern of some genes involved in CPT biosynthesis in C. acuminata [i.e., Ca-TDC1 and Ca-TDC2 (encoding for tryptophan decarboxylase and Ca-HGO (encoding for 10-hydroxygeraniol oxidoreductase]. Both CPT accumulation and gene expression were investigated in plants at different degrees of development and in plantlets subjected to drought-stress. In all organs, CPT accumulation was detected in epidermal idioblasts, in some glandular trichomes, and in groups of idioblast cells localized in parenchyma tissues. Drought-stress caused an increase in CPT accumulation and in the number of glandular trichomes containing CPT, whereas no increase in epidermal or parenchymatous idioblasts was observed. In the leaf, Ca-TDC1 expression was detected in some epidermal cells and in groups of mesophyll cells but not in glandular trichomes; in the stem, it was observed in parenchyma cells of the vascular tissue; in the root, no expression was detected. Ca-TDC2 expression was observed exclusively in leaves of plantlets subjected to drought-stress, in the same sites described for Ca-TDC1. In the leaf, Ca-HGO was detected in all chlorenchyma cells; in the stem, it was observed in the same sites described for Ca-TDC1; in the root, no expression was detected. Conclusions The finding that the sites of CPT accumulation are not consistently the same as those in which the studied genes are expressed demonstrates an organ-to-organ and cell-to-cell translocation of CPT or its precursors.

  13. Efficient gamma-aminobutyric acid bioconversion by employing synthetic complex between glutamate decarboxylase and glutamate/GABA antiporter in engineered Escherichia coli.

    Science.gov (United States)

    Le Vo, Tam Dinh; Ko, Ji-seun; Park, Si Jae; Lee, Seung Hwan; Hong, Soon Ho

    2013-08-01

    Gamma-aminobutyric acid (GABA) is a precursor of one of the most promising heat-resistant biopolymers, Nylon-4, and can be produced by the decarboxylation of monosodium glutamate (MSG). In this study, a synthetic protein complex was applied to improve the GABA conversion in engineered Escherichia coli. Complexes were constructed by assembling a single protein-protein interaction domain SH3 to the glutamate decarboxylase (GadA and GadB) and attaching a cognate peptide ligand to the glutamate/GABA antiporter (GadC) at the N-terminus, C-terminus, and the 233rd amino acid residue. When GadA and GadC were co-overexpressed via the C-terminus complex, a GABA concentration of 5.65 g/l was obtained from 10 g/l MSG, which corresponds to a GABA yield of 93 %. A significant increase of the GABA productivity was also observed where the GABA productivity increased 2.5-fold in the early culture period due to the introduction of the synthetic protein complex. The GABA pathway efficiency and GABA productivity were enhanced by the introduction of the complex between Gad and glutamate/GABA antiporter.

  14. Expression of an oxalate decarboxylase impairs the necrotic effect induced by Nep1-like protein (NLP) of Moniliophthora perniciosa in transgenic tobacco.

    Science.gov (United States)

    da Silva, Leonardo F; Dias, Cristiano V; Cidade, Luciana C; Mendes, Juliano S; Pirovani, Carlos P; Alvim, Fátima C; Pereira, Gonçalo A G; Aragão, Francisco J L; Cascardo, Júlio C M; Costa, Marcio G C

    2011-07-01

    Oxalic acid (OA) and Nep1-like proteins (NLP) are recognized as elicitors of programmed cell death (PCD) in plants, which is crucial for the pathogenic success of necrotrophic plant pathogens and involves reactive oxygen species (ROS). To determine the importance of oxalate as a source of ROS for OA- and NLP-induced cell death, a full-length cDNA coding for an oxalate decarboxylase (FvOXDC) from the basidiomycete Flammulina velutipes, which converts OA into CO(2) and formate, was overexpressed in tobacco plants. The transgenic plants contained less OA and more formic acid compared with the control plants and showed enhanced resistance to cell death induced by exogenous OA and MpNEP2, an NLP of the hemibiotrophic fungus Moniliophthora perniciosa. This resistance was correlated with the inhibition of ROS formation in the transgenic plants inoculated with OA, MpNEP2, or a combination of both PCD elicitors. Taken together, these results have established a pivotal function for oxalate as a source of ROS required for the PCD-inducing activity of OA and NLP. The results also indicate that FvOXDC represents a potentially novel source of resistance against OA- and NLP-producing pathogens such as M. perniciosa, the causal agent of witches' broom disease of cacao (Theobroma cacao L.).

  15. Tyrosine decarboxylase activity of enterococci grown in media with different nutritional potential: tyramine and 2-phenylethylamine accumulation and tyrDC gene expression.

    Science.gov (United States)

    Bargossi, Eleonora; Tabanelli, Giulia; Montanari, Chiara; Lanciotti, Rosalba; Gatto, Veronica; Gardini, Fausto; Torriani, Sandra

    2015-01-01

    The ability to accumulate tyramine and 2-phenylethylamine by two strains of Enterococcus faecalis and two strains Enterococcus faecium was evaluated in two cultural media added or not with tyrosine. All the enterococcal strains possessed a tyrosine decarboxylase (tyrDC) which determined tyramine accumulation in all the conditions tested, independently on the addition of high concentration of free tyrosine. Enterococci differed in rate and level of biogenic amines accumulation. E. faecalis EF37 and E. faecium FC12 produced tyramine in high amount since the exponential growth phase, while 2-phenylethylamine was accumulated when tyrosine was depleted. E. faecium FC12 and E. faecalis ATCC 29212 showed a slower tyraminogenic activity which took place mainly in the stationary phase up to 72 h of incubation. Moreover, E. faecalis ATCC 29212 produced 2-phenylethylamine only in the media without tyrosine added. In BHI added or not with tyrosine the tyrDC gene expression level differed considerably depending on the strains and the growth phase. In particular, the tyrDC gene expression was high during the exponential phase in rich medium for all the strains and subsequently decreased except for E. faecium FC12. Even if tyrDC presence is common among enterococci, this study underlines the extremely variable decarboxylating potential of strains belonging to the same species, suggesting strain-dependent implications in food safety.

  16. Characterization of arginine decarboxylase from Dianthus caryophyllus.

    Science.gov (United States)

    Ha, Byung Hak; Cho, Ki Joon; Choi, Yu Jin; Park, Ky Young; Kim, Kyung Hyun

    2004-04-01

    Arginine decarboxylase (ADC, EC 4.1.1.9) is a key enzyme in the biosynthesis of polyamines in higher plants, whereas ornithine decarboxylase represents the sole pathway of polyamine biosynthesis in animals. Previously, we characterized a genomic clone from Dianthus caryophyllus, in which the deduced polypeptide of ADC was 725 amino acids with a molecular mass of 78 kDa. In the present study, the ADC gene was subcloned into the pGEX4T1 expression vector in combination with glutathione S-transferase (GST). The fusion protein GST-ADC was water-soluble and thus was purified by sequential GSTrap-arginine affinity chromatography. A thrombin-mediated on-column cleavage reaction was employed to release free ADC from GST. Hiload superdex gel filtration FPLC was then used to obtain a highly purified ADC. The identity of the ADC was confirmed by immunoblot analysis, and its specific activity with respect to (14)C-arginine decarboxylation reaction was determined to be 0.9 CO(2) pkat mg(-1) protein. K(m) and V(max) of the reaction between ADC and the substrate were 0.077 +/- 0.001 mM and 6.0 +/- 0.6 pkat mg(-1) protein, respectively. ADC activity was reduced by 70% in the presence of 0.1 mM Cu(2+) or CO(2+), but was only marginally affected by Mg(2+), or Ca(2+) at the same concentration. Moreover, spermine at 1 mM significantly reduced its activity by 30%.

  17. L-DOPA decarboxylase mRNA expression is associated with tumor stage and size in head and neck squamous cell carcinoma: a retrospective cohort study

    Directory of Open Access Journals (Sweden)

    Geomela Panagiota-Aikaterini

    2012-10-01

    Full Text Available Abstract Background Head and neck squamous cell carcinoma (HNSCC represents one of the most commonly diagnosed malignancies worldwide. The DDC gene encodes L-DOPA decarboxylase, an enzyme catalyzing the decarboxylation of L-DOPA to dopamine. We have recently shown that DDC mRNA is a significant predictor of patients’ prognosis in colorectal adenocarcinoma and prostate cancer. The aim of the current study was to analyze the DDC mRNA expression in HNSCC patients. Methods 53 malignant tumors were resected from the larynx, pharynx, tongue, buccal mucosa, parotid glands, and nasal cavity, as well as from 34 adjacent non-cancerous tissues of HNSCC patients, and were homogenized. Total RNA was isolated and converted into first-strand cDNA. An ultrasensitive real-time PCR method based on the SYBR Green chemistry was used for DDC mRNA quantification in head and neck tissue specimens. Relative quantification was performed using the comparative Ct (2-ddCt method. Results DDC mRNA levels were lower in squamous cell carcinomas (SCCs of the larynx and tongue than in adjacent non-cancerous tissue specimens. Furthermore, low DDC mRNA expression was noticed in laryngeal and tongue tumors of advanced TNM stage or bigger size, compared to early-stage or smaller tumors, respectively. No statistically significant differences were observed between SCCs resected from pharynx, buccal mucosa, or nasal cavity, and their normal counterparts. Conclusion This is the first study examining the DDC mRNA expression in HNSCC. According to our results, DDC mRNA expression may constitute a potential prognostic biomarker in tongue and/or larynx SCCs, which principally represent the overwhelming majority of HNSCC cases.

  18. Immunocytochemical localization of glutamic acid decarboxylase (GAD) and substance P in neural areas mediating motion-induced emesis: Effects of vagal stimulation on GAD immunoreactivity

    Science.gov (United States)

    Damelio, F.; Gibbs, M. A.; Mehler, W. R.; Daunton, Nancy G.; Fox, Robert A.

    1991-01-01

    Immunocytochemical methods were employed to localize the neurotransmitter amino acid gamma-aminobutyric acid (GABA) by means of its biosynthetic enzyme glutamic acid decarboxylase (GAD) and the neuropeptide substance P in the area postrema (AP), area subpostrema (ASP), nucleus of the tractus solitarius (NTS), and gelatinous nucleus (GEL). In addition, electrical stimulation was applied to the night vagus nerve at the cervical level to assess the effects on GAD-immunoreactivity (GAR-IR). GAD-IR terminals and fibers were observed in the AP, ASP, NTS, and GEL. They showed pronounced density at the level of the ASP and gradual decrease towards the solitary complex. Nerve cells were not labelled in our preparations. Ultrastructural studies showed symmetric or asymmetric synaptic contracts between labelled terminals and non-immunoreactive dendrites, axons, or neurons. Some of the labelled terminals contained both clear- and dense-core vesicles. Our preliminary findings, after electrical stimulation of the vagus nerve, revealed a bilateral decrease of GAD-IR that was particularly evident at the level of the ASP. SP-immunoreactive (SP-IR) terminals and fibers showed varying densities in the AP, ASP, NTS, and GEL. In our preparations, the lateral sub-division of the NTS showed the greatest accumulation. The ASP showed medium density of immunoreactive varicosities and terminals and the AP and GEL displayed scattered varicose axon terminals. The electron microscopy revealed that all immunoreactive terminals contained clear-core vesicles which make symmetric or asymmetric synaptic contact with unlabelled dendrites. It is suggested that the GABAergic terminals might correspond to vagal afferent projections and that GAD/GABA and substance P might be co-localized in the same terminal allowing the possibility of a regulated release of the transmitters in relation to demands.

  19. Role of the NR2A/2B subunits of the N-methyl-D-aspartate receptor in glutamate-induced glutamic acid decarboxylase alteration in cortical GABAergic neurons in vitro.

    Science.gov (United States)

    Monnerie, H; Hsu, F-C; Coulter, D A; Le Roux, P D

    2010-12-29

    The vulnerability of brain neuronal cell subpopulations to neurologic insults varies greatly. Among cells that survive a pathological insult, for example ischemia or brain trauma, some may undergo morphological and/or biochemical changes that may compromise brain function. The present study is a follow-up of our previous studies that investigated the effect of glutamate-induced excitotoxicity on the GABA synthesizing enzyme glutamic acid decarboxylase (GAD65/67)'s expression in surviving DIV 11 cortical GABAergic neurons in vitro [Monnerie and Le Roux, (2007) Exp Neurol 205:367-382, (2008) Exp Neurol 213:145-153]. An N-methyl-D-aspartate receptor (NMDAR)-mediated decrease in GAD expression was found following glutamate exposure. Here we examined which NMDAR subtype(s) mediated the glutamate-induced change in GAD protein levels. Western blotting techniques on cortical neuron cultures showed that glutamate's effect on GAD proteins was not altered by NR2B-containing diheteromeric (NR1/NR2B) receptor blockade. By contrast, blockade of triheteromeric (NR1/NR2A/NR2B) receptors fully protected against a decrease in GAD protein levels following glutamate exposure. When receptor location on the postsynaptic membrane was examined, extrasynaptic NMDAR stimulation was observed to be sufficient to decrease GAD protein levels similar to that observed after glutamate bath application. Blocking diheteromeric receptors prevented glutamate's effect on GAD proteins after extrasynaptic NMDAR stimulation. Finally, NR2B subunit examination with site-specific antibodies demonstrated a glutamate-induced, calpain-mediated alteration in NR2B expression. These results suggest that glutamate-induced excitotoxic NMDAR stimulation in cultured GABAergic cortical neurons depends upon subunit composition and receptor location (synaptic vs. extrasynaptic) on the neuronal membrane. Biochemical alterations in surviving cortical GABAergic neurons in various disease states may contribute to the altered

  20. The influence of the cell free solution of lactic acid bacteria on tyramine production by food borne-pathogens in tyrosine decarboxylase broth.

    Science.gov (United States)

    Toy, Nurten; Özogul, Fatih; Özogul, Yesim

    2015-04-15

    The function of cell-free solutions (CFSs) of lactic acid bacteria (LAB) on tyramine and other biogenic amine production by different food borne-pathogens (FBPs) was investigated in tyrosine decarboxylase broth (TDB) using HPLC. Cell free solutions were prepared from four LAB strains. Two different concentrations which were 50% (5 ml CFS+5 ml medium/1:1) and 25% (2.5 ml CFS+7.5 ml medium/1:3) CFS and the control without CFS were prepared. Both concentration of CFS of Streptococcus thermophilus and 50% CFS of Pediococcus acidophilus inhibited tyramine production up to 98% by Salmonella paratyphi A. Tyramine production by Escherichia coli was also inhibited by 50% CFS of Lactococcus lactis subsp. lactis and 25% CFS of Leuconostoc lactis. subsp. cremoris. The inhibitor effect of 50% CFS of P. acidophilus was the highest on tyramine production (55%) by Listeria monocytogenes, following Lc. lactis subsp. lactis and Leuconostoc mesenteroides subsp. cremoris (20%) whilst 25% CFS of Leu. mes. subsp. cremoris and Lc. lactis subsp. lactis showed stimulator effects (160%). The stimulation effects of 50% CFS of S. thermophilus and Lc. lactis subsp. lactis were more than 70% by Staphylococcus aureus comparing to the control. CFS of LAB strains showed statistically inhibitor effect since lactic acid inhibited microbial growth, decreased pH quickly and reduced the formation of AMN and BAs. Consequently, in order to avoid the formation of high concentrations of biogenic amines in fermented food by bacteria, it is advisable to use CFS for food and food products.

  1. RAPID DETERMINA TION OF L—GLUTAMIC ACID WITH AN ENZYME REACTOR OFL—GLUTAMIC DECARBOXYLASE IMMOBILIZED ON ION EXCHANGE RESIN

    Institute of Scientific and Technical Information of China (English)

    WUGuoqi; LINGDaren; 等

    2001-01-01

    The preparation and characterization of an immobilized L-glutamic decarboxylase(GDC) were studied.This work is to develop a sensitive method for the determination of L-glutamate using a new biosensor,which consists of an enzyme column reactor of GDC immobilized on a novel ion exchange resin(carboxymethyl-copolymer of allyl dextran and N.N'-methylene-bisacrylamide CM-CADB) and ion analyzer coupled with a CO2 electrode.The conditions for the enzyme immobilization were optimized by the parameters:buffer composition and concentration,adsorption equilibration time,amount of enzyme,temperature,ionic strength and pH.The properties of the immobilized enzyme on CM-CADB were studied by investigating the initial ate of the enzyme reaction,the effect of various parameters on the immobilized GDC activity and its stability.An immobilized GDC enzyme column reactor matched with a flow injection system-ion analyzer coupled with CO2 electrode-data collection system made up the original form of the apparatus of biosensor for determining of L-glutamate acid.The limit of detection is 1.0×10-5M.The linearity response is in the range of 5×10-2-5×10-5M.The equation of linear regression of the calibration curve is y=43.3x+181.6(y is the milli-volt of electrical potential response,x is the logarithm of the concentration of the substrate of L-glutamate acid).The correlation coefficient equals 0.99.The coefficient of varioation equals 2.7%.

  2. Repeated morphine treatment alters polysialylated neural cell adhesion molecule, glutamate decarboxylase-67 expression and cell proliferation in the adult rat hippocampus.

    Science.gov (United States)

    Kahn, Laëtitia; Alonso, Gérard; Normand, Elisabeth; Manzoni, Olivier J

    2005-01-01

    Altered synaptic transmission and plasticity in brain areas involved in reward and learning are thought to underlie the long-lasting effects of addictive drugs. In support of this idea, opiates reduce neurogenesis [A.J. Eisch et al. (2000) Proceedings of the National Academy of Sciences USA, 97, 7579-7584] and enhance long-term potentiation in adult rodent hippocampus [J.M. Harrison et al. (2002) Journal of Neurophysiology, 87, 2464-2470], a key structure of learning and memory processes. Here we studied how repeated morphine treatment and withdrawal affect cell proliferation and neuronal phenotypes in the dentate gyrus-CA3 region of the adult rat hippocampus. Our data showed a strong reduction of cellular proliferation in morphine-dependent animals (54% of control) that was followed by a rebound increase after 1 week withdrawal and a return to normal after 2 weeks withdrawal. Morphine dependence was also associated with a drastic reduction in the expression levels of the polysialylated form of neural cell adhesion molecule (68% of control), an adhesion molecule expressed by newly generated neurons and involved in cell migration and structural plasticity. Polysialylated neural cell adhesion molecule levels quickly returned to normal following withdrawal. In morphine-dependent rats, we found a significant increase of glutamate decarboxylase-67 mRNA transcription (170% of control) in dentate gyrus granular cells which was followed by a marked rebound decrease after 1 week withdrawal and a return to normal after 4 weeks withdrawal. Together, the results show, for the first time, that, in addition to reducing cell proliferation and neurogenesis, chronic exposure to morphine dramatically alters neuronal phenotypes in the dentate gyrus-CA3 region of the adult rat hippocampus.

  3. C3-C4 intermediacy in grasses: organelle enrichment and distribution, glycine decarboxylase expression, and the rise of C2 photosynthesis.

    Science.gov (United States)

    Khoshravesh, Roxana; Stinson, Corey R; Stata, Matt; Busch, Florian A; Sage, Rowan F; Ludwig, Martha; Sage, Tammy L

    2016-05-01

    Photorespiratory glycine shuttling and decarboxylation in bundle sheath (BS) cells exhibited by C2 species is proposed to be the evolutionary bridge to C4 photosynthesis in eudicots. To evaluate this in grasses, we compare anatomy, cellular localization of glycine decarboxylase (GDC), and photosynthetic physiology of a suspected C2 grass, Homolepis aturensis, with these traits in known C2 grasses, Neurachne minor and Steinchisma hians, and C3 S laxum that is sister to S hians We also use publicly available genome and RNA-sequencing data to examine the evolution of GDC subunits and enhance our understanding of the evolution of BS-specific GDC expression in C2 and C4 grasses. Our results confirm the identity of H aturensis as a C2 species; GDC is confined predominantly to the organelle-enriched BS cells in H aturensis and S hians and to mestome sheath cells of N minor Phylogenetic analyses and data obtained from immunodetection of the P-subunit of GDC are consistent with the hypothesis that the BS dominant levels of GDC in C2 and C4 species are due to changes in expression of a single GLDP gene in M and BS cells. All BS mitochondria and peroxisomes and most chloroplasts in H aturensis and S hians are situated centripetally in a pattern identical to C2 eudicots. In S laxum, which has C3-like gas exchange patterns, mitochondria and peroxisomes are positioned centripetally as they are in S hians This subcellular phenotype, also present in eudicots, is posited to initiate a facilitation cascade leading to C2 and C4 photosynthesis.

  4. Cloning and expression analysis of pyruvate decarboxylase gene in Salvia miltiorrhiza%白花丹参丙酮酸脱羧酶基因的克隆和表达分析

    Institute of Scientific and Technical Information of China (English)

    史仁玖; 常正尧; 王健美; 王德才

    2013-01-01

    Objective To obtain the fulllength of Salvia miltiorrhiza pyruvate decarboxylase (SmPDC) gene, to analyze the expression differences in various tissues of S. miltiorrhiza after anaerobic stress treatment. Methods The fulllength of SmPDC gene was isolated through sequencing cDNA library, and semi-quantitative RT-PCR was used to detect the gene expression levels. Results The fulllength of SmPDC cDNA has an open reading frame of 2 190 bp. The deduced amino acid sequence of SmPDC has 605 amino acid residues which form a 6.485×104 polypeptide with a calculated pI of 5.49. Semi-quantitative RT-PCR indicated that SmPDC gene was expressed at a high level in root, followed by stem and leaf of 5. miltiorrhiza. Anaerobic stress could induce the expression of SmPDC gene and the expression was increased with the stress time elongating. Conclusion SmPDC is a new member of the PDC family and plays an important role in anaerobic respiration pathway.%目的 获得白花丹参丙酮酸脱羧酶(SmPDC)全长基因,分析该基因在白花丹参不同组织部位,以及缺氧胁迫处理后的该基因表达差异.方法 利用cDNA文库筛选获得SmPDC基因全长,利用半定量RT-PCR,分析SmPDC基因在白花丹参不同部位的表达情况,及缺氧处理条件下的表达情况.结果 获得的SmPDC基因由2 190个核苷酸组成,编码605个氨基酸,蛋白相对分子质量药6.485×104,等电点pI 5.49;半定量RT-PCR检测,该基因在丹参的根中表达量最高,其次是茎和叶;缺氧胁迫处理会诱导该基因的表达,随胁迫时间延长表达量逐渐增加.结论 白花丹参SmPDC基因是PDC家族新成员,其功能与植物耐缺氧代谢途径有关.

  5. Role of Dopaminergic D2 Receptors in the Regulation of Glutamic Acid Decarboxylase Messenger RNA in the Striatum of the Rat.

    Science.gov (United States)

    Caboche, Jocelyne; Vernier, Philippe; Rogard, Monique; Julien, Jean-François; Mallet, Jacques; Besson, Marie-Jo

    1992-01-01

    Levels of messenger RNA (mRNA) encoding glutamic acid decarboxylase (GAD) and preproenkephalin (PPE) were measured by Northern blot and in situ hybridization analyses in the striatum of the rat, after chronic injections of two neuroleptics, sulpiride and haloperidol. The Northern blot analysis showed that the chronic injection of sulpiride at high doses (80 mg/kg, twice a day, 14 days) increased striatal GAD and PPE mRNA levels by 120% and 78% respectively, when compared to vehicle-injected rats. Haloperidol injections at relatively low doses (1 mg/kg, once a day, 14 days) produced parallel increases in GAD (40%) and PPE (52%) mRNA levels. After in situ hybridization densitometric measurements were performed on autoradiograms from rats treated with sulpiride, haloperidol or vehicle. The distribution of GAD and PPE mRNA signals in control rats was homogeneous along the rostrocaudal extension of the striatum. A similar increase was found along this axis after sulpiride (20%) and haloperidol (30%) treatments. The cellular observation of hybridization signals showed that grain density for GAD mRNA was increased in a majority of striatal cells after both treatments. By contrast, the PPE mRNA hybridization signal only increased in a subpopulation of neurons. The effects of such treatments were also analysed by measuring GAD activity in the striatum and in its output structures, the globus pallidus and the substantia nigra. After the administration of sulpiride, GAD activity was not modified in the striatum but increased in the globus pallidus (by 17%). After haloperidol treatment, GAD activity was increased in the globus pallidus (20%) and the substantia nigra (17%). It is concluded that the interruption of dopaminergic transmission, more precisely the D2 receptor blockade, promotes in striatopallidal neurons an increase in GAD mRNA accompanied by an increase in GAD activity and PPE mRNA. A possible regulation of GAD mRNA and GAD activity in striatonigral neurons is also

  6. Progressive loss of glutamic acid decarboxylase, parvalbumin, and calbindin D28K immunoreactive neurons in the cerebral cortex and hippocampus of adult rat with experimental hydrocephalus.

    Science.gov (United States)

    Tashiro, Y; Chakrabortty, S; Drake, J M; Hattori, T

    1997-02-01

    The authors investigated functional neuronal changes in experimental hydrocephalus using immunohistochemical techniques for glutamic acid decarboxylase (GAD) and two neuronal calcium-binding proteins: parvalbumin (PV) and calbindin D28K (CaBP). Hydrocephalus was induced in 16 adult Wistar rats by intracisternal injection of a kaolin solution, which was confirmed microscopically via atlantooccipital dural puncture. Four control rats received the same volume of sterile saline. Immunohistochemical staining for GAD, PV, and CaBP, and Nissl staining were performed at 1, 2, 3, and 4 weeks after the injection. Hydrocephalus occurred in 90% of kaolin-injected animals with various degrees of ventricular dilation. In the cerebral cortex, GAD-, PV-, and CaBP-immunoreactive (IR) interneurons initially lost their stained processes together with a concomitant loss of homogeneous neuropil staining, followed by the reduction of their total number. With progressive ventricular dilation, GAD- and PV-IR axon terminals on the cortical pyramidal cells disappeared, whereas the number of CaBP-IR pyramidal cells decreased, and ultimately in the most severe cases of hydrocephalus, GAD, PV, and CaBP immunoreactivity were almost entirely diminished. In the hippocampus, GAD-, PV-, and CaBP-IR interneurons demonstrated a reduction of their processes and terminals surrounding the pyramidal cells, with secondary reduction of CaBP-IR pyramidal and granular cells. On the other hand, Nissl staining revealed almost no morphological changes induced by ischemia or neuronal degeneration even in the most severe cases of hydrocephalus. Hydrocephalus results in the progressive functional impairment of GAD-, PV-, and CaBP-IR neuronal systems in the cerebral cortex and hippocampus, often before there is evidence of morphological injury. The initial injury of cortical and hippocampal interneurons suggests that the functional deafferentation from intrinsic projection fibers may be the initial neuronal event

  7. The novel R347g pathogenic mutation of aromatic amino acid decarboxylase provides additional molecular insights into enzyme catalysis and deficiency.

    Science.gov (United States)

    Montioli, Riccardo; Paiardini, Alessandro; Kurian, Manju A; Dindo, Mirco; Rossignoli, Giada; Heales, Simon J R; Pope, Simon; Voltattorni, Carla Borri; Bertoldi, Mariarita

    2016-06-01

    We report here a clinical case of a patient with a novel mutation (Arg347→Gly) in the gene encoding aromatic amino acid decarboxylase (AADC) that is associated with AADC deficiency. The variant R347G in the purified recombinant form exhibits, similarly to the pathogenic mutation R347Q previously studied, a 475-fold drop of kcat compared to the wild-type enzyme. In attempting to unravel the reason(s) for this catalytic defect, we have carried out bioinformatics analyses of the crystal structure of AADC-carbidopa complex with the modelled catalytic loop (residues 328-339). Arg347 appears to interact with Phe103, as well as with both Leu333 and Asp345. We have then prepared and characterized the artificial F103L, R347K and D345A mutants. F103L, D345A and R347K exhibit about 13-, 97-, and 345-fold kcat decrease compared to the wild-type AADC, respectively. However, unlike F103L, the R347G, R347K and R347Q mutants as well as the D345A variant appear to be more defective in catalysis than in protein folding. Moreover, the latter mutants, unlike the wild-type protein and the F103L variant, share a peculiar binding mode of dopa methyl ester consisting of formation of a quinonoid intermediate. This finding strongly suggests that their catalytic defects are mainly due to a misplacement of the substrate at the active site. Taken together, our results highlight the importance of the Arg347-Leu333-Asp345 hydrogen-bonds network in the catalysis of AADC and reveal the molecular basis for the pathogenicity of the variants R347. Following the above results, a therapeutic treatment for patients bearing the mutation R347G is proposed.

  8. Evolution of Substrate Specificity within a Diverse Family of [beta/alpha]-Barrel-fold Basic Amino Acid Decarboxylases X-ray Structure Determination of Enzymes with Specificity for L-Arginine and Carboxynorspermidine

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Xiaoyi; Lee, Jeongmi; Michael, Anthony J.; Tomchick, Diana R.; Goldsmith, Elizabeth J.; Phillips, Margaret A. (Sungkyunkwan); (UTSMC)

    2010-08-26

    Pyridoxal 5{prime}-phosphate (PLP)-dependent basic amino acid decarboxylases from the {beta}/{alpha}-barrel-fold class (group IV) exist in most organisms and catalyze the decarboxylation of diverse substrates, essential for polyamine and lysine biosynthesis. Herein we describe the first x-ray structure determination of bacterial biosynthetic arginine decarboxylase (ADC) and carboxynorspermidine decarboxylase (CANSDC) to 2.3- and 2.0-{angstrom} resolution, solved as product complexes with agmatine and norspermidine. Despite low overall sequence identity, the monomeric and dimeric structures are similar to other enzymes in the family, with the active sites formed between the {beta}/{alpha}-barrel domain of one subunit and the {beta}-barrel of the other. ADC contains both a unique interdomain insertion (4-helical bundle) and a C-terminal extension (3-helical bundle) and it packs as a tetramer in the asymmetric unit with the insertions forming part of the dimer and tetramer interfaces. Analytical ultracentrifugation studies confirmed that the ADC solution structure is a tetramer. Specificity for different basic amino acids appears to arise primarily from changes in the position of, and amino acid replacements in, a helix in the {beta}-barrel domain we refer to as the 'specificity helix.' Additionally, in CANSDC a key acidic residue that interacts with the distal amino group of other substrates is replaced by Leu{sup 314}, which interacts with the aliphatic portion of norspermidine. Neither product, agmatine in ADC nor norspermidine in CANSDC, form a Schiff base to pyridoxal 5{prime}-phosphate, suggesting that the product complexes may promote product release by slowing the back reaction. These studies provide insight into the structural basis for the evolution of novel function within a common structural-fold.

  9. Change of glutamic acid decarboxylase antibody and protein tyrosine phosphatase antibody in Chinese patients with acute-onset type 1 diabetes mellitus

    Institute of Scientific and Technical Information of China (English)

    CHAO Chen; HUANG Gan; LI Xia; YANG Lin; LIN Jian; JIN Ping; LUO Shuo-ming

    2013-01-01

    Background Glutamic acid decarboxylase antibody (GADA) and protein tyrosine phosphatase antibody (IA-2A) are two major autoantibodies,which exert important roles in the process of type 1 diabetes mellitus (T1D).Our study aimed to investigate the changes in positivity and titers of GADA and IA-2A during the course of Chinese acute-onset T1D patients and their relationships with clinical features.Methods Two hundreds and forty-seven Chinese newly diagnosed acute-onset T1D patients were consecutively recruited.GADA and IA-2A were detected at the time of diagnosis,one year later,3-5 years later after diagnosis during the follow-up; all the clinical data were recorded and analyzed as well.Results During the course of acute-onset T1D,the majority of patients remained stable for GADA or IA-2A,however,a few patients changed from positivity to negativity and fewer patients converted from negativity to positivity.The prevalence of GADA was 56.3% at diagnosis,decreasing to 50.5% one year later,and 43.3% 3-5 years later while the corresponding prevalence of IA-2A were 32.8%,31.0% and 23.3%,respectively.The median GADA titers were 0.0825 at diagnosis,declining to 0.0585 one year later and 0.0383 3-5 years later (P <0.001),while the corresponding median titers were 0.0016,0.0010,0.0014 for IA-2A,respectively.Fasting C-peptide (FCP) and postprandial C-peptide 2 hours (PCP2h)levels of GADA or IA-2A negativity persistence patients were higher than those of positivity persistence and negativity conversion patients (P <0.05) which indicated GADA or IA-2A negativity persistence T1D patients had a less loss of β cell function.Conclusion Our data suggest that repeated detection of GADA and IA-2A are necessary for differential diagnosis of autoimmune diabetes and the indirect prediction of the β cell function in Chinese patients.

  10. Cloning and Prokaryotic Expressing of Glutamate Decarboxylase Gene from Lactobacillus plantarum%植物乳杆菌谷氨酸脱羧酶基因的克隆及原核表达

    Institute of Scientific and Technical Information of China (English)

    时粲; 刘昭明; 黎娅; 易弋; 伍时华

    2015-01-01

    Based on the sequence of Lactobacillus plantarum WCFS1 published in GenBank, primers were designed and the glutamate decarboxylase encoding gene gadB from L. plantarum QL-14 was amplified by PCR technology. Then the target gene was expressed in Escherichia coli BL21 through fusion expression vector pGEX-4T-3, and the expression condition was optimized and target protein was purified. The results showed that the ORF of gadB gene was 1 407 bp and encoded 469 amino acids, 99.6% homology with L. plantarum WCFS1. After optimizing the inducing condition, the molecular weight and pI of purified GAD protein reached to 53.6 ku and 5.58 respectively, with an activity of 9.9 U/mg.%根据GenBank中植物乳杆菌(Lactobacillus plantarum)基因组序列设计引物,利用PCR技术扩增了植物乳杆菌QL-14的谷氨酸脱羧酶编码基因gadB,克隆至表达载体pGEX-4T-3,转化大肠杆菌(Es-cherichia coli)后进行原核表达,对表达条件进行了优化并对表达蛋白质进了纯化。结果表明,扩增目的gadB基因的开放阅读框(ORF)全长1407 bp,编码469个氨基酸,氨基酸序列与植物乳杆菌WCFS1同源性为99.6%。通过优化诱导表达条件,得到纯化蛋白质GAD大小为53.6 ku,等电点为5.58,比活力为9.9 U/mg。

  11. Pantothenic acid biosynthesis in zymomonas

    Energy Technology Data Exchange (ETDEWEB)

    Tao, Luan; Tomb, Jean-Francois; Viitanen, Paul V.

    2014-07-01

    Zymomonas is unable to synthesize pantothenic acid and requires this essential vitamin in growth medium. Zymomonas strains transformed with an operon for expression of 2-dehydropantoate reductase and aspartate 1-decarboxylase were able to grow in medium lacking pantothenic acid. These strains may be used for ethanol production without pantothenic acid supplementation in seed culture and fermentation media.

  12. Genetic manipulation of the γ-aminobutyric acid (GABA) shunt in rice: overexpression of truncated glutamate decarboxylase (GAD2) and knockdown of γ-aminobutyric acid transaminase (GABA-T) lead to sustained and high levels of GABA accumulation in rice kernels.

    Science.gov (United States)

    Shimajiri, Yasuka; Oonishi, Takayuki; Ozaki, Kae; Kainou, Kumiko; Akama, Kazuhito

    2013-06-01

    Gamma-aminobutyric acid (GABA) is a non-protein amino acid commonly present in all organisms. Because cellular levels of GABA in plants are mainly regulated by synthesis (glutamate decarboxylase, GAD) and catabolism (GABA-transaminase, GABA-T), we attempted seed-specific manipulation of the GABA shunt to achieve stable GABA accumulation in rice. A truncated GAD2 sequence, one of five GAD genes, controlled by the glutelin (GluB-1) or rice embryo globulin promoters (REG) and GABA-T-based trigger sequences in RNA interference (RNAi) cassettes controlled by one of these promoters as well, was introduced into rice (cv. Koshihikari) to establish stable transgenic lines under herbicide selection using pyriminobac. T₁ and T₂ generations of rice lines displayed high GABA concentrations (2-100 mg/100 g grain). In analyses of two selected lines from the T₃ generation, there was a strong correlation between GABA level and the expression of truncated GAD2, whereas the inhibitory effect of GABA-T expression was relatively weak. In these two lines both with two T-DNA copies, their starch, amylose, and protein levels were slightly lower than non-transformed cv. Koshihikari. Free amino acid analysis of mature kernels of these lines demonstrated elevated levels of GABA (75-350 mg/100 g polished rice) and also high levels of several amino acids, such as Ala, Ser, and Val. Because these lines of seeds could sustain their GABA content after harvest (up to 6 months), the strategy in this study could lead to the accumulation GABA and for these to be sustained in the edible parts.

  13. Vector-mediated chromosomal integration of the glutamate decarboxylase gene in streptococcus thermophilus

    Science.gov (United States)

    The integrative vector pINTRS was used to transfer glutamate decarboxylase (GAD) activity to Streptococcus thermophilus ST128, thus allowing for the production of '-aminobutyric acid (GABA). In pINTRS, the gene encoding glutamate decarboxylase, gadB, was flanked by DNA fragments homologous to a S. ...

  14. A standard numbering scheme for thiamine diphosphate-dependent decarboxylases

    Directory of Open Access Journals (Sweden)

    Vogel Constantin

    2012-11-01

    Full Text Available Abstract Background Standard numbering schemes for families of homologous proteins allow for the unambiguous identification of functionally and structurally relevant residues, to communicate results on mutations, and to systematically analyse sequence-function relationships in protein families. Standard numbering schemes have been successfully implemented for several protein families, including lactamases and antibodies, whereas a numbering scheme for the structural family of thiamine-diphosphate (ThDP -dependent decarboxylases, a large subfamily of the class of ThDP-dependent enzymes encompassing pyruvate-, benzoylformate-, 2-oxo acid-, indolpyruvate- and phenylpyruvate decarboxylases, benzaldehyde lyase, acetohydroxyacid synthases and 2-succinyl-5-enolpyruvyl-6-hydroxy-3-cyclohexadiene-1-carboxylate synthase (MenD is still missing. Despite a high structural similarity between the members of the ThDP-dependent decarboxylases, their sequences are diverse and make a pairwise sequence comparison of protein family members difficult. Results We developed and validated a standard numbering scheme for the family of ThDP-dependent decarboxylases. A profile hidden Markov model (HMM was created using a set of representative sequences from the family of ThDP-dependent decarboxylases. The pyruvate decarboxylase from S. cerevisiae (PDB: 2VK8 was chosen as a reference because it is a well characterized enzyme. The crystal structure with the PDB identifier 2VK8 encompasses the structure of the ScPDC mutant E477Q, the cofactors ThDP and Mg2+ as well as the substrate analogue (2S-2-hydroxypropanoic acid. The absolute numbering of this reference sequence was transferred to all members of the ThDP-dependent decarboxylase protein family. Subsequently, the numbering scheme was integrated into the already established Thiamine-diphosphate dependent Enzyme Engineering Database (TEED and was used to systematically analyze functionally and structurally relevant

  15. Subcellular localization of the voltage-gated potassium channels Kv3.1b and Kv3.3 in the cerebellar dentate nucleus of glutamic acid decarboxylase 67-green fluorescent protein transgenic mice.

    Science.gov (United States)

    Alonso-Espinaco, V; Elezgarai, I; Díez-García, J; Puente, N; Knöpfel, T; Grandes, P

    2008-09-09

    Deep cerebellar dentate nuclei are in a key position to control motor planning as a result of an integration of cerebropontine inputs and hemispheric Purkinje neurons signals, and their influence through synaptic outputs onto extracerebellar hubs. GABAergic dentate neurons exhibit broader action potentials and slower afterhyperpolarization than non-GABAergic (presumably glutamatergic) neurons. Specific potassium channels may be involved in these distinct firing profiles, particularly, Kv3.1 and Kv3.3 subunits which rapidly activate at relatively positive potentials to support the generation of fast action potentials. To investigate the subcellular localization of Kv3.1b and Kv3.3 in GAD- and GAD+ dentate neurons of glutamic acid decarboxylase 67-green fluorescent protein (GAD67-GFP) knock-in mice a preembedding immunocytochemical method for electron microscopy was used. Kv3.1b and Kv3.3 were in membranes of cell somata, dendrites, axons and synaptic terminals of both GAD- and GAD+ dentate neurons. The vast majority of GAD- somatodendritic membrane segments domains labeled for Kv3.1b and Kv3.3 (96.1% and 84.7%, respectively) whereas 56.2% and 69.8% of GAD- axonal membrane segments were immunopositive for these subunits. Furthermore, density of Kv3.1b immunoparticles was much higher in GAD- somatodendritic than axonal domains. As to GAD+ neurons, only 70.6% and 50% of somatodendritic membrane segments, and 53.3% and 59.5% of axonal membranes exhibited Kv3.1b and Kv3.3 labeling, respectively. In contrast to GAD- cells, GAD+ cells exhibited a higher density labeling for both Kv3 subunits at their axonal than at their somatodendritic membranes. Taken together, Kv3.1b and Kv3.3 potassium subunits are expressed in both GAD- and GAD+ cells, albeit at different densities and distribution. They likely contribute to the distinct biophysical properties of both GAD- and GAD+ neurons in the dentate nucleus.

  16. Effects of down-regulating ornithine decarboxylase upon putrescine-associated metabolism and growth in Nicotiana tabacum L.

    Science.gov (United States)

    Dalton, Heidi L; Blomstedt, Cecilia K; Neale, Alan D; Gleadow, Ros; DeBoer, Kathleen D; Hamill, John D

    2016-05-01

    Transgenic plants of Nicotiana tabacum L. homozygous for an RNAi construct designed to silence ornithine decarboxylase (ODC) had significantly lower concentrations of nicotine and nornicotine, but significantly higher concentrations of anatabine, compared with vector-only controls. Silencing of ODC also led to significantly reduced concentrations of polyamines (putrescine, spermidine and spermine), tyramine and phenolamides (caffeoylputrescine and dicaffeoylspermidine) with concomitant increases in concentrations of amino acids ornithine, arginine, aspartate, glutamate and glutamine. Root transcript levels of S-adenosyl methionine decarboxylase, S-adenosyl methionine synthase and spermidine synthase (polyamine synthesis enzymes) were reduced compared with vector controls, whilst transcript levels of arginine decarboxylase (putrescine synthesis), putrescine methyltransferase (nicotine production) and multi-drug and toxic compound extrusion (alkaloid transport) proteins were elevated. In contrast, expression of two other key proteins required for alkaloid synthesis, quinolinic acid phosphoribosyltransferase (nicotinic acid production) and a PIP-family oxidoreductase (nicotinic acid condensation reactions), were diminished in roots of odc-RNAi plants relative to vector-only controls. Transcriptional and biochemical differences associated with polyamine and alkaloid metabolism were exacerbated in odc-RNAi plants in response to different forms of shoot damage. In general, apex removal had a greater effect than leaf wounding alone, with a combination of these injury treatments producing synergistic responses in some cases. Reduced expression of ODC appeared to have negative effects upon plant growth and vigour with some leaves of odc-RNAi lines being brittle and bleached compared with vector-only controls. Together, results of this study demonstrate that ornithine decarboxylase has important roles in facilitating both primary and secondary metabolism in Nicotiana.

  17. Molecular cloning and functional identification of a plant ornithine decarboxylase cDNA.

    Science.gov (United States)

    Michael, A J; Furze, J M; Rhodes, M J; Burtin, D

    1996-02-15

    A cDNA for a plant ornithine decarboxylase (ODC), a key enzyme in putrescine and polyamine biosynthesis, has been isolated from root cultures of the solanaceous plant Datura stramonium. Reverse transcription-PCR employing degenerate oligonucleotide primers representing conserved motifs from other eukaryotic ODCs was used to isolate the cDNA. The longest open reading frame potentially encodes a peptide of 431 amino acids and exhibits similarity to other eukaryotic ODCs, prokaryotic and eukaryotic arginine decarboxylases (ADCs), prokaryotic meso-diaminopimelate decarboxylases and the product of the tabA gene of Pseudomonas syringae cv. tabaci. Residues involved at the active site of the mouse ODC are conserved in the plant enzyme. The plant ODC does not possess the C-terminal extension found in the mammalian enzyme, implicated in rapid turnover of the protein, suggesting that the plant ODC may have a longer half-life. Expression of the plant ODC in Escherichia coli and demonstration of ODC activity confirmed that the cDNA encodes an active ODC enzyme. This is the first description of the primary structure of a eukaryotic ODC isolated from an organism where the alternative ADC routine to putrescine is present.

  18. Cloning and expression analysis of a lysine decarboxylase gene in Sophora alopecuroides%苦豆子赖氨酸脱羧酶基因克隆与表达分析

    Institute of Scientific and Technical Information of China (English)

    杨毅; 陆姗姗; 刘萍; 田蕾

    2016-01-01

    赖氨酸脱羧酶(lysine decarboxylase,LDC)基因是苦豆子中氧化苦参碱(oxymatrine,OMA)生物合成的第一个关键酶基因。根据近缘物种苦参的赖氨酸脱羧酶基因设计特异引物,同源克隆法克隆了苦豆子赖氨酸脱羧酶基因的蛋白质编码区序列,全长1368 bp,命名为 Sa-LDC,GenBank 登录号为 KM249871。生物信息学分析表明 Sa-LDC 编码区序列无内含子,与苦参和狗苦参的 LDC 序列一致性均达到97%;属于Ⅲ型5-磷酸吡哆醛依赖酶[typeⅢ pyridoxal 5-phosphate (PLP)-dependent enzymes,PLPDE-Ⅲ]超基因家族,功能活跃。Sa-LDC 编码455个氨基酸残基,其编码的肽链相对分子质量49.14 kD,理论等电点5.63,无信号肽和跨膜结构;在其氨基酸序列中具有产喹诺里西啶生物碱的特征性保守位点 Phe340;系统进化树将苦豆子与其他产喹诺里西啶类生物碱的植物聚为一类。qPCR 和 HPLC 检测显示,苦豆子赖氨酸脱羧酶基因的表达和氧化苦参碱的积累均受干旱胁迫的影响,且基因的表达量与氧化苦参碱的积累呈正相关关系。%In the biochemical metabolic processes of Sophora alopecuroides ,a lysine decarboxylase (LDC)gene is one of the key enzyme genes involved in the process of Oxymatrine biosynthesis.In the present study,the full length of the LDC coding sequence in S .alopecuroides was cloned using a pair of specific primers designed based on the LDC sequence of Sophora flavescens and was named Sa-LDC (gene bank accession number:KM249871).Sa-LDC belongs to the Type Ⅲ Pyridoxal 5-phosphate (PLP)-Dependent enzyme supergene fami-ly,is comprised of a 1368 bps open reading frame (ORF)without intron,and has 97% identity with the LDC of Echinosophora koreensis and S .flavescens in GeneBank.Its nucleotide sequence encodes 455 amino acid resi-dues whose putative protein had a relative molecular mass of 49.14 kD and the theoretical isoelectric point

  19. Altered subcellular localization of ornithine decarboxylase in Alzheimer's disease brain

    DEFF Research Database (Denmark)

    Nilsson, Tatjana; Bogdanovic, Nenad; Volkman, Inga

    2006-01-01

    The amyloid precursor protein can through ligand-mimicking induce expression of ornithine decarboxylase (ODC), the initial and rate-limiting enzyme in polyamine biosynthesis. We report here the regional distribution and cellular localization of ODC immunoreactivity in Alzheimer's disease (AD...

  20. Characterization of a second ornithine decarboxylase isolated from Morganella morganii.

    Science.gov (United States)

    De Las Rivas, Blanca; González, Ramón; Landete, José María; Muñoz, Rosario

    2008-03-01

    The genes involved in the putrescine formation by Morganella morganii were investigated because putrescine is an indicator of food process deterioration. We report here on the existence of a new gene for ornithine decarboxylase (ODC) in M. morganii. The sequenced 5,311-bp DNA region showed the presence of four complete and one partial open reading frame. Putative functions have been assigned to several gene products by sequence comparison with the proteins included in the databases. The third open reading frame (speC) encoded a 722-amino acid protein showing 70.9% identity to the M. morganii ODC previously characterized (SpeF). The speC gene has been expressed in Escherichia coli, resulting in ODC activity. The presence of a functional promoter (PspeC) located upstream of speC has been demonstrated. Quantitative real-time reverse transcription PCR assay was used to quantify expression of both M. morganii ODC-encoding genes, speC and speF, under different growth conditions. This assay allows us to identify SpeF as the inducible M. morganii ODC, since it was highly expressed in the presence of ornithine.

  1. 粘质沙雷氏菌α-乙酰乳酸脱羧酶基因的体外表达%Expression of Serratia marcescens α-Acetolactate Decarboxylase Gene in Escherichia coli and Pichia pastoris

    Institute of Scientific and Technical Information of China (English)

    王亚平; 周荣华; 饶犇; 马立新

    2013-01-01

    根据GenBank中α-乙酰乳酸脱羧酶的基因序列(slaA)设计引物,以粘质沙雷氏菌(Serratia marcescens)HU1基因组DNA为模板通过PCR扩增得到了目标基因,全长为780 bp.将该基因分别连接到大肠杆菌表达载体pET30a和毕赤酵母表达栽体pPICZαA上,构建表达质粒pET30a-slaA和pPICZαA-slaA,并在对应的宿主中进行了表达.结果表明,大肠杆菌和毕赤酵母的表达产物的最适温度和pH均分别为40℃和7,两者在不同pH下的稳定性也相似,只不过毕赤酵母的表达产物的热稳定性要略强于大肠杆菌的表达产物.%Serratia marcescens α-acetolactate decarboxylase gene in Escherichia coli and Pichia pastoris,repectively.Primers of α-acetolactate decarboxylase gene (slaA) were designed according to the gene sequence in GeneBank; and target gene was obtained by PCR amplification using S.marcescens MG1 genomic DNA as template,which was 780 bp.Then slaA gene was inserted into pET-30a,expression vector of E.coli,and pPICZαA,expression vector of P.pastoris,resulting in plasmids pET30a-slaA and pPICZoA-slaA.The two expression vectors were introduced into the corresponding hosts and the gene was successfully expressed.The results showed that the optimum temperature and pH of the enzyme produced by E.coli and P.pastoris were both about 40 ℃ and 7,respectively.The stability of the enzyme at different pH from E.coli and P.pastoris was also similar.However,the thermal stability of the enzyme produced by P.pastoris was slightly stronger than that from E.coii.

  2. Expressing yeast SAMdc gene confers broad changes in gene expression and alters fatty acid composition in tomato fruit.

    Science.gov (United States)

    Kolotilin, Igor; Koltai, Hinanit; Bar-Or, Carmiya; Chen, Lea; Nahon, Sahadia; Shlomo, Haviva; Levin, Ilan; Reuveni, Moshe

    2011-07-01

    Tomato (Solanum lycopersicum) fruits expressing a yeast S-adenosyl methionine decarboxylase (ySAMdc) gene under control of a ripening-induced promoter show altered phytonutrient content and broad changes in gene expression. Genome-wide transcriptional alterations in pericarp tissues of the ySAMdc-expressing fruits are shown. Consistent with the ySAMdc expression pattern from the ripening-induced promoter, very minor transcriptional alterations were detected at the mature green developmental stage. At the breaker and red stages, altered levels of numerous transcripts were observed with a general tendency toward upregulation in the transgenic fruits. Ontological analysis of up- and downregulated transcript groups revealed various affected metabolic processes, mainly carbohydrate and amino acid metabolism, and protein synthesis, which appeared to be intensified in the ripening transgenic fruits. Other functional ontological categories of altered transcripts represented signal transduction, transcription regulation, RNA processing, molecular transport and stress response, as well as metabolism of lipids, glycans, xenobiotics, energy, cofactors and vitamins. In addition, transcript levels of genes encoding structural enzymes for several biosynthetic pathways showed strong correlations to levels of specific metabolites that displayed altered levels in transgenic fruits. Increased transcript levels of fatty acid biosynthesis enzymes were accompanied by a change in the fatty acid profile of transgenic fruits, most notably increasing ω-3 fatty acids at the expense of other lipids. Thus, SAMdc is a prime target in manipulating the nutritional value of tomato fruits. Combined with analyses of selected metabolites in the overripe fruits, a model of enhanced homeostasis of the pericarp tissue in the polyamine-accumulating tomatoes is proposed.

  3. Characterization of the Entamoeba histolytica ornithine decarboxylase-like enzyme.

    Directory of Open Access Journals (Sweden)

    Anupam Jhingran

    Full Text Available BACKGROUND: The polyamines putrescine, spermidine, and spermine are organic cations that are required for cell growth and differentiation. Ornithine decarboxylase (ODC, the first and rate-limiting enzyme in the polyamine biosynthetic pathway, is a highly regulated enzyme. METHODOLOGY AND RESULTS: To use this enzyme as a potential drug target, the gene encoding putative ornithine decarboxylase (ODC-like sequence was cloned from Entamoeba histolytica, a protozoan parasite causing amoebiasis. DNA sequence analysis revealed an open reading frame (ORF of approximately 1,242 bp encoding a putative protein of 413 amino acids with a calculated molecular mass of 46 kDa and a predicted isoelectric point of 5.61. The E. histolytica putative ODC-like sequence has 33% sequence identity with human ODC and 36% identity with the Datura stramonium ODC. The ORF is a single-copy gene located on a 1.9-Mb chromosome. The recombinant putative ODC protein (48 kDa from E. histolytica was heterologously expressed in Escherichia coli. Antiserum against recombinant putative ODC protein detected a band of anticipated size approximately 46 kDa in E. histolytica whole-cell lysate. Difluoromethylornithine (DFMO, an enzyme-activated irreversible inhibitor of ODC, had no effect on the recombinant putative ODC from E. histolytica. Comparative modeling of the three-dimensional structure of E. histolytica putative ODC shows that the putative binding site for DFMO is disrupted by the substitution of three amino acids-aspartate-332, aspartate-361, and tyrosine-323-by histidine-296, phenylalanine-305, and asparagine-334, through which this inhibitor interacts with the protein. Amino acid changes in the pocket of the E. histolytica enzyme resulted in low substrate specificity for ornithine. It is possible that the enzyme has evolved a novel substrate specificity. CONCLUSION: To our knowledge this is the first report on the molecular characterization of putative ODC-like sequence from

  4. Differential Regulation of Glutamic Acid Decarboxylase Gene Expression after Extinction of a Recent Memory vs. Intermediate Memory

    Science.gov (United States)

    Sangha, Susan; Ilenseer, Jasmin; Sosulina, Ludmila; Lesting, Jorg; Pape, Hans-Christian

    2012-01-01

    Extinction reduces fear to stimuli that were once associated with an aversive event by no longer coupling the stimulus with the aversive event. Extinction learning is supported by a network comprising the amygdala, hippocampus, and prefrontal cortex. Previous studies implicate a critical role of GABA in extinction learning, specifically the GAD65…

  5. Crystal Structure and Substrate Specificity of Drosophila 3,4-Dihydroxyphenylalanine Decarboxylase

    Energy Technology Data Exchange (ETDEWEB)

    Han, Q.; Ding, H; Robinson, H; Christensen, B; Li, J

    2010-01-01

    3,4-Dihydroxyphenylalanine decarboxylase (DDC), also known as aromatic L-amino acid decarboxylase, catalyzes the decarboxylation of a number of aromatic L-amino acids. Physiologically, DDC is responsible for the production of dopamine and serotonin through the decarboxylation of 3,4-dihydroxyphenylalanine and 5-hydroxytryptophan, respectively. In insects, both dopamine and serotonin serve as classical neurotransmitters, neuromodulators, or neurohormones, and dopamine is also involved in insect cuticle formation, eggshell hardening, and immune responses. In this study, we expressed a typical DDC enzyme from Drosophila melanogaster, critically analyzed its substrate specificity and biochemical properties, determined its crystal structure at 1.75 Angstrom resolution, and evaluated the roles residues T82 and H192 play in substrate binding and enzyme catalysis through site-directed mutagenesis of the enzyme. Our results establish that this DDC functions exclusively on the production of dopamine and serotonin, with no activity to tyrosine or tryptophan and catalyzes the formation of serotonin more efficiently than dopamine. The crystal structure of Drosophila DDC and the site-directed mutagenesis study of the enzyme demonstrate that T82 is involved in substrate binding and that H192 is used not only for substrate interaction, but for cofactor binding of drDDC as well. Through comparative analysis, the results also provide insight into the structure-function relationship of other insect DDC-like proteins.

  6. Comparison of Measurements of Autoantibodies to Glutamic Acid Decarboxylase and Islet Antigen-2 in Whole Blood Eluates from Dried Blood Spots Using the RSR-Enzyme Linked Immunosorbent Assay Kits and In-House Radioimmunoassays

    Directory of Open Access Journals (Sweden)

    Anders Persson

    2010-01-01

    Full Text Available To evaluate the performance of dried blood spots (DBSs with subsequent analyses of glutamic acid decarboxylase (GADA and islet antigen-2 (IA-2A with the RSR-ELISAs, we selected 80 children newly diagnosed with type 1 diabetes and 120 healthy women. DBSs from patients and controls were used for RSR-ELISAs while patients samples were analysed also with in-house RIAs. The RSR-ELISA-GADA performed well with a specificity of 100%, albeit sensitivity (46% was lower compared to in RIA (56%; P=.008. No prozone effect was observed after dilution of discrepant samples. RSR-ELISA-IA-2A achieved specificity of 69% and sensitivity was lower (59% compared with RIA (66%; P<.001. Negative or low positive patients and control samples in the RSR-ELISA-IA-2A increased after dilution. Eluates from DBS can readily be used to analyse GADA with the RSR-ELISA, even if low levels of autoantibodies were not detected. Some factor could disturb RSR-ELISA-IA-2A analyses.

  7. Post-transcriptional regulation of ornithine decarboxylase in Xenopus laevis oocytes.

    Science.gov (United States)

    Bassez, T; Paris, J; Omilli, F; Dorel, C; Osborne, H B

    1990-11-01

    The level at which ornithine decarboxylase expression is regulated in growing oocytes has been investigated. Immunoprecipitation of the in vivo labelled proteins showed that ornithine decarboxylase accumulated less rapidly in stage IV oocytes than in previtellogenic stage I + II oocytes. Quantitative Northern analysis showed that ornithine decarboxylase mRNA is abundant in oocytes (about 8 x 10(8) transcripts/cell) and this number does not significantly change during oogenesis. Polysome analysis showed that this mRNA is present in polysomes in stage I + II oocytes but has passed into puromycin-insensitive mRNP particles by stage IV of oogenesis. Therefore, during the growth phase of oogenesis, ornithine decarboxylase expression is regulated at a translational level. These results are discussed relative to the temporal expression of ornithine decarboxylase and of other proteins whose expression also decreases during oogenesis. In order to perform these experiments, the cDNA (XLODC1) corresponding to Xenopus laevis ornithine decarboxylase mRNA was cloned and sequenced.

  8. Reduced by-product formation and modified oxygen availability improve itaconic acid production in Aspergillus niger.

    NARCIS (Netherlands)

    Li, A.; Pfelzer, N.; Zuijderwijk, R.; Brickwedde, A.; Zeijl, C. van; Punt, P.

    2013-01-01

    Aspergillus niger has an extraordinary potential to produce organic acids as proven by its application in industrial citric acid production. Previously, it was shown that expression of the cis-aconitate decarboxylase gene (cadA) from Aspergillus terreus converted A. niger into an itaconic acid produ

  9. Structural Basis of the Substrate Specificity and Enzyme Catalysis of a Papaver somniferum Tyrosine Decarboxylase

    Science.gov (United States)

    Guan, Huai; Song, Shuaibao; Robinson, Howard; Liang, Jing; Ding, Haizhen; Li, Jianyong; Han, Qian

    2017-01-01

    Tyrosine decarboxylase (TyDC), a type II pyridoxal 5′-phosphate decarboxylase, catalyzes the decarboxylation of tyrosine. Due to a generally high sequence identity to other aromatic amino acid decarboxylases (AAADs), primary sequence information is not enough to understand substrate specificities with structural information. In this study, we selected a typical TyDC from Papaver somniferum as a model to study the structural basis of AAAD substrate specificities. Analysis of the native P. somniferum TyDC crystal structure and subsequent molecular docking and dynamics simulation provide some structural bases that explain substrate specificity for tyrosine. The result confirmed the previous proposed mechanism for the enzyme selectivity of indolic and phenolic substrates. Additionally, this study yields the first crystal structure for a plant type II pyridoxal-5'-phosphate decarboxylase. PMID:28232911

  10. Detection and transfer of the glutamate decarboxylase gene in Streptococcus thermophilus

    Science.gov (United States)

    GABA (gamma-aminobutyric acid) is generated from glutamate by the action of glutamic acid decarboxylase (GAD) and characterized by hypotensive, diuretic and tranquilizing effects in humans and animals. The production of GABA by lactic acid starter bacteria would enhance the functionality of fermen...

  11. Molecular analysis of the glutamate decarboxylase locus in Streptococcus thermophilus ST110

    Science.gov (United States)

    GABA ('-aminobutyric acid) is generated from glutamate by the action of glutamic acid decarboxylase (GAD) and characterized by hypotensive, diuretic and tranquilizing effects in humans and animals. The production of GABA by lactic acid starter bacteria would enhance the functionality of fermented da...

  12. Two isoforms of glutamate decarboxylase in Arabidopsis are regulated by calcium/calmodulin and differ in organ distribution.

    Science.gov (United States)

    Zik, M; Arazi, T; Snedden, W A; Fromm, H

    1998-08-01

    The nucleotide sequences of cDNAs encoding two isoforms of Arabidopsis glutamate decarboxylase, designated GAD1 (57.1 kDa) and GAD2 (56.1 kDa) and sharing 82% identical amino acid sequences, were determined. The recombinant proteins bound [35S] calmodulin (CaM) in the presence of calcium, and a region of 30-32 amino acids from the C-terminal of each isoform was sufficient for CaM binding when fused to glutathione S-transferase. Full-length GAD1 and GAD2 were expressed in Sf9 insect cells infected with recombinant baculovirus vectors. Recombinant proteins were partially purified by CaM affinity chromatography and were found to exhibit glutamate decarboxylase activity, which was dependent on the presence of Ca2+/CaM at pH 7.3. Southern hybridizations with GAD gene-specific probes suggest that Arabidopsis possesses one gene related to GAD1 and one to GAD2. Northern hybridization and western blot analysis revealed that GAD1 was expressed only in roots and GAD2 in roots, leaves, inflorescence stems and flowers. Our study provides the first evidence for the occurrence of multiple functional Ca2+/CaM-regulated GAD gene products in a single plant, suggesting that regulation of Arabidopsis GAD activity involves modulation of isoform-specific gene expression and stimulation of the catalytic activity of GAD by calcium signalling via CaM.

  13. Enhancing the Activity of Glutamate Decarboxylase from Lactobacillus brevis by Directed Evolution☆

    Institute of Scientific and Technical Information of China (English)

    Ling Lin; Sheng Hu; Kai Yu; Jun Huang; Shanjing Yao; Yinlin Lei; Guixiang Hu; Lehe Mei

    2014-01-01

    Glutamate decarboxylase (GAD, EC4.1.1.15) can catalyze the decarboxylation of L-glutamate to form γ-aminobutyrate (GABA), which is in great demand in some foods and pharmaceuticals. In our previous study, gad, the gene coding glutamate decarboxylase from Lactobacil us brevis CGMCC 1306, was cloned and its soluble expression was realized. In this study, error-prone PCR was conducted to improve its activity, followed by a screening. Mutant Q51H with high activity [55.4 mmol·L−1·min−1·(mg protein)−1, 120%higher than that of the wild type at pH 4.8] was screened out from the mutant library. In order to investigate the potential role of this site in the regulation of enzymatic activity, site-directed saturation mutagenesis at site 51 was carried out, and three specific mutants, N-terminal truncated GAD, Q51P, and Q51L, were identified. The kinetic parameters of the three mutants and Q51H were characterized. The results reveal that aspartic acid at site 88 and N-terminal domain are essential to the activity as well as correct folding of GAD. This study not only improves the activity of GAD, but also sheds new light on the structure–function relationship of GAD.

  14. Assessment of CD4+ T cell responses to glutamic acid decarboxylase 65 using DQ8 tetramers reveals a pathogenic role of GAD65 121-140 and GAD65 250-266 in T1D development.

    Directory of Open Access Journals (Sweden)

    I-Ting Chow

    Full Text Available Susceptibility to type 1 diabetes (T1D is strongly associated with MHC class II molecules, particularly HLA-DQ8 (DQ8: DQA1*03:01/DQB1*03:02. Monitoring T1D-specific T cell responses to DQ8-restricted epitopes may be key to understanding the immunopathology of the disease. In this study, we examined DQ8-restricted T cell responses to glutamic acid decarboxylase 65 (GAD65 using DQ8 tetramers. We demonstrated that GAD65 121-140 and GAD65 250-266 elicited responses from DQ8+ subjects. Circulating CD4+ T cells specific for these epitopes were detected significantly more often in T1D patients than in healthy individuals after in vitro expansion. T cell clones specific for GAD65 121-140 and GAD65 250-266 carried a Th1-dominant phenotype, with some of the GAD65 121-140-specific T cell clones producing IL-17. GAD65 250-266-specific CD4+ T cells could also be detected by direct ex vivo staining. Analysis of unmanipulated peripheral blood mononuclear cells (PBMCs revealed that GAD65 250-266-specific T cells could be found in both healthy and diabetic individuals but the frequencies of specific T cells were higher in subjects with type 1 diabetes. Taken together, our results suggest a proinflammatory role for T cells specific for DQ8-restricted GAD65 121-140 and GAD65 250-266 epitopes and implicate their possible contribution to the progression of T1D.

  15. Tyrosine decarboxylase activity of enterococci grown in media with different nutritional potential: tyramine and 2-phenylethylamine accumulation and tyrDC gene expression

    Directory of Open Access Journals (Sweden)

    Eleonora eBargossi

    2015-04-01

    Full Text Available The ability to accumulate tyramine and 2-phenylethylamine by two strains of Enterococcus faecalis and two strains Enterococcus faecium was evaluated in two cultural media added or not with tyrosine. All the enterococcal strains possessed a tyrDC which determined tyramine accumulation in all the conditions tested, independently on the addition of high concentration of free tyrosine. Enterococci differed in rate and level of biogenic amines accumulation. E. faecalis EF37 and E. faecium FC12 produced tyramine in high amount since the exponential growth phase, while 2-phenylethylamine was accumulated when tyrosine was depleted. Enterococcus faecium FC12 and E. faecalis ATCC 29212 showed a slower tyraminogenic activity which took place mainly in the stationary phase up to 72 h of incubation. Moreover, E. faecalis ATCC 29212 produced 2-phenylethylamine only in the media without tyrosine added. In BHI added or not with tyrosine the tyrDC gene expression level differed considerably depending on the strains and the growth phase. In particular, the tyrDC gene expression was high during the exponential phase in rich medium for all the strains and subsequently decreased except for E. faecium FC12. Even if tyrDC presence is common among enterococci, this study underlines the extremely variable decarboxylating potential of strains belonging to the same species, suggesting strain-dependent implications in food safety.

  16. Expression of Recombinant Tryptophan Decarboxylase in Different Subcellular Compartments in Tobacco Plant%重组色氨酸脱羧酶在烟草不同亚细胞区室的表达

    Institute of Scientific and Technical Information of China (English)

    王淼; 李秋荣; Stefano Di DIORE

    2002-01-01

    The gene encoded for tryptophan decarboxylase (TDC), which is the key enzyme in terpenoil indole alkaloids pathway, was targeted to different subcellular compartments and stably expressed in transgenic tobacco (Nicotiana tabacum L.) plants at the levels detected by Western blot and tryptamine accumulation analysis. It was shown that the TDC was located in subcellular compartments, the chloroplasts and cytosol. The recombinant TDC targeted to chloroplasts and cytosol in tobacco plants was effectively expressed as soluble protein by Western blot analysis and enzymatic assay. The level of tryptamine accumulation in chloroplast was higher than that in cytosol and very low in vacuole and endoplasmic reticulum (ER) to be hardly detected by Western blot analysis. It was indicated that the highest amount of tryptamine was in chloroplasts, lower in endoplasmic reticula and the lowest in vacuoles as compared to those in wild type plants. The TDC targeted to different subcellular compartments of tobacco plants and its expression level were studied by different nucleotide sequences coding signal peptides at 5′-end of tdc gene in order to know the effects of the TDC in compartmentation on its functionality.%将萜烯类吲哚生物碱代谢关键酶--色氨酸脱羧酶(TDC)的编码基因转到烟草(Nicotiana tabacum L.)植物体内,标定在不同的亚细胞区室表达。通过蛋白免疫印迹法和色胺在植物体内的累积量测定分析,对转基因植物进行筛选。结果表明,TDC在叶绿体和胞液中高效表达,TDC在叶绿体中的表达水平最高,高于在胞液中的表达,在内质网和液泡中表达水平很低,用蛋白免疫印迹法未检出。

  17. 谷氨酸脱羧酶抗体微量平板放射结合检测法的建立与初步应用%Micro-plate radiobinding assay of autoantibody to glutamic acid decarboxylase

    Institute of Scientific and Technical Information of China (English)

    黄干; 金河来; 王霞; 李卉; 张松; 周智广

    2008-01-01

    Objective The purpose of this study was to develop a high-throughput micro-plate radiobinding assay (RBA) of glutamic acid decarboxylase antibody (GAD-Ab) and to evaluate its clinical application. Methods 35labeled GAD65 antigen was incubated with sera for 24 h on a 96-well plate, and then transferred to the Millipore plate coated with protein A, which was washed with 4℃ PBS buffer, and then counted by a liquid scintillation counter. The GAD-Ab results were expressed by WHO standard unit (U/ml). A total of 224 healthy controls, 162 patients with type 1 diabetes mellitus(T1DM) and 210 patients with newly diagnosed type 2 diabetes (T2DM) were recruited. A total of 119 TI DM and healthy cases with gradually changing GAD-Ab levels were selected to compare the consistency of micro-plate RBA with conventional radioligand assay (RLA). Blood samples were obtained from the peripheral vein and finger tip in 32 healthy controls, 35 T1DM and 24 T2DM patients, and tested with micro-plate RBA and then compared with the conventional RLA to investigate the reliability of finger tip sampling. Linear correlation,student's t-test, variance analysis and receiver operating characteristic (ROC) curve were performed using SPSS 11.5. Results (1) The optimized conditions of micro-plate RBA included 2 μl serum incubated with3 ×104 counts/min 35S-GAD for 24 h under slow vibration, antigen-antibody compounds washed 10 times by 4℃ PBS buffer, and radioactivity counted with Optiphase Supermix scintillation liquid. (2)The intra-batch CV of the micro-plate RBA was 3.8%- 10.2%, and the inter-batch CV was 5.6%- 11.9%. The linearity analysis showed a good correlation when the GAD-Ab in serum samples ranged from 40.3 to 664 U/ml and the detection limit of measurement was 3.6 U/ml. The results from Diabetes Autoantibody Standardization Program (DASP) 2005 showed that the sensitivity and specificity for GAD-Ab were 78% (39 positive among 50 new-onset T1DM) and 98% (2 positive among 100 healthy

  18. Ornithine Decarboxylase Activity Is Required for Prostatic Budding in the Developing Mouse Prostate.

    Directory of Open Access Journals (Sweden)

    Melissa Gamat

    Full Text Available The prostate is a male accessory sex gland that produces secretions in seminal fluid to facilitate fertilization. Prostate secretory function is dependent on androgens, although the mechanism by which androgens exert their effects is still unclear. Polyamines are small cationic molecules that play pivotal roles in DNA transcription, translation and gene regulation. The rate-limiting enzyme in polyamine biosynthesis is ornithine decarboxylase, which is encoded by the gene Odc1. Ornithine decarboxylase mRNA decreases in the prostate upon castration and increases upon administration of androgens. Furthermore, testosterone administered to castrated male mice restores prostate secretory activity, whereas administering testosterone and the ornithine decarboxylase inhibitor D,L-α-difluromethylornithine (DFMO to castrated males does not restore prostate secretory activity, suggesting that polyamines are required for androgens to exert their effects. To date, no one has examined polyamines in prostate development, which is also androgen dependent. In this study, we showed that ornithine decarboxylase protein was expressed in the epithelium of the ventral, dorsolateral and anterior lobes of the adult mouse prostate. Ornithine decarboxylase protein was also expressed in the urogenital sinus (UGS epithelium of the male and female embryo prior to prostate development, and expression continued in prostatic epithelial buds as they emerged from the UGS. Inhibiting ornithine decarboxylase using DFMO in UGS organ culture blocked the induction of prostatic buds by androgens, and significantly decreased expression of key prostate transcription factor, Nkx3.1, by androgens. DFMO also significantly decreased the expression of developmental regulatory gene Notch1. Other genes implicated in prostatic development including Sox9, Wif1 and Srd5a2 were unaffected by DFMO. Together these results indicate that Odc1 and polyamines are required for androgens to exert their

  19. Cloning and nucleotide sequence of wild type and a mutant histidine decarboxylase from Lactobacillus 30a.

    Science.gov (United States)

    Vanderslice, P; Copeland, W C; Robertus, J D

    1986-11-15

    Prohistidine decarboxylase from Lactobacillus 30a is a protein that autoactivates to histidine decarboxylase by cleaving its peptide chain between serines 81 and 82 and converting Ser-82 to a pyruvoyl moiety. The pyruvoyl group serves as the prosthetic group for the decarboxylation reaction. We have cloned and determined the nucleotide sequence of the gene for this enzyme from a wild type strain and from a mutant with altered autoactivation properties. The nucleotide sequence modifies the previously determined amino acid sequence of the protein. A tripeptide missed in the chemical sequence is inserted, and three other amino acids show conservative changes. The activation mutant shows a single change of Gly-58 to an Asp. Sequence analysis up- and downstream from the gene suggests that histidine decarboxylase is part of a polycistronic message, and that the transcriptional promotor region is strongly homologous to those of other Gram-positive organisms.

  20. Role of ornithine decarboxylase in breast cancer

    Institute of Scientific and Technical Information of China (English)

    Wensheng Deng; Xian Jiang; Yu Mei; Jingzhong Sun; Rong Ma; Xianxi Liu; Hui Sun; Hui Tian; Xueying Sun

    2008-01-01

    Ornithine decarboxylase (ODC), the rate-limiting enzyme in polyamine biosynthesis that decarboxylates ornithine to putrescine, has become a promising target for cancer research. The aim of this study is to investigate the role of ODC in breast cancer. We detected expression of ODC in breast cancer tissues and four breast cancer cell lines, and transfected breast cancer cells with an adenoviral vector carrying antisense ODC (rAd-ODC/Ex3as) and examined their growth and migration.ODC was overexpressed in breast cancer tissues and cell lines compared with non-tumor tissues and normal breast epithelial celis,and there was a positive correlation between the level of ODC mRNA and the staging of tumors.The expression of ODC correlated with cyclin D1,a cell cycle protein,in synchronized breast cancer MDA-MB-231 cells.Gene transfection of rAd-ODC/Ex3as markedly down-regulated expression Of ODC and cyclin D1,resulting in suppression of proliferation and cell cycle arrest at G0-G1 phase,and the inhibifion of colony formation,an anchorage-independent growth pattern,and the migratory ability of MDA-MB-231 cells.rAd-ODC/Ex3as also markedly reduced the concentration of putrescine,but not spermidine or spermine,in MDA-MB-231 cells.The results suggested that the ODC gene might act as aprognostic factor for breast cancer and it could be a promising therapeutic target.

  1. Resolution of brewers' yeast pyruvate decarboxylase into two isozymes.

    Science.gov (United States)

    Kuo, D J; Dikdan, G; Jordan, F

    1986-03-01

    A novel purification method was developed for brewers' yeast pyruvate decarboxylase (EC 4.1.1.1) that for the first time resolved the enzyme into two isozymes on DEAE-Sephadex chromatography. The isozymes were found to be distinct according to sodium dodecyl sulfate polyacrylamide gel electrophoresis: the first one to be eluted gave rise to one band, the second to two bands. The isozymes were virtually the same so far as specific activity, KM, inhibition kinetics and irreversible binding properties by the mechanism-based inhibitor (E)-4-(4-chlorophenyl)-2-oxo-3-butenoic acid are concerned. This finding resolves a longstanding controversy concerning the quaternary structure of this enzyme.

  2. Conformational Stabilization of Rat S-Adenosylmethionine Decarboxylase by Putrescine

    OpenAIRE

    和田, 牧子; 白幡, 晶

    2010-01-01

    The activity and processing of mammalian S-adenosylmethionine decarboxylase (AdoMetDC) is stimulated by putrescine. To obtain new insights into the mechanism through which putrescine stimulates AdoMetDC, we investigated conformational changes in rat prostate AdoMetDC in the presence or absence of putrescine. We examined the reactivity of purified rat prostate AdoMetDC to the SH-reagent iodoacetic acid (IAA) and its susceptibility to proteolysis in the presence or absence of putrescine using m...

  3. Disease-specific monoclonal antibodies targeting glutamate decarboxylase impair GABAergic neurotransmission and affect motor learning and behavioral functions

    Directory of Open Access Journals (Sweden)

    Mario U Manto

    2015-03-01

    Full Text Available Autoantibodies to the smaller isoform of glutamate decarboxylase can be found in patients with type 1 diabetes and a number of neurological disorders, including stiff-person syndrome, cerebellar ataxia and limbic encephalitis. The detection of disease-specific autoantibody epitopes led to the hypothesis that distinct glutamate decarboxylase autoantibodies may elicit specific neurological phenotypes. We explored the in vitro/in vivo effects of well-characterized monoclonal glutamate decarboxylase antibodies. We found that glutamate decarboxylase autoantibodies present in patients with stiff person syndrome (n = 7 and cerebellar ataxia (n = 15 recognized an epitope distinct from that recognized by glutamate decarboxylase autoantibodies present in patients with type 1 diabetes mellitus (n = 10 or limbic encephalitis (n = 4. We demonstrated that the administration of a monoclonal glutamate decarboxylase antibody representing this epitope specificity (1 disrupted in vitro the association of glutamate decarboxylase with γ-Aminobutyric acid containing synaptic vesicles, (2 depressed the inhibitory synaptic transmission in cerebellar slices with a gradual time course and a lasting suppressive effect, (3 significantly decreased conditioned eyelid responses evoked in mice, with no modification of learning curves in the classical eyeblink-conditioning task, (4 markedly impaired the facilitatory effect exerted by the premotor cortex over the motor cortex in a paired-pulse stimulation paradigm, and (5 induced decreased exploratory behavior and impaired locomotor function in rats. These findings support the specific targeting of glutamate decarboxylase by its autoantibodies in the pathogenesis of stiff-person syndrome and cerebellar ataxia. Therapies of these disorders based on selective removal of such glutamate decarboxylase antibodies could be envisioned.

  4. Retina maturation following administration of thyroxine in developing rats: effects on polyamine metabolism and glutamate decarboxylase.

    Science.gov (United States)

    Macaione, S; Di Giorgio, R M; Nicotina, P A; Ientile, R

    1984-08-01

    The effects of subcutaneous daily treatment with thyroxine on cell proliferation, differentiation, polyamines, and gamma-aminobutyric acid metabolism in the rat retina were studied during the first 20 postnatal days. The retinal layers of the treated rats displayed an enhanced cell differentiation which reached its maximum 9-12 days from birth; but this effect stopped very quickly and was finished by the 20th postnatal day. Primarily there was an increase in ornithine decarboxylase activity which was accompanied by an increase in putrescine, spermidine, and spermine levels. S-Adenosylmethionine decarboxylase was induced later than ODC; corresponding with the enhanced synaptogenesis, glutamate decarboxylase increased 15-fold between the fourth and 15th days. Our data are consistent with the hypothesis that thyroxine may exert some of its effects by inducing the enzymes which regulate polyamine metabolism and synaptogenesis.

  5. 产气肠杆菌α-乙酰乳酸脱羧酶基因的克隆表达及鉴定%Cloning and Expression of α-Acetolactate Decarboxylase Gene from Enterobacter aerogenes

    Institute of Scientific and Technical Information of China (English)

    王爱娥; 荫俊

    2003-01-01

    根据已知α-乙酰乳酸脱羧酶(α-acetolactate decarboxylase,ALDC)的基因序列,用PCR法从产气肠杆菌(Ebterobacter aerogenes)中克隆到约0.8kb的DNA片段,经DNA测序证明是ALDC基因,将该基因重组到质粒pBV220中,转化大肠杆菌,实现了高表达,获得了目的蛋白表达量约50%的转化子;表达产物经鉴定具有ALDC酶活性,为可溶性表达.为下一步应用基因工程手段对其进行改造奠定了基础.

  6. 苦瓜果实S-腺苷蛋氨酸脱羧酶基因McSAMDC的克隆、表达及亚细胞定位%Cloning, Expression and Subcellular Localization of S-adenosylmethionine Decarboxylase Gene (McSAMDC)Gene from Fruit in Momordica charantia L.

    Institute of Scientific and Technical Information of China (English)

    高山; 陈桂信; 许端祥; 钟开勤; 林义章; 潘东明

    2013-01-01

    The full length cDNA sequence of S-adenosylmethionine decarboxylase (SAMDC) gene named McSAMDC (GenBank accession No.:KC632099) was cloned by 3′RACE technique based on the related EST sequence from the normalized Full-Length cDNA library of bitter gourd fruit.The cDNA sequence is 1900 bp in full length with a 501 bp 5′-UTR and a 325 bp 3′-UTR.The cDNA sequence consists of three ORFs (tiny ORF,upstream ORF and main ORF),and the main ORF was 1077 bp encoding 358 amino acids with a calculated molecular weight of 39.31 ku.The mORF deduced protein had two conserved function domains (proenzyme cleavage site and rapid degradation of SAMDC protein domain).In the secondary structure,Random coil,α-helix,Extended strand,and β-tum was 45.53%,29.33%,19.83% and 5.31%,respectively.Amino acid sequence alignment showed the McSAMDC shared high identity with Arabidopsis thaliana (CAA69073.1),Arabidopsis lyrata subsp.(XP 002882231.1),and Brassica juncea (AAS45435.1) as 69%,68% and 68%.Subcellular localization analysis showed that the mORF was mainly found in the cytoplasm.Fluorescent quantitative PCR analysis showed the McSAMDC gene was expressed at the highest level at the fruit enlargement stage and rapidly decreased thereafter,and the expression level was continuously increased from the mature green stage until full mature stage.%根据已构建苦瓜果实均一化文库中获得的1个与SAMDC基因相关的EST序列,采用3′RACE技术,克隆获得1个苦瓜SAMDC基因的cDNA全长序列,命名为McSAMDC(GenBank登录号为KC632099).生物信息分析结果表明,该cDNA全长l900bp,5′UTR和3′UTR分别长501、325bp.该cDNA序列存在3个开放读码框(微型tORF、上游读码框uORF和主读码框mORF),其中mORF长1077bp,编码358个氨基酸,预测分子量为39.31ku,含有酶原剪切位点结构域和蛋白快速降解有关的PEST二个保守结构域.二级结构分析显示,McSAMDC含有无规卷曲(45.53%)、α-螺旋(29.33

  7. A coenzyme-independent decarboxylase/oxygenase cascade for the efficient synthesis of vanillin.

    Science.gov (United States)

    Furuya, Toshiki; Miura, Misa; Kino, Kuniki

    2014-10-13

    Vanillin is one of the most widely used flavor compounds in the world as well as a promising versatile building block. The biotechnological production of vanillin from plant-derived ferulic acid has attracted much attention as a new alternative to chemical synthesis. One limitation of the known metabolic pathway to vanillin is its requirement for expensive coenzymes. Here, we developed a novel route to vanillin from ferulic acid that does not require any coenzymes. This artificial pathway consists of a coenzyme-independent decarboxylase and a coenzyme-independent oxygenase. When Escherichia coli cells harboring the decarboxylase/oxygenase cascade were incubated with ferulic acid, the cells efficiently synthesized vanillin (8.0 mM, 1.2 g L(-1) ) via 4-vinylguaiacol in one pot, without the generation of any detectable aromatic by-products. The efficient method described here might be applicable to the synthesis of other high-value chemicals from plant-derived aromatics.

  8. Biosynthetic arginine decarboxylase in phytopathogenic fungi.

    Science.gov (United States)

    Khan, A J; Minocha, S C

    1989-01-01

    It has been reported that while bacteria and higher plants possess two different pathways for the biosynthesis of putrescine, via ornithine decarboxylase (ODC) and arginine decarboxylase (ADC); the fungi, like animals, only use the former pathway. We found that contrary to the earlier reports, two of the phytopathogenic fungi (Ceratocystis minor and Verticillium dahliae) contain significant levels of ADC activity with very little ODC. The ADC in these fungi has high pH optimum (8.4) and low Km (0.237 mM for C. minor, 0.103 mM for V. dahliae), and is strongly inhibited by alpha-difluoromethylarginine (DFMA), putrescine and spermidine, further showing that this enzyme is probably involved in the biosynthesis of polyamines and not in the catabolism of arginine as in Escherichia coli. The growth of these fungi is strongly inhibited by DFMA while alpha-difluoromethylornithine (DFMO) has little effect.

  9. Structural and Mechanistic Studies on Klebsiella pneumoniae 2-Oxo-4-hydroxy-4-carboxy-5-ureidoimidazoline Decarboxylase

    Energy Technology Data Exchange (ETDEWEB)

    French, Jarrod B.; Ealick, Steven E. (Cornell)

    2010-11-12

    The stereospecific oxidative degradation of uric acid to (S)-allantoin was recently shown to proceed via three enzymatic steps. The final conversion is a decarboxylation of the unstable intermediate 2-oxo-4-hydroxy-4-carboxy-5-ureidoimidazoline (OHCU) and is catalyzed by OHCU decarboxylase. Here we present the structures of Klebsiella pneumoniae OHCU decarboxylase in unliganded form and with bound allantoin. These structures provide evidence that ligand binding organizes the active site residues for catalysis. Modeling of the substrate and intermediates provides additional support for this hypothesis. In addition we characterize the steady state kinetics of this enzyme and report the first OHCU decarboxylase inhibitor, allopurinol, a structural isomer of hypoxanthine. This molecule is a competitive inhibitor of K. pneumoniae OHCU decarboxylase with a K{sub i} of 30 {+-} 2 {micro}m. Circular dichroism measurements confirm structural observations that this inhibitor disrupts the necessary organization of the active site. Our structural and biochemical studies also provide further insights into the mechanism of catalysis of OHCU decarboxylation.

  10. The ornithine decarboxylase gene of Caenorhabditis elegans: Cloning, mapping and mutagenesis

    Energy Technology Data Exchange (ETDEWEB)

    Macrae, M.; Coffino, P. [Univ. of California, San Francisco, CA (United States); Plasterk, R.H.A. [Netherlands Cancer Institute, Amsterdam (Netherlands)

    1995-06-01

    The gene (odc-1) encoding ornithine decarboxylase, a key enzyme in polyamine biosynthesis, was cloned and characterized. Two introns interrupt the coding sequence of the gene. The deduced protein contains 442 amino acids and is homologous to ornithine decarboxylases of other eukaryotic species. In vitro translation of a transcript of the cDNA yielded an enzymatically active product. The mRNA is 1.5 kb in size and is formed by trans-splicing to SL1, a common 5{prime} RNA segment. odc-1 maps to the middle of LG V, between dpy-11 and unc-42 and near a breakpoint of the nDf32 deficiency strain. Enzymatic activity is low in starved 1 (L1) larva and, after feeding, rises progressively as the worms develop. Targeted gene disruption was used to create a null allele. Homozygous mutants are normally viable and show no apparent defects, with the exception of a somewhat reduced brood size. In vitro assays for ornithine decarboxylase activity, however, show no detectable enzymatic activity, suggesting that ornithine decarboxylase is dispensible for nematode growth in the laboratory. 37 refs., 6 figs., 1 tab.

  11. Structures of Bacterial Biosynthetic Arginine Decarboxylases

    Energy Technology Data Exchange (ETDEWEB)

    F Forouhar; S Lew; J Seetharaman; R Xiao; T Acton; G Montelione; L Tong

    2011-12-31

    Biosynthetic arginine decarboxylase (ADC; also known as SpeA) plays an important role in the biosynthesis of polyamines from arginine in bacteria and plants. SpeA is a pyridoxal-5'-phosphate (PLP)-dependent enzyme and shares weak sequence homology with several other PLP-dependent decarboxylases. Here, the crystal structure of PLP-bound SpeA from Campylobacter jejuni is reported at 3.0 {angstrom} resolution and that of Escherichia coli SpeA in complex with a sulfate ion is reported at 3.1 {angstrom} resolution. The structure of the SpeA monomer contains two large domains, an N-terminal TIM-barrel domain followed by a {beta}-sandwich domain, as well as two smaller helical domains. The TIM-barrel and {beta}-sandwich domains share structural homology with several other PLP-dependent decarboxylases, even though the sequence conservation among these enzymes is less than 25%. A similar tetramer is observed for both C. jejuni and E. coli SpeA, composed of two dimers of tightly associated monomers. The active site of SpeA is located at the interface of this dimer and is formed by residues from the TIM-barrel domain of one monomer and a highly conserved loop in the {beta}-sandwich domain of the other monomer. The PLP cofactor is recognized by hydrogen-bonding, {pi}-stacking and van der Waals interactions.

  12. Retinoic acid-mediated gene expression in transgenic reporter zebrafish.

    Science.gov (United States)

    Perz-Edwards, A; Hardison, N L; Linney, E

    2001-01-01

    Retinoic acid-mediated gene activation is important for normal vertebrate development. The size and nature of retinoic acid make it difficult to identify the precise cellular location of this signaling molecule throughout an embryo. Additionally, retinoic acid (RA) signaling is regulated by a complex combination of receptors, coactivators, and antagonizing proteins. Thus, in order to integrate these signals and identify regions within a whole developing embryo where cells can respond transcriptionally to retinoic acid, we have used a reporter transgenic approach. We have generated several stable lines of transgenic zebrafish which use retinoic acid response elements to drive fluorescent protein expression. In these zebrafish lines, transgene expression is localized to regions of the neural tube, retina, notochord, somites, heart, pronephric ducts, branchial arches, and jaw muscles in embryos and larvae. Transgene expression can be induced in additional regions of the neural tube and retina as well as the immature notochord, hatching gland, enveloping cell layer, and fin by exposing embryos to retinoic acid. Treatment with retinoic acid synthase inhibitors, citral and diethylaminobenzaldehyde (DEAB), during neurulation, greatly reduces transgene expression. DEAB treatment of embryos at gastrulation phenocopies the embryonic effects of vitamin A deprivation or targeted disruption of the RA synthase retinaldehyde dehydrogenase-2 in other vertebrates. Together these data suggest that the reporter expression we see in zebrafish is dependent upon conserved vertebrate pathways of RA synthesis.

  13. Expression of fatty acid synthase in nonalcoholic fatty liver disease.

    Science.gov (United States)

    Dorn, Christoph; Riener, Marc-Oliver; Kirovski, Georgi; Saugspier, Michael; Steib, Kathrin; Weiss, Thomas S; Gäbele, Erwin; Kristiansen, Glen; Hartmann, Arndt; Hellerbrand, Claus

    2010-03-25

    Nonalcoholic fatty liver disease (NAFLD) is characterized by hepatic lipid accumulation which starts with simple hepatic steatosis and may progress toward inflammation (nonalcoholic steatohepatitis [NASH]). Fatty acid synthase (FASN) catalyzes the last step in fatty acid biosynthesis, and thus, it is believed to be a major determinant of the maximal hepatic capacity to generate fatty acids by de novo lipogenesis. The aim of this study was to analyze the correlation between hepatic steatosis and inflammation with FASN expression. In vitro incubation of primary human hepatocytes with fatty acids dose-dependently induced cellular lipid-accumulation and FASN expression, while stimulation with TNF did not affect FASN levels. Further, hepatic FASN expression was significantly increased in vivo in a murine model of hepatic steatosis without significant inflammation but not in a murine NASH model as compared to control mice. Also, FASN expression was not increased in mice subjected to bile duct ligation, an experimental model characterized by severe hepatocellular damage and inflammation. Furthermore, FASN expression was analyzed in 102 human control or NAFLD livers applying tissue micro array technology and immunohistochemistry, and correlated significantly with the degree of hepatic steatosis, but not with inflammation or ballooning of hepatocytes. Quantification of FASN mRNA expression in human liver samples confirmed significantly higher FASN levels in hepatic steatosis but not in NASH, and expression of SREBP1, which is the main transcriptional regulator of FASN, paralleled FASN expression levels in human and experimental NAFLD. In conclusion, the transcriptional induction of FASN expression in hepatic steatosis is impaired in NASH, while hepatic inflammation in the absence of steatosis does not affect FASN expression, suggesting that FASN may serve as a new diagnostic marker or therapeutic target for the progression of NAFLD.

  14. Ornithine decarboxylase gene is overexpressed in colorectal carcinoma

    Institute of Scientific and Technical Information of China (English)

    Hai-Yan Hu; Bing Zhang; Xian-Xi Liu; Chun-Ying Jiang; Yi Lu; Shi-Lian Liu; Ji-Feng Bian; Xiao-Ming Wang; Zhao Geng; Yan Zhang

    2005-01-01

    AIM: To investigate the ornithine decarboxylase (ODC)gene expression in colorectal carcinoma, ODC mRNA was assayed by RT-PCR and ODC protein was detected by a monoclonal antibody against fusion of human colon ODC prepared by hybridoma technology.METHODS: Total RNA was extracted from human colorectal cancer tissues and their normal counterpart tissues. ODC mRNA levels were examined by RT-PCR.ODC genes amplified from RT-PCR were cloned into a prokaryotic vector pQE-30. The expressed proteins were purified by chromatography. Anti-ODC mAb was prepared with classical hybridoma techniques and used to determine the ODC expression in colon cancer tissues by immunohistochemical and Western blotting assay.RESULTS: A cell line, which could steadily secrete antiODC mAb, was selected through subcloning four times.Western blotting reconfirmed the mAb and ELISA showed that its subtype was IgG2a. RT-PCR showed that the ODC mRNA level increased greatly in colon cancer tissues (P<0.01). Immunohistochemical staining showed that colorectal carcinoma cells expressed a significantly higher level of ODC than normal colorectal mucosa (98.6±1.03%vs 5.26±5%, P<0.01).CONCLUSION: ODC gene overexpression is significantly related to human colorectal carcinoma. ODC gene expression may be a marker for the gene diagnosis and therapy of colorectal carcinoma.

  15. Expression of heteromeric amino acid transporters along the murine intestine.

    Science.gov (United States)

    Dave, Mital H; Schulz, Nicole; Zecevic, Marija; Wagner, Carsten A; Verrey, Francois

    2004-07-15

    Members of the new heterodimeric amino acid transporter family are composed of two subunits, a catalytic multitransmembrane spanning protein (light chain) and a type II glycoprotein (heavy chain). These transporters function as exchangers and thereby extend the transmembrane amino acid transport selectivity to specific amino acids. The heavy chain rBAT associates with the light chain b degrees (,+)AT to form a cystine and cationic amino acid transporter. The other heavy chain, 4F2hc, can interact with seven different light chains to form various transporters corresponding to systems L, y(+)L, asc or x(-)(c). The importance of some of these transporters in intestinal and renal (re)absorption of amino acids is highlighted by the fact that mutations in either the rBAT or b degrees (,+)AT subunit result in cystinuria whereas a defect in the y(+)-LAT1 light chain causes lysinuric protein intolerance. Here we investigated the localization of these transporters in intestine since both diseases are also characterized by altered intestinal amino acid absorption. Real time PCR showed organ-specific expression patterns for all transporter subunit mRNAs along the intestine and Western blotting confirmed these findings on the protein level. Immunohistochemistry demonstrated basolateral coexpression of 4F2hc, LAT2 and y(+)-LAT1 in stomach and small intestine, whereas rBAT and b degrees (,+)AT were found colocalizing on the apical side of small intestine epithelium. In stomach, 4F2hc and LAT2 were localized in H(+)/K(+)-ATPase-expressing parietal cells. The abundant expression of several members of the heterodimeric transporter family along the murine small intestine suggests their involvement in amino acids absorption. Furthermore, strong expression of rBAT, b degrees (,+)AT and y(+)-LAT1 in the small intestine explains the reduced intestinal absorption of some amino acid in patients with cystinuria or lysinuric protein intolerance.

  16. Role of glutamate decarboxylase-like protein 1 (GADL1) in taurine biosynthesis.

    Science.gov (United States)

    Liu, Pingyang; Ge, Xiaomei; Ding, Haizhen; Jiang, Honglin; Christensen, Bruce M; Li, Jianyong

    2012-11-30

    This manuscript concerns the tissue-specific transcription of mouse and cattle glutamate decarboxylase-like protein 1 (GADL1) and the biochemical activities of human GADL1 recombinant protein. Bioinformatic analysis suggested that GADL1 appears late in evolution, only being found in reptiles, birds, and mammals. RT-PCR determined that GADL1 mRNA is transcribed at high levels in mouse and cattle skeletal muscles and also in mouse kidneys. Substrate screening determined that GADL1, unlike its name implies, has no detectable GAD activity, but it is able to efficiently catalyze decarboxylation of aspartate, cysteine sulfinic acid, and cysteic acid to β-alanine, hypotaurine, and taurine, respectively. Western blot analysis verified the presence of GADL1 in mouse muscles, kidneys, C2C12 myoblasts, and C2C12 myotubes. Incubation of the supernatant of fresh muscle or kidney extracts with cysteine sulfinic acid resulted in the detection of hypotaurine or taurine in the reaction mixtures, suggesting the possible involvement of GADL1 in taurine biosynthesis. However, when the tissue samples were incubated with aspartate, no β-alanine production was observed. We proposed several possibilities that might explain the inactivation of ADC activity of GADL1 in tissue protein extracts. Although β-alanine-producing activity was not detected in the supernatant of tissue protein extracts, its potential role in β-alanine synthesis cannot be excluded. There are several inhibitors of the ADC activity of GADL1 identified. The discovery of GADL1 biochemical activities, in conjunction with its expression and activities in muscles and kidneys, provides some tangible insight toward establishing its physiological function(s).

  17. Experimental Evidence and In Silico Identification of Tryptophan Decarboxylase in Citrus Genus

    Directory of Open Access Journals (Sweden)

    Luigi De Masi

    2017-02-01

    Full Text Available Plant tryptophan decarboxylase (TDC converts tryptophan into tryptamine, precursor of indolealkylamine alkaloids. The recent finding of tryptamine metabolites in Citrus plants leads to hypothesize the existence of TDC activity in this genus. Here, we report for the first time that, in Citrus x limon seedlings, deuterium labeled tryptophan is decarboxylated into tryptamine, from which successively deuterated N,N,N-trimethyltryptamine is formed. These results give an evidence of the occurrence of the TDC activity and the successive methylation pathway of the tryptamine produced from the tryptophan decarboxylation. In addition, with the aim to identify the genetic basis for the presence of TDC, we carried out a sequence similarity search for TDC in the Citrus genomes using as a probe the TDC sequence reported for the plant Catharanthus roseus. We analyzed the genomes of both Citrus clementina and Citrus sinensis, available in public database, and identified putative protein sequences of aromatic l-amino acid decarboxylase. Similarly, 42 aromatic l-amino acid decarboxylase sequences from 23 plant species were extracted from public databases. Potential sequence signatures for functional TDC were then identified. With this research, we propose for the first time a putative protein sequence for TDC in the genus Citrus.

  18. The root-specific glutamate decarboxylase (GAD1) is essential for sustaining GABA levels in Arabidopsis.

    Science.gov (United States)

    Bouché, Nicolas; Fait, Aaron; Zik, Moriyah; Fromm, Hillel

    2004-05-01

    In plants, as in most eukaryotes, glutamate decarboxylase catalyses the synthesis of GABA. The Arabidopsis genome contains five glutamate decarboxylase genes and one of these genes (glutamate decarboxylase1; i.e. GAD1 ) is expressed specifically in roots. By isolating and analyzing three gad1 T-DNA insertion alleles, derived from two ecotypes, we investigated the potential role of GAD1 in GABA production. We also analyzed a promoter region of the GAD1 gene and show that it confers root-specific expression when fused to reporter genes. Phenotypic analysis of the gad1 insertion mutants revealed that GABA levels in roots were drastically reduced compared with those in the wild type. The roots of the wild type contained about sevenfold more GABA than roots of the mutants. Disruption of the GAD1 gene also prevented the accumulation of GABA in roots in response to heat stress. Our results show that the root-specific calcium/calmodulin-regulated GAD1 plays a major role in GABA synthesis in plants under normal growth conditions and in response to stress.

  19. Differential expression of cholangiocyte and ileal bile acid transporters following bile acid supplementation and depletion

    Institute of Scientific and Technical Information of China (English)

    N. Sertac Kip; Konstantinos N. Lazaridis; Anatoliy I. Masyuk; Patrick L. Splinter; Robert C. Huebert; Nicholas F. LaRusso

    2004-01-01

    AIM: We have previously demonstrated that cholangiocytes,the epithelial cells lining intrahepatic bile ducts, encode two functional bile acid transporters via alternative splicing of a single gene to facilitate bile acid vectorial transport.Cholangiocytes possess ASBT, an apical sodium-dependent bile acid transporter to take up bile acids, and t-ASBT, a basolateral alternatively spliced and truncated form of ASBT to efflux bile acids. Though hepatocyte and ileal bile acid transporters are in part regulated by the flux of bile acids,the effect of alterations in bile acid flux on the expression of t-ASBT in terminal ileocytes remains unclear. Thus, we tested the hypothesis that expression of ASBT and t-ASBT in cholangiocytes and ileocytes was regulated by bile acid flux. METHODS: Expression of ASBT and t-ASBT message and protein in cholangiocytes and ileocytes isolated from pairfed rats given control (C) and 1% taurocholate (TCA) or 5% cholestyramine (CY) enriched diets, were assessed by both quantitative RNase protection assays and quantitative immunoblotting. The data obtained from each of the control groups were pooled to reflect the changes observed following TCA and CY treatments with respect to the control diets.Cholangiocyte taurocholate uptake was determined using a novel microperfusion technique on intrahepatic bile duct units (IBDUs) derived from C, TCA and CY fed rats.RESULTS: In cholangiocytes, both ASBT and t-ASBT message RNA and protein were significantly decreased in response to TCA feeding compared to C diet. In contrast,message and protein of both bile acid transporters significantly increased following CY feeding compared to C diet. In the ileum, TCA feeding significantly up-regulated both ASBT and t-ASBT message and protein compared to C diet, while CY feeding significantly down-regulated message and protein of both bile acid transporters compared to C diet. As anticipated from alterations in cholangiocyte ASBT expression, the uptake of

  20. 谷氨酸脱羧酶抗体在2型糖尿病患者中的检出率及分布特征%Analysis of the Detection Rate and Distrubution Feature of Glutamic Acid Decarboxylase Antibodies in Patients with Type 2 Diabetes Mellitus

    Institute of Scientific and Technical Information of China (English)

    张利方; 刘莹; 石莉萍; 汪薇

    2013-01-01

    Objective: To explore the change of detection rate and distribution feature of glutamic acid decarboxylase antibody (GAD-Ab) in patients with type 2 diabetes mellitus (T2DM). Method: To detect the positive rate of GAD-Ab using EL1SA method in 1970 patients with T2DM and its distribution in different sex, age, course of disease and body mass index (BM1). Fasting, postprandial insulin 2H (FINS, 2hLNS) and fasting, postprandial 2h C peptide (FCP, 2hCP) level were detected by electro-chemiluminescence in GAD-Ab positive and negative patients and compared with the healthy people. Results: 126 cases were GAD-Ab positive among the 1970 patients with T2DM and the total positive rate was 6. 39%. GAD-Ab was mainly distributed in patients during the 30 ~49 years old (P0.05).GAD-Ab阳性组T2DM FINS、2hINS、FCP和2hCP均低于GAD-Ab阴性组和健康对照组(P<0.05).结论:GAD-Ab检测有助于临床对T2DM患者胰岛素功能变化进行评价.

  1. Structural Basis for Putrescine Activation of Human S-Adenosylmethionine Decarboxylase

    Energy Technology Data Exchange (ETDEWEB)

    Bale, Shridhar; Lopez, Maria M.; Makhatadze, George I.; Fang, Qingming; Pegg, Anthony E.; Ealick, Steven E. (Cornell); (Penn)

    2009-01-23

    Putrescine (1,4-diaminobutane) activates the autoprocessing and decarboxylation reactions of human S-adenosylmethionine decarboxylase (AdoMetDC), a critical enzyme in the polyamine biosynthetic pathway. In human AdoMetDC, putrescine binds in a buried pocket containing acidic residues Asp174, Glu178, and Glu256. The pocket is away from the active site but near the dimer interface; however, a series of hydrophilic residues connect the putrescine binding site and the active site. Mutation of these acidic residues modulates the effects of putrescine. D174N, E178Q, and E256Q mutants were expressed and dialyzed to remove putrescine and studied biochemically using X-ray crystallography, UV-CD spectroscopy, analytical ultracentrifugation, and ITC binding studies. The results show that the binding of putrescine to the wild type dimeric protein is cooperative. The D174N mutant does not bind putrescine, and the E178Q and E256Q mutants bind putrescine weakly with no cooperativity. The crystal structure of the mutants with and without putrescine and their complexes with S-adenosylmethionine methyl ester were obtained. Binding of putrescine results in a reorganization of four aromatic residues (Phe285, Phe315, Tyr318, and Phe320) and a conformational change in the loop 312-320. The loop shields putrescine from the external solvent, enhancing its electrostatic and hydrogen bonding effects. The E256Q mutant with putrescine added shows an alternate conformation of His243, Glu11, Lys80, and Ser229, the residues that link the active site and the putrescine binding site, suggesting that putrescine activates the enzyme through electrostatic effects and acts as a switch to correctly orient key catalytic residues.

  2. Hepatic bile acids and bile acid-related gene expression in pregnant and lactating rats

    Directory of Open Access Journals (Sweden)

    Qiong N. Zhu

    2013-08-01

    Full Text Available Background. Significant physiological changes occur during pregnancy and lactation. Intrahepatic cholestasis of pregnancy (ICP is a liver disease closely related to disruption of bile acid homeostasis. The objective of this study was to examine the regulation of bile acid synthesis and transport in normal pregnant and lactating rats.Materials and Methods. Livers from timed pregnant SD rats were collected on gestational days (GD 10, 14 and 19, and postnatal days (PND 1, 7, 14 and 21. Total bile acids were determined by the enzymatic method, total RNA was isolated and subjected to real time RT-PCR analysis. Liver protein was extracted for western-blot analysis.Results. Under physiological conditions hepatic bile acids were not elevated during pregnancy but increased during lactation in rats. Bile acid synthesis rate-limiting enzyme Cyp7a1 was unchanged on gestational days, but increased on PND14 and 21 at mRNA and protein levels. Expression of Cyp8b1, Cyp27a1 and Cyp7b1 was also higher during lactation. The mRNA levels of small heterodimer partner (SHP and protein levels of farnesoid X receptor (FXR were increased during pregnancy and lactation. Bile acid transporters Ntcp, Bsep, Mrp3 and Mrp4 were lower at gestation, but increased during lactation. Hepatic Oatp transporters were decreased during pregnancy and lactation.Conclusion. Hepatic bile acid homeostasis is maintained during normal pregnancy in rats, probably through the FXR-SHP regulation. The expression of bile acid synthesis genes and liver bile acid accumulation were increased during lactation, together with increased expression of bile acid efflux transporter Bsep, Mrp3 and Mrp4.

  3. Perturbation of the Monomer-Monomer Interfaces of the Benzoylformate Decarboxylase Tetramer

    Energy Technology Data Exchange (ETDEWEB)

    Andrews, Forest H.; Rogers, Megan P.; Paul, Lake N.; McLeish, Michael J. [IUPUI; (Purdue)

    2014-08-14

    The X-ray structure of benzoylformate decarboxylase (BFDC) from Pseudomonas putida ATCC 12633 shows it to be a tetramer. This was believed to be typical of all thiamin diphosphate-dependent decarboxylases until recently when the structure of KdcA, a branched-chain 2-keto acid decarboxylase from Lactococcus lactis, showed it to be a homodimer. This lent credence to earlier unfolding experiments on pyruvate decarboxylase from Saccharomyces cerevisiae that indicated that it might be active as a dimer. To investigate this possibility in BFDC, we sought to shift the equilibrium toward dimer formation. Point mutations were made in the noncatalytic monomer–monomer interfaces, but these had a minimal effect on both tetramer formation and catalytic activity. Subsequently, the R141E/Y288A/A306F variant was shown by analytical ultracentrifugation to be partially dimeric. It was also found to be catalytically inactive. Further experiments revealed that just two mutations, R141E and A306F, were sufficient to markedly alter the dimer–tetramer equilibrium and to provide an ~450-fold decrease in kcat. Equilibrium denaturation studies suggested that the residual activity was possibly due to the presence of residual tetramer. The structures of the R141E and A306F variants, determined to <1.5 Å resolution, hinted that disruption of the monomer interfaces will be accompanied by movement of a loop containing Leu109 and Leu110. As these residues contribute to the hydrophobicity of the active site and the correct positioning of the substrate, it seems that tetramer formation may well be critical to the catalytic activity of BFDC.

  4. Salicylic acid enhances Staphylococcus aureus extracellular adhesin protein expression.

    Science.gov (United States)

    Alvarez, Lucía P; Barbagelata, María S; Cheung, Ambrose L; Sordelli, Daniel O; Buzzola, Fernanda R

    2011-11-01

    One of the virulence factors required by Staphylococcus aureus at the early stages of infection is Eap, a secreted adhesin that binds many host proteins and is upregulated by the two-component regulatory system saeRS. The S. aureus Newman strain harbors a mutation in saeS that is thought to be responsible for the high level of Eap expression in this strain. This study was designed to ascertain whether salicylic acid (SAL) affects the expression of Eap and the internalization of S. aureus into epithelial cells. The strain Newman treated with SAL exhibited increased levels of eap transcription and protein expression. Furthermore, SAL treatment increased the eap promoter activity. SAL treatment enhanced Eap expression in the Newman and in other S. aureus strains that do not carry the mutation in saeS. Internalization of S. aureus eap and sae mutants into the MAC-T epithelial cells was significantly decreased compared with the wild-type counterparts. In conclusion, we demonstrated that a low concentration of SAL increased S. aureus Eap expression possibly due to enhancement of sae. SAL may create the conditions for S. aureus persistence in the host, not only by decreasing the capsular polysaccharide expression as shown before, but also by enhancing Eap expression.

  5. Characterization of a Novel Putative S-Adenosylmethionine Decarboxylase-Like Protein from Leishmania donovani.

    Directory of Open Access Journals (Sweden)

    Saurabh Pratap Singh

    Full Text Available In addition to the S-adenosylmethionine decarboxylase (AD present in all organisms, trypanosomatids including Leishmania spp. possess an additional copy, annotated as the putative S-adenosylmethionine decarboxylase-like proenzyme (ADL. Phylogenetic analysis confirms that ADL is unique to trypanosomatids and has several unique features such as lack of autocatalytic cleavage and a distinct evolutionary lineage, even from trypanosomatid ADs. In Trypanosoma ADL was found to be enzymaticaly dead but plays an essential regulatory role by forming a heterodimer complex with AD. However, no structural or functional information is available about ADL from Leishmania spp. Here, in this study, we report the cloning, expression, purification, structural and functional characterization of Leishmania donovani (L. donovani ADL using biophysical, biochemical and computational techniques. Biophysical studies show that, L. donovani ADL binds S-adenosylmethionine (SAM and putrescine which are natural substrates of AD. Computational modeling and docking studies showed that in comparison to the ADs of other organisms including human, residues involved in putrescine binding are partially conserved while the SAM binding residues are significantly different. In silico protein-protein interaction study reveals that L. donovani ADL can interact with AD. These results indicate that L. donovani ADL posses a novel substrate binding property and may play an essential role in polyamine biosynthesis with a different mode of function from known proteins of the S-adenosylmethionine decarboxylase super family.

  6. Pyruvate decarboxylases from the petite-negative yeast Saccharomyces kluyveri

    DEFF Research Database (Denmark)

    Møller, Kasper; Langkjær, Rikke Breinhold; Nielsen, Jens;

    2004-01-01

    Saccharomyces kluyveri is a petite-negative yeast, which is less prone to form ethanol under aerobic conditions than is S. cerevisiae. The first reaction on the route from pyruvate to ethanol is catalysed by pyruvate decarboxylase, and the differences observed between S. kluyveri and S. cerevisiae...... was controlled by variations in the amount of mRNA. The mRNA level and the pyruvate decarboxylase activity responded to anaerobiosis and growth on different carbon sources in essentially the same fashion as in S. cerevisiae. This indicates that the difference in ethanol formation between these two yeasts...... is not due to differences in the regulation of pyruvate decarboxylase(s), but rather to differences in the regulation of the TCA cycle and the respiratory machinery. However, the PDC genes of Saccharomyces/Kluyveromyces yeasts differ in their genetic organization and phylogenetic origin. While S. cerevisiae...

  7. Keto-isovalerate decarboxylase enzymes and methods of use thereof

    Science.gov (United States)

    McElvain, Jessica; O'Keefe, Daniel P.; Paul, Brian James; Payne, Mark S.; Rothman, Steven Cary; He, Hongxian

    2016-01-19

    Provided herein are polypeptides and polynucleotides encoding such polypeptides which have ketoisovalerate decarboxylase activity. Also provided are recombinant host cells comprising such polypeptides and polynucleotides and methods of use thereof.

  8. The krebs cycle enzyme α-ketoglutarate decarboxylase is an essential glycosomal protein in bloodstream African trypanosomes.

    Science.gov (United States)

    Sykes, Steven; Szempruch, Anthony; Hajduk, Stephen

    2015-03-01

    α-Ketoglutarate decarboxylase (α-KDE1) is a Krebs cycle enzyme found in the mitochondrion of the procyclic form (PF) of Trypanosoma brucei. The bloodstream form (BF) of T. brucei lacks a functional Krebs cycle and relies exclusively on glycolysis for ATP production. Despite the lack of a functional Krebs cycle, α-KDE1 was expressed in BF T. brucei and RNA interference knockdown of α-KDE1 mRNA resulted in rapid growth arrest and killing. Cell death was preceded by progressive swelling of the flagellar pocket as a consequence of recruitment of both flagellar and plasma membranes into the pocket. BF T. brucei expressing an epitope-tagged copy of α-KDE1 showed localization to glycosomes and not the mitochondrion. We used a cell line transfected with a reporter construct containing the N-terminal sequence of α-KDE1 fused to green fluorescent protein to examine the requirements for glycosome targeting. We found that the N-terminal 18 amino acids of α-KDE1 contain overlapping mitochondrion- and peroxisome-targeting sequences and are sufficient to direct localization to the glycosome in BF T. brucei. These results suggest that α-KDE1 has a novel moonlighting function outside the mitochondrion in BF T. brucei.

  9. Expression of retinoic acid receptors in human endometrial carcinoma.

    Science.gov (United States)

    Tanabe, Kojiro; Utsunomiya, Hiroki; Tamura, Mitsutoshi; Niikura, Hitoshi; Takano, Tadao; Yoshinaga, Kohsuke; Nagase, Satoru; Suzuki, Takashi; Ito, Kiyoshi; Matsumoto, Mitsuyo; Hayashi, Shin-ichi; Yaegashi, Nobuo

    2008-02-01

    The retinoids (vitamin A and its biologically active derivatives) are essential for the health and survival of the individual. Several studies have reported a strong rationale for the use of retinoids in cancer treatment and chemoprevention. It has been discovered that expression of retinoic acid receptor (RAR) beta is frequently silenced in epithelial carcinogenesis, which has led to the hypothesis that RAR beta could act as a tumor suppressor. However, the status of RAR beta in human endometrial carcinoma has not been examined. In the present study, we initially studied the effects of retinoic acid on cell proliferation and the expression of RAR alpha, RAR beta, and RAR gamma using AM580 (a RAR-specific agonist) in the Ishikawa endometrial cancer cell line. We also examined the expression of RAR in human eutopic endometrium (30 cases), endometrial hyperplasia (28 cases), and endometrial carcinoma (103 cases) using immunohistochemistry. Finally, we correlated these findings with the clinicopathological parameters. In vitro, cell growth was inhibited and RAR beta and RAR gamma mRNA was significantly induced by AM580, compared with vehicle controls, whereas RAR alpha mRNA was significantly attenuated by AM580, compared with vehicle. RAR beta was detected predominantly in endometrial hyperplasia, compared with endometrial carcinoma. No statistically significant correlation was obtained between the expression of any other RAR subtypes and clinicopathological parameters in human endometrial carcinoma. The results of our study demonstrate that AM580 inhibits cell growth and induces RAR beta mRNA expression in the Ishikawa cell line, and the expression level of RAR beta in endometrial carcinoma is significantly lower than that in endometrial hyperplasia. AM580 might therefore be considered as a potential treatment for endometrial carcinoma.

  10. Ornithine decarboxylase antizyme inhibitor 2 regulates intracellular vesicle trafficking

    Energy Technology Data Exchange (ETDEWEB)

    Kanerva, Kristiina; Maekitie, Laura T. [Department of Pathology, Haartman Institute, University of Helsinki, Helsinki (Finland); Baeck, Nils [Department of Anatomy, Institute of Biomedicine, University of Helsinki, Helsinki (Finland); Andersson, Leif C., E-mail: leif.andersson@helsinki.fi [Department of Pathology, Haartman Institute, University of Helsinki, Helsinki (Finland); HUSLAB, Helsinki (Finland); Department of Oncology and Pathology, Karolinska Institutet, Stockholm (Sweden)

    2010-07-01

    Antizyme inhibitor 1 (AZIN1) and 2 (AZIN2) are proteins that activate ornithine decarboxylase (ODC), the key enzyme of polyamine biosynthesis. Both AZINs release ODC from its inactive complex with antizyme (AZ), leading to formation of the catalytically active ODC. The ubiquitously expressed AZIN1 is involved in cell proliferation and transformation whereas the role of the recently found AZIN2 in cellular functions is unknown. Here we report the intracellular localization of AZIN2 and present novel evidence indicating that it acts as a regulator of vesicle trafficking. We used immunostaining to demonstrate that both endogenous and FLAG-tagged AZIN2 localize to post-Golgi vesicles of the secretory pathway. Immuno-electron microscopy revealed that the vesicles associate mainly with the trans-Golgi network (TGN). RNAi-mediated knockdown of AZIN2 or depletion of cellular polyamines caused selective fragmentation of the TGN and retarded the exocytotic release of vesicular stomatitis virus glycoprotein. Exogenous addition of polyamines normalized the morphological changes and reversed the inhibition of protein secretion. Our findings demonstrate that AZIN2 regulates the transport of secretory vesicles by locally activating ODC and polyamine biosynthesis.

  11. Glutamate Decarboxylase 1 Overexpression as a Poor Prognostic Factor in Patients with Nasopharyngeal Carcinoma

    Science.gov (United States)

    Lee, Yi-Ying; Chao, Tung-Bo; Sheu, Ming-Jen; Tian, Yu-Feng; Chen, Tzu-Ju; Lee, Sung-Wei; He, Hong-Lin; Chang, I-Wei; Hsing, Chung-Hsi; Lin, Ching-Yih; Li, Chien-Feng

    2016-01-01

    Background: Glutamate decarboxylase 1 (GAD1) which serves as a rate-limiting enzyme involving in the production of γ-aminobutyric acid (GABA), exists in the GABAergic neurons in the central nervous system (CNS). Little is known about the relevance of GAD1 to nasopharyngeal carcinoma (NPC). Through data mining on a data set derived from a published transcriptome database, this study first identified GAD1 as a differentially upregulated gene in NPC. We aimed to evaluate GAD1 expression and its prognostic effect on patients with early and locoregionally advanced NPC. Methods: We evaluated GAD1 immunohistochemistry and performed an H-score analysis on biopsy specimens from 124 patients with nonmetastasized NPC receiving treatment. GAD1 overexpression was defined as an H score higher than the median value. The findings of such an analysis are correlated with clinicopathological behaviors and survival rates, namely disease-specific survival (DSS), distant-metastasis-free survival (DMeFS), and local recurrence-free survival (LRFS) rates. Results: GAD1 overexpression was significantly associated with an increase in the primary tumor status (p < 0.001) and American Joint Committee on Cancer (AJCC) stages III-IV (p = 0.002) and was a univariate predictor of adverse outcomes of DSS (p = 0.002), DMeFS (p < 0.0001), and LRFS (p = 0.001). In the multivariate comparison, in addition to advanced AJCC stages III-IV, GAD1 overexpression remained an independent prognosticator of short DSS (p = 0.004, hazard ratio = 2.234), DMeFS (p < 0.001, hazard ratio = 4.218), and LRFS (p = 0.013, hazard ratio = 2.441) rates. Conclusions: Our data reveal that GAD1 overexpression was correlated with advanced disease status and may thus be a critical prognostic indicator of poor outcomes in NPC and a potential therapeutic target to facilitate the development of effective treatment modalities. PMID:27698909

  12. A porphodimethene chemical inhibitor of uroporphyrinogen decarboxylase.

    Directory of Open Access Journals (Sweden)

    Kenneth W Yip

    Full Text Available Uroporphyrinogen decarboxylase (UROD catalyzes the conversion of uroporphyrinogen to coproporphyrinogen during heme biosynthesis. This enzyme was recently identified as a potential anticancer target; its inhibition leads to an increase in reactive oxygen species, likely mediated by the Fenton reaction, thereby decreasing cancer cell viability and working in cooperation with radiation and/or cisplatin. Because there is no known chemical UROD inhibitor suitable for use in translational studies, we aimed to design, synthesize, and characterize such a compound. Initial in silico-based design and docking analyses identified a potential porphyrin analogue that was subsequently synthesized. This species, a porphodimethene (named PI-16, was found to inhibit UROD in an enzymatic assay (IC50 = 9.9 µM, but did not affect porphobilinogen deaminase (at 62.5 µM, thereby exhibiting specificity. In cellular assays, PI-16 reduced the viability of FaDu and ME-180 cancer cells with half maximal effective concentrations of 22.7 µM and 26.9 µM, respectively, and only minimally affected normal oral epithelial (NOE cells. PI-16 also combined effectively with radiation and cisplatin, with potent synergy being observed in the case of cisplatin in FaDu cells (Chou-Talalay combination index <1. This work presents the first known synthetic UROD inhibitor, and sets the foundation for the design, synthesis, and characterization of higher affinity and more effective UROD inhibitors.

  13. 一种谷氨酸脱羧酶65相关肽融合蛋白的制备及其治疗1型糖尿病的药效研究%Genetic Fusion of Glutamic Acid Decarboxylase 65 Derived Peptides to the B-Subunit of Cholera Toxin and Its Retardation Effect of Diabetes in NOD Mice

    Institute of Scientific and Technical Information of China (English)

    王华倩; 张会勇; 杨洁; 鲁勇; 李泰明; 金亮; 曹荣月; 刘景晶

    2009-01-01

    使用基因工程方法构建了霍乱毒素B亚单位(Cholera toxin B subunit,CTB)与谷氨酸脱羧酶65(glutamic acid decarboxylase 65,GAD65)串联三肽GADⅢ(包括p217-236,p524-538,p290-306)合基因CTB-GADⅢ.将融合基因克隆到大肠杆菌表达载体pET-28a中,获得的重组质粒转化大肠杆菌BL21(DE3).重组菌株经乳糖诱导后,其表达产物经过15%SDS-PAGE分析表明该菌株可以以包涵体形式表达融合蛋白,Mr约为17.6 k.含有CTB-GADⅢ重组蛋白的包涵体经过变性、复性、纯化后,可以得到五聚体结构的CTB-GADⅢ.神经节苷脂GM1(monosialoganglioside)结合实验表明重组CTB-GADⅢ蛋白可以与GM1特异性结合,表明该融合蛋白保持了CTB形成五聚体的生物活性.使用该重组蛋白在NOD小鼠周龄、10周龄和12周龄时滴鼻免疫小鼠共3次,可以显著降低小鼠的发病率,达到治疗1型糖尿病的作用.

  14. Endogenous Inactivators of Arginase, l-Arginine Decarboxylase, and Agmatine Amidinohydrolase in Evernia prunastri Thallus 1

    Science.gov (United States)

    Legaz, María Estrella; Vicente, Carlos

    1983-01-01

    Arginase (EC 3.5.3.1), l-arginine decarboxylase (EC 4.1.1.19), and agmatine amidinohydrolase (EC 3.5.3.11) activities spontaneously decay in Evernia prunastri thalli incubated on 40 millimolar l-arginine used as inducer of the three enzymes if dithiothreitol is not added to the media. Lichen thalli accumulate both chloroatranorin and evernic acid in parallel to the loss of activity. These substances behave as inactivators of the enzymes at a range of concentrations between 2 and 20 micromolar, whereas several concentrations of dithiothreitol reverse, to some extent, the in vitro inactivation. PMID:16662821

  15. Endogenous Inactivators of Arginase, l-Arginine Decarboxylase, and Agmatine Amidinohydrolase in Evernia prunastri Thallus.

    Science.gov (United States)

    Legaz, M E; Vicente, C

    1983-02-01

    Arginase (EC 3.5.3.1), l-arginine decarboxylase (EC 4.1.1.19), and agmatine amidinohydrolase (EC 3.5.3.11) activities spontaneously decay in Evernia prunastri thalli incubated on 40 millimolar l-arginine used as inducer of the three enzymes if dithiothreitol is not added to the media. Lichen thalli accumulate both chloroatranorin and evernic acid in parallel to the loss of activity. These substances behave as inactivators of the enzymes at a range of concentrations between 2 and 20 micromolar, whereas several concentrations of dithiothreitol reverse, to some extent, the in vitro inactivation.

  16. 半胱亚磺酸脱羧酶在成年小鼠副性腺器官中的表达%Expression of Cysteine Sulfinate Decarboxylase in Male Accessory Organs of Adult Mice

    Institute of Scientific and Technical Information of China (English)

    范晶晶; 庞立义

    2012-01-01

    We conducted semi-quantitative reverse transcription polymerase chain reaction(RT-PCR),western blott and immunohistochemical analysis in order to examine CSD mRNA and protein expression in the accessory organs of male mice.The results show that CSD is expressed both at the mRNA and protein levels in the organs.Immunohistochemical analysis reveals that CSD is expressed in the tall columnar cells of the seminal vesicle,the glandular epithelium of the bulbourethral gland,and the epithelial cells of the prostate gland.These results suggest that male accessory organs have the function to produce taurine through the CSD pathway.%采用RT-PCR、Western blot、免疫组织化学方法检测了CSD在小鼠副性腺器官中mRNA和蛋白水平的表达。结果显示,CSD在小鼠副性腺器官中都有mRNA和蛋白水平的表达。CSD主要定位于精囊腺的高柱状上皮细胞、前列腺的腺上皮细胞和尿道球腺的腺上皮细胞中。结果表明雄性副性腺器官可以通过CSD合成通路参与牛磺酸的合成。

  17. Expression of Clostridium acetobutylicum ATCC 824 Genes in Escherichia coli for Acetone Production and Acetate Detoxification

    OpenAIRE

    Bermejo, Lourdes L.; Welker, Neil E.; Papoutsakis, Eleftherios T.

    1998-01-01

    A synthetic acetone operon (ace4) composed of four Clostridium acetobutylicum ATCC 824 genes (adc, ctfAB, and thl, coding for the acetoacetate decarboxylase, coenzyme A transferase, and thiolase, respectively) under the control of the thl promoter was constructed and was introduced into Escherichia coli on vector pACT. Acetone production demonstrated that ace4 is expressed in E. coli and resulted in the reduction of acetic acid levels in the fermentation broth. Since different E. coli strains...

  18. Conformational stabilization of rat s-adenosylmethionine decarboxylase by putrescine.

    Science.gov (United States)

    Wada, Makiko; Shirahata, Akira

    2010-01-01

    The activity and processing of mammalian S-adenosylmethionine decarboxylase (AdoMetDC) is stimulated by putrescine. To obtain new insights into the mechanism through which putrescine stimulates AdoMetDC, we investigated conformational changes in rat prostate AdoMetDC in the presence or absence of putrescine. We examined the reactivity of purified rat prostate AdoMetDC to the SH-reagent iodoacetic acid (IAA) and its susceptibility to proteolysis in the presence or absence of putrescine using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). The activity of AdoMetDC treated with IAA in the absence of putrescine was reduced, but about 80% of its activity remained after treatment with IAA in the presence of putrescine. In the presence of putrescine, IAA incorporation was 1.9 mol IAA/mol of AdoMetDC α-subunit, while there was no incorporation of IAA in the β-subunit of AdoMetDC. In the absence of putrescine, 5.0 mol of IAA/mol of α-subunit and 0.9 mol of IAA/mol of β-subunit were incorporated. Only Cys292 and Cys310 were carboxymethylated by IAA in the presence of putrescine. In contrast, in the absence of putrescine all cysteines were carboxymethylated by IAA. In addition, putrescine slowed the rate of AdoMetDC degradation by trypsin. These results demonstrate that the conformation of AdoMetDC purified from rat prostate is stabilized by putrescine.

  19. [Molecular cloning and characterization of S-adenosyl-L-methionine decarboxylase gene (DoSAMDC1) in Dendrobium officinale].

    Science.gov (United States)

    Zhao, Ming-Ming; Zhang, Gang; Zhang, Da-Wei; Guo, Shun-Xing

    2013-06-01

    S-Adenosyl-L-methionine decarboxylase (SAMDC) is a key enzyme in the polyamines biosynthesis, thus is essential for basic physiological and biochemical processes in plant. In the present study, a full length cDNA of DoSAMDC1 gene was obtained from symbiotic germinated seeds of an endangered medicinal orchid species Dendrobium officinale, using the rapid amplification of cDNA ends (RACE)-PCR technique for the first time. The full length cDNA was 1 979 bp, with three open reading frames, i.e. tiny-uORF, small-uORF and main ORF (mORF). The mORF was deduced to encode a 368 amino acid (aa) protein with a molecular mass of 40.7 kD and a theoretical isoelectric point of 5.2. The deduced DoSAMDC1 protein, without signal peptide, had two highly conserved function domains (proenzyme cleavage site and PEST domain) and a 22-aa transmembrane domain (89-110). Multiple sequence alignments and phylogenetic relationship analyses revealed DoSAMDC1 had a higher level of sequence similarity to monocot SAMDCs than those of dicot. Expression patterns using qRT-PCR analyses showed that DoSAMDC1 transcripts were expressed constitutively without significant change in the five tissues (not infected with fungi). While in the symbiotic germinated seeds, the expression level was enhanced by 2.74 fold over that in the none-germinated seeds, indicating possible involvement of the gene in symbiotic seed germination of D. officinale.

  20. Identification of γ-aminobutyric Acid producing Enterococcus faecium and Characterization of Its Glutamate Decarboxylase%产γ-氨基丁酸屎肠球菌的鉴定及其谷氨酸脱羧酶酶学性质

    Institute of Scientific and Technical Information of China (English)

    李云; 杨胜远; 杨韵晴; 黄荣城; 陈郁娜; 刘祥流

    2010-01-01

    目的: 鉴定1株产γ氨基丁酸(γ-aminobutyric acid,GABA)的乳酸菌HS3,并研究了其谷氨酸脱羧酶(Glutamate decarboxylase,GAD)粗酶酶学性质.方法:根据形态培养特征、生理生化特征和16S rDNA序列比对及系统发育分析对菌株HS3进行了鉴定.采用菌体细胞破碎后的粗酶液,研究了温度、pH和金属离子对酶活的影响.结果:菌株HS3的形态培养和生理生化特征符合肠球菌属(Enterococcus)特征,其16S rDNA序列与Enterococcus faecium(EU717962)16S rDNA序列同源性达99%,鉴定菌株HS3为屎肠球菌(Enterococcus faecium),菌株HS3 GAD最适作用温度为40 ℃,最适作用pH4.5.酶的热稳定较好,50℃处理4h,在pH3.5~6.0酶活基本稳定.Ca~(2+)对酶有激活作用,5mmol/L和50mmol/L浓度酶活分别提高了37.41%和17.43%.Ba~(2+)和Zn~(2+)在5mmol/L浓度时激活作用明显,而Mg~(2+)在5mmol/L浓度激活作用较好.结论:菌株HS3的GAD活力较高,稳定性较好,为生物合成GABA提供了新的微生物菌种资源.

  1. Complex modulation of androgen responsive gene expression by methoxyacetic acid

    Directory of Open Access Journals (Sweden)

    Stanley Kerri A

    2011-03-01

    Full Text Available Abstract Background Optimal androgen signaling is critical for testicular development and spermatogenesis. Methoxyacetic acid (MAA, the primary active metabolite of the industrial chemical ethylene glycol monomethyl ether, disrupts spermatogenesis and causes testicular atrophy. Transcriptional trans-activation studies have indicated that MAA can enhance androgen receptor activity, however, whether MAA actually impacts the expression of androgen-responsive genes in vivo, and which genes might be affected is not known. Methods A mouse TM3 Leydig cell line that stably expresses androgen receptor (TM3-AR was prepared and analyzed by transcriptional profiling to identify target gene interactions between MAA and testosterone on a global scale. Results MAA is shown to have widespread effects on androgen-responsive genes, affecting processes ranging from apoptosis to ion transport, cell adhesion, phosphorylation and transcription, with MAA able to enhance, as well as antagonize, androgenic responses. Moreover, testosterone is shown to exert both positive and negative effects on MAA gene responses. Motif analysis indicated that binding sites for FOX, HOX, LEF/TCF, STAT5 and MEF2 family transcription factors are among the most highly enriched in genes regulated by testosterone and MAA. Notably, 65 FOXO targets were repressed by testosterone or showed repression enhanced by MAA with testosterone; these include 16 genes associated with developmental processes, six of which are Hox genes. Conclusions These findings highlight the complex interactions between testosterone and MAA, and provide insight into the effects of MAA exposure on androgen-dependent processes in a Leydig cell model.

  2. A dopa decarboxylase modulating the immune response of scallop Chlamys farreri.

    Directory of Open Access Journals (Sweden)

    Zhi Zhou

    Full Text Available BACKGROUND: Dopa decarboxylase (DDC is a pyridoxal 5-phosphate (PLP-dependent enzyme that catalyzes the decarboxylation of L-Dopa to dopamine, and involved in complex neuroendocrine-immune regulatory network. The function for DDC in the immunomodulation remains unclear in invertebrate. METHODOLOGY: The full-length cDNA encoding DDC (designated CfDDC was cloned from mollusc scallop Chlamys farreri. It contained an open reading frame encoding a polypeptide of 560 amino acids. The CfDDC mRNA transcripts could be detected in all the tested tissues, including the immune tissues haemocytes and hepatopancreas. After scallops were treated with LPS stimulation, the mRNA expression level of CfDDC in haemocytes increased significantly (5.5-fold, P<0.05 at 3 h and reached the peak at 12 h (9.8-fold, P<0.05, and then recovered to the baseline level. The recombinant protein of CfDDC (rCfDDC was expressed in Escherichia coli BL21 (DE3-Transetta, and 1 mg rCfDDC could catalyze the production of 1.651±0.22 ng dopamine within 1 h in vitro. When the haemocytes were incubated with rCfDDC-coated agarose beads, the haemocyte encapsulation to the beads was increased significantly from 70% at 6 h to 93% at 24 h in vitro in comparison with that in the control (23% at 6 h to 25% at 24 h, and the increased haemocyte encapsulation was repressed by the addition of rCfDDC antibody (which is acquired via immunization 6-week old rats with rCfDDC. After the injection of DDC inhibitor methyldopa, the ROS level in haemocytes of scallops was decreased significantly to 0.41-fold (P<0.05 of blank group at 12 h and 0.47-fold (P<0.05 at 24 h, respectively. CONCLUSIONS: These results collectively suggested that CfDDC, as a homologue of DDC in scallop, modulated the immune responses such as haemocytes encapsulation as well as the ROS level through its catalytic activity, functioning as an indispensable immunomodulating enzyme in the neuroendocrine-immune regulatory network of mollusc.

  3. Fish Oil Supplementation and Fatty Acid Synthase Expression in the Prostate: A Randomized Controlled Trial

    Science.gov (United States)

    2008-03-01

    expression and fatty acid synthesis. Research in normal cells has demonstrated that dietary supplementation with polyunsaturated fatty acids ( PUFA ...particularly omega -3 fatty acids , inhibits SREBP-1 activation, resulting in a decreased transcription of FAS. 15. SUBJECT TERMS Prostate Cancer...Lipid Medtabolism, Clinical Trial; Omega -3 Fatty Acids 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES 19a. NAME

  4. Cysteine dioxygenase and cysteine sulfinate decarboxylase genes of the deep-sea mussel Bathymodiolus septemdierum: possible involvement in hypotaurine synthesis and adaptation to hydrogen sulfide.

    Science.gov (United States)

    Nagasaki, Toshihiro; Hongo, Yuki; Koito, Tomoko; Nakamura-Kusakabe, Ikumi; Shimamura, Shigeru; Takaki, Yoshihiro; Yoshida, Takao; Maruyama, Tadashi; Inoue, Koji

    2015-03-01

    It has been suggested that invertebrates inhabiting deep-sea hydrothermal vent areas use the sulfinic acid hypotaurine, a precursor of taurine, to protect against the toxicity of hydrogen sulfide contained in the seawater from the vent. In this protective system, hypotaurine is accumulated in the gill, the primary site of sulfide exposure. However, the pathway for hypotaurine synthesis in mollusks has not been identified. In this study, we screened for the mRNAs of enzymes involved in hypotaurine synthesis in the deep-sea mussel Bathymodiolus septemdierum and cloned cDNAs encoding cysteine dioxygenase and cysteine sulfinate decarboxylase. As mRNAs encoding cysteamine dioxygenase and cysteine lyase were not detected, the cysteine sulfinate pathway is suggested to be the major pathway of hypotaurine and taurine synthesis. The two genes were found to be expressed in all the tissues examined, but the gill exhibited the highest expression. The mRNA level in the gill was not significantly changed by exposure to sulfides or thiosulfate. These results suggests that the gill of B. septemdierum maintains high levels of expression of the two genes regardless of ambient sulfide level and accumulates hypotaurine continuously to protect against sudden exposure to high level of sulfide.

  5. Impact of methoxyacetic acid on mouse Leydig cell gene expression

    Directory of Open Access Journals (Sweden)

    Waxman David J

    2010-06-01

    Full Text Available Abstract Background Methoxyacetic acid (MAA is the active metabolite of the widely used industrial chemical ethylene glycol monomethyl ether, which is associated with various developmental and reproductive toxicities, including neural toxicity, blood and immune disorders, limb degeneration and testicular toxicity. Testicular toxicity is caused by degeneration of germ cells in association with changes in gene expression in both germ cells and Sertoli cells of the testis. This study investigates the impact of MAA on gene expression in testicular Leydig cells, which play a critical role in germ cell survival and male reproductive function. Methods Cultured mouse TM3 Leydig cells were treated with MAA for 3, 8, and 24 h and changes in gene expression were monitored by genome-wide transcriptional profiling. Results A total of 3,912 MAA-responsive genes were identified. Ingenuity Pathway analysis identified reproductive system disease, inflammatory disease and connective tissue disorder as the top biological functions affected by MAA. The MAA-responsive genes were classified into 1,366 early responders, 1,387 mid-responders, and 1,138 late responders, based on the time required for MAA to elicit a response. Analysis of enriched functional clusters for each subgroup identified 106 MAA early response genes involved in transcription regulation, including 32 genes associated with developmental processes. 60 DNA-binding proteins responded to MAA rapidly but transiently, and may contribute to the downstream effects of MAA seen for many mid and late response genes. Genes within the phosphatidylinositol/phospholipase C/calcium signaling pathway, whose activity is required for potentiation of nuclear receptor signaling by MAA, were also enriched in the set of early MAA response genes. In contrast, many of the genes responding to MAA at later time points encode membrane proteins that contribute to cell adhesion and membrane signaling. Conclusions These findings

  6. Genetics Home Reference: aromatic l-amino acid decarboxylase deficiency

    Science.gov (United States)

    ... the limbs (athetosis). They may be lacking in energy (lethargic), feed poorly, startle easily, and have sleep disturbances. People with AADC deficiency may also experience episodes called oculogyric crises that involve abnormal rotation of the eyeballs; extreme ...

  7. Glial fibrillary acidic protein isoform expression in plaque related astrogliosis in Alzheimer's disease

    NARCIS (Netherlands)

    Kamphuis, W.; Middeldorp, Jinte; Kooijman, Lieneke; Sluijs, Jacqueline A; Kooi, Evert-Jan; Moeton, Martina; Freriks, Michel; Mizee, Mark R; Hol, Elly M

    2014-01-01

    In Alzheimer's disease (AD), amyloid plaques are surrounded by reactive astrocytes with an increased expression of intermediate filaments including glial fibrillary acidic protein (GFAP). Different GFAP isoforms have been identified that are differentially expressed by specific subpopulations of ast

  8. Influence of acid and bile acid on ERK activity, PPARY expression and cell proliferation in normal human esophageal epithelial cells

    Institute of Scientific and Technical Information of China (English)

    Zhi-Ru Jiang; Jun Gong; Zhen-Ni Zhang; Zhe Qiao

    2006-01-01

    AIM: To observe the effects of acid and bile acid exposure on cell proliferation and the expression of extracellular signal-regulated protein kinase (ERK) and peroxisome proliferator-activated receptor Y (PPARy) in normal human esophageal epithelial cells in vitro.METHODS: In vitro cultured normal human esophageal epithelial cells were exposed to acidic media (pH 4.0-6.5), media containing different bile acid (250 μmol/L), media containing acid and bile acid, respectively.Cell proliferation was assessed using MTT and flow cytometry. The expressions of phosphorylated ERK1/2 and PPARy protein were determined by the immunoblotting technique.RESULTS: Acid-exposed (3 min) esophageal cells exhibited a significant increase in proliferation ratio,S phase of the cell cycle (P<0.05) and the level of phosphorylated ERK1/2 protein. When the acid-exposure period exceeded 6 min, we observed a decrease in proliferation ratio and S phase of the cell cycle, with an increased apoptosis ratio (P<0.05). Bile acid exposure (3-12 min) also produced an increase in proliferation ratio, S phase of the cell cycle (P<0.05)and phosphorylated ERK1/2 expression. On the contrary,deoxycholic acid (DCA) exposure (>20 min) decreased proliferation ratio. Compared with bile acid exposure (pH 7.4), bile acid exposure (pH 6.5, 4) significantly decreased proliferation ratio (P<0.05). There was no expression of PPARY in normal human esophageal epithelial cells.CONCLUSION: The rapid stimuli of acid or bile acid increase proliferation in normal human esophageal epithelial cells by activating the ERK pathway.

  9. Identification and molecular cloning of glutamate decarboxylase gene from Lactobacillus casei

    Directory of Open Access Journals (Sweden)

    Yasaman Tavakoli

    2015-09-01

    Full Text Available Gamma-amino butyric acid (GABA possesses several physiological functions such as neurotransmission, induction of hypotension, diuretic and tranquilizer effects. Production of GABA-enriched products by lactic acid bacteria has been a focus of different researches in recent years because of their safety and health-promoting specifities. In this study, glutamate decarboxylase (gad gene of a local strains Lactobacillus casei was identified and cloned. In order to clone the gad gene from this strain, the PCR was carried out using primers designed based on conserved regions. The PCR product was purified and ligated into PGEM-T vector. Comparison of obtained sequences shows that this fragment codes the pyridoxal 5′-phosphate binding region. This strain could possibly be used for the industrial GABA production and also for development of functional fermented foods. Gad gene manipulation can also either decrease or increase the activity of enzyme in bacteria.

  10. Increased Production of Fatty Acids and Triglycerides in Aspergillus oryzae by Enhancing Expressions of Fatty Acid Synthesis-Related Genes

    Energy Technology Data Exchange (ETDEWEB)

    Tamano, Koichi; Bruno, Kenneth S.; Karagiosis, Sue A.; Culley, David E.; Deng, Shuang; Collett, James R.; Umemura, Myco; Koike, Hideaki; Baker, Scott E.; Machida, Masa

    2013-01-01

    Microbial production of fats and oils is being developedas a means of converting biomass to biofuels. Here we investigate enhancing expression of enzymes involved in the production of fatty acids and triglycerides as a means to increase production of these compounds in Aspergillusoryzae. Examination of the A.oryzaegenome demonstrates that it contains twofatty acid synthases and several other genes that are predicted to be part of this biosynthetic pathway. We enhancedthe expressionof fatty acid synthesis-related genes by replacing their promoters with thepromoter fromthe constitutively highly expressedgene tef1. We demonstrate that by simply increasing the expression of the fatty acid synthasegenes we successfullyincreasedtheproduction of fatty acids and triglyceridesby more than two fold. Enhancement of expression of the fatty acid pathway genes ATP-citrate lyase and palmitoyl-ACP thioesteraseincreasedproductivity to a lesser extent.Increasing expression ofacetyl-CoA carboxylase caused no detectable change in fatty acid levels. Increases in message level for each gene were monitored usingquantitative real-time RT-PCR. Our data demonstrates that a simple increase in the abundance of fatty acid synthase genes can increase the detectable amount of fatty acids.

  11. Isobutanol production in engineered Saccharomyces cerevisiae by overexpression of 2-ketoisovalerate decarboxylase and valine biosynthetic enzymes.

    Science.gov (United States)

    Lee, Won-Heong; Seo, Seung-Oh; Bae, Yi-Hyun; Nan, Hong; Jin, Yong-Su; Seo, Jin-Ho

    2012-11-01

    Engineering of Saccharomyces cerevisiae to produce advanced biofuels such as isobutanol has received much attention because this yeast has a natural capacity to produce higher alcohols. In this study, construction of isobutanol production systems was attempted by overexpression of effective 2-keto acid decarboxylase (KDC) and combinatorial overexpression of valine biosynthetic enzymes in S. cerevisiae D452-2. Among the six putative KDC enzymes from various microorganisms, 2-ketoisovalerate decarboxylase (Kivd) from L. lactis subsp. lactis KACC 13877 was identified as the most suitable KDC for isobutanol production in the yeast. Isobutanol production by the engineered S. cerevisiae was assessed in micro-aerobic batch fermentations using glucose as a sole carbon source. 93 mg/L isobutanol was produced in the Kivd overexpressing strain, which corresponds to a fourfold improvement as compared with the control strain. Isobutanol production was further enhanced to 151 mg/L by additional overexpression of acetolactate synthase (Ilv2p), acetohydroxyacid reductoisomerase (Ilv5p), and dihydroxyacid dehydratase (Ilv3p) in the cytosol.

  12. Induction of amino acid transporters expression by endurance exercise in rat skeletal muscle

    Energy Technology Data Exchange (ETDEWEB)

    Murakami, Taro, E-mail: tamuraka@sgk.ac.jp; Yoshinaga, Mariko

    2013-10-04

    Highlights: •Regulation of amino acid transporter expression in working muscle remains unclear. •Expression of amino acid transporters for leucine were induced by a bout of exercise. •Requirement of leucine in muscle cells might regulate expression of its transporters. •This information is beneficial for understanding the muscle remodeling by exercise. -- Abstract: We here investigated whether an acute bout of endurance exercise would induce the expression of amino acid transporters that regulate leucine transport across plasma and lysosomal membranes in rat skeletal muscle. Rats ran on a motor-driven treadmill at a speed of 28 m/min for 90 min. Immediately after the exercise, we observed that expression of mRNAs encoding L-type amino acid transporter 1 (LAT1) and CD98 was induced in the gastrocnemius, soleus, and extensor digitorum longus (EDL) muscles. Sodium-coupled neutral amino acid transporter 2 (SNAT2) mRNA was also induced by the exercise in those three muscles. Expression of proton-assisted amino acid transporter 1 (PAT1) mRNA was slightly but not significantly induced by a single bout of exercise in soleus and EDL muscles. Exercise-induced mRNA expression of these amino acid transporters appeared to be attenuated by repeated bouts of the exercise. These results suggested that the expression of amino acid transporters for leucine may be induced in response to an increase in the requirement for this amino acid in the cells of working skeletal muscles.

  13. Monitoring Gene Expression In Vivo with Nucleic Acid Molecular Switches

    Energy Technology Data Exchange (ETDEWEB)

    David C. Ward; Patricia Bray-Ward

    2005-01-26

    The overall objectives of this project were (1) to develop allosteric ribozymes capable of acting as molecular switches for monitoring the levels of both wild-type and mutant mRNA species in living cells and whole animals and (2) to develop highly efficient reagents to deliver nucleic acid molecular switches into living cells, tissues and animals with the ultimate goal of expression profiling specific mRNAs of diagnostic or prognostic value within tumors in animals. During the past year, we have moved our laboratory to Nevada and in the moving process we have lost electronic and paper copies of prior progress reports concerning the construction and biological properties of the molecular switches. Since there was minimal progress during the last year on molecular switches, we are relying on past project reports to provide a summary of our data on this facet of the grant. Here we are summarizing the work done on the delivery reagents and their application to inducing mutations in living cells, which will include work done during the no cost extension.

  14. Activation of hepatic lipase expression by oleic acid: possible involvement of USF1.

    NARCIS (Netherlands)

    D. van Deursen (Diederik); M. van Leeuwen (Marije); D. Akdogan (Deniz); H. Adams (Hadie); H. Jansen (Hans); A.J.M. Verhoeven (Adrie)

    2009-01-01

    textabstractPolyunsaturated fatty acids affect gene expression mainly through peroxisome proliferator-activated receptors (PPARs) and sterol regulatory element binding proteins (SREBPs), but how monounsaturated fatty acids affect gene expression is poorly understood. In HepG2 cells, oleate supplemen

  15. Reduced Expression of Lipoic Acid Synthase Accelerates Diabetic Nephropathy

    OpenAIRE

    Yi, Xianwen; Xu, Longquan; Hiller, Sylvia; Kim, Hyung-Suk; Nickeleit, Volker; James, Leighton R; Maeda, Nobuyo

    2011-01-01

    Oxidative stress contributes to the pathogenesis of diabetic nephropathy. In mitochondria, lipoic acid synthase produces α-lipoic acid, an antioxidant and an essential cofactor in α-ketoacid dehydrogenase complexes, which participate in glucose oxidation and ATP generation. Administration of lipoic acid abrogates diabetic nephropathy in animal models, but whether lower production of endogenous lipoic acid promotes diabetic nephropathy is unknown. Here, we crossed mice heterozygous for lipoic ...

  16. Controlled Gene Expression Systems for Lactic Acid Bacteria : Transferable Nisin-Inducible Expression Cassettes for Lactococcus, Leuconostoc, and Lactobacillus spp.

    NARCIS (Netherlands)

    Kleerebezem, Michiel; Beerthuyzen, Marke M.; Vaughan, Elaine E.; Vos, Willem M. de; Kuipers, Oscar P.

    1997-01-01

    A transferable dual-plasmid inducible gene expression system for use in lactic acid bacteria that is based on the autoregulatory properties of the antimicrobial peptide nisin produced by Lactococcus lactis was developed. Introduction of the two plasmids allowed nisin-inducible gene expression in Lac

  17. Long-lasting c-fos and NGF mRNA expressions and loss of perikaryal parvalbumin immunoreactivity in the development of epileptogenesis after ethacrynic acid-induced seizure.

    Science.gov (United States)

    Suzukawa, J; Omori, K; Okugawa, G; Fujiseki, Y; Heizmann, C W; Inagaki, C

    1999-07-10

    A single cerebroventricular injection of ethacrynic acid (EA), a Cl(-)-ATPase inhibitor, induces generalized tonic-clonic convulsions in mice. To clarify whether such convulsive stimulus triggers a long-lasting rearrangement of the neural circuitry culminating in seizure susceptibility, we examined molecular, cellular and behavioral changes following the EA-induced seizure. The expression of immediate early gene c-fos mRNA as an index for cellular activation increased biphasically, with an early transient increase at 60 min and a late prolonged increase on the 10th to 14th day post-EA administration, most remarkably in the hippocampus and pyriform cortex. On the 14th day post-EA seizure, subconvulsive dose of kainic acid (5-17.5 mg/kg) caused severe (stage 5) seizure in 77% of the mice, with 70% mortality. In addition, the expression of nerve growth factor (NGF) also showed biphasic increases with close spatiotemporal correlation with c-fos expression. Moreover, the number of cell somata and the density of axon fibers of parvalbumin (PARV)-positive cells, a subpopulation of GABAergic interneurons, decreased in area dentata, CA1 and CA3 on the 7th and 14th day post-EA seizure. In area dentata and CA1, the density of glutamic acid decarboxylase (GAD)-positive cells also decreased on the 14th day. Thus, the transient EA-induced seizures appear to develop seizure susceptibility by causing damage of a subpopulation of inhibitory interneurons along with increases in the expression of c-fos and NGF in limbic structures.

  18. FcWRKY70, a WRKY protein of Fortunella crassifolia, functions in drought tolerance and modulates putrescine synthesis by regulating arginine decarboxylase gene.

    Science.gov (United States)

    Gong, Xiaoqing; Zhang, Jingyan; Hu, Jianbing; Wang, Wei; Wu, Hao; Zhang, Qinghua; Liu, Ji-Hong

    2015-11-01

    WRKY comprises a large family of transcription factors in plants, but most WRKY members are still poorly understood. In this study, we report functional characterization of a Group III WRKY gene (FcWRKY70) from Fortunella crassifolia. FcWRKY70 was greatly induced by drought and abscisic acid, but slightly or negligibly by salt and cold. Overexpression of FcWRKY70 in tobacco (Nicotiana nudicaulis) and lemon (Citrus lemon) conferred enhanced tolerance to dehydration and drought stresses. Transgenic tobacco and lemon exhibited higher expression levels of ADC (arginine decarboxylase), and accumulated larger amount of putrescine in comparison with wild type (WT). Treatment with D-arginine, an inhibitor of ADC, caused transgenic tobacco plants more sensitive to dehydration. Knock-down of FcWRKY70 in kumquat down-regulated ADC abundance and decreased putrescine level, accompanied by compromised dehydration tolerance. The promoter region of FcADC contained two W-box elements, which were shown to be interacted with FcWRKY70. Taken together, our data demonstrated that FcWRKY70 functions in drought tolerance by, at least partly, promoting production of putrescine via regulating ADC expression.

  19. Arginine decarboxylase as the source of putrescine for tobacco alkaloids

    Science.gov (United States)

    Tiburcio, A. F.; Galston, A. W.

    1986-01-01

    The putrescine which forms a part of nicotine and other pyrrolidine alkaloids is generally assumed to arise through the action of ornithine decarboxylase (ODC). However, we have previously noted that changes in the activity of arginine decarboxylase (ADC), an alternate source of putrescine, parallel changes in tissue alkaloids, while changes in ODC activity do not. This led us to undertake experiments to permit discrimination between ADC and ODC as enzymatic sources of putrescine destined for alkaloids. Two kinds of evidence presented here support a major role for ADC in the generation of putrescine going into alkaloids: (a) A specific 'suicide inhibitor' of ADC effectively inhibits the biosynthesis of nicotine and nornicotine in tobacco callus, while the analogous inhibitor of ODC is less effective, and (b) the flow of 14C from uniformly labelled arginine into nicotine is much more efficient than that from ornithine.

  20. Expression of fatty acid synthesis genes and fatty acid accumulation in haematococcus pluvialis under different stressors

    Directory of Open Access Journals (Sweden)

    Lei Anping

    2012-03-01

    Full Text Available Abstract Background Biofuel has been the focus of intensive global research over the past few years. The development of 4th generation biofuel production (algae-to-biofuels based on metabolic engineering of algae is still in its infancy, one of the main barriers is our lacking of understanding of microalgal growth, metabolism and biofuel production. Although fatty acid (FA biosynthesis pathway genes have been all cloned and biosynthesis pathway was built up in some higher plants, the molecular mechanism for its regulation in microalgae is far away from elucidation. Results We cloned main key genes for FA biosynthesis in Haematococcus pluvialis, a green microalga as a potential biodiesel feedstock, and investigated the correlations between their expression alternation and FA composition and content detected by GC-MS under different stress treatments, such as nitrogen depletion, salinity, high or low temperature. Our results showed that high temperature, high salinity, and nitrogen depletion treatments played significant roles in promoting microalgal FA synthesis, while FA qualities were not changed much. Correlation analysis showed that acyl carrier protein (ACP, 3-ketoacyl-ACP-synthase (KAS, and acyl-ACP thioesterase (FATA gene expression had significant correlations with monounsaturated FA (MUFA synthesis and polyunsaturated FA (PUFA synthesis. Conclusions We proposed that ACP, KAS, and FATA in H. pluvialis may play an important role in FA synthesis and may be rate limiting genes, which probably could be modified for the further study of metabolic engineering to improve microalgal biofuel quality and production.

  1. 5-Caffeoylquinic acid and caffeic acid orally administered suppresses P-selectin expression on mouse platelets

    Science.gov (United States)

    Caffeic acid and 5-caffeoylquinic acid are a naturally occurring phenolic acid and its ester found in human diets. In this paper, potential effects of caffeic acid and 5-caffeoylquinic acid found in coffee and other plant sources on platelet activation were studied via investigating P-selectin expre...

  2. Transcriptional and functional analysis of oxalyl-coenzyme A (CoA) decarboxylase and formyl-CoA transferase genes from Lactobacillus acidophilus.

    Science.gov (United States)

    Azcarate-Peril, M Andrea; Bruno-Bárcena, Jose M; Hassan, Hosni M; Klaenhammer, Todd R

    2006-03-01

    Oxalic acid is found in dietary sources (such as coffee, tea, and chocolate) or is produced by the intestinal microflora from metabolic precursors, like ascorbic acid. In the human intestine, oxalate may combine with calcium, sodium, magnesium, or potassium to form less soluble salts, which can cause pathological disorders such as hyperoxaluria, urolithiasis, and renal failure in humans. In this study, an operon containing genes homologous to a formyl coenzyme A transferase gene (frc) and an oxalyl coenzyme A decarboxylase gene (oxc) was identified in the genome of the probiotic bacterium Lactobacillus acidophilus. Physiological analysis of a mutant harboring a deleted version of the frc gene confirmed that frc expression specifically improves survival in the presence of oxalic acid at pH 3.5 compared with the survival of the wild-type strain. Moreover, the frc mutant was unable to degrade oxalate. These genes, which have not previously been described in lactobacilli, appear to be responsible for oxalate degradation in this organism. Transcriptional analysis using cDNA microarrays and reverse transcription-quantitative PCR revealed that mildly acidic conditions were a prerequisite for frc and oxc transcription. As a consequence, oxalate-dependent induction of these genes occurred only in cells first adapted to subinhibitory concentrations of oxalate and then exposed to pH 5.5. Where genome information was available, other lactic acid bacteria were screened for frc and oxc genes. With the exception of Lactobacillus gasseri and Bifidobacterium lactis, none of the other strains harbored genes for oxalate utilization.

  3. Interference of the CadC regulator in the arginine-dependent acid resistance system of Shigella and enteroinvasive E. coli.

    Science.gov (United States)

    Casalino, Mariassunta; Prosseda, Gianni; Barbagallo, Marialuisa; Iacobino, Angelo; Ceccarini, Paolo; Latella, Maria Carmela; Nicoletti, Mauro; Colonna, Bianca

    2010-06-01

    A typical pathoadaptive mutation of Shigella and enteroinvasive Escherichia coli (EIEC) is the inactivation of the cad locus which comprises the genes necessary for lysine decarboxylation, an enzyme involved in pH homoeostasis. In E. coli, the cadBA operon, encoding lysine decarboxylase (CadA) and a lysine cadaverine antiporter (CadB), is submitted to the control of CadC, a positive activator whose gene maps upstream the operon, and is transcribed independently from the same strand. CadC is an integral inner membrane protein which acts both, as signal sensor and as transcriptional regulator responding to the low pH and lysine signals. Analysis of the molecular rearrangements responsible for the loss of lysine decarboxylase activity in Shigella and EIEC has revealed that the inactivation of the cadC gene is a common feature. The 3 major adaptive acid resistance (AR) systems - AR1, AR2, and AR3 - are known to be activated at low pH by Shigella and E. coli, allowing them to withstand extremely acid conditions. In this study, evaluating the survival of S. flexneri, S. sonnei, and EIEC strains complemented with a functional cadC gene and challenged at low pH, we present evidence that CadC negatively regulates the expression of the arginine-dependent adaptive acid-resistance system (AR3), encoded by the adi locus while it has no effect on the expression of AR1 and AR2 systems. Moreover, since our results indicate that in enteroinvasive strains the presence of CadC reduces the expression of the arginine decarboxylase encoding gene adiA, it is possible to hypothesize that the loss of functionality of lysine decarboxylase is counterbalanced by a higher expression of the adi system, and that CadC, besides specifically affecting the regulation of the cadBA operon, is also relevant to other systems responding to low pH.

  4. Gene Targeting and Expression Modulation by Peptide Nucleic Acids (PNA)

    DEFF Research Database (Denmark)

    Nielsen, Peter E

    2010-01-01

    Peptide nucleic acids (PNA) are artificial structural mimics of nucleic acids capable of sequence specific hybridization to both RNA and DNA. Thus they have obvious potential as gene targeting agents for drug discovery approaches. An overview with emphasis on recent progress on RNA "interference"...

  5. The importance of SERINE DECARBOXYLASE1 (SDC1) and ethanolamine biosynthesis during embryogenesis of Arabidopsis thaliana.

    Science.gov (United States)

    Yunus, Ian Sofian; Liu, Yu-Chi; Nakamura, Yuki

    2016-11-01

    In plants, ethanolamine is considered a precursor for the synthesis of choline, which is an essential dietary nutrient for animals. An enzyme serine decarboxylase (SDC) has been identified and characterized in Arabidopsis, which directly converts serine to ethanolamine, a precursor to phosphorylethanolamine and its subsequent metabolites in plants. However, the importance of SDC and ethanolamine production in plant growth and development remains unclear. Here, we show that SDC is required for ethanolamine biosynthesis in vivo and essential in plant embryogenesis in Arabidopsis. The knockout of SDC1 caused an embryonic lethal defect due to the developmental arrest of the embryos at the heart stage. During embryo development, the expression was observed at the later stages, at which developmental defect occurred in the knockout mutant. Overexpression of SDC1 in planta increased levels of ethanolamine, phosphatidylethanolamine, and phosphatidylcholine both in leaves and siliques. These results suggest that SDC1 plays an essential role in ethanolamine biosynthesis during the embryogenesis in Arabidopsis.

  6. Phytanic acid and docosahexaenoic acid increase the metabolism of all-trans-retinoic acid and CYP26 gene expression in intestinal cells.

    Science.gov (United States)

    Lampen, A; Meyer, S; Nau, H

    2001-10-31

    Retinoids are essential for growth and cell differentiation of epithelial tissues. The effects of the food compounds phytol, the phytol metabolite phytanic acid, and the fatty acid docosahexaenoic acid (DHA) on the retinoid signaling pathway in intestinal cells were studied. Phytol inhibited the formation of all-trans-retinoic acid (RA) from dietary retinol in intestinal cells. Phytanic acid, a known retinoic X receptor (RXRalpha) and peroxisome proliferator activating receptor (PPARalpha) activator, also activated PPARdelta, and to a lesser degree PPARgamma, in a transactivation assay. Phytanic acid had no effect on intestinal RA hydroxylase CYP26 (also named P450RAI) gene expression and metabolism of all-trans-RA in intestinal Caco-2 cells. However, in combination with retinoic acid receptor (RAR)-ligands (all-trans-RA or synthetic Am580) phytanic acid enhanced the induction of CYP26 and RA-metabolism in comparison to treatments with all-trans-RA or Am580 alone. Also treatment with DHA did not affect CYP26 gene expression and RA-metabolism but cotreatment of the cells with DHA and all-trans-RA or Am580 enhanced the induction of CYP26, in comparison to the induction caused by all-trans-RA or Am580 alone. This study indicates that food compounds such as phytanic acid and DHA that are RXR-agonists and have an impact on intestinal CYP26 gene expression and metabolism of all-trans-RA in intestinal cells.

  7. Palmitic acid but not palmitoleic acid induces insulin resistance in a human endothelial cell line by decreasing SERCA pump expression.

    Science.gov (United States)

    Gustavo Vazquez-Jimenez, J; Chavez-Reyes, Jesus; Romero-Garcia, Tatiana; Zarain-Herzberg, Angel; Valdes-Flores, Jesus; Manuel Galindo-Rosales, J; Rueda, Angelica; Guerrero-Hernandez, Agustin; Olivares-Reyes, J Alberto

    2016-01-01

    Palmitic acid is a negative regulator of insulin activity. At the molecular level, palmitic acid reduces insulin stimulated Akt Ser473 phosphorylation. Interestingly, we have found that incubation with palmitic acid of human umbilical vein endothelial cells induced a biphasic effect, an initial transient elevation followed by a sustained reduction of SERCA pump protein levels. However, palmitic acid produced a sustained inhibition of SERCA pump ATPase activity. Insulin resistance state appeared before there was a significant reduction of SERCA2 expression. The mechanism by which palmitic acid impairs insulin signaling may involve endoplasmic reticulum stress, because this fatty acid induced activation of both PERK, an ER stress marker, and JNK, a kinase associated with insulin resistance. None of these effects were observed by incubating HUVEC-CS cells with palmitoleic acid. Importantly, SERCA2 overexpression decreased the palmitic acid-induced insulin resistance state. All these results suggest that SERCA pump might be the target of palmitic acid to induce the insulin resistance state in a human vascular endothelial cell line. Importantly, these data suggest that HUVEC-CS cells respond to palmitic acid-exposure with a compensatory overexpression of SERCA pump within the first hour, which eventually fades out and insulin resistance prevails.

  8. Regulation of indole-3-acetic acid biosynthesis by branched-chain amino acids in Enterobacter cloacae UW5.

    Science.gov (United States)

    Parsons, Cassandra V; Harris, Danielle M M; Patten, Cheryl L

    2015-09-01

    The soil bacterium Enterobacter cloacae UW5 produces the rhizosphere signaling molecule indole-3-acetic acid (IAA) via the indolepyruvate pathway. Expression of indolepyruvate decarboxylase, a key pathway enzyme encoded by ipdC, is upregulated by the transcription factor TyrR in response to aromatic amino acids. Some members of the TyrR regulon may also be controlled by branched-chain amino acids and here we show that expression from the ipdC promoter and production of IAA are downregulated by valine, leucine and isoleucine. Regulation of the IAA synthesis pathway by both aromatic and branched-chain amino acids suggests a broader role for this pathway in bacterial physiology, beyond plant interactions.

  9. Regulation of hepatic gene expression by saturated fatty acids.

    Science.gov (United States)

    Vallim, T; Salter, A M

    2010-01-01

    Diets rich in saturated fatty acids have long been associated with increased plasma cholesterol concentrations and hence increased risk of cardiovascular disease. More recently, they have also been suggested to promote the development of non-alcoholic fatty liver disease. While there is now considerable evidence to suggest that polyunsaturated fatty acids exert many of their effects through regulating the activity of transcription factors, including peroxisome proliferator activated receptors, sterol regulatory binding proteins (SREBPs) and liver X receptor, our understanding of how saturated fatty acids act is still limited. Here we review the potential mechanisms whereby saturated fatty acids modulate hepatic lipid metabolism thereby impacting on the synthesis, storage and secretion of lipids. Evidence is presented that their effects are, at least partly, mediated through modulation of the activity of the SREBP family of transcription factors.

  10. C-terminal residues of plant glutamate decarboxylase are required for oligomerization of a high-molecular weight complex and for activation by calcium/calmodulin.

    Science.gov (United States)

    Zik, Moriyah; Fridmann-Sirkis, Yael; Fromm, Hillel

    2006-05-01

    Bacterial glutamate decarboxylase (GAD) is a homohexameric enzyme of about 330 kDa. Plant GAD differs from the bacterial enzyme in having a C-terminal extension of 33 amino acids within which resides a calmodulin (CaM)-binding domain. In order to assess the role of the C-terminal extension in the formation of GAD complexes and in activation by Ca2+/CaM, we examined complexes formed with the purified full-length recombinant petunia GAD expressed in E. coli, and with a 9 amino acid C-terminal deletion mutant (GADDeltaC9). Size exclusion chromatography revealed that the full-length GAD formed complexes of about 580 kDa and 300 kDa in the absence of Ca2+/CaM, whereas in the presence of Ca2+/CaM all complexes shifted to approximately 680 kDa. With deletion of 9 amino acids from the C-terminus (KKKKTNRVC(500)), the ability to bind CaM in the presence of Ca2+, and to purify it by CaM-affinity chromatography was retained, but the formation of GAD complexes larger than 340 kDa and enzyme activation by Ca2+/CaM were completely abolished. Hence, responsiveness to Ca2+/CaM is associated with the formation of protein complexes of 680 kDa, and requires some or all of the nine C-terminal amino acid residues. We suggest that evolution of plant GAD from a bacterial ancestral enzyme involved the formation of higher molecular weight complexes required for activation by Ca2+/CaM.

  11. Modulation of keratinocyte gene expression and differentiation by PPAR-selective ligands and tetradecylthioacetic acid

    DEFF Research Database (Denmark)

    Westergaard, M; Henningsen, J; Svendsen, M L

    2001-01-01

    using a combination of reverse transcriptase polymerase chain reaction, Northern and Western blotting, and immunohistochemistry. PPARdelta was the predominant PPAR subtype in human keratinocytes and highly expressed in basal cells and suprabasal cells. Induction of PPARalpha and PPARgamma expression...... nuclear receptor corepressor and silence mediator for retinoid and thyroid hormone receptors. We critically evaluated the effects of selective PPAR ligands and a synthetic fatty acid analog, tetradecylthioacetic acid. Tetradecylthioacetic acid activated all human PPAR subtypes in the ranking order...... a dose-dependent induction was observed with L165041. Simultaneous addition of L165041 and BRL49653 synergistically induced strong involucrin expression. Additionally, L165041 potently induced CD36 mRNA expression. Administration of tetradecylthioacetic acid resulted in a dramatic decrease...

  12. Primary and secondary genetic responses after folic acid-induced acute renal injury in the mouse.

    Science.gov (United States)

    Calvet, J P; Chadwick, L J

    1994-12-01

    Folic acid-induced acute renal injury results in dramatic changes in gene expression. Among the genes affected by folic acid treatment are the primary response genes, c-fos and c-myc, which are thought to function to initiate cell cycle events. In this report, changes in the expression of three other genes in response to folic acid injury have been investigated: ornithine decarboxylase, epidermal growth factor (EGF), and sulfated glycoprotein-2 (SGP-2). Renal injury was found to cause a rapid decrease in EGF mRNA, which remained absent for several days after the initial injury, gradually returning to normal levels over an approximately 3-wk regeneration and recovery period. Ornithine decarboxylase mRNA showed a similar decrease. In contrast, folic acid caused a rapid increase in SGP-2 mRNA, which peaked several days after treatment, decreasing to normal levels over the 3-wk period. The mRNAs for the primary response genes were superinduced in the injured kidneys in the presence of the protein synthesis inhibitor cycloheximide. In contrast, the changes in EGF and SGP-2 mRNA levels were blocked by cycloheximide, indicating that these responses required new protein synthesis during the first few hours after folic acid injury. The opposite but parallel responses in the expression of the EGF and SGP-2 genes suggest that their regulation is coupled to the initial injury-induced dedifferentiation and subsequent return to the fully differentiated state.

  13. Expression of human acidic fibroblast growth factor in Pichia pastoris

    Institute of Scientific and Technical Information of China (English)

    YU Ying; CAI Shaoxi; Harald G. WERIRICH; XIA Yuxian

    2003-01-01

    Pichia pastoris expression system is similar to that of the mammal cell in modification of expressed protein, including refolding and glycosylation. A human aFGF gene was cloned into the intracellular expression vector pPIC9K. The Pichia pastoriS KM71 strain was transformed with the recombined expression plasmid. Transgenic expression was observed after screening the transformants with G418. The expression and secretion of recombinant human aFGF (rhaFGF) into the culture medium were testified by ELISA assay. The yield peaked after two days of induction and was approximately 10 mg.L-1 in shake-flask fermentation medium. The recombinant proteins were purified by the combination of heparin-Sepharose affinity chromatography and gel filtration chromatography. Two proteins with relative molecular masses (Mr) of 17 000 and 35 000 were purified as a single band in SDS-PAGE, whose biological activities were determined by MTT assay. It is found that the protein with Mr of 1 7 000 is nonglycosylated haFGF, and that with Mr of 35 000 is glycosylated haFGF; and the latter has a lower biological activity than the former.

  14. 37% Phosphoric Acid Induced Stronger Matrix Metalloproteinase-8 Expression of the Dental Pulp than 19% Ethylene Diamine Tetraacetic Acid

    Directory of Open Access Journals (Sweden)

    Nadie Fatimatuzzahro

    2014-11-01

    Full Text Available Etching agents such as ethylene diamine tetraacetic acid (EDTA and phosphoric acid which are widely used in adhesive restoration system aimed to increase for retention of restorative materials, may act a chemical irritant that induce inflammation of dental pulp. Inflammation is a body response against irritant and infectious agents. Matrix metalloproteinase-8, the major collagenolytic enzyme, degrades collagen type 1. This enzyme is expressed in low level in normal condition, however, the expression will increase during inflammation. The purpose of the present research was to study the effect of 19% EDTA and 37% phosphoric acid application as an etching agents on the MMP-8 expression of dental pulp. Forty-five male Sprague Dawley rats were divided into 3 groups. Cavity preparation was made on the occlusal surface of maxillary first molar using a round diamond bur. 19% EDTA, 37% phosphoric acid, and distilled water were applied on the surface of the cavity of the teeth in group I, II, and III subsequently. The cavity then filed by glass ionomer cements. The rats were sacrified at 1, 3, 5, 7, and 14 days after the treatment (n=3 for each day. The specimens were then processed histologically. Immunohistochemical (IHC analysis was performed using rabbit anti rat MMP-8 polyclonal antibody to examine MMP-8 expression and HE (Hematoxylen Eosin staining to observe the number of macrophages. The results showed 37% phosphoric acid application induced stronger expression of MMP-8 and higher number of macrophages than 19% EDTA. The strongest expression of MMP-8 seems on 5 days after the treatment where the highest number of macrophages were also found.

  15. Mutation of His465 Alters the pH-dependent Spectroscopic Properties of Escherichia coli Glutamate Decarboxylase and Broadens the Range of Its Activity toward More Alkaline pH

    NARCIS (Netherlands)

    Pennacchietti, E.; Lammens, T.M.; Capitani, G.; Franssen, M.C.R.; John, R.A.; Bossa, F.; Biase, De D.

    2009-01-01

    Glutamate decarboxylase (GadB) from Escherichia coli is a hexameric, pyridoxal 5'-phosphate-dependent enzyme catalyzing CO2 release from the a-carboxyl group of l-glutamate to yield ¿-aminobutyrate. GadB exhibits an acidic pH optimum and undergoes a spectroscopically detectable and strongly cooperat

  16. Cell biology, physiology and enzymology of phosphatidylserine decarboxylase.

    Science.gov (United States)

    Di Bartolomeo, Francesca; Wagner, Ariane; Daum, Günther

    2017-01-01

    Phosphatidylethanolamine is one of the most abundant phospholipids whose major amounts are formed by phosphatidylserine decarboxylases (PSD). Here we provide a comprehensive description of different types of PSDs in the different kingdoms of life. In eukaryotes, type I PSDs are mitochondrial enzymes, whereas other PSDs are localized to other cellular compartments. We describe the role of mitochondrial Psd1 proteins, their function, enzymology, biogenesis, assembly into mitochondria and their contribution to phospholipid homeostasis in much detail. We also discuss briefly the cellular physiology and the enzymology of Psd2. This article is part of a Special Issue entitled: Lipids of Mitochondria edited by Guenther Daum.

  17. Cloning of affecting pyruvate decarboxylase gene in the production bioethanol of agricultural waste in the E.coli bacteria

    Directory of Open Access Journals (Sweden)

    Masome Zeinali

    2016-09-01

    Full Text Available Introduction: Ethanol made by a biomass is one of the useful strategies in terms of economic and environmental and as a clean and safe energy to replace fossil fuels considered and examined. Materials and methods: In this study, key enzyme in the production of ethanol (Pyruvate decarboxylase from Zymomonas mobilis bacteria was isolated and cloned at E. coli bacteria by freeze and thaw method. For gene cloning, we used specific primers of pdc and PCR reaction and then pdc gene isolated and pET 28a plasmid double digested with (Sal I and Xho I enzymes. Digestion Products were ligated by T4 DNA ligase in 16 °C for 16 hours. Results: Results of bacteria culture showed that a few colonies containing pET 28a plasmid could grow. Result of colony pcr of pdc gene with specific primers revealed 1700 bp bands in 1% agarose gel electrophoresis. The results of PCR with T7 promotor forward primer and pdc revers primer have proved the accurate direction of integration of pdc gene into plasmid and revealed 1885 bp band. Double digestion of recombinant plasmid with SalI and XhoI enzymes revealed same bands. Finally, RT showed the expected band of 1700 bp that implies the desired gene expression in the samples. Discussion and conclusion: Due to the increased production of ethanol via pyruvate decarboxylase gene cloning in expression plasmids with a strong promoter upstream of the cloning site can conclude that, pyruvate decarboxylase cloning as a key gene would be useful and according to beneficial properties of E. coli bacteria, transfering the gene to bacteria appears to be reasonable.

  18. Quorum sensing-controlled gene expression in lactic acid bacteria

    NARCIS (Netherlands)

    Kuipers, Oscar P.; Ruyter, Pascalle G.G.A. de; Kleerebezem, Michiel; Vos, Willem M. de

    1998-01-01

    Quorum sensing in lactic acid bacteria (LAB) involves peptides that are directly sensed by membrane-located histidine kinases, after which the signal is transmitted to an intracellular response regulator. This regulator in turn activates transcription of target genes, that commonly include the struc

  19. Effect of boric acid supplementation of ostrich water on the expression of Foxn1 in thymus.

    Science.gov (United States)

    Xiao, Ke; Ansari, Abdur Rahman; Rehman, Zia Ur; Khaliq, Haseeb; Song, Hui; Tang, Juan; Wang, Jing; Wang, Wei; Sun, Peng-Peng; Zhong, Juming; Peng, Ke-Mei

    2015-11-01

    Foxn1 is essential for thymus development. The relationship between boric acid and thymus development, optimal dose of boric acid in ostrich diets, and the effects of boric acid on the expression of Foxn1 were investigated in the present study. Thirty healthy ostriches were randomly divided into six groups: Group I, II, III, IV, V, VI, and supplemented with boric acid at the concentration of 0 mg/L, 40 mg/L, 80 mg/L, 160 mg/L, 320 mg/L, 640 mg/L, respectively. The histological changes in thymus were observed by HE staining, and the expression of Foxn1 analyzed by immunohistochemistry and western blot. TUNEL method was used to label the apoptotic cells. Ostrich Foxn1 was sequenced by Race method. The results were as following: Apoptosis in ostrich thymus was closely related with boric acid concentrations. Low boric acid concentration inhibited apoptosis in thymus, but high boric acid concentration promoted apoptosis. Foxn1-positive cells were mainly distributed in thymic medulla and rarely in cortex. Foxn1 is closely related to thymus growth and development. The nucleotide sequence and the encoded protein of Foxn1 were 2736 bases and 654 amino acids in length. It is highly conserved as compared with other species. These results demonstrated that the appropriate boric acid supplementation in water would produce positive effects on the growth development of ostrich thymus by promoting Foxn1 expression, especially at 80 mg/L, and the microstructure of the thymus of ostrich fed 80 mg/L boric acid was well developed. The supplementation of high dose boron (>320 mg/L) damaged the microstructure of thymus and inhibited the immune function by inhibiting Foxn1 expression, particularly at 640 mg/L. The optimal dose of boric acid supplementation in ostrich diets is 80 mg/L boric acid. The genomic full-length of African ostrich Foxn1 was cloned for the first time in the study.

  20. Generating knock-in parasites: integration of an ornithine decarboxylase transgene into its chromosomal locus in Leishmania donovani.

    Science.gov (United States)

    Roberts, Sigrid C; Kline, Chelsey; Liu, Wei; Ullman, Buddy

    2011-06-01

    Leishmania null mutants created by targeted gene replacement are typically complemented with chimeric episomes harboring the replaced gene in order to validate that the observed phenotype is due to the specific gene deletion. However, the current inventory of available episomes for complementation of genetic lesions in Leishmania is unstable in the absence of drug selection, and levels of gene expression cannot be controlled, especially in vivo. To circumvent this impediment, a strategy to re-introduce the targeted gene into the original chromosomal locus to generate "knock-in" parasites within selectable null backgrounds has been developed. A genomic fragment encompassing the ornithine decarboxylase locus and lacking heterologous DNA sequences was transfected into ornithine decarboxylase-deficient Leishmania donovani. The construct randomly integrated into either chromosomal allele by homologous recombination restoring polyamine prototrophy and revealing that LdODC was functionally expressed in the knock-in clones. This strategy offers a mechanism for complementing a genetic lesion amenable to positive selection in a manner that facilitates stable gene expression from its original locus in the absence of continuous drug pressure.

  1. Effects of Long Chain Fatty Acid Synthesis and Associated Gene Expression in Microalga Tetraselmis sp.

    Directory of Open Access Journals (Sweden)

    T. Catalina Adarme-Vega

    2014-06-01

    Full Text Available With the depletion of global fish stocks, caused by high demand and effective fishing techniques, alternative sources for long chain omega-3 fatty acids are required for human nutrition and aquaculture feeds. Recent research has focused on land-based cultivation of microalgae, the primary producers of omega-3 fatty acids in the marine food web. The effect of salinity on fatty acids and related gene expression was studied in the model marine microalga, Tetraselmis sp. M8. Correlations were found for specific fatty acid biosynthesis and gene expression according to salinity and the growth phase. Low salinity was found to increase the conversion of C18:4 stearidonic acid (SDA to C20:4 eicosatetraenoic acid (ETA, correlating with increased transcript abundance of the Δ-6-elongase-encoding gene in salinities of 5 and 10 ppt compared to higher salinity levels. The expression of the gene encoding β-ketoacyl-coenzyme was also found to increase at lower salinities during the nutrient deprivation phase (Day 4, but decreased with further nutrient stress. Nutrient deprivation also triggered fatty acids synthesis at all salinities, and C20:5 eicosapentaenoic acid (EPA increased relative to total fatty acids, with nutrient starvation achieving a maximum of 7% EPA at Day 6 at a salinity of 40 ppt.

  2. Expression of fatty acid and lipid biosynthetic genes in developing endosperm of Jatropha curcas

    Directory of Open Access Journals (Sweden)

    Gu Keyu

    2012-07-01

    Full Text Available Abstract Background Temporal and spatial expression of fatty acid and lipid biosynthetic genes are associated with the accumulation of storage lipids in the seeds of oil plants. In jatropha (Jatropha curcas L., a potential biofuel plant, the storage lipids are mainly synthesized and accumulated in the endosperm of seeds. Although the fatty acid and lipid biosynthetic genes in jatropha have been identified, the expression of these genes at different developing stages of endosperm has not been systemically investigated. Results Transmission electron microscopy study revealed that the oil body formation in developing endosperm of jatropha seeds initially appeared at 28 days after fertilization (DAF, was actively developed at 42 DAF and reached to the maximum number and size at 56 DAF. Sixty-eight genes that encode enzymes, proteins or their subunits involved in fatty acid and lipid biosynthesis were identified from a normalized cDNA library of jatropha developing endosperm. Gene expression with quantitative reverse-transcription polymerase chain reaction analysis demonstrated that the 68 genes could be collectively grouped into five categories based on the patterns of relative expression of the genes during endosperm development. Category I has 47 genes and they displayed a bell-shaped expression pattern with the peak expression at 28 or 42 DAF, but low expression at 14 and 56 DAF. Category II contains 8 genes and expression of the 8 genes was constantly increased from 14 to 56 DAF. Category III comprises of 2 genes and both genes were constitutively expressed throughout endosperm development. Category IV has 9 genes and they showed a high expression at 14 and 28 DAF, but a decreased expression from 42 to 56 DAF. Category V consists of 2 genes and both genes showed a medium expression at 14 DAF, the lowest expression at 28 or 42 DAF, and the highest expression at 56 DAF. In addition, genes encoding enzymes or proteins with similar function were

  3. Treatment of idiopathic parkinsonism with L-dopa in the absence and presence of decarboxylase inhibitors: effects on plasma levels of L-dopa, dopa decarboxylase, catecholamines and 3-O-methyl-dopa.

    Science.gov (United States)

    Boomsma, F; Meerwaldt, J D; Man in't Veld, A J; Hovestadt, A; Schalekamp, M A

    1989-05-01

    The effect of levodopa (L-dopa), alone or in combination with a peripheral decarboxylase inhibitor (PDI), on plasma levels of aromatic-L-amino acid decarboxylase (ALAAD, = dopa decarboxylase), L-dopa, 3-O-methyl-dopa (3-OMD), dopamine (DA), noradrenaline, adrenaline and dopamine beta-hydroxylase has been studied. In healthy subjects and in patients with parkinsonism plasma ALAAD level fell after administration of L-dopa + benserazide, but returned to previous levels within 90 min. In a cross-sectional study blood was obtained, 2 h after dosing, from 104 patients with idiopathic parkinsonism, divided into four groups: no L-dopa treatment (group 1), L-dopa alone (group 2), L-dopa + benserazide (Madopar) (group 3) and L-dopa + carbidopa (Sinemet) (group 4). Plasma ALAAD, which was normal in groups 1 and 2, was increased 3-fold in groups 3 and 4, indicating that there was induction of ALAAD by the co-administration of PDI. Despite this induction of ALAAD, in groups 3 and 4, with half the daily L-dopa dose compared with group 2, plasma L-dopa and 3-OMD levels were 5 times higher, while plasma DA levels were not different. The DA/L-dopa ratio was decreased 5-fold in group 2 and 16-fold in groups 3 and 4 as compared with group 1. Neither 3-OMD levels nor 3-OMD/L-dopa ratios correlated with the occurrence of on-off fluctuations. In a longitudinal study of three patients started on Madopar treatment the induction of plasma ALAAD was found to occur gradually over 3-4 weeks. Further detailed pharmacokinetic studies in plasma and cerebrospinal fluid are required in order to elucidate whether the ALAAD induction by PDI may be related to the loss of clinical efficacy of combination therapy in some patients and how it is related to end-of-dose deterioration and on-off phenomena.

  4. Acid environments affect biofilm formation and gene expression in isolates of Salmonella enterica Typhimurium DT104.

    Science.gov (United States)

    O'Leary, Denis; McCabe, Evonne M; McCusker, Matthew P; Martins, Marta; Fanning, Séamus; Duffy, Geraldine

    2015-08-01

    The aim of this study was to examine the survival and potential virulence of biofilm-forming Salmonella Typhimurium DT104 under mild acid conditions. Salmonella Typhimurium DT104 employs an acid tolerance response (ATR) allowing it to adapt to acidic environments. The threat that these acid adapted cells pose to food safety could be enhanced if they also produce biofilms in acidic conditions. The cells were acid-adapted by culturing them in 1% glucose and their ability to form biofilms on stainless steel and on the surface of Luria Bertani (LB) broth at pH7 and pH5 was examined. Plate counts were performed to examine cell survival. RNA was isolated from cells to examine changes in the expression of genes associated with virulence, invasion, biofilm formation and global gene regulation in response to acid stress. Of the 4 isolates that were examined only one (1481) that produced a rigid biofilm in LB broth at pH7 also formed this same structure at pH5. This indicated that the lactic acid severely impeded the biofilm producing capabilities of the other isolates examined under these conditions. Isolate 1481 also had higher expression of genes associated with virulence (hilA) and invasion (invA) with a 24.34-fold and 13.68-fold increase in relative gene expression respectively at pH5 compared to pH7. Although genes associated with biofilm formation had increased expression in response to acid stress for all the isolates this only resulted in the formation of a biofilm by isolate 1481. This suggests that in addition to the range of genes associated with biofilm production at neutral pH, there are genes whose protein products specifically aid in biofilm production in acidic environments. Furthermore, it highlights the potential for the use of lactic acid for the inhibition of Salmonella biofilms.

  5. Functionally diverse biotin-dependent enzymes with oxaloacetate decarboxylase activity.

    Science.gov (United States)

    Lietzan, Adam D; St Maurice, Martin

    2014-02-15

    Biotin-dependent enzymes catalyze carboxylation, decarboxylation and transcarboxylation reactions that participate in the primary metabolism of a wide range of organisms. In all cases, the overall reaction proceeds via two half reactions that take place in physically distinct active sites. In the first half-reaction, a carboxyl group is transferred to the 1-N' of a covalently tethered biotin cofactor. The tethered carboxybiotin intermediate subsequently translocates to a second active site where the carboxyl group is either transferred to an acceptor substrate or, in some bacteria and archaea, is decarboxylated to biotin and CO2 in order to power the export of sodium ions from the cytoplasm. A homologous carboxyltransferase domain is found in three enzymes that catalyze diverse overall reactions: carbon fixation by pyruvate carboxylase, decarboxylation and sodium transport by the biotin-dependent oxaloacetate decarboxylase complex, and transcarboxylation by transcarboxylase from Propionibacterium shermanii. Over the past several years, structural data have emerged which have greatly advanced the mechanistic description of these enzymes. This review assembles a uniform description of the carboxyltransferase domain structure and catalytic mechanism from recent studies of pyruvate carboxylase, oxaloacetate decarboxylase and transcarboxylase, three enzymes that utilize an analogous carboxyltransferase domain to catalyze the biotin-dependent decarboxylation of oxaloacetate.

  6. Engineering salidroside biosynthetic pathway in hairy root cultures of Rhodiola crenulata based on metabolic characterization of tyrosine decarboxylase.

    Directory of Open Access Journals (Sweden)

    Xiaozhong Lan

    Full Text Available Tyrosine decarboxylase initializes salidroside biosynthesis. Metabolic characterization of tyrosine decarboxylase gene from Rhodiola crenulata (RcTYDC revealed that it played an important role in salidroside biosynthesis. Recombinant 53 kDa RcTYDC converted tyrosine into tyramine. RcTYDC gene expression was induced coordinately with the expression of RcUDPGT (the last gene involved in salidroside biosynthesis in SA/MeJA treatment; the expression of RcTYDC and RcUDPGT was dramatically upregulated by SA, respectively 49 folds and 36 folds compared with control. MeJA also significantly increased the expression of RcTYDC and RcUDPGT in hairy root cultures. The tissue profile of RcTYDC and RcUDPGT was highly similar: highest expression levels found in stems, higher expression levels in leaves than in flowers and roots. The gene expressing levels were consistent with the salidroside accumulation levels. This strongly suggested that RcTYDC played an important role in salidroside biosynthesis in R. crenulata. Finally, RcTYDC was used to engineering salidroside biosynthetic pathway in R. crenulata hairy roots via metabolic engineering strategy of overexpression. All the transgenic lines showed much higher expression levels of RcTYDC than non-transgenic one. The transgenic lines produced tyramine, tyrosol and salidroside at higher levels, which were respectively 3.21-6.84, 1.50-2.19 and 1.27-3.47 folds compared with the corresponding compound in non-transgenic lines. In conclusion, RcTYDC overexpression promoted tyramine biosynthesis that facilitated more metabolic flux flowing toward the downstream pathway and as a result, the intermediate tyrosol was accumulated more that led to the increased production of the end-product salidroside.

  7. Increased expression of sialic acid in cervical biopsies with squamous intraepithelial lesions

    Directory of Open Access Journals (Sweden)

    Vallejo-Ruiz Verónica

    2010-11-01

    Full Text Available Abstract Background Altered sialylation has been observed during oncogenic transformation. Sialylated oligosaccharides of glycoproteins and glycolipids have been implicated in tumor progression and metastases. In the cervical cancer high levels of sialic acid have been reported in the patients serum, and an increased of total sialic acid concentration has been reported for the cervical neoplasia and cervical cancer. This study investigates the changes in expression and distribution of α2,3-linked sialic acid and α2,6- linked sialic acid in low and high squamous intraepithelial lesions and in normal tissue. Methods Lectin histochemistry was used to examine the expression and distribution of sialic acid in different grades of cervical neoplasia. We applied Maackia amurensis lectin, which interacts with α2,3-linked sialic acid and Sambucus nigra lectin specific for α2,6-linked sialic acid. Results The histochemical analysis showed that α2,3-linked sialic acid and α2,6- linked sialic acid increased in intensity and distribution in concordance with the grade of squamous intraepithelial lesion (SIL. These results are in concordance with a previous study that reports increased RNAm levels of three sialyltransferases. Conclusions These results show that the change in sialylation occurs before cancer development and may play an important role in cellular transformation. These findings provide the basis for more detailed studies of the possible role of cell surface glycoconjugates bearing sialic acid in the cellular cervix transformation.

  8. Production of itaconic acid in Escherichia coli expressing recombinant α-amylase using starch as substrate.

    Science.gov (United States)

    Okamoto, Shusuke; Chin, Taejun; Nagata, Keisuke; Takahashi, Tetsuya; Ohara, Hitomi; Aso, Yuji

    2015-05-01

    Several studies on fermentative production of a vinyl monomer itaconic acid from hydrolyzed starch using Aspergillus terreus have been reported. Herein, we report itaconic acid production by Escherichia coli expressing recombinant α-amylase, using soluble starch as its sole carbon source. To express α-amylase in E. coli, we first constructed recombinant plasmids expressing α-amylases by using cell surface display technology derived from two amylolytic bacteria, Bacillus amyloliquefaciens NBRC 15535(T) and Streptococcus bovis NRIC 1535. The recombinant α-amylase from S. bovis (SBA) showed activity at 28°C, which is the optimal temperature for production of itaconic acid, while α-amylase from B. amyloliquefaciens displayed no noticeable activity. E. coli cells expressing SBA produced 0.15 g/L itaconic acid after 69 h cultivation under pH-stat conditions, using 1% starch as the sole carbon source. In fact, E. coli cells expressing SBA had similar growth rates when grown in the presence of 1% glucose or starch, thereby highlighting the expression of an active α-amylase that enabled utilization of starch to produce itaconic acid in E. coli.

  9. Combining eicosapentaenoic acid, decosahexaenoic acid and arachidonic acid, using a fully crossed design, affect gene expression and eicosanoid secretion in salmon head kidney cells in vitro.

    Science.gov (United States)

    Holen, Elisabeth; He, Juyun; Espe, Marit; Chen, Liqiou; Araujo, Pedro

    2015-08-01

    Future feed for farmed fish are based on untraditional feed ingredients, which will change nutrient profiles compared to traditional feed based on marine ingredients. To understand the impact of oils from different sources on fish health, n-6 and n-3 polyunsaturated fatty acids (PUFAs) were added to salmon head kidney cells, in a fully crossed design, to monitor their individual and combined effects on gene expression. Exposing salmon head kidney cells to single fatty acids, arachidonic acid (AA) or decosahexaenoic acid (DHA), resulted in down-regulation of cell signaling pathway genes and specific fatty acid metabolism genes as well as reduced prostaglandin E2 (PGE2) secretion. Eicosapentaenoic acid (EPA) had no impact on gene transcription in this study, but reduced the cell secretion of PGE2. The combined effect of AA + EPA resulted in up-regulation of eicosanoid pathway genes and the pro-inflammatory cytokine, tumor necrosis factor alpha (TNF-α), Bclx (an inducer of apoptosis) and fatty acid translocase (CD36) as well as increased cell secretion of PGE2 into the media. Adding single fatty acids to salmon head kidney cells decreased inflammation markers in this model. The combination AA + EPA acted differently than the rest of the fatty acid combinations by increasing the inflammation markers in these cells. The concentration of fatty acid used in this experiment did not induce any lipid peroxidation responses.

  10. Biogenic Amine Degradation by Bacillus Species Isolated from Traditional Fermented Soybean Food and Detection of Decarboxylase-Related Genes.

    Science.gov (United States)

    Eom, Jeong Seon; Seo, Bo Young; Choi, Hye Sun

    2015-09-01

    Biogenic amines in some food products present considerable toxicological risks as potential human carcinogens when consumed in excess concentrations. In this study, we investigated the degradation of the biogenic amines histamine and tyramine and the presence of genes encoding histidine and tyrosine decarboxylases and amine oxidase in Bacillus species isolated from fermented soybean food. No expression of histidine and tyrosine decarboxylase genes (hdc and tydc) were detected in the Bacillus species isolated (B. subtilis HJ0-6, B. subtilis D'J53-4, and B. idriensis RD13-10), although substantial levels of amine oxidase gene (yobN) expression were observed. We also found that the three selected strains, as non-biogenic amineproducing bacteria, were significantly able to degrade the biogenic amines histamine and tyramine. These results indicated that the selected Bacillus species could be used as a starter culture for the control of biogenic amine accumulation and degradation in food. Our study findings also provided the basis for the development of potential biological control agents against these biogenic amines for use in the food preservation and food safety sectors.

  11. Docosahexaenoic acid regulates gene expression in HUVEC cells treated with polycyclic aromatic hydrocarbons.

    Science.gov (United States)

    Gdula-Argasińska, Joanna; Czepiel, Jacek; Totoń-Żurańska, Justyna; Jurczyszyn, Artur; Perucki, William; Wołkow, Paweł

    2015-07-16

    The molecular mechanism of inflammation and carcinogenesis induced by exposure of polycyclic aromatic hydrocarbons (PAHs) is not clearly understood. Our study was undertaken due to the strong pro-carcinogenic potential and reactivity of PAH-metabolites, as well as the susceptibility of polyunsaturated fatty acids to oxidation. The aim of this study was to evaluate the pro- or anti-inflammatory impact of n-3 docosahexaenoic acid on human primary umbilical vein endothelial cells (HUVEC) exposed to polycyclic aromatic hydrocarbons. We analysed the influence of docosahexaenoic acid (DHA) and/or PAHs supplementation on the fatty acid profile of cell membranes, on cyclooxygenase-2 (COX-2), aryl hydrocarbon receptor (AHR), and glutathione S transferase Mu1 (GSTM1) protein expression as well as on the prostaglandin synthase 2 (PTGS2), AHR, GSTM1, PLA2G4A, and cytochrome P450 CYP1A1 gene expression. We observed that COX-2 and AHR protein expression was increased while GSTM1 expression was decreased in cells exposed to DHA and PAHs. Docosahexaenoic acid down-regulated CYP1A1 and up-regulated the AHR and PTGS2 genes. Our findings suggested that DHA contributes significantly to alleviate the harmful effects caused by PAHs in endothelial cells. Moreover, these results suggest that a diet rich in n-3 fatty acids is helpful to reduce the harmful effects of PAHs exposure on human living in heavily polluted areas.

  12. Characterization of an avian histidine decarboxylase and localization of histaminergic neurons in the chicken brain.

    Science.gov (United States)

    Bessho, Yuki; Iwakoshi-Ukena, Eiko; Tachibana, Tetsuya; Maejima, Sho; Taniuchi, Shusuke; Masuda, Keiko; Shikano, Kenshiro; Kondo, Kunihiro; Furumitsu, Megumi; Ukena, Kazuyoshi

    2014-08-22

    In mammals, it is established that histamine is a neurotransmitter and/or neuromodulator in the central nervous system. It is produced by the enzyme histidine decarboxylase (HDC) in the tuberomammillary nucleus of the posterior hypothalamus. However, HDC as well as histaminergic neurons have not yet been characterized in the avian brain. We have cloned the cDNA for HDC from the chicken hypothalamus and demonstrated that the chicken HDC sequence is highly homologous to the mammalian counterpart, and that the expressed protein shows high enzymatic activity. The expression of HDC mRNA at various sites in the brain was investigated using quantitative RT-PCR. The results showed that the HDC mRNA was highly expressed in the hypothalamic infundibulum. In situ hybridization analyses revealed that the cells containing HDC mRNA were localized in the medial mammillary nucleus of the hypothalamic infundibulum. Intracerebroventricular injection of histamine in chicks resulted in inhibition of feeding behavior. This is the first report of the characterization of histaminergic neurons in the avian brain, and our findings indicate that neuronal histamine exerts anorexigenic effects in chicks.

  13. Antitumor Effect of Antisense Ornithine Decarboxylase Adenovirus on Human Lung Cancer Cells

    Institute of Scientific and Technical Information of China (English)

    Hui TIAN; Lin LI; Xian-Xi LIU; Yan ZHANG

    2006-01-01

    Ornithine decarboxylase (ODC), the first enzyme of polyamine biosynthesis, was found to increase in cancer cells, especially lung cancer cells. Some chemotherapeutic agents aimed at decreasing ODC gene expression showed inhibitory effects on cancer cells. In this study, we examined the effects of adenoviral transduced antisense ODC on lung cancer cells. An adenovirus carrying antisense ODC (rAd-ODC/Ex3as) was used to infect lung cancer cell line A-549. The 3-(4,5-me thylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was used to analyze the effect on cell growth. Expression of ODC and concentration of polyamines in cells were determined by Western blot analysis and high performance liquid chromatography. Terminal deoxynucleotidyl transferase-mediated biotin-dUTP nick-end labeling was used to analyze cell apoptosis. The expression of ODC in A-549 cells was reduced to 54%, and that of three polyamines was also decreased through the rAd-ODC/Ex3as treatment. Consequently, cell growth was substantially inhibited and terminal deoxynucleotidyl transferase-mediated biotin-dUTP nick-end labeling showed that rAd-ODC/Ex3as could lead to cell apoptosis, with apoptosis index of 46%. This study suggests that rAd-ODC/Ex3as has an antitumor effect on the human lung cancer cells.

  14. Expression of dehydratase domains from a polyunsaturated fatty acid synthase increases the production of fatty acids in Escherichia coli.

    Science.gov (United States)

    Oyola-Robles, Delise; Rullán-Lind, Carlos; Carballeira, Néstor M; Baerga-Ortiz, Abel

    2014-02-05

    Increasing the production of fatty acids by microbial fermentation remains an important step toward the generation of biodiesel and other portable liquid fuels. In this work, we report an Escherichia coli strain engineered to overexpress a fragment consisting of four dehydratase domains from the polyunsaturated fatty acid (PUFA) synthase enzyme complex from the deep-sea bacterium, Photobacterium profundum. The DH1-DH2-UMA enzyme fragment was excised from its natural context within a multi-enzyme PKS and expressed as a stand-alone protein. Fatty acids were extracted from the cell pellet, esterified with methanol and quantified by GC-MS analysis. Results show that the E. coli strain expressing the DH tetradomain fragment was capable of producing up to a 5-fold increase (80.31 mg total FA/L culture) in total fatty acids over the negative control strain lacking the recombinant enzyme. The enhancement in production was observed across the board for all the fatty acids that are typically made by E. coli. The overexpression of the DH tetradomain did not affect E. coli cell growth, thus showing that the observed enhancement in fatty acid production was not a result of effects associated with cell density. The observed enhancement was more pronounced at lower temperatures (3.8-fold at 16 °C, 3.5-fold at 22 °C and 1.5-fold at 30 °C) and supplementation of the media with 0.4% glycerol did not result in an increase in fatty acid production. All these results taken together suggest that either the dehydration of fatty acid intermediates are a limiting step in the E. coli fatty acid biosynthesis machinery, or that the recombinant dehydratase domains used in this study are also capable of catalyzing thioester hydrolysis of the final products. The enzyme in this report is a new tool which could be incorporated into other existing strategies aimed at improving fatty acid production in bacterial fermentations toward accessible biodiesel precursors.

  15. Identification and transcript analysis of two glutamate decarboxylase genes, CsGAD1 and CsGAD2, reveal the strong relationship between CsGAD1 and citrate utilization in citrus fruit.

    Science.gov (United States)

    Liu, Xiao; Hu, Xiao-Mei; Jin, Long-Fei; Shi, Cai-Yun; Liu, Yong-Zhong; Peng, Shu-Ang

    2014-09-01

    Glutamate decarboxylase (GAD, EC 4.1.1.15) has been suggested to be a key, regulatory point in the biosynthesis of γ-aminobutyrate (GABA) and in the utilization of citric acid through GABA shunt pathway. In this study we discovered two GAD genes, named as CsGAD1 and CsGAD2, in citrus genome database and then successfully cloned. Both CsGAD1 and CsGAD2 have a putative pyridoxal 5-phosphate binding domain in the middle region and a putative calmodulin-binding domain at the carboxyl terminus. Gene structure analysis showed that much difference exists in the size of exons and introns or in cis-regulatory elements in promoter region between the two GAD genes. Gene expression indicated that CsGAD1 transcript was predominantly expressed in flower and CsGAD2 transcript was predominantly expressed in fruit juice sacs; in the ripening fruit, CsGAD1 transcript level was at least 2-time higher than CsGAD2 transcript level. Moreover, CsGAD1 transcript level was increased significantly along with the increase of GAD activity and accompanied by a significant decrease of titratable acid (TA), suggesting that it is CsGAD1 rather than CsGAD2 plays a role in the citric acid utilization during fruit ripening. In addition, injection of abscisic acid and foliar spray of K2SO4 significantly increased the TA content of Satsuma mandarin, and significantly decreased GAD activity as well as CsGAD1 transcript, further suggesting the important role of CsGAD1 in the citrate utilization of citrus fruit.

  16. 3-hydroxi-anthranilic acid is early expressed in stroke

    Directory of Open Access Journals (Sweden)

    A. Mangas

    2016-12-01

    Full Text Available Using an immunohistochemical technique, we have studied the distribution of 3-OH-anthranilic acid (3-HAA in the rat brain. Our study was carried out in control animals and in rats in which a stroke model (single transient middle cerebral artery occlusion was performed. A monoclonal antibody directed against 3-HAA was also developed. 3-HAA was exclusively observed in the infarcted regions (ipsilateral striatum/cerebral cortex, 2, 5 and 21 days after the induction of stroke. In control rats and in the contralateral side of the stroke animals, no immunoreactivity for 3-HAA was visualized. Under pathological conditions (from early phases of stroke, we reported for the first time the presence of 3-HAA in the mammalian brain. By double immunohistochemistry, the coexistence of 3-HAA and GFAP was observed in astrocytes. The distribution of 3-HAA matched perfectly with the infarcted regions. Our findings suggest that, in stroke, 3-HAA could be involved in the tissue damage observed in the infarcted regions, since it is well known that 3-HAA exerts cytotoxic effects.

  17. Expression and localization of the omega-3 fatty acid receptor GPR120 in human term placenta.

    Science.gov (United States)

    Lager, S; Ramirez, V I; Gaccioli, F; Jansson, T; Powell, T L

    2014-07-01

    Fatty acids can function as signaling molecules, acting through receptors in the cytosol or on the cell surface. G-Protein Receptor (GPR)120 is a membrane-bound receptor mediating anti-inflammatory and insulin-sensitizing effects of the omega-3 fatty acid docohexaenoic acid (DHA). GPR120 dysfunction is associated with obesity in humans. Cellular localization of GPR120 and the influence of maternal obesity on GPR120 protein expression in the placenta are unknown. Herein we demonstrate that GPR120 is predominantly expressed in the microvillous membrane (MVM) of human placenta and that the expression level of this receptor in MVM is not altered by maternal body mass index (BMI).

  18. Expression of the SNAT2 amino acid transporter during the development of rat cerebral cortex.

    Science.gov (United States)

    Rodríguez, Angelina; Angelina, Rodríguez; Berumen, Laura C; Francisco, Zafra; Giménez, Cecilio; Cecilio, Giménez; García-Alcocer, María Guadalupe; Guadalupe, García-Alcocer María

    2011-11-01

    The sodium-coupled neutral amino acid transporter 2 (SNAT2) is a protein that is expressed ubiquitously in mammalian tissues and that displays Na(+), voltage and pH dependent activity. This transporter mediates the passage of small zwitterionic amino acids across the cell membrane and regulates the cell homeostasis and its volume. We have examined the expression of SNAT2 mRNA and protein during the development of the rat cerebral cortex, from gestation through the postnatal stages to adulthood. Our data reveal that SNAT2 mRNA and protein expression is higher during embryogenesis, while it subsequently diminishes during postnatal development. Moreover, during embryonic period SNAT2 colocalizes with the radial glial cells marker GLAST, while in postnatal period it is mainly detected in neuronal dendrites. These findings suggest a relevant role for amino acid transport through SNAT2 in the developing embryonic brain.

  19. Expression of a coriander desaturase results in petroselinic acid production in transgenic tobacco

    Energy Technology Data Exchange (ETDEWEB)

    Cahoon, E.B.; Shanklin, J.; Ohlrogge, J.B. (Michigan State Univ., East Lansing (United States))

    1992-12-01

    Little is known about the metabolic origin of petroselinic acid (18:1[Delta][sup 6cis]), the principal fatty acid of the seed oil of most Umbelliferae, Araliaceae, and Garryaceae species. To examine the possibility that petroselinic acid is the product of an acyl-acyl carrier protein (ACP) desaturase, Western blots of coriander and other Umbelliferae seed extracts were probed with antibodies against the [Delta][sup 9]-stearoyl-ACP desaturase of avocado. In these extracts, proteins of 39 and 36 kDa were detected. Of these, only the 36-kDa peptide was specific to tissues which synthesize petroselinic acid. A cDNA encoding the 36-kDa peptide was isolated from a coriander endosperm cDNA library, placed under control of the cauliflower mosaic virus 35S promoter, and introduced into tobacco by Agrobacterium tumefaciens-mediated transformation. Expression of this cDNA in transgenic tobacco callus was accompanied by the accumulation of petroselinic acid and [Delta][sup 4]-hexadecenoic acid, both of which were absent from control callus. These results demonstrate the involvement of a 36-kDa putative acyl-ACP desaturase in the biosynthetic pathway of petroselinic acid and the ability to produce fatty acids of unusual structure in transgenic plants by the expression of the gene for this desaturase. 27 refs., 5 figs.

  20. Expression of a coriander desaturase results in petroselinic acid production in transgenic tobacco.

    Science.gov (United States)

    Cahoon, E B; Shanklin, J; Ohlrogge, J B

    1992-12-01

    Little is known about the metabolic origin of petroselinic acid (18:1 delta 6cis), the principal fatty acid of the seed oil of most Umbelliferae, Araliaceae, and Garryaceae species. To examine the possibility that petroselinic acid is the product of an acyl-acyl carrier protein (ACP) desaturase, Western blots of coriander and other Umbelliferae seed extracts were probed with antibodies against the delta 9-stearoyl-ACP desaturase of avocado. In these extracts, proteins of 39 and 36 kDa were detected. Of these, only the 36-kDa peptide was specific to tissues which synthesize petroselinic acid. A cDNA encoding the 36-kDa peptide was isolated from a coriander endosperm cDNA library, placed under control of the cauliflower mosaic virus 35S promoter, and introduced into tobacco by Agrobacterium tumefaciens-mediated transformation. Expression of this cDNA in transgenic tobacco callus was accompanied by the accumulation of petroselinic acid and delta 4-hexadecenoic acid, both of which were absent from control callus. These results demonstrate the involvement of a 36-kDa putative acyl-ACP desaturase in the biosynthetic pathway of petroselinic acid and the ability to produce fatty acids of unusual structure in transgenic plants by the expression of the gene for this desaturase.

  1. Involvement of Sp1 in Butyric Acid-Induced HIV-1 Gene Expression

    Directory of Open Access Journals (Sweden)

    Kenichi Imai

    2015-09-01

    Full Text Available Background/Aims: The ability of human immunodeficiency virus-1(HIV-1 to establish latent infection and its re-activation is considered critical for progression of HIV-1 infection. We previously reported that a bacterial metabolite butyric acid, acting as a potent inhibitor of histone deacetylases (HDACs, could lead to induction of HIV-1 transcription; however, the molecular mechanism remains unclear. The aim of this study was to investigate the effect of butyric acid on HIV-1 gene expression. Methods: Butyric acid-mediated HIV-1 gene expression was determined by luciferase assay and Chromatin immunoprecipitation assay. Western blot analysis and ELISA were used for the detection of HIV-1. Results: We found that Sp1 binding sites within the HIV-1 promoter are primarily involved in butyric acid-mediated HIV-1 activation. In fact, Sp1 knockdown by small interfering RNA and the Sp1 inhibitor mithramycin A abolished the effect of butyric acid. We also observed that cAMP response element-binding-binding protein (CBP was required for butyric acid-induced HIV-1 activation. Conclusions: These results suggest that butyric acid stimulates HIV-1 promoter through inhibition of the Sp1-associated HDAC activity and recruitment of CBP to the HIV-1 LTR. Our findings suggest that Sp1 should be considered as one of therapeutic targets in anti-viral therapy against HIV-1 infection aggravated by butyric acid-producing bacteria.

  2. The timing of administration, dose dependence and efficacy of dopa decarboxylase inhibitors on the reversal of motor disability produced by L-DOPA in the MPTP-treated common marmoset.

    Science.gov (United States)

    Tayarani-Binazir, Kayhan A; Jackson, Michael J; Fisher, Ria; Zoubiane, Ghada; Rose, Sarah; Jenner, Peter

    2010-06-10

    Dopa decarboxylase inhibitors are routinely used to potentiate the effects of L-DOPA in the treatment of Parkinson's disease. However, neither in clinical use nor in experimental models of Parkinson's disease have the timing and dose of dopa decarboxylase inhibitors been thoroughly explored. We now report on the choice of dopa decarboxylase inhibitors, dose and the time of dosing relationships of carbidopa, benserazide and L-alpha-methyl dopa (L-AMD) in potentiating the effects of L-DOPA in the 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine (MPTP)-treated common marmoset. Pre-treatment with benserazide for up to 3h did not alter the motor response to L-DOPA compared to simultaneous administration with L-DOPA. There was some evidence of a relationship between carbidopa and benserazide dose and increased locomotor activity and the reversal of motor disability. But in general, commonly used dose levels of dopa decarboxylase inhibitors appeared to produce a maximal motor response to L-DOPA. In contrast, dyskinesia intensity and duration continued to increase with both carbidopa and benserazide dose. The novel dopa decarboxylase inhibitor, L-AMD, increased locomotor activity and improved motor disability to the same extent as carbidopa or benserazide but importantly this was accompanied by significantly less dyskinesia. This study shows that currently, dopa decarboxylase inhibitors may be routinely employed in the MPTP-treated primate at doses which are higher than those necessary to produce a maximal potentiation of the anti-parkinsonian effect of L-DOPA. This may lead to excessive expression of dyskinesia in this model of Parkinson's disease and attention should be given to the dose regimens currently employed.

  3. Interpreting expression data with metabolic flux models: predicting Mycobacterium tuberculosis mycolic acid production.

    Directory of Open Access Journals (Sweden)

    Caroline Colijn

    2009-08-01

    Full Text Available Metabolism is central to cell physiology, and metabolic disturbances play a role in numerous disease states. Despite its importance, the ability to study metabolism at a global scale using genomic technologies is limited. In principle, complete genome sequences describe the range of metabolic reactions that are possible for an organism, but cannot quantitatively describe the behaviour of these reactions. We present a novel method for modeling metabolic states using whole cell measurements of gene expression. Our method, which we call E-Flux (as a combination of flux and expression, extends the technique of Flux Balance Analysis by modeling maximum flux constraints as a function of measured gene expression. In contrast to previous methods for metabolically interpreting gene expression data, E-Flux utilizes a model of the underlying metabolic network to directly predict changes in metabolic flux capacity. We applied E-Flux to Mycobacterium tuberculosis, the bacterium that causes tuberculosis (TB. Key components of mycobacterial cell walls are mycolic acids which are targets for several first-line TB drugs. We used E-Flux to predict the impact of 75 different drugs, drug combinations, and nutrient conditions on mycolic acid biosynthesis capacity in M. tuberculosis, using a public compendium of over 400 expression arrays. We tested our method using a model of mycolic acid biosynthesis as well as on a genome-scale model of M. tuberculosis metabolism. Our method correctly predicts seven of the eight known fatty acid inhibitors in this compendium and makes accurate predictions regarding the specificity of these compounds for fatty acid biosynthesis. Our method also predicts a number of additional potential modulators of TB mycolic acid biosynthesis. E-Flux thus provides a promising new approach for algorithmically predicting metabolic state from gene expression data.

  4. Fatal malonyl CoA decarboxylase deficiency due to maternal uniparental isodisomy of the telomeric end of chromosome 16.

    Science.gov (United States)

    Malvagia, S; Papi, L; Morrone, A; Donati, M A; Ciani, F; Pasquini, E; la Marca, G; Scholte, H R; Genuardi, M; Zammarchi, E

    2007-11-01

    Malonic aciduria is a rare autosomal recessive disorder caused by deficiency of malonyl-CoA decarboxylase, encoded by the MLYCD gene. We report on a patient with clinical presentation in the neonatal period. Metabolic investigations led to a diagnosis of malonyl-CoA decarboxylase deficiency, confirmed by decreased activity in cultured fibroblasts. High doses of carnitine and a diet low in lipids led to a reduction in malonic acid excretion, and to an improvement in his clinical conditions, but at the age of 4 months he died suddenly and unexpectedly. No autopsy was performed. Molecular analysis of the MLYCD gene performed on the proband's RNA and genomic DNA identified a previously undescribed mutation (c.772-775delACTG) which was homozygous. This mutation was present in his mother but not in his father; paternity was confirmed by microsatellite analysis. A hypothesis of maternal uniparental disomy (UPD) was investigated using fourteen microsatellite markers on chromosome 16, and the results confirmed maternal UPD. Maternal isodisomy of the 16q24 region led to homozygosity for the MLYCD mutant allele, causing the patient's disease. These findings are relevant for genetic counselling of couples with a previously affected child, since the recurrence risk in future pregnancies is dramatically reduced by the finding of UPD. In addition, since the patient had none of the clinical manifestations previously associated with maternal UPD 16, this case provides no support for the existence of maternally imprinted genes on chromosome 16 with a major effect on phenotype.

  5. Short Chain Fatty Acids (SCFA) Reprogram Gene Expression in Human Malignant Epithelial and Lymphoid Cells

    OpenAIRE

    Lidiia Astakhova; Mtakai Ngara; Olga Babich; Aleksandr Prosekov; Lyudmila Asyakina; Lyubov Dyshlyuk; Tore Midtvedt; Xiaoying Zhou; Ingemar Ernberg; Liudmila Matskova

    2016-01-01

    The effect of short chain fatty acids (SCFAs) on gene expression in human, malignant cell lines was investigated, with a focus on signaling pathways. The commensal microbial flora produce high levels of SCFAs with established physiologic effects in humans. The most abundant SCFA metabolite in the human microflora is n-butyric acid. It is well known to activate endogenous latent Epstein-Barr virus (EBV), that was used as a reference read out system and extended to EBV+ epithelial cancer cell l...

  6. Effects of dietary protein and amino acid levels on the expression of selected cationic amino acid transporters and serum amino acid concentration in growing pigs.

    Science.gov (United States)

    García-Villalobos, Héctor; Morales-Trejo, Adriana; Araiza-Piña, Benedicto A; Htoo, John K; Cervantes-Ramírez, Miguel

    2012-08-01

    The absorption of lysine is facilitated by leucine, but there is no information regarding the effect of crude protein, lysine and leucine levels on the expression of cationic amino acid transporters in pigs. Therefore, an experiment was conducted with 20 pigs (14.9 +/- 0.62 kg initial body weight) to evaluate the effect of two protein levels, and the content of lysine, threonine, methionine and leucine in low crude protein diets on the expression of b(0,+) and CAT-1 mRNA in jejunum, Longissimus dorsi and Semitendinosus muscles and serum concentration of amino acids. Treatments were as follows: (i) wheat-soybean meal diet, 20% crude protein (Control); (ii) wheat diet deficient in lysine, threonine and methionine (Basal diet); (iii) Basal diet plus 0.70% L-lysine, 0.27% L-threonine, 0.10% DL-methionine (Diet LTM); (iv) Diet LTM plus 0.80% L-leucine (Diet LTM + Leu). Despite the Basal diet, all diets were formulated to meet the requirements of lysine, threonine and methionine; Diet LTM + Leu supplied 60% excess of leucine. The addition of lysine, threonine and methionine in Diet LTM increased the expression of b(0,+) in jejunum and CAT-1 in the Semitendinosus and Longissiums muscles and decreased CAT-1 in jejunum; the serum concentration of lysine was also increased (p Pigs fed the Control diet expressed less b(0,+) in jejunum, and CAT-1 in the Semitendinosus and Longissiums muscles expressed more CAT-1 in jejunum (p dietary amino acids, affect the expression of cationic amino acid transporters in pigs fed wheat-based diets.

  7. Enhanced succinic acid production in Aspergillus saccharolyticus by heterologous expression of fumarate reductase from Trypanosoma brucei.

    Science.gov (United States)

    Yang, Lei; Lübeck, Mette; Ahring, Birgitte K; Lübeck, Peter S

    2016-02-01

    Aspergillus saccharolyticus exhibits great potential as a cell factory for industrial production of dicarboxylic acids. In the analysis of the organic acid profile, A. saccharolyticus was cultivated in an acid production medium using two different pH conditions. The specific activities of the enzymes, pyruvate carboxylase (PYC), malate dehydrogenase (MDH), and fumarase (FUM), involved in the reductive tricarboxylic acid (rTCA) branch, were examined and compared in cells harvested from the acid production medium and a complete medium. The results showed that ambient pH had a significant impact on the pattern and the amount of organic acids produced by A. saccharolyticus. The wild-type strain produced higher amount of malic acid and succinic acid in the pH buffered condition (pH 6.5) compared with the pH non-buffered condition. The enzyme assays showed that the rTCA branch was active in the acid production medium as well as the complete medium, but the measured enzyme activities were different depending on the media. Furthermore, a soluble NADH-dependent fumarate reductase gene (frd) from Trypanosoma brucei was inserted and expressed in A. saccharolyticus. The expression of the frd gene led to an enhanced production of succinic acid in frd transformants compared with the wild-type in both pH buffered and pH non-buffered conditions with highest amount produced in the pH buffered condition (16.2 ± 0.5 g/L). This study demonstrates the feasibility of increasing succinic acid production through the cytosolic reductive pathway by genetic engineering in A. saccharolyticus.

  8. Expression analysis for genes involved in arachidonic acid biosynthesis in Mortierella alpina CBS 754.68

    Directory of Open Access Journals (Sweden)

    Hamid-Reza Samadlouie

    2014-06-01

    Full Text Available The time courses for production of fungal biomass, lipid, phenolic and arachidonic acid (ARA as well as expression of the genes involved in biosynthesis of ARA and lipid were examined in Mortierella alpina CBS 754.68. A significant increase in the arachidonic acid content in lipids that coincided with reduced levels of lipid was obtained. Reduced gene expression occurred presumably due to the steady reduction of carbon and nitrogen resources. However, these energy resources were inefficiently compensated by the breakdown of the accumulated lipids that in turn, induced up-regulated expression of the candidate genes. The results further indicated that the expression of the GLELO encoding gene is a rate-limiting step in the biosynthesis of ARA in the early growth phase.

  9. Development of a detection system for histidine decarboxylating lactic acid bacteria based on DNA probes, PCR and activity test

    NARCIS (Netherlands)

    Le Jeune, C.; Lonvaud-Funel, A.; Brink, B. ten; Hofstra, H.; Vossen, J.M.B.M. van der

    1995-01-01

    On the basis of the comparison of the nucleotide sequences of the histidine decarboxylase genes (hdcA) of Lactobacillus 30A and Clostridium perfringens and the amino acid sequences of these histidine decarboxylases and those of Lactobacillus buchneri and Micrococcus, oligonucleotides unique to the h

  10. Structure-dependent effects of pyridine derivatives on mechanisms of intestinal fatty acid uptake: regulation of nicotinic acid receptor and fatty acid transporter expression.

    Science.gov (United States)

    Riedel, Annett; Lang, Roman; Rohm, Barbara; Rubach, Malte; Hofmann, Thomas; Somoza, Veronika

    2014-07-01

    Pyridines are widely distributed in foods. Nicotinic acid (NA), a carboxylated pyridine derivative, inhibits lipolysis in adipocytes by activation of the orphan NA receptor (HM74A) and is applied to treat hyperlipidemia. However, knowledge on the impact of pyridine derivatives on intestinal lipid metabolism is scarce. This study was performed to identify the structural determinants of pyridines for their effects on fatty acid uptake in enterocyte-like Caco-2 cells and to elucidate the mechanisms of action. The impact of 17 pyridine derivatives on fatty acid uptake was tested. Multiple regression analysis revealed the presence of a methyl group to be the structural determinant at 0.1 mM, whereas at 1 mM, the presence of a carboxylic group and the N-methylation presented further structural characteristics to affect the fatty acid uptake. NA, showing a stimulating effect on FA uptake, and N-methyl-4-phenylpyridinium (MPP), inhibiting FA uptake, were selected for mechanistic studies. Gene expression of the fatty acid transporters CD36, FATP2 and FATP4, and the lipid metabolism regulating transcription factors peroxisome proliferator-activated receptor (PPAR) α and PPARγ was up-regulated upon NA treatment. Caco-2 cells were demonstrated to express the low-affinity NA receptor HM74 of which the gene expression was up-regulated upon NA treatment. We hypothesize that the NA-induced fatty acid uptake might result from NA receptor activation and related intracellular signaling cascades. In contrast, MPP increased transepithelial electrical resistance. We therefore conclude that NA and MPP, both sharing the pyridine motif core, exhibit their contrary effects on intestinal FA uptake by activation of different mechanisms.

  11. Ornithine decarboxylase antizyme finder (OAF: Fast and reliable detection of antizymes with frameshifts in mRNAs

    Directory of Open Access Journals (Sweden)

    Atkins John F

    2008-04-01

    Full Text Available Abstract Background Ornithine decarboxylase antizymes are proteins which negatively regulate cellular polyamine levels via their affects on polyamine synthesis and cellular uptake. In virtually all organisms from yeast to mammals, antizymes are encoded by two partially overlapping open reading frames (ORFs. A +1 frameshift between frames is required for the synthesis of antizyme. Ribosomes change translation phase at the end of the first ORF in response to stimulatory signals embedded in mRNA. Since standard sequence analysis pipelines are currently unable to recognise sites of programmed ribosomal frameshifting, proper detection of full length antizyme coding sequences (CDS requires conscientious manual evaluation by a human expert. The rapid growth of sequence information demands less laborious and more cost efficient solutions for this problem. This manuscript describes a rapid and accurate computer tool for antizyme CDS detection that requires minimal human involvement. Results We have developed a computer tool, OAF (ODC antizyme finder for identifying antizyme encoding sequences in spliced or intronless nucleic acid sequenes. OAF utilizes a combination of profile hidden Markov models (HMM built separately for the products of each open reading frame constituting the entire antizyme coding sequence. Profile HMMs are based on a set of 218 manually assembled antizyme sequences. To distinguish between antizyme paralogs and orthologs from major phyla, antizyme sequences were clustered into twelve groups and specific combinations of profile HMMs were designed for each group. OAF has been tested on the current version of dbEST, where it identified over six thousand Expressed Sequence Tags (EST sequences encoding antizyme proteins (over two thousand antizyme CDS in these ESTs are non redundant. Conclusion OAF performs well on raw EST sequences and mRNA sequences derived from genomic annotations. OAF will be used for the future updates of the RECODE

  12. Detailed transcriptomics analysis of the effect of dietary fatty acids on gene expression in the heart.

    Science.gov (United States)

    Georgiadi, Anastasia; Boekschoten, Mark V; Müller, Michael; Kersten, Sander

    2012-03-19

    Fatty acids comprise the primary energy source for the heart and are mainly taken up via hydrolysis of circulating triglyceride-rich lipoproteins. While most of the fatty acids entering the cardiomyocyte are oxidized, a small portion is involved in altering gene transcription to modulate cardiometabolic functions. So far, no in vivo model has been developed enabling study of the transcriptional effects of specific fatty acids in the intact heart. In the present study, mice were given a single oral dose of synthetic triglycerides composed of one single fatty acid. Hearts were collected 6 h thereafter and used for whole genome gene expression profiling. Experiments were conducted in wild-type and peroxisome proliferator-activated receptor (PPAR)α-/- mice to allow exploration of the specific contribution of PPARα. It was found that: 1) C18:3 had the most pronounced effect on cardiac gene expression. 2) The largest similarity in gene regulation was observed between C18:2 and C18:3. Large similarity was also observed between PPARα agonist Wy14643 and C22:6. 3) Many genes were regulated by one particular treatment only. Genes regulated by one particular treatment showed large functional divergence. 4) The majority of genes responding to fatty acid treatment were regulated in a PPARα-dependent manner, emphasizing the importance of PPARα in mediating transcriptional regulation by fatty acids in the heart. 5) Several genes were robustly regulated by all or many of the fatty acids studied, mostly representing well-described targets of PPARs (e.g., Acot1, Angptl4, Ucp3) but also including Zbtb16/PLZF, a transcription factor crucial for natural killer T cell function. 6) Deletion and activation of PPARα had a major effect on expression of numerous genes involved in metabolism and immunity. Our analysis demonstrates the marked impact of dietary fatty acids on gene regulation in the heart via PPARα.

  13. Molecular cloning and ontogenesis expression of fatty acid transport protein-1 in yellow-feathered broilers

    Institute of Scientific and Technical Information of China (English)

    Yuzhen Song; Jiaying Feng; Lihua Zhou; Gang Shu; Xiaotong Zhu; Ping Gao; Yongliang Zhang; Qingyan Jiang

    2008-01-01

    Fatty acid transport protein-1 (FATP-1) is one of the important transporter proteins involved in fatty acid transmembrane transport and fat deposition. To study the relationship between FATP-1 mRNA expression and fat deposition, chicken (Gallus gallus) FATP-1 sequence was first cloned by rapid amplification of cDNA ends (RACE). Tissue samples of chest muscle, leg muscle, subcutaneous fat, and abdominal fat were collected from six male and six female broilers each, at 22 days, 29 days, and 42 days, respectively. The tissue specificity and ontogenesis expression pattern of the FATP-1 mRNA of yellow-feathered broilers was studied by real-time reverse transcription polymerase chain reaction (RT-PCR), and the fat deposition laws in different tissues were also compared. A 2,488 bp cDNA sequence of chicken FATP-1 was cloned by RACE (GenBank accession no. DQ352834), including 547 bp 3' end untranslated region (URT) and 1,941 bp open reading frame (ORF). Chicken FATP-1 encoded 646 amino acid residues, which shared 83.9% and 83.0% identity with those of human and rat, respectively. The results of quantitative PCR demonstrated a constant FATP-1 mRNA expression level in the chest muscle and subcutaneous fat of both male and female broilers at three stages, whereas the expression level of the FATP-1 mRNA in the leg muscle at 42 days was significantly higher than that at 22 days or 29 days. In the abdominal fat of male broilers, the gene expression significantly increased with age, whereas the female broilers showed a dramatic downregulation of FATP-1 expression in abdominal fat at 42 days. This suggested a typical tissue-and gender-specific expression pattern of chicken FATP-1, mediating the specific process of fatty acid transport or utilization in muscle and adipose tissues.

  14. Human intestine luminal ACE2 and amino acid transporter expression increased by ACE-inhibitors.

    Science.gov (United States)

    Vuille-dit-Bille, Raphael N; Camargo, Simone M; Emmenegger, Luca; Sasse, Tom; Kummer, Eva; Jando, Julia; Hamie, Qeumars M; Meier, Chantal F; Hunziker, Schirin; Forras-Kaufmann, Zsofia; Kuyumcu, Sena; Fox, Mark; Schwizer, Werner; Fried, Michael; Lindenmeyer, Maja; Götze, Oliver; Verrey, François

    2015-04-01

    Sodium-dependent neutral amino acid transporter B(0)AT1 (SLC6A19) and imino acid (proline) transporter SIT1 (SLC6A20) are expressed at the luminal membrane of small intestine enterocytes and proximal tubule kidney cells where they exert key functions for amino acid (re)absorption as documented by their role in Hartnup disorder and iminoglycinuria, respectively. Expression of B(0)AT1 was shown in rodent intestine to depend on the presence of the carboxypeptidase angiotensin-converting enzyme 2 (ACE2). This enzyme belongs to the renin-angiotensin system and its expression is induced by treatment with ACE-inhibitors (ACEIs) or angiotensin II AT1 receptor blockers (ARBs) in many rodent tissues. We show here in the Xenopus laevis oocyte expression system that human ACE2 also functionally interacts with SIT1. To investigate in human intestine the potential effect of ACEIs or ARBs on ACE2, we analysed intestinal biopsies taken during routine gastroduodenoscopy and ileocolonoscopy from 46 patients of which 9 were under ACEI and 13 ARB treatment. Analysis of transcript expression by real-time PCR and of proteins by immunofluorescence showed a co-localization of SIT1 and B(0)AT1 with ACE2 in the brush-border membrane of human small intestine enterocytes and a distinct axial expression pattern of the tested gene products along the intestine. Patients treated with ACEIs displayed in comparison with untreated controls increased intestinal mRNA levels of ACE2, peptide transporter PEPT1 (SLC15A1) and AA transporters B(0)AT1 and PAT1 (SLC36A1). This study unravels in human intestine the localization and distribution of intestinal transporters involved in amino acid absorption and suggests that ACEIs impact on their expression.

  15. Fatty acid transport protein expression in human brain and potential role in fatty acid transport across human brain microvessel endothelial cells.

    Science.gov (United States)

    Mitchell, Ryan W; On, Ngoc H; Del Bigio, Marc R; Miller, Donald W; Hatch, Grant M

    2011-05-01

    The blood-brain barrier (BBB), formed by the brain capillary endothelial cells, provides a protective barrier between the systemic blood and the extracellular environment of the CNS. Passage of fatty acids from the blood to the brain may occur either by diffusion or by proteins that facilitate their transport. Currently several protein families have been implicated in fatty acid transport. The focus of the present study was to identify the fatty acid transport proteins (FATPs) expressed in the brain microvessel endothelial cells and characterize their involvement in fatty acid transport across an in vitro BBB model. The major fatty acid transport proteins expressed in human brain microvessel endothelial cells (HBMEC), mouse capillaries and human grey matter were FATP-1, -4 and fatty acid binding protein 5 and fatty acid translocase/CD36. The passage of various radiolabeled fatty acids across confluent HBMEC monolayers was examined over a 30-min period in the presence of fatty acid free albumin in a 1 : 1 molar ratio. The apical to basolateral permeability of radiolabeled fatty acids was dependent upon both saturation and chain length of the fatty acid. Knockdown of various fatty acid transport proteins using siRNA significantly decreased radiolabeled fatty acid transport across the HBMEC monolayer. Our findings indicate that FATP-1 and FATP-4 are the predominant fatty acid transport proteins expressed in the BBB based on human and mouse expression studies. While transport studies in HBMEC monolayers support their involvement in fatty acid permeability, fatty acid translocase/CD36 also appears to play a prominent role in transport of fatty acids across HBMEC.

  16. Regulation of the expression of key genes involved in HDL metabolism by unsaturated fatty acids

    Science.gov (United States)

    The aim of this study was to determine the effects, and possible mechanisms of action, of unsaturated fatty acids on the expression of genes involved in HDL metabolism in HepG2 cells. The mRNA concentration of target genes was assessed by real time PCR. Protein concentrations were determined by wes...

  17. Expression patterns of nicotinamide phosphoribosyltransferase and nicotinic acid phosphoribosyltransferase in human malignant lymphomas

    DEFF Research Database (Denmark)

    Olesen, Uffe Høgh; Hastrup, Nina; Sehested, Maxwell

    2011-01-01

    The purpose of the study was to determine in human malignant lymphomas the expression patterns of nicotinamide phosphoribosyltransferase (NAMPT) and nicotinic acid phosphoribosyltransferase (NAPRT), the primary, rate-limiting enzymes in the synthesis of NAD+. NAMPT is a potential biomarker for se...

  18. Expression patterns of glial fibrillary acidic protein (GFAP)-delta in epilepsy-associated lesional pathologies

    NARCIS (Netherlands)

    L. Martinian; K. Boer; J. Middeldorp; E.M. Hol; S.M. Sisodiya; W. Squier; E.M.A. Aronica; M. Thom

    2009-01-01

    Aims: Glial fibrillary acidic protein (GFAP)-delta is a novel isoform that differs in its C-terminal sequence from other GFAP isoforms. Previous studies suggest restriction of expression to the subpial layer, subventricular zone and the subgranular zone astrocytes, with an absence in pathological co

  19. GPBAR1/TGR5 mediates bile acid-induced cytokine expression in murine Kupffer cells.

    Directory of Open Access Journals (Sweden)

    Guiyu Lou

    Full Text Available GPBAR1/TGR5 is a novel plasma membrane-bound G protein-coupled bile acid (BA receptor. BAs are known to induce the expression of inflammatory cytokines in the liver with unknown mechanism. Here we show that without other external stimuli, TGR5 activation alone induced the expression of interleukin 1β (IL-1β and tumor necrosis factor-α (TNF-α in murine macrophage cell line RAW264.7 or murine Kupffer cells. The TGR5-mediated increase of pro-inflammatory cytokine expression was suppressed by JNK inhibition. Moreover, the induced pro-inflammatory cytokine expression in mouse liver by 1% cholic acid (CA diet was blunted in JNK-/- mice. TGR5 activation by its ligands enhanced the phosphorylation levels, DNA-binding and trans-activities of c-Jun and ATF2 transcription factors. Finally, the induced pro-inflammatory cytokine expression in Kupffer cells by TGR5 activation correlated with the suppression of Cholesterol 7α-hydroxylase (Cyp7a1 expression in murine hepatocytes. These results suggest that TGR5 mediates the BA-induced pro-inflammatory cytokine production in murine Kupffer cells through JNK-dependent pathway. This novel role of TGR5 may correlate to the suppression of Cyp7a1 expression in hepatocytes and contribute to the delicate BA feedback regulation.

  20. Acidic duodenal pH alters gene expression in the cystic fibrosis mouse pancreas.

    Science.gov (United States)

    Kaur, Simran; Norkina, Oxana; Ziemer, Donna; Samuelson, Linda C; De Lisle, Robert C

    2004-08-01

    The duodenum is abnormally acidic in cystic fibrosis (CF) due to decreased bicarbonate ion secretion that is dependent on the CF gene product CFTR. In the CFTR null mouse, the acidic duodenum results in increased signaling from the intestine to the exocrine pancreas in an attempt to stimulate pancreatic bicarbonate ion secretion. Excess stimulation is proposed to add to the stress/inflammation of the pancreas in CF. DNA microarray analysis of the CF mouse revealed altered pancreatic gene expression characteristic of stress/inflammation. When the duodenal pH was corrected genetically (crossing CFTR null with gastrin null mice) or pharmacologically (use of the proton pump inhibitor omeprazole), expression levels of genes measured by quantitative RT-PCR were significantly normalized. It is concluded that the acidic duodenal pH in CF contributes to the stress on the exocrine pancreas and that normalizing duodenal pH reduces this stress.

  1. Imaging Cancer Cells Expressing the Folate Receptor with Carbon Dots Produced from Folic Acid.

    Science.gov (United States)

    Bhunia, Susanta Kumar; Maity, Amit Ranjan; Nandi, Sukhendu; Stepensky, David; Jelinek, Raz

    2016-04-01

    Development of new imaging tools for cancer cells in vitro and in vitro is important for advancing cancer research, elucidating drug effects upon cancer cells, and studying cellular processes. We showed that fluorescent carbon dots (C-dots) synthesized from folic acid can serve as an effective vehicle for imaging cancer cells expressing the folate receptor on their surface. The C-dots, synthesized through a simple one-step process from folic acid as the carbon source, exhibited selectivity towards cancer cells displaying the folate receptor, making such cells easily distinguishable in fluorescence microscopy imaging. Biophysical measurements and competition experiments both confirmed the specific targeting and enhanced uptake of C-dots by the folate receptor-expressing cells. The folic acid-derived C-dots were not cytotoxic, and their use in bioimaging applications could aid biological studies of cancer cells, identification of agonists/antagonists, and cancer diagnostics.

  2. An acid phosphatase locus expressed in mouse kidney (Apk) and its genetic location on chromosome 10.

    Science.gov (United States)

    Womack, J E; Auerbach, S B

    1978-04-01

    A genetic locus controlling the electrophoretic mobility of an acid phosphatase in mouse kidney is described. This locus, called acid phosphatase-kidney (Apk), is not expressed in erythrocytes, liver, spleen, heart, lung, brain, skeletal muscle, stomach, or testes. The product of Apk hydrolyzes the substrate naphthol AS-MX phosphoric acid but is not active on alpha-naphthylphosphate or 4-methylumbelliferylphosphate. It is not inactivated by 50 C for 1 hr, nor is its electrophoretic mobility altered by incubation with neuraminidase. The locus is invariant among 31 inbred strains (Apka), with a variant allele (Apkm) observed only in Mus musculus molossinus. Codominant expression was observed in F1 hybrids of M. m. molossinus and inbred strains. Apk was mapped on Chr 10, near the neurological mutant waltzer (v).

  3. Activation of Hepatic Lipase Expression by Oleic Acid: Possible Involvement of USF1

    Directory of Open Access Journals (Sweden)

    Adrie J. M. Verhoeven

    2009-10-01

    Full Text Available Polyunsaturated fatty acids affect gene expression mainly through peroxisome proliferator-activated receptors (PPARs and sterol regulatory element binding proteins (SREBPs, but how monounsaturated fatty acids affect gene expression is poorly understood. In HepG2 cells, oleate supplementation has been shown to increase secretion of hepatic lipase (HL. We hypothesized that oleate affects HL gene expression at the transcriptional level. To test this, we studied the effect of oleate on HL promoter activity using HepG2 cells and the proximal HL promoter region (700 bp. Oleate increased HL expression and promoter activity 1.3–2.1 fold and reduced SREBP activity by 50%. Downregulation of SREBP activity by incubation with cholesterol+25-hydroxycholesterol had no effect on HL promoter activity. Overexpression of SREBP2, but not SREBP1, reduced HL promoter activity, which was effected mainly through the USF1 binding site at -307/-312. Oleate increased the nuclear abundance of USF1 protein 2.7 ± 0.6 fold, while USF1 levels were reduced by SREBP2 overexpression. We conclude that oleate increases HL gene expression via USF1. USF1 may be an additional fatty acid sensor in liver cells.

  4. Megalin and cubilin expression in gallbladder epithelium and regulation by bile acids.

    Science.gov (United States)

    Erranz, Benjamín; Miquel, Juan Francisco; Argraves, W Scott; Barth, Jeremy L; Pimentel, Fernando; Marzolo, María-Paz

    2004-12-01

    Cholesterol crystal formation in the gallbladder is a key step in gallstone pathogenesis. Gallbladder epithelial cells might prevent luminal gallstone formation through a poorly understood cholesterol absorption process. Genetic studies in mice have highlighted potential gallstone susceptibility alleles, Lith genes, which include the gene for megalin. Megalin, in conjunction with the large peripheral membrane protein cubilin, mediates the endocytosis of numerous ligands, including HDL/apolipoprotein A-I (apoA-I). Although the bile contains apoA-I and several cholesterol-binding megalin ligands, the expression of megalin and cubilin in the gallbladder has not been investigated. Here, we show that both proteins are expressed by human and mouse gallbladder epithelia. In vitro studies using a megalin-expressing cell line showed that lithocholic acid strongly inhibits and cholic and chenodeoxycholic acids increase megalin expression. The effects of bile acids (BAs) were also demonstrated in vivo, analyzing gallbladder levels of megalin and cubilin from mice fed with different BAs. The BA effects could be mediated by the farnesoid X receptor, expressed in the gallbladder. Megalin protein was also strongly increased after feeding a lithogenic diet. These results indicate a physiological role for megalin and cubilin in the gallbladder and provide support for a role for megalin in gallstone pathogenesis.

  5. Enhanced flux of substrates into polyamine biosynthesis but not ethylene in tomato fruit engineered with yeast S-adenosylmethionine decarboxylase gene.

    Science.gov (United States)

    Lasanajak, Yi; Minocha, Rakesh; Minocha, Subhash C; Goyal, Ravinder; Fatima, Tahira; Handa, Avtar K; Mattoo, Autar K

    2014-03-01

    S-adenosylmethionine (SAM), a major substrate in 1-C metabolism is a common precursor in the biosynthetic pathways of polyamines and ethylene, two important plant growth regulators, which exhibit opposing developmental effects, especially during fruit ripening. However, the flux of various substrates including SAM into the two competing pathways in plants has not yet been characterized. We used radiolabeled (14)C-Arg, (14)C-Orn, L-[U-(14)C]Met, (14)C-SAM and (14)C-Put to quantify flux through these pathways in tomato fruit and evaluate the effects of perturbing these pathways via transgenic expression of a yeast SAM decarboxylase (ySAMDC) gene using the fruit ripening-specific promoter E8. We show that polyamines in tomato fruit are synthesized both from Arg and Orn; however, the relative contribution of Orn pathway declines in the later stages of ripening. Expression of ySAMDC reversed the ripening associated decline in spermidine (Spd) and spermine (Spm) levels observed in the azygous control fruit. About 2- to 3-fold higher levels of labeled-Spd in transgenic fruit (556HO and 579HO lines) expressing ySAMDC confirmed the enzymatic function of the introduced gene. The incorporation of L-[U-(14)C]Met into Spd, Spm, ethylene and 1-aminocyclopropane-1-carboxylic acid (ACC) was used to determine Met-flux into these metabolites. The incorporation of (14)C-Met into Spd/Spm declined during ripening of the control azygous fruit but this was reversed in fruits expressing ySAMDC. However, incorporation of (14)C-Met into ethylene or ACC during ripening was not altered by the expression of ySAMDC in the fruit. Taken together these results show that: (1) There is an inverse relationship between the production of higher polyamines and ethylene during fruit ripening, (2) the inverse relationship between higher polyamines and ethylene is modulated by ySAMDC expression in that the decline in Spd/Spm during fruit ripening can be reversed without significantly altering ethylene

  6. Chlorophyll-derived fatty acids regulate expression of lipid metabolizing enzymes in liver - a nutritional opportunity

    Directory of Open Access Journals (Sweden)

    Wolfrum Christian

    2001-01-01

    Full Text Available Nutritional values of fatty acid classes are normally discussed on the basis of their saturated, monounsaturated and polyunsaturated structures with implicit understanding that they are straight-chain. Here we focus on chlorophyll-derived phytanic and pristanic acids that are minor isoprenoid branched-chain lipid constituents in food, but of unknown nutritional value. After describing the enzyme machinery that degrades these nutrient fatty acids in the peroxisome, we show by the criteria of a mouse model and of a human cell culture model that they induce with high potency expression of enzymes responsible for beta-oxidation of straight-chain fatty acids in the peroxisome. We summarize present mechanistic knowledge on fatty acid signaling to the nucleus, which involves protein/protein contacts between peroxisome proliferator activated receptor (PPAR and fatty acid binding protein (FABP. In this signaling event the branched-chain fatty acids are the most effective ones. Finally, on the basis of this nutrient-gene interaction we discuss nutritional opportunities and therapeutic aspects of the chlorophyll-derived fatty acids.

  7. Enzymatic Synthesis of Agmatine by Immobilized Escherichia coli Cells with Arginine Decarboxylase Activity

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wei-guo; ZHAO Gen-hai; LIU Jun-zhong; LIU Qian; JIAO Qing-cai

    2011-01-01

    A new method for the enzymatic synthesis of agmatine by immobilized Escherichia coli cells with arginine decarboxylase(ADC)activity was established and a series of optimal reaction conditions was set down.The arginine decarboxylase showed the maximum activity when the pyridoxal phosphate(PLP)concentration was 50 mmol/L,pH=7 and 45 ℃.The arginine decarboxylase exhibited the maximum production efficiency when the substrate concentration was 100 mmol/L and the reaction time was 15 h.It was also observed that the appropriate concentration of Mg2+,especially at 0.5 mmol/L promoted the arginine decarboxylase activity; Mn2+ had little effect on the arginine decarboxylase activity.The inhibition of Cu2+ and Zn2+ to the arginine decarboxylase activity was significant.The immobilized cells were continuously used 6 times and the average conversion rate during the six-time usage was 55.6%.The immobilized cells exhibited favourable operational stability.After optimization,the maximally cumulative amount of agmatine could be up to 20 g/L.In addition,this method can also catalyze D,L-arginine to agmatine,leaving the pure optically D-arginine simultaneously.The method has a very important guiding significance to the enzymatic preparation of agmatine.

  8. Co-expression Analysis Identifies CRC and AP1 the Regulator of Arabidopsis Fatty Acid Biosynthesis

    Institute of Scientific and Technical Information of China (English)

    Xinxin Han; Linlin Yin; Hongwei Xue

    2012-01-01

    Fatty acids (FAs) play crucial rules in signal transduction and plant development,however,the regulation of FA metabolism is still poorly understood.To study the relevant regulatory network,fifty-eight FA biosynthesis genes including de novo synthases,desaturases and elongases were selected as "guide genes" to construct the co-expression network.Calculation of the correlation between all Arabidopsis thaliana (L.) genes with each guide gene by Arabidopsis co-expression dating mining tools (ACT)identifies 797 candidate FA-correlated genes.Gene ontology (GO) analysis of these co-expressed genes showed they are tightly correlated to photosynthesis and carbohydrate metabolism,and function in many processes.Interestingly,63 transcription factors (TFs) were identified as candidate FA biosynthesis regulators and 8 TF families are enriched.Two TF genes,CRC and AP1,both correlating with 8 FA guide genes,were further characterized.Analyses of the ap1 and crc mutant showed the altered total FA composition of mature seeds.The contents of palmitoleic acid,stearic acid,arachidic acid and eicosadienoic acid are decreased,whereas that of oleic acid is increased in ap1 and crc seeds,which is consistent with the qRT-PCR analysis revealing the suppressed expression of the corresponding guide genes.In addition,yeast one-hybrid analysis and electrophoretic mobility shift assay (EMSA) revealed that CRC can bind to the promoter regions of KCS7 and KCS15,indicating that CRC may directly regulate FA biosynthesis.

  9. Enzyme Architecture: The Activating Oxydianion Binding Domain for Orotidine 5′-Monophophate Decarboxylase

    Science.gov (United States)

    Spong, Krisztina; Amyes, Tina L.; Richard, John P.

    2014-01-01

    Orotidine 5′-monophosphate decarboxylase catalyzes the decarboxylation of truncated substrate (1-β-D-erythrofuranosyl)orotic acid (EO) to form (1-β-D-erythrofuranosyl)uracil (EU). This enzymecatalyzed reaction is activated by tetrahedral oxydianions, which bind weakly to unliganded OMPDC and tightly to the enzyme-transition state complex, with the following intrinsic oxydianion binding energies (kcal/mole): SO32−, −8.3; HPO32−, −7.7; S2O32−, −4.6; SO42−, −4.5; HOPO32−, −3.0; HOAsO32−, no activation detected. We propose that oxydianion and orotate binding domains perform complementary functions in catalysis of decarboxylation reactions. (1) The orotate binding domain carries out decarboxylation of the orotate ring. (2) The activating oxydianion binding domain has the cryptic function of utilizing binding interactions with tetrahedral inorganic oxydianions to drive an enzyme conformational change that results in the stabilization of transition states at the distant orotate domain. PMID:24274746

  10. Enzyme architecture: the activating oxydianion binding domain for orotidine 5'-monophophate decarboxylase.

    Science.gov (United States)

    Spong, Krisztina; Amyes, Tina L; Richard, John P

    2013-12-11

    Orotidine 5'-monophosphate decarboxylase catalyzes the decarboxylation of truncated substrate (1-β-D-erythrofuranosyl)orotic acid to form (1-β-D-erythrofuranosyl)uracil. This enzyme-catalyzed reaction is activated by tetrahedral oxydianions, which bind weakly to unliganded OMPDC and tightly to the enzyme-transition state complex, with the following intrinsic oxydianion binding energies (kcal/mol): SO3(2-), -8.3; HPO3(2-), -7.7; S2O3(2-), -4.6; SO4(2-), -4.5; HOPO3(2-), -3.0; HOAsO3(2-), no activation detected. We propose that the oxydianion and orotate binding domains of OMPDC perform complementary functions in catalysis of decarboxylation reactions: (1) The orotate binding domain carries out decarboxylation of the orotate ring. (2) The activating oxydianion binding domain has the cryptic function of utilizing binding interactions with tetrahedral inorganic oxydianions to drive an enzyme conformational change that results in the stabilization of transition states at the distant orotate domain.

  11. Molecular characterization of Mtb-OMP decarboxylase by modeling, docking and dynamic studies.

    Science.gov (United States)

    Madhusudana, P; Babajan, B; Chaitanya, M; Anuradha, C M; Shobharani, C; Chikati, Rajasekar; Kumar, Chitta Suresh; Rao, K R S Sambasiva; Poda, Sudhakar

    2012-06-01

    Tuberculosis (TB), the second most deadly disease in the world is caused by Mycobacterium tuberculosis (Mtb). In the present work a unique enzyme of Mtb orotidine 5' monophosphate decarboxylase (Mtb-OMP Decase) is selected as drug target due to its indispensible role in biosynthesis of pyrimidines. The present work is focused on understanding the structural and functional aspects of Mtb-OMP Decase at molecular level. Due to absence of crystal structure, the 3D structure of Mtb-OMP Decase was predicted by MODELLER9V7 using a known structural template 3L52. Energy minimization and refinement of the developed 3D model was carried out with Gromacs 3.2.1 and the optimized homology model was validated by PROCHECK,WHAT-IF and PROSA2003. Further, the surface active site amino acids were quantified by WHAT-IF pocket. The exact binding interactions of the ligands, 6-idiouridine 5' monophosphate and its designed analogues with the receptor Mtb-OMP Decase were predicted by docking analysis with AUTODOCK 4.0. This would be helpful in understanding the blockade mechanism of OMP Decase and provide a candidate lead for the discovery of Mtb-OMP Decase inhibitors, which may bring insights into outcome new therapy to treat drug resistant Mtb.

  12. Nucleotide variation at the dopa decarboxylase (Ddc) gene in natural populations of Drosophila melanogaster

    Indian Academy of Sciences (India)

    Andrey Tatarenkov; Francisco J. Ayala

    2007-08-01

    We studied nucleotide sequence variation at the gene coding for dopa decarboxylase (Ddc) in seven populations of Drosophila melanogaster. Strength and pattern of linkage disequilibrium are somewhat distinct in the extensively sampled Spanish and Raleigh populations. In the Spanish population, a few sites are in strong positive association, whereas a large number of sites in the Raleigh population are associated nonrandomly but the association is not strong. Linkage disequilibrium analysis shows presence of two groups of haplotypes in the populations, each of which is fairly diverged, suggesting epistasis or inversion polymorphism. There is evidence of two forms of natural selection acting on Ddc. The McDonald–Kreitman test indicates a deficit of fixed amino acid differences between D. melanogaster and D. simulans, which may be due to negative selection. An excess of derived alleles at high frequency, significant according to the -test, is consistent with the effect of hitchhiking. The hitchhiking may have been caused by directional selection downstream of the locus studied, as suggested by a gradual decrease of the polymorphism-to-divergence ratio. Altogether, the Ddc locus exhibits a complicated pattern of variation apparently due to several evolutionary forces. Such a complex pattern may be a result of an unusually high density of functionally important genes.

  13. Myristic Acid (MA) Promotes Adipogenic Gene Expression and the Differentiation of Porcine Intramuscular Adipocyte Precursor Cells

    Institute of Scientific and Technical Information of China (English)

    LU Nai-sheng; ZHANG Yong-liang; JIANG Qing-yan; SHU Gang; XIE Qiu-ping; ZHU Xiao-tong; GAO Ping; ZHOU Gui-xuan; WANG Song-bo; WANG Li-na; XI Qian-yun

    2014-01-01

    Intramuscular fat (IMF) content is considered to be a key factor that affects the marbling, tenderness, juiciness and lfavor of pork. To investigate the effects of myristic acid (MA) on the differentiation of porcine intramuscular adipocytes, cells were isolated from longissimus dorsi muscle (LDM) and treated with 0, 10, 50 or 100μmol L-1 MA. The results showed that MA signiifcantly promotes the differentiation of intramuscular adipocytes in a dose-dependent manner. MA also led to a parallel increase in the expression of peroxisome proliferator activated receptor-γ(PPARγ) and adipose-related genes, such as glucose transporter 1 (GLUT1), lipoprotein lipase (LPL), adipocyte fatty acid binding protein 4 (FABP4/aP2), fatty acid translocase (FAT), acetyl-CoA carboxylaseα(ACCα), adipose triglyceride lipase (ATGL) and fatty acid synthase (FASN). However, no signiifcant effects of MA were observed on the expression of CAAT enhancer binding protein-α(C/EBPα) or hormone sensitive lipase (HSL). The expression of pyruvate dehydrogenase kinase 4 (PDK4) was increased by MA during the early stages of differentiation (day 1-3). In addition, MA also increased the absolute content of C14 (P<0.001) and saturated fatty acids (SFA) (P<0.05) to varying degrees, but no effects were observed on other fatty acids. These results suggest that MA might be able to enhance the IMF content of pork and increase the accumulation of myristic and myristoleic acid in muscle, which might have beneifcial implications for human health.

  14. Engineering pyruvate decarboxylase-mediated ethanol production in the thermophilic host Geobacillus thermoglucosidasius.

    Science.gov (United States)

    Van Zyl, L J; Taylor, M P; Eley, K; Tuffin, M; Cowan, D A

    2014-02-01

    This study reports the expression, purification, and kinetic characterization of a pyruvate decarboxylase (PDC) from Gluconobacter oxydans. Kinetic analyses showed the enzyme to have high affinity for pyruvate (120 μM at pH 5), high catalytic efficiency (4.75 × 10(5) M(-1) s(-1) at pH 5), a pHopt of approximately 4.5 and an in vitro temperature optimum at approximately 55 °C. Due to in vitro thermostablity (approximately 40 % enzyme activity retained after 30 min at 65 °C), this PDC was considered to be a suitable candidate for heterologous expression in the thermophile Geobacillus thermoglucosidasius for ethanol production. Initial studies using a variety of methods failed to detect activity at any growth temperature (45-55 °C). However, the application of codon harmonization (i.e., mimicry of the heterogeneous host's transcription and translational rhythm) yielded a protein that was fully functional in the thermophilic strain at 45 °C (as determined by enzyme activity, Western blot, mRNA detection, and ethanol productivity). Here, we describe the first successful expression of PDC in a true thermophile. Yields as high as 0.35 ± 0.04 g/g ethanol per gram of glucose consumed were detected, highly competitive to those reported in ethanologenic thermophilic mutants. Although activities could not be detected at temperatures approaching the growth optimum for the strain, this study highlights the possibility that previously unsuccessful expression of pdcs in Geobacillus spp. may be the result of ineffective transcription/translation coupling.

  15. Effects of Oils Rich in Linoleic and α-Linolenic Acids on Fatty Acid Profile and Gene Expression in Goat Meat

    Directory of Open Access Journals (Sweden)

    Mahdi Ebrahimi

    2014-09-01

    Full Text Available Alteration of the lipid content and fatty acid (FA composition of foods can result in a healthier product. The aim of this study was to determine the effect of flaxseed oil or sunflower oil in the goat diet on fatty acid composition of muscle and expression of lipogenic genes in the semitendinosus (ST muscle. Twenty-one entire male Boer kid goats were fed diets containing different levels of linoleic acid (LA and α-linolenic acid (LNA for 100 days. Inclusion of flaxseed oil increased (p < 0.05 the α-linolenic acid (C18:3n-3 concentration in the ST muscle. The diet high in α-linolenic acid (p < 0.05 decreased the arachidonic acid (C20:4n-6 and conjugated linolenic acid (CLA c-9 t-11 content in the ST muscle. There was a significant (p < 0.05 upregulation of PPARα and PPARγ gene expression and downregulation of stearoyl-CoA desaturase (SCD gene in the ST muscle for the high α-linolenic acid group compared with the low α-linolenic acid group. The results of the present study show that flaxseed oil as a source of α-linolenic acid can be incorporated into the diets of goats to enrich goat meat with n-3 fatty acids, upregulate the PPARα and PPARγ, and downregulate the SCD gene expression.

  16. Identification of polymorphisms and balancing selection in the male infertility candidate gene, ornithine decarboxylase antizyme 3

    Directory of Open Access Journals (Sweden)

    Atkins John F

    2006-03-01

    Full Text Available Abstract Background The antizyme family is a group of small proteins that play a role in cell growth and division by regulating the biosynthesis of polyamines (putrescine, spermidine, spermine. Antizymes regulate polyamine levels primarily through binding ornithine decarboxylase (ODC, an enzyme key to polyamine production, and targeting ODC for destruction by the 26S proteosome. Ornithine decarboxylase antizyme 3 (OAZ3 is a testis-specific antizyme paralog and the only antizyme expressed in the mid to late stages of spermatogenesis. Methods To see if mutations in the OAZ3 gene are responsible for some cases of male infertility, we sequenced and evaluated the genomic DNA of 192 infertile men, 48 men of known paternity, and 34 African aborigines from the Mbuti tribe in the Democratic Republic of the Congo. The coding sequence of OAZ3 was further screened for polymorphisms by SSCP analysis in the infertile group and an additional 250 general population controls. Identified polymorphisms in the OAZ3 gene were further subjected to a haplotype analysis using PHASE 2.02 and Arlequin 2.0 software programs. Results A total of 23 polymorphisms were identified in the promoter, exons or intronic regions of OAZ3. The majority of these fell within a region of less than two kilobases. Two of the polymorphisms, -239 A/G in the promoter and 4280 C/T, a missense polymorphism in exon 5, may show evidence of association with male infertility. Haplotype analysis identified 15 different haplotypes, which can be separated into two divergent clusters. Conclusion Mutations in the OAZ3 gene are not a common cause of male infertility. However, the presence of the two divergent haplotypes at high frequencies in all three of our subsamples (infertile, control, African suggests that they have been maintained in the genome by balancing selection, which was supported by a test of Tajima's D statistic. Evidence for natural selection in this region implies that these haplotypes

  17. Short Chain Fatty Acids (SCFA) Reprogram Gene Expression in Human Malignant Epithelial and Lymphoid Cells

    Science.gov (United States)

    Astakhova, Lidiia; Ngara, Mtakai; Babich, Olga; Prosekov, Aleksandr; Asyakina, Lyudmila; Dyshlyuk, Lyubov; Midtvedt, Tore; Zhou, Xiaoying; Ernberg, Ingemar; Matskova, Liudmila

    2016-01-01

    The effect of short chain fatty acids (SCFAs) on gene expression in human, malignant cell lines was investigated, with a focus on signaling pathways. The commensal microbial flora produce high levels of SCFAs with established physiologic effects in humans. The most abundant SCFA metabolite in the human microflora is n-butyric acid. It is well known to activate endogenous latent Epstein-Barr virus (EBV), that was used as a reference read out system and extended to EBV+ epithelial cancer cell lines. N-butyric acid and its salt induced inflammatory and apoptotic responses in tumor cells of epithelial and lymphoid origin. Epithelial cell migration was inhibited. The n-butyric gene activation was reduced by knock-down of the cell membrane transporters MCT-1 and -4 by siRNA. N-butyric acid show biologically significant effects on several important cellular functions, also with relevance for tumor cell phenotype. PMID:27441625

  18. Inhibition of scratching behaviour caused by contact dermatitis in histidine decarboxylase gene knockout mice.

    Science.gov (United States)

    Seike, M; Ikeda, M; Kodama, H; Terui, T; Ohtsu, H

    2005-03-01

    A neuronal system dedicated to itch consists of primary afferent and spinothalamic projection neurons. Histamine is thought to be one of the main mediators for the transmission of itch sensation. However, there are little available information on the role of histamine in scratching behaviour and sensory transmission of atopic dermatitis and chronic eczema. In the present study, the role of histamine in scratching behaviour and neural conduction of sensation in the chronic eczema model was investigated by using l-histidine decarboxylase (HDC) gene knockout mice lacking histamine. The chronic contact dermatitis was induced with daily application of diphenylcyclopropenone (DCP) on a hind paw of HDC (+/+) and HDC (-/-) mice for 2 months. The observation of scratching behaviour and the hot-plate test were performed in both mice. Histological studies were performed in the skin and spinal cord tissues. Histological examination revealed that both HDC (+/+) and HDC (-/-) mice displayed the similar extent of inflammatory cell infiltration, hyperplastic epidermis and newly spreading of neuronal processes in the skin tissue. Scratching behaviour was exclusively induced in HDC (+/+) mice, whereas it was barely observed in HDC (-/-) mice. The expression of c-Fos was specifically upregulated in HDC (+/+) mice in lamina I of the spinal dorsal horn following repeated DCP application. Scratching behaviour in chronic contact dermatitis in mice was thought mainly mediated with histamine. The afferent pathway of sensation in chronic contact dermatitis model may connect with the central nervous system through lamina I of the spinal dorsal horn.

  19. Targeting ornithine decarboxylase reverses the LIN28/Let-7 axis and inhibits glycolytic metabolism in neuroblastoma.

    Science.gov (United States)

    Lozier, Ann M; Rich, Maria E; Grawe, Anissa Pedersen; Peck, Anderson S; Zhao, Ping; Chang, Anthony Ting-Tung; Bond, Jeffrey P; Sholler, Giselle Saulnier

    2015-01-01

    LIN28 has emerged as an oncogenic driver in a number of cancers, including neuroblastoma (NB). Overexpression of LIN28 correlates with poor outcome in NB, therefore drugs that impact the LIN28/Let-7 pathway could be beneficial in treating NB patients. The LIN28/Let-7 pathway affects many cellular processes including the regulation of cancer stem cells and glycolytic metabolism. Polyamines, regulated by ornithine decarboxylase (ODC) modulate eIF-5A which is a direct regulator of the LIN28/Let-7 axis. We propose that therapy inhibiting ODC will restore balance to the LIN28/Let-7 axis, suppress glycolytic metabolism, and decrease MYCN protein expression in NB. Difluoromethylornithine (DFMO) is an inhibitor of ODC in clinical trials for children with NB. In vitro experiments using NB cell lines, BE(2)-C, SMS-KCNR, and CHLA90 show that DFMO treatment reduced LIN28B and MYCN protein levels and increased Let-7 miRNA and decreased neurosphere formation. Glycolytic metabolic activity decreased with DFMO treatment in vivo. Additionally, sensitivity to DFMO treatment correlated with LIN28B overexpression (BE(2)-C>SMS-KCNR>CHLA90). This is the first study to demonstrate that DFMO treatment restores balance to the LIN28/Let-7 axis and inhibits glycolytic metabolism and neurosphere formation in NB and that PET scans may be a meaningful imaging tool to evaluate the therapeutic effects of DFMO treatment.

  20. Identification, cloning, and expression of L-amino acid oxidase from marine Pseudoalteromonas sp. B3.

    Science.gov (United States)

    Yu, Zhiliang; Zhou, Ning; Qiao, Hua; Qiu, Juanping

    2014-01-01

    L-amino acid oxidase (LAAO) is attracting more attentions due to its broad and important biological functions. Recently, an LAAO-producing marine microorganism (strain B3) was isolated from the intertidal zone of Dinghai sea area, China. Physiological, biochemical, and molecular identifications together with phylogenetic analysis congruously suggested that it belonged to the genus Pseudoalteromonas. Therefore, it was designated as Pseudoalteromonas sp. B3. Its capability of LAAO production was crossly confirmed by measuring the products of H2O2, a-keto acids, and NH4+ in oxidization reaction. Two rounds of PCR were performed to gain the entire B3-LAAO gene sequence of 1608 bps in length encoding for 535 amino acid residues. This deduced amino acid sequence showed 60 kDa of the calculated molecular mass, supporting the SDS-PAGE result. Like most of flavoproteins, B3-LAAO also contained two conserved typical motifs, GG-motif and βαβ-dinucleotide-binding domain motif. On the other hand, its unique substrate spectra and sequence information suggested that B3-LAAO was a novel LAAO. Our results revealed that it could be functionally expressed in E. coli BL21(DE3) using vectors, pET28b(+) and pET20b(+). However, compared with the native LAAO, the expression level of the recombinant one was relatively low, most probably due to the formation of inclusion bodies. Several solutions are currently being conducted in our lab to increase its expression level.

  1. Glutamic acid promotes monacolin K production and monacolin K biosynthetic gene cluster expression in Monascus.

    Science.gov (United States)

    Zhang, Chan; Liang, Jian; Yang, Le; Chai, Shiyuan; Zhang, Chenxi; Sun, Baoguo; Wang, Chengtao

    2017-12-01

    This study investigated the effects of glutamic acid on production of monacolin K and expression of the monacolin K biosynthetic gene cluster. When Monascus M1 was grown in glutamic medium instead of in the original medium, monacolin K production increased from 48.4 to 215.4 mg l(-1), monacolin K production increased by 3.5 times. Glutamic acid enhanced monacolin K production by upregulating the expression of mokB-mokI; on day 8, the expression level of mokA tended to decrease by Reverse Transcription-polymerase Chain Reaction. Our findings demonstrated that mokA was not a key gene responsible for the quantity of monacolin K production in the presence of glutamic acid. Observation of Monascus mycelium morphology using Scanning Electron Microscope showed glutamic acid significantly increased the content of Monascus mycelium, altered the permeability of Monascus mycelium, enhanced secretion of monacolin K from the cell, and reduced the monacolin K content in Monascus mycelium, thereby enhancing monacolin K production.

  2. Nucleic acid modulation of gene expression: approaches for nucleic acid therapeutics against cancer.

    Science.gov (United States)

    Nakata, Yuji; Kim, Tae-Kon; Shetzline, Susan; Gewirtz, Alan M

    2005-01-01

    Most cancers are characterized by abnormal gene expression, which is thought to contribute to the pathogenesis and maintenance of the malignant phenotype; abnormal proliferation, maturation, and apoptosis. Silencing such genes would appear to be a rational approach to the therapy of cancer, and some preliminary clinical studies support this concept. Of the strategies available, the anti-mRNA gene silencing approach has attracted much attention and is the focus of this review. This strategy includes three types of agents: (1) single-stranded antisense oligonucleotides; (2) catalytically active oligonucleotides, such as ribozymes, and DNAzymes that possess inherent RNA cleaving activity; and (3) small interfering RNA (siRNA) molecules that induce RNA interference (RNAi). Among these agents, antisense oligonucleotides, especially phosphorothioate (PS) oligonucleotides, have been the most frequently used in clinical trials. In this article, we provide an overview of anti-mRNA gene silencing agents and their development for use as cancer therapeutics.

  3. Identification and heterologous expression of a Δ4-fatty acid desaturase gene from Isochrysis sphaerica.

    Science.gov (United States)

    Guo, Bing; Jiang, Mulan; Wan, Xia; Gong, Yangmin; Liang, Zhuo; Hu, Chuanjiong

    2013-10-28

    The marine microalga Isochrysis sphaerica is rich in the very-long-chain polyunsaturated fatty acids, including eicosapentaenoic acid (EPA, C20:5ω-3) and docosahexaenoic acid (DHA, C22:6ω-3) that are important to human health. Here, we report a functional characterization of a Δ4-fatty acid desaturase gene (FAD4) from I. sphaerica. IsFAD4 contains a 1,284 bp open reading frame encoding a 427 amino acid polypeptide. The deduced amino sequence comprises three conserved histidine motifs and a cytochrome b5 domain at its N-terminus. Phylogenetic analysis indicated that IsFad4 formed a unique Isochrysis clade distinct from the counterparts of other eukaryotes. Heterologous expression of IsFAD4 in Pichia pastoris showed that IsFad4 was able to desaturate docosapentaenoic acid (DPA) to form DHA, and the rate of converting DPA to DHA was 79.8%. These results throw light on the potential industrial production of specific polyunsaturated fatty acids through IsFAD4 transgenic yeast or oil crops.

  4. Modulation of antimicrobial host defense peptide gene expression by free fatty acids.

    Directory of Open Access Journals (Sweden)

    Lakshmi T Sunkara

    Full Text Available Routine use of antibiotics at subtherapeutic levels in animal feed drives the emergence of antimicrobial resistance. Development of antibiotic-alternative approaches to disease control and prevention for food animals is imperatively needed. Previously, we showed that butyrate, a major species of short-chain fatty acids (SCFAs fermented from undigested fiber by intestinal microflora, is a potent inducer of endogenous antimicrobial host defense peptide (HDP genes in the chicken (PLoS One 2011, 6: e27225. In the present study, we further revealed that, in chicken HD11 macrophages and primary monocytes, induction of HDPs is largely in an inverse correlation with the aliphatic hydrocarbon chain length of free fatty acids, with SCFAs being the most potent, medium-chain fatty acids moderate and long-chain fatty acids marginal. Additionally, three SCFAs, namely acetate, propionate, and butyrate, exerted a strong synergy in augmenting HDP gene expression in chicken cells. Consistently, supplementation of chickens with a combination of three SCFAs in water resulted in a further reduction of Salmonella enteritidis in the cecum as compared to feeding of individual SCFAs. More importantly, free fatty acids enhanced HDP gene expression without triggering proinflammatory interleukin-1β production. Taken together, oral supplementation of SCFAs is capable of boosting host immunity and disease resistance, with potential for infectious disease control and prevention in animal agriculture without relying on antibiotics.

  5. Bile acid-induced virulence gene expression of Vibrio parahaemolyticus reveals a novel therapeutic potential for bile acid sequestrants.

    Directory of Open Access Journals (Sweden)

    Kazuyoshi Gotoh

    Full Text Available Vibrio parahaemolyticus, a bacterial pathogen, causes human gastroenteritis. A type III secretion system (T3SS2 encoded in pathogenicity island (Vp-PAI is the main contributor to enterotoxicity and expression of Vp-PAI encoded genes is regulated by two transcriptional regulators, VtrA and VtrB. However, a host-derived inducer for the Vp-PAI genes has not been identified. Here, we demonstrate that bile induces production of T3SS2-related proteins under osmotic conditions equivalent to those in the intestinal lumen. We also show that bile induces vtrA-mediated vtrB transcription. Transcriptome analysis of bile-responsive genes revealed that bile strongly induces expression of Vp-PAI genes in a vtrA-dependent manner. The inducing activity of bile was diminished by treatment with bile acid sequestrant cholestyramine. Finally, we demonstrate an in vivo protective effect of cholestyramine on enterotoxicity and show that similar protection is observed in infection with a different type of V. parahaemolyticus or with non-O1/non-O139 V. cholerae strains of vibrios carrying the same kind of T3SS. In summary, these results provide an insight into how bacteria, through the ingenious action of Vp-PAI genes, can take advantage of an otherwise hostile host environment. The results also reveal a new therapeutic potential for widely used bile acid sequestrants in enteric bacterial infections.

  6. Poultry fat decreased fatty acid transporter protein mRNA expression and affected fatty acid composition in chickens

    Directory of Open Access Journals (Sweden)

    Yuan Jianmin

    2012-05-01

    Full Text Available Abstract Background A study was undertaken to examine the effects of poultry fat (PF compared with those of soybean oil (SBO on intestinal development, fatty acid transporter protein (FATP mRNA expression, and fatty acid composition in broiler chickens. A total of 144 day-old male commercial broilers were randomly allocated to 2 treatment groups (6 replicates of 12 chicks for each treatment and fed isocaloric diets containing 3.0% PF or 2.7% SBO at 0 to 3 wk and 3.8% PF or 3.5% SBO at 4 to 6 wk, respectively. Results PF had no influence on intestinal morphology, weight, or DNA, RNA, or protein concentrations at 2, 4, and 6 wk of age. However, compared with SBO, PF significantly decreased FATP mRNA abundance at 4 wk (P = 0.009 and 6 wk of age (P P = 0.039; and decreased C18:2 (P = 0.015, C18:3 (P P = 0.018, Σ-polyunsaturated fatty acids (Σ-PUFA (P = 0.020, and the proportion of PUFA (P P = 0.010, C18:3 (P P P = 0.005, and the proportion of PUFA (P  Conclusions PF decreases FATP and L-FABP mRNA expression and decreased the proportion of PUFA in the intestinal mucosa and breast muscle.

  7. Oxidative decarboxylation of mandelic acid derivative by recombinant Escherichia coli: a novel method of ethyl vanillin synthesis.

    Science.gov (United States)

    Pan, Xiao-Xia; Li, Jing-Jing; Wang, Mei-Gui; He, Wen-Sen; Jia, Cheng-Sheng; Zhang, Xiao-Ming; Feng, Biao; Li, Da-Li; Zeng, Zeng

    2013-06-01

    The benzoylformate decarboxylase gene (mdlC) from Pseudomonas putida was expressed in Escherichia coli BL21(DE3). The recombinant strain together with E. coli/pET30a-mdlB converted (S)-3-ethoxy-4-hydroxymandelic acid (S-EMA) into ethyl vanillin without ethyl vanillin degradation. 4 g ethyl vanillin/l was obtained from 10 g EMA/l within 12 h at 30 °C. This is the first report on the biotransformation of (S)-EMA to ethyl vanillin.

  8. Expression of PPARα modifies fatty acid effects on insulin secretion in uncoupling protein-2 knockout mice

    Directory of Open Access Journals (Sweden)

    Chan Catherine B

    2007-03-01

    Full Text Available Abstract Aims/hypothesis In uncoupling protein-2 (UCP2 knockout (KO mice, protection of beta cells from fatty acid exposure is dependent upon transcriptional events mediated by peroxisome proliferator-activated receptor-α (PPARα. Methods PPARα expression was reduced in isolated islets from UCP2KO and wild-type (WT mice with siRNA for PPARα (siPPARα overnight. Some islets were also cultured with oleic or palmitic acid, then glucose stimulated insulin secretion (GSIS was measured. Expression of genes was examined by quantitative RT-PCR or immunoblotting. PPARα activation was assessed by oligonucleotide consensus sequence binding. Results siPPARα treatment reduced PPARα protein expression in KO and WT islets by >85%. In siPPARα-treated UCP2KO islets, PA but not OA treatment significantly decreased the insulin response to 16.5 mM glucose. In WT islets, siPPARα treatment did not modify GSIS in PA and OA exposed groups. In WT islets, PA treatment significantly increased UCP2 mRNA and protein expression. Both PA and OA treatment significantly increased PPARα expression in UCP2KO and WT islets but OA treatment augmented PPARα protein expression only in UCP2KO islets (p Conclusion These data show that the negative effect of saturated fatty acid on GSIS is mediated by PPARα/UCP2. Knockout of UCP2 protects beta-cells from PA exposure. However, in the absence of both UCP2 and PPARα even a short exposure (24 h to PA significantly impairs GSIS.

  9. Expression Pattern of Fatty Acid Binding Proteins in Celiac Disease Enteropathy

    Directory of Open Access Journals (Sweden)

    Natalia M. Bottasso Arias

    2015-01-01

    Full Text Available Celiac disease (CD is an immune-mediated enteropathy that develops in genetically susceptible individuals following exposure to dietary gluten. Severe changes at the intestinal mucosa observed in untreated CD patients are linked to changes in the level and in the pattern of expression of different genes. Fully differentiated epithelial cells express two isoforms of fatty acid binding proteins (FABPs: intestinal and liver, IFABP and LFABP, respectively. These proteins bind and transport long chain fatty acids and also have other important biological roles in signaling pathways, particularly those related to PPARγ and inflammatory processes. Herein, we analyze the serum levels of IFABP and characterize the expression of both FABPs at protein and mRNA level in small intestinal mucosa in severe enteropathy and normal tissue. As a result, we observed higher levels of circulating IFABP in untreated CD patients compared with controls and patients on gluten-free diet. In duodenal mucosa a differential FABPs expression pattern was observed with a reduction in mRNA levels compared to controls explained by the epithelium loss in severe enteropathy. In conclusion, we report changes in FABPs’ expression pattern in severe enteropathy. Consequently, there might be alterations in lipid metabolism and the inflammatory process in the small intestinal mucosa.

  10. ASIC3, an acid-sensing ion channel, is expressed in metaboreceptive sensory neurons

    Directory of Open Access Journals (Sweden)

    Fierro Leonardo

    2005-11-01

    Full Text Available Abstract Background ASIC3, the most sensitive of the acid-sensing ion channels, depolarizes certain rat sensory neurons when lactic acid appears in the extracellular medium. Two functions have been proposed for it: 1 ASIC3 might trigger ischemic pain in heart and muscle; 2 it might contribute to some forms of touch mechanosensation. Here, we used immunocytochemistry, retrograde labelling, and electrophysiology to ask whether the distribution of ASIC3 in rat sensory neurons is consistent with either of these hypotheses. Results Less than half (40% of dorsal root ganglion sensory neurons react with anti-ASIC3, and the population is heterogeneous. They vary widely in cell diameter and express different growth factor receptors: 68% express TrkA, the receptor for nerve growth factor, and 25% express TrkC, the NT3 growth factor receptor. Consistent with a role in muscle nociception, small ( Conclusion Our data indicates that: 1 ASIC3 is expressed in a restricted population of nociceptors and probably in some non-nociceptors; 2 co-expression of ASIC3 and CGRP, and the absence of P2X3, are distinguishing properties of a class of sensory neurons, some of which innervate blood vessels. We suggest that these latter afferents may be muscle metaboreceptors, neurons that sense the metabolic state of muscle and can trigger pain when there is insufficient oxygen.

  11. Expression of rapeseed microsomal lysophosphatidic acid acyltransferase isozymes enhances seed oil content in Arabidopsis.

    Science.gov (United States)

    Maisonneuve, Sylvie; Bessoule, Jean-Jacques; Lessire, René; Delseny, Michel; Roscoe, Thomas J

    2010-02-01

    In higher plants, lysophosphatidic acid acyltransferase (LPAAT), located in the cytoplasmic endomembrane compartment, plays an essential role in the synthesis of phosphatidic acid, a key intermediate in the biosynthesis of membrane phospholipids in all tissues and storage lipids in developing seeds. In order to assess the contribution of LPAATs to the synthesis of storage lipids, we have characterized two microsomal LPAAT isozymes, the products of homoeologous genes that are expressed in rapeseed (Brassica napus). DNA sequence homologies, complementation of a bacterial LPAAT-deficient mutant, and enzymatic properties confirmed that each of two cDNAs isolated from a Brassica napus immature embryo library encoded a functional LPAAT possessing the properties of a eukaryotic pathway enzyme. Analyses in planta revealed differences in the expression of the two genes, one of which was detected in all rapeseed tissues and during silique and seed development, whereas the expression of the second gene was restricted predominantly to siliques and developing seeds. Expression of each rapeseed LPAAT isozyme in Arabidopsis (Arabidopsis thaliana) resulted in the production of seeds characterized by a greater lipid content and seed mass. These results support the hypothesis that increasing the expression of glycerolipid acyltransferases in seeds leads to a greater flux of intermediates through the Kennedy pathway and results in enhanced triacylglycerol accumulation.

  12. Folic acid protects against arsenic-mediated embryo toxicity by up-regulating the expression of Dvr1.

    Science.gov (United States)

    Ma, Yan; Zhang, Chen; Gao, Xiao-Bo; Luo, Hai-Yan; Chen, Yang; Li, Hui-hua; Ma, Xu; Lu, Cai-Ling

    2015-11-05

    As a nutritional factor, folic acid can prevent cardiac and neural defects during embryo development. Our previous study showed that arsenic impairs embryo development by down-regulating Dvr1/GDF1 expression in zebrafish. Here, we investigated whether folic acid could protect against arsenic-mediated embryo toxicity. We found that folic acid supplementation increases hatching and survival rates, decreases malformation rate and ameliorates abnormal cardiac and neural development of zebrafish embryos exposed to arsenite. Both real-time PCR analysis and whole in-mount hybridization showed that folic acid significantly rescued the decrease in Dvr1 expression caused by arsenite. Subsequently, our data demonstrated that arsenite significantly decreased cell viability and GDF1 mRNA and protein levels in HEK293ET cells, while folic acid reversed these effects. Folic acid attenuated the increase in subcellular reactive oxygen species (ROS) levels and oxidative adaptor p66Shc protein expression in parallel with the changes in GDF1 expression and cell viability. P66Shc knockdown significantly inhibited the production of ROS and the down-regulation of GDF1 induced by arsenite. Our data demonstrated that folic acid supplementation protected against arsenic-mediated embryo toxicity by up-regulating the expression of Dvr1/GDF1, and folic acid enhanced the expression of GDF1 by decreasing p66Shc expression and subcellular ROS levels.

  13. Effect of retinoic acid on expression of LINGO-1 and neural regeneration after cerebral ischemia.

    Science.gov (United States)

    Xing, Hong-yi; Meng, Er-yan; Xia, Yuan-peng; Peng, Hai

    2015-02-01

    The purpose of this study was to observe the expression of LINGO-1 after cerebral ischemia, investigate the effects of retinoic acid (RA) on the expression of LINGO-1 and GAP-43, and the number of synapses, and to emplore the repressive effect of LINGO-1 on neural regeneration after cerebral ischemia. The model of permanent focal cerebral ischemia was established by the modified suture method of middle cerebral artery occlusion (MCAO) in Sprague-Dawley (SD) rats. The expression of LINGO-1 was detected by Western blotting and that of GAP-43 by immunohistochemistry. The number of synapses was observed by transmission electron microscopy. The SD rats were divided into three groups: sham operation (sham) group, cerebral ischemia (CI) group and RA treatment (RA) group. The results showed that the expression level of LINGO-1 at 7th day after MCAO in sham, CI and RA groups was 0.266 ± 0.019, 1.215 ± 0.063 and 0.702 ± 0.081, respectively (PLINGO-1 expression is up-regulated after cerebral ischemia, and RA inhibits the expression of LINGO-1, promotes the expression of GAP-43 and increases the number of synapses. It suggests that LINGO-1 may be involved in the pathogenesis of cerebral ischemia, which may provide an experimenal basis for LINGO-1 antogonist, RA, for the treatment of cerebral ischemia.

  14. Dietary Berries and Ellagic Acid Prevent Oxidative DNA Damage and Modulate Expression of DNA Repair Genes

    Directory of Open Access Journals (Sweden)

    Ramesh C. Gupta

    2008-03-01

    Full Text Available DNA damage is a pre-requisite for the initiation of cancer and agents that reduce this damage are useful in cancer prevention. In this study, we evaluated the ability of whole berries and berry phytochemical, ellagic acid to reduce endogenous oxidative DNA damage. Ellagic acid was selected based on > 95% inhibition of 8-oxodeoxyguosine (8-oxodG and other unidentified oxidative DNA adducts induced by 4-hydroxy-17B;-estradiol and CuCl2 in vitro. Inhibition of the latter occurred at lower concentrations (10 u(microM than that for 8-oxodG (100 u(microM. In the in vivo study, female CD-1 mice (n=6 were fed either a control diet or diet supplemented with ellagic acid (400 ppm and dehydrated berries (5% w/w with varying ellagic acid contents -- blueberry (low, strawberry (medium and red raspberry (high, for 3 weeks. Blueberry and strawberry diets showed moderate reductions in endogenous DNA adducts (25%. However, both red raspberry and ellagic acid diets showed a significant reduction of 59% (p < 0.001 and 48% (p < 0.01, respectively. Both diets also resulted in a 3-8 fold over-expression of genes involved in DNA repair such as xeroderma pigmentosum group A complementing protein (XPA, DNA excision repair protein (ERCC5 and DNA ligase III (DNL3. These results suggest that red raspberry and ellagic acid reduce endogenous oxidative DNA damage by mechanisms which may involve increase in DNA repair.

  15. Characterization and translational regulation of the arginine decarboxylase gene in carnation (Dianthus caryophyllus L.).

    Science.gov (United States)

    Chang, K S; Lee, S H; Hwang, S B; Park, K Y

    2000-10-01

    Arginine decarboxylase (ADC; EC 4.1.1.9) is a key enzyme in polyamine biosynthesis in plants. We characterized a carnation genomic clone, gDcADC8, in which the deduced polypeptide of ADC was 725 amino acids with a molecular mass of 77.7 kDa. The unusually long 5'-UTR that contained a short upstream open reading frame (uORF) of seven amino acids (MQKSLHI) was predicted to form an extensive secondary structure (free energy of approximately -117 kcal mol-1) using the Zuker m-fold algorithm. The result that an ADC antibody detected two bands of 45 and 33 kDa in a petal extract suggested the full length of the 78 kDa polypeptide precursor converted into two polypeptides in the processing reaction. To investigate the role of the transcript leader in translation, in vitro transcription/translation reactions with various constructs of deletion and mutation were performed using wheat germ extract. The ADC transcript leader affected positively downstream translation in both wheatgerm extract and primary transformant overexpressing ADC gene. It was demonstrated that heptapeptide (8.6 kDa) encoded by the ADC uORF was synthesized in vitro. Both uORF peptide, and the synthetic heptapeptide MQKSLHI of the uORF, repressed the translation of downstream ORF. Mutation of the uORF ATG codon alleviated the inhibitory effect. ORF translation was not affected by either a frame-shift mutation in uORF or a random peptide. To our knowledge, this is the first report to provide evidence that a uORF may inhibit the translation of a downstream ORF, not only in cis but also in trans, and that the leader sequence of the ADC gene is important for efficient translation.

  16. Effects of Salvianolic Acid B on Protein Expression in Human Umbilical Vein Endothelial Cells

    OpenAIRE

    Tsong-Min Chang; Guey-Yueh Shi; Hua-Lin Wu; Chieh-Hsi Wu; Yan-Di Su; Hui-Lin Wang; Hsin-Yun Wen; Huey-Chun Huang

    2011-01-01

    Salvianolic acid B (Sal B), a pure water-soluble compound extracted from Radix Salviae miltiorrhizae, has been reported to possess potential cardioprotective efficacy. To identify proteins or pathways by which Sal B might exert its protective activities on the cardiovascular system, two-dimensional gel electrophoresis-based comparative proteomics was performed, and proteins altered in their expression level after Sal B treatment were identified by MALDI-TOF MS/MS. Human umbilical vein endothe...

  17. Calcium affecting protein expression in longan under simulated acid rain stress.

    Science.gov (United States)

    Pan, Tengfei; Li, Yongyu; Ma, Cuilan; Qiu, Dongliang

    2015-08-01

    Longan (Dimocarpus longana Lour. cv. Wulongling) of uniform one-aged seedlings grown in pots were selected to study specific proteins expressed in leaves under simulated acid rain (SiAR) stress and exogenous Ca(2+) regulation. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) results showed that there was a protein band specifically expressed under SiAR of pH 2.5 stress for 15 days with its molecular weight of about 23 kD. A 17 kD protein band specifically expressed after SiAR stress 5 days. Compared with pH 2.5, the pH 3.5 of SiAR made a less influence to protein expression. Two-dimensional electrophoresis (2-DE) results showed that six new specific proteins including C4 (20.2 kD pI 6.0), F (24 kD pI 6.35), B3 (22.3 kD pI 6.35), B4 (23.5 kD pI 6.5), C5 (21.8 kD pI 5.6), and C6 (20.2 kD pI 5.6) specifically expressed. C4 always expressed during SiAR stress. F expressed under the stress of pH 2.5 for 15 days and expressed in all pH SiAR stress for 20 days. The expression of proteins including B3, C5, and C6 was related to pH value and stress intensity of SiAR. The expression of B4 resulted from synergistic effects of SiAR and Ca. The expression of G1 (Mr 19.3 kD, pI 4.5), G2 (Mr 17.8 kD, pI 4.65), G3 (Mr 16.6 kD, pI 4.6), and G4 (Mr 14.7 kD, pI 4.4) enhanced under the treatment of 5 mM ethylene glycol tetraacetic acid (EGTA) and 2 mM chlorpromazine (CPZ). These proteins showed antagonistic effects and might be relative to the Ca-calmodulin (Ca-CaM) system of longan in response to SiAR stress.

  18. Genomewide expression analysis in amino acid-producing bacteria using DNA microarrays.

    Science.gov (United States)

    Polen, Tino; Wendisch, Volker F

    2004-01-01

    DNA microarray technology has become an important research tool for biotechnology and microbiology. It is now possible to characterize genetic diversity and gene expression in a genomewide manner. DNA microarrays have been applied extensively to study the biology of many bacteria including Escherichia coli, but only recently have they been developed for the Gram-positive Corynebacterium glutamicum. Both bacteria are widely used for biotechnological amino acid production. In this article, in addition to the design and generation of microarrays as well as their use in hybridization experiments and subsequent data analysis, we describe recent applications of DNA microarray technology regarding amino acid production in C. glutamicum and E. coli. We also discuss the impact of functional genomics studies on fundamental as well as applied aspects of amino acid production with C. glutamicum and E. coli.

  19. Expression of D-myo-inositol-3-phosphate synthase in soybean. Implications for phytic acid biosynthesis.

    Science.gov (United States)

    Hegeman, C E; Good, L L; Grabau, E A

    2001-04-01

    Phytic acid, a phosphorylated derivative of myo-inositol, functions as the major storage form of phosphorus in plant seeds. Myo-inositol phosphates, including phytic acid, play diverse roles in plants as signal transduction molecules, osmoprotectants, and cell wall constituents. D-myo-inositol-3-phosphate synthase (MIPS EC 5.5.1.4) catalyzes the first step in de novo synthesis of myo-inositol. A soybean (Glycine max) MIPS cDNA (GmMIPS1) was isolated by reverse transcriptase-PCR using consensus primers designed from highly conserved regions in other plant MIPS sequences. Southern-blot analysis and database searches indicated the presence of at least four MIPS genes in the soybean genome. Northern-blot and immunoblot analyses indicated higher MIPS expression and accumulation in immature seeds than in other soybean tissues. MIPS was expressed early in the cotyledonary stage of seed development. The GmMIPS1 expression pattern suggested that it encodes a MIPS isoform that functions in seeds to generate D-myo-inositol-3-phosphate as a substrate for phytic acid biosynthesis.

  20. Profiling of hepatic gene expression in rats treated with fibric acid analogs

    Energy Technology Data Exchange (ETDEWEB)

    Cornwell, Paul D.; Souza, Angus T. de; Ulrich, Roger G

    2004-05-18

    Peroxisome proliferator-activated receptors (PPARs) are a group of nuclear receptors whose ligands include fatty acids, eicosanoids and the fibrate class of drugs. In humans, fibrates are used to treat dyslipidemias. In rodents, fibrates cause peroxisome proliferation, a change that might explain the observed hepatomegaly. In this study, rats were treated with multiple dose levels of six fibric acid analogs (including fenofibrate) for up to two weeks. Pathological analysis identified hepatocellular hypertrophy as the only sign of hepatotoxicity, and only one compound at the highest dose caused any significant increase in serum ALT or AST activity. RNA profiling revealed that the expression of 1288 genes was related to dose or length of treatment and correlated with hepatocellular hypertrophy. This gene list included expression changes that were consistent with increased mitochondrial and peroxisomal {beta}-oxidation, increased fatty acid transport, increased hepatic uptake of LDL-cholesterol, decreased hepatic uptake of glucose, decreased gluconeogenesis and decreased glycolysis. These changes are likely linked to many of the clinical benefits of fibrate drugs, including decreased serum triglycerides, decreased serum LDL-cholesterol and increased serum HDL-cholesterol. In light of the fact that all six compounds stimulated similar or identical changes in the expression of this set of 1288 genes, these results indicate that hepatomegaly is due to PPAR{alpha} activation, although signaling through other receptors (e.g. PPAR{gamma}, RXR) or through non-receptor pathways cannot be excluded.

  1. Gene expression in retinoic acid-induced neural tube defects A cDNA mieroarray analysis

    Institute of Scientific and Technical Information of China (English)

    Xiaodong Long; Zhong Yang; Yi Zeng; Hongli Li; Yangyun Han; Chao You

    2009-01-01

    BACKGROUND: Neural tube defects can be induced by abnormal factors in vivo or in vitro during development. However, the molecular mechanisms of neural tube defect induction, and the related gene expression and regulation are still unknown.OBJECTIVE: To compare the differences in gene expression between normal embryos and those with neural tube defects.DESIGN, TIME AND SETTING: A neural development study was performed at the Department of Neurobiology, Third Military Medical University of Chinese PLA between January 2006 and October 2007.MATERIALS: Among 120 adult Kunming mice, 60 pregnant mice were randomly and evenly divided into a retinoic acid group (n = 30) and a normal control group (n =30). The retinoic acid was produced by Sigma, USA, the gene microarray by the Amersham Pharmacia Company, Hong Kong, and the gene sequence was provided by the Incyte database, USA.METHODS: Retinoic acid was administered to prepare models of neural tube defects, and corn oil was similady administered to the normal control group. Total RNA was extracted from embryonic tissue of the two groups using a Trizol kit, and a cDNA microarray containing 1 100 known genes was used to compare differences in gene expression between the normal control group and the retinoic acid group on embryonic (E) clay 10.5 and 11.5. Several differentially expressed genes were randomly selected from the two groups for Northern blotting, to verify the results of the cDNA microarray.MAIN OUTCOME MEASURES: Morphological changes and differential gene expression between the normal control group and the retinoic acid group.RESULTS: Anatomical microscopy demonstrated that an intact closure of the brain was formed in the normal mouse embryos by days E10.5 and E11.5. The cerebral appearance was full and smooth, and the surface of the spine was intact. However, in the retinoic acid group on days E10.5 and E11.5, there were more dead embryos. Morphological malformations typically included non-closure at the top of

  2. Quantitative analysis of histidine decarboxylase gene (hdcA) transcription and histamine production by Streptococcus thermophilus PRI60 under conditions relevant to cheese making.

    Science.gov (United States)

    Rossi, Franca; Gardini, Fausto; Rizzotti, Lucia; La Gioia, Federica; Tabanelli, Giulia; Torriani, Sandra

    2011-04-01

    This study evaluated the influence of parameters relevant for cheese making on histamine formation by Streptococcus thermophilus. Strains possessing a histidine decarboxylase (hdcA) gene represented 6% of the dairy isolates screened. The most histaminogenic, S. thermophilus PRI60, exhibited in skim milk a high basal level of expression of hdcA, upregulation in the presence of free histidine and salt, and repression after thermization. HdcA activity persisted in cell extracts, indicating that histamine might accumulate after cell lysis in cheese.

  3. Quantitative Analysis of Histidine Decarboxylase Gene (hdcA) Transcription and Histamine Production by Streptococcus thermophilus PRI60 under Conditions Relevant to Cheese Making▿†

    Science.gov (United States)

    Rossi, Franca; Gardini, Fausto; Rizzotti, Lucia; La Gioia, Federica; Tabanelli, Giulia; Torriani, Sandra

    2011-01-01

    This study evaluated the influence of parameters relevant for cheese making on histamine formation by Streptococcus thermophilus. Strains possessing a histidine decarboxylase (hdcA) gene represented 6% of the dairy isolates screened. The most histaminogenic, S. thermophilus PRI60, exhibited in skim milk a high basal level of expression of hdcA, upregulation in the presence of free histidine and salt, and repression after thermization. HdcA activity persisted in cell extracts, indicating that histamine might accumulate after cell lysis in cheese. PMID:21378060

  4. A tyrosine decarboxylase catalyzes the initial reaction of the salidroside biosynthesis pathway in Rhodiola sachalinensis.

    Science.gov (United States)

    Zhang, Ji-Xing; Ma, Lan-Qing; Yu, Han-Song; Zhang, Hong; Wang, Hao-Tian; Qin, Yun-Fei; Shi, Guang-Lu; Wang, You-Nian

    2011-08-01

    Salidroside, the 8-O-β-D-glucoside of tyrosol, is the main bioactive component of Rhodiola species and is found mainly in the plant roots. It is well known that glucosylation of tyrosol is the final step in the biosynthesis of salidroside; however, the biosynthetic pathway of tyrosol and its regulation are less well understood. A summary of the results of related studies revealed that the precursor of tyrosol might be tyramine, which is synthesized from tyrosine. In this study, a cDNA clone encoding tyrosine decarboxylase (TyrDC) was isolated from Rhodiola sachalinensis A. Bor using rapid amplification of cDNA ends. The resulting cDNA was designated RsTyrDC. RNA gel-blot analysis revealed that the predominant sites of expression in plants are the roots and high levels of transcripts are also found in callus tissue culture. Functional analysis revealed that tyrosine was best substrate of recombinant RsTyrDC. The over-expression of the sense-RsTyrDC resulted in a marked increase of tyrosol and salidroside content, but the levels of tyrosol and salidroside were 274 and 412%, respectively, lower in the antisense-RsTyrDC transformed lines than those in the controls. The data presented here provide in vitro and in vivo evidence that the RsTyrDC can regulate the tyrosol and salidroside biosynthesis, and the RsTyrDC is most likely to have an important function in the initial reaction of the salidroside biosynthesis pathway in R. sachalinensis.

  5. Sesamin modulates gene expression without corresponding effects on fatty acids in Atlantic salmon (Salmo salar L.).

    Science.gov (United States)

    Schiller Vestergren, A; Wagner, L; Pickova, J; Rosenlund, G; Kamal-Eldin, A; Trattner, S

    2012-09-01

    This study examined the effects of sesamin inclusion in vegetable oil-based diets fed to Atlantic salmon (Salmo salar L.). The diets used differed in n-6/n-3 fatty acid (FA) ratio (0.5 and 1) and sesamin content (high 5.8 g/kg, low 1.16 g/kg and no sesamin). The oils used in the feeds were a mixture of rapeseed, linseed and palm oil. Fish were fed for 4 months. Fatty acids and expression of hepatic genes involved in transcription, lipid uptake, desaturation, elongation and β-oxidation were measured. No major effects on the percentage of DHA in white muscle, liver triacylglycerol and phospholipid fraction were detected. Genes involved in β-oxidation, elongation and desaturation were affected by sesamin addition. Limited effects were seen on any of the transcription factors tested and no effect was seen on the expression of peroxisome proliferator-activated receptors (PPAR). Expression of both SREBP-1 and SREBP-2 increased with sesamin addition. It was concluded that supplementation of fish feed with a high level of sesamin had a negative effect on the growth rate and live weight and did not alter the proportions of DHA in tissues even though gene expression was affected. Thus, more studies are needed to formulate a diet that would increase the percentage of DHA in fish without negative effects on fish growth.

  6. Structural and degradative aspects of ornithine decarboxylase antizyme inhibitor 2

    Directory of Open Access Journals (Sweden)

    Bruno Ramos-Molina

    2014-01-01

    Full Text Available Ornithine decarboxylase (ODC is the key enzyme in the polyamine biosynthetic pathway. ODC levels are controlled by polyamines through the induction of antizymes (AZs, small proteins that inhibit ODC and target it to proteasomal degradation without ubiquitination. Antizyme inhibitors (AZIN1 and AZIN2 are proteins homologous to ODC that bind to AZs and counteract their negative effect on ODC. Whereas ODC and AZIN1 are well-characterized proteins, little is known on the structure and stability of AZIN2, the lastly discovered member of this regulatory circuit. In this work we first analyzed structural aspects of AZIN2 by combining biochemical and computational approaches. We demonstrated that AZIN2, in contrast to ODC, does not form homodimers, although the predicted tertiary structure of the AZIN2 monomer was similar to that of ODC. Furthermore, we identified conserved residues in the antizyme-binding element, whose substitution drastically affected the capacity of AZIN2 to bind AZ1. On the other hand, we also found that AZIN2 is much more labile than ODC, but it is highly stabilized by its binding to AZs. Interestingly, the administration of the proteasome inhibitor MG132 caused differential effects on the three AZ-binding proteins, having no effect on ODC, preventing the degradation of AZIN1, but unexpectedly increasing the degradation of AZIN2. Inhibitors of the lysosomal function partially prevented the effect of MG132 on AZIN2. These results suggest that the degradation of AZIN2 could be also mediated by an alternative route to that of proteasome. These findings provide new relevant information on this unique regulatory mechanism of polyamine metabolism.

  7. Catalysis of acetoin formation by brewers' yeast pyruvate decarboxylase isozymes.

    Science.gov (United States)

    Stivers, J T; Washabaugh, M W

    1993-12-14

    Catalysis of C(alpha)-proton transfer from 2-(1-hydroxyethyl)thiamin diphosphate (HETDP) by pyruvate decarboxylase isozymes (PDC; EC 4.1.1.1) from Saccharomyces carlsbergensis was investigated by determining the steady-state kinetics of the reaction of [1-L]acetaldehyde (L = H, D, or T) to form acetoin and the primary kinetic isotope effects on the reaction. The PDC isozyme mixture and alpha 4 isozyme (alpha 4-PDC) have different steady-state kinetic parameters and isotope effects for acetoin formation in the presence and absence of the nonsubstrate allosteric effector pyruvamide: pyruvamide activation occurs by stabilization of the acetaldehyde/PDC ternary complex. The magnitudes of primary L(V/K)-type (L = D or T) isotope effects on C(alpha)-proton transfer from alpha 4-PDC-bound HETDP provide no evidence for significant breakdown of the Swain-Schaad relationship that would indicate partitioning of the putative C(alpha)-carbanion/enamine intermediate between HETDP and products. The substrate concentration dependence of the deuterium primary kinetic isotope effects provides evidence for an intrinsic isotope effect of 4.1 for C(alpha)-proton transfer from alpha 4-PDC-bound HETDP. A 1.10 +/- 0.02-fold 14C isotope discrimination against [1,2-14C]acetaldehyde in acetoin formation is inconsistent with a stepwise mechanism, in which the addition step occurs after rate-limiting formation of the C(alpha)-carbanion/enamine as a discrete enzyme-bound intermediate, and provides evidence for a concerted reaction mechanism with an important component of carbon-carbon bond formation in the transition state.

  8. The molecular mechanism of leptin secretion and expression induced by aristolochic acid in kidney fibroblast.

    Directory of Open Access Journals (Sweden)

    Tsung-Chieh Lin

    Full Text Available BACKGROUND: Leptin is a peptide hormone playing pivotal role in regulating food intake and energy expenditure. Growing evidence has suggested the pro-inflammatory and fibrogenic properties of leptin. In addition, patients with renal fibrosis have higher level of plasma leptin, which was due to the increased leptin production. Aristolochic acid (AA is a botanical toxin characterized to associate with the development of renal fibrosis including tubulointerstitial fibrosis. However, whether leptin is upregulated to participate in AA-induced kidney fibrosis remain completely unknown. METHODOLOGY/PRINCIPAL FINDINGS: In this study, leptin expression was increased by sublethal dose of AA in kidney fibroblast NRK49f determined by enzyme-linked immunosorbent assay and Western blot. Data from real-time reverse transcriptase-polymerase chain reaction revealed that leptin was upregulated by AA at transcriptional level. DNA binding activity of CCAAT enhancer binding protein α (C/EBP α, one of the transcription factors for leptin gene, was enhanced in DNA affinity precipitation assay and chromatin immunoprecipitation experiments. Knockdown of C/EBP α expression by small interfering RNA markedly reduced AA-induced leptin expression. Moreover, AA promoted Akt interaction with p-PDK1, and increased phosphorylated activation of Akt. Akt knockdown, and inhibition of Akt signaling by LY294002 and mTOR inhibitor rapamycin reduced leptin expression. Furthermore, treatment of LY294002 or rapamycin significantly suppressed AA-induced C/EBP α DNA-binding activity. These results suggest that Akt and C/EBP α activation were involved in AA-regulated leptin expression. CONCLUSIONS/SIGNIFICANCE: Our findings demonstrate the first that AA could induce secretion and expression of fibrogenic leptin in kidney fibroblasts, which reveal potential involvement of leptin in the progression of kidney fibrosis in aristolochic acid nephropathy.

  9. Hippocampal and cortical expression of gamma-aminobutyric acid transporter 1 and glial fibrillary acidic protein in pentylenetetrazol-induced chronic epileptic rats

    Institute of Scientific and Technical Information of China (English)

    Yi Zeng; Zhong Yang; Xiaodong Long; Chao You

    2009-01-01

    BACKGROUND: Gamma-aminobutyric acid transporter plays an important role in gamma-aminobutyric acid metabolism, and is highly associated with epilepsy seizures.Pathologically, astrocytes release active substances that alter neuronal excitability, and it has been demonstrated that astrocytes play a role in epileptic seizures.OBJECTIVE: To observe changes in gamma-aminobutyric acid transporter 1 and glial fibrillary acidic protein expression in the hippocampus and cortex of the temporal lobe in rats with pentylenetetrazol-induced chronic epilepsy.DESIGN, TIME AND SETTING: Randomized, controlled, animal experiment was performed at the Department of Neurobiology, Third Military University of Chinese PLA between January 2006 and December 2007.MATERIALS: Pentylenetetrazol was purchased from Sigma, USA; rabbit anti-rat gamma-aminobutyric acid transporter 1 and glial fibrillary acidic protein were from Chemicon, USA.METHODS; A total of 40 Sprague Dawley rats were divided into model and control groups. Rat models of chronic epilepsy were created by pentylenetetrazol kindling, and were subdivided into 3-, 7-, and 14-day kindling subgroups.MAIN OUTCOME MEASURES: Gamma-aminobutyric acid transporter 1 and glial fibrillary acidic protein expression, as well as the number of positive cells in the hippocampus and cortex of temporal lobe of rats, were determined by immunohistochemistry and Western blot analyses.RESULTS: Compared with the control group, the number of gamma-aminobutyric acid transporter 1 and glial fibrillary acidic protein -positive cells in the hippocampus and cortex of rats with pentylenetetrazol-induced epilepsy significantly increased, gamma-aminobutyric acid transporter 1 and glial fibrillary acidic protein expression increased after 3 days of kindling, reached a peak on day 7, and remained at elevated levels at day 14 (P < 0.05).CONCLUSION: Astrocytic activation and gamma-aminobutyric acid transporter 1 overexpression may contribute to pentylenetetrazol

  10. Uric acid stimulates endothelin-1 gene expression associated with NADPH oxidase in human aortic smooth muscle cells

    Institute of Scientific and Technical Information of China (English)

    Hung-hsing CHAO; Ju-chi LIU; Jia-wei LIN; Cheng-hsien CHEN; Chieh-hsi WU; Tzu-hurng CHENG

    2008-01-01

    Aim: Recent experimental and human studies have shown that hyperuricemia is associated with hypertension and cardiovascular diseases. Elevated levels of endotheliu-1 (ET-1) has been regarded as one of the most powerful indepen-dent predictors of cardiovascular diseases. For investigating whether uric acidinduced vascular diseases are related to ET-1, the uric acid-induced ET-1 expression in human aortic smooth muscle cells (HASMC) was examined. Methods: Cultured HASMC treated with uric acid, cell proliferation and ET-1 expression were examined. Antioxidant pretreatments on uric acid-induced extracellular signal-regulated kinases (ERK) phosphorylation were carried out to elucidate the redox-sensitive pathway in proliferation and ET-1 gene expression. Results: Uric acid was found to increase HASMC proliferation, ET-1 expression and reactive oxygen species production. The ability of both N-acetylcysteine and apocynin (1-[4-hydroxy-3-methoxyphenyl]ethanone, a NADPH oxidase inhibitor) to inhibit uric acid-induced ET-1 secretion and cell proliferation suggested the involvement of intracellular redox pathways. Furthermore, apocynin, and p47phox small interfering RNA knockdown inhibited ET-1 secretion and cell proliferation induced by uric acid. Inhibition of ERK by U0126 (1,4-diamino-2,3-dicyano-1,4-bis[2-aminophenylthio]butadiene) significantly suppressed uric acid-induced ET-I expression, implicating this pathway in the response to uric acid. In addition, uric acid increased the transcription factor activator protein-1 (AP-1) medi-ated reporter activity, as well as the ERK phosphorylation. Mutational analysis of the ET-1 gene promoter showed that the AP-1 binding site was an important cis-element in uric acid-induced ET-1 gene expression. Conclusion: This is the first observation of ET-1 regulation by uric acid in HASMC, which implicates the important role of uric acid in the vascular changes associated with hypertension and vascular diseases.

  11. Involvement of the G-protein-coupled receptor 4 in RANKL expression by osteoblasts in an acidic environment

    Energy Technology Data Exchange (ETDEWEB)

    Okito, Asuka [Department of Cellular Physiological Chemistry, Tokyo Medical and Dental University, Tokyo (Japan); Department of Orthodontic Science, Tokyo Medical and Dental University, Tokyo (Japan); Nakahama, Ken-ichi, E-mail: nakacell@tmd.ac.jp [Department of Cellular Physiological Chemistry, Tokyo Medical and Dental University, Tokyo (Japan); Akiyama, Masako [Department of Cellular Physiological Chemistry, Tokyo Medical and Dental University, Tokyo (Japan); Ono, Takashi [Department of Orthodontic Science, Tokyo Medical and Dental University, Tokyo (Japan); Morita, Ikuo [Department of Cellular Physiological Chemistry, Tokyo Medical and Dental University, Tokyo (Japan)

    2015-03-06

    Osteoclast activity is enhanced in acidic environments following systemic or local inflammation. However, the regulatory mechanism of receptor activator of NF-κB ligand (RANKL) expression in osteoblasts under acidic conditions is not fully understood. In the present paper, we detected the mRNA expression of the G-protein-coupled receptor (GPR) proton sensors GPR4 and GPR65 (T-cell death-associated gene 8, TDAG8), in osteoblasts. RANKL expression and the cyclic AMP (cAMP) level in osteoblasts were up-regulated under acidic culture conditions. Acidosis-induced up-regulation of RANKL was abolished by the protein kinase A inhibitor H89. To clarify the role of GPR4 in RANKL expression, GPR4 gain and loss of function experiments were performed. Gene knockdown and forced expression of GPR4 caused reduction and induction of RANKL expression, respectively. These results suggested that, at least in part, RANKL expression by osteoblasts in an acidic environment was mediated by cAMP/PKA signaling resulting from GPR4 activation. A comprehensive microarray analysis of gene expression of osteoblasts revealed that, under acidic conditions, the phenotype of osteoblasts was that of an osteoclast supporting cell rather than that of a mineralizing cell. These findings will contribute to a molecular understanding of bone disruption in an acidic environment. - Highlights: • RANKL expression was increased in osteoblasts under acidosis via cAMP/PKA pathway. • GRP4 knockdown resulted in decrease of RANKL expression. • GRP4 overexpression resulted in increase of RANKL expression. • Osteoblast mineralization was reduced under acidic condition.

  12. Glutamine and glutamic acid enhance thyroid-stimulating hormone β subunit mRNA expression in the rat pars tuberalis.

    Science.gov (United States)

    Aizawa, Sayaka; Sakai, Takafumi; Sakata, Ichiro

    2012-03-01

    Thyroid-stimulating hormone (TSH)-producing cells of the pars tuberalis (PT) display distinct characteristics that differ from those of the pars distalis (PD). The mRNA expression of TSHβ and αGSU in PT has a circadian rhythm and is inhibited by melatonin via melatonin receptor type 1; however, the detailed regulatory mechanism for TSHβ expression in the PT remains unclear. To identify the factors that affect PT, a microarray analysis was performed on laser-captured PT tissue to screen for genes coding for receptors that are abundantly expressed in the PT. In the PT, we found high expression of the KA2, which is an ionotropic glutamic acid receptor (iGluR). In addition, the amino acid transporter A2 (ATA2), also known as the glutamine transporter, and glutaminase (GLS), as well as GLS2, were highly expressed in the PT compared to the PD. We examined the effects of glutamine and glutamic acid on TSHβ expression and αGSU expression in PT slice cultures. l-Glutamine and l-glutamic acid significantly stimulated TSHβ expression in PT slices after 2- and 4-h treatments, and the effect of l-glutamic acid was stronger than that of l-glutamine. In contrast, treatment with glutamine and glutamic acid did not affect αGSU expression in the PT or the expression of TSHβ or αGSU in the PD. These results strongly suggest that glutamine is taken up by PT cells through ATA2 and that glutamic acid locally converted from glutamine by Gls induces TSHβ expression via the KA2 in an autocrine and/or paracrine manner in the PT.

  13. Identification, Cloning, and Expression of L-Amino Acid Oxidase from Marine Pseudoalteromonas sp. B3

    Directory of Open Access Journals (Sweden)

    Zhiliang Yu

    2014-01-01

    Full Text Available L-amino acid oxidase (LAAO is attracting more attentions due to its broad and important biological functions. Recently, an LAAO-producing marine microorganism (strain B3 was isolated from the intertidal zone of Dinghai sea area, China. Physiological, biochemical, and molecular identifications together with phylogenetic analysis congruously suggested that it belonged to the genus Pseudoalteromonas. Therefore, it was designated as Pseudoalteromonas sp. B3. Its capability of LAAO production was crossly confirmed by measuring the products of H2O2, a-keto acids, and NH4+ in oxidization reaction. Two rounds of PCR were performed to gain the entire B3-LAAO gene sequence of 1608 bps in length encoding for 535 amino acid residues. This deduced amino acid sequence showed 60 kDa of the calculated molecular mass, supporting the SDS-PAGE result. Like most of flavoproteins, B3-LAAO also contained two conserved typical motifs, GG-motif and βαβ-dinucleotide-binding domain motif. On the other hand, its unique substrate spectra and sequence information suggested that B3-LAAO was a novel LAAO. Our results revealed that it could be functionally expressed in E. coli BL21(DE3 using vectors, pET28b(+ and pET20b(+. However, compared with the native LAAO, the expression level of the recombinant one was relatively low, most probably due to the formation of inclusion bodies. Several solutions are currently being conducted in our lab to increase its expression level.

  14. Effect of estrogen on gene expression of fatty acid synthase in periosteum

    Institute of Scientific and Technical Information of China (English)

    ZHENG Rui-min; LIN Shou-qing; LIU Yong; HUANG Man-ting; GONG Wei-yan; WU Zhi-hong

    2009-01-01

    Background Estrogen deficiency contributes to postmenopausal osteoporosis.Periosteum might be a potential target of estrogen,but the underlying mechanism at gene level is far from being elucidated.The objective of this study was to investigate the correlation between estrogen and fatty acid synthase(FAS)expression in periosteum.Methods Human periosteum cells were cultured in vitro.Expressed genes in the substrated cDNA library were verified using semi-quantitative PCR and real-time PCR.The expression of FAS in periosteum of ovarectomized(OVX)SD rats was investigated.Results FAS gene was most significantly expressed in the subtracted cDNA library of periosteal cells screened by semi-quantitative PCR.Low FAS expression was verified by real-time PCR in the estrogen exposed human periosteum rather than in the control.The estradiol levels were(20.81±12.62)pg/ml,(19.64±4.35)pg/ml and(13.47+1.84)pg/ml in the sham group,the control,and the OVX group,respectively.The estradiol levels in the OVX group was significantly lower(P=0.0386).The FAS gene expression in periosteum in the OVX group,sham group,and control group was 3.09±1.97,1.33±0.47 and 1.51±1.32,respectively.The gene expression in the OVX group was significantly higher (P=0.0372).Conclusion Estrogen modulates FAS gene expression in in vitro human perisoteum as well as in in vivo rat periosteum.

  15. Expression of a cyanobacterial {del}{sup 6}-desaturase gene results in {gamma}-linolenic acid production in transgenic plants

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, A.S.; Thomas, T.L. [Texas A & M Univ., College Station, TX (United States)

    1996-05-01

    Gamma-linolenic acid (GLA), a nutritionally important fatty acid in human and animal diets, is not produced in oil seed crops. Many oil seed plants, however, produce significant quantities of linoleic acid, a fatty acid that could be converted to GLA by the enzyme {del}{sup 6}-desaturase if it were present. As a first step to producing GLA in oil seed crops, we have cloned a cyanobacterial {del}{sup 6}-desaturase gene. Expression of this gene in transgenic tobacco resulted in GLA accumulation. Octadecatetraenoic acid, a highly unsaturated, industrially important fatty acid, was also found in transgenic tobacco plants expressing the cyanobacterial {del}{sup 6}-desaturase. This is the first example of engineering the production of `novel` polyunsaturated fatty acids in transgenic plants. 28 refs., 4 figs., 1 tab.

  16. Eicosapentaenoic acid increases cytochrome P-450 2J2 gene expression and epoxyeicosatrienoic acid production via peroxisome proliferator-activated receptor γ in endothelial cells.

    Science.gov (United States)

    Wang, Dahai; Hirase, Tetsuaki; Nitto, Takeaki; Soma, Masaaki; Node, Koichi

    2009-12-01

    ω-3 fatty acids, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have beneficial effects on cardiovascular diseases. Cytochrome P-450 (CYP) 2J2 that is expressed in endothelial cells metabolizes arachidonic acids to biologically active epoxyeicosatrienoic acids (EETs) that possess anti-inflammatory and anti-thrombotic effects. We studied the effects of EPA and DHA on the expression of CYP 2J2 mRNA by reverse transcription-polymerase chain reaction in cultured human umbilical vein endothelial cells and found that EPA, but not DHA, increased the expression of CYP 2J2 mRNA in a dose-dependent and a time-dependent manner. EPA-induced CYP 2J2 expression was significantly inhibited by pretreatment with a peroxisome proliferator-activated receptor (PPAR) γ antagonist, GW9662. EPA, but not DHA, caused a significant increase in cellular levels of 11,12-dihydroxyeicosatrienoic acid that is a stable metabolite of 11,12-EET, which was blocked by pretreatment with GW9662. These data demonstrate that EPA increases CYP 2J2 mRNA expression and 11,12-EET production via PPARγ in endothelial cells and indicate a novel protective role of EPA and PPARγ against vascular inflammation.

  17. Spinal afferent neurons projecting to the rat lung and pleura express acid sensitive channels

    Directory of Open Access Journals (Sweden)

    Kummer Wolfgang

    2006-07-01

    Full Text Available Abstract Background The acid sensitive ion channels TRPV1 (transient receptor potential vanilloid receptor-1 and ASIC3 (acid sensing ion channel-3 respond to tissue acidification in the range that occurs during painful conditions such as inflammation and ischemia. Here, we investigated to which extent they are expressed by rat dorsal root ganglion neurons projecting to lung and pleura, respectively. Methods The tracer DiI was either injected into the left lung or applied to the costal pleura. Retrogradely labelled dorsal root ganglion neurons were subjected to triple-labelling immunohistochemistry using antisera against TRPV1, ASIC3 and neurofilament 68 (marker for myelinated neurons, and their soma diameter was measured. Results Whereas 22% of pulmonary spinal afferents contained neither channel-immunoreactivity, at least one is expressed by 97% of pleural afferents. TRPV1+/ASIC3- neurons with probably slow conduction velocity (small soma, neurofilament 68-negative were significantly more frequent among pleural (35% than pulmonary afferents (20%. TRPV1+/ASIC3+ neurons amounted to 14 and 10% respectively. TRPV1-/ASIC3+ neurons made up between 44% (lung and 48% (pleura of neurons, and half of them presumably conducted in the A-fibre range (larger soma, neurofilament 68-positive. Conclusion Rat pleural and pulmonary spinal afferents express at least two different acid-sensitive channels that make them suitable to monitor tissue acidification. Patterns of co-expression and structural markers define neuronal subgroups that can be inferred to subserve different functions and may initiate specific reflex responses. The higher prevalence of TRPV1+/ASIC3- neurons among pleural afferents probably reflects the high sensitivity of the parietal pleura to painful stimuli.

  18. Glutamine, glutamate, and arginine-based acid resistance in Lactobacillus reuteri.

    Science.gov (United States)

    Teixeira, Januana S; Seeras, Arisha; Sanchez-Maldonado, Alma Fernanda; Zhang, Chonggang; Su, Marcia Shu-Wei; Gänzle, Michael G

    2014-09-01

    This study aimed to determine whether glutamine deamidation improves acid resistance of Lactobacillus reuteri, and to assess whether arginine, glutamine, and glutamate-mediated acid resistance are redundant or complementary mechanisms of acid resistance. Three putative glutaminase genes, gls1, gls2, and gls3, were identified in L. reuteri 100-23. All three genes were expressed during growth in mMRS and wheat sourdough. L. reuteri consistently over-expressed gls3 and the glutamate decarboxylase gadB. L. reuteri 100-23ΔgadB over-expressed gls3 and the arginine deiminase gene adi. Analysis of the survival of L. reuteri in acidic conditions revealed that arginine conversion is effective at pH of 3.5 while glutamine or glutamate conversion were effective at pH of 2.5. Arginine conversion increased the pHin but not ΔΨ; glutamate decarboxylation had only a minor effect on the pHin but increased the ΔΨ. This study demonstrates that glutamine deamidation increases the acid resistance of L. reuteri independent of glutamate decarboxylase activity. Arginine and glutamine/glutamate conversions confer resistance to lactate at pH of 3.5 and phosphate at pH of 2.5, respectively. Knowledge of L. reuteri's acid resistance improves the understanding of the adaptation of L. reuteri to intestinal ecosystems, and facilitates the selection of probiotic and starter cultures.

  19. Increased cholesterol 7α-hydroxylase expression and size of the bile acid pool in the lactating rat

    Science.gov (United States)

    Wooton-Kee, Clavia Ruth; Cohen, David E.; Vore, Mary

    2008-01-01

    Maximal bile acid secretory rates and expression of bile acid transporters in liver and ileum are increased in lactation, possibly to facilitate increased enterohepatic recirculation of bile acids. We determined changes in the size and composition of the bile acid pool and key enzymes of the bile acid synthetic pathway [cholesterol 7α-hydroxylase (Cyp7a1), sterol 27-hydroxylase (Cyp27a1), and sterol 12α-hydroxylase (Cyp8b1)] in lactating rats relative to female virgin controls. The bile acid pool increased 1.9 to 2.5-fold [postpartum (PP) days 10, 14, and 19–23], compared with controls. A 1.5-fold increase in cholic acids and a 14 to 20% decrease in muricholic acids in lactation significantly increased the hydrophobicity index. In contrast, the hepatic concentration of bile acids and small heterodimer partner mRNA were unchanged in lactation. A 2.8-fold increase in Cyp7a1 mRNA expression at 16 h (10 h of light) demonstrated a shift in the diurnal rhythm at day 10 PP; Cyp7a1 protein expression and cholesterol 7α-hydroxylase activity were significantly increased at this time and remained elevated at day 14 PP but decreased to control levels by day 21 PP. There was an overall decrease in Cyp27a1 mRNA expression and a 20% decrease in Cyp27a1 protein expression, but there was no change in Cyp8b1 mRNA or protein expression at day 10 PP. The increase in Cyp7a1 expression PP provides a mechanism for the increase in the bile acid pool. PMID:18292185

  20. OVER-EXPRESSION OF GENE ENCODING FATTY ACID METABOLIC ENZYMES IN FISH

    Directory of Open Access Journals (Sweden)

    Alimuddin Alimuddin

    2008-12-01

    Full Text Available Eicosapentaenoic acid (EPA, 20:5n-3 and docosahexaenoic acid (DHA, 22:6n-3 have important nutritional benefits in humans. EPA and DHA are mainly derived from fish, but the decline in the stocks of major marine capture fishes could result in these fatty acids being consumed less. Farmed fish could serve as promising sources of EPA and DHA, but they need these fatty acids in their diets. Generation of fish strains that are capable of synthesizing enough amounts of EPA/DHA from the conversion of α-linolenic acid (LNA, 18:3n-3 rich oils can supply a new EPA/DHA source. This may be achieved by over-expression of genes encoding enzymes involved in HUFA biosynthesis. In aquaculture, the successful of this technique would open the possibility to reduce the enrichment of live food with fish oils for marine fish larvae, and to completely substitute fish oils with plant oils without reducing the quality of flesh in terms of EPA and DHA contents. Here, three genes, i.e. Δ6-desaturase-like (OmΔ6FAD, Δ5-desaturase-like (OmΔ5FAD and elongase-like (MELO encoding EPA/DHA metabolic enzymes derived from masu salmon (Oncorhynchus masou were individually transferred into zebrafish (Danio rerio as a model to increase its ability for synthesizing EPA and DHA. Fatty acid analysis showed that EPA content in whole body of the second transgenic fish generation over-expressing OmΔ6FAD gene was 1.4 fold and that of DHA was 2.1 fold higher (P<0.05 than those in non-transgenic fish. The EPA content in whole body of transgenic fish over-expressing OmΔ5FAD gene was 1.21-fold, and that of DHA was 1.24-fold higher (P<0.05 than those in nontransgenic fish. The same patterns were obtained in transgenic fish over-expressing MELO gene. EPA content was increased by 1.30-fold and DHA content by 1.33-fold higher (P<0.05 than those in non-transgenic fish. The results of studies demonstrated that fatty acid content of fish can be enhanced by over-expressing

  1. Relative gene expression in acid-adapted Escherichia coli O157:H7 during lactoperoxidase and lactic acid challenge in Tryptone Soy Broth.

    Science.gov (United States)

    Parry-Hanson, Angela A; Jooste, Piet J; Buys, Elna M

    2010-09-20

    Cross-protection of acid-adapted Escherichia coli O157:H7 against inimical stresses is mediated by the glucose-repressed sigma factor RpoS. However, many food systems in which E. coli O157:H7 occurs are complex and contain glucose. This study was aimed at investigating the contribution of acid and lactoperoxidase (LP)-inducible genes to cross-protection of E. coli O157:H7 against LP system and lactic acid (LA) in Tryptone Soy Broth (TSB). Acid-adapted and non-adapted E. coli O157:H7 were challenged to activated LP and LA at pH 4.0 and 5.0 in TSB for 6h at 25°C followed by expression of acid and LP-inducible genes. Acid-adapted E. coli showed cross-protection against activated LP and LA. All the acid-inducible genes tested were repressed at pH 4.0 with or without activated LP system. At pH 7.4, gadA, ompC and ompF were induced in acid-adapted cells. Induction of corA occurred in non-adapted cells but was repressed in acid-adapted cells. Although acid-inducible genes were repressed at pH 4.0, high resistance of acid-adapted cells indicates that expression of acid-inducible genes occurred during acid adaptation and not the actual challenge. Repression of rpoS indicates that RpoS-independent systems contribute to cross-protection in acid-adapted E. coli O157:H7.

  2. Gene expression signature of DMBA-induced hamster buccal pouch carcinomas: modulation by chlorophyllin and ellagic acid.

    Directory of Open Access Journals (Sweden)

    Ramamurthi Vidya Priyadarsini

    Full Text Available Chlorophyllin (CHL, a water-soluble, semi-synthetic derivative of chlorophyll and ellagic acid (EA, a naturally occurring polyphenolic compound in berries, grapes, and nuts have been reported to exert anticancer effects in various human cancer cell lines and in animal tumour models. The present study was undertaken to examine the mechanism underlying chemoprevention and changes in gene expression pattern induced by dietary supplementation of chlorophyllin and ellagic acid in the 7,12-dimethylbenz[a]anthracene (DMBA-induced hamster buccal pouch (HBP carcinogenesis model by whole genome profiling using pangenomic microarrays. In hamsters painted with DMBA, the expression of 1,700 genes was found to be altered significantly relative to control. Dietary supplementation of chlorophyllin and ellagic acid modulated the expression profiles of 104 and 37 genes respectively. Microarray analysis also revealed changes in the expression of TGFβ receptors, NF-κB, cyclin D1, and matrix metalloproteinases (MMPs that may play a crucial role in the transformation of the normal buccal pouch to a malignant phenotype. This gene expression signature was altered on treatment with chlorophyllin and ellagic acid. Our study has also revealed patterns of gene expression signature specific for chlorophyllin and ellagic acid exposure. Thus dietary chlorophyllin and ellagic acid that can reverse gene expression signature associated with carcinogenesis are novel candidates for cancer prevention and therapy.

  3. Gene expression signature of DMBA-induced hamster buccal pouch carcinomas: modulation by chlorophyllin and ellagic acid.

    Science.gov (United States)

    Vidya Priyadarsini, Ramamurthi; Kumar, Neeraj; Khan, Imran; Thiyagarajan, Paranthaman; Kondaiah, Paturu; Nagini, Siddavaram

    2012-01-01

    Chlorophyllin (CHL), a water-soluble, semi-synthetic derivative of chlorophyll and ellagic acid (EA), a naturally occurring polyphenolic compound in berries, grapes, and nuts have been reported to exert anticancer effects in various human cancer cell lines and in animal tumour models. The present study was undertaken to examine the mechanism underlying chemoprevention and changes in gene expression pattern induced by dietary supplementation of chlorophyllin and ellagic acid in the 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis model by whole genome profiling using pangenomic microarrays. In hamsters painted with DMBA, the expression of 1,700 genes was found to be altered significantly relative to control. Dietary supplementation of chlorophyllin and ellagic acid modulated the expression profiles of 104 and 37 genes respectively. Microarray analysis also revealed changes in the expression of TGFβ receptors, NF-κB, cyclin D1, and matrix metalloproteinases (MMPs) that may play a crucial role in the transformation of the normal buccal pouch to a malignant phenotype. This gene expression signature was altered on treatment with chlorophyllin and ellagic acid. Our study has also revealed patterns of gene expression signature specific for chlorophyllin and ellagic acid exposure. Thus dietary chlorophyllin and ellagic acid that can reverse gene expression signature associated with carcinogenesis are novel candidates for cancer prevention and therapy.

  4. The first step in the biosynthesis of cocaine in Erythroxylum coca: the characterization of arginine and ornithine decarboxylases.

    Science.gov (United States)

    Docimo, Teresa; Reichelt, Michael; Schneider, Bernd; Kai, Marco; Kunert, Grit; Gershenzon, Jonathan; D'Auria, John C

    2012-04-01

    Despite the long history of cocaine use among humans and its social and economic significance today, little information is available about the biochemical and molecular aspects of cocaine biosynthesis in coca (Erythroxylum coca) in comparison to what is known about the formation of other pharmacologically-important tropane alkaloids in species of the Solanaceae. In this work, we investigated the site of cocaine biosynthesis in E. coca and the nature of the first step. The two principal tropane alkaloids of E. coca, cocaine and cinnamoyl cocaine, were present in highest concentrations in buds and rolled leaves. These are also the organs in which the rate of alkaloid biosynthesis was the highest based on the incorporation of ¹³CO₂. In contrast, tropane alkaloids in the Solanaceae are biosynthesized in the roots and translocated to the leaves. A collection of EST sequences from a cDNA library made from young E. coca leaves was employed to search for genes encoding the first step in tropane alkaloid biosynthesis. Full-length cDNA clones were identified encoding two candidate enzymes, ornithine decarboxylase (ODC) and arginine decarboxylase (ADC), and the enzymatic activities of the corresponding proteins confirmed by heterologous expression in E. coli and complementation of a yeast mutant. The transcript levels of both ODC and ADC genes were highest in buds and rolled leaves and lower in other organs. The levels of both ornithine and arginine themselves showed a similar pattern, so it was not possible to assign a preferential role in cocaine biosynthesis to one of these proteins.

  5. Saturated fatty acids stimulate and insulin suppresses CIDE-A expression in bovine mammary epithelial cells.

    Science.gov (United States)

    Yonezawa, Tomo; Haga, Satoshi; Kobayashi, Yosuke; Katoh, Kazuo; Obara, Yoshiaki

    2009-07-10

    Cell death-inducing DNA fragmentation factor-alpha-like effector A (CIDE-A) was first identified by its sequence homology with the N-terminal domain of DNA fragmentation factor (DFF). CIDE-A negatively regulates the activity of uncoupling protein 1 (UCP1) in brown adipose tissue. CIDE-A and UCP1 mRNA were detected by RT-PCR in cloned bovine mammary epithelial cells (bMEC) and lactating bovine mammary glands. Physiological concentrations of saturated fatty acids (stearate and palmitate), but not unsaturated fatty acids (oleate and linoleate) induced up-regulation of CIDE-A mRNA in bMEC. Treatment with insulin (5-10 ng/ml) induced down-regulation of CIDE-A and UCP1. The expression levels of CIDE-A and UCP1 mRNA in bovine mammary glands at various stages of the lactation cycle were determined by quantitative RT-PCR analysis. CIDE-A mRNA expression at peak lactation (2 months after parturition) was significantly higher than at dry off and non-pregnancy but not late lactation. These results suggest that CIDE-A and UCP1 are regulated by insulin and/or fatty acids in mammary epithelial cells and lactating mammary glands, and thereby play an important role in lipid and energy metabolism.

  6. Curcumin-attenuated trinitrobenzene sulphonic acid induces chronic colitis by inhibiting expression of cyclooxygenase-2

    Institute of Scientific and Technical Information of China (English)

    Hua Jiang; Chang-Sheng Deng; Ming Zhang; Jian Xia

    2006-01-01

    AIM: To explore the possible mechanisms of curcumin in rat colitis induced by trinitrobenzene sulfonic (TNBS) acid. METHODS: Rats with TNBS acid-induced colitis were treated with curcumin (30 mg/kg or 60 mg/kg per day ip). Changes of body weight and histological scores as well as survival rate were evaluated. Leukocyte infiltration was detected by myeloperoxidase (MPO)activity assay. The expression of cyclooxygenase-2(COX-2) was detected by RT-PCR and Western blot.Inflammation cytokines were determined by RT-PCR.Local concentration of prostaglandin E2 (PGE2) in colon mucosa was determined by ELISA.RESULTS: Curcumin improved survival rate and histological image, decreased the macroscopic scores and MPO activity. Also curcumin reduced the expression of COX-2 and inflammation cytokines. In addition,treatment with curcumin increased the PGE2 level.CONCLUSION: Curcumin has therapeutic effects on TNBS acid-induced colitis, the mechanisms seem to be related to COX-2 inhibition and PGE2 improvement.

  7. Catalytic properties of the archaeal S-adenosylmethionine decarboxylase from Methanococcus jannaschii.

    Science.gov (United States)

    Lu, Zichun J; Markham, George D

    2004-01-02

    S-Adenosylmethionine decarboxylase (AdoMetDC) is a pyruvoyl cofactor-dependent enzyme that participates in polyamine biosynthesis. AdoMetDC from the Archaea Methanococcus jannaschii is a prototype for a recently discovered class that is not homologous to the eucaryotic enzymes or to a distinct group of microbial enzymes. M. jannaschii AdoMetDC has a Km of 95 microm and the turnover number (kcat) of 0.0075 s(-1) at pH 7.5 and 22 degrees C. The turnover number increased approximately 38-fold at a more physiological temperature of 80 degrees C. AdoMetDC was inactivated by treatment with the imine reductant NaCNBH3 only in the presence of substrate. Mass spectrometry of the inactivated protein showed modification solely of the pyruvoyl-containing subunit, with a mass increase corresponding to reduction of a Schiff base adduct with decarboxylated AdoMet. The presteady state time course of the AdoMetDC reaction revealed a burst of product formation; thus, a step after CO2 formation is rate-limiting in turnover. Comparable D2O kinetic isotope effects of were seen on the first turnover (1.9) and on kcat/Km (1.6); there was not a significant D2O isotope effect on kcat, suggesting that product release is rate-limiting in turnover. The pH dependence of the steady state rate showed participation of acid and basic groups with pK values of 5.3 and 8.2 for kcat and 6.5 and 8.3 for kcat/Km, respectively. The competitive inhibitor methylglyoxal bis(guanylhydrazone) binds at a single site per (alphabeta) heterodimer. UV spectroscopic studies show that methylglyoxal bis(guanylhydrazone) binds as the dication with a 23 microm dissociation constant. Studies with substrate analogs show a high specificity for AdoMet.

  8. Epigenetic signature of panic disorder: a role of glutamate decarboxylase 1 (GAD1) DNA hypomethylation?

    Science.gov (United States)

    Domschke, Katharina; Tidow, Nicola; Schrempf, Marie; Schwarte, Kathrin; Klauke, Benedikt; Reif, Andreas; Kersting, Anette; Arolt, Volker; Zwanzger, Peter; Deckert, Jürgen

    2013-10-01

    Glutamate decarboxylases (GAD67/65; GAD1/GAD2) are crucially involved in gamma-aminobutyric acid (GABA) synthesis and thus were repeatedly suggested to play an important role in the pathogenesis of anxiety disorders. In the present study, DNA methylation patterns in the GAD1 and GAD2 promoter and GAD1 intron 2 regions were investigated for association with panic disorder, with particular attention to possible effects of environmental factors. Sixty-five patients with panic disorder (f=44, m=21) and 65 matched healthy controls were analyzed for DNA methylation status at 38 GAD1 promoter/intron2 and 10 GAD2 promoter CpG sites via direct sequencing of sodium bisulfate treated DNA extracted from blood cells. Recent positive and negative life events were ascertained. Patients and controls were genotyped for GAD1 rs3762556, rs3791878 and rs3762555, all of which are located in the analyzed promoter region. Patients with panic disorder exhibited significantly lower average GAD1 methylation than healthy controls (p<0.001), particularly at three CpG sites in the promoter as well as in intron 2. The occurrence of negative life events was correlated with relatively decreased average methylation mainly in the female subsample (p=0.01). GAD1 SNP rs3762555 conferred a significantly lower methylation at three GAD1 intron 2 CpG sites (p<0.001). No differential methylation was observed in the GAD2 gene. The present pilot data suggest a potentially compensatory role of GAD1 gene hypomethylation in panic disorder possibly mediating the influence of negative life events and depending on genetic variation. Future studies are warranted to replicate the present finding in independent samples, preferably in a longitudinal design.

  9. Structural Basis for Nucleotide Binding and Reaction Catalysis in Mevalonate Diphosphate Decarboxylase

    Energy Technology Data Exchange (ETDEWEB)

    Barta, Michael L.; McWhorter, William J.; Miziorko, Henry M.; Geisbrecht, Brian V. (UMKC)

    2012-09-17

    Mevalonate diphosphate decarboxylase (MDD) catalyzes the final step of the mevalonate pathway, the Mg{sup 2+}-ATP dependent decarboxylation of mevalonate 5-diphosphate (MVAPP), producing isopentenyl diphosphate (IPP). Synthesis of IPP, an isoprenoid precursor molecule that is a critical intermediate in peptidoglycan and polyisoprenoid biosynthesis, is essential in Gram-positive bacteria (e.g., Staphylococcus, Streptococcus, and Enterococcus spp.), and thus the enzymes of the mevalonate pathway are ideal antimicrobial targets. MDD belongs to the GHMP superfamily of metabolite kinases that have been extensively studied for the past 50 years, yet the crystallization of GHMP kinase ternary complexes has proven to be difficult. To further our understanding of the catalytic mechanism of GHMP kinases with the purpose of developing broad spectrum antimicrobial agents that target the substrate and nucleotide binding sites, we report the crystal structures of wild-type and mutant (S192A and D283A) ternary complexes of Staphylococcus epidermidis MDD. Comparison of apo, MVAPP-bound, and ternary complex wild-type MDD provides structural information about the mode of substrate binding and the catalytic mechanism. Structural characterization of ternary complexes of catalytically deficient MDD S192A and D283A (k{sub cat} decreased 10{sup 3}- and 10{sup 5}-fold, respectively) provides insight into MDD function. The carboxylate side chain of invariant Asp{sup 283} functions as a catalytic base and is essential for the proper orientation of the MVAPP C3-hydroxyl group within the active site funnel. Several MDD amino acids within the conserved phosphate binding loop ('P-loop') provide key interactions, stabilizing the nucleotide triphosphoryl moiety. The crystal structures presented here provide a useful foundation for structure-based drug design.

  10. Time course degeneration and expression of glial fibrillary acidic protein in mer-knockout mice

    Institute of Scientific and Technical Information of China (English)

    LIANG Xiao-ying; WANG Huai-zhou; WANG Ning-li

    2010-01-01

    Background Muller cells in the mammalian retina normally express low levels of glial fibrillary acidic protein (GFAP); however, its expression is upregulated in response to the loss of retinal neurons. The change in expression of GFAP is one of the earliest indicators of retinal damage and is correlated with the time course of disease. The aim of this study was to investigate the time course of degeneration and the expression of GFAP in the retina of mer knockout mice. Methods A total of 30 mer knockout mice, aged from 15-20 days to 1 year and 32 age-matched wild type mice as controls were tested. Immunohistochemistry was used to show the expression of GFAP in the central and peripheral retina of mer knockout and control mice at postnatal age of 15 days (P15d), 20 days (P20d), 4 weeks (P4w), 6 weeks (P6w), 8 weeks (P8w), 3 months (P3m), 6 months (P6m) and 1 years (P1y).Results The expression of GFAP in the central and peripheral retina of wild type mice was limited to the retinal ganglion cell and nerve fiber layers. In the central retina of mer knockout mice, GFAP expression was upregulated at P4w and GFAP immunolabelling penetrates across the entire thickness of the retina at P8w; whereas in the peripheral retina, the GFAP expression was upregulated at P20d and GFAP immunolabelling penetrates the entire retina after P4w. Conclusions Increased expression of GFAP in Muller cells of mer knockout mice occur at P20d in the peripheral retina and P4w in the central retina. GFAP expression in Muller cells appears to be a secondary response to the loss of retinal neurons. Increased expression of GFAP may occur prior to any detectable morphological changes in the retina. This study suggests that the loss of retinal neurons may begin in the early stages of retinitis pigmentosa, prior to the discovery of any morphological changes in the retina.

  11. Expression and characterization of an enantioselective antigen-binding fragment directed against α-amino acids

    Science.gov (United States)

    Eleniste, Pierre P.; Hofstetter, Heike; Hofstetter, Oliver

    2013-01-01

    This work describes the design and expression of a stereoselective Fab that possesses binding properties comparable to those displayed by the parent monoclonal antibody. Utilizing mRNA from hybridoma clones that secrete a stereoselective anti-L-amino acid antibody, a corresponding biotechnologically produced Fab was generated. For that, appropriate primers were designed based on extensive literature and databank searches. Using these primers in PCR resulted in successful amplification of the VH, VL, CL and CH1 gene fragments. Overlap PCR was utilized to combine the VH and CH1 sequences and the VL and CL sequences, respectively, to obtain the genes encoding the HC and LC fragments. These sequences were separately cloned into the pEXP5-CT/TOPO expression vector and used for transfection of BL21(DE3) cells. Separate expression of the two chains, followed by assembly in a refolding buffer, yielded an Fab that was demonstrated to bind to L-amino acids but not to recognize the corresponding D-enantiomers. PMID:23827208

  12. Purification, Gene Cloning and Expression of an Acidic Phospholipase A2 from Agkistrodon shedaoensis Zhao

    Institute of Scientific and Technical Information of China (English)

    Qian JIN; Li-Xia YANG; Hao-Mang JIAO; Bin LU; Yu-Qun WU; Yuan-Cong ZHOU

    2004-01-01

    A protein with the activity of phospholipase A2 named asAPLA2 was purified to homogeneity from the venom of Agkistrodon shedaoensis Zhao through DEAE-Sepharose CL-6B anion exchange column,Source S and Mono Q FPLC. Its molecular weight was estimated as 19 kD by SDS-PAGE and its pI was about 3.5 by IEF analysis. It inhibits the platelet aggregation that was induced by 1 μmol/L ADP, and the IC50 was determined to be 6 μmol/L. Degenerate primer was designed and synthesized according to the Nterminal amino acid sequence of asAPLA2. Its full-length cDNA was cloned by RT-PCR from the total RNA extracted from the snake venom gland. According to the deduced amino acid sequence, its molecular weight and pI are determined to be 13,649 and 4.39 respectively as calculated by DNAclub and DNAstar softwares.The gene was then cloned into the expression plasmid pET-40b(+) and expressed in E. Coli BL21(DE3).Western blot analysis indicated that the expressed protein cross-reacted with the antibody against the nativeenzyme.

  13. Purification, Gene Cloning and Expression of an Acidic Phospholipase A2 from Agkistrodon shedaoensis Zhao

    Institute of Scientific and Technical Information of China (English)

    QianJIN; Li-XiaYANG; Hao-MangJIAO; BinLU; Yu-QunWU; Yuan-CongZHOU

    2004-01-01

    A protein with the activity of phospholipase A2 named asAPLA2 was pmified to homogeneity from the venom of Agkistrodon shedaoensis Zhao through DEAE-Sepharose CL-6B anion exchange column,Source S and Mono Q FPLC. Its molecular weight was estimated as 19kD by SDS-PAGE and its pI was about 3.5 by IEF analysis. It inhibits the platelet aggregation that was induced by 1μmol/L ADP, and the IC50 was determined to be 6μmol/L. Degenerate primer was designed and synthesized according to the Nterminal amino acid sequence of asAPLA2. Its full-length cDNA was cloned by RT-PCR from the total RNA extracted from the snake venom gland. According to the deduced amino acid sequence, its molecular weight and pI are determined to be 13,649 and 4.39 respectively as calculated by DNAclub and DNAstar softwares.The gene was then cloned into the expression plasmid pET-40b(+) and expressed in E.coli BL21(DE3).Western blot analysis indicated that the expressed protein cross-reacted with the antibc dy against the native enzyme.

  14. Elevated Expression of Acid-Sensing Ion Channel 3 Inhibits Epilepsy via Activation of Interneurons.

    Science.gov (United States)

    Cao, Qingqing; Wang, Wei; Gu, Juan; Jiang, Guohui; Bian, Xiling; Wang, Kewei; Xu, Zucai; Li, Jie; Chen, Guojun; Wang, Xuefeng

    2016-01-01

    Recent studies have indicated that acid-sensing ion channels may play a significant role in the termination of epilepsy. In particular, acid-sensing ion channel 3 (ASIC3) is expressed in the central nervous system and is most sensitive to extracellular pH. However, whether ASIC3 plays a role in epilepsy is unknown. In this study, qRT-PCR, Western blot, immunohistochemistry, double immunofluorescence labeling, and slice recordings were used. We first detected elevated ASIC3 expression patterns in the brains of temporal lobe epilepsy patients and epileptic rats. ASIC3 was expressed in neurons and glia in both humans and in an experimental model of epilepsy, and ASIC3 was colocalized with inhibitory GABAergic interneurons. By blocking ASIC3 with its antagonist APETx2, we observed that injected APETx2 shortened the latency to seizure and increased the incidence of generalized tonic clonic seizure compared to the control group in models of both pilocarpine- and pentylenetetrazole (PTZ)-induced seizures. Additionally, blocking ASIC3 significantly decreased the frequency of action potential (AP) firing in interneurons. Moreover, APETx2 significantly reduced the amplitudes and frequencies of miniature inhibitory postsynaptic currents (mIPSCs) while showed no differences with the APETx2 + bicuculline group and the bicuculline group. These findings suggest that elevated levels of ASIC3 may serve as an anti-epileptic mechanism via postsynaptic mechanisms in interneurons. It could represent a novel therapeutic strategy for epilepsy treatment.

  15. Acetic acid increases the phage-encoded enterotoxin A expression in Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    da Silva Ayla

    2010-05-01

    Full Text Available Abstract Background The effects of acetic acid, a common food preservative, on the bacteriophage-encoded enterotoxin A (SEA expression and production in Staphylococcus aureus was investigated in pH-controlled batch cultures carried out at pH 7.0, 6.5, 6.0, 5.5, 5.0, and 4.5. Also, genomic analysis of S. aureus strains carrying sea was performed to map differences within the gene and in the temperate phage carrying sea. Results The sea expression profile was similar from pH 7.0 to 5.5, with the relative expression peaking in the transition between exponential and stationary growth phase and falling during stationary phase. The levels of sea mRNA were below the detection limit at pH 5.0 and 4.5, confirmed by very low SEA levels at these pH values. The level of relative sea expression at pH 6.0 and 5.5 were nine and four times higher, respectively, in the transitional phase than in the exponential growth phase, compared to pH 7.0 and pH 6.5, where only a slight increase in relative expression in the transitional phase was observed. Furthermore, the increase in sea expression levels at pH 6.0 and 5.5 were observed to be linked to increased intracellular sea gene copy numbers and extracellular sea-containing phage copy numbers. The extracellular SEA levels increased over time, with highest levels produced at pH 6.0 in the four growth phases investigated. Using mitomycin C, it was verified that SEA was at least partially produced as a consequence of prophage induction of the sea-phage in the three S. aureus strains tested. Finally, genetic analysis of six S. aureus strains carrying the sea gene showed specific sea phage-groups and two versions of the sea gene that may explain the different sea expression and production levels observed in this study. Conclusions Our findings suggest that the increased sea expression in S. aureus caused by acetic acid induced the sea-encoding prophage, linking SEA production to the lifecycle of the phage.

  16. Expression pattern of peptide and amino acid genes in digestive tract of transporter juvenile turbot ( Scophthalmus maximus L.)

    Science.gov (United States)

    Xu, Dandan; He, Gen; Mai, Kangsen; Zhou, Huihui; Xu, Wei; Song, Fei

    2016-04-01

    Turbot ( Scophthalmus maximus L.), a carnivorous fish species with high dietary protein requirement, was chosen to examine the expression pattern of peptide and amino acid transporter genes along its digestive tract which was divided into six segments including stomach, pyloric caeca, rectum, and three equal parts of the remainder of the intestine. The results showed that the expression of two peptide and eleven amino acid transporters genes exhibited distinct patterns. Peptide transporter 1 (PepT1) was rich in proximal intestine while peptide transporter 2 (PepT2) was abundant in distal intestine. A number of neutral and cationic amino acid transporters expressed richly in whole intestine including B0-type amino acid transporter 1 (B0AT1), L-type amino acid transporter 2 (LAT2), T-type amino acid transporter 1 (TAT1), proton-coupled amino acid transporter 1 (PAT1), y+L-type amino acid transporter 1 (y+LAT1), and cationic amino acid transporter 2 (CAT2) while ASC amino acid transporter 2 (ASCT2), sodium-coupled neutral amino acid transporter 2 (SNAT2), and y+L-type amino acid transporter 2 (y+LAT2) abundantly expressed in stomach. In addition, system b0,+ transporters (rBAT and b0,+AT) existed richly in distal intestine. These findings comprehensively characterized the distribution of solute carrier family proteins, which revealed the relative importance of peptide and amino acid absorption through luminal membrane. Our findings are helpful to understand the mechanism of the utilization of dietary protein in fish with a short digestive tract.

  17. Genome‐wide gene expression changes in an industrial clavulanic acid overproduction strain of Streptomyces clavuligerus

    Science.gov (United States)

    Medema, Marnix H.; Alam, Mohammad T.; Heijne, Wilbert H. M.; van den Berg, Marco A.; Müller, Ulrike; Trefzer, Axel; Bovenberg, Roel A. L.; Breitling, Rainer; Takano, Eriko

    2011-01-01

    Summary To increase production of the important pharmaceutical compound clavulanic acid, a β‐lactamase inhibitor, both random mutagenesis approaches and rational engineering of Streptomyces clavuligerus strains have been extensively applied. Here, for the first time, we compared genome‐wide gene expression of an industrial S. clavuligerus strain, obtained through iterative mutagenesis, with that of the wild‐type strain. Intriguingly, we found that the majority of the changes contributed not to a complex rewiring of primary metabolism but consisted of a simple upregulation of various antibiotic biosynthesis gene clusters. A few additional transcriptional changes in primary metabolism at key points seem to divert metabolic fluxes to the biosynthetic precursors for clavulanic acid. In general, the observed changes largely coincide with genes that have been targeted by rational engineering in recent years, yet the presence of a number of previously unexplored genes clearly demonstrates that functional genomic analysis can provide new leads for strain improvement in biotechnology. PMID:21342474

  18. Genome-wide gene expression changes in an industrial clavulanic acid overproduction strain of Streptomyces clavuligerus.

    Science.gov (United States)

    Medema, Marnix H; Alam, Mohammad T; Heijne, Wilbert H M; van den Berg, Marco A; Müller, Ulrike; Trefzer, Axel; Bovenberg, Roel A L; Breitling, Rainer; Takano, Eriko

    2011-03-01

    To increase production of the important pharmaceutical compound clavulanic acid, a β-lactamase inhibitor, both random mutagenesis approaches and rational engineering of Streptomyces clavuligerus strains have been extensively applied. Here, for the first time, we compared genome-wide gene expression of an industrial S. clavuligerus strain, obtained through iterative mutagenesis, with that of the wild-type strain. Intriguingly, we found that the majority of the changes contributed not to a complex rewiring of primary metabolism but consisted of a simple upregulation of various antibiotic biosynthesis gene clusters. A few additional transcriptional changes in primary metabolism at key points seem to divert metabolic fluxes to the biosynthetic precursors for clavulanic acid. In general, the observed changes largely coincide with genes that have been targeted by rational engineering in recent years, yet the presence of a number of previously unexplored genes clearly demonstrates that functional genomic analysis can provide new leads for strain improvement in biotechnology.

  19. Comparative proteomic analysis of differentially expressed proteins in β-aminobutyric acid enhanced Arabidopsis thaliana tolerance to simulated acid rain.

    Science.gov (United States)

    Liu, Tingwu; Jiang, Xinwu; Shi, Wuliang; Chen, Juan; Pei, Zhenming; Zheng, Hailei

    2011-05-01

    Acid rain is a worldwide environmental issue that has seriously destroyed forest ecosystems. As a highly effective and broad-spectrum plant resistance-inducing agent, β-aminobutyric acid could elevate the tolerance of Arabidopsis when subjected to simulated acid rain. Using comparative proteomic strategies, we analyzed 203 significantly varied proteins of which 175 proteins were identified responding to β-aminobutyric acid in the absence and presence of simulated acid rain. They could be divided into ten groups according to their biological functions. Among them, the majority was cell rescue, development and defense-related proteins, followed by transcription, protein synthesis, folding, modification and destination-associated proteins. Our conclusion is β-aminobutyric acid can lead to a large-scale primary metabolism change and simultaneously activate antioxidant system and salicylic acid, jasmonic acid, abscisic acid signaling pathways. In addition, β-aminobutyric acid can reinforce physical barriers to defend simulated acid rain stress.

  20. Substrate activation of brewers' yeast pyruvate decarboxylase is abolished by mutation of cysteine 221 to serine.

    Science.gov (United States)

    Baburina, I; Gao, Y; Hu, Z; Jordan, F; Hohmann, S; Furey, W

    1994-05-10

    Brewers' yeast pyruvate decarboxylase (EC 4.1.1.1), a thiamin diphosphate and Mg(II)-dependent enzyme, isolated from Saccharomyces cerevisiae possesses four cysteines/subunit at positions 69, 152, 221, and 222. Earlier studies conducted on a variant of the enzyme with a single Cys at position 221 (derived from a gene that was the product of spontaneous fusion) showed that this enzyme is still subject to substrate activation [Zeng, X., Farrenkopf, B., Hohmann, S., Jordan, F., Dyda, F., & Furey, W. (1993) Biochemistry 32, 2704-2709], indicating that if Cys was responsible for this activation, it had to be C221. To further test the hypothesis, the C221S and C222S single and the C221S-C222S double mutants were constructed. It is clearly shown that the mutation at C221, but not at C222, leads to abolished substrate activation according to a number of kinetic criteria, both steady state and pre steady state. On the basis of the three-dimensional structure of the enzyme [Dyda, F., Furey, W., Swaminathan, S., Sax, M., Farrenkopf, B., Jordan, F. (1993) Biochemistry 32, 6165-6170], it is obvious that while C221 is located on the beta domain, whereas thiamin diphosphate is wedged at the interface of the alpha and gamma domains, addition of pyruvate or pyruvamide as a hemiketal adduct to the sulfur of C221 can easily bridge the gap between the beta and alpha domains. In fact, residues in one or both domains must be dislocated by this adduct formation. It is very likely that regulation as expressed in substrate activation is transmitted via this direct contact made between the two domains in the presence of the activator.(ABSTRACT TRUNCATED AT 250 WORDS)

  1. Helicobacter pylori virulence factors affecting gastric proton pump expression and acid secretion.

    Science.gov (United States)

    Hammond, Charles E; Beeson, Craig; Suarez, Giovanni; Peek, Richard M; Backert, Steffen; Smolka, Adam J

    2015-08-01

    Acute Helicobacter pylori infection of gastric epithelial cells and human gastric biopsies represses H,K-ATPase α subunit (HKα) gene expression and inhibits acid secretion, causing transient hypochlorhydria and supporting gastric H. pylori colonization. Infection by H. pylori strains deficient in the cag pathogenicity island (cag PAI) genes cagL, cagE, or cagM, which do not transfer CagA into host cells or induce interleukin-8 secretion, does not inhibit HKα expression, nor does a cagA-deficient strain that induces IL-8. To test the hypothesis that virulence factors other than those mediating CagA translocation or IL-8 induction participate in HKα repression by activating NF-κB, AGS cells transfected with HKα promoter-Luc reporter constructs containing an intact or mutated NF-κB binding site were infected with wild-type H. pylori strain 7.13, isogenic mutants lacking cag PAI genes responsible for CagA translocation and/or IL-8 induction (cagA, cagζ, cagε, cagZ, and cagβ), or deficient in genes encoding two peptidoglycan hydrolases (slt and cagγ). H. pylori-induced AGS cell HKα promoter activities, translocated CagA, and IL-8 secretion were measured by luminometry, immunoblotting, and ELISA, respectively. Human gastric biopsy acid secretion was measured by microphysiometry. Taken together, the data showed that HKα repression is independent of IL-8 expression, and that CagA translocation together with H. pylori transglycosylases encoded by slt and cagγ participate in NF-κB-dependent HKα repression and acid inhibition. The findings are significant because H. pylori factors other than CagA and IL-8 secretion are now implicated in transient hypochlorhydria which facilitates gastric colonization and potential triggering of epithelial progression to neoplasia.

  2. Are Gene Expression Microarray Analyses Reliable? A Review of Studies of Retinoic Acid Responsive Genes

    Institute of Scientific and Technical Information of China (English)

    Peter J. van der Spek; Andreas Kremer; Lynn Murry; Michael G. Walker

    2003-01-01

    Microarray analyses of gene expression are widely used, but reports of the same analyses by different groups give widely divergent results, and raise questions regarding reproducibility and reliability. We take as an example recent published reports on microarray experiments that were designed to identify retinoic acid responsive genes. These reports show substantial differences in their results. In this article, we review the methodology, results, and potential causes of differences in these applications of microarrays. Finally, we suggest practices to improve the reliability and reproducibility of microarray experiments.

  3. Are Gene Expression Microarray Analyses Reliable? A Review of Studies of Retinoic Acid Responsive Genes

    Institute of Scientific and Technical Information of China (English)

    PeterJ.vanderSpek; AndreasKremer; LynnMurry; MichaelG.Walker

    2003-01-01

    Microarray analyses of gene expression are widely used,but reports of the same analyses by different groups give widely divergent results,and raise questions regarding reproducibility and reliability.We take as an example recent published reports on microarray experiments that were designed to identify retinoic acid responsive genes.These reports show substantial differences in their results.In this article,we review the methodology,results,and potential causes of differences in these applications of microarrays.Finally,we suggest practices to improve the reliability and reproducibility of microarray experiments.

  4. Acetylsalicylic acid and ascorbic acid combination improves cognition; via antioxidant effect or increased expression of NMDARs and nAChRs?

    Science.gov (United States)

    Kara, Yusuf; Doguc, Duygu Kumbul; Kulac, Esin; Gultekin, Fatih

    2014-05-01

    Chronic inflammation occurs systematically in the central nervous system during ageing, it has been shown that neuroinflammation plays an important role in the pathogenesis of many neurodegenerative disorders. Aspirin, a nonselective COX inhibitor, as well as ascorbic acid, has been purported to protect cerebral tissue. We investigated the effects of subchronic aspirin and ascorbic acid usage on spatial learning, oxidative stress and expressions of NR2A, NR2B, nAChRα7, α4 and β2. Forty male rats (16-18 months) were divided into 4 groups, namely, control, aspirin-treated, ascorbic acid-treated, aspirin+ascorbic acid-treated groups. Following 10-weeks administration period, rats were trained and tested in the Morris water maze. 8-Hydroxy-2-deoxyguanosine and malondialdehyde were evaluated by ELISA and HPLC, respectively. Receptor expressions were assessed by western blotting of hippocampi. Spatial learning performance improved partially in the aspirin group, but significant improvement was seen in the aspirin+ascorbic acid group (p acid group as compared to the control group (p acid in aged rats was shown to enhance cognitive performance and increase the expressions of several receptors related to learning and memory process.

  5. Nordihydroguaiaretic Acid Attenuates the Oxidative Stress-Induced Decrease of CD33 Expression in Human Monocytes

    Directory of Open Access Journals (Sweden)

    Silvia Guzmán-Beltrán

    2013-01-01

    Full Text Available Nordihydroguaiaretic acid (NDGA is a natural lignan with recognized antioxidant and beneficial properties that is isolated from Larrea tridentata. In this study, we evaluated the effect of NDGA on the downregulation of oxidant stress-induced CD33 in human monocytes (MNs. Oxidative stress was induced by iodoacetate (IAA or hydrogen peroxide (H2O2 and was evaluated using reactive oxygen species (ROS production, and cell viability. NDGA attenuates toxicity, ROS production and the oxidative stress-induced decrease of CD33 expression secondary to IAA or H2O2 in human MNs. It was also shown that NDGA (20 μM attenuates cell death in the THP-1 cell line that is caused by treatment with either IAA or H2O2. These results suggest that NDGA has a protective effect on CD33 expression, which is associated with its antioxidant activity in human MNs.

  6. Nordihydroguaiaretic acid attenuates the oxidative stress-induced decrease of CD33 expression in human monocytes.

    Science.gov (United States)

    Guzmán-Beltrán, Silvia; Pedraza-Chaverri, José; Gonzalez-Reyes, Susana; Hernández-Sánchez, Fernando; Juarez-Figueroa, Ulises E; Gonzalez, Yolanda; Bobadilla, Karen; Torres, Martha

    2013-01-01

    Nordihydroguaiaretic acid (NDGA) is a natural lignan with recognized antioxidant and beneficial properties that is isolated from Larrea tridentata. In this study, we evaluated the effect of NDGA on the downregulation of oxidant stress-induced CD33 in human monocytes (MNs). Oxidative stress was induced by iodoacetate (IAA) or hydrogen peroxide (H(2)O(2)) and was evaluated using reactive oxygen species (ROS) production, and cell viability. NDGA attenuates toxicity, ROS production and the oxidative stress-induced decrease of CD33 expression secondary to IAA or H(2)O(2) in human MNs. It was also shown that NDGA (20  μ M) attenuates cell death in the THP-1 cell line that is caused by treatment with either IAA or H(2)O(2). These results suggest that NDGA has a protective effect on CD33 expression, which is associated with its antioxidant activity in human MNs.

  7. UlaR activates expression of the ula operon in Streptococcus pneumoniae in the presence of ascorbic acid

    NARCIS (Netherlands)

    Afzal, Muhammad; Shafeeq, Sulman; Henriques-Normark, Birgitta; Kuipers, Oscar P

    2015-01-01

    In this study, the regulatory mechanism of the ula (utilization of l-ascorbic acid) operon, putatively responsible for transport and utilization of ascorbic acid in Streptococcus pneumoniae strain D39, is studied. β-Galactosidase assay data demonstrate that expression of the ula operon is increased

  8. Expression of the short chain fatty acid receptor GPR41/FFAR3 in autonomic and somatic sensory ganglia

    DEFF Research Database (Denmark)

    Nøhr, Mark Klitgaard; Egerod, K L; Christiansen, S H;

    2015-01-01

    G-protein-coupled receptor 41 (GPR41) also called free fatty acid receptor 3 (FFAR3) is a Gαi-coupled receptor activated by short-chain fatty acids (SCFAs) mainly produced from dietary complex carbohydrate fibers in the large intestine as products of fermentation by microbiota. FFAR3 is expressed...

  9. Retinoic acid receptor agonists regulate expression of ATP-binding cassette transporter G1 in macrophages.

    Science.gov (United States)

    Ayaori, Makoto; Yakushiji, Emi; Ogura, Masatsune; Nakaya, Kazuhiro; Hisada, Tetsuya; Uto-Kondo, Harumi; Takiguchi, Shunichi; Terao, Yoshio; Sasaki, Makoto; Komatsu, Tomohiro; Iizuka, Maki; Yogo, Makiko; Uehara, Yoshinari; Kagechika, Hiroyuki; Nakanishi, Tsuyoshi; Ikewaki, Katsunori

    2012-04-01

    ABC transporter G1 (ABCG1) plays a pivotal role in HDL-mediated cholesterol efflux and atherogenesis. We investigated whether, and how, retinoic acid receptors (RARs) regulate ABCG1 expression in macrophages. All-trans retinoic acid (ATRA), an RAR ligand, increased ABCG1 protein levels and apoA-I/HDL-mediated cholesterol efflux from the macrophages. Both ATRA and other RAR agonists, TTNPB and Am580, increased major transcripts driven by promoter B upstream of exon 5, though minor transcripts driven by promoter A upstream of exon 1 were only increased by ATRA. The stimulatory effects of ATRA on ABCG1 expression were completely abolished in the presence of RAR/RXR antagonists but were only partially canceled in the presence of an LXR antagonist. Adenovirus with overexpressed oxysterol sulfotransferase abolished the LXR pathway, as previously reported, and ATRA-responsiveness in ABCA1/ABCG1 expressions were respectively attenuated by 38 and 22% compared to the control virus. Promoter assays revealed that ABCG1 levels were regulated more by promoter B than promoter A, and ATRA activated promoter B in a liver X receptor-responsive element (LXRE)-dependent manner. Further, LXRE-B in intron 7, but not LXRE-A in intron 5, enhanced ATRA responsiveness under overexpression of all RAR isoforms-RARα/β/γ. In contrast, the activation of promoter B by TTNPB depended on LXRE-B and RARα, but not on RARβ/γ. Finally, chromatin immunoprecipitation and gel-shift assays revealed a specific and direct repeat 4-dependent binding of RARα to LXRE-B. In conclusion, RAR ligands increase ABCA1/G1 expression and apoA-I/HDL-mediated cholesterol efflux from macrophages, and modulate ABCG1 promoter activity via LXRE-dependent mechanisms.

  10. Expression of tropodithietic acid biosynthesis is controlled by a novel autoinducer.

    Science.gov (United States)

    Geng, Haifeng; Belas, Robert

    2010-09-01

    The interactions between marine prokaryotic and eukaryotic microorganisms are crucial to many biological and biogeochemical processes in the oceans. Often the interactions are mutualistic, as in the symbiosis between phytoplankton, e.g., the dinoflagellate Pfiesteria piscicida and Silicibacter sp. TM1040, a member of the Roseobacter taxonomic lineage. It is hypothesized that an important component of this symbiosis is bacterial production of tropodithietic acid (TDA), a biologically active tropolone compound whose synthesis requires the expression of tdaABCDEF (tdaA-F), as well as six additional genes (cysI, malY, paaIJK, and tdaH). The factors controlling tda gene expression are not known, although growth in laboratory standing liquid cultures drastically increases TDA levels. In this report, we measured the transcription of tda genes to gain a greater understanding of the factors controlling their expression. While the expression of tdaAB was constitutive, tdaCDE and tdaF mRNA increased significantly (3.7- and 17.4-fold, respectively) when cells were grown in standing liquid broth compared to their levels with shaking liquid culturing. No transcription of tdaC was detected when a tdaCp::lacZ transcriptional fusion was placed in 11 of the 12 Tda(-) mutant backgrounds, with cysI being the sole exception. The expression of tdaC could be restored to 9 of the remaining 11 Tda(-) mutants-tdaA and tdaH failed to respond-by placing wild-type (Tda(+)) strains in close proximity or by supplying exogenous TDA to the mutant, suggesting that TDA induces tda gene expression. These results indicate that TDA acts as an autoinducer of its own synthesis and suggest that roseobacters may use TDA as a quorum signal.

  11. Expression of Tropodithietic Acid Biosynthesis Is Controlled by a Novel Autoinducer▿ †

    Science.gov (United States)

    Geng, Haifeng; Belas, Robert

    2010-01-01

    The interactions between marine prokaryotic and eukaryotic microorganisms are crucial to many biological and biogeochemical processes in the oceans. Often the interactions are mutualistic, as in the symbiosis between phytoplankton, e.g., the dinoflagellate Pfiesteria piscicida and Silicibacter sp. TM1040, a member of the Roseobacter taxonomic lineage. It is hypothesized that an important component of this symbiosis is bacterial production of tropodithietic acid (TDA), a biologically active tropolone compound whose synthesis requires the expression of tdaABCDEF (tdaA-F), as well as six additional genes (cysI, malY, paaIJK, and tdaH). The factors controlling tda gene expression are not known, although growth in laboratory standing liquid cultures drastically increases TDA levels. In this report, we measured the transcription of tda genes to gain a greater understanding of the factors controlling their expression. While the expression of tdaAB was constitutive, tdaCDE and tdaF mRNA increased significantly (3.7- and 17.4-fold, respectively) when cells were grown in standing liquid broth compared to their levels with shaking liquid culturing. No transcription of tdaC was detected when a tdaCp::lacZ transcriptional fusion was placed in 11 of the 12 Tda− mutant backgrounds, with cysI being the sole exception. The expression of tdaC could be restored to 9 of the remaining 11 Tda− mutants—tdaA and tdaH failed to respond—by placing wild-type (Tda+) strains in close proximity or by supplying exogenous TDA to the mutant, suggesting that TDA induces tda gene expression. These results indicate that TDA acts as an autoinducer of its own synthesis and suggest that roseobacters may use TDA as a quorum signal. PMID:20601479

  12. Correlation of HSP110 expression with all-trans retinoic acid-induced apoptosis.

    Science.gov (United States)

    Evrard, L; Vanmuylder, N; Dourov, N; Hermans, C; Biermans, J; Werry-Huet, A; Rooze, M; Louryan, S

    2000-01-01

    In a previous study, we observed the strong expression of a stress protein of the HSP100/Clp family (HSP110) in apoptotic mesectodermal cells during early mouse facial development. In the present study, we describe the strong expression of the same HSP110 in mesectodermal cells undergoing apoptosis after all-trans retinoic acid (RA) administration. We used a teratological model known to increase cell deaths mainly in the first and second branchial arches during mammalian cephalogenesis: the treatment of E9 mouse embryos with all-trans RA, which results in craniofacial malformations comparable to those that characterize mandibulofacial dysostosis in man. Pregnant NMRI mice were treated with 60 mg/kg body weight of all-trans RA, given orally on day 9 of gestation; embryos were taken 4, 12 or 24 hr after RA administration. The apoptotic pattern of RA-induced cell deaths was confirmed using the dUTP biotin nick-end labeling (TUNEL) method and transmission electron microscopy (TEM). HSP110 expression was detected using an immunohistochemical approach. The increase in the number of TUNEL-positive cells and HSP110-positive cells after all-trans RA administration was quantified in the first branchial arch using a computerized method. Twelve hours after RA administration, the increase in the number of HSP110-positive cells is greater than the increase in the number of TUNEL-positive cells. Twenty-four hours after RA administration, only TUNEL-positive cells remain strong in number. We suggest that HSP110 expression could represent a biochemical event of apoptotic cell death induced by RA, associated with early stages of the apoptotic process. In order to find out if HSP110 expression resulted from neosynthesis, we performed in situ hybridization, which demonstrated that the expression of HSP110 occurred at the level of mRNA.

  13. Polydimethylsiloxane (PDMS) modulates CD38 expression, absorbs retinoic acid and may perturb retinoid signalling.

    Science.gov (United States)

    Futrega, Kathryn; Yu, Jianshi; Jones, Jace W; Kane, Maureen A; Lott, William B; Atkinson, Kerry; Doran, Michael R

    2016-04-21

    Polydimethylsiloxane (PDMS) is the most commonly used material in the manufacture of customized cell culture devices. While there is concern that uncured PDMS oligomers may leach into culture medium and/or hydrophobic molecules may be absorbed into PDMS structures, there is no consensus on how or if PDMS influences cell behaviour. We observed that human umbilical cord blood (CB)-derived CD34(+) cells expanded in standard culture medium on PDMS exhibit reduced CD38 surface expression, relative to cells cultured on tissue culture polystyrene (TCP). All-trans retinoic acid (ATRA) induces CD38 expression, and we reasoned that this hydrophobic molecule might be absorbed by PDMS. Through a series of experiments we demonstrated that ATRA-mediated CD38 expression was attenuated when cultures were maintained on PDMS. Medium pre-incubated on PDMS for extended durations resulted in a time-dependant reduction of ATRA in the medium and increasingly attenuated CD38 expression. This indicated a time-dependent absorption of ATRA into the PDMS. To better understand how PDMS might generally influence cell behaviour, Ingenuity Pathway Analysis (IPA) was used to identify potential upstream regulators. This analysis was performed for differentially expressed genes in primary cells including CD34(+) haematopoietic progenitor cells, mesenchymal stromal cells (MSC), and keratinocytes, and cell lines including prostate cancer epithelial cells (LNCaP), breast cancer epithelial cells (MCF-7), and myeloid leukaemia cells (KG1a). IPA predicted that the most likely common upstream regulator of perturbed pathways was ATRA. We demonstrate here that ATRA is absorbed by PDMS in a time-dependent manner and results in the concomitant reduced expression of CD38 on the cell surface of CB-derived CD34(+) cells.

  14. Expression Profile of Cationic Amino Acid Transporters in Rats with Endotoxin-Induced Uveitis

    Directory of Open Access Journals (Sweden)

    Yung-Ray Hsu

    2016-01-01

    Full Text Available Purpose. The transcellular arginine transportation via cationic amino acid transporter (CAT is the rate-limiting step in nitric oxide (NO synthesis, which is crucial in intraocular inflammation. In this study, CAT isoforms and inducible nitric oxide synthase (iNOS expression was investigated in endotoxin-induced uveitis (EIU. Methods. EIU was induced in Lewis rats by lipopolysaccharide (LPS injection. In the treatment group, the rats were injected intraperitoneally with the proteasome inhibitor bortezomib before EIU induction. After 24 hours, leukocyte quantification, NO measurement of the aqueous humor, and histopathological examination were evaluated. The expression of CAT isoforms and iNOS was determined by reverse transcription-polymerase chain reaction, western blotting, and immunofluorescence staining. Nuclear factor-kappa B (NF-κB binding activity was evaluated by electrophoretic mobility shift assay. The mouse macrophage cell line RAW 264.7 was used to validate the in vivo findings. Results. LPS significantly stimulated iNOS, CAT-2A, and CAT-2B mRNA and protein expression but did not affect CAT-1 in EIU rats and RAW 264.7 cells. Bortezomib attenuated inflammation and inhibited iNOS, CAT-2A, and CAT-2B expression through NF-κB inhibition. Conclusions. CAT-2 and iNOS, but not CAT-1, are specifically involved in EIU. NF-κB is essential in the induction of CAT-2 and iNOS in EIU.

  15. Effect of chronic valproic Acid treatment on hepatic gene expression profile in wfs1 knockout mouse.

    Science.gov (United States)

    Punapart, Marite; Eltermaa, Mall; Oflijan, Julia; Sütt, Silva; Must, Anne; Kõks, Sulev; Schalkwyk, Leonard C; Fernandes, Catherine; Vasar, Eero; Soomets, Ursel; Terasmaa, Anton

    2014-01-01

    Valproic acid (VPA) is a widely used anticonvulsant and mood-stabilizing drug whose use is often associated with drug-induced weight gain. Treatment with VPA has been shown to upregulate Wfs1 expression in vitro. Aim of the present study was to compare the effect of chronic VPA treatment in wild type (WT) and Wfs1 knockout (KO) mice on hepatic gene expression profile. Wild type, Wfs1 heterozygous, and homozygous mice were treated with VPA for three months (300 mg/kg i.p. daily) and gene expression profiles in liver were evaluated using Affymetrix Mouse GeneChip 1.0 ST array. We identified 42 genes affected by Wfs1 genotype, 10 genes regulated by VPA treatment, and 9 genes whose regulation by VPA was dependent on genotype. Among the genes that were regulated differentially by VPA depending on genotype was peroxisome proliferator-activated receptor delta (Ppard), whose expression was upregulated in response to VPA treatment in WT, but not in Wfs1 KO mice. Thus, regulation of Ppard by VPA is dependent on Wfs1 genotype.

  16. Regulation of basal and oxidative stress-triggered jasmonic acid-related gene expression by glutathione.

    Science.gov (United States)

    Han, Yi; Mhamdi, Amna; Chaouch, Sejir; Noctor, Graham

    2013-06-01

    Glutathione is a determinant of cellular redox state with roles in defence and detoxification. Emerging concepts suggest that this compound also has functions in cellular signalling. Here, we report evidence that glutathione plays potentially important roles in setting signalling strength through the jasmonic acid (JA) pathway. Firstly, we show that basal expression of JA-related genes is correlated with leaf glutathione content when the latter is manipulated either genetically or pharmacologically. Secondly, analyses of an oxidative stress signalling mutant, cat2, reveal that up-regulation of the JA pathway triggered by intracellular oxidation requires accompanying glutathione accumulation. Genetically blocking this accumulation in a cat2 cad2 line largely annuls H2 O2 -induced expression of JA-linked genes, and this effect can be rescued by exogenously supplying glutathione. While most attention on glutathione functions in biotic stress responses has been focused on the thiol-regulated protein NPR1, a comparison of JA-linked gene expression in cat2 cad2 and cat2 npr1 double mutants provides evidence that glutathione acts through other components to regulate the response of this pathway to oxidative stress. Our study provides new information implicating glutathione as a factor determining basal JA gene expression and suggests novel glutathione-dependent control points that regulate JA signalling in response to intracellular oxidation.

  17. Multivalent display of quinic acid based ligands for targeting E-selectin expressing cells.

    Science.gov (United States)

    Shamay, Yosi; Paulin, Denise; Ashkenasy, Gonen; David, Ayelet

    2009-10-08

    The site-specific expression of molecular markers on endothelial cells of blood vessels during inflammatory response and angiogenesis provides an opportunity to target drugs and imaging molecules to the vascular endothelium of diseased tissues. This paper describes an innovative strategy for selective delivery of polymer conjugates to E- and P-selectin expressing cells using a series of quinic acid (Qa) based non-carbohydrate analogues of the natural ligand sialyl Lewis(x) (sLe(x)) as targeting moieties. We demonstrate that such analogues antagonize the adhesion of sLe(x) expressing HL-60 cells to both E- and P-selectin. Significantly, the apparent avidity of polymer conjugates carrying multiple Qa copies has increased by 3 orders of magnitude relative to their monomeric forms. Furthermore, we found that the major mechanism of copolymer entry and delivery into E-selectin expressing cells is endocytosis. These selectin-targetable copolymers provide the foundation to support controlled delivery of anticancer drugs and imaging agents to tumor vasculature for therapeutic and diagnostic applications.

  18. Expression of the cathelicidin LL-37 is modulated by short chain fatty acids in colonocytes: relevance of signalling pathways

    OpenAIRE

    Schauber, J; Svanholm, C; Termén, S; Iffland, K; Menzel, T.; Scheppach, W; Melcher, R.; Agerberth, B.; Lührs, H.; G. H. Gudmundsson

    2003-01-01

    Background and aims: Short chain fatty acids (SCFA) exert profound effects on the colonic mucosa. In particular, SCFA modulate mucosal immune functions. The antimicrobial cathelicidin LL-37 is expressed by colon epithelial cells. In the present study the effect of SCFA on LL-37 expression was investigated.

  19. Alteration of gene expression in mammary gland tissue of dairy cows in response to dietary unsaturated fatty acids

    NARCIS (Netherlands)

    Mach Casellas, N.; Jacobs, A.A.A.; Kruijt, L.; Baal, van J.; Smits, M.C.J.

    2014-01-01

    The aim of this study was to determine the effects of unprotected dietary unsaturated fatty acids (UFA) from different plant oils on gene expression in the mammary gland of grazing dairy cows. Milk composition and gene expression in the mammary gland tissue were evaluated in grazing dairy cows suppl

  20. Differential Display of Cotton cDNAs Expressed by Salicylic Acid Induction

    Institute of Scientific and Technical Information of China (English)

    李骥; 赵广荣; 刘进元

    2003-01-01

    Salicylic acid (SA) is very important in systemic acquired resistance and hypersensitive response in plant defense, and yet its role is not fully understood.This study seeks to clarify the mechanism of SA induced resistance in cotton.Total RNA was extracted from low-gossypol cultivated cotton seedlings treated with exogenous SA and subjected to fluorescent differential display-PCR (FDD-PCR).Seven cDNA fragments were selected from the total ten differential bands.Comparison with Genbank database shows that all seven cDNA sequences are newly discovered in cotton.However, they share high amino acid identity to some registered cDNAs.Among them, three of the cDNAs could be predicted to encode basic chitinase, penicillin-binding 6 b precursor and ATP-dependent DNA helicase RecG, while the functions of the other four cDNAs are undetermined.Dot blot analysis demonstrates that the expression of five cDNAs in cotton seedlings is induced by SA, while SA induction has a negative effect on the transcript accumulation of the other two cDNAs (E13 and E14).Since SA was previously shown to enhance the resistance to cotton wilt disease, the finding of a basic chitinase gene in cotton expressed by SA induction will provide a new insight into induced disease resistance in cotton.

  1. Disrupting protein expression with Peptide Nucleic Acids reduces infection by obligate intracellular Rickettsia.

    Directory of Open Access Journals (Sweden)

    Rebecca S Pelc

    Full Text Available Peptide Nucleic Acids (PNAs are single-stranded synthetic nucleic acids with a pseudopeptide backbone in lieu of the phosphodiester linked sugar and phosphate found in traditional oligos. PNA designed complementary to the bacterial Shine-Dalgarno or start codon regions of mRNA disrupts translation resulting in the transient reduction in protein expression. This study examines the use of PNA technology to interrupt protein expression in obligate intracellular Rickettsia sp. Their historically intractable genetic system limits characterization of protein function. We designed PNA targeting mRNA for rOmpB from Rickettsia typhi and rickA from Rickettsia montanensis, ubiquitous factors important for infection. Using an in vitro translation system and competitive binding assays, we determined that our PNAs bind target regions. Electroporation of R. typhi and R. montanensis with PNA specific to rOmpB and rickA, respectively, reduced the bacteria's ability to infect host cells. These studies open the possibility of using PNA to suppress protein synthesis in obligate intracellular bacteria.

  2. Disrupting protein expression with Peptide Nucleic Acids reduces infection by obligate intracellular Rickettsia.

    Science.gov (United States)

    Pelc, Rebecca S; McClure, Jennifer C; Kaur, Simran J; Sears, Khandra T; Rahman, M Sayeedur; Ceraul, Shane M

    2015-01-01

    Peptide Nucleic Acids (PNAs) are single-stranded synthetic nucleic acids with a pseudopeptide backbone in lieu of the phosphodiester linked sugar and phosphate found in traditional oligos. PNA designed complementary to the bacterial Shine-Dalgarno or start codon regions of mRNA disrupts translation resulting in the transient reduction in protein expression. This study examines the use of PNA technology to interrupt protein expression in obligate intracellular Rickettsia sp. Their historically intractable genetic system limits characterization of protein function. We designed PNA targeting mRNA for rOmpB from Rickettsia typhi and rickA from Rickettsia montanensis, ubiquitous factors important for infection. Using an in vitro translation system and competitive binding assays, we determined that our PNAs bind target regions. Electroporation of R. typhi and R. montanensis with PNA specific to rOmpB and rickA, respectively, reduced the bacteria's ability to infect host cells. These studies open the possibility of using PNA to suppress protein synthesis in obligate intracellular bacteria.

  3. Glucocorticoids modulate the response of ornithine decarboxylase to unilateral removal of the dorsal hippocampus

    NARCIS (Netherlands)

    De Kloet, E R; Cousin, M A; Veldhuis, H D; Voorhuis, T D; Lando, D

    1983-01-01

    The effect of unilateral removal of the dorsal hippocampus and of glucocorticoid administration was measured on the activity of ornithine decarboxylase (ODC) in the remaining contralateral hippocampus lobe. Unilateral hippocampectomy (Hx) resulted in a rapid rise of ODC activity in the contralateral

  4. Evidence for the existence of mammalian acetoacetate decarboxylase: with special reference to human blood serum

    NARCIS (Netherlands)

    Stekelenburg, Gerard J. van; Koorevaar, Gerrit

    1972-01-01

    In this article evidence is presented for the existence of mammalian acetoacetate decarboxylase (acetoacetate carboxy-lyase: E.G. 4.1.1.4). From experiments with human blood serum the presence of a non-ultrafiltrable activator, accelerating the decomposition of acetoacetate into acetone and carbon d

  5. Increased fatty acid synthase expression in prostate biopsy cores predicts higher Gleason score in radical prostatectomy specimen

    OpenAIRE

    HAMADA, SHINSUKE; Horiguchi, Akio; Kuroda, Kenji; Ito, Keiichi; ASANO, TOMOHIKO; Miyai, Kosuke; Iwaya, Keiichi

    2014-01-01

    Background Fatty acid synthase (FAS) is highly expressed in various types of cancer, and elevated expression of FAS has been suggested to be a predictor of tumor aggressiveness and poor prognosis. We examined whether FAS expression in prostate biopsy cores could predict the pathological characteristics of radical prostatectomy (RP) specimens. Methods Paraffin-embedded prostate biopsy cores, obtained from 102 patients who subsequently underwent RP, were immunostained with polyclonal anti-FAS a...

  6. Production of 13S-hydroxy-9(Z)-octadecenoic acid from linoleic acid by whole recombinant cells expressing linoleate 13-hydratase from Lactobacillus acidophilus.

    Science.gov (United States)

    Park, Ji-Young; Lee, Seon-Hwa; Kim, Kyoung-Rok; Park, Jin-Byung; Oh, Deok-Kun

    2015-08-20

    Linoleate 13-hydratase from Lactobacillus acidophilus LMG 11470 converted linoleic acid to hydroxyl fatty acid, which was identified as 13S-hydroxy-9(Z)-octadecenoic acid (13-HOD) by GC-MS and NMR. The expression of linoleate 13-hydratase gene in Escherichia coli was maximized by using pACYC plasmid and super optimal broth with catabolite repression (SOC) medium containing 40mM Mg(2+). To optimize induction conditions, recombinant cells were cultivated at 37°C, 1mM isopropyl-β-d-thiogalactopyranoside was added at 2h, and the culture was further incubated at 16°C for 18h. Recombinant cells expressing linoleate 13-hydratase from L. acidophilus were obtained under the optimized expression conditions and used for 13-HOD production from linoleic acid. The optimal reaction conditions were pH 6.0, 40°C, 0.25% (v/v) Tween 40, 25gl(-1) cells, and 100gl(-1) linoleic acid, and under these conditions, whole recombinant cells produced 79gl(-1) 13-HOD for 3h with a conversion yield of 79% (w/w), a volumetric productivity of 26.3gl(-1)h(-1), and a specific productivity of 1.05g g-cells(-1)h(-1). To the best of our knowledge, the recombinant cells produced hydroxy fatty acid with the highest concentration and productivity reported so far.

  7. Analysis of the porcine APOA2 gene expression in liver, polymorphism identification and association with fatty acid composition traits.

    Science.gov (United States)

    Ballester, M; Revilla, M; Puig-Oliveras, A; Marchesi, J A P; Castelló, A; Corominas, J; Fernández, A I; Folch, J M

    2016-10-01

    APOA2 is a protein implicated in triglyceride, fatty acid and glucose metabolism. In pigs, the APOA2 gene is located on pig chromosome 4 (SSC4) in a QTL region affecting fatty acid composition, fatness and growth traits. In this study, we evaluated APOA2 as a candidate gene for meat quality traits in an Iberian × Landrace backcross population. The APOA2:c.131T>A polymorphism, located in exon 3 of APOA2 and determining a missense mutation, was associated with the percentage of hexadecenoic acid [C16:1(n-9)], linoleic acid [C18:2(n-6)], α-linolenic acid [C18:3(n-3)], dihomo-gamma-linolenic acid [C20:3(n-6)] and polyunsaturated fatty acids (PUFAs) in backfat. Furthermore, this SNP was associated with the global mRNA expression levels of APOA2 in liver and was used as a marker to determine allelic expression imbalance by pyrosequencing. We determined an overexpression of the T allele in heterozygous samples with a mean ratio of 2.8 (T/A), observing a high variability in the allelic expression among individuals. This result suggests that complex regulatory mechanisms, beyond a single polymorphism (e.g. epigenetic effects or multiple cis-acting polymorphisms), may be regulating APOA2 gene expression.

  8. Expression, purification and crystallization of class C acid phosphatases from Francisella tularensis and Pasteurella multocida

    Science.gov (United States)

    Singh, Harkewal; Felts, Richard L.; Ma, Li; Malinski, Thomas J.; Calcutt, Michael J.; Reilly, Thomas J.; Tanner, John J.

    2009-01-01

    Class C nonspecific acid phosphatases are bacterial enzymes that are secreted across the cytoplasmic membrane and hydrolyze a variety of phosphomono­esters at acidic pH. These enzymes are of interest for the development of improved vaccines and clinical diagnostic methods. In one case, the category A pathogen Francisella tularensis, the class C phosphatase plays a role in bacterial fitness. Here, the cloning, expression, purification and crystallization methods for the class C acid phosphatases from F. tularensis and Pasteurella multocida are reported. Crystals of the F. tularensis enzyme diffracted to 2.0 Å resolution and belonged to space group C2221, with one enzyme molecule in the asymmetric unit. Crystals of the P. multocida enzyme diffracted to 1.85 Å resolution and belonged to space group C2, with three molecules in the asymmetric unit. Diffraction patterns from crystals of the P. multocida enzyme exhibited multiple interpenetrating reciprocal-space lattices, indicating epitaxial twinning. Despite this aberrance, autoindexing was robust and the data could be satisfactorily processed to 1.85 Å resolution using MOSFLM and SCALA. PMID:19255471

  9. Fatty acid esters of phloridzin induce apoptosis of human liver cancer cells through altered gene expression.

    Directory of Open Access Journals (Sweden)

    Sandhya V G Nair

    Full Text Available Phloridzin (phlorizin or phloretin 2'-O-glucoside is known for blocking intestinal glucose absorption. We have investigated the anticarcinogenic effect of phloridzin and its novel derivatives using human cancer cell lines. We have synthesised novel acylated derivatives of phloridzin with six different long chain fatty acids by regioselective enzymatic acylation using Candida Antarctica lipase B. The antiproliferative effects of the new compounds were investigated in comparison with the parent compounds, phloridzin, aglycone phloretin, the six free fatty acids and chemotherapeutic drugs (sorafenib, doxorubicin and daunorubicin using human hepatocellular carcinoma HepG2 cells, human breast adenocarcinoma MDA-MB-231 cells and acute monocytic leukemia THP-1 cells along with normal human and rat hepatocytes. The fatty acid esters of phloridzin inhibited significantly the growth of the two carcinoma and leukemia cells while similar treatment doses were not toxic to normal human or rat hepatocytes. The antiproliferative potency of fatty esters of phloridzin was comparable to the potency of the chemotherapeutic drugs. The fatty acid esters of phloridzin inhibited DNA topoisomerases IIα activity that might induce G0/G1 phase arrest, induced apoptosis via activation of caspase-3, and decreased ATP level and mitochondrial membrane potential in HepG2 cells. Based on the high selectivity on cancer cells, decosahexaenoic acid (DHA ester of phloridzin was selected for gene expression analysis using RT2PCR human cancer drug target array. Antiproliferative effect of DHA ester of phloridzin could be related to the down regulation of anti-apoptotic gene (BCL2, growth factor receptors (EBFR family, IGF1R/IGF2, PDGFR and its downstream signalling partners (PI3k/AKT/mTOR, Ras/Raf/MAPK, cell cycle machinery (CDKs, TERT, TOP2A, TOP2B as well as epigenetics regulators (HDACs. These results suggest that fatty esters of phloridzin have potential chemotherapeutic effects

  10. RETINOIC ACID DOWN-REGULATES BONE MORPHOGENETIC PROTEIN 7 EXPRESSION IN RAT WITH CLEFT PALATE

    Institute of Scientific and Technical Information of China (English)

    Lei Guo; Yu-yan Zhao; Shi-liang Zhang; Kui Liu; Xiao-yu Gao

    2008-01-01

    Objective To evaluate the effects of retinoic acid (RA) on expression of bone morphogenetic protein 7 (BMP-7)in rat fetus with cleft palate, and the effects of RA on proliferation and apoptosis of osteoblasts. Methods All-trans RA (ATRA) was used to induce congenital cleft palate in Wistar rat. BMP-7 mRNA expres-sion in maxillary bone tissue of fetal rats was measured by Northern blotting analysis. Flow cytometry and MTT assay were used to measure the apoptosis and proliferation of ATRA-treated MC-3T3-E1 cells. BMP-7 mRNA and protein ex-pressions in ATRA-treated MC-3T3-E1 cells were detected by RT-PCR and Western blotting analysis.Results ATRA could induce cleft palate of rat fetus. The incidence rate of cleft palate induced by 100 mg/kg AT-RA (45.5%) was significantly higher than 50 mg/kg ATRA (12.5%, P<0.05). BMP-7 mRNA expression de-creased in maxillary bone tissue of rat fetus with cleft palate. MC-3T3-E1 cells proliferation treated with 1 × 10-6 mol/L ATRA decreased by 60%, the cell apoptosis increased by 2 times. BMP-7 mR.NA and protein levels in MC-3T3-E1cells treated with 1 × 10-6 mol/L ATRA decreased by 60% and 80%, respectively, compared with ATRA-untreated ceils (P<0.05).Conclusions BMP-7 may play an important role in embryonic palate development RA may possess the ability to down-regulate cell proliferation through regulation of BMP-7 gene expression.

  11. Nucleic and amino acid sequences relating to a novel transketolase, and methods for the expression thereof

    Energy Technology Data Exchange (ETDEWEB)

    Croteau, Rodney Bruce (Pullman, WA); Wildung, Mark Raymond (Colfax, WA); Lange, Bernd Markus (Pullman, WA); McCaskill, David G. (Pullman, WA)

    2001-01-01

    cDNAs encoding 1-deoxyxylulose-5-phosphate synthase from peppermint (Mentha piperita) have been isolated and sequenced, and the corresponding amino acid sequences have been determined. Accordingly, isolated DNA sequences (SEQ ID NO:3, SEQ ID NO:5, SEQ ID NO:7) are provided which code for the expression of 1-deoxyxylulose-5-phosphate synthase from plants. In another aspect the present invention provides for isolated, recombinant DXPS proteins, such as the proteins having the sequences set forth in SEQ ID NO:4, SEQ ID NO:6 and SEQ ID NO:8. In other aspects, replicable recombinant cloning vehicles are provided which code for plant 1-deoxyxylulose-5-phosphate synthases, or for a base sequence sufficiently complementary to at least a portion of 1-deoxyxylulose-5-phosphate synthase DNA or RNA to enable hybridization therewith. In yet other aspects, modified host cells are provided that have been transformed, transfected, infected and/or injected with a recombinant cloning vehicle and/or DNA sequence encoding a plant 1-deoxyxylulose-5-phosphate synthase. Thus, systems and methods are provided for the recombinant expression of the aforementioned recombinant 1-deoxyxylulose-5-phosphate synthase that may be used to facilitate its production, isolation and purification in significant amounts. Recombinant 1-deoxyxylulose-5-phosphate synthase may be used to obtain expression or enhanced expression of 1-deoxyxylulose-5-phosphate synthase in plants in order to enhance the production of 1-deoxyxylulose-5-phosphate, or its derivatives such as isopentenyl diphosphate (BP), or may be otherwise employed for the regulation or expression of 1-deoxyxylulose-5-phosphate synthase, or the production of its products.

  12. Altered Expression Pattern of Acid-Sensing Ion Channel Isoforms in Piriform Cortex After Seizures.

    Science.gov (United States)

    Wu, Hao; Wang, Chao; Liu, Bei; Li, Huanfa; Zhang, Yu; Dong, Shan; Gao, Guodong; Zhang, Hua

    2016-04-01

    The piriform cortex (PC) is highly susceptible to chemical and electrical seizure induction. Epileptiform activity is associated with an acid shift in extracellular pH, suggesting that acid-sensing ion channels (ASICs) expressed by PC neurons may contribute to this enhanced epileptogenic potential. In epileptic rats and surgical samples from patients with medial temporal lobe epilepsy (TLE), PC layer II ASIC1a-immunopositive neurons appeared swollen with dendritic elongation, and there was loss of ASIC1a-positive neurons in layer III, consistent with enhanced vulnerability to TLE-induced plasticity and cell death. In rats, pilocarpine-induced seizures led to transient downregulation of ASIC1a and concomitant upregulation of ASIC2a in the first few days post-seizure. These changes in expression may be due to seizure-induced oxidative stress as a similar reciprocal change in ASIC1a, and ASIC2a expression was observed in PC12 cells following H2O2 application. The proportion of ASIC1a/ASIC2a heteromers was reduced in the acute phase following status epilepticus (SE) but increased during the latent phase when rats developed spontaneous seizures. Knockdown of ASIC2a by RNAi reduced dendritic length and spine density in primary neurons, suggesting that seizure-induced upregulation of ASIC2a contributes to dendritic lengthening in PC layer II in rats. Administration of the ASIC inhibitor amiloride before pilocarpine reduced the proportion of rats reaching Racine level IV seizures, protected layer II and III neurons, and prolonged survival in the acute phase following SE. Our findings suggest that ASICs may enhance susceptibility to epileptogenesis in the PC. Inhibition of ASICs, particularly ASIC2a, may suppress seizures originating in the PC.

  13. Rho Kinase ROCK2 Mediates Acid-Induced NADPH Oxidase NOX5-S Expression in Human Esophageal Adenocarcinoma Cells.

    Directory of Open Access Journals (Sweden)

    Jie Hong

    Full Text Available Mechanisms of the progression from Barrett's esophagus (BE to esophageal adenocarcinoma (EA are not fully understood. We have shown that NOX5-S may be involved in this progression. However, how acid upregulates NOX5-S is not well known. We found that acid-induced increase in NOX5-S expression was significantly decreased by the Rho kinase (ROCK inhibitor Y27632 in BE mucosal biopsies and FLO-1 EA cells. In addition, acid treatment significantly increased the Rho kinase activity in FLO-1 cells. The acid-induced increase in NOX5-S expression and H2O2 production was significantly decreased by knockdown of Rho kinase ROCK2, but not by knockdown of ROCK1. Conversely, the overexpression of the constitutively active ROCK2, but not the constitutively active ROCK1, significantly enhanced the NOX5-S expression and H2O2 production. Moreover, the acid-induced increase in Rho kinase activity and in NOX5-S mRNA expression was blocked by the removal of calcium in both FLO-1 and OE33 cells. The calcium ionophore A23187 significantly increased the Rho kinase activity and NOX5-S mRNA expression. We conclude that acid-induced increase in NOX5-S expression and H2O2 production may depend on the activation of ROCK2, but not ROCK1, in EA cells. The acid-induced activation of Rho kinase may be mediated by the intracellular calcium increase. It is possible that persistent acid reflux present in BE patients may increase the intracellular calcium, activate ROCK2 and thereby upregulate NOX5-S. High levels of reactive oxygen species derived from NOX5-S may cause DNA damage and thereby contribute to the progression from BE to EA.

  14. Rho Kinase ROCK2 Mediates Acid-Induced NADPH Oxidase NOX5-S Expression in Human Esophageal Adenocarcinoma Cells.

    Science.gov (United States)

    Hong, Jie; Li, Dan; Cao, Weibiao

    2016-01-01

    Mechanisms of the progression from Barrett's esophagus (BE) to esophageal adenocarcinoma (EA) are not fully understood. We have shown that NOX5-S may be involved in this progression. However, how acid upregulates NOX5-S is not well known. We found that acid-induced increase in NOX5-S expression was significantly decreased by the Rho kinase (ROCK) inhibitor Y27632 in BE mucosal biopsies and FLO-1 EA cells. In addition, acid treatment significantly increased the Rho kinase activity in FLO-1 cells. The acid-induced increase in NOX5-S expression and H2O2 production was significantly decreased by knockdown of Rho kinase ROCK2, but not by knockdown of ROCK1. Conversely, the overexpression of the constitutively active ROCK2, but not the constitutively active ROCK1, significantly enhanced the NOX5-S expression and H2O2 production. Moreover, the acid-induced increase in Rho kinase activity and in NOX5-S mRNA expression was blocked by the removal of calcium in both FLO-1 and OE33 cells. The calcium ionophore A23187 significantly increased the Rho kinase activity and NOX5-S mRNA expression. We conclude that acid-induced increase in NOX5-S expression and H2O2 production may depend on the activation of ROCK2, but not ROCK1, in EA cells. The acid-induced activation of Rho kinase may be mediated by the intracellular calcium increase. It is possible that persistent acid reflux present in BE patients may increase the intracellular calcium, activate ROCK2 and thereby upregulate NOX5-S. High levels of reactive oxygen species derived from NOX5-S may cause DNA damage and thereby contribute to the progression from BE to EA.

  15. Uteroplacental insufficiency down regulates insulin receptor and affects expression of key enzymes of long-chain fatty acid (LCFA metabolism in skeletal muscle at birth

    Directory of Open Access Journals (Sweden)

    Puglianiello Antonella

    2008-05-01

    Full Text Available Abstract Background Epidemiological studies have revealed a relationship between early growth restriction and the subsequent development of insulin resistance and type 2 diabetes. Ligation of the uterine arteries in rats mimics uteroplacental insufficiency and serves as a model of intrauterine growth restriction (IUGR and subsequent developmental programming of impaired glucose tolerance, hyperinsulinemia and adiposity in the offspring. The objective of this study was to investigate the effects of uterine artery ligation on the skeletal muscle expression of insulin receptor and key enzymes of LCFA metabolism. Methods Bilateral uterine artery ligation was performed on day 19 of gestation in Sprague-Dawley pregnant rats. Muscle of the posterior limb was dissected at birth and processed by real-time RT-PCR to analyze the expression of insulin receptor, ACCα, ACCβ (acetyl-CoA carboxylase alpha and beta subunits, ACS (acyl-CoA synthase, AMPK (AMP-activated protein kinase, alpha2 catalytic subunit, CPT1B (carnitine palmitoyltransferase-1 beta subunit, MCD (malonyl-CoA decarboxylase in 14 sham and 8 IUGR pups. Muscle tissue was treated with lysis buffer and Western immunoblotting was performed to assay the protein content of insulin receptor and ACC. Results A significant down regulation of insulin receptor protein (p Conclusion Our data suggest that uteroplacental insufficiency may affect skeletal muscle metabolism down regulating insulin receptor and reducing the expression of key enzymes involved in LCFA formation and oxidation.

  16. Teneligliptin Decreases Uric Acid Levels by Reducing Xanthine Dehydrogenase Expression in White Adipose Tissue of Male Wistar Rats

    Directory of Open Access Journals (Sweden)

    Chihiro Moriya

    2016-01-01

    Full Text Available We investigated the effects of teneligliptin on uric acid metabolism in male Wistar rats and 3T3-L1 adipocytes. The rats were fed with a normal chow diet (NCD or a 60% high-fat diet (HFD with or without teneligliptin for 4 weeks. The plasma uric acid level was not significantly different between the control and teneligliptin groups under the NCD condition. However, the plasma uric acid level was significantly decreased in the HFD-fed teneligliptin treated rats compared to the HFD-fed control rats. The expression levels of xanthine dehydrogenase (Xdh mRNA in liver and epididymal adipose tissue of NCD-fed rats were not altered by teneligliptin treatment. On the other hand, Xdh expression was reduced significantly in the epididymal adipose tissue of the HFD-fed teneligliptin treated rats compared with that of HFD-fed control rats, whereas Xdh expression in liver did not change significantly in either group. Furthermore, teneligliptin significantly decreased Xdh expression in 3T3-L1 adipocytes. DPP-4 treatment significantly increased Xdh expression in 3T3-L1 adipocytes. With DPP-4 pretreatment, teneligliptin significantly decreased Xdh mRNA expression compared to the DPP-4-treated 3T3-L1 adipocytes. In conclusion, our studies suggest that teneligliptin reduces uric acid levels by suppressing Xdh expression in epididymal adipose tissue of obese subjects.

  17. A phosphorylation defective retinoic acid receptor mutant mimics the effects of retinoic acid on EGFR mediated AP-1 expression and cancer cell proliferation

    Directory of Open Access Journals (Sweden)

    Kim Randie

    2002-10-01

    Full Text Available Abstract Background The effects of the vitamin A metabolite retinoic acid (RA are mediated at the transcriptional level by retinoic acid receptors (RAR. These proteins are part of a superfamily of transcription factors which activate target gene expression when bound to their respective ligands. In addition to ligand binding, heterodimerization with transcriptional cofactors and posttranslational modification such as phosphorylation are also critical for transactivation function. Previous studies have shown that phosphorylation of a serine residue at amino acid 77 in the RARα amino terminus was required for basal activation function of the transcription factor. Results We have determined that RA inhibits cyclin H and cdk7 expression thereby decreasing levels of phosphorylated RARα in human cancer cell lines. To determine the effects of decreased RARα phosphorylation in human cancer cells, we stably transfected a phosphorylation defective mutant RARα expression construct into SCC25 cultures. Cells expressing the mutant RARα proliferated more slowly than control clones. This decreased proliferation was associated with increased cyclin dependent kinase inhibitor expression and decreased S phase entry. In the absence of ligand, the RARα mutant inhibited AP-1 activity to an extent similar to that of RA treated control clones. Levels of some AP-1 proteins were inhibited due to decreased EGFR expression upstream in the signaling pathway. Conclusions These results indicate that hypophosphorylated RARα can mimic the anti-AP-1 effects of RA in the absence of ligand.

  18. Gene expression changes associated with Barrett's esophagus and Barrett's-associated adenocarcinoma cell lines after acid or bile salt exposure

    Directory of Open Access Journals (Sweden)

    Sahbaie Peyman

    2007-06-01

    Full Text Available Abstract Background Esophageal reflux and Barrett's esophagus represent two major risk factors for the development of esophageal adenocarcinoma. Previous studies have shown that brief exposure of the Barrett's-associated adenocarcinoma cell line, SEG-1, or primary cultures of Barrett's esophageal tissues to acid or bile results in changes consistent with cell proliferation. In this study, we determined whether similar exposure to acid or bile salts results in gene expression changes that provide insights into malignant transformation. Methods Using previously published methods, Barrett's-associated esophageal adenocarcinoma cell lines and primary cultures of Barrett's esophageal tissue were exposed to short pulses of acid or bile salts followed by incubation in culture media at pH 7.4. A genome-wide assessment of gene expression was then determined for the samples using cDNA microarrays. Subsequent analysis evaluated for statistical differences in gene expression with and without treatment. Results The SEG-1 cell line showed changes in gene expression that was dependent on the length of exposure to pH 3.5. Further analysis using the Gene Ontology, however, showed that representation by genes associated with cell proliferation is not enhanced by acid exposure. The changes in gene expression also did not involve genes known to be differentially expressed in esophageal adenocarcinoma. Similar experiments using short-term primary cultures of Barrett's esophagus also did not result in detectable changes in gene expression with either acid or bile salt exposure. Conclusion Short-term exposure of esophageal adenocarcinoma SEG-1 cells or primary cultures of Barrett's esophagus does not result in gene expression changes that are consistent with enhanced cell proliferation. Thus other model systems are needed that may reflect the impact of acid and bile salt exposure on the esophagus in vivo.

  19. Influence of Different Levels of Lipoic Acid Synthase Gene Expression on Diabetic Nephropathy

    Science.gov (United States)

    Xu, Longquan; Hiller, Sylvia; Simington, Stephen; Nickeleit, Volker; Maeda, Nobuyo; James, Leighton R.; Yi, Xianwen

    2016-01-01

    Oxidative stress is implicated in the pathogenesis of diabetic nephropathy (DN) but outcomes of many clinical trials are controversial. To define the role of antioxidants in kidney protection during the development of diabetic nephropathy, we have generated a novel genetic antioxidant mouse model with over- or under-expression of lipoic acid synthase gene (Lias). These models have been mated with Ins2Akita/+ mice, a type I diabetic mouse model. We compare the major pathologic changes and oxidative stress status in two new strains of the mice with controls. Our results show that Ins2Akita/+ mice with under-expressed Lias gene, exhibit higher oxidative stress and more severe DN features (albuminuria, glomerular basement membrane thickening and mesangial matrix expansion). In contrast, Ins2Akita/+ mice with highly-expressed Lias gene display lower oxidative stress and less DN pathologic changes. Our study demonstrates that strengthening endogenous antioxidant capacity could be an effective strategy for prevention and treatment of DN. PMID:27706190

  20. Glial fibrillary acidic protein isoform expression in plaque related astrogliosis in Alzheimer's disease.

    Science.gov (United States)

    Kamphuis, Willem; Middeldorp, Jinte; Kooijman, Lieneke; Sluijs, Jacqueline A; Kooi, Evert-Jan; Moeton, Martina; Freriks, Michel; Mizee, Mark R; Hol, Elly M

    2014-03-01

    In Alzheimer's disease (AD), amyloid plaques are surrounded by reactive astrocytes with an increased expression of intermediate filaments including glial fibrillary acidic protein (GFAP). Different GFAP isoforms have been identified that are differentially expressed by specific subpopulations of astrocytes and that impose different properties to the intermediate filament network. We studied transcript levels and protein expression patterns of all known GFAP isoforms in human hippocampal AD tissue at different stages of the disease. Ten different transcripts for GFAP isoforms were detected at different abundancies. Transcript levels of most isoforms increased with AD progression. GFAPδ-immunopositive astrocytes were observed in subgranular zone, hilus, and stratum-lacunosum-moleculare. GFAPδ-positive cells also stained for GFAPα. In AD donors, astrocytes near plaques displayed increased staining of both GFAPα and GFAPδ. The reading-frame-shifted isoform, GFAP(+1), staining was confined to a subset of astrocytes with long processes, and their number increased in the course of AD. In conclusion, the various GFAP isoforms show differential transcript levels and are upregulated in a concerted manner in AD. The GFAP(+1) isoform defines a unique subset of astrocytes, with numbers increasing with AD progression. These data indicate the need for future exploration of underlying mechanisms concerning the functions of GFAPδ and GFAP(+1) isoforms in astrocytes and their possible role in AD pathology.

  1. Inhibition of matrix metalloproteinases expression in human dental pulp cells by all-trans retinoic acid

    Institute of Scientific and Technical Information of China (English)

    Jin Man Kim; Sang Wook Kang; Su-Mi Shin; Duck Su Kim; Kyong-Kyu Choi; Eun-Cheol Kim; Sun-Young Kim

    2014-01-01

    All-trans retinoic acid (ATRA) inhibits matrix metalloproteinase (MMP)-2 and MMP-9 in synovial fibroblasts, skin fibroblasts, bronchoalveolar lavage cells and cancer cells, but activates MMP-9 in neuroblast and leukemia cells. Very little is known regarding whether ATRA can activate or inhibit MMPs in human dental pulp cells (HDPCs). The purpose of this study was to determine the effects of ATRA on the production and secretion of MMP-2 and-9 in HDPCs. The productions and messenger RNA (mRNA) expressions of MMP-2 and-9 were accessed by gelatin zymography and real-time polymerase chain reaction (PCR), respectively. ATRA was found to decrease MMP-2 level in a dose-dependent manner. Significant reduction in MMP-2 mRNA expression was also observed in HDPCs treated with 25 mmol?L21 ATRA. However, HDPCs treated with ATRA had no effect on the pattern of MMP-9 produced or secreted in either cell extracts or conditioned medium fractions. Taken together, ATRA had an inhibitory effect on MMP-2 expression in HDPCs, which suggests that ATRA could be a candidate as a medicament which could control the inflammation of pulp tissue in vital pulp therapy and regenerative endodontics.

  2. Protein and Amino Acid Supplementation Does Not Alter Proteolytic Gene Expression following Immobilization

    Directory of Open Access Journals (Sweden)

    Jennifer A. Bunn

    2011-01-01

    Full Text Available Objective. To determine if supplementation of protein and amino acids (PAA decreases skeletal muscle expression of atrophy-related genes, muscle mass, and strength during immobilization in humans. Methods. Twenty males wore a lower-limb immobilization boot for 28 days and consumed either a PAA supplement (28 g protein or carbohydrate placebo (28 g maltodextrose, while consuming their normal daily diet. Testing sessions included dietary analysis, lower-leg girth and body composition measurements, strength testing, and gastrocnemius muscle biopsies. Muscle was analyzed for mRNA expression of markers in the ubiquitin and calpain systems, myostatin, TNF-α, and NF-κB. Results. All genes of interest increased over time (P<.05, but there was no difference between groups. Lower-leg girth decreased over time (P=0.02; however, there were no significant changes in body composition or strength. Conclusion. Short-term lower-limb disuse, despite the absence of significant muscle atrophy, is associated with increases in skeletal muscle gene expression of several proteolysis-related genes. These changes do not appear to be altered by oral PAA supplementation.

  3. Increased expression of fatty-acid and calcium metabolism genes in failing human heart.

    Directory of Open Access Journals (Sweden)

    Vanessa García-Rúa

    Full Text Available BACKGROUND: Heart failure (HF involves alterations in metabolism, but little is known about cardiomyopathy-(CM-specific or diabetes-independent alterations in gene expression of proteins involved in fatty-acid (FA uptake and oxidation or in calcium-(Ca(2+-handling in the human heart. METHODS: RT-qPCR was used to quantify mRNA expression and immunoblotting to confirm protein expression in left-ventricular myocardium from patients with HF (n = 36 without diabetes mellitus of ischaemic (ICM, n = 16 or dilated (DCM, n = 20 cardiomyopathy aetiology, and non-diseased donors (CTL, n = 6. RESULTS: Significant increases in mRNA of genes regulating FA uptake (CD36 and intracellular transport (Heart-FA-Binding Protein (HFABP were observed in HF patients vs CTL. Significance was maintained in DCM and confirmed at protein level, but not in ICM. mRNA was higher in DCM than ICM for peroxisome-proliferator-activated-receptor-alpha (PPARA, PPAR-gamma coactivator-1-alpha (PGC1A and CD36, and confirmed at the protein level for PPARA and CD36. Transcript and protein expression of Ca(2+-handling genes (Two-Pore-Channel 1 (TPCN1, Two-Pore-Channel 2 (TPCN2, and Inositol 1,4,5-triphosphate Receptor type-1 (IP3R1 increased in HF patients relative to CTL. Increases remained significant for TPCN2 in all groups but for TPCN1 only in DCM. There were correlations between FA metabolism and Ca(2+-handling genes expression. In ICM there were six correlations, all distinct from those found in CTL. In DCM there were also six (all also different from those found in CTL: three were common to and three distinct from ICM. CONCLUSION: DCM-specific increases were found in expression of several genes that regulate FA metabolism, which might help in the design of aetiology-specific metabolic therapies in HF. Ca(2+-handling genes TPCN1 and TPCN2 also showed increased expression in HF, while HF- and CM-specific positive correlations were found among several FA and Ca(2

  4. Simultaneous determination of gallic acid and gentisic acid in organic anion transporter expressing cells by liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Wang, Li; Halquist, Matthew S; Sweet, Douglas H

    2013-10-15

    In order to elucidate the role of organic anion transporters (OATs) in the renal elimination of gallic acid and gentisic acid, a new, rapid, and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method has been developed and validated for the simultaneous determination of gallic acid and gentisic acid in cell lysate, using Danshensu as the internal standard (IS). After a simple liquid-liquid extraction, the analytes were detected in negative ESI mode using selected reaction monitoring. The precursor-to-product ion transitions (m/z) were 169.0→125.0, 153.1→108.0, and 196.8→135.2 for gallic acid, gentisic acid, and the IS, respectively. Chromatographic separation was achieved on a C18 column using mobile phases consisting of water with 0.1% acetic acid (A) and acetonitrile with 0.05% formic acid. (B) The total run time was 3min and calibration curves were linear over the concentrations of 0.33-2400ng/mL for both compounds (r(2)>0.995). Good precision (between 3.11% and 14.1% RSD) and accuracy (between -12.7% and 11% bias) was observed for quality controls at concentrations of 0.33 (lower limit of quantification), 1, 50, and 2000ng/mL. The mean extraction recovery of gallic acid and gentisic acid was 80.7% and 83.5%, respectively. Results from post-column infusion and post-extraction methods indicated that the analytical method exhibited negligible matrix effects. Finally, this validated assay was successfully applied in a cellular uptake study to determine the intracellular concentrations of gallic acid and gentisic acid in OAT expressing cells.

  5. Shifting boundaries of retinoic acid activity control hindbrain segmental gene expression.

    Science.gov (United States)

    Sirbu, Ioan Ovidiu; Gresh, Lionel; Barra, Jacqueline; Duester, Gregg

    2005-06-01

    Retinoic acid (RA) generated by Raldh2 in paraxial mesoderm is required for specification of the posterior hindbrain, including restriction of Hoxb1 expression to presumptive rhombomere 4 (r4). Hoxb1 expression requires 3' and 5' RA response elements for widespread induction up to r4 and for r3/r5 repression, but RA has previously been detected only from r5-r8, and vHnf1 is required for repression of Hoxb1 posterior to r4 in zebrafish. We demonstrate in mouse embryos that an RA signal initially travels from the paraxial mesoderm to r3, forming a boundary next to the r2 expression domain of Cyp26a1 (which encodes an RA-degrading enzyme). After Hoxb1 induction, the RA boundary quickly shifts to r4/r5, coincident with induction of Cyp26c1 in r4. A functional role for Cyp26c1 in RA degradation was established through examination of RA-treated embryos. Analysis of Raldh2-/- and vHnf1-/- embryos supports a direct role for RA in Hoxb1 induction up to r4 and repression in r3/r5, as well as an indirect role for RA in Hoxb1 repression posterior to r4 via RA induction of vHnf1 up to the r4/r5 boundary. Our findings suggest that Raldh2 and Cyp26 generate shifting boundaries of RA activity, such that r3-r4 receives a short pulse of RA and r5-r8 receives a long pulse of RA. These two pulses of RA activity function to establish expression of Hoxb1 and vHnf1 on opposite sides of the r4/r5 boundary.

  6. An acute dose of gamma-hydroxybutyric acid alters gene expression in multiple mouse brain regions.

    Science.gov (United States)

    Schnackenberg, B J; Saini, U T; Robinson, B L; Ali, S F; Patterson, T A

    2010-10-13

    Gamma-hydroxybutyric acid (GHB) is normally found in the brain in low concentrations and may function as a neurotransmitter, although the mechanism of action has not been completely elucidated. GHB has been used as a general anesthetic and is currently used to treat narcolepsy and alcoholism. Recreational use of GHB is primarily as a "club drug" and a "date rape drug," due to its amnesic effects. For this study, the hypothesis was that behavioral and neurochemical alterations may parallel gene expression changes in the brain after GHB administration. Adult male C57/B6N mice (n=5/group) were administered a single dose of 500 mg/kg GHB (i.p.) and were sacrificed 1, 2 and 4 h after treatment. Control mice were administered saline. Brains were removed and regionally dissected on ice. Total RNA from the hippocampus, cortex and striatum was extracted, amplified and labeled. Gene expression was evaluated using Agilent whole mouse genome 4x44K oligonucleotide microarrays. Microarray data were analyzed by ArrayTrack and differentially expressed genes (DEGs) were identified using P or = 1.7 as the criteria for significance. Principal component analysis (PCA) and Hierarchical Cluster Analysis (HCA) showed that samples from each time point clustered into distinct treatment groups with respect to sacrifice time. Ingenuity pathways analysis (IPA) was used to identify involved pathways. The results show that GHB induces gene expression alterations in hundreds of genes in the hippocampus, cortex and striatum, and the number of affected genes increases throughout a 4-h time course. Many of these DEGs are involved in neurological disease, apoptosis, and oxidative stress.

  7. Reducing saturated fatty acids in Arabidopsis seeds by expression of a Caenorhabditis elegans 16:0-specific desaturase.

    Science.gov (United States)

    Fahy, Deirdre; Scheer, Barbara; Wallis, James G; Browse, John

    2013-05-01

    Plant oilseeds are a major source of nutritional oils. Their fatty acid composition, especially the proportion of saturated and unsaturated fatty acids, has important effects on human health. Because intake of saturated fats is correlated with the incidence of cardiovascular disease and diabetes, a goal of metabolic engineering is to develop oils low in saturated fatty acids. Palmitic acid (16:0) is the most abundant saturated fatty acid in the seeds of many oilseed crops and in Arabidopsis thaliana. We expressed FAT-5, a membrane-bound desaturase cloned from Caenorhabditis elegans, in Arabidopsis using a strong seed-specific promoter. The FAT-5 enzyme is highly specific to 16:0 as substrate, converting it to 16:1∆9; expression of fat-5 reduced the 16:0 content of the seed by two-thirds. Decreased 16:0 and elevated 16:1 levels were evident both in the storage and membrane lipids of seeds. Regiochemical analysis of phosphatidylcholine showed that 16:1 was distributed at both positions on the glycerolipid backbone, unlike 16:0, which is predominately found at the sn-1 position. Seeds from a plant line homozygous for FAT-5 expression were comparable to wild type with respect to seed set and germination, while oil content and weight were somewhat reduced. These experiments demonstrate that targeted heterologous expression of a desaturase in oilseeds can reduce the level of saturated fatty acids in the oil, significantly improving its nutritional value.

  8. Effects of folic acid on epithelial apoptosis and expression of Bcl-2 and p53 in premalignant gastric lesions

    Institute of Scientific and Technical Information of China (English)

    Da-Zhong Cao; Wei-Hao Sun; Xi-Long Ou; Qian Yu; Ting Yu; You-Zhen Zhang; Zi-Ying Wu; Qi-Ping Xue; Yun-Lin Cheng

    2005-01-01

    AIM: To evaluate the effects of folic acid on epithelial apoptosis and expression of Bcl-2 and p53 in the tissues of premalignant gastric lesions.METHODS: Thirty-eight patients, with premalignant gastric lesions including 18 colonic-type intestinal metaplasia(IM)and 20 mild or moderate dysplasia, were randomly divided into a treatment group (n = 19) receiving folic acid 10 mg thrice daily and a control group (n = 19) receiving sucralfate 1 000 mg thrice daily for 3 mo. All patients undervvent endoscopies and four biopsies were taken prior to treatment and repeated after concluding therapy.Folate concentrations in gastric mucosa were measured with chemiluminescent enzyme immunoassay. Epithelial apoptosis and the expression of Bcl-2 and p53 protein in gastric mucosa were detected with flow cytometric assay.RESULTS: The mean of folate concentration in gastric mucosa was 9.03±3.37 μg/g wet wt in the folic acid treatment group, which was significantly higher than 6.83±3.02 μg/g wet wt in the control group. Both the epithelial apoptosis rate and the tumor suppressor p53expression in gastric mucosa significantly increased after folic acid treatment. In contrast, the expression of Bcl-2oncogene protein decreased after folic acid therapy.CONCLUSION: These data indicate that folic acid may play an important role in the chemoprevention of gastric carcinogenesis by enhancing gastric epithelial apoptosis in the patients with premalignant lesions.

  9. Highly expressed amino acid biosynthesis genes revealed by global gene expression analysis of Salmonella enterica serovar Enteritidis during growth in whole egg are not essential for this growth

    DEFF Research Database (Denmark)

    Jakočiūnė, Dzuiga; Herrero-Fresno, Ana; Jelsbak, Lotte;

    2016-01-01

    RNA was extracted from S. Enteritidis using a modified RNA-extraction protocol. Global gene expression during growth in whole egg was compared to growth in LB-medium using DNA array method. Twenty-six genes were significantly upregulated during growth in egg; these belonged to amino acid biosynthesis...

  10. Expression of human dopamine receptor in potato (Solanum tuberosum results in altered tuber carbon metabolism

    Directory of Open Access Journals (Sweden)

    Świędrych Anna

    2005-02-01

    Full Text Available Abstract Background Even though the catecholamines (dopamine, norepinephrine and epinephrine have been detected in plants their role is poorly documented. Correlations between norepinephrine, soluble sugars and starch concentration have been recently reported for potato plants over-expressing tyrosine decarboxylase, the enzyme mediating the first step of catecholamine synthesis. More recently norepinephrine level was shown to significantly increase after osmotic stress, abscisic acid treatment and wounding. Therefore, it is possible that catecholamines might play a role in plant stress responses by modulating primary carbon metabolism, possibly by a mechanism similar to that in animal cells. Since to date no catecholamine receptor has been identified in plants we transformed potato plants with a cDNA encoding human dopamine receptor (HD1. Results Tuber analysis of transgenic plants revealed changes in the activities of key enzymes mediating sucrose to starch conversion (ADP-glucose phosphorylase and sucrose synthase and sucrose synthesis (sucrose phosphate synthase leading to altered content of both soluble sugars and starch. Surprisingly the catecholamine level measured in transgenic plants was significantly increased; the reason for this is as yet unknown. However the presence of the receptor affected a broader range of enzyme activities than those affected by the massive accumulation of norepinephrine reported for plants over-expressing tyrosine decarboxylase. Therefore, it is suggested that the presence of the exogenous receptor activates catecholamine cAMP signalling in plants. Conclusions Our data support the possible involvement of catecholamines in regulating plant carbon metabolism via cAMP signalling pathway.

  11. The uptake transporter OATP8 expression decreases during multistep hepatocarcinogenesis: correlation with gadoxetic acid enhanced MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kitao, Azusa; Matsui, Osamu; Yoneda, Norihide; Kozaka, Kazuto; Shinmura, Rieko; Koda, Wataru; Kobayashi, Satoshi; Gabata, Toshifumi [Kanazawa University Graduate School of Medical Science, Department of Radiology, Kanazawa (Japan); Zen, Yoh [Kanazawa University Graduate School of Medical Science, Human Pathology, Kanazawa (Japan); King' s College Hospital, Institute of Liver Studies, London (United Kingdom); Yamashita, Tatsuya; Kaneko, Shuichi [Kanazawa University Graduate School of Medical Science, Gastroenterology, Kanazawa (Japan); Nakanuma, Yasuni [Kanazawa University Graduate School of Medical Science, Human Pathology, Kanazawa (Japan)

    2011-10-15

    To clarify the changes in organic anion-transporting polypeptide 8 (OATP8) expression and enhancement ratio on gadoxetic acid-enhanced MR imaging in hepatocellular nodules during multistep hepatocarcinogenesis. In imaging analysis, we focused on 71 surgically resected hepatocellular carcinomas (well, moderately and poorly differentiated HCCs) and 1 dysplastic nodule (DN). We examined the enhancement ratio in the hepatobiliary phase of gadoxetic acid enhanced MR imaging [(1/postcontrast T1 value-1/precontrast T1 value)/(1/precontrast T1 value)], then analysed the correlation among the enhancement ratio, tumour differentiation grade and intensity of immunohistochemical OATP8 expression. In pathological analysis, we focused on surgically resected 190 hepatocellular nodules: low-grade DNs, high-grade DNs, early HCCs, well-differentiated, moderately differentiated and poorly differentiated HCCs, including cases without gadoxetic acid-enhanced MR imaging. We evaluated the correlation between the immunohistochemical OATP8 expression and the tumour differentiation grade. The enhancement ratio of HCCs decreased in accordance with the decline in tumour differentiation (P < 0.0001, R = 0.28) and with the decline of OATP8 expression (P < 0.0001, R = 0.81). The immunohistochemical OATP8 expression decreased from low-grade DNs to poorly differentiated HCCs (P < 0.0001, R = 0.15). The immunohistochemical expression of OATP8 significantly decreases during multistep hepatocarcinogenesis, which may explain the decrease in enhancement ratio on gadoxetic acid-enhanced MR imaging. (orig.)

  12. Gene expression, serum amino acid levels, and growth performance of pigs fed dietary leucine and lysine at different ratios.

    Science.gov (United States)

    García, H; Morales, A; Araiza, A; Htoo, J K; Cervantes, M

    2015-03-06

    We examined 96 pigs (28.1 ± 0.83 kg) to analyze the effect of Leu:Lys ratios on expression of the cationic amino acid transporters b(0,+) and CAT-1 in the jejunum and liver as well as myosin expression in 2 muscles to estimate the optimum standardized ileal digestible (SID) Leu:Lys ratio for growth rate and efficiency. A wheat-and wheat bran-based diets were formulated to meet the requirements of SID amino acids other than Leu (0.70%) and Lys (0.80%). L-Leu was added to the basal diet in 5 SID Leu:Lys ratios (88, 100, 120, 140, and 160% in diets 1-5). Tissue samples were collected from 8 pigs with ratios of 88, 120, and 160%. Relative expression of b(0,+), CAT-1, and myosin was analyzed. b(0,+) expression in the jejunum was higher but lower in the liver of pigs with the 120% ratio compared to those with the 88 or 160% ratio; myosin expression in longissimus dorsi was also higher in pigs with the 120% ratio (P pigs with 120 or 160% ratios than in pigs with 88%. Serum concentration of nearly all amino acids decreased with excess dietary Leu (P dietary Leu:Lys ratio affects the expression of genes coding for amino acid transporters and myosin, the availability of Lys, and the growth rate and efficiency in pigs.

  13. Palmitic acid suppresses apolipoprotein M gene expression via the pathway of PPARβ/δ in HepG2 cells.

    Science.gov (United States)

    Luo, Guanghua; Shi, Yuanping; Zhang, Jun; Mu, Qinfeng; Qin, Li; Zheng, Lu; Feng, Yuehua; Berggren-Söderlund, Maria; Nilsson-Ehle, Peter; Zhang, Xiaoying; Xu, Ning

    2014-02-28

    It has been demonstrated that apolipoprotein M (APOM) is a vasculoprotective constituent of high density lipoprotein (HDL), which could be related to the anti-atherosclerotic property of HDL. Investigation of regulation of APOM expression is of important for further exploring its pathophysiological function in vivo. Our previous studies indicated that expression of APOM could be regulated by platelet activating factor (PAF), transforming growth factors (TGF), insulin-like growth factor (IGF), leptin, hyperglycemia and etc., in vivo and/or in vitro. In the present study, we demonstrated that palmitic acid could significantly inhibit APOM gene expression in HepG2 cells. Further study indicated neither PI-3 kinase (PI3K) inhibitor LY294002 nor protein kinase C (PKC) inhibitor GFX could abolish palmitic acid induced down-regulation of APOM expression. In contrast, the peroxisome proliferator-activated receptor beta/delta (PPARβ/δ) antagonist GSK3787 could totally reverse the palmitic acid-induced down-regulation of APOM expression, which clearly demonstrates that down-regulation of APOM expression induced by palmitic acid is mediated via the PPARβ/δ pathway.

  14. Enhanced production of recombinant Escherichia coli glutamate decarboxylase through optimization of induction strategy and addition of pyridoxine.

    Science.gov (United States)

    Su, Lingqia; Huang, Yan; Wu, Jing

    2015-12-01

    This report describes the optimization of recombinant Escherichia coli glutamate decarboxylase (GAD) production from engineered E. coli BL21(DE3) in a 3-L fermentor. Investigation of different induction strategies revealed that induction was optimal when the temperature was maintained at 30°C, the inducer (lactose) was fed at a rate of 0.2 g L(-1)h(-1), and protein expression was induced when the cell density (OD600) reached 50. Under these conditions, the GAD activity of 1273.8 U mL(-1) was achieved. Because GAD is a pyridoxal 5'-phosphate (PLP)-dependent enzyme, the effect of supplementing the medium with pyridoxine hydrochloride (PN), a cheap and stable PLP precursor, on GAD production was also investigated. When the culture medium was supplemented with PN to a concentration of 2mM at the initiation of protein expression, and then again 10h later, the GAD activity reached 3193.4 U mL(-1), which represented the highest GAD production ever reported.

  15. Calmodulin binding to glutamate decarboxylase is required for regulation of glutamate and GABA metabolism and normal development in plants.

    Science.gov (United States)

    Baum, G; Lev-Yadun, S; Fridmann, Y; Arazi, T; Katsnelson, H; Zik, M; Fromm, H

    1996-06-17

    Glutamate decarboxylase (GAD) catalyzes the decarboxylation of glutamate to CO2 and gamma-aminobutyrate (GABA). GAD is ubiquitous in prokaryotes and eukaryotes, but only plant GAD has been shown to bind calmodulin (CaM). Here, we assess the role of the GAD CaM-binding domain in vivo. Transgenic tobacco plants expressing a mutant petunia GAD lacking the CaM-binding domain (GADdeltaC plants) exhibit severe morphological abnormalities, such as short stems, in which cortex parenchyma cells fail to elongate, associated with extremely high GABA and low glutamate levels. The morphology of transgenic plants expressing the full-length GAD (GAD plants) is indistinguishable from that of wild-type (WT) plants. In WT and GAD plant extracts, GAD activity is inhibited by EGTA and by the CaM antagonist trifluoperazine, and is associated with a CaM-containing protein complex of approximately 500 kDa. In contrast, GADdeltaC plants lack normal GAD complexes, and GAD activity in their extracts is not affected by EGTA and trifluoperazine. We conclude that CaM binding to GAD is essential for the regulation of GABA and glutamate metabolism, and that regulation of GAD activity is necessary for normal plant development. This study is the first to demonstrate an in vivo function for CaM binding to a target protein in plants.

  16. Enhanced triterpene accumulation in Panax ginseng hairy roots overexpressing mevalonate-5-pyrophosphate decarboxylase and farnesyl pyrophosphate synthase.

    Science.gov (United States)

    Kim, Yong-Kyoung; Kim, Yeon Bok; Uddin, Md Romij; Lee, Sanghyun; Kim, Soo-Un; Park, Sang Un

    2014-10-17

    To elucidate the function of mevalonate-5-pyrophosphate decarboxylase (MVD) and farnesyl pyrophosphate synthase (FPS) in triterpene biosynthesis, the genes governing the expression of these enzymes were transformed into Panax ginseng hairy roots. All the transgenic lines showed higher expression levels of PgMVD and PgFPS than that by the wild-type control. Among the hairy root lines transformed with PgMVD, M18 showed the highest level of transcription compared to the control (14.5-fold higher). Transcriptions of F11 and F20 transformed with PgFPS showed 11.1-fold higher level compared with control. In triterpene analysis, M25 of PgMVD produced 4.4-fold higher stigmasterol content (138.95 μg/100 mg, dry weight [DW]) than that by the control; F17 of PgFPS showed the highest total ginsenoside (36.42 mg/g DW) content, which was 2.4-fold higher compared with control. Our results indicate that metabolic engineering in P. ginseng was successfully achieved through Agrobacterium rhizogenes-mediated transformation and that the accumulation of phytosterols and ginsenosides was enhanced by introducing the PgMVD and PgFPS genes into the hairy roots of the plant. Our results suggest that PgMVD and PgFPS play an important role in the triterpene biosynthesis of P. ginseng.

  17. 鸟氨酸脱羧酶和c-myc在胃癌及其癌前病变组织中的表达及意义%Expression of ornithine decarboxylase and c-myc in gastric cancer and premalignant lesions and its significance

    Institute of Scientific and Technical Information of China (English)

    魏小娟; 王云溪

    2016-01-01

    Objective:To detect the expression of ODC and c-myc in chronic superficial gastritis, intestinal metaplasia, atypical hy-perplasia and gastric carcinoma, to explore the correlation and significance of the expression of ODC and c-myc in gastric carcinoma and precancerous lesions.Methods:The expressions of ODC and c-myc were detected by RT-PCR and immunohistochemistry in 18 cases of chronic superficial gastritis( CSG) , 18 chronic atrophic gastritis with intestinal metaplasia CAG( with IM) ,12 gastric dysplasia ( DYS) and 30 gastric carcinoma ( GC) , to explore the correlation between ODC and c-myc and their relationship with precancerous gastric le-sions.Results:The expression of ODC in CAG with IM, DYS and GC was significantly higher than that in CSG(P<0.01).The expres-sion of c-myc was significantly higher in GC comparing with CSG and CAG with IM (P<0.01).In addition, ODC and c-myc positive immunostaining rates were significantly higher in poorly-differentiated GC than in well-differentiated GC (P<0.01).The expression of ODC was positively correlated with c-myc at different stages of gastric carcinogenesis.Conclusions:ODC may play an important role as carcinogenic factor, and c-myc promotes cell proliferation by inducing ODC expression.Detecting both markers together may help in ear-ly diagnosis of gastric carcinoma.%及蛋白的表达。结果:ODC mRNA及蛋白在萎缩性胃炎肠化生( CAG与IM)、不典型增生( DYS)及胃癌( GC)组织中的表达水平显著高于浅表性胃炎(CSG)(P<0.01)。 c-myc mRNA及蛋白在胃癌(GC)组织中的表达水平显著高于浅表性胃炎(CSG)、萎缩性胃炎肠化生(CAG with IM)(P<0.01),ODC和c-myc在中低分化腺癌的表达水平显著高于高分化腺癌(P<0.05)。 ODC与c-myc在胃粘膜癌变多阶段中的表达呈正相关( P<0.01)。结论:ODC作为致癌因子在胃癌发生中有重要作用,且c-myc通过促进ODC的

  18. Jasmonic acid/methyl jasmonate accumulate in wounded soybean hypocotyls and modulate wound gene expression.

    Science.gov (United States)

    Creelman, R A; Tierney, M L; Mullet, J E

    1992-06-01

    Jasmonic acid (JA) and its methyl ester, methyl jasmonate (MeJA), are plant lipid derivatives that resemble mammalian eicosanoids in structure and biosynthesis. These compounds are proposed to play a role in plant wound and pathogen responses. Here we report the quantitative determination of JA/MeJA in planta by a procedure based on the use of [13C,2H3]MeJA as an internal standard. Wounded soybean (Glycine max [L] Merr. cv. Williams) stems rapidly accumulated MeJA and JA. Addition of MeJA to soybean suspension cultures also increased mRNA levels for three wound-responsive genes (chalcone synthase, vegetative storage protein, and proline-rich cell wall protein) suggesting a role for MeJA/JA in the mediation of several changes in gene expression associated with the plants' response to wounding.

  19. Lipoprotein Lipase, Tissue Expression and Effects on Genes Related to Fatty Acid Synthesis in Goat Mammary Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Wang-Sheng Zhao

    2014-12-01

    Full Text Available Lipoprotein lipase (LPL serves as a central factor in hydrolysis of triacylglycerol and uptake of free fatty acids from the plasma. However, there are limited data concerning the action of LPL on the regulation of milk fat synthesis in goat mammary gland. In this investigation, we describe the cloning and sequencing of the LPL gene from Xinong Saanen dairy goat mammary gland, along with a study of its phylogenetic relationships. Sequence analysis showed that goat LPL shares similarities with other species including sheep, bovine, human and mouse. LPL mRNA expression in various tissues determined by RT-qPCR revealed the highest expression in white adipose tissue, with lower expression in heart, lung, spleen, rumen, small intestine, mammary gland, and kidney. Expression was almost undetectable in liver and muscle. The expression profiles of LPL gene in mammary gland at early, peak, mid, late lactation, and the dry period were also measured. Compared with the dry period, LPL mRNA expression was markedly greater at early lactation. However, compared with early lactation, the expression was lower at peak lactation and mid lactation. Despite those differences, LPL mRNA expression was still greater at peak, mid, and late lactation compared with the dry period. Using goat mammary epithelial cells (GMEC, the in vitro knockdown of LPL via shRNA or with Orlistat resulted in a similar degree of down-regulation of LPL (respectively. Furthermore, knockdown of LPL was associated with reduced mRNA expression of SREBF1, FASN, LIPE and PPARG but greater expression of FFAR3. There was no effect on ACACA expression. Orlistat decreased expression of LIPE, FASN, ACACA, and PPARG, and increased FFAR3 and SREBF1 expression. The pattern of LPL expression was similar to the changes in milk fat percentage in lactating goats. Taken together, results suggest that LPL may play a crucial role in fatty acid synthesis.

  20. Cloning and expression of Chromobacterium violaceum phenylalanine hydroxylase in Escherichia coli and comparison of amino acid sequence with mammalian aromatic amino acid hydroxylases.

    Science.gov (United States)

    Onishi, A; Liotta, L J; Benkovic, S J

    1991-10-05

    The complete amino acid sequence (296 amino acids) of Chromobacterium violaceum phenylalanine hydroxylase (PAH) was determined by nucleotide analysis of a DNA clone isolated using both a synthetic oligonucleotide probe based on the NH2-terminal amino acid sequence and an antibody against this enzyme. The ApaL I fragment (approximately 1.9 kilobase pairs) containing the entire PAH gene was subcloned in pBluescript II and induced by isopropyl-beta-D-thiogalactopyranoside. In order to eliminate fusion proteins the XbaI/ClaI fragment which contained the PAH gene from the Bluescript construct was subcloned into pMAC 5-8 containing the TAC promoter. The recombinant protein reacts with antibody raised to authentic C. violaceum PAH and its NH2-terminal 20-amino acid sequence and COOH-terminal amino acid residue were identical with the wild-type protein. Key physical and chemical characteristics of the recombinant protein, i.e. its copper content and Michaelis-Menten parameters, were the same as wild-type. Comparison of amino acid sequences revealed a highly conserved region between C. violaceum PAH and three different mammalian aromatic amino acid hydroxylases. This conserved area may well be a catalytically important domain of these pterin- and metal-requiring aromatic amino acid hydroxylases. The over-expression of C. violaceum PAH in Escherichia coli will facilitate the analysis of the enzyme mechanism by various spectroscopic methods.

  1. Abscisic Acid Regulation of Root Hydraulic Conductivity and Aquaporin Gene Expression Is Crucial to the Plant Shoot Growth Enhancement Caused by Rhizosphere Humic Acids.

    Science.gov (United States)

    Olaetxea, Maite; Mora, Verónica; Bacaicoa, Eva; Garnica, María; Fuentes, Marta; Casanova, Esther; Zamarreño, Angel M; Iriarte, Juan C; Etayo, David; Ederra, Iñigo; Gonzalo, Ramón; Baigorri, Roberto; García-Mina, Jose M

    2015-12-01

    The physiological and metabolic mechanisms behind the humic acid-mediated plant growth enhancement are discussed in detail. Experiments using cucumber (Cucumis sativus) plants show that the shoot growth enhancement caused by a structurally well-characterized humic acid with sedimentary origin is functionally associated with significant increases in abscisic acid (ABA) root concentration and root hydraulic conductivity. Complementary experiments involving a blocking agent of cell wall pores and water root transport (polyethylenglycol) show that increases in root hydraulic conductivity are essential in the shoot growth-promoting action of the model humic acid. Further experiments involving an inhibitor of ABA biosynthesis in root and shoot (fluridone) show that the humic acid-mediated enhancement of both root hydraulic conductivity and shoot growth depended on ABA signaling pathways. These experiments also show that a significant increase in the gene expression of the main root plasma membrane aquaporins is associated with the increase of root hydraulic conductivity caused by the model humic acid. Finally, experimental data suggest that all of these actions of model humic acid on root functionality, which are linked to its beneficial action on plant shoot growth, are likely related to the conformational structure of humic acid in solution and its interaction with the cell wall at the root surface.

  2. Differential expression of fatty acid synthase genes, Acl, Fat and Kas, in Capsicum fruit.

    Science.gov (United States)

    Aluru, Maneesha R; Mazourek, Michael; Landry, Laurie G; Curry, Jeanne; Jahn, Molly; O'Connell, Mary A

    2003-07-01

    The biosynthesis of capsaicinoids in the placenta of chilli fruit is modelled to require components of the fatty acid synthase (FAS) complex. Three candidate genes for subunits in this complex, Kas, Acl, and Fat, isolated based on differential expression, were characterized. Transcription of these three genes was placental-specific and RNA abundance was positively correlated with degree of pungency. Kas and Acl were mapped to linkage group 1 and Fat to linkage group 6. None of the genes is linked to the pungency locus, C, on linkage group 2. KAS accumulation was positively correlated with pungency. Western blots of placental extracts and histological sections both demonstrated that the accumulation of this enzyme was correlated with fruit pungency and KAS was immunolocalized to the expected cell layer, the placental epidermis. Enzyme activity of the recombinant form of the placental-specific KAS was confirmed using crude cell extracts. These FAS components are fruit-specific members of their respective gene families. These genes are predicted to be associated with Capsicum fruit traits, for example, capsaicinoid biosynthesis or fatty acid biosynthesis necessary for placental development.

  3. Glycinergic-Fipronil Uptake Is Mediated by an Amino Acid Carrier System and Induces the Expression of Amino Acid Transporter Genes in Ricinus communis Seedlings.

    Science.gov (United States)

    Xie, Yun; Zhao, Jun-Long; Wang, Chuan-Wei; Yu, Ai-Xin; Liu, Niu; Chen, Li; Lin, Fei; Xu, Han-Hong

    2016-05-18

    Phloem-mobile insecticides are efficient for piercing and sucking insect control. Introduction of sugar or amino acid groups to the parent compound can improve the phloem mobility of insecticides, so a glycinergic-fipronil conjugate (GlyF), 2-(3-(3-cyano-1-(2,6-dichloro-4-(trifluoromethyl)phenyl)-4-((trifluoromethyl)sulfinyl)-1H-pyrazole-5-yl)ureido) acetic acid, was designed and synthesized. Although the "Kleier model" predicted that this conjugate is not phloem mobile, GlyF can be continually detected during a 5 h collection of Ricinus communis phloem sap. Furthermore, an R. communis seedling cotyledon disk uptake experiment demonstrates that the uptake of GlyF is sensitive to pH, carbonyl cyanide m-chlorophenylhydrazone (CCCP), temperature, and p-chloromercuribenzenesulfonic acid (pCMBS) and is likely mediated by amino acid carrier system. To explore the roles of amino acid transporters (AATs) in GlyF uptake, a total of 62 AAT genes were identified from the R. communis genome in silico. Phylogenetic analysis revealed that AATs in R. communis were organized into the ATF (amino acid transporter) and APC (amino acid, polyaminem and choline transporter) superfamilies, with five subfamilies in ATF and two in APC. Furthermore, the expression profiles of 20 abundantly expressed AATs (cycle threshold (Ct) values communis seedlings. On the basis of the observation that the expression profile of the four candidate genes is similar to the time course observation for GlyF foliar disk uptake, it is suggested that those four genes are possible candidates involved in the uptake of GlyF. These results contribute to a better understanding of the mechanism of GlyF uptake as well as phloem loading from a molecular biology perspective and facilitate functional characterization of candidate AAT genes in future studies.

  4. THE EFFECTS OF RETINOIC ACID ON EXPRESSION OF C-MYC, C-FOS IN LEUKEMIC PROMYELOCYTES

    Institute of Scientific and Technical Information of China (English)

    邵国英; 徐荣婷; 孙关林; 欧阳仁荣; 应大明

    1992-01-01

    The expression of c-myc, c-fos of leukemic promyelocytes (HL-60 and acute promyelocytic leukemia cells) from 18 acute promyelocytic leukemia (APL) patients treated with all-trans retinoic acid (RA) in vitro was studied. There was no expression of c-fos in HL-60 cells and APL cells from 17 patients. But in one case, a slight expression of c-fos in leukemic cells was observed, and the alteration of expression level was found during the treatment of the cells with RA in vitro. The expression of c-myc in HL-60 cells induced by RA was altered, decrease in the early, increase in the middle, and decline in the later stage were found. The c-myc expression in leukemic cells of eighteen APL patients was variable. There was c-myc expression in eleven APL cells, but no expression in the others. The APL cells with c-myc expression were treated with RA in vitro to observe the kinetic changes of c-myc RNA level. The results showed that the expression of c-myc was gradually decreased except in few cases. Using in situ hybridization technique for detecting the alteration of c-myc expression in leukemic cells of two APL patients. the high level of c-myc before RA treatment and low level of c-myc expression after obtaining complete remission induced by RA were found. The possibility of different proto-oncogenes implicated differentiation was discussed.

  5. Folic Acid supplementary reduce the incidence of adenocarcinoma in a mouse model of colorectal cancer: microarray gene expression profile

    Directory of Open Access Journals (Sweden)

    Lin Yan-Wei

    2011-12-01

    Full Text Available Abstract Background Whether Folic acid is a potential drug that may prevent the progression of colorectal carcinoma and when to use are important healthy issues we focus on. Our study is to examine the effect of folic acid on the development of the CRC and the optimal time folic acid should be provided in a mouse-ICR model induced by 1, 2-Dimethylhydrazine. Also, we investigated the gene expression profile of this model related to folic acid. Method Female ICR mouse (n = 130 were divided into 7 groups either with the treatment of 1, 2-Dimethylhydrazine (20 mg/kg bodyweight weekly or folic acid (8 mg/kg bodyweight twice a week for 12 or 24 weeks. Using a 4 × 44 K Agilent whole genome oligo microarray assay, different gene expression among groups (NS, DMH, FA2, FA3 were identified and selected genes were validated by real-time polymerase chain reaction. Results Animals with a supplementary of folic acid showed a significant decrease in the incidence, the maximum diameter and multiplicity of adenocarcinomas (P Conclusion Our study demonstrated that folic acid supplementary was significantly associated with the decrease risk of CRC. And the subgroup of providing folic acid without precancerous lesions was more effective than that with precancerous lesions.

  6. Impact of methods used to express levels of circulating fatty acids on the degree and direction of associations with blood lipids in humans.

    Science.gov (United States)

    Sergeant, Susan; Ruczinski, Ingo; Ivester, Priscilla; Lee, Tammy C; Morgan, Timothy M; Nicklas, Barbara J; Mathias, Rasika A; Chilton, Floyd H

    2016-01-28

    Numerous studies have examined relationships between disease biomarkers (such as blood lipids) and levels of circulating or cellular fatty acids. In such association studies, fatty acids have typically been expressed as the percentage of a particular fatty acid relative to the total fatty acids in a sample. Using two human cohorts, this study examined relationships between blood lipids (TAG, and LDL, HDL or total cholesterol) and circulating fatty acids expressed either as a percentage of total or as concentration in serum. The direction of the correlation between stearic acid, linoleic acid, dihomo-γ-linolenic acid, arachidonic acid and DHA and circulating TAG reversed when fatty acids were expressed as concentrations v. a percentage of total. Similar reversals were observed for these fatty acids when examining their associations with the ratio of total cholesterol:HDL-cholesterol. This reversal pattern was replicated in serum samples from both human cohorts. The correlations between blood lipids and fatty acids expressed as a percentage of total could be mathematically modelled from the concentration data. These data reveal that the different methods of expressing fatty acids lead to dissimilar correlations between blood lipids and certain fatty acids. This study raises important questions about how such reversals in association patterns impact the interpretation of numerous association studies evaluating fatty acids and their relationships with disease biomarkers or risk.

  7. Indole-3-acetic acid (IAA) induced changes in oil content, fatty acid profiles and expression of four fatty acid biosynthetic genes in Chlorella vulgaris at early stationary growth phase.

    Science.gov (United States)

    Jusoh, Malinna; Loh, Saw Hong; Chuah, Tse Seng; Aziz, Ahmad; Cha, Thye San

    2015-03-01

    Microalgae lipids and oils are potential candidates for renewable biodiesel. Many microalgae species accumulate a substantial amount of lipids and oils under environmental stresses. However, low growth rate under these adverse conditions account for the decrease in overall biomass productivity which directly influence the oil yield. This study was undertaken to investigate the effect of exogenously added auxin (indole-3-acetic acid; IAA) on the oil content, fatty acid compositions, and the expression of fatty acid biosynthetic genes in Chlorella vulgaris (UMT-M1). Auxin has been shown to regulate growth and metabolite production of several microalgae. Results showed that oil accumulation was highest on days after treatment (DAT)-2 with enriched levels of palmitic (C16:0) and stearic (C18:0) acids, while the linoleic (C18:2) and α-linolenic (C18:3n3) acids levels were markedly reduced by IAA. The elevated levels of saturated fatty acids (C16:0 and C18:0) were consistent with high expression of the β-ketoacyl ACP synthase I (KAS I) gene, while low expression of omega-6 fatty acid desaturase (ω-6 FAD) gene was consistent with low production of C18:2. However, the increment of stearoyl-ACP desaturase (SAD) gene expression upon IAA induction did not coincide with oleic acid (C18:1) production. The expression of omega-3 fatty acid desaturase (ω-3 FAD) gene showed a positive correlation with the synthesis of PUFA and C18:3n3.

  8. Effects of Salvianolic Acid B on Protein Expression in Human Umbilical Vein Endothelial Cells

    Science.gov (United States)

    Chang, Tsong-Min; Shi, Guey-Yueh; Wu, Hua-Lin; Wu, Chieh-Hsi; Su, Yan-Di; Wang, Hui-Lin; Wen, Hsin-Yun; Huang, Huey-Chun

    2011-01-01

    Salvianolic acid B (Sal B), a pure water-soluble compound extracted from Radix Salviae miltiorrhizae, has been reported to possess potential cardioprotective efficacy. To identify proteins or pathways by which Sal B might exert its protective activities on the cardiovascular system, two-dimensional gel electrophoresis-based comparative proteomics was performed, and proteins altered in their expression level after Sal B treatment were identified by MALDI-TOF MS/MS. Human umbilical vein endothelial cells (HUVECs) were incubated at Sal B concentrations that can be reached in human plasma by pharmacological intervention. Results indicated that caldesmon, an actin-stabilizing protein, was downregulated in Sal B-exposed HUVECs. Proteins that showed increased expression levels upon Sal B treatment were vimentin, T-complex protein 1, protein disulfide isomerase, tropomyosin alpha, heat shock protein beta-1, UBX domain-containing protein 1, alpha enolase, and peroxiredoxin-2. Additionally, Sal B leads to increased phosphorylation of nucleophosmin in a dose-dependent manner and promotes proliferation of HUVECs. We found that Sal B exhibited a coordinated regulation of enzymes and proteins involved in cytoskeletal reorganization, oxidative stress, and cell growth. Our investigation would provide understanding to the endothelium protection information of Sal B. PMID:21423689

  9. Effects of Salvianolic Acid B on Protein Expression in Human Umbilical Vein Endothelial Cells

    Directory of Open Access Journals (Sweden)

    Tsong-Min Chang

    2011-01-01

    Full Text Available Salvianolic acid B (Sal B, a pure water-soluble compound extracted from Radix Salviae miltiorrhizae, has been reported to possess potential cardioprotective efficacy. To identify proteins or pathways by which Sal B might exert its protective activities on the cardiovascular system, two-dimensional gel electrophoresis-based comparative proteomics was performed, and proteins altered in their expression level after Sal B treatment were identified by MALDI-TOF MS/MS. Human umbilical vein endothelial cells (HUVECs were incubated at Sal B concentrations that can be reached in human plasma by pharmacological intervention. Results indicated that caldesmon, an actin-stabilizing protein, was downregulated in Sal B-exposed HUVECs. Proteins that showed increased expression levels upon Sal B treatment were vimentin, T-complex protein 1, protein disulfide isomerase, tropomyosin alpha, heat shock protein beta-1, UBX domain-containing protein 1, alpha enolase, and peroxiredoxin-2. Additionally, Sal B leads to increased phosphorylation of nucleophosmin in a dose-dependent manner and promotes proliferation of HUVECs. We found that Sal B exhibited a coordinated regulation of enzymes and proteins involved in cytoskeletal reorganization, oxidative stress, and cell growth. Our investigation would provide understanding to the endothelium protection information of Sal B.

  10. Expression, solubilisation, and purification of a functional CMP-sialic acid transporter in Pichia pastoris.

    Science.gov (United States)

    Maggioni, Andrea; Hadley, Barbara; von Itzstein, Mark; Tiralongo, Joe

    2014-09-01

    Membrane proteins, including solute transporters play crucial roles in cellular function and have been implicated in a variety of important diseases, and as such are considered important targets for drug development. Currently the drug discovery process is heavily reliant on the structural and functional information discerned from high-resolution crystal structures. However, membrane protein structure determination is notoriously difficult, due in part to challenges faced in their expression, solubilisation and purification. The CMP-sialic acid transporter (CST) is considered to be an attractive target for drug discovery. CST inhibition reduces cancer cell sialylation and decreases the metastatic potential of cancer cells and to date, no crystal structure of the CST, or any other nucleotide sugar transporter exists. Here we describe the optimised conditions for expression in Pichia pastoris, solubilisation using n-nonyl β-d-maltopyranoside (NM) and single step purification of a functional CST. Importantly we show that despite being able to solubilise and purify the CST using a number of different detergents, only NM was able to maintain CST functionality.

  11. Expression of Lactate Dehydrogenase in Aspergillus niger for L-Lactic Acid Production.

    Science.gov (United States)

    Dave, Khyati K; Punekar, Narayan S

    2015-01-01

    Different engineered organisms have been used to produce L-lactate. Poor yields of lactate at low pH and expensive downstream processing remain as bottlenecks. Aspergillus niger is a prolific citrate producer and a remarkably acid tolerant fungus. Neither a functional lactate dehydrogenase (LDH) from nor lactate production by A. niger is reported. Its genome was also investigated for the presence of a functional ldh. The endogenous A. niger citrate synthase promoter relevant to A. niger acidogenic metabolism was employed to drive constitutive expression of mouse lactate dehydrogenase (mldhA). An appraisal of different branches of the A. niger pyruvate node guided the choice of mldhA for heterologous expression. A high copy number transformant C12 strain, displaying highest LDH specific activity, was analyzed under different growth conditions. The C12 strain produced 7.7 g/l of extracellular L-lactate from 60 g/l of glucose, in non-neutralizing minimal media. Significantly, lactate and citrate accumulated under two different growth conditions. Already an established acidogenic platform, A. niger now promises to be a valuable host for lactate production.

  12. Effect of eicosapentaenoic acid on the expression of ABCG1 gene in the human monocyte THP-1 cells.

    Directory of Open Access Journals (Sweden)

    Mostafa Moradi Sarabi

    2014-03-01

    Full Text Available Cardiovascular disease (CVD is the leading cause of death and disability in developed countries. Atherosclerosis is the major cause of CVD, accounting for about half of the attributed deaths. Cholesterol homeostasis is one of the most important factors in atherosclerosis. ATP-Binding cassette transporters cholesterol. Omega (ω 3 fatty acids are important ligands for regulation of ABC transporters such as ABCG1. Concern has been raised that the low absolute intakes of EPA and high ratios of ω-6 polyunsaturated fatty acids (ω-6 PUFA to EPA may predispose some individuals to CVD. Eicosapentaenoic acid (EPA is the most abundant ω3 fatty acid in the diet. The objective of this study was to evaluate the effect of different concentrations of EPA on the expression of ABCG1 gene in the human monocyte THP-1 cells. In this study, THP-1 cells were cultured in RPMI 1640 medium, THP-1 monocytes were then differentiated to macrophages with PMA (phorbol myristic acid and stimulated with 50, 75 and 100 μM of EPA for 24 h at 37°C. We examined the effects of EPA treatment on the expression of ABCG1 gene using Quantitative Real time RT-PCR (qRT-PCR. Our results, indicate that ABCG1 mRNA expression was significantly reduced by 50, 75 and 100 μM EPA fatty acid treatments as compared to the control cells (р = 0.009, р < 0.001 and р = 0.002, respectively. These results suggest that polyunsaturated fatty acids (PUFAs such as EPA have an effect on the cholesterol homeostasis in macrophages, and they can change the expression of ABCG1 gene. It seems that EPA has different effects on gene expression and lipid metabolism.

  13. Effect of eicosapentaenoic acid on the expression of ABCG1 gene in the human monocyte THP-1 cells.

    Science.gov (United States)

    Moradi Sarabi, Mostafa; Doosti, Mahmood; Einollahi, Nahid; Hesami, Soroush Shahryar; Dashti, Nasrin

    2014-01-01

    Cardiovascular disease (CVD) is the leading cause of death and disability in developed countries. Atherosclerosis is the major cause of CVD, accounting for about half of the attributed deaths. Cholesterol homeostasis is one of the most important factors in atherosclerosis. ATP-Binding cassette transporters cholesterol. Omega (ω) 3 fatty acids are important ligands for regulation of ABC transporters such as ABCG1. Concern has been raised that the low absolute intakes of EPA and high ratios of ω-6 polyunsaturated fatty acids (ω-6 PUFA) to EPA may predispose some individuals to CVD. Eicosapentaenoic acid (EPA) is the most abundant ω3 fatty acid in the diet. The objective of this study was to evaluate the effect of different concentrations of EPA on the expression of ABCG1 gene in the human monocyte THP-1 cells. In this study, THP-1 cells were cultured in RPMI 1640 medium, THP-1 monocytes were then differentiated to macrophages with PMA (phorbol myristic acid) and stimulated with 50, 75 and 100 μM of EPA for 24 h at 37°C. We examined the effects of EPA treatment on the expression of ABCG1 gene using Quantitative Real time RT-PCR (qRT-PCR). Our results, indicate that ABCG1 mRNA expression was significantly reduced by 50, 75 and 100 μM EPA fatty acid treatments as compared to the control cells (р = 0.009, р < 0.001 and р = 0.002, respectively). These results suggest that polyunsaturated fatty acids (PUFAs) such as EPA have an effect on the cholesterol homeostasis in macrophages, and they can change the expression of ABCG1 gene. It seems that EPA has different effects on gene expression and lipid metabolism.

  14. Differential expression of the α2,3-sialic acid residues in breast cancer is associated with metastatic potential.

    Science.gov (United States)

    Cui, Hongxia; Lin, Yu; Yue, Liling; Zhao, Xuemei; Liu, Jicheng

    2011-05-01

    Aberrant sialylation is closely associated with the malignant phenotype of cancer cells and metastatic potential. However, the precise nature of the molecules in breast cancers has not been unveiled. In this study, we investigated the expression levels of α2,3-sialic acid residues of 50 primary tumor cases, 50 pair-matched lymph node metastasis tumor samples and in the MDA-MB-231, T-47D and MCF-7 breast cancer cell lines with different metastatic potential. The expression of α2,3-sialic acid residues was analyzed by histochemistry, cytochemistry and flow cytometry with Maackia amurensis lectin (MAL). The invasion and migration abilities of cells were examined using cell adhesion and transwell in vitro assays. Pair-matched lymph node metastasis tumor samples exhibited higher levels of expression of α2,3-sialic acid residues compared to that of primary tumors (P=0.0432). Furthermore, of 38 tumors cases in T1/T2 stages, 31 (81.58%) had weak staining for MAL, which specifically binds to α2,3-sialic acid residues, whereas of 12 tumor cases in T3/T4 stages, only 1 (8.33%) had weak reactions for MAL. The highly metastatic breast cancer cell line MDA-MB-231 exhibited the strongest binding to MAL and the highest expression levels of α2,3-sialic acid residues among the selected cell lines, depending on mRNA expression levels of α2,3-sialyltransferase gene. The adhesion, invasion and migration activities confirmed that MDA-MB-231 exhibited the greater cell adhesion to, migration toward and invasion to Matrigel. Taken together, the high expression of α2,3-sialic acid residues in breast cancer was associated with metastatic potential. This property may be important for developing new therapeutic approaches for breast cancer.

  15. Determining Effects of Elaidic Acid on PPAR- Gamma Expression in RAW 264.7 Macrophage Cell Line

    Directory of Open Access Journals (Sweden)

    M Doosti

    2012-08-01

    Full Text Available Background: Several dietary factors are involved in cardiovascular coronary heart diseases, including trans fatty acids, which are generally formed during hydrogenation of vegetable oils, a process that causes conversion of liquid oils into semisolid fats. Nowadays, it is well-known that trans fatty acids form a major risk factor in the occurrence and progression of atherosclerosis. On the other hand, it has been identified that some nuclear receptors, such as PPARs, are involved and play important roles in lipid homeostasis and pathogenesis of cardiovascular diseases. Therefore, we studied the effect of elaidic acid on gene expression of peroxisome proliferator activated receptor gamma (PPARγ.Methods: Murine macrophage RAW264.7 cells were treated by 0.5, 1, and 2 mM concentrations of elaidic acid for 6 h. The control group was treated by 50% ethanol (as solvent, equivalent to the amount of ethanol used in 2 mM concentration of elaidic acid. Later, the total RNA was extracted and its cDNA was synthesized. Finally, the quantity of PPARγ gene expression was measured by real-time PCR.Results: Overall, 0.5, 1, and 2 mM concentrations of elaidic acid decreased PPARγ gene expression in RAW264.7 macrophage cell line by -1.36, -1.68, and -3.24 folds compared with the control group, respectively.Conclusion: By decreasing the expression of nuclear receptor PPARγ, elaidic acid causes, intensifies or accelerates the occurrence of cardiovascular diseases, especially atherosclerosis. This finding shows the importance of reducing the consumption of elaidic acid containing foods.

  16. Fatty Acid Synthase Polymorphisms, Tumor Expression, Body Mass Index, Prostate Cancer Risk, and Survival

    Science.gov (United States)

    Nguyen, Paul L.; Ma, Jing; Chavarro, Jorge E.; Freedman, Matthew L.; Lis, Rosina; Fedele, Giuseppe; Fiore, Christopher; Qiu, Weiliang; Fiorentino, Michelangelo; Finn, Stephen; Penney, Kathryn L.; Eisenstein, Anna; Schumacher, Fredrick R.; Mucci, Lorelei A.; Stampfer, Meir J.; Giovannucci, Edward; Loda, Massimo

    2010-01-01

    Purpose Fatty acid synthase (FASN) regulates de novo lipogenesis, body weight, and tumor growth. We examined whether common germline single nucleotide polymorphisms (SNPs) in the FASN gene affect prostate cancer (PCa) risk or PCa-specific mortality and whether these effects vary by body mass index (BMI). Methods In a prospective nested case-control study of 1,331 white patients with PCa and 1,267 age-matched controls, we examined associations of five common SNPs within FASN (and 5 kb upstream/downstream, R2 > 0.8) with PCa incidence and, among patients, PCa-specific death and tested for an interaction with BMI. Survival analyses were repeated for tumor FASN expression (n = 909). Results Four of the five SNPs were associated with lethal PCa. SNP rs1127678 was significantly related to higher BMI and interacted with BMI for both PCa risk (Pinteraction = .004) and PCa mortality (Pinteraction = .056). Among overweight men (BMI ≥ 25 kg/m2), but not leaner men, the homozygous variant allele carried a relative risk of advanced PCa of 2.49 (95% CI, 1.00 to 6.23) compared with lean men with the wild type. Overweight patients carrying the variant allele had a 2.04 (95% CI, 1.31 to 3.17) times higher risk of PCa mortality. Similarly, overweight patients with elevated tumor FASN expression had a 2.73 (95% CI, 1.05 to 7.08) times h