Prostaglandin synthesis and catabolism in the gastric mucosa: studies in normal rabbits and rabbits immunized with prostaglandin E2

International Nuclear Information System (INIS)

Redfern, J.S.

1988-01-01

Antral and fundic mucosal homogenates obtained from prostaglandin E2-immunized rabbits converted 14C-arachidonic acid to prostaglandin E2, 6-keto prostaglandin F1 alpha, prostaglandin F2 alpha, and prostaglandin D2. Percentage conversion of 14C-arachidonic acid to these prostaglandin products was not significantly different in prostaglandin E2-immunized rabbits compared with control rabbits (thyroglobulin-immunized and unimmunized rabbits combined). Synthesis of 6-keto prostaglandin F1 alpha, prostaglandin E2 and 13,14-dihydro 15-keto prostaglandin E2 from endogenous arachidonic acid after vortex mixing fundic mucosal homogenates was similar in prostaglandin E2 immunized rabbits and control rabbits. Both in prostaglandin E2-immunized rabbits and controls, 3H-prostaglandin E2 was catabolized extensively by the fundic mucosa, whereas 3H-6-keto prostaglandin F1 alpha, 3H-prostaglandin F2 alpha, and 3H-prostaglandin D2 were not catabolized to any appreciable extent. The rate of catabolism of PGs was not significantly different in prostaglandin E2-immunized rabbits and control rabbits, with the exception of prostaglandin F2 alpha which was catabolized slightly more rapidly in prostaglandin E2-immunized rabbits. These results indicate that development of gastric ulcers in prostaglandin E2-immunized rabbits is not associated with an alteration in the capacity of the gastric mucosa to synthesize or catabolize prostaglandins

Poly (ADP-ribose) catabolism in mammalian cells exposed to DNA-damaging agents

International Nuclear Information System (INIS)

Alvarez-Gonzalez, R.; Althaus, F.R.

1989-01-01

DNA damage inflicted by the alkylating agens N-methyl-N-nitro-N-nitrosoquanidine, or by UV stimulated the catabolism of protein-bound poly (ADP-ribose) in the chromatin of cultured hepatocytes. The stimulation was highest at the largest doses of DNA-damaging treatment. As a consequence, the half-life of ADP-ribosyl polymers may drop to less than 41 s. This rapid turnover contrasts with the slow catabolism of a constitutive fraction of polymers exhibiting a half-life of 7.7 h. These data suggest that post-incisional stimulation of poly (ADP-ribose) biosynthesis in DNA-excision repair is coupled with an adaptation of poly (ADP-ribose) catabolism in mammalian cells. (Author). 37 refs.; 3 figs

ProNormz--an integrated approach for human proteins and protein kinases normalization.

Science.gov (United States)

Subramani, Suresh; Raja, Kalpana; Natarajan, Jeyakumar

2014-02-01

The task of recognizing and normalizing protein name mentions in biomedical literature is a challenging task and important for text mining applications such as protein-protein interactions, pathway reconstruction and many more. In this paper, we present ProNormz, an integrated approach for human proteins (HPs) tagging and normalization. In Homo sapiens, a greater number of biological processes are regulated by a large human gene family called protein kinases by post translational phosphorylation. Recognition and normalization of human protein kinases (HPKs) is considered to be important for the extraction of the underlying information on its regulatory mechanism from biomedical literature. ProNormz distinguishes HPKs from other HPs besides tagging and normalization. To our knowledge, ProNormz is the first normalization system available to distinguish HPKs from other HPs in addition to gene normalization task. ProNormz incorporates a specialized synonyms dictionary for human proteins and protein kinases, a set of 15 string matching rules and a disambiguation module to achieve the normalization. Experimental results on benchmark BioCreative II training and test datasets show that our integrated approach achieve a fairly good performance and outperforms more sophisticated semantic similarity and disambiguation systems presented in BioCreative II GN task. As a freely available web tool, ProNormz is useful to developers as extensible gene normalization implementation, to researchers as a standard for comparing their innovative techniques, and to biologists for normalization and categorization of HPs and HPKs mentions in biomedical literature. URL: http://www.biominingbu.org/pronormz. Copyright © 2013 Elsevier Inc. All rights reserved.

Catabolism of (+/-)-abscisic acid by excised leaves of Hordeum vulgare L. cv Dyan and its modification by chemical and environmental factors

International Nuclear Information System (INIS)

Cowan, A.K.; Railton, I.D.

1987-01-01

Excised light-grown leaves and etiolated leaves of Hordeum vulgare L. cv Dyan catabolized applied (+/-)-[2- 14 C]abscisic acid ([+/-]-[2- 14 C]ABA) to phaseic acid (PA), dihydrophaseic acid (DPA), and 2'-hydroxymethyl ABA (2'-HMABA). Identification of these catabolites was made by microchemical methods and by combined capillary gas chromatography-mass spectrometry (GC-MS) following high dose feeds of nonlabeled substrate to leaves. Circular dichroism analysis revealed that 2'-HMABA was derived from the (-) enantiomer of ABA. Refeeding studies were used to confirm the catabolic route. The methyl ester of (+/-)-[2 14 C]-ABA was hydrolyzed efficiently by light-grown leaves of H. vulgare. Leaf age played a significant role in (+/-)-ABA catabolism, with younger leaves being less able than their older counterparts to catabolize this compound. The catabolism of (+/-)-ABA was inhibited markedly in water-stressed Hordeum leaves which was characterized by a decreased incorporation of label into 2'-HMABA, DPA, and conjugates. The specific, mixed function oxidase inhibitor, ancymidol, did not inhibit, dramatically (+/-)-ABA catabolism in light-grown leaves of Hordeum whereas the 80s ribosome, translational inhibitor, cycloheximide, inhibited this process markedly. The 70s ribosome translational inhibitors, lincomycin and chloramphenicol, were less effective than cycloheximide in inhibiting (+/-)-ABA catabolism, implying that cytoplasmic protein synthesis is necessary for the catabolism of (+/-)-ABA in Hordeum leaves whereas chloroplast protein synthesis plays only a minor role. This further suggests that the enzymes involved in (+/-)-ABA catabolism in this plant are cytoplasmically synthesized and are turned-over rapidly, although the enzyme responsible for glycosylating (+/-)-ABA itself appeared to be stable

Increased fat catabolism sustains water balance during fasting in zebra finches.

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Rutkowska, Joanna; Sadowska, Edyta T; Cichoń, Mariusz; Bauchinger, Ulf

2016-09-01

Patterns of physiological flexibility in response to fasting are well established, but much less is known about the contribution of water deprivation to the observed effects. We investigated body composition and energy and water budget in three groups of zebra finches: birds with access to food and water, food-deprived birds having access to drinking water and food-and-water-deprived birds. Animals were not stimulated by elevated energy expenditure and they were in thermoneutral conditions; thus, based on previous studies, water balance of fasting birds was expected to be maintained by increased catabolism of proteins. In contrast to this expectation, we found that access to water did not prevent reduction of proteinaceous tissue, but it saved fat reserves of the fasting birds. Thus, water balance of birds fasting without access to water seemed to be maintained by elevated fat catabolism, which generated 6 times more metabolic water compared with that in birds that had access to water. Therefore, we revise currently established views and propose fat to serve as the primary source for metabolic water production. Previously assumed increased protein breakdown for maintenance of water budget would occur if fat stores were depleted or if fat catabolism reached its upper limits due to high energy demands. © 2016. Published by The Company of Biologists Ltd.

Mitochondrial NUDIX hydrolases: A metabolic link between NAD catabolism, GTP and mitochondrial dynamics.

Science.gov (United States)

Long, Aaron; Klimova, Nina; Kristian, Tibor

2017-10-01

NAD + catabolism and mitochondrial dynamics are important parts of normal mitochondrial function and are both reported to be disrupted in aging, neurodegenerative diseases, and acute brain injury. While both processes have been extensively studied there has been little reported on how the mechanisms of these two processes are linked. This review focuses on how downstream NAD + catabolism via NUDIX hydrolases affects mitochondrial dynamics under pathologic conditions. Additionally, several potential targets in mitochondrial dysfunction and fragmentation are discussed, including the roles of mitochondrial poly(ADP-ribose) polymerase 1(mtPARP1), AMPK, AMP, and intra-mitochondrial GTP metabolism. Mitochondrial and cytosolic NUDIX hydrolases (NUDT9α and NUDT9β) can affect mitochondrial and cellular AMP levels by hydrolyzing ADP- ribose (ADPr) and subsequently altering the levels of GTP and ATP. Poly (ADP-ribose) polymerase 1 (PARP1) is activated after DNA damage, which depletes NAD + pools and results in the PARylation of nuclear and mitochondrial proteins. In the mitochondria, ADP-ribosyl hydrolase-3 (ARH3) hydrolyzes PAR to ADPr, while NUDT9α metabolizes ADPr to AMP. Elevated AMP levels have been reported to reduce mitochondrial ATP production by inhibiting the adenine nucleotide translocase (ANT), allosterically activating AMPK by altering the cellular AMP: ATP ratio, and by depleting mitochondrial GTP pools by being phosphorylated by adenylate kinase 3 (AK3), which uses GTP as a phosphate donor. Recently, activated AMPK was reported to phosphorylate mitochondria fission factor (MFF), which increases Drp1 localization to the mitochondria and promotes mitochondrial fission. Moreover, the increased AK3 activity could deplete mitochondrial GTP pools and possibly inhibit normal activity of GTP-dependent fusion enzymes, thus altering mitochondrial dynamics. Published by Elsevier Ltd.

Human serum albumin homeostasis: a new look at the roles of synthesis, catabolism, renal and gastrointestinal excretion, and the clinical value of serum albumin measurements

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Levitt DG

2016-07-01

Full Text Available David G Levitt,1,* Michael D Levitt2,* 1Department of Integrative Biology and Physiology, University of Minnesota, 2Research Service, Veterans Affairs Medical Center, Minneapolis, MN, USA *These authors contributed equally to this work Abstract: Serum albumin concentration (CP is a remarkably strong prognostic indicator of morbidity and mortality in both sick and seemingly healthy subjects. Surprisingly, the specifics of the pathophysiology underlying the relationship between CP and ill-health are poorly understood. This review provides a summary that is not previously available in the literature, concerning how synthesis, catabolism, and renal and gastrointestinal clearance of albumin interact to bring about albumin homeostasis, with a focus on the clinical factors that influence this homeostasis. In normal humans, the albumin turnover time of about 25 days reflects a liver albumin synthesis rate of about 10.5 g/day balanced by renal (≈6%, gastrointestinal (≈10%, and catabolic (≈84% clearances. The acute development of hypoalbuminemia with sepsis or trauma results from increased albumin capillary permeability leading to redistribution of albumin from the vascular to interstitial space. The best understood mechanism of chronic hypoalbuminemia is the decreased albumin synthesis observed in liver disease. Decreased albumin production also accounts for hypoalbuminemia observed with a low-protein and normal caloric diet. However, a calorie- and protein-deficient diet does not reduce albumin synthesis and is not associated with hypoalbuminemia, and CP is not a useful marker of malnutrition. In most disease states other than liver disease, albumin synthesis is normal or increased, and hypoalbuminemia reflects an enhanced rate of albumin turnover resulting either from an increased rate of catabolism (a poorly understood phenomenon or enhanced loss of albumin into the urine (nephrosis or intestine (protein-losing enteropathy. The latter may occur

Influence of high glycine diets on the activity of glycine-catabolizing enzymes and on glycine catabolism in rats

International Nuclear Information System (INIS)

Petzke, K.J.; Albrecht, V.; Przybilski, H.

1986-01-01

Male albino rats were adapted to isocaloric purified diets that differed mainly in their glycine and casein contents. Controls received a 30% casein diet. In experimental diets gelatin or gelatin hydrolysate was substituted for half of the 30% casein. An additional group was fed a glycine-supplemented diet, which corresponded in glycine level to the gelatin diet but in which the protein level was nearly the same as that of the casein control diet. Another group received a 15% casein diet. Rat liver glycine cleavage system, serine hydroxymethyltransferase and serine dehydratase activities were measured. 14 CO 2 production from the catabolism of 14 C-labeled glycine was measured in vivo and in vitro (from isolated hepatocytes). Serine dehydratase and glycine cleavage system activities were higher in animals fed 30% casein diets than in those fed 15% casein diets. Serine hydroxymethyltransferase activity of the cytosolic and mitochondrial fractions was highest when a high glycine diet (glycine administered as pure, protein bound in gelatin or peptide bound in gelatin hydrolysate) was fed. 14 CO 2 formation from [1- 14 C]- and [2- 14 C]glycine both in vivo and in isolated hepatocytes was higher when a high glycine diet was fed than when a casein diet was fed. These results suggest that glycine catabolism is dependent on and adaptable to the glycine content of the diet. Serine hydroxymethyltransferase appears to play a major role in the regulation of glycine degradation via serine and pyruvate

A metabolic pathway for catabolizing levulinic acid in bacteria

International Nuclear Information System (INIS)

Rand, Jacqueline M.; Pisithkul, Tippapha; Clark, Ryan L.; Thiede, Joshua M.; Mehrer, Christopher R.

2017-01-01

Microorganisms can catabolize a wide range of organic compounds and therefore have the potential to perform many industrially relevant bioconversions. One barrier to realizing the potential of biorefining strategies lies in our incomplete knowledge of metabolic pathways, including those that can be used to assimilate naturally abundant or easily generated feedstocks. For instance, levulinic acid (LA) is a carbon source that is readily obtainable as a dehydration product of lignocellulosic biomass and can serve as the sole carbon source for some bacteria. Yet, the genetics and structure of LA catabolism have remained unknown. Here, we report the identification and characterization of a seven-gene operon that enables LA catabolism in Pseudomonas putida KT2440. When the pathway was reconstituted with purified proteins, we observed the formation of four acyl-CoA intermediates, including a unique 4-phosphovaleryl-CoA and the previously observed 3-hydroxyvaleryl-CoA product. Using adaptive evolution, we obtained a mutant of Escherichia coli LS5218 with functional deletions of fadE and atoC that was capable of robust growth on LA when it expressed the five enzymes from the P. putida operon. Here, this discovery will enable more efficient use of biomass hydrolysates and metabolic engineering to develop bioconversions using LA as a feedstock.

Participation of the arcRACME protein in self-activation of the arc operon located in the arginine catabolism mobile element in pandemic clone USA300.

Science.gov (United States)

Rozo, Zayda Lorena Corredor; Márquez-Ortiz, Ricaurte Alejandro; Castro, Betsy Esperanza; Gómez, Natasha Vanegas; Escobar-Pérez, Javier

2017-07-01

Staphylococcus aureus pandemic clone USA300 has, in addition to its constitutive arginine catabolism (arc) gene cluster, an arginine catabolism mobile element (ACME) carrying another such cluster, which gives this clone advantages in colonisation and infection. Gene arcR, which encodes an oxygen-sensitive transcriptional regulator, is inside ACME and downstream of the constitutive arc gene cluster, and this situation may have an impact on its activation. Different relative expression behaviours are proven here for arcRACME and the arcACME operon compared to the constitutive ones. We also show that the artificially expressed recombinant ArcRACME protein binds to the promoter region of the arcACME operon; this mechanism can be related to a positive feedback model, which may be responsible for increased anaerobic survival of the USA300 clone during infection-related processes.

Activation of endoplasmic reticulum stress response by enhanced polyamine catabolism is important in the mediation of cisplatin-induced acute kidney injury.

Directory of Open Access Journals (Sweden)

Kamyar Zahedi

Full Text Available Cisplatin-induced nephrotoxicity limits its use in many cancer patients. The expression of enzymes involved in polyamine catabolism, spermidine/spermine N1-acetyltransferase (SSAT and spermine oxidase (SMOX increase in the kidneys of mice treated with cisplatin. We hypothesized that enhanced polyamine catabolism contributes to tissue damage in cisplatin acute kidney injury (AKI. Using gene knockout and chemical inhibitors, the role of polyamine catabolism in cisplatin AKI was examined. Deficiency of SSAT, SMOX or neutralization of the toxic products of polyamine degradation, H2O2 and aminopropanal, significantly diminished the severity of cisplatin AKI. In vitro studies demonstrated that the induction of SSAT and elevated polyamine catabolism in cells increases the phosphorylation of eukaryotic translation initiation factor 2α (eIF2α and enhances the expression of binding immunoglobulin protein BiP/GRP78 and CCAAT-enhancer-binding protein homologous protein (CHOP/GADD153. The increased expression of these endoplasmic reticulum stress response (ERSR markers was accompanied by the activation of caspase-3. These results suggest that enhanced polyamine degradation in cisplatin AKI may lead to tubular damage through the induction of ERSR and the consequent onset of apoptosis. In support of the above, we show that the ablation of the SSAT or SMOX gene, as well as the neutralization of polyamine catabolism products modulate the onset of ERSR (e.g. lower BiP and CHOP and apoptosis (e.g. reduced activated caspase-3. These studies indicate that enhanced polyamine catabolism and its toxic products are important mediators of ERSR and critical to the pathogenesis of cisplatin AKI.

Loci of catabolism of beta-very low density lipoprotein in vivo delineated with a residualizing label, 125I-dilactitol tyramine

International Nuclear Information System (INIS)

Daugherty, A.; Thorpe, S.R.; Lange, L.G.; Sobel, B.E.; Schonfeld, G.

1985-01-01

beta-Very low density lipoprotein (beta-VLDL) may be a major atherogenic lipoprotein, and knowledge of the sites of its catabolism should facilitate elucidation of mechanisms important in the regulation of its plasma concentrations. In this study, catabolic sites of beta-VLDL have been delineated in normolipidemic rabbits with a novel, radioiodinated, residualizing label, 125 I-dilactitol tyramine ( 125 I-DLT). Comparative studies of beta-VLDL and low density lipoprotein catabolism were performed with 125 I-DLT conjugated to each lipoprotein and with lipoproteins iodine-labeled conventionally. Conjugation did not alter size distributions or charge characteristics of lipoprotein particles. The overall processing (binding and degradation) of lipoproteins by cultured rabbit skin fibroblasts was not influenced by 125 I-DLT derivatization, suggesting that attachment of the label did not influence cell receptor-lipoprotein interactions. Furthermore, although degradation products of 125 I-lipoproteins leaked out of the cells and into the medium, the degradation products of 125 I-DLT lipoproteins were retained by the cells. The principal catabolic site of beta-VLDL in normolipidemic rabbits was found to be the liver with 54 +/- 4% of injected 125 I retained in this organ 24 h after injection of 125 I-DLT-beta-VLDL. When catabolism was normalized to tissue weight, the liver and adrenals were found to be approximately equally active in the metabolism of beta-VLDL. In agreement with results of other studies with residualizing labels, the principal organ of catabolism of 125 I-DLT-LDL in vivo was the liver. The adrenals were the most highly catabolizing organ when results were normalized for tissue weight

Metabolic control analysis of xylose catabolism in Aspergillus

NARCIS (Netherlands)

Prathumpai, W.; Gabelgaard, J.B.; Wanchanthuek, P.; Vondervoort, van de P.J.I.; Groot, de M.J.L.; McIntyre, M.; Nielsen, J.

2003-01-01

A kinetic model for xylose catabolism in Aspergillus is proposed. From a thermodynamic analysis it was found that the intermediate xylitol will accumulate during xylose catabolism. Use of the kinetic model allowed metabolic control analysis (MCA) of the xylose catabolic pathway to be carried out,

SwarmDock and the Use of Normal Modes in Protein-Protein Docking

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Paul A. Bates

2010-09-01

Full Text Available Here is presented an investigation of the use of normal modes in protein-protein docking, both in theory and in practice. Upper limits of the ability of normal modes to capture the unbound to bound conformational change are calculated on a large test set, with particular focus on the binding interface, the subset of residues from which the binding energy is calculated. Further, the SwarmDock algorithm is presented, to demonstrate that the modelling of conformational change as a linear combination of normal modes is an effective method of modelling flexibility in protein-protein docking.

Formation of Flavor Compounds by Amino Acid Catabolism in Cheese (Turkish with English Abstract

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2015-02-01

Full Text Available Biochemical reactions which contribute flavor formation occur in result of proteolysis during cheese ripening. Casein as the main protein of cheese has a significant effect on the flavor and textural properties of cheeses via its degradation to small peptides and free amino acids by various factors like coagulant enzymes. Specific flavors of cheeses occur as a result of amino acid catabolism by starter and non-starter bacteria. Some flavor compounds are formed by enzymatic transformations as well as by non-enzymatic, chemical changes in cheese. In this paper, formation of flavor compounds by amino acid catabolism during cheese ripening reviewed.

Metabolic signature of sun exposed skin suggests catabolic pathway overweighs anabolic pathway.

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Manpreet Randhawa

Full Text Available Skin chronically exposed to sun results in phenotypic changes referred as photoaging. This aspect of aging has been studied extensively through genomic and proteomic tools. Metabolites, the end product are generated as a result of biochemical reactions are often studied as a culmination of complex interplay of gene and protein expression. In this study, we focused exclusively on the metabolome to study effects from sun-exposed and sun-protected skin sites from 25 human subjects. We generated a highly accurate metabolomic signature for the skin that is exposed to sun. Biochemical pathway analysis from this data set showed that sun-exposed skin resides under high oxidative stress and the chains of reactions to produce these metabolites are inclined toward catabolism rather than anabolism. These catabolic activities persuade the skin cells to generate metabolites through the salvage pathway instead of de novo synthesis pathways. Metabolomic profile suggests catabolic pathways and reactive oxygen species operate in a feed forward fashion to alter the biology of sun exposed skin.

Normal mode-guided transition pathway generation in proteins.

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Byung Ho Lee

Full Text Available The biological function of proteins is closely related to its structural motion. For instance, structurally misfolded proteins do not function properly. Although we are able to experimentally obtain structural information on proteins, it is still challenging to capture their dynamics, such as transition processes. Therefore, we need a simulation method to predict the transition pathways of a protein in order to understand and study large functional deformations. Here, we present a new simulation method called normal mode-guided elastic network interpolation (NGENI that performs normal modes analysis iteratively to predict transition pathways of proteins. To be more specific, NGENI obtains displacement vectors that determine intermediate structures by interpolating the distance between two end-point conformations, similar to a morphing method called elastic network interpolation. However, the displacement vector is regarded as a linear combination of the normal mode vectors of each intermediate structure, in order to enhance the physical sense of the proposed pathways. As a result, we can generate more reasonable transition pathways geometrically and thermodynamically. By using not only all normal modes, but also in part using only the lowest normal modes, NGENI can still generate reasonable pathways for large deformations in proteins. This study shows that global protein transitions are dominated by collective motion, which means that a few lowest normal modes play an important role in this process. NGENI has considerable merit in terms of computational cost because it is possible to generate transition pathways by partial degrees of freedom, while conventional methods are not capable of this.

A model for the catabolism of rhizopine in Rhizobium leguminosarum involves a ferredoxin oxygenase complex and the inositol degradative pathway.

Science.gov (United States)

Bahar, M; de Majnik, J; Wexler, M; Fry, J; Poole, P S; Murphy, P J

1998-11-01

Rhizopines are nodule-specific compounds that confer an intraspecies competitive nodulation advantage to strains that can catabolize them. The rhizopine (3-O-methyl-scyllo-inosamine, 3-O-MSI) catabolic moc gene cluster mocCABRDE(F) in Rhizobium leguminosarum bv. viciae strain 1a is located on the Sym plasmid. MocCABR are homologous to the mocCABR gene products from Sinorhizobium meliloti. MocD and MocE contain motifs corresponding to a TOL-like oxygenase and a [2Fe-2S] Rieske-like ferredoxin, respectively. The mocF gene encodes a ferredoxin reductase that would complete the oxygenase system, but is not essential for rhizopine catabolism. We propose a rhizopine catabolic model whereby MocB transports rhizopine into the cell and MocDE and MocF (or a similar protein elsewhere in the genome), under the regulation of MocR, act in concert to form a ferredoxin oxygenase system that demethylates 3-O-MSI to form scyllo-inosamine (SI). MocA, an NAD(H)-dependent dehydrogenase, and MocC continue the catabolic process. Compounds formed then enter the inositol catabolic pathway.

Effects of lipopolysaccharide on the catabolic activity of macrophages

International Nuclear Information System (INIS)

Cluff, C.; Ziegler, H.K.

1986-01-01

The ability of macrophages to degrade and catabolize antigens is of relevance both as a means to process complex antigens prior to presentation to T cells, as well as a way to down regulate immune responses by destroying the antigenicity of polypeptides. With these considerations, the authors have investigated the regulation of macrophage catabolic activity by lipopolysaccharide (LPS). Catabolic activity was quantitated by following the distribution and molecular form of 125 -I labelled surface components of heat-killed Listeria monocytogenes (HKLM) subsequent to their uptake by macrophages. They have compared the catabolic activity of macrophages from peritoneal exudates of mice injected i.p. with saline or LPS and have found that LPS-elicited macrophages display a greatly enhanced (3 fold) rate of catabolism. This increase in catabolic activity peaks 3 days after LPS injection and steadily declines thereafter, approaching a baseline level after 3 weeks. The enhancement of catabolic activity is under LPS gene control. LPS-elicited macrophages rapidly destroy the antigenicity of bacterial antigens and function poorly as antigen presenting cells in vitro. These results suggest that LPS elicits a macrophage population specialized for antigen degradation functions with negative regulatory effects on the induction of specific immune responses

Lactoferricin mediates anabolic and anti-catabolic effects in the intervertebral disc.

Science.gov (United States)

Kim, Jae-Sung; Ellman, Michael B; An, Howard S; Yan, Dongyao; van Wijnen, Andre J; Murphy, Gillian; Hoskin, David W; Im, Hee-Jeong

2012-04-01

Lactoferricin (LfcinB) antagonizes biological effects mediated by angiogenic and catabolic growth factors, in addition to pro-inflammatory cytokines and chemokines in human endothelial cells and tumor cells. However, the effect of LfcinB on intervertebral disc (IVD) cell metabolism has not yet been investigated. Using bovine nucleus pulposus (NP) cells, we analyzed the effect of LfcinB on proteoglycan (PG) accumulation, PG synthesis, and anabolic gene expression. We assessed expression of genes for matrix-degrading enzymes such as matrix metalloproteases (MMPs) and a disintegrin-like and metalloprotease with thrombospondin motifs (ADAMTS family), as well as their endogenous inhibitors, tissue inhibitor of metalloproteases (TIMPs). In order to understand the specific molecular mechanisms by which LfcinB exerts its biological effects, we investigated intracellular signaling pathways in NP cells. LfcinB increased PG accumulation mainly via PG synthesis in a dose-dependent manner. Simultaneously, LfcinB dose-dependently downregulated catabolic enzymes. LfcinB's anti-catabolic effects were further demonstrated by a dose-dependent increase in multiple TIMP family members. Our results demonstrate that ERK and/or p38 mitogen-activated protein kinase pathways are the key signaling cascades that exert the biological effects of LfcinB in NP cells, regulating transcription of aggrecan, SOX-9, TIMP-1, TIMP-2, TIMP-3, and iNOS. Our results suggest that LfcinB has anabolic and potent anti-catabolic biological effects on bovine IVD cells that may have considerable promise in the treatment of disc degeneration in the future. Copyright © 2011 Wiley Periodicals, Inc.

O-(4-diazo-3,5-di[125I]iodobenzoyl)sucrose, a novel radioactive label for determining organ sites of catabolism of plasma proteins

International Nuclear Information System (INIS)

Jong, A.S.H. de; Bouma, J.M.W.; Gruber, M.

1981-01-01

A method is described for radiolabelling proteins with O-(4-diazo-3,5-di[ 125 I]iodobenzoyl)sucrose (DD 125 IBS). When proteins so labelled were degraded within lysosomes, the radioactive fragments were largely retained within the organelle. High specific radioactivities were obtained without changing the properties of the protein. The validity of the method was demonstrated in vivo in rats using the short-lived protein lactate dehydrogenase, isoenzyme M 4 , and the long-lived protein bovine serum albumin. Derivatization with DD 125 IBS did not alter the clearance of either protein. Uptake of DD 125 IBS-labelled lactate dehydrogenase, isoenzyme M 4 , by liver and spleen of rats was determined. Radioactivity in these tissues increased up to about 2 h after injection (at this time the protein has been almost completely cleared from the blood) and subsequently declined with a half-life of approx. 20h. After differential fractionation of liver, radioactivity was largely found in the mitochondrial and lysosomal fraction. The results of these studies establish that DD 125 IBS covalently coupled to plasma proteins should be a useful radioactive tracer for identifying the tissue and cellular sites of catabolism of relatively long-lived circulating proteins. (author)

Role of growth hormone, insulin-like growth factor-I, and insulin-like growth factor binding proteins in the catabolic response to injury and infection.

Science.gov (United States)

Lang, Charles H; Frost, Robert A

2002-05-01

The erosion of lean body mass resulting from protracted critical illness remains a significant risk factor for increased morbidity and mortality in this patient population. Previous studies have documented the well known impairment in nitrogen balance results from both an increase in muscle protein degradation as well as a decreased rate of both myofibrillar and sacroplasmic protein synthesis. This protein imbalance may be caused by an increased presence or activity of various catabolic agents, such as tumor necrosis factor-alpha, interleukin-1 beta, interleukin-6 or glucocorticoids, or may be mediated via a decreased concentration or responsiveness to various anabolic hormones, such as growth hormone or insulin-like growth factor-I. This review focuses on recent developments pertaining to the importance of alterations in the growth hormone-insulin-like growth factor-I axis as a mechanism for the observed defects in muscle protein balance.

Cy5 total protein normalization in Western blot analysis.

Science.gov (United States)

Hagner-McWhirter, Åsa; Laurin, Ylva; Larsson, Anita; Bjerneld, Erik J; Rönn, Ola

2015-10-01

Western blotting is a widely used method for analyzing specific target proteins in complex protein samples. Housekeeping proteins are often used for normalization to correct for uneven sample loads, but these require careful validation since expression levels may vary with cell type and treatment. We present a new, more reliable method for normalization using Cy5-prelabeled total protein as a loading control. We used a prelabeling protocol based on Cy5 N-hydroxysuccinimide ester labeling that produces a linear signal response. We obtained a low coefficient of variation (CV) of 7% between the ratio of extracellular signal-regulated kinase (ERK1/2) target to Cy5 total protein control signals over the whole loading range from 2.5 to 20.0μg of Chinese hamster ovary cell lysate protein. Corresponding experiments using actin or tubulin as controls for normalization resulted in CVs of 13 and 18%, respectively. Glyceraldehyde-3-phosphate dehydrogenase did not produce a proportional signal and was not suitable for normalization in these cells. A comparison of ERK1/2 signals from labeled and unlabeled samples showed that Cy5 prelabeling did not affect antibody binding. By using total protein normalization we analyzed PP2A and Smad2/3 levels with high confidence. Copyright © 2015 Elsevier Inc. All rights reserved.

Metabolism and catabolism in hip fracture patients: nutritional and anabolic intervention--a review.

Science.gov (United States)

Hedström, Margareta; Ljungqvist, Olle; Cederholm, Tommy

2006-10-01

Patients suffering from hip fracture are known to be at risk of catabolism and protein-energy malnutrition. In this review we discuss the pathogenesis of hip fracture-related catabolism per- and postoperatively. We also describe the consequences of malnutrition after a hip fracture and summarize studies that have evaluated the effect of nutritional or anabolic treatment of these patients. There has been relatively little published on the effects of nutritional and anabolic pharmacological interventions for improvement of nutritional status and on the role of nutritional status in clinical outcomes. Even so, there have been 19 randomized studies in this field. 12 studies evaluated nutritional supplementation or protein supplementation. 6 found improved clinical outcome with fewer complications, faster recovery and shorter length of hospital stay, whereas the others reported no difference in clinical outcome. For pharmacological interventions, the outcomes have been even less clear. Supplementation studies in general appear to be underpowered or suffer logistic problems. Studies of higher scientific quality are needed, and enteral feeding, anabolic treatment and multimodal approaches need to be evaluated in greater depth.

Thioacetamide effects on protein metabolism in the liver: lessons from isolated hepatocytes

International Nuclear Information System (INIS)

Cajone, F.; Bernelli-Zazzera, A.

1984-01-01

The effects of a short-term treatment with thioacetamide have been studied in isolated hepatocytes obtained from intoxicated rats. A technique has been developed which utilizes leucine alternatively labeled with either [ 14 C] or [ 3 H] and permits the simultaneous evaluation of protein synthesis, catabolism and secretion in the same cell during the same incubation period. The results indicate that short-term thioacetamide treatment causes an overall slowing-down of protein metabolism. Protein synthesis, however, decreases less than protein degradation and total protein secretion; albumin secretion, which is also less than normal, seems to be less compromised than total protein secretion

Studying Catabolism of Protein ADP-Ribosylation.

Science.gov (United States)

Palazzo, Luca; James, Dominic I; Waddell, Ian D; Ahel, Ivan

2017-01-01

Protein ADP-ribosylation is a conserved posttranslational modification that regulates many major cellular functions, such as DNA repair, transcription, translation, signal transduction, stress response, cell division, aging, and cell death. Protein ADP-ribosyl transferases catalyze the transfer of an ADP-ribose (ADPr) group from the β-nicotinamide adenine dinucleotide (β-NAD + ) cofactor onto a specific target protein with the subsequent release of nicotinamide. ADP-ribosylation leads to changes in protein structure, function, stability, and localization, thus defining the appropriate cellular response. Signaling processes that are mediated by modifications need to be finely tuned and eventually silenced and one of the ways to achieve this is through the action of enzymes that remove (reverse) protein ADP-ribosylation in a timely fashion such as PARG, TARG1, MACROD1, and MACROD2. Here, we describe several basic methods used to study the enzymatic activity of de-ADP-ribosylating enzymes.

Convergent evolution of Amadori opine catabolic systems in plasmids of Agrobacterium tumefaciens.

Science.gov (United States)

Baek, Chang-Ho; Farrand, Stephen K; Lee, Ko-Eun; Park, Dae-Kyun; Lee, Jeong Kug; Kim, Kun-Soo

2003-01-01

Deoxyfructosyl glutamine (DFG, referred to elsewhere as dfg) is a naturally occurring Amadori compound found in rotting fruits and vegetables. DFG also is an opine and is found in tumors induced by chrysopine-type strains of Agrobacterium tumefaciens. Such strains catabolize this opine via a pathway coded for by their plasmids. NT1, a derivative of the nopaline-type A. tumefaciens strain C58 lacking pTiC58, can utilize DFG as the sole carbon source. Genes for utilization of DFG were mapped to the 543-kb accessory plasmid pAtC58. Two cosmid clones of pAtC58 allowed UIA5, a plasmid-free derivative of C58, harboring pSa-C that expresses MocC (mannopine [MOP] oxidoreductase that oxidizes MOP to DFG), to grow by using MOP as the sole carbon source. Genetic analysis of subclones indicated that the genes for utilization of DFG are located in a 6.2-kb BglII (Bg2) region adjacent to repABC-type genes probably responsible for the replication of pAtC58. This region contains five open reading frames organized into at least two transcriptional soc (santhopine catabolism) groups: socR and socABCD. Nucleotide sequence analysis and analyses of transposon-insertion mutations in the region showed that SocR negatively regulates the expression of socR itself and socABCD. SocA and SocB are responsible for transport of DFG and MOP. SocA is a homolog of known periplasmic amino acid binding proteins. The N-terminal half of SocB is a homolog of the transmembrane transporter proteins for several amino acids, and the C-terminal half is a homolog of the transporter-associated ATP-binding proteins. SocC and SocD could be responsible for the enzymatic degradation of DFG, being homologs of sugar oxidoreductases and an amadoriase from Corynebacterium sp., respectively. The protein products of socABCD are not related at the amino acid sequence level to those of the moc and mot genes of Ti plasmids responsible for utilization of DFG and MOP, indicating that these two sets of genes and their

Tissue protein metabolism in parasitized animals

International Nuclear Information System (INIS)

Symons, L.E.A.; Steel, J.W.; Jones, W.O.

1981-01-01

The effects of gastrointestinal nematode infection of mammals, particularly of the small intestine of the sheep, on protein metabolism of skeletal muscle, liver, the gastrointestinal tract and wool are described. These changes have been integrated to explain poor growth and production in the sheep heavily infected with Trichostrongylus colubriformis. The rates of both synthesis and catabolism of muscle protein are depressed, but nitrogen is lost from this tissue because the depression of synthesis exceeds that of catabolism. Anorexia is the major cause of these changes. Although the effect on liver protein synthesis is unclear, it is probable that the leakage of plasma proteins into the gastrointestinal tract stimulates an early increase in the rate of synthesis of these proteins, but this eventually declines and is insufficient to correct developing hypoalbuminaemia. Changes in the intestinal tract are complex. Exogenous nitrogen is reduced by anorexia, but the flow of nitrogen through the tract from abomasum to faeces is above normal because of the increase of endogenous protein from leakage of plasma protein and, presumably, from exfoliated epithelial cells. There is evidence that protein metabolism of intestinal tissue, particularly in the uninfected distal two-thirds, is increased. Synthesis of wool protein is decreased. As the result of anorexia, intestinal loss of endogenous protein and an increased rate of intestinal protein metabolism there is a net movement of amino nitrogen from muscle, liver and possibly skin to the intestine of the heavily infected sheep. Thus, the availability of amino nitrogen for growth and wool production is reduced. (author)

Glutamine alimentation in catabolic state.

Science.gov (United States)

Boelens, P G; Nijveldt, R J; Houdijk, A P; Meijer, S; van Leeuwen, P A

2001-09-01

Glutamine should be reclassified as a conditionally essential amino acid in the catabolic state because the body's glutamine expenditures exceed synthesis and low glutamine levels in plasma are associated with poor clinical outcome. After severe stress, several amino acids are mobilized from muscle tissue to supply energy and substrate to the host. Glutamine is one of the most important amino acids that provide this function. Glutamine acts as the preferred respiratory fuel for lymphocytes, hepatocytes and intestinal mucosal cells and is metabolized in the gut to citrulline, ammonium and other amino acids. Low concentrations of glutamine in plasma reflect reduced stores in muscle and this reduced availability of glutamine in the catabolic state seems to correlate with increased morbidity and mortality. Adding glutamine to the nutrition of clinical patients, enterally or parenterally, may reduce morbidity. Several excellent clinical trials have been performed to prove efficacy and feasibility of the use of glutamine supplementation in parenteral and enteral nutrition. The increased intake of glutamine has resulted in lower septic morbidity in certain critically ill patient populations. This review will focus on the efficacy and the importance of glutamine supplementation in diverse catabolic states.

Inhibition of collagen production in scleroderma fibroblast cultures by a connective tissue glycoprotein extracted from normal dermis

International Nuclear Information System (INIS)

Maquart, F.X.; Bellon, G.; Cornillet-Stoupy, J.; Randoux, A.; Triller, R.; Kalis, B.; Borel, J.P.

1985-01-01

It was shown in a previous paper that a connective tissue glycoprotein (CTGP) extracted from normal rabbit dermis was able to inhibit total protein and collagen syntheses by normal dermis fibroblast cultures. In the present study, the effects of CTGP on scleroderma fibroblasts were investigated. [ 14 C]Proline incorporation into total proteins of the supernatant was not significantly different from that found in controls. By contrast, the amount of collagen, expressed as percentage of total secreted protein, was far higher in scleroderma cultures than in normal ones (14.4% +/- 6.0% vs 4.6% +/- 0.9%). Addition of CTGP to the medium induced a concentration-dependent inhibition of [ 14 C]proline incorporation into proteins from both control and scleroderma cells. In control cultures, no significant decrease of the percentage of collagen was observed, but over 60 micrograms/ml, both cytotoxic effects and inhibition of protein synthesis occurred. In scleroderma cultures, the inhibition was twice as effective on collagen as on noncollagen protein synthesis. The inhibition of collagen secretion was not related either to changes in collagen hydroxylation or to the intracellular catabolism of newly synthesized procollagen

Shared strategies for β-lactam catabolism in the soil microbiome

DEFF Research Database (Denmark)

Crofts, Terence S.; Wang, Bin; Spivak, Aaron

2018-01-01

The soil microbiome can produce, resist, or degrade antibiotics and even catabolize them. While resistance genes are widely distributed in the soil, there is a dearth of knowledge concerning antibiotic catabolism. Here we describe a pathway for penicillin catabolism in four isolates. Genomic......, respectively. Elucidation of additional pathways may allow bioremediation of antibiotic-contaminated soils and discovery of antibiotic-remodeling enzymes with industrial utility....

Pentose phosphates in nucleoside interconversion and catabolism.

Science.gov (United States)

Tozzi, Maria G; Camici, Marcella; Mascia, Laura; Sgarrella, Francesco; Ipata, Piero L

2006-03-01

Ribose phosphates are either synthesized through the oxidative branch of the pentose phosphate pathway, or are supplied by nucleoside phosphorylases. The two main pentose phosphates, ribose-5-phosphate and ribose-1-phosphate, are readily interconverted by the action of phosphopentomutase. Ribose-5-phosphate is the direct precursor of 5-phosphoribosyl-1-pyrophosphate, for both de novo and 'salvage' synthesis of nucleotides. Phosphorolysis of deoxyribonucleosides is the main source of deoxyribose phosphates, which are interconvertible, through the action of phosphopentomutase. The pentose moiety of all nucleosides can serve as a carbon and energy source. During the past decade, extensive advances have been made in elucidating the pathways by which the pentose phosphates, arising from nucleoside phosphorolysis, are either recycled, without opening of their furanosidic ring, or catabolized as a carbon and energy source. We review herein the experimental knowledge on the molecular mechanisms by which (a) ribose-1-phosphate, produced by purine nucleoside phosphorylase acting catabolically, is either anabolized for pyrimidine salvage and 5-fluorouracil activation, with uridine phosphorylase acting anabolically, or recycled for nucleoside and base interconversion; (b) the nucleosides can be regarded, both in bacteria and in eukaryotic cells, as carriers of sugars, that are made available though the action of nucleoside phosphorylases. In bacteria, catabolism of nucleosides, when suitable carbon and energy sources are not available, is accomplished by a battery of nucleoside transporters and of inducible catabolic enzymes for purine and pyrimidine nucleosides and for pentose phosphates. In eukaryotic cells, the modulation of pentose phosphate production by nucleoside catabolism seems to be affected by developmental and physiological factors on enzyme levels.

Protein Degradation in Normal and Beige (Chediak-Higashi) Mice

Science.gov (United States)

Lyons, Robert T.; Pitot, Henry C.

1978-01-01

The beige mouse, C57BL/6 (bg/bg), is an animal model for the Chediak-Higashi syndrome in man, a disease characterized morphologically by giant lysosomes in most cell types. Half-lives for the turnover of [14C]bicarbonate-labeled total soluble liver protein were determined in normal and beige mice. No significant differences were observed between the normal and mutant strain for both rapidly and slowly turning-over classes of proteins. Glucagon treatment during the time-course of protein degradation had similar effects on both normal and mutant strains and led to the conclusion that the rate of turnover of endogenous intracellular protein in the beige mouse liver does not differ from normal. The rates of uptake and degradation of an exogenous protein were determined in normal and beige mice by intravenously injecting 125I-bovine serum albumin and following, in peripheral blood, the loss with time of phosphotungstic acid-insoluble bovine serum albumin and the parallel appearance of phosphotungstic acid-soluble (degraded) material. No significant differences were observed between beige and normal mice in the uptake by liver lysosomes of 125I-bovine serum albumin (t½ = 3.9 and 2.8 h, respectively). However, it was found that lysosomes from livers of beige mice released phosphotungstic acid-soluble radioactivity at a rate significantly slower than normal (t½ = 6.8 and 3.1 h, respectively). This defect in beige mice could be corrected by chronic administration of carbamyl choline (t½ = 3.5 h), a cholinergic agonist which raises intracellular cyclic GMP levels. However, no significant differences between normal and beige mice were observed either in the ability of soluble extracts of liver and kidney to bind [3H]cyclic GMP in vitro or in the basal levels of cyclic AMP in both tissues. The relevance of these observations to the presumed biochemical defect underlying the Chediak-Higashi syndrome is discussed. PMID:202611

Administration of structured lipid composed of MCT and fish oil reduces net protein catabolism in enterally fed burned rats.

Science.gov (United States)

Teo, T C; DeMichele, S J; Selleck, K M; Babayan, V K; Blackburn, G L; Bistrian, B R

1989-01-01

The effects of enteral feeding with safflower oil or a structured lipid (SL) derived from 60% medium-chain triglyceride (MCT) and 40% fish oil (MCT/fish oil) on protein and energy metabolism were compared in gastrostomy-fed burned rats (30% body surface area) by measuring oxygen consumption, carbon dioxide production, nitrogen balance, total liver protein, whole-body leucine kinetics, and rectus muscle and liver protein fractional synthetic rates (FSR, %/day). Male Sprague-Dawley rats (195 +/- 5g) received 50 ml/day of an enteral regimen containing 50 kcal, 2 g amino acids, and 40% nonprotein calories as lipid for three days. Protein kinetics were estimated by using a continuous L-[1-14C] leucine infusion technique on day 2. Thermally injured rats enterally fed MCT/fish oil yielded significantly higher daily and cumulative nitrogen balances (p less than or equal to 0.025) and rectus muscle (39%) FSR (p less than or equal to 0.05) when compared with safflower oil. MCT/fish oil showed a 22% decrease (p less than or equal to 0.005) in per cent flux oxidized and a 7% (p less than or equal to 0.05) decrease in total energy expenditure (TEE) versus safflower oil. A 15% increase in liver FSR was accompanied by a significant elevation (p less than or equal to 0.025) in total liver protein with MCT/fish oil. This novel SL shares the properties of other structured lipids in that it reduces the net protein catabolic effects of burn injury, in part, by influencing tissue protein synthetic rates. The reduction in TEE is unique to MCT/fish oil and may relate to the ability of fish oil to diminish the injury response. PMID:2500898

The ygeW encoded protein from Escherichia coli is a knotted ancestral catabolic transcarbamylase

Energy Technology Data Exchange (ETDEWEB)

Li, Yongdong; Jin, Zhongmin; Yu, Xiaolin; Allewell, Norma M.; Tuchman, Mendel; Shi, Dashuang (Maryland); (GWU); (Georgia)

2012-06-28

Purine degradation plays an essential role in nitrogen metabolism in most organisms. Uric acid is the final product of purine catabolism in humans, anthropoid apes, birds, uricotelic reptiles, and almost all insects. Elevated levels of uric acid in blood (hyperuricemia) cause human diseases such as gout, kidney stones, and renal failure. Although no enzyme has been identified that further degrades uric acid in humans, it can be oxidized to produce allantoin by free-radical attack. Indeed, elevated levels of allantoin are found in patients with rheumatoid arthritis, chronic lung disease, bacterial meningitis, and noninsulin-dependent diabetes mellitus. In other mammals, some insects and gastropods, uric acid is enzymatically degraded to the more soluble allantoin through the sequential action of three enzymes: urate oxidase, 5-hydroxyisourate (HIU) hydrolase and 2-oxo-4-hydroxy-4-carboxy-5-ureidoimidazoline (OHCU) decarboxylase. Therefore, an elective treatment for acute hyperuricemia is the administration of urate oxidase. Many organisms, including plants, some fungi and several bacteria, are able to catabolize allantoin to release nitrogen, carbon, and energy. In Arabidopsis thaliana and Eschrichia coli, S-allantoin has recently been shown to be degraded to glycolate and urea by four enzymes: allantoinase, allantoate amidohydrolase, ureidoglycine aminohydrolase, and ureidoglycolate amidohydrolase.

A modified gelatin zymography technique incorporating total protein normalization.

Science.gov (United States)

Raykin, Julia; Snider, Eric; Bheri, Sruti; Mulvihill, John; Ethier, C Ross

2017-03-15

Gelatinase zymography is a commonly used laboratory procedure; however, variability in sample loading and concentration reduce the accuracy of quantitative results obtained from this technique. To facilitate normalization of gelatinase activity by loaded protein amount, we developed a protocol using the trihalocompound 2,2,2-trichloroethanol to allow for gelatin zymography and total protein labeling within the same gel. We showed that detected protein levels increased linearly with loading, and describe a loading concentration range over which normalized gelatinase activity was constant. We conclude that in-gel total protein detection is feasible in gelatin zymography and greatly improves comparison of gelatinase activity between samples. Published by Elsevier Inc.

Biochemistry of Catabolic Reductive Dehalogenation.

Science.gov (United States)

Fincker, Maeva; Spormann, Alfred M

2017-06-20

A wide range of phylogenetically diverse microorganisms couple the reductive dehalogenation of organohalides to energy conservation. Key enzymes of such anaerobic catabolic pathways are corrinoid and Fe-S cluster-containing, membrane-associated reductive dehalogenases. These enzymes catalyze the reductive elimination of a halide and constitute the terminal reductases of a short electron transfer chain. Enzymatic and physiological studies revealed the existence of quinone-dependent and quinone-independent reductive dehalogenases that are distinguishable at the amino acid sequence level, implying different modes of energy conservation in the respective microorganisms. In this review, we summarize current knowledge about catabolic reductive dehalogenases and the electron transfer chain they are part of. We review reaction mechanisms and the role of the corrinoid and Fe-S cluster cofactors and discuss physiological implications.

Endurance performance and energy metabolism during exercise in mice with a muscle-specific defect in the control of branched-chain amino acid catabolism.

Science.gov (United States)

Xu, Minjun; Kitaura, Yasuyuki; Ishikawa, Takuya; Kadota, Yoshihiro; Terai, Chihaya; Shindo, Daichi; Morioka, Takashi; Ota, Miki; Morishita, Yukako; Ishihara, Kengo; Shimomura, Yoshiharu

2017-01-01

It is known that the catabolism of branched-chain amino acids (BCAAs) in skeletal muscle is suppressed under normal and sedentary conditions but is promoted by exercise. BCAA catabolism in muscle tissues is regulated by the branched-chain α-keto acid (BCKA) dehydrogenase complex, which is inactivated by phosphorylation by BCKA dehydrogenase kinase (BDK). In the present study, we used muscle-specific BDK deficient mice (BDK-mKO mice) to examine the effect of uncontrolled BCAA catabolism on endurance exercise performance and skeletal muscle energy metabolism. Untrained control and BDK-mKO mice showed the same performance; however, the endurance performance enhanced by 2 weeks of running training was somewhat, but significantly less in BDK-mKO mice than in control mice. Skeletal muscle of BDK-mKO mice had low levels of glycogen. Metabolome analysis showed that BCAA catabolism was greatly enhanced in the muscle of BDK-mKO mice and produced branched-chain acyl-carnitine, which induced perturbation of energy metabolism in the muscle. These results suggest that the tight regulation of BCAA catabolism in muscles is important for homeostasis of muscle energy metabolism and, at least in part, for adaptation to exercise training.

Endurance performance and energy metabolism during exercise in mice with a muscle-specific defect in the control of branched-chain amino acid catabolism.

Directory of Open Access Journals (Sweden)

Minjun Xu

Full Text Available It is known that the catabolism of branched-chain amino acids (BCAAs in skeletal muscle is suppressed under normal and sedentary conditions but is promoted by exercise. BCAA catabolism in muscle tissues is regulated by the branched-chain α-keto acid (BCKA dehydrogenase complex, which is inactivated by phosphorylation by BCKA dehydrogenase kinase (BDK. In the present study, we used muscle-specific BDK deficient mice (BDK-mKO mice to examine the effect of uncontrolled BCAA catabolism on endurance exercise performance and skeletal muscle energy metabolism. Untrained control and BDK-mKO mice showed the same performance; however, the endurance performance enhanced by 2 weeks of running training was somewhat, but significantly less in BDK-mKO mice than in control mice. Skeletal muscle of BDK-mKO mice had low levels of glycogen. Metabolome analysis showed that BCAA catabolism was greatly enhanced in the muscle of BDK-mKO mice and produced branched-chain acyl-carnitine, which induced perturbation of energy metabolism in the muscle. These results suggest that the tight regulation of BCAA catabolism in muscles is important for homeostasis of muscle energy metabolism and, at least in part, for adaptation to exercise training.

Sterylglucoside catabolism in Cryptococcus neoformans with endoglycoceramidase-related protein 2 (EGCrP2), the first steryl-β-glucosidase identified in fungi.

Science.gov (United States)

Watanabe, Takashi; Ito, Tomoharu; Goda, Hatsumi M; Ishibashi, Yohei; Miyamoto, Tomofumi; Ikeda, Kazutaka; Taguchi, Ryo; Okino, Nozomu; Ito, Makoto

2015-01-09

Cryptococcosis is an infectious disease caused by pathogenic fungi, such as Cryptococcus neoformans and Cryptococcus gattii. The ceramide structure (methyl-d18:2/h18:0) of C. neoformans glucosylceramide (GlcCer) is characteristic and strongly related to its pathogenicity. We recently identified endoglycoceramidase-related protein 1 (EGCrP1) as a glucocerebrosidase in C. neoformans and showed that it was involved in the quality control of GlcCer by eliminating immature GlcCer during the synthesis of GlcCer (Ishibashi, Y., Ikeda, K., Sakaguchi, K., Okino, N., Taguchi, R., and Ito, M. (2012) Quality control of fungus-specific glucosylceramide in Cryptococcus neoformans by endoglycoceramidase-related protein 1 (EGCrP1). J. Biol. Chem. 287, 368-381). We herein identified and characterized EGCrP2, a homologue of EGCrP1, as the enzyme responsible for sterylglucoside catabolism in C. neoformans. In contrast to EGCrP1, which is specific to GlcCer, EGCrP2 hydrolyzed various β-glucosides, including GlcCer, cholesteryl-β-glucoside, ergosteryl-β-glucoside, sitosteryl-β-glucoside, and para-nitrophenyl-β-glucoside, but not α-glucosides or β-galactosides, under acidic conditions. Disruption of the EGCrP2 gene (egcrp2) resulted in the accumulation of a glycolipid, the structure of which was determined following purification to ergosteryl-3β-glucoside, a major sterylglucoside in fungi, by mass spectrometric and two-dimensional nuclear magnetic resonance analyses. This glycolipid accumulated in vacuoles and EGCrP2 was detected in vacuole-enriched fraction. These results indicated that EGCrP2 was involved in the catabolism of ergosteryl-β-glucoside in the vacuoles of C. neoformans. Distinct growth arrest, a dysfunction in cell budding, and an abnormal vacuole morphology were detected in the egcrp2-disrupted mutants, suggesting that EGCrP2 may be a promising target for anti-cryptococcal drugs. EGCrP2, classified into glycohydrolase family 5, is the first steryl

RPE cell surface proteins in normal and dystrophic rats

International Nuclear Information System (INIS)

Clark, V.M.; Hall, M.O.

1986-01-01

Membrane-bound proteins in plasma membrane enriched fractions from cultured rat RPE were analyzed by two-dimensional gel electrophoresis. Membrane proteins were characterized on three increasingly specific levels. Total protein was visualized by silver staining. A maximum of 102 separate proteins were counted in silver-stained gels. Glycoproteins were labeled with 3H-glucosamine or 3H-fucose and detected by autoradiography. Thirty-eight fucose-labeled and 61-71 glucosamine-labeled proteins were identified. All of the fucose-labeled proteins were labeled with glucosamine-derived radioactivity. Proteins exposed at the cell surface were labeled by lactoperoxidase-catalyzed radioiodination prior to preparation of membranes for two-dimensional analysis. Forty separate 125I-labeled surface proteins were resolved by two-dimensional electrophoresis/autoradiography. Comparison with the glycoprotein map showed that a number of these surface labeled proteins were glycoproteins. Two-dimensional maps of total protein, fucose-labeled, and glucosamine-labeled glycoproteins, and 125I-labeled surface proteins of membranes from dystrophic (RCS rdy-p+) and normal (Long Evans or RCS rdy+p+) RPE were compared. No differences in the total protein or surface-labeled proteins were observed. However, the results suggest that a 183K glycoprotein is more heavily glycosylated with glucosamine and fucose in normal RPE membranes as compared to membranes from dystrophic RPE

Intracellular Growth Is Dependent on Tyrosine Catabolism in the Dimorphic Fungal Pathogen Penicillium marneffei

Science.gov (United States)

Boyce, Kylie J.; McLauchlan, Alisha; Schreider, Lena; Andrianopoulos, Alex

2015-01-01

During infection, pathogens must utilise the available nutrient sources in order to grow while simultaneously evading or tolerating the host’s defence systems. Amino acids are an important nutritional source for pathogenic fungi and can be assimilated from host proteins to provide both carbon and nitrogen. The hpdA gene of the dimorphic fungus Penicillium marneffei, which encodes an enzyme which catalyses the second step of tyrosine catabolism, was identified as up-regulated in pathogenic yeast cells. As well as enabling the fungus to acquire carbon and nitrogen, tyrosine is also a precursor in the formation of two types of protective melanin; DOPA melanin and pyomelanin. Chemical inhibition of HpdA in P. marneffei inhibits ex vivo yeast cell production suggesting that tyrosine is a key nutrient source during infectious growth. The genes required for tyrosine catabolism, including hpdA, are located in a gene cluster and the expression of these genes is induced in the presence of tyrosine. A gene (hmgR) encoding a Zn(II)2-Cys6 binuclear cluster transcription factor is present within the cluster and is required for tyrosine induced expression and repression in the presence of a preferred nitrogen source. AreA, the GATA-type transcription factor which regulates the global response to limiting nitrogen conditions negatively regulates expression of cluster genes in the absence of tyrosine and is required for nitrogen metabolite repression. Deletion of the tyrosine catabolic genes in the cluster affects growth on tyrosine as either a nitrogen or carbon source and affects pyomelanin, but not DOPA melanin, production. In contrast to other genes of the tyrosine catabolic cluster, deletion of hpdA results in no growth within macrophages. This suggests that the ability to catabolise tyrosine is not required for macrophage infection and that HpdA has an additional novel role to that of tyrosine catabolism and pyomelanin production during growth in host cells. PMID:25812137

The homogentisate pathway: a central catabolic pathway involved in the degradation of L-phenylalanine, L-tyrosine, and 3-hydroxyphenylacetate in Pseudomonas putida.

Science.gov (United States)

Arias-Barrau, Elsa; Olivera, Elías R; Luengo, José M; Fernández, Cristina; Galán, Beatriz; García, José L; Díaz, Eduardo; Miñambres, Baltasar

2004-08-01

Pseudomonas putida metabolizes Phe and Tyr through a peripheral pathway involving hydroxylation of Phe to Tyr (PhhAB), conversion of Tyr into 4-hydroxyphenylpyruvate (TyrB), and formation of homogentisate (Hpd) as the central intermediate. Homogentisate is then catabolized by a central catabolic pathway that involves three enzymes, homogentisate dioxygenase (HmgA), fumarylacetoacetate hydrolase (HmgB), and maleylacetoacetate isomerase (HmgC), finally yielding fumarate and acetoacetate. Whereas the phh, tyr, and hpd genes are not linked in the P. putida genome, the hmgABC genes appear to form a single transcriptional unit. Gel retardation assays and lacZ translational fusion experiments have shown that hmgR encodes a specific repressor that controls the inducible expression of the divergently transcribed hmgABC catabolic genes, and homogentisate is the inducer molecule. Footprinting analysis revealed that HmgR protects a region in the Phmg promoter that spans a 17-bp palindromic motif and an external direct repetition from position -16 to position 29 with respect to the transcription start site. The HmgR protein is thus the first IclR-type regulator that acts as a repressor of an aromatic catabolic pathway. We engineered a broad-host-range mobilizable catabolic cassette harboring the hmgABC, hpd, and tyrB genes that allows heterologous bacteria to use Tyr as a unique carbon and energy source. Remarkably, we show here that the catabolism of 3-hydroxyphenylacetate in P. putida U funnels also into the homogentisate central pathway, revealing that the hmg cluster is a key catabolic trait for biodegradation of a small number of aromatic compounds.

Acetaldehyde binding increases the catabolism of rat serum low-density lipoproteins

International Nuclear Information System (INIS)

Savolainen, M.J.; Baraona, E.; Lieber, C.S.

1987-01-01

Acetaldehyde was found to form adducts with rat serum lipoproteins. The binding of [ 14 C]acetaldehyde to lipoproteins was studied at low concentrations which are known to exist during ethanol oxidation. The amount of lipoprotein adducts was a linear function of acetaldehyde concentration up to 250 μM. Incubation of rat plasma low-density lipoproteins (LDL) with 200 μM acetaldehyde increased the disappearance rate of the 3 H-label from the cholesterol ester moiety of LDL injected into normal rats. The data show that even low concentrations of acetaldehyde are capable of affecting LDL metabolism. These findings may provide an explanation for the low concentrations of serum LDL in alcoholics. The alcohol-induced hyperlipidemia includes either a lack of increase or a decrease in the low-density lipoprotein (LDL) concentration, but the underlying mechanism is not known. It has been shown previously, that the acetylation of lysine residues of LDL apoprotein (apoB) by acetanhydride leads to rapid uptake of LDL particles by macrophages through a non-LDL receptor pathway. Since acetaldehyde, the first toxic metabolite of ethanol, is a chemically reactive compound capable of binding to proteins, they tested whether acetaldehyde forms adducts with serum lipoproteins and subsequently alters the catabolism of LDL. 19 references, 2 figures, 1 table

In Vivo Determination of Site and Rate of Insulin Catabolism Using the Double Tracer Technique with {sup 51}Cr And {sup 131}I

Energy Technology Data Exchange (ETDEWEB)

Ritzl, F.; Feinendegen, L. E. [Institute of Medicine, Kernforschungsanlage Juelich Gmbh, Juelich, Federal Republic of Germany (Germany)

1971-02-15

Double labelling of a peptide with {sup 51}Cr and {sup 125}({sup 131})I results in an isotopic ratio that changes when and where the molecule in vivo is catabolized. Intracellular hydrolysis of the peptide liberates the iodine into the iodine pool, whereas the chromium by virtue of being a multivalent ion enters a new linkage at the site of breakdown. The isotopic ratio at the site of breakdown alters concomitantly with the hydrolysis rate. Experiments with {sup 51}Cr- and {sup 125}I-labelled insulin in mice in vivo and in vitro showed the liver (not muscle), bone (including marrow) and thyroid gland to be the major site of insulin catabolism with a half-life of approximately 10 min. In eight normal persons and diabetic patients insulin catabolism was analysed by the whole body counter following an iv injection of 0.77-0.95 {mu}g insulin labelled with {sup 51}Cr and {sup 131}I. Counts were taken simultaneously from the area of the liver, thyroid, thigh and posterior pelvis. Again, the.data indicated the liver as the site of insulin catabolism, the normal half-life being approximately 20 min. Iodine- labelled insulin was commercially supplied. {sup 51}Cr-labelled insulin, prepared according to the methods of Kavai and Kesztyues, was analysed by immune precipitation and Sephadex G200 chromatography. In the countercurrent distribution the {sup 51}Cr insulin showed enhanced water solubility. (author)

Comparison of human myofibrillar protein catabolic rate derived from 3-methylhistidine excretion with synthetic rate from muscle biopsies during L-(. cap alpha. -/sup 15/N)lysine infusion

Energy Technology Data Exchange (ETDEWEB)

McKeran, R O; Halliday, D; Purkiss, P [Clinical Research Centre, Harrow (UK). Div. of Inherited Metabolic Diseases and Clinical Investigation

1978-05-01

Urine was collected in five healthy men over 10 to 14 days, with fasting blood samples on days 1, 5 and 10, whilst they consumed a standard creatine-free diet, which was quantitatively related to their body surface area. The urinary excretion of 3-methylhistidine fell to a plateau by day 5 in all subjects. Myofibrillar protein catabolic rate calculated from the mean value of 3-methylhistidine excretion from day 5 to day 10 averaged 1.21 g day/sup -1/ kg/sup -1/ body weight. The average turnover of muscle myofibrillar protein was calculated to be 2.16%/day. From a previous study using continuous intravenous infusion of L-(a-/sup 15/N)lysine with serial muscle biopsies on the same subjects, the mean myofibrillar protein synthetic rate was calculated to be 0.82 g day/sup -1/ kg/sup -1/ body weight, and the mean turnover rate was 1.47%/day of total muscle myofibrillar protein. The estimations of myofibrillar protein turnover rate derived from the two methods are compared and the differences discussed.

Incorporating variations in pesticide catabolic activity into a GIS-based groundwater risk assessment

Energy Technology Data Exchange (ETDEWEB)

Posen, Paulette [School of Environmental Sciences, University of East Anglia, Earlham Road, Norwich NR4 7TJ (United Kingdom)]. E-mail: p.posen@uea.ac.uk; Lovett, Andrew [School of Environmental Sciences, University of East Anglia, Earlham Road, Norwich NR4 7TJ (United Kingdom); Hiscock, Kevin [School of Environmental Sciences, University of East Anglia, Earlham Road, Norwich NR4 7TJ (United Kingdom); Evers, Sarah [Environment Agency, Olton Court, 10 Warwick Road, Olton, Solihull, B92 7HX (United Kingdom); Ward, Rob [Environment Agency, Olton Court, 10 Warwick Road, Olton, Solihull, B92 7HX (United Kingdom); Reid, Brian [School of Environmental Sciences, University of East Anglia, Earlham Road, Norwich NR4 7TJ (United Kingdom)

2006-08-31

The catabolic activity of incumbent microorganisms in soil samples of eleven dissimilar soil series was investigated, with respect to the herbicide isoproturon. Soils were collected from a 30 x 37 km area of river catchment to the north-west of London, England. Catabolic activity in each soil type during a 500 h assay was determined by {sup 14}C-radiorespirometry. Results showed four soils that exhibited high levels of catabolic activity (33-44% mineralisation) while the remaining seven soils showed lower levels of catabolic activity (12-16% mineralisation). There was evidence to suggest that soils exhibiting high catabolic activity had low (< 22%) clay content and tended towards lower organic carbon content (< 2.7%), but that these higher levels of catabolic activity were also related to pre-exposure to isoproturon. The {sup 14}C-radiorespirometric results were used to produce a GIS layer representing levels of catabolic activity for the dissimilar soils across the study area. This layer was combined with other GIS layers relating to pesticide attenuation, including soil organic carbon content, depth to groundwater and hydrogeology, to produce a map showing risk of groundwater contamination by isoproturon. The output from this approach was compared with output from an attenuation-only approach and differences appraised. Inclusion of the catabolism layer resulted in a lowering of risk in the model in 15% of the study area. Although there appears to be limited benefit in including pesticide catabolic activity in this regional-scale groundwater risk model, this type of addition could be useful in a site-specific risk assessment.

Overexpression, purification, crystallization and preliminary structural studies of catabolic ornithine transcarbamylase from Lactobacillus hilgardii

Energy Technology Data Exchange (ETDEWEB)

Rivas, Blanca de las; Rodríguez, Héctor [Instituto de Fermentaciones Industriales, CSIC, Juan de la Cierva 3, 28006 Madrid (Spain); Angulo, Iván [Grupo de Cristalografía Macromolecular y Biología Estructural, Instituto Rocasolano, CSIC, Serrano 119, 28006 Madrid (Spain); 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)

2007-07-01

The catabolic ornithine transcarbamylase (cOTC) from L. hilgardii has been overexpressed in E. coli, purified and crystallized under two different experimental conditions. The structure has been solved by the molecular-replacement method using the atomic coordinates of catabolic ornithine transcarbamylase from P. aeruginosa as the search model. The catabolic ornithine transcarbamylase (cOTC; EC 2.1.3.3) from the lactic acid bacteria Lactobacillus hilgardii is a key protein involved in the degradation of arginine during malolactic fermentation. cOTC containing an N-terminal His{sub 6} tag has been overexpressed in Escherichia coli, purified and crystallized under two different experimental conditions using the hanging-drop vapour-diffusion method. Crystals obtained from a solution containing 8%(w/v) PEG 4000, 75 mM sodium acetate pH 4.6 belong to the trigonal space group P321 and have unit-cell parameters a = b = 157.04, c = 79.28 Å. Conversely, crystals grown in 20%(v/v) 2-methyl-2,4-pentanediol, 7.5%(w/v) PEG 4000, 100 mM HEPES pH 7.8 belong to the monoclinic space group C2 and have unit-cell parameters a = 80.06, b = 148.90, c = 91.67 Å, β = 100.25°. Diffraction data were collected in-house to 3.00 and 2.91 Å resolution for trigonal and monoclinic crystals, respectively. The estimated Matthews coefficient for the crystal forms were 2.36 and 2.24 Å{sup 3} Da{sup −1}, respectively, corresponding to 48% and 45% solvent content. In both cases, the results are consistent with the presence of three protein subunits in the asymmetric unit. The structure of cOTC has been determined by the molecular-replacement method using the atomic coordinates of cOTC from Pseudomonas aeruginosa (PDB code) as the search model.

Overexpression, purification, crystallization and preliminary structural studies of catabolic ornithine transcarbamylase from Lactobacillus hilgardii

International Nuclear Information System (INIS)

Rivas, Blanca de las; Rodríguez, Héctor; Angulo, Iván; Muñoz, Rosario; Mancheño, José M.

2007-01-01

The catabolic ornithine transcarbamylase (cOTC) from L. hilgardii has been overexpressed in E. coli, purified and crystallized under two different experimental conditions. The structure has been solved by the molecular-replacement method using the atomic coordinates of catabolic ornithine transcarbamylase from P. aeruginosa as the search model. The catabolic ornithine transcarbamylase (cOTC; EC 2.1.3.3) from the lactic acid bacteria Lactobacillus hilgardii is a key protein involved in the degradation of arginine during malolactic fermentation. cOTC containing an N-terminal His 6 tag has been overexpressed in Escherichia coli, purified and crystallized under two different experimental conditions using the hanging-drop vapour-diffusion method. Crystals obtained from a solution containing 8%(w/v) PEG 4000, 75 mM sodium acetate pH 4.6 belong to the trigonal space group P321 and have unit-cell parameters a = b = 157.04, c = 79.28 Å. Conversely, crystals grown in 20%(v/v) 2-methyl-2,4-pentanediol, 7.5%(w/v) PEG 4000, 100 mM HEPES pH 7.8 belong to the monoclinic space group C2 and have unit-cell parameters a = 80.06, b = 148.90, c = 91.67 Å, β = 100.25°. Diffraction data were collected in-house to 3.00 and 2.91 Å resolution for trigonal and monoclinic crystals, respectively. The estimated Matthews coefficient for the crystal forms were 2.36 and 2.24 Å 3 Da −1 , respectively, corresponding to 48% and 45% solvent content. In both cases, the results are consistent with the presence of three protein subunits in the asymmetric unit. The structure of cOTC has been determined by the molecular-replacement method using the atomic coordinates of cOTC from Pseudomonas aeruginosa (PDB code) as the search model

Incorporating variations in pesticide catabolic activity into a GIS-based groundwater risk assessment

International Nuclear Information System (INIS)

Posen, Paulette; Lovett, Andrew; Hiscock, Kevin; Evers, Sarah; Ward, Rob; Reid, Brian

2006-01-01

The catabolic activity of incumbent microorganisms in soil samples of eleven dissimilar soil series was investigated, with respect to the herbicide isoproturon. Soils were collected from a 30 x 37 km area of river catchment to the north-west of London, England. Catabolic activity in each soil type during a 500 h assay was determined by 14 C-radiorespirometry. Results showed four soils that exhibited high levels of catabolic activity (33-44% mineralisation) while the remaining seven soils showed lower levels of catabolic activity (12-16% mineralisation). There was evidence to suggest that soils exhibiting high catabolic activity had low ( 14 C-radiorespirometric results were used to produce a GIS layer representing levels of catabolic activity for the dissimilar soils across the study area. This layer was combined with other GIS layers relating to pesticide attenuation, including soil organic carbon content, depth to groundwater and hydrogeology, to produce a map showing risk of groundwater contamination by isoproturon. The output from this approach was compared with output from an attenuation-only approach and differences appraised. Inclusion of the catabolism layer resulted in a lowering of risk in the model in 15% of the study area. Although there appears to be limited benefit in including pesticide catabolic activity in this regional-scale groundwater risk model, this type of addition could be useful in a site-specific risk assessment

Catabolism of biomass-derived sugars in fungi and metabolic engineering as a tool for organic acid production

Energy Technology Data Exchange (ETDEWEB)

Koivistoinen, O.

2013-11-01

The use of metabolic engineering as a tool for production of biochemicals and biofuels requires profound understanding of cell metabolism. The pathways for the most abundant and most important hexoses have already been studied quite extensively but it is also important to get a more complete picture of sugar catabolism. In this thesis, catabolic pathways of L-rhamnose and D-galactose were studied in fungi. Both of these hexoses are present in plant biomass, such as in hemicellulose and pectin. Galactoglucomannan, a type of hemicellulose that is especially rich in softwood, is an abundant source of D-galactose. As biotechnology is moving from the usage of edible and easily metabolisable carbon sources towards the increased use of lignocellulosic biomass, it is important to understand how the different sugars can be efficiently turned into valuable biobased products. Identification of the first fungal L-rhamnose 1-dehydrogenase gene, which codes for the first enzyme of the fungal catabolic L-rhamnose pathway, showed that the protein belongs to a protein family of short-chain alcohol dehydrogenases. Sugar dehydrogenases oxidising a sugar to a sugar acid are not very common in fungi and thus the identification of the L-rhamnose dehydrogenase gene provides more understanding of oxidative sugar catabolism in eukaryotic microbes. Further studies characterising the L-rhamnose cluster in the yeast Scheffersomyces stipitis including the expression of the L-rhamnonate dehydratase in Saccharomyces cerevisiae finalised the biochemical characterisation of the enzymes acting on the pathway. In addition, more understanding of the regulation and evolution of the pathway was gained. D-Galactose catabolism was studied in the filamentous fungus Aspergillus niger. Two genes coding for the enzymes of the oxido-reductive pathway were identified. Galactitol dehydrogenase is the second enzyme of the pathway converting galactitol to L-xylo-3-hexulose. The galactitol dehydrogenase encoding

WEBnm@: a web application for normal mode analyses of proteins

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Reuter Nathalie

2005-03-01

Full Text Available Abstract Background Normal mode analysis (NMA has become the method of choice to investigate the slowest motions in macromolecular systems. NMA is especially useful for large biomolecular assemblies, such as transmembrane channels or virus capsids. NMA relies on the hypothesis that the vibrational normal modes having the lowest frequencies (also named soft modes describe the largest movements in a protein and are the ones that are functionally relevant. Results We developed a web-based server to perform normal modes calculations and different types of analyses. Starting from a structure file provided by the user in the PDB format, the server calculates the normal modes and subsequently offers the user a series of automated calculations; normalized squared atomic displacements, vector field representation and animation of the first six vibrational modes. Each analysis is performed independently from the others and results can be visualized using only a web browser. No additional plug-in or software is required. For users who would like to analyze the results with their favorite software, raw results can also be downloaded. The application is available on http://www.bioinfo.no/tools/normalmodes. We present here the underlying theory, the application architecture and an illustration of its features using a large transmembrane protein as an example. Conclusion We built an efficient and modular web application for normal mode analysis of proteins. Non specialists can easily and rapidly evaluate the degree of flexibility of multi-domain protein assemblies and characterize the large amplitude movements of their domains.

Exercise promotes BCAA catabolism: effects of BCAA supplementation on skeletal muscle during exercise.

Science.gov (United States)

Shimomura, Yoshiharu; Murakami, Taro; Nakai, Naoya; Nagasaki, Masaru; Harris, Robert A

2004-06-01

Branched-chain amino acids (BCAAs) are essential amino acids that can be oxidized in skeletal muscle. It is known that BCAA oxidation is promoted by exercise. The mechanism responsible for this phenomenon is attributed to activation of the branched-chain alpha-keto acid dehydrogenase (BCKDH) complex, which catalyzes the second-step reaction of the BCAA catabolic pathway and is the rate-limiting enzyme in the pathway. This enzyme complex is regulated by a phosphorylation-dephosphorylation cycle. The BCKDH kinase is responsible for inactivation of the complex by phosphorylation, and the activity of the kinase is inversely correlated with the activity state of the BCKDH complex, which suggests that the kinase is the primary regulator of the complex. We found recently that administration of ligands for peroxisome proliferator-activated receptor-alpha (PPARalpha) in rats caused activation of the hepatic BCKDH complex in association with a decrease in the kinase activity, which suggests that promotion of fatty acid oxidation upregulates the BCAA catabolism. Long-chain fatty acids are ligands for PPARalpha, and the fatty acid oxidation is promoted by several physiological conditions including exercise. These findings suggest that fatty acids may be one of the regulators of BCAA catabolism and that the BCAA requirement is increased by exercise. Furthermore, BCAA supplementation before and after exercise has beneficial effects for decreasing exercise-induced muscle damage and promoting muscle-protein synthesis; this suggests the possibility that BCAAs are a useful supplement in relation to exercise and sports.

Shifting patterns of nitrogen excretion and amino acid catabolism capacity during the life cycle of the sea lamprey (Petromyzon marinus).

Science.gov (United States)

Wilkie, Michael P; Claude, Jaime F; Cockshutt, Amanda; Holmes, John A; Wang, Yuxiang S; Youson, John H; Walsh, Patrick J

2006-01-01

The jawless fish, the sea lamprey (Petromyzon marinus), spends part of its life as a burrow-dwelling, suspension-feeding larva (ammocoete) before undergoing a metamorphosis into a free swimming, parasitic juvenile that feeds on the blood of fishes. We predicted that animals in this juvenile, parasitic stage have a great capacity for catabolizing amino acids when large quantities of protein-rich blood are ingested. The sixfold to 20-fold greater ammonia excretion rates (J(Amm)) in postmetamorphic (nonfeeding) and parasitic lampreys compared with ammocoetes suggested that basal rates of amino acid catabolism increased following metamorphosis. This was likely due to a greater basal amino acid catabolizing capacity in which there was a sixfold higher hepatic glutamate dehydrogenase (GDH) activity in parasitic lampreys compared with ammocoetes. Immunoblotting also revealed that GDH quantity was 10-fold and threefold greater in parasitic lampreys than in ammocoetes and upstream migrant lampreys, respectively. Higher hepatic alanine and aspartate aminotransferase activities in the parasitic lampreys also suggested an enhanced amino acid catabolizing capacity in this life stage. In contrast to parasitic lampreys, the twofold larger free amino acid pool in the muscle of upstream migrant lampreys confirmed that this period of natural starvation is accompanied by a prominent proteolysis. Carbamoyl phosphate synthetase III was detected at low levels in the liver of parasitic and upstream migrant lampreys, but there was no evidence of extrahepatic (muscle, intestine) urea production via the ornithine urea cycle. However, detection of arginase activity and high concentrations of arginine in the liver at all life stages examined infers that arginine hydrolysis is an important source of urea. We conclude that metamorphosis is accompanied by a metabolic reorganization that increases the capacity of parasitic sea lampreys to catabolize intermittently large amino acid loads arising

Immunosuppressive Tryptophan Catabolism and Gut Mucosal Dysfunction Following Early HIV Infection

NARCIS (Netherlands)

Jenabian, Mohammad-Ali; El-Far, Mohamed; Vyboh, Kishanda; Kema, Ido; Costiniuk, Cecilia T.; Thomas, Rejean; Baril, Jean-Guy; LeBlanc, Roger; Kanagaratham, Cynthia; Radzioch, Danuta; Allam, Ossama; Ahmad, Ali; Lebouche, Bertrand; Tremblay, Cecile; Ancuta, Petronela; Routy, Jean-Pierre

2015-01-01

Background. Tryptophan (Trp) catabolism into kynurenine (Kyn) contributes to immune dysfunction in chronic human immunodeficiency virus (HIV) infection. To better define the relationship between Trp catabolism, inflammation, gut mucosal dysfunction, and the role of early antiretroviral therapy

Variable carbon catabolism among Salmonella enterica serovar Typhi isolates.

Directory of Open Access Journals (Sweden)

Lay Ching Chai

Full Text Available BACKGROUND: Salmonella enterica serovar Typhi (S. Typhi is strictly a human intracellular pathogen. It causes acute systemic (typhoid fever and chronic infections that result in long-term asymptomatic human carriage. S. Typhi displays diverse disease manifestations in human infection and exhibits high clonality. The principal factors underlying the unique lifestyle of S. Typhi in its human host during acute and chronic infections remain largely unknown and are therefore the main objective of this study. METHODOLOGY/PRINCIPAL FINDINGS: To obtain insight into the intracellular lifestyle of S. Typhi, a high-throughput phenotypic microarray was employed to characterise the catabolic capacity of 190 carbon sources in S. Typhi strains. The success of this study lies in the carefully selected library of S. Typhi strains, including strains from two geographically distinct areas of typhoid endemicity, an asymptomatic human carrier, clinical stools and blood samples and sewage-contaminated rivers. An extremely low carbon catabolic capacity (27% of 190 carbon substrates was observed among the strains. The carbon catabolic profiles appeared to suggest that S. Typhi strains survived well on carbon subtrates that are found abundantly in the human body but not in others. The strains could not utilise plant-associated carbon substrates. In addition, α-glycerolphosphate, glycerol, L-serine, pyruvate and lactate served as better carbon sources to monosaccharides in the S. Typhi strains tested. CONCLUSION: The carbon catabolic profiles suggest that S. Typhi could survive and persist well in the nutrient depleted metabolic niches in the human host but not in the environment outside of the host. These findings serve as caveats for future studies to understand how carbon catabolism relates to the pathogenesis and transmission of this pathogen.

Magnolol Affects Cellular Proliferation, Polyamine Biosynthesis and Catabolism-Linked Protein Expression and Associated Cellular Signaling Pathways in Human Prostate Cancer Cells in vitro

Directory of Open Access Journals (Sweden)

Brendan T. McKeown

2015-01-01

Full Text Available Background: Prostate cancer is the most commonly diagnosed form of cancer in men in Canada and the United States. Both genetic and environmental factors contribute to the development and progression of many cancers, including prostate cancer. Context and purpose of this study: This study investigated the effects of magnolol, a compound found in the roots and bark of the magnolia tree Magnolia officinalis, on cellular proliferation and proliferation-linked activities of PC3 human prostate cancer cells in vitro. Results: PC3 cells exposed to magnolol at a concentration of 80 μM for 6 hours exhibited decreased protein expression of ornithine decarboxylase, a key regulator in polyamine biosynthesis, as well as affecting the expression of other proteins involved in polyamine biosynthesis and catabolism. Furthermore, protein expression of the R2 subunit of ribonucleotide reductase, a key regulatory protein associated with DNA synthesis, was significantly decreased. Finally, the MAPK (mitogen-activated protein kinase, PI3K (phosphatidylinositol 3-kinase, NFκB (nuclear factor of kappa-light-chain-enhancer of activated B cells and AP-1 (activator protein 1 cellular signaling pathways were assayed to determine which, if any, of these pathways magnolol exposure would alter. Protein expressions of p-JNK-1 and c-jun were significantly increased while p-p38, JNK-1/2, PI3Kp85, p-PI3Kp85, p-Akt, NFκBp65, p-IκBα and IκBα protein expressions were significantly decreased. Conclusions: These alterations further support the anti-proliferative effects of magnolol on PC3 human prostate cancer cells in vitro and suggest that magnolol may have potential as a novel anti-prostate cancer agent.

Relation between Protein Intrinsic Normal Mode Weights and Pre-Existing Conformer Populations.

Science.gov (United States)

Ozgur, Beytullah; Ozdemir, E Sila; Gursoy, Attila; Keskin, Ozlem

2017-04-20

Intrinsic fluctuations of a protein enable it to sample a large repertoire of conformers including the open and closed forms. These distinct forms of the protein called conformational substates pre-exist together in equilibrium as an ensemble independent from its ligands. The role of ligand might be simply to alter the equilibrium toward the most appropriate form for binding. Normal mode analysis is proved to be useful in identifying the directions of conformational changes between substates. In this study, we demonstrate that the ratios of normalized weights of a few normal modes driving the protein between its substates can give insights about the ratios of kinetic conversion rates of the substates, although a direct relation between the eigenvalues and kinetic conversion rates or populations of each substate could not be observed. The correlation between the normalized mode weight ratios and the kinetic rate ratios is around 83% on a set of 11 non-enzyme proteins and around 59% on a set of 17 enzymes. The results are suggestive that mode motions carry intrinsic relations with thermodynamics and kinetics of the proteins.

Identification of the First Riboflavin Catabolic Gene Cluster Isolated from Microbacterium maritypicum G10*

Science.gov (United States)

Xu, Hui; Chakrabarty, Yindrila; Philmus, Benjamin; Mehta, Angad P.; Bhandari, Dhananjay; Hohmann, Hans-Peter; Begley, Tadhg P.

2016-01-01

Riboflavin is a common cofactor, and its biosynthetic pathway is well characterized. However, its catabolic pathway, despite intriguing hints in a few distinct organisms, has never been established. This article describes the isolation of a Microbacterium maritypicum riboflavin catabolic strain, and the cloning of the riboflavin catabolic genes. RcaA, RcaB, RcaD, and RcaE were overexpressed and biochemically characterized as riboflavin kinase, riboflavin reductase, ribokinase, and riboflavin hydrolase, respectively. Based on these activities, a pathway for riboflavin catabolism is proposed. PMID:27590337

Catabolic factors and osteoarthritis-conditioned medium inhibit chondrogenesis of human mesenchymal stem cells.

Science.gov (United States)

Heldens, Genoveva T H; Blaney Davidson, Esmeralda N; Vitters, Elly L; Schreurs, B Willem; Piek, Ester; van den Berg, Wim B; van der Kraan, Peter M

2012-01-01

Articular cartilage has a very limited intrinsic repair capacity leading to progressive joint damage. Therapies involving tissue engineering depend on chondrogenic differentiation of progenitor cells. This chondrogenic differentiation will have to survive in a diseased joint. We postulate that catabolic factors in this environment inhibit chondrogenesis of progenitor cells. We investigated the effect of a catabolic environment on chondrogenesis in pellet cultures of human mesenchymal stem cells (hMSCs). We exposed chondrogenically differentiated hMSC pellets, to interleukin (IL)-1α, tumor necrosis factor (TNF)-α or conditioned medium derived from osteoarthritic synovium (CM-OAS). IL-1α and TNF-α in CM-OAS were blocked with IL-1Ra or Enbrel, respectively. Chondrogenesis was determined by chondrogenic markers collagen type II, aggrecan, and the hypertrophy marker collagen type X on mRNA. Proteoglycan deposition was analyzed by safranin o staining on histology. IL-1α and TNF-α dose-dependently inhibited chondrogenesis when added at onset or during progression of differentiation, IL-1α being more potent than TNF-α. CM-OAS inhibited chondrogenesis on mRNA and protein level but varied in extent between patients. Inhibition of IL-1α partially overcame the inhibitory effect of the CM-OAS on chondrogenesis whereas the TNF-α contribution was negligible. We show that hMSC chondrogenesis is blocked by either IL-1α or TNF-α alone, but that there are additional factors present in CM-OAS that contribute to inhibition of chondrogenesis, demonstrating that catabolic factors present in OA joints inhibit chondrogenesis, thereby impairing successful tissue engineering.

Identification of the First Riboflavin Catabolic Gene Cluster Isolated from Microbacterium maritypicum G10.

Science.gov (United States)

Xu, Hui; Chakrabarty, Yindrila; Philmus, Benjamin; Mehta, Angad P; Bhandari, Dhananjay; Hohmann, Hans-Peter; Begley, Tadhg P

2016-11-04

Riboflavin is a common cofactor, and its biosynthetic pathway is well characterized. However, its catabolic pathway, despite intriguing hints in a few distinct organisms, has never been established. This article describes the isolation of a Microbacterium maritypicum riboflavin catabolic strain, and the cloning of the riboflavin catabolic genes. RcaA, RcaB, RcaD, and RcaE were overexpressed and biochemically characterized as riboflavin kinase, riboflavin reductase, ribokinase, and riboflavin hydrolase, respectively. Based on these activities, a pathway for riboflavin catabolism is proposed. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Kinome signaling through regulated protein-protein interactions in normal and cancer cells.

Science.gov (United States)

Pawson, Tony; Kofler, Michael

2009-04-01

The flow of molecular information through normal and oncogenic signaling pathways frequently depends on protein phosphorylation, mediated by specific kinases, and the selective binding of the resulting phosphorylation sites to interaction domains present on downstream targets. This physical and functional interplay of catalytic and interaction domains can be clearly seen in cytoplasmic tyrosine kinases such as Src, Abl, Fes, and ZAP-70. Although the kinase and SH2 domains of these proteins possess similar intrinsic properties of phosphorylating tyrosine residues or binding phosphotyrosine sites, they also undergo intramolecular interactions when linked together, in a fashion that varies from protein to protein. These cooperative interactions can have diverse effects on substrate recognition and kinase activity, and provide a variety of mechanisms to link the stimulation of catalytic activity to substrate recognition. Taken together, these data have suggested how protein kinases, and the signaling pathways in which they are embedded, can evolve complex properties through the stepwise linkage of domains within single polypeptides or multi-protein assemblies.

The effects of acetaldehyde and acrolein on muscle catabolism in C2 myotubes.

Science.gov (United States)

Rom, Oren; Kaisari, Sharon; Aizenbud, Dror; Reznick, Abraham Z

2013-12-01

The toxic aldehydes acetaldehyde and acrolein were previously suggested to damage skeletal muscle. Several conditions in which exposure to acetaldehyde and acrolein is increased were associated with muscle wasting and dysfunction. These include alcoholic myopathy, renal failure, oxidative stress, and inflammation. A main exogenous source of both acetaldehyde and acrolein is cigarette smoking, which was previously associated with increased muscle catabolism. Recently, we have shown that exposure of skeletal myotubes to cigarette smoke stimulated muscle catabolism via increased oxidative stress, activation of p38 MAPK, and upregulation of muscle-specific E3 ubiquitin ligases. In this study, we aimed to investigate the effects of acetaldehyde and acrolein on catabolism of skeletal muscle. Skeletal myotubes differentiated from the C2 myoblast cell line were exposed to acetaldehyde or acrolein and their effects on signaling pathways related to muscle catabolism were studied. Exposure of myotubes to acetaldehyde did not promote muscle catabolism. However, exposure to acrolein caused increased generation of free radicals, activation of p38 MAPK, upregulation of the muscle-specific E3 ligases atrogin-1 and MuRF1, degradation of myosin heavy chain, and atrophy of myotubes. Inhibition of p38 MAPK by SB203580 abolished acrolein-induced muscle catabolism. Our findings demonstrate that acrolein but not acetaldehyde activates a signaling cascade resulting in muscle catabolism in skeletal myotubes. Although within the limitations of an in vitro study, these findings indicate that acrolein may promote muscle wasting in conditions of increased exposure to this aldehyde. Copyright © 2013 Elsevier Inc. All rights reserved.

Intrinsic and induced isoproturon catabolic activity in dissimilar soils and soils under dissimilar land use

International Nuclear Information System (INIS)

Reid, Brian J.; Papanikolaou, Niki D.; Wilcox, Ronah K.

2005-01-01

The catabolic activity with respect to the systemic herbicide isoproturon was determined in soil samples by 14 C-radiorespirometry. The first experiment assessed levels of intrinsic catabolic activity in soil samples that represented three dissimilar soil series under arable cultivation. Results showed average extents of isoproturon mineralisation (after 240 h assay time) in the three soil series to be low. A second experiment assessed the impact of addition of isoproturon (0.05 μg kg -1 ) into these soils on the levels of catabolic activity following 28 days of incubation. Increased catabolic activity was observed in all three soils. A third experiment assessed levels of intrinsic catabolic activity in soil samples representing a single soil series managed under either conventional agricultural practice (including the use of isoproturon) or organic farming practice (with no use of isoproturon). Results showed higher (and more consistent) levels of isoproturon mineralisation in the soil samples collected from conventional land use. The final experiment assessed the impact of isoproturon addition on the levels of inducible catabolic activity in these soils. The results showed no significant difference in the case of the conventional farm soil samples while the induction of catabolic activity in the organic farm soil samples was significant. - Dissimilar levels of isoproturon catabolic activity in dissimilar soils and soils under dissimilar land use influence inferred risk

Intrinsic and induced isoproturon catabolic activity in dissimilar soils and soils under dissimilar land use

Energy Technology Data Exchange (ETDEWEB)

Reid, Brian J. [School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ (United Kingdom)]. E-mail: b.reid@uea.ac.uk; Papanikolaou, Niki D. [School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ (United Kingdom); Wilcox, Ronah K. [School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ (United Kingdom)

2005-02-01

The catabolic activity with respect to the systemic herbicide isoproturon was determined in soil samples by {sup 14}C-radiorespirometry. The first experiment assessed levels of intrinsic catabolic activity in soil samples that represented three dissimilar soil series under arable cultivation. Results showed average extents of isoproturon mineralisation (after 240 h assay time) in the three soil series to be low. A second experiment assessed the impact of addition of isoproturon (0.05 {mu}g kg{sup -1}) into these soils on the levels of catabolic activity following 28 days of incubation. Increased catabolic activity was observed in all three soils. A third experiment assessed levels of intrinsic catabolic activity in soil samples representing a single soil series managed under either conventional agricultural practice (including the use of isoproturon) or organic farming practice (with no use of isoproturon). Results showed higher (and more consistent) levels of isoproturon mineralisation in the soil samples collected from conventional land use. The final experiment assessed the impact of isoproturon addition on the levels of inducible catabolic activity in these soils. The results showed no significant difference in the case of the conventional farm soil samples while the induction of catabolic activity in the organic farm soil samples was significant. - Dissimilar levels of isoproturon catabolic activity in dissimilar soils and soils under dissimilar land use influence inferred risk.

Combination of recreational soccer and caloric restricted diet reduces markers of protein catabolism and cardiovascular risk in patients with type 2 diabetes

DEFF Research Database (Denmark)

de Sousa, M Vieira; Fukui, R; Krustrup, Peter

2017-01-01

Background: Moderate calorie-restricted diets and exercise training prevent loss of lean mass and cardiovascular risk. Because adherence to routine exercise recommendation is generally poor, we utilized recreational soccer training as a novel therapeutic exercise intervention in type 2 diabetes (T2......D) patients. Objective: We compared the effects of acute and chronic soccer training plus calorie-restricted diet on protein catabolism and cardiovascular risk markers in T2D. Design, setting and subjects: Fifty-one T2D patients (61.1±6.4 years, 29 females: 22 males) were randomly allocated...... to the soccer+diet-group (SDG) or to the dietgroup (DG). The 40-min soccer sessions were held 3 times per week for 12 weeks. Results: Nineteen participants attended 100% of scheduled soccer sessions, and none suffered any injuries. The SDG group showed higher levels of growth hormone (GH), free fatty acids...

Metabolic control analysis of Aspergillus niger L-arabinose catabolism

DEFF Research Database (Denmark)

de Groot, M.J.L.; Prathumpai, Wai; Visser, J.

2005-01-01

A mathematical model of the L-arabinose/D-xylose catabolic pathway of Aspergillus niger was constructed based on the kinetic properties of the enzymes. For this purpose L-arabinose reductase, L-arabitol dehydrogenase and D-xylose reductase were purified using dye-affinity chromatography...... aiming at either flux or metabolite level optimization of the L-arabinose catabolic pathway of A. niger. Faster L-arabinose utilization may enhance utilization of readily available organic waste containing hemicelluloses to be converted into industrially interesting metabolites or valuable enzymes...

Relationship of long-term macronutrients intake on anabolic-catabolic hormones in female elite volleyball players.

Science.gov (United States)

Mielgo Ayuso, Juan; Zourdos, Michael C; Urdampilleta, Aritz; Calleja González, Julio; Seco, Jesús; Córdova, Alfredo

2017-10-24

Specific macronutrient distribution and training can alter acute and chronic hormone behavior and, subsequently, sport performance. The main aim was to examine relationships between dietary intake and anabolic/catabolic hormone response in elite female volleyball players during a 29-week season. Twenty-two elite female volleyballers (26.4 ± 5.6 years; 178 ± 9 cm; 67.1 ± 7.5 kg) had dietary intake (seven-day dietary recall and food frequency questionnaire), blood concentration of anabolic/catabolic hormones concentration, physical performance, and body composition assessed at four time points: a) T1: baseline/pre-testing; b) T2: eleven weeks after T1; c) T3: ten weeks after T2; and d) T4: eight weeks after T3. Hormones evaluated were: total testosterone (TT), free testosterone (FT) adrenocorticotropic hormone (ACTH), and cortisol (C), along with hormone ratios. Positive correlations were observed between carbohydrate/protein ratio with ΔFT (r = 0.955; p 0.05) in body mass or body mass index at any time point, and the sum of six skinfolds improved (p < 0.05) from T1 (86.5 ± 6.9 mm) to T4 (75.2 ± 5.6 mm) as did muscle mass (T1: 28.9 ± 0.7 kg vsT4: 30.1 ± 0.8 kg). Vertical jump, spike-jump and speed improved (p < 0.05) from T1 to T4. A high carbohydrate/protein ratio was associated with positive changes in anabolism, while high protein and low carbohydrates (CHO) were associated with an attenuated anabolic response.

Trichohyalin-like 1 protein, a member of fused S100 proteins, is expressed in normal and pathologic human skin

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Yamakoshi, Takako [Department of Dermatology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani, Toyama 930-0194 (Japan); Makino, Teruhiko, E-mail: tmakino@med.u-toyama.ac.jp [Department of Dermatology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani, Toyama 930-0194 (Japan); Ur Rehman, Mati; Yoshihisa, Yoko [Department of Dermatology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani, Toyama 930-0194 (Japan); Sugimori, Michiya [Department of Integrative Neuroscience, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani, Toyama 930-0194 (Japan); Shimizu, Tadamichi, E-mail: shimizut@med.u-toyama.ac.jp [Department of Dermatology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani, Toyama 930-0194 (Japan)

2013-03-01

Highlights: ► Trichohyalin-like 1 protein is a member of the fused-type S100 protein gene family. ► Specific antibodies against the C-terminus of the TCHHL1 protein were generated. ► TCHHL1 proteins were expressed in the basal layer of the normal epidermis. ► TCHHL1 proteins were strongly expressed in tumor nests of BCC and SCC. ► The expression of TCHHL1 proteins increased in epidermis of psoriasis vulgaris. - Abstract: Trichohyalin-like 1 (TCHHL1) protein is a novel member of the fused-type S100 protein gene family. The deduced amino acid sequence of TCHHL1 contains an EF-hand domain in the N-terminus, one trans-membrane domain and a nuclear localization signal. We generated specific antibodies against the C-terminus of the TCHHL1 protein and examined the expression of TCHHL1 proteins in normal and pathological human skin. An immunohistochemical study showed that TCHHL1 proteins were expressed in the basal layer of the normal epidermis. In addition, signals of TCHHL1 proteins were observed around the nuclei of cultured growing keratinocytes. Accordingly, TCHHL1 mRNA has been detected in normal skin and cultured growing keratinocytes. Furthermore, TCHHL1 proteins were strongly expressed in the peripheral areas of tumor nests in basal cell carcinomas and squamous cell carcinomas. A dramatic increase in the number of Ki67 positive cells was observed in TCHHL1-expressing areas. The expression of TCHHL1 proteins also increased in non-cancerous hyperproliferative epidermal tissues such as those of psoriasis vulgaris and lichen planus. These findings highlight the possibility that TCHHL1 proteins are expressed in growing keratinocytes of the epidermis and might be associated with the proliferation of keratinocytes.

Trichohyalin-like 1 protein, a member of fused S100 proteins, is expressed in normal and pathologic human skin

International Nuclear Information System (INIS)

Yamakoshi, Takako; Makino, Teruhiko; Ur Rehman, Mati; Yoshihisa, Yoko; Sugimori, Michiya; Shimizu, Tadamichi

2013-01-01

Highlights: ► Trichohyalin-like 1 protein is a member of the fused-type S100 protein gene family. ► Specific antibodies against the C-terminus of the TCHHL1 protein were generated. ► TCHHL1 proteins were expressed in the basal layer of the normal epidermis. ► TCHHL1 proteins were strongly expressed in tumor nests of BCC and SCC. ► The expression of TCHHL1 proteins increased in epidermis of psoriasis vulgaris. - Abstract: Trichohyalin-like 1 (TCHHL1) protein is a novel member of the fused-type S100 protein gene family. The deduced amino acid sequence of TCHHL1 contains an EF-hand domain in the N-terminus, one trans-membrane domain and a nuclear localization signal. We generated specific antibodies against the C-terminus of the TCHHL1 protein and examined the expression of TCHHL1 proteins in normal and pathological human skin. An immunohistochemical study showed that TCHHL1 proteins were expressed in the basal layer of the normal epidermis. In addition, signals of TCHHL1 proteins were observed around the nuclei of cultured growing keratinocytes. Accordingly, TCHHL1 mRNA has been detected in normal skin and cultured growing keratinocytes. Furthermore, TCHHL1 proteins were strongly expressed in the peripheral areas of tumor nests in basal cell carcinomas and squamous cell carcinomas. A dramatic increase in the number of Ki67 positive cells was observed in TCHHL1-expressing areas. The expression of TCHHL1 proteins also increased in non-cancerous hyperproliferative epidermal tissues such as those of psoriasis vulgaris and lichen planus. These findings highlight the possibility that TCHHL1 proteins are expressed in growing keratinocytes of the epidermis and might be associated with the proliferation of keratinocytes

Lactoferricin mediates Anti-Inflammatory and Anti-Catabolic Effects via Inhibition of IL-1 and LPS Activity in the Intervertebral Disc†

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Kim, Jae-Sung; Ellman, Michael B.; Yan, Dongyao; An, Howard S.; Kc, Ranjan; Li, Xin; Chen, Di; Xiao, Guozhi; Cs-Zabo, Gabriella; Hoskin, David W.; Buechter, D.D.; Van Wijnen, Andre J.; Im, Hee-Jeong

2013-01-01

The catabolic cytokine interleukin-1 (IL-1) and endotoxin lipopolysaccharide (LPS) are well-known inflammatory mediators involved in degenerative disc disease, and inhibitors of IL-1 and LPS may potentially be used to slow or prevent disc degeneration in vivo. Here, we elucidate the striking anti-catabolic and anti-inflammatory effects of bovine lactoferricin (LfcinB) in the intervertebral disc (IVD) via antagonism of both IL-1 and LPS-mediated catabolic activity using in vitro and ex vivo analyses. Specifically, we demonstrate the biological counteraction of LfcinB against IL-1 and LPS-mediated proteoglycan (PG) depletion, matrix-degrading enzyme production and enzyme activity in long-term (alginate beads) and short-term (monolayer) culture models using bovine and human nucleus pulposus (NP) cells. LfcinB significantly attenuates the IL-1 and LPS-mediated suppression of PG production and synthesis, and thus restores PG accumulation and pericellular matrix formation. Simultaneously, LfcinB antagonizes catabolic factor mediated induction of multiple cartilage-degrading enzymes, including MMP-1, MMP-3, MMP-13, ADAMTS-4, and ADAMTS-5, in bovine NP cells at both mRNA and protein levels. LfcinB also suppresses the catabolic factor-induced stimulation of oxidative and inflammatory factors such as iNOS, IL-6, and toll-like receptor-2 (TLR-2) and TLR-4. Finally, the ability of LfcinB to antagonize IL-1 and LPS-mediated suppression of PG is upheld in an en bloc intradiscal microinjection model followed by ex vivo organ culture using both mouse and rabbit IVD tissue, suggesting a potential therapeutic benefit of LfcinB on degenerative disc disease in the future. PMID:23460134

Lactoferricin mediates anti-inflammatory and anti-catabolic effects via inhibition of IL-1 and LPS activity in the intervertebral disc.

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Kim, Jae-Sung; Ellman, Michael B; Yan, Dongyao; An, Howard S; Kc, Ranjan; Li, Xin; Chen, Di; Xiao, Guozhi; Cs-Szabo, Gabriella; Hoskin, David W; Buechter, Doug D; Van Wijnen, Andre J; Im, Hee-Jeong

2013-09-01

The catabolic cytokine interleukin-1 (IL-1) and endotoxin lipopolysaccharide (LPS) are well-known inflammatory mediators involved in degenerative disc disease, and inhibitors of IL-1 and LPS may potentially be used to slow or prevent disc degeneration in vivo. Here, we elucidate the striking anti-catabolic and anti-inflammatory effects of bovine lactoferricin (LfcinB) in the intervertebral disc (IVD) via antagonism of both IL-1 and LPS-mediated catabolic activity using in vitro and ex vivo analyses. Specifically, we demonstrate the biological counteraction of LfcinB against IL-1 and LPS-mediated proteoglycan (PG) depletion, matrix-degrading enzyme production, and enzyme activity in long-term (alginate beads) and short-term (monolayer) culture models using bovine and human nucleus pulposus (NP) cells. LfcinB significantly attenuates the IL-1 and LPS-mediated suppression of PG production and synthesis, and thus restores PG accumulation and pericellular matrix formation. Simultaneously, LfcinB antagonizes catabolic factor mediated induction of multiple cartilage-degrading enzymes, including MMP-1, MMP-3, MMP-13, ADAMTS-4, and ADAMTS-5, in bovine NP cells at both mRNA and protein levels. LfcinB also suppresses the catabolic factor-induced stimulation of oxidative and inflammatory factors such as iNOS, IL-6, and toll-like receptor-2 (TLR-2) and TLR-4. Finally, the ability of LfcinB to antagonize IL-1 and LPS-mediated suppression of PG is upheld in an en bloc intradiscal microinjection model followed by ex vivo organ culture using both mouse and rabbit IVD tissue, suggesting a potential therapeutic benefit of LfcinB on degenerative disc disease in the future. Copyright © 2013 Wiley Periodicals, Inc.

Intrinsic and induced isoproturon catabolic activity in dissimilar soils and soils under dissimilar land use.

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Reid, Brian J; Papanikolaou, Niki D; Wilcox, Ronah K

2005-02-01

The catabolic activity with respect to the systemic herbicide isoproturon was determined in soil samples by (14)C-radiorespirometry. The first experiment assessed levels of intrinsic catabolic activity in soil samples that represented three dissimilar soil series under arable cultivation. Results showed average extents of isoproturon mineralisation (after 240 h assay time) in the three soil series to be low. A second experiment assessed the impact of addition of isoproturon (0.05 microg kg(-1)) into these soils on the levels of catabolic activity following 28 days of incubation. Increased catabolic activity was observed in all three soils. A third experiment assessed levels of intrinsic catabolic activity in soil samples representing a single soil series managed under either conventional agricultural practice (including the use of isoproturon) or organic farming practice (with no use of isoproturon). Results showed higher (and more consistent) levels of isoproturon mineralisation in the soil samples collected from conventional land use. The final experiment assessed the impact of isoproturon addition on the levels of inducible catabolic activity in these soils. The results showed no significant difference in the case of the conventional farm soil samples while the induction of catabolic activity in the organic farm soil samples was significant.

Metabolic reconstructions identify plant 3-methylglutaconyl-CoA hydratase that is crucial for branched-chain amino acid catabolism in mitochondria.

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Latimer, Scott; Li, Yubing; Nguyen, Thuong T H; Soubeyrand, Eric; Fatihi, Abdelhak; Elowsky, Christian G; Block, Anna; Pichersky, Eran; Basset, Gilles J

2018-05-09

The proteinogenic branched-chain amino acids (BCAAs) leucine, isoleucine and valine are essential nutrients for mammals. In plants, BCAAs double as alternative energy sources when carbohydrates become limiting, the catabolism of BCAAs providing electrons to the respiratory chain and intermediates to the tricarboxylic acid cycle. Yet, the actual architecture of the degradation pathways of BCAAs is not well understood. In this study, gene network modeling in Arabidopsis and rice, and plant-prokaryote comparative genomics detected candidates for 3-methylglutaconyl-CoA hydratase (4.2.1.18), one of the missing plant enzymes of leucine catabolism. Alignments of these protein candidates sampled from various spermatophytes revealed non-homologous N-terminal extensions that are lacking in their bacterial counterparts, and green fluorescent protein-fusion experiments demonstrated that the Arabidopsis protein, product of gene At4g16800, is targeted to mitochondria. Recombinant At4g16800 catalyzed the dehydration of 3-hydroxymethylglutaryl-CoA into 3-methylglutaconyl-CoA, and displayed kinetic features similar to those of its prokaryotic homolog. When at4g16800 knockout plants were subjected to dark-induced carbon starvation, their rosette leaves displayed accelerated senescence as compared to control plants, and this phenotype was paralleled by a marked increase in the accumulation of free and total leucine, isoleucine and valine. The seeds of the at4g16800 mutant showed a similar accumulation of free BCAAs. These data suggest that 3-methylglutaconyl-CoA hydratase is not solely involved in the degradation of leucine, but is also a significant contributor to that of isoleucine and valine. Furthermore, evidence is shown that unlike the situation observed in Trypanosomatidae, leucine catabolism does not contribute to the formation of the terpenoid precursor mevalonate. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights

Identification of the First Riboflavin Catabolic Gene Cluster Isolated from Microbacterium maritypicum G10*

OpenAIRE

Xu, Hui; Chakrabarty, Yindrila; Philmus, Benjamin; Mehta, Angad P.; Bhandari, Dhananjay; Hohmann, Hans-Peter; Begley, Tadhg P.

2016-01-01

Riboflavin is a common cofactor, and its biosynthetic pathway is well characterized. However, its catabolic pathway, despite intriguing hints in a few distinct organisms, has never been established. This article describes the isolation of a Microbacterium maritypicum riboflavin catabolic strain, and the cloning of the riboflavin catabolic genes. RcaA, RcaB, RcaD, and RcaE were overexpressed and biochemically characterized as riboflavin kinase, riboflavin reductase, ribokinase, and riboflavin ...

Catabolic Processes in Cardiosurgical Patients

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V. V. Lomivorotov

2007-01-01

Full Text Available Objective: to evaluate catabolic and anabolic processes in cardiosurgical patients during heart operations under extracorporeal circulation.Subjects and methods. Seventy-one patients with coronary heart disease (CHD and acquired cardiac defects (ACD, who had been operated on under extracorporeal circulation, were examined. The plasma levels of cortisol, adrenaline, insulin, growth hormone, and albumin were measured. For determination of daily nitrogen excretion, blood and diurnal urine were sampled at the following stages: 1 before surgery; 2 postoperative (PO day 1; 3 PO day 3; 4 PO day 7; 5 PO day 14; 6 PO day 21.Results. The preoperative daily nitrogen excretion in CHD patients was 10.4±1.0 g/day. By PO day 3, there was a significant increase in nitrogen excretion by 66%, up to 17.3±1.6 g/day (p<0.01. In ACD patients, the baseline daily urinary nitrogen excretion was 11.9±1.7 g/day. By PO day 3, there was a 1.4-fold increase in this index — up to 16.3±2.0 g/day. Daily nitrogen excretion significantly increased up to 17.1±1.2 g/day by the end of the first PO week (p<0.05, by exceeding the baseline values by 44%. Nitrogen excretion peaked by the end of PO days 14 (17.2±1.6 g/day (p<0.05. By hospital discharge, nitrogen excretion was 23% greater than its baseline preoperative level (p>0.05. In cardiosurgical patients, an increase in daily nitrogen excretion occurred with the elevated concentrations of the stress hormones cortisol and adrenaline.Conclusion. The magnitude of catabolic reactions after cardiosurgical interventions depends on the type of cardiac disease. In patients with CHD, the maximum catabolic reactions were recorded on PO day 3 whereas in those with ACD, they continued within three weeks postoperatively.  

The anti-catabolic role of bovine lactoferricin in cartilage.

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Ahmadinia, Kasra; Yan, Dongyao; Ellman, Michael; Im, Hee-Jeong

2013-10-01

Bovine lactoferricin (LfcinB) is a multifunctional peptide derived from bovine lactoferrin that demonstrates antibacterial, antifungal, antiviral, antitumor, and immunomodulatory activities. Recently, studies have focused on the anti-catabolic and anti-inflammatory potential of LfcinB. LfcinB is able to modulate the effects cytokines such as IL-1 and fibroblast growth factor 2 as well as promote specific cartilage anabolic factors. These properties are particularly important in maintaining cartilage homeostasis and preventing a catabolic state, which leads to clinical pathology. This review focuses on the recent literature elucidating the role of LfcinB in preventing cartilage degradation.

Complete topology inversion can be part of normal membrane protein biogenesis.

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Woodall, Nicholas B; Hadley, Sarah; Yin, Ying; Bowie, James U

2017-04-01

The topology of helical membrane proteins is generally defined during insertion of the transmembrane helices, yet it is now clear that it is possible for topology to change under unusual circumstances. It remains unclear, however, if topology reorientation is part of normal biogenesis. For dual topology dimer proteins such as the multidrug transporter EmrE, there may be evolutionary pressure to allow topology flipping so that the populations of both orientations can be equalized. We previously demonstrated that when EmrE is forced to insert in a distorted topology, topology flipping of the first transmembrane helix can occur during translation. Here, we show that topological malleability also extends to the C-terminal helix and that even complete topology inversion of the entire EmrE protein can occur after the full protein is translated and inserted. Thus, topology rearrangements are possible during normal biogenesis. Wholesale topology flipping is remarkable given the physical constraints of the membrane and expands the range of possible membrane protein folding pathways, both productive and detrimental. © 2017 The Protein Society.

Tyrosine biosynthesis, metabolism, and catabolism in plants.

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Schenck, Craig A; Maeda, Hiroshi A

2018-05-01

L-Tyrosine (Tyr) is an aromatic amino acid (AAA) required for protein synthesis in all organisms, but synthesized de novo only in plants and microorganisms. In plants, Tyr also serves as a precursor of numerous specialized metabolites that have diverse physiological roles as electron carriers, antioxidants, attractants, and defense compounds. Some of these Tyr-derived plant natural products are also used in human medicine and nutrition (e.g. morphine and vitamin E). While the Tyr biosynthesis and catabolic pathways have been extensively studied in microbes and animals, respectively, those of plants have received much less attention until recently. Accumulating evidence suggest that the Tyr biosynthetic pathways differ between microbes and plants and even within the plant kingdom, likely to support the production of lineage-specific plant specialized metabolites derived from Tyr. The interspecies variations of plant Tyr pathway enzymes can now be used to enhance the production of Tyr and Tyr-derived compounds in plants and other synthetic biology platforms. Copyright © 2018 Elsevier Ltd. All rights reserved.

Conversion of leucine to β‐hydroxy‐β‐methylbutyrate by α‐keto isocaproate dioxygenase is required for a potent stimulation of protein synthesis in L6 rat myotubes

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Vílchez, José D.; Salto, Rafael; Manzano, Manuel; Sevillano, Natalia; Campos, Nefertiti; Argilés, Josep M.; Rueda, Ricardo; López‐Pedrosa, José M.

2015-01-01

Abstract Background L‐Leu and its metabolite β‐hydroxy‐β‐methylbutyrate (HMB) stimulate muscle protein synthesis enhancing the phosphorylation of proteins that regulate anabolic signalling pathways. Alterations in these pathways are observed in many catabolic diseases, and HMB and L‐Leu have proven their anabolic effects in in vivo and in vitro models. The aim of this study was to compare the anabolic effects of L‐Leu and HMB in myotubes grown in the absence of any catabolic stimuli. Methods Studies were conducted in vitro using rat L6 myotubes under normal growth conditions (non‐involving L‐Leu‐deprived conditions). Protein synthesis and mechanistic target of rapamycin signalling pathway were determined. Results Only HMB was able to increase protein synthesis through a mechanism that involves the phosphorylation of the mechanistic target of rapamycin as well as its downstream elements, pS6 kinase, 4E binding protein‐1, and eIF4E. HMB was significantly more effective than L‐Leu in promoting these effects through an activation of protein kinase B/Akt. Because the conversion of L‐Leu to HMB is limited in muscle, L6 cells were transfected with a plasmid that codes for α‐keto isocaproate dioxygenase, the key enzyme involved in the catabolic conversion of α‐keto isocaproate into HMB. In these transfected cells, L‐Leu was able to promote protein synthesis and mechanistic target of rapamycin regulated pathway activation equally to HMB. Additionally, these effects of leucine were reverted to a normal state by mesotrione, a specific inhibitor of α‐keto isocaproate dioxygenase. Conclusion Our results suggest that HMB is an active L‐Leu metabolite able to maximize protein synthesis in skeletal muscle under conditions, in which no amino acid deprivation occurred. It may be proposed that supplementation with HMB may be very useful to stimulate protein synthesis in wasting conditions associated with chronic diseases, such as cancer or

Insights into the evolution of sialic acid catabolism among bacteria

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Almagro-Moreno Salvador

2009-05-01

Full Text Available Abstract Background Sialic acids comprise a family of nine-carbon amino sugars that are prevalent in mucus rich environments. Sialic acids from the human host are used by a number of pathogens as an energy source. Here we explore the evolution of the genes involved in the catabolism of sialic acid. Results The cluster of genes encoding the enzymes N-acetylneuraminate lyase (NanA, epimerase (NanE, and kinase (NanK, necessary for the catabolism of sialic acid (the Nan cluster, are confined 46 bacterial species, 42 of which colonize mammals, 33 as pathogens and 9 as gut commensals. We found a putative sialic acid transporter associated with the Nan cluster in most species. We reconstructed the phylogenetic history of the NanA, NanE, and NanK proteins from the 46 species and compared them to the species tree based on 16S rRNA. Within the NanA phylogeny, Gram-negative and Gram-positive bacteria do not form distinct clades. NanA from Yersinia and Vibrio species was most closely related to the NanA clade from eukaryotes. To examine this further, we reconstructed the phylogeny of all NanA homologues in the databases. In this analysis of 83 NanA sequences, Bacteroidetes, a human commensal group formed a distinct clade with Verrucomicrobia, and branched with the Eukaryotes and the Yersinia/Vibrio clades. We speculate that pathogens such as V. cholerae may have acquired NanA from a commensal aiding their colonization of the human gut. Both the NanE and NanK phylogenies more closely represented the species tree but numerous incidences of incongruence are noted. We confirmed the predicted function of the sialic acid catabolism cluster in members the major intestinal pathogens Salmonella enterica, Vibrio cholerae, V. vulnificus, Yersinia enterocolitica and Y. pestis. Conclusion The Nan cluster among bacteria is confined to human pathogens and commensals conferring them the ability to utilize a ubiquitous carbon source in mucus rich surfaces of the human body

Involvement of Phosphatidylinositol 3-kinase in the regulation of proline catabolism in Arabidopsis thaliana

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Anne-Sophie eLeprince

2015-01-01

Full Text Available Plant adaptation to abiotic stresses such as drought and salinity involves complex regulatory processes. Deciphering the signalling components that are involved in stress signal transduction and cellular responses is of importance to understand how plants cope with salt stress. Accumulation of osmolytes such as proline is considered to participate in the osmotic adjustment of plant cells to salinity. Proline accumulation results from a tight regulation between its biosynthesis and catabolism. Lipid signal components such as phospholipases C and D have previously been shown to be involved in the regulation of proline metabolism in Arabidopsis thaliana. In this study, we demonstrate that proline metabolism is also regulated by class-III Phosphatidylinositol 3-kinase (PI3K, VPS34, which catalyses the formation of phosphatidylinositol 3-phosphate (PI3P from phosphatidylinositol. Using pharmacological and biochemical approaches, we show that the PI3K inhibitor, LY294002, affects PI3P levels in vivo and that it triggers a decrease in proline accumulation in response to salt treatment of A. thaliana seedlings. The lower proline accumulation is correlated with a lower transcript level of Pyrroline-5-carboxylate synthetase 1 biosynthetic enzyme and higher transcript and protein levels of Proline dehydrogenase 1 (ProDH1, a key-enzyme in proline catabolism. We also found that the ProDH1 expression is induced in a pi3k-hemizygous mutant, further demonstrating that PI3K is involved in the regulation of proline catabolism through transcriptional regulation of ProDH1. A broader metabolomic analysis indicates that LY294002 also reduced other metabolites, such as hydrophobic and aromatic amino acids and sugars like raffinose.

Comparative genomic analysis of isoproturon-mineralizing sphingomonads reveals the isoproturon catabolic mechanism.

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Yan, Xin; Gu, Tao; Yi, Zhongquan; Huang, Junwei; Liu, Xiaowei; Zhang, Ji; Xu, Xihui; Xin, Zhihong; Hong, Qing; He, Jian; Spain, Jim C; Li, Shunpeng; Jiang, Jiandong

2016-12-01

The worldwide use of the phenylurea herbicide, isoproturon (IPU), has resulted in considerable concern about its environmental fate. Although many microbial metabolites of IPU are known and IPU-mineralizing bacteria have been isolated, the molecular mechanism of IPU catabolism has not been elucidated yet. In this study, complete genes that encode the conserved IPU catabolic pathway were revealed, based on comparative analysis of the genomes of three IPU-mineralizing sphingomonads and subsequent experimental validation. The complete genes included a novel hydrolase gene ddhA, which is responsible for the cleavage of the urea side chain of the IPU demethylated products; a distinct aniline dioxygenase gene cluster adoQTA1A2BR, which has a broad substrate range; and an inducible catechol meta-cleavage pathway gene cluster adoXEGKLIJC. Furthermore, the initial mono-N-demethylation genes pdmAB were further confirmed to be involved in the successive N-demethylation of the IPU mono-N-demethylated product. These IPU-catabolic genes were organized into four transcription units and distributed on three plasmids. They were flanked by multiple mobile genetic elements and highly conserved among IPU-mineralizing sphingomonads. The elucidation of the molecular mechanism of IPU catabolism will enhance our understanding of the microbial mineralization of IPU and provide insights into the evolutionary scenario of the conserved IPU-catabolic pathway. © 2016 The Authors. Environmental Microbiology published by Society for Applied Microbiology and John Wiley & Sons Ltd.

Differentially expressed proteins among normal cervix, cervical intraepithelial neoplasia and cervical squamous cell carcinoma.

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Zhao, Q; He, Y; Wang, X-L; Zhang, Y-X; Wu, Y-M

2015-08-01

To explore the differentially expressed proteins in normal cervix, cervical intraepithelial neoplasia (CIN) and cervical squamous cell carcinoma (CSCC) tissues by differential proteomics technique. Cervical tissues (including normal cervix, CIN and CSCC) were collected in Department of Gynecologic Oncology of Beijing Obstetrics and Gynecology Hospital. Two-dimensional fluorescence difference in gel electrophoresis (2-D DIGE) and DeCyder software were used to detect the differentially expressed proteins. Matrix-assisted laser desorption/ionization-time-of-flight tandem mass spectrometry (MALDI-TOF/TOF MS) was used to identify the differentially expressed proteins. Western blot (WB) and immunohistochemistry (IHC) were performed to validate the expressions of selected proteins among normal cervix, CIN and CSCC. 2-D DIGE images with high resolution and good repeatability were obtained. Forty-six differentially expressed proteins (27 up-regulated and 19 down-regulated) were differentially expressed among the normal cervix, CIN and CSCC. 26 proteins were successfully identified by MALDI-TOF/TOF MS. S100A9 (S100 calcium-binding protein A9) was the most significantly up-regulated protein. Eukaryotic elongation factor 1-alpha-1 (eEF1A1) was the most significantly down-regulated protein. Pyruvate kinase isozymes M2 (PKM2) was both up-regulated and down-regulated. The results of WB showed that with the increase in the severity of cervical lesions, the expression of S100A9 protein was significantly increased among the three groups (P = 0.010). The expression of eEF1A1 was reduced but without significant difference (P = 0.861). The expression of PKM2 was significantly reduced (P = 0.000). IHC showed that protein S100A9 was mainly expressed in the cytoplasm, and its positive expression rate was 20.0 % in normal cervix, 70.0 % in CIN and 100.0 % in CSCC, with a significant difference among them (P = 0.006). eEF1A1 was mainly expressed in the cell plasma, and its

Comparative Investigation of Normal Modes and Molecular Dynamics of Hepatitis C NS5B Protein

International Nuclear Information System (INIS)

Asafi, M S; Tekpinar, M; Yildirim, A

2016-01-01

Understanding dynamics of proteins has many practical implications in terms of finding a cure for many protein related diseases. Normal mode analysis and molecular dynamics methods are widely used physics-based computational methods for investigating dynamics of proteins. In this work, we studied dynamics of Hepatitis C NS5B protein with molecular dynamics and normal mode analysis. Principal components obtained from a 100 nanoseconds molecular dynamics simulation show good overlaps with normal modes calculated with a coarse-grained elastic network model. Coarse-grained normal mode analysis takes at least an order of magnitude shorter time. Encouraged by this good overlaps and short computation times, we analyzed further low frequency normal modes of Hepatitis C NS5B. Motion directions and average spatial fluctuations have been analyzed in detail. Finally, biological implications of these motions in drug design efforts against Hepatitis C infections have been elaborated. (paper)

Detection and Isolation of Novel Rhizopine-Catabolizing Bacteria from the Environment

OpenAIRE

Gardener, Brian B. McSpadden; de Bruijn, Frans J.

1998-01-01

Microbial rhizopine-catabolizing (Moc) activity was detected in serial dilutions of soil and rhizosphere washes. The activity observed generally ranged between 106 and 107 catabolic units per g, and the numbers of nonspecific culture-forming units were found to be approximately 10 times higher. A diverse set of 37 isolates was obtained by enrichment on scyllo-inosamine-containing media. However, none of the bacteria that were isolated were found to contain DNA sequences homologous to the know...

Hyperglucagonemia during insulin deficiency accelerates protein catabolism

International Nuclear Information System (INIS)

Nair, K.S.; Halliday, D.; Matthews, D.E.; Welle, S.L.

1987-01-01

Hyperglucagonemia coexists with insulin deficiency or insulin resistance in many conditions where urinary nitrogen excretion is increased, but the precise role of glucagon in these conditions is controversial. The purpose of this study was to evaluate the effect of hyperglucagonemia on protein metabolism in insulin-deficient subjects. The authors used the stable isotope of an essential amino acid (L-[1- 13 C]leucine) as a tracer of in vivo protein metabolism. A combined deficiency of insulin and glucagon was induced by intravenous infusion of somatostatin. Hyperglucagonemia and hypoinsulinemia were induced by infusions of somatostatin and glucagon. When somatostatin alone was infused leucine flux increased, indicating a 6-17% increase in proteolysis. When somatostatin and glucagon were infused, leucine flux increased, indicating a 12-32% increase in proteolysis. The increase in leucine flux during the infusion of somatostatin and glucagon was higher than the increase during infusion of somatostatin alone. Somatostatin alone did not change leucine oxidation, whereas the somatostatin plus glucagon increased leucine oxidation 100%. They conclude that hyperglucagonemia accelerated proteolysis and leucine oxidation in insulin-deficient humans

Platelet-Rich Plasma Increases the Levels of Catabolic Molecules and Cellular Dedifferentiation in the Meniscus of a Rabbit Model

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Hye-Rim Lee

2016-01-01

Full Text Available Despite the susceptibility to frequent intrinsic and extrinsic injuries, especially in the inner zone, the meniscus does not heal spontaneously owing to its poor vascularity. In this study, the effect of platelet-rich plasma (PRP, containing various growth factors, on meniscal mechanisms was examined under normal and post-traumatic inflammatory conditions. Isolated primary meniscal cells of New Zealand white (NZW rabbits were incubated for 3, 10, 14 and 21 days with PRP(−, 10% PRP (PRP(+, IL(+ or IL(+PRP(+. The meniscal cells were collected and examined using reverse-transcription polymerase chain reaction (RT-PCR. Culture media were examined by immunoblot analyses for matrix metalloproteinases (MMP catabolic molecules. PRP containing growth factors improved the cellular viability of meniscal cells in a concentration-dependent manner at Days 1, 4 and 7. However, based on RT-PCR, meniscal cells demonstrated dedifferentiation, along with an increase in type I collagen in the PRP(+ and in IL(+PRP(+. In PRP(+, the aggrecan expression levels were lower than in the PRP(− until Day 21. The protein levels of MMP-1 and MMP-3 were higher in each PRP group, i.e., PRP(+ and IL(+PRP(+, at each culture time. A reproducible 2-mm circular defect on the meniscus of NZW rabbit was used to implant fibrin glue (control or PRP in vivo. After eight weeks, the lesions in the control and PRP groups were occupied with fibrous tissue, but not with meniscal cells. This study shows that PRP treatment of the meniscus results in an increase of catabolic molecules, especially those related to IL-1α-induced inflammation, and that PRP treatment for an in vivo meniscus injury accelerates fibrosis, instead of meniscal cartilage.

Amino acid catabolism by Lactobacillus helveticus in cheese

DEFF Research Database (Denmark)

Kananen, Soila Kaarina

Amino acid catabolism is the final step in the conversion of caseins to flavour compounds and a part of a complex combination of biochemical pathways in cheese flavour formation. Lactobacillus helveticus is a thermophilic lactic acid bacterium that is used in cheese manufacture as a primary starter...... culture or as an adjunct culture. It has shown high proteolytic activities in conversion of caseins to peptides and further to amino acids and flavour compounds. Better understanding of the enzyme activity properties and the influence of different properties on final cheese flavour is favourable...... for developing new cheese products with enhanced flavour. The aim of this Ph.D. study was to investigate the importance of strain variation of Lb. helveticus in relation flavour formation in cheese related to amino acid catabolism. Aspects of using Lb. helveticus as starter as well as adjunct culture in cheese...

Effect of 60Co-irradiation on normal and low protein diet fed rat brain

International Nuclear Information System (INIS)

Hasan, S.S.; Habibullah, M.

1980-01-01

The effect of whole-body irradiation (Co-60) on the brain tissue in Holtzmann strain adult male rats was studied. Two doses of irradiation (450 R,950 R) were tried on animals which were fed on normal as well as low protein diets over a period of 10 generations. In the normal rats, 450 R initially caused a lowered total protein. DNA and RNA content in the brain. After 7 days a tendency towards normalcy was observed. In the 950 R irradiated normal rats the diminution of protein content appeared irreversible. In malnourished 450 R irradiated rats, the protein content rose less steeply over the 7 days of observation. A higher dose of 950 R enhanced this effect on protein and also lowered the DNA content on day 5. The RNA content in the 950 R group with malnutrition showed a marked increase towards or beyond control perhaps as an expression of uncoupled feedback control. The paper gives evidence that protein deficiency may interfere with cellular regeneration in irradiated brain. (orig.) [de

Competition between pentoses and glucose during uptake and catabolism in recombinant Saccharomyces cerevisiae

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Subtil Thorsten

2012-03-01

Full Text Available Abstract Background In mixed sugar fermentations with recombinant Saccharomyces cerevisiae strains able to ferment D-xylose and L-arabinose the pentose sugars are normally only utilized after depletion of D-glucose. This has been attributed to competitive inhibition of pentose uptake by D-glucose as pentose sugars are taken up into yeast cells by individual members of the yeast hexose transporter family. We wanted to investigate whether D-glucose inhibits pentose utilization only by blocking its uptake or also by interfering with its further metabolism. Results To distinguish between inhibitory effects of D-glucose on pentose uptake and pentose catabolism, maltose was used as an alternative carbon source in maltose-pentose co-consumption experiments. Maltose is taken up by a specific maltose transport system and hydrolyzed only intracellularly into two D-glucose molecules. Pentose consumption decreased by about 20 - 30% during the simultaneous utilization of maltose indicating that hexose catabolism can impede pentose utilization. To test whether intracellular D-glucose might impair pentose utilization, hexo-/glucokinase deletion mutants were constructed. Those mutants are known to accumulate intracellular D-glucose when incubated with maltose. However, pentose utilization was not effected in the presence of maltose. Addition of increasing concentrations of D-glucose to the hexo-/glucokinase mutants finally completely blocked D-xylose as well as L-arabinose consumption, indicating a pronounced inhibitory effect of D-glucose on pentose uptake. Nevertheless, constitutive overexpression of pentose-transporting hexose transporters like Hxt7 and Gal2 could improve pentose consumption in the presence of D-glucose. Conclusion Our results confirm that D-glucose impairs the simultaneous utilization of pentoses mainly due to inhibition of pentose uptake. Whereas intracellular D-glucose does not seem to have an inhibitory effect on pentose utilization

Interleukin-6 blockade raises LDL via reduced catabolism rather than via increased synthesis: a cytokine-specific mechanism for cholesterol changes in rheumatoid arthritis.

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Robertson, Jamie; Porter, Duncan; Sattar, Naveed; Packard, Chris J; Caslake, Muriel; McInnes, Iain; McCarey, David

2017-11-01

Patients with rheumatoid arthritis (RA) have reduced serum low-density lipoprotein cholesterol (LDL-c), which increases following therapeutic IL-6 blockade. We aimed to define the metabolic pathways underlying these lipid changes. In the KALIBRA study, lipoprotein kinetic studies were performed on 11 patients with severe active RA at baseline and following three intravenous infusions of the IL-6R blocker tocilizumab. The primary outcome measure was the fractional catabolic rate (FCR) of LDL. Serum total cholesterol (4.8 vs 5.7 mmol/L, p=0.003), LDL-c (2.9 vs 3.4 mmol/L, p=0.014) and high-density lipoprotein cholesterol (1.23 vs 1.52 mmol/L, p=0.006) increased following tocilizumab therapy. The LDL FCR fell from a state of hypercatabolism to a value approximating that of the normal population (0.53 vs 0.27 pools/day, p=0.006). Changes in FCR correlated tightly with changes in serum LDL-c and C-reactive protein but not Clinical Disease Activity Index. Patients with RA have low serum LDL-c due to hypercatabolism of LDL particles. IL-6 blockade normalises this catabolism in a manner associating with the acute phase response (and thus hepatic IL-6 signalling) but not with RA disease activity as measured clinically. We demonstrate that IL-6 is one of the key drivers of inflammation-driven dyslipidaemia. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

ATP-binding Cassette (ABC) Transport System Solute-binding Protein-guided Identification of Novel d-Altritol and Galactitol Catabolic Pathways in Agrobacterium tumefaciens C58*

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Wichelecki, Daniel J.; Vetting, Matthew W.; Chou, Liyushang; Al-Obaidi, Nawar; Bouvier, Jason T.; Almo, Steven C.; Gerlt, John A.

2015-01-01

Innovations in the discovery of the functions of uncharacterized proteins/enzymes have become increasingly important as advances in sequencing technology flood protein databases with an exponentially growing number of open reading frames. This study documents one such innovation developed by the Enzyme Function Initiative (EFI; U54GM093342), the use of solute-binding proteins for transport systems to identify novel metabolic pathways. In a previous study, this strategy was applied to the tripartite ATP-independent periplasmic transporters. Here, we apply this strategy to the ATP-binding cassette transporters and report the discovery of novel catabolic pathways for d-altritol and galactitol in Agrobacterium tumefaciens C58. These efforts resulted in the description of three novel enzymatic reactions as follows: 1) oxidation of d-altritol to d-tagatose via a dehydrogenase in Pfam family PF00107, a previously unknown reaction; 2) phosphorylation of d-tagatose to d-tagatose 6-phosphate via a kinase in Pfam family PF00294, a previously orphan EC number; and 3) epimerization of d-tagatose 6-phosphate C-4 to d-fructose 6-phosphate via a member of Pfam family PF08013, another previously unknown reaction. The epimerization reaction catalyzed by a member of PF08013 is especially noteworthy, because the functions of members of PF08013 have been unknown. These discoveries were assisted by the following two synergistic bioinformatics web tools made available by the Enzyme Function Initiative: the EFI-Enzyme Similarity Tool and the EFI-Genome Neighborhood Tool. PMID:26472925

Involvement of the Cra global regulatory protein in the expression of the iscRSUA operon, revealed during studies of tricarballylate catabolism in Salmonella enterica.

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Lewis, Jeffrey A; Boyd, Jeffrey M; Downs, Diana M; Escalante-Semerena, Jorge C

2009-04-01

In Salmonella enterica, tricarballylate (Tcb) catabolism requires function of TcuB, a membrane-bound protein that contains [4Fe-4S] clusters and heme. TcuB transfers electrons from reduced flavin adenine dinucleotide in the Tcb dehydrogenase (TcuA) to electron acceptors in the membrane. We recently showed that functions needed to assemble [Fe-S] clusters (i.e., the iscRSUA-hscBA-fdx operon) compensate for the lack of ApbC during growth of an apbC strain on Tcb. ApbC had been linked to [Fe-S] cluster metabolism, and we showed that an apbC strain had decreased TcuB activity. Here we report findings that expand our understanding of the regulation of expression of the iscRSUA genes in Salmonella enterica. We investigated why low levels of glucose or other saccharides restored growth of an apbC strain on Tcb. Here we report the following findings. (i) A Cra. (iv) Putative Cra binding sites are present in the regulatory region of the iscRSUA operon. (v) Cra protein binds to all three sites in the iscRSUA promoter region in a concentration-dependent fashion. To our knowledge, this is the first report of the involvement of Cra in [Fe-S] cluster assembly.

Endocannabinoid Catabolic Enzymes Play Differential Roles in Thermal Homeostasis in Response to Environmental or Immune Challenge.

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Nass, Sara R; Long, Jonathan Z; Schlosburg, Joel E; Cravatt, Benjamin F; Lichtman, Aron H; Kinsey, Steven G

2015-06-01

Cannabinoid receptor agonists, such as Δ(9)-THC, the primary active constituent of Cannabis sativa, have anti-pyrogenic effects in a variety of assays. Recently, attention has turned to the endogenous cannabinoid system and how endocannabinoids, including 2-arachidonoylglycerol (2-AG) and anandamide, regulate multiple homeostatic processes, including thermoregulation. Inhibiting endocannabinoid catabolic enzymes, monoacylglycerol lipase (MAGL) or fatty acid amide hydrolase (FAAH), elevates levels of 2-AG or anandamide in vivo, respectively. The purpose of this experiment was to test the hypothesis that endocannabinoid catabolic enzymes function to maintain thermal homeostasis in response to hypothermic challenge. In separate experiments, male C57BL/6J mice were administered a MAGL or FAAH inhibitor, and then challenged with the bacterial endotoxin lipopolysaccharide (LPS; 2 mg/kg ip) or a cold (4 °C) ambient environment. Systemic LPS administration caused a significant decrease in core body temperature after 6 h, and this hypothermia persisted for at least 12 h. Similarly, cold environment induced mild hypothermia that resolved within 30 min. JZL184 exacerbated hypothermia induced by either LPS or cold challenge, both of which effects were blocked by rimonabant, but not SR144528, indicating a CB1 cannabinoid receptor mechanism of action. In contrast, the FAAH inhibitor, PF-3845, had no effect on either LPS-induced or cold-induced hypothermia. These data indicate that unlike direct acting cannabinoid receptor agonists, which elicit profound hypothermic responses on their own, neither MAGL nor FAAH inhibitors affect normal body temperature. However, these endocannabinoid catabolic enzymes play distinct roles in thermoregulation following hypothermic challenges.

Cytoskeletal proteins in the follicular wall of normal andcystic ovaries of sows

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Fabiano J.F. de Sant'Ana

2015-02-01

Full Text Available The expression of cytoskeletal proteins was evaluated immunohistochemically in 36 normal ovaries sampled from 18 sows and 44 cystic ovaries sampled from of 22 sows, was evaluated. All sows had history of reproductive problems, such as infertility or subfertility. The immunohistochemically stained area (IHCSA was quantified through image analysis to evaluate the expression of these proteins in the follicular wall of secondary, tertiary, and cystic follicles. Cytokeratins (CK immunoreactivity was strong in the granulosa cell layer (GC and mild in the theca interna (TI and externa (TE of the normal follicles. There was severe reduction of the reaction to CK in the GC in the cystic follicles, mainly in the luteinized cysts. The immunoreactivity for vimentin was higher in the GC from normal and cystic follicles in contrast with the other follicular structures. In the luteinized cysts, the IHCSA for vimentin was significantly higher in TI and in both observed cysts, the labeling was more accentuated in TE. Immunohistochemical detection of desmin and α-SMA was restricted to the TE, without differences between the normal and cystic follicles. The results of the current study show that the development of ovarian cysts in sows is associated to changes in the expression of the cytoskeletal proteins CK and vimentin.

Protein phosphatase 2Cm is a critical regulator of branched-chain amino acid catabolism in mice and cultured cells.

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Lu, Gang; Sun, Haipeng; She, Pengxiang; Youn, Ji-Youn; Warburton, Sarah; Ping, Peipei; Vondriska, Thomas M; Cai, Hua; Lynch, Christopher J; Wang, Yibin

2009-06-01

The branched-chain amino acids (BCAA) are essential amino acids required for protein homeostasis, energy balance, and nutrient signaling. In individuals with deficiencies in BCAA, these amino acids can be preserved through inhibition of the branched-chain-alpha-ketoacid dehydrogenase (BCKD) complex, the rate-limiting step in their metabolism. BCKD is inhibited by phosphorylation of its E1alpha subunit at Ser293, which is catalyzed by BCKD kinase. During BCAA excess, phosphorylated Ser293 (pSer293) becomes dephosphorylated through the concerted inhibition of BCKD kinase and the activity of an unknown intramitochondrial phosphatase. Using unbiased, proteomic approaches, we have found that a mitochondrial-targeted phosphatase, PP2Cm, specifically binds the BCKD complex and induces dephosphorylation of Ser293 in the presence of BCKD substrates. Loss of PP2Cm completely abolished substrate-induced E1alpha dephosphorylation both in vitro and in vivo. PP2Cm-deficient mice exhibited BCAA catabolic defects and a metabolic phenotype similar to the intermittent or intermediate types of human maple syrup urine disease (MSUD), a hereditary disorder caused by defects in BCKD activity. These results indicate that PP2Cm is the endogenous BCKD phosphatase required for nutrient-mediated regulation of BCKD activity and suggest that defects in PP2Cm may be responsible for a subset of human MSUD.

Hepatic Fatty Acid Oxidation Restrains Systemic Catabolism during Starvation

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Jieun Lee

2016-06-01

Full Text Available The liver is critical for maintaining systemic energy balance during starvation. To understand the role of hepatic fatty acid β-oxidation on this process, we generated mice with a liver-specific knockout of carnitine palmitoyltransferase 2 (Cpt2L−/−, an obligate step in mitochondrial long-chain fatty acid β-oxidation. Fasting induced hepatic steatosis and serum dyslipidemia with an absence of circulating ketones, while blood glucose remained normal. Systemic energy homeostasis was largely maintained in fasting Cpt2L−/− mice by adaptations in hepatic and systemic oxidative gene expression mediated in part by Pparα target genes including procatabolic hepatokines Fgf21, Gdf15, and Igfbp1. Feeding a ketogenic diet to Cpt2L−/− mice resulted in severe hepatomegaly, liver damage, and death with a complete absence of adipose triglyceride stores. These data show that hepatic fatty acid oxidation is not required for survival during acute food deprivation but essential for constraining adipocyte lipolysis and regulating systemic catabolism when glucose is limiting.

Estradiol stimulates glycogen synthesis whereas progesterone promotes glycogen catabolism in the uterus of the American mink (Neovison vison).

Science.gov (United States)

Bowman, Kole; Rose, Jack

2017-01-01

Glycogen synthesis by mink uterine glandular and luminal epithelia (GE and LE) is stimulated by estradiol (E 2 ) during estrus. Subsequently, the glycogen deposits are mobilized to near completion to meet the energy requirements of pre-embryonic development and implantation by as yet undetermined mechanisms. We hypothesized that progesterone (P 4 ) was responsible for catabolism of uterine glycogen reserves as one of its actions to ensure reproductive success. Mink were treated with E 2 , P 4 or vehicle (controls) for 3 days and uteri collected 24 h (E 2 , P 4 and vehicle) and 96 h (E 2 ) later. To evaluate E 2 priming, mink were treated with E 2 for 3 days, then P 4 for an additional 3 days (E 2 →P 4 ) and uteri collected 24 h later. Percent glycogen content of uterine epithelia was greater at E 2 + 96 h (GE = 5.71 ± 0.55; LE = 11.54 ± 2.32) than E 2 +24 h (GE = 3.63 ± 0.71; LE = 2.82 ± 1.03), and both were higher than controls (GE = 0.27 ± 0.15; LE = 0.54 ± 0.30; P glycogen content (GE = 0.61 ± 0.16; LE = 0.51 ± 0.13), to levels not different from controls, while concomitantly increasing catabolic enzyme (glycogen phosphorylase m and glucose-6-phosphatase) gene expression and amount of phospho-glycogen synthase protein (inactive) in uterine homogenates. Interestingly, E 2 →P 4 increased glycogen synthase 1 messenger RNA (mRNA) and hexokinase 1mRNA and protein. Our findings suggest to us that while E 2 promotes glycogen accumulation by the mink uterus during estrus and pregnancy, it is P 4 that induces uterine glycogen catabolism, releasing the glucose that is essential to support pre-embryonic survival and implantation. © 2016 Japanese Society of Animal Science.

Study of nuclear proteins in normal and xeroderma pigmentosum lymphoblastoid cells

International Nuclear Information System (INIS)

Amari, N.M.B.

1985-01-01

Nuclear histone and nonhistone (NHP) proteins from normal human and xeroderma pigmentosum, complementation group A (XP-A) lymphoblastoid cells were compared both qualitatively, quantitatively and for binding affinity for DNA. Histones and four NHP fractions (NHP/sub 1-4/) were isolated from purified cell nuclei. Binding affinity to [ 3 H] melanoma DNA of histones and each NHP fraction was then determined using gradient dialysis followed by a filter assay. Histones and each NHP fraction were then sub-fractionated by polyacrylamide gel electrophoresis. Densitometric scans of the separation of these proteins on the gels were qualitatively, and quantitatively analyzed and compared between the two cell lines. No qualitative or quantitative differences were observed between histones from XP-A or normal cells

Neuraminidases 3 and 4 regulate neuronal function by catabolizing brain gangliosides.

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Pan, Xuefang; De Aragão, Camila De Britto Pará; Velasco-Martin, Juan P; Priestman, David A; Wu, Harry Y; Takahashi, Kohta; Yamaguchi, Kazunori; Sturiale, Luisella; Garozzo, Domenico; Platt, Frances M; Lamarche-Vane, Nathalie; Morales, Carlos R; Miyagi, Taeko; Pshezhetsky, Alexey V

2017-08-01

Gangliosides (sialylated glycolipids) play an essential role in the CNS by regulating recognition and signaling in neurons. Metabolic blocks in processing and catabolism of gangliosides result in the development of severe neurologic disorders, including gangliosidoses manifesting with neurodegeneration and neuroinflammation. We demonstrate that 2 mammalian enzymes, neuraminidases 3 and 4, play important roles in catabolic processing of brain gangliosides by cleaving terminal sialic acid residues in their glycan chains. In neuraminidase 3 and 4 double-knockout mice, G M3 ganglioside is stored in microglia, vascular pericytes, and neurons, causing micro- and astrogliosis, neuroinflammation, accumulation of lipofuscin bodies, and memory loss, whereas their cortical and hippocampal neurons have lower rate of neuritogenesis in vitro Double-knockout mice also have reduced levels of G M1 ganglioside and myelin in neuronal axons. Furthermore, neuraminidase 3 deficiency drastically increased storage of G M2 in the brain tissues of an asymptomatic mouse model of Tay-Sachs disease, a severe human gangliosidosis, indicating that this enzyme is responsible for the metabolic bypass of β-hexosaminidase A deficiency. Together, our results provide the first in vivo evidence that neuraminidases 3 and 4 have important roles in CNS function by catabolizing gangliosides and preventing their storage in lipofuscin bodies.-Pan, X., De Britto Pará De Aragão, C., Velasco-Martin, J. P., Priestman, D. A., Wu, H. Y., Takahashi, K., Yamaguchi, K., Sturiale, L., Garozzo, D., Platt, F. M., Lamarche-Vane, N., Morales, C. R., Miyagi, T., Pshezhetsky, A. V. Neuraminidases 3 and 4 regulate neuronal function by catabolizing brain gangliosides. © FASEB.

Microbial catabolic activities are naturally selected by metabolic energy harvest rate.

Science.gov (United States)

González-Cabaleiro, Rebeca; Ofiţeru, Irina D; Lema, Juan M; Rodríguez, Jorge

2015-12-01

The fundamental trade-off between yield and rate of energy harvest per unit of substrate has been largely discussed as a main characteristic for microbial established cooperation or competition. In this study, this point is addressed by developing a generalized model that simulates competition between existing and not experimentally reported microbial catabolic activities defined only based on well-known biochemical pathways. No specific microbial physiological adaptations are considered, growth yield is calculated coupled to catabolism energetics and a common maximum biomass-specific catabolism rate (expressed as electron transfer rate) is assumed for all microbial groups. Under this approach, successful microbial metabolisms are predicted in line with experimental observations under the hypothesis of maximum energy harvest rate. Two microbial ecosystems, typically found in wastewater treatment plants, are simulated, namely: (i) the anaerobic fermentation of glucose and (ii) the oxidation and reduction of nitrogen under aerobic autotrophic (nitrification) and anoxic heterotrophic and autotrophic (denitrification) conditions. The experimentally observed cross feeding in glucose fermentation, through multiple intermediate fermentation pathways, towards ultimately methane and carbon dioxide is predicted. Analogously, two-stage nitrification (by ammonium and nitrite oxidizers) is predicted as prevailing over nitrification in one stage. Conversely, denitrification is predicted in one stage (by denitrifiers) as well as anammox (anaerobic ammonium oxidation). The model results suggest that these observations are a direct consequence of the different energy yields per electron transferred at the different steps of the pathways. Overall, our results theoretically support the hypothesis that successful microbial catabolic activities are selected by an overall maximum energy harvest rate.

Effect of /sup 60/Co-irradiation on normal and low protein diet fed rat brain

Energy Technology Data Exchange (ETDEWEB)

Hasan, S S [Garhwal Univ., Srinagar, Uttar Pradesh (India). Dept. of Zoology; Habibullah, M [Jawaharlal Nehru Univ., New Delhi (India). Neurobiology Lab.

1980-06-01

The effect of whole-body irradiation (Co-60) on the brain tissue in Holtzmann strain adult male rats was studied. Two doses of irradiation (450 R,950 R) were tried on animals which were fed on normal as well as low protein diets over a period of 10 generations. In the normal rats, 450 R initially caused a lowered total protein. DNA and RNA content in the brain. After 7 days a tendency towards normalcy was observed. In the 950 R irradiated normal rats the diminution of protein content appeared irreversible. In malnourished 450 R irradiated rats, the protein content rose less steeply over the 7 days of observation. A higher dose of 950 R enhanced this effect on protein and also lowered the DNA content on day 5. The RNA content in the 950 R group with malnutrition showed a marked increase towards or beyond control perhaps as an expression of uncoupled feedback control. The paper gives evidence that protein deficiency may interfere with cellular regeneration in irradiated brain.

Krill protein hydrolysate reduces plasma triacylglycerol level with concurrent increase in plasma bile acid level and hepatic fatty acid catabolism in high-fat fed mice

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Marie S. Ramsvik

2013-11-01

Full Text Available Background: Krill powder, consisting of both lipids and proteins, has been reported to modulate hepatic lipid catabolism in animals. Fish protein hydrolysate diets have also been reported to affect lipid metabolism and to elevate bile acid (BA level in plasma. BA interacts with a number of nuclear receptors and thus affects a variety of signaling pathways, including very low density lipoprotein (VLDL secretion. The aim of the present study was to investigate whether a krill protein hydrolysate (KPH could affect lipid and BA metabolism in mice. Method: C57BL/6 mice were fed a high-fat (21%, w/w diet containing 20% crude protein (w/w as casein (control group or KPH for 6 weeks. Lipids and fatty acid composition were measured from plasma, enzyme activity and gene expression were analyzed from liver samples, and BA was measured from plasma. Results: The effect of dietary treatment with KPH resulted in reduced levels of plasma triacylglycerols (TAG and non-esterified fatty acids (NEFAs. The KPH treated mice had also a marked increased plasma BA concentration. The increased plasma BA level was associated with induction of genes related to membrane canalicular exporter proteins (Abcc2, Abcb4 and to BA exporters to blood (Abcc3 and Abcc4. Of note, we observed a 2-fold increased nuclear farnesoid X receptor (Fxr mRNA levels in the liver of mice fed KPH. We also observed increased activity of the nuclear peroxiosme proliferator-activated receptor alpha (PPARα target gene carnitine plamitoyltransferase 2 (CPT-2. Conclusion: The KPH diet showed to influence lipid and BA metabolism in high-fat fed mice. Moreover, increased mitochondrial fatty acid oxidation and elevation of BA concentration may regulate the plasma level of TAGs and NEFAs.

Functional characterization of diverse ring-hydroxylating oxygenases and induction of complex aromatic catabolic gene clusters in Sphingobium sp. PNB

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Pratick Khara

2014-01-01

Full Text Available Sphingobium sp. PNB, like other sphingomonads, has multiple ring-hydroxylating oxygenase (RHO genes. Three different fosmid clones have been sequenced to identify the putative genes responsible for the degradation of various aromatics in this bacterial strain. Comparison of the map of the catabolic genes with that of different sphingomonads revealed a similar arrangement of gene clusters that harbors seven sets of RHO terminal components and a sole set of electron transport (ET proteins. The presence of distinctly conserved amino acid residues in ferredoxin and in silico molecular docking analyses of ferredoxin with the well characterized terminal oxygenase components indicated the structural uniqueness of the ET component in sphingomonads. The predicted substrate specificities, derived from the phylogenetic relationship of each of the RHOs, were examined based on transformation of putative substrates and their structural homologs by the recombinant strains expressing each of the oxygenases and the sole set of available ET proteins. The RHO AhdA1bA2b was functionally characterized for the first time and was found to be capable of transforming ethylbenzene, propylbenzene, cumene, p-cymene and biphenyl, in addition to a number of polycyclic aromatic hydrocarbons. Overexpression of aromatic catabolic genes in strain PNB, revealed by real-time PCR analyses, is a way forward to understand the complex regulation of degradative genes in sphingomonads.

Sorbitol-modified hyaluronic acid reduces oxidative stress, apoptosis and mediators of inflammation and catabolism in human osteoarthritic chondrocytes.

Science.gov (United States)

Mongkhon, John-Max; Thach, Maryane; Shi, Qin; Fernandes, Julio C; Fahmi, Hassan; Benderdour, Mohamed

2014-08-01

Our study was designed to elucidate the precise molecular mechanisms by which sorbitol-modified hyaluronic acid (HA/sorbitol) exerts beneficial effects in osteoarthritis (OA). Human OA chondrocytes were treated with increasing doses of HA/sorbitol ± anti-CD44 antibody or with sorbitol alone and thereafter with or without interleukin-1beta (IL-1β) or hydrogen peroxide (H2O2). Signal transduction pathways and parameters related to oxidative stress, apoptosis, inflammation, and catabolism were investigated. HA/sorbitol prevented IL-1β-induced oxidative stress, as measured by reactive oxygen species, p47-NADPH oxidase phosphorylation, 4-hydroxynonenal (HNE) production and HNE-metabolizing glutathione-S-transferase A4-4 expression. Moreover, HA/sorbitol stifled IL-1β-induced metalloproteinase-13, nitric oxide (NO) and prostaglandin E2 release as well as inducible NO synthase expression. Study of the apoptosis process revealed that this gel significantly attenuated cell death, caspase-3 activation and DNA fragmentation elicited by exposure to a cytotoxic H2O2 dose. Examination of signaling pathway components disclosed that HA/sorbitol prevented IL-1β-induced p38 mitogen-activated protein kinase and nuclear factor-kappa B activation, but not that of extracellular signal-regulated kinases 1 and 2. Interestingly, the antioxidant as well as the anti-inflammatory and anti-catabolic effects of HA/sorbitol were attributed to sorbitol and HA, respectively. Altogether, our findings support a beneficial effect of HA/sorbitol in OA through the restoration of redox status and reduction of apoptosis, inflammation and catabolism involved in cartilage damage.

Taxon- and Site-Specific Melatonin Catabolism

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Rüdiger Hardeland

2017-11-01

Full Text Available Melatonin is catabolized both enzymatically and nonenzymatically. Nonenzymatic processes mediated by free radicals, singlet oxygen, other reactive intermediates such as HOCl and peroxynitrite, or pseudoenzymatic mechanisms are not species- or tissue-specific, but vary considerably in their extent. Higher rates of nonenzymatic melatonin metabolism can be expected upon UV exposure, e.g., in plants and in the human skin. Additionally, melatonin is more strongly nonenzymatically degraded at sites of inflammation. Typical products are several hydroxylated derivatives of melatonin and N1-acetyl-N2-formyl-5-methoxykynuramine (AFMK. Most of these products are also formed by enzymatic catalysis. Considerable taxon- and site-specific differences are observed in the main enzymatic routes of catabolism. Formation of 6-hydroxymelatonin by cytochrome P450 subforms are prevailing in vertebrates, predominantly in the liver, but also in the brain. In pineal gland and non-mammalian retina, deacetylation to 5-methoxytryptamine (5-MT plays a certain role. This pathway is quantitatively prevalent in dinoflagellates, in which 5-MT induces cyst formation and is further converted to 5-methoxyindole-3-acetic acid, an end product released to the water. In plants, the major route is catalyzed by melatonin 2-hydroxylase, whose product is tautomerized to 3-acetamidoethyl-3-hydroxy-5-methoxyindolin-2-one (AMIO, which exceeds the levels of melatonin. Formation and properties of various secondary products are discussed.

Age-related changes in the proteoglycans of human skin. Specific cleavage of decorin to yield a major catabolic fragment in adult skin.

Science.gov (United States)

Carrino, David A; Onnerfjord, Patrik; Sandy, John D; Cs-Szabo, Gabriella; Scott, Paul G; Sorrell, J Michael; Heinegård, Dick; Caplan, Arnold I

2003-05-09

Dramatic changes occur in skin as a function of age, including changes in morphology, physiology, and mechanical properties. Changes in extracellular matrix molecules also occur, and these changes likely contribute to the overall age-related changes in the physical properties of skin. The major proteoglycans detected in extracts of human skin are decorin and versican. In addition, adult human skin contains a truncated form of decorin, whereas fetal skin contains virtually undetectable levels of this truncated decorin. Analysis of this molecule, herein referred to as decorunt, indicates that it is a catabolic fragment of decorin rather than a splice variant. With antibody probes to the core protein, decorunt is found to lack the carboxyl-terminal portion of decorin. Further analysis by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry shows that the carboxyl terminus of decorunt is at Phe(170) of decorin. This result indicates that decorunt represents the amino-terminal 43% of the mature decorin molecule. Such a structure is inconsistent with alternative splicing of decorin and suggests that decorunt is a catabolic fragment of decorin. A neoepitope antiserum, anti-VRKVTF, was generated against the carboxyl terminus of decorunt. This antiserum does not recognize intact decorin in any skin proteoglycan sample tested on immunoblots but recognizes every sample of decorunt tested. The results with anti-VRKVTF confirm the identification of the carboxyl terminus of decorunt. Analysis of collagen binding by surface plasmon resonance indicates that the affinity of decorunt for type I collagen is 100-fold less than that of decorin. This observation correlates with the structural analysis of decorunt, in that it lacks regions of decorin previously shown to be important for interaction with type I collagen. The detection of a catabolic fragment of decorin suggests the existence of a specific catabolic pathway for this proteoglycan. Because of the

Protein catabolism and high lipid metabolism associated with long-distance exercise are revealed by plasma NMR metabolomics in endurance horses.

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Laurence Le Moyec

Full Text Available During long distance endurance races, horses undergo high physiological and metabolic stresses. The adaptation processes involve the modulation of the energetic pathways in order to meet the energy demand. The aims were to evaluate the effects of long endurance exercise on the plasma metabolomic profiles and to investigate the relationships with the individual horse performances. The metabolomic profiles of the horses were analyzed using the non-dedicated methodology, NMR spectroscopy and statistical multivariate analysis. The advantage of this method is to investigate several metabolomic pathways at the same time in a single sample. The plasmas were obtained before exercise (BE and post exercise (PE from 69 horses competing in three endurance races at national level (130-160 km. Biochemical assays were also performed on the samples taken at PE. The proton NMR spectra were compared using the supervised orthogonal projection on latent structure method according to several factors. Among these factors, the race location was not significant whereas the effect of the race exercise (sample BE vs PE of same horse was highly discriminating. This result was confirmed by the projection of unpaired samples (only BE or PE sample of different horses. The metabolomic profiles proved that protein, energetic and lipid metabolisms as well as glycoproteins content are highly affected by the long endurance exercise. The BE samples from finisher horses could be discriminated according to the racing speed based on their metabolomic lipid content. The PE samples could be discriminated according to the horse ranking position at the end of the race with lactate as unique correlated metabolite. As a conclusion, the metabolomic profiles of plasmas taken before and after the race provided a better understanding of the high energy demand and protein catabolism pathway that could expose the horses to metabolic disorders.

Molecular Characterization of the Genes pcaG and pcaH, Encoding Protocatechuate 3,4-Dioxygenase, Which Are Essential for Vanillin Catabolism in Pseudomonas sp. Strain HR199

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Overhage, Jörg; Kresse, Andreas U.; Priefert, Horst; Sommer, Horst; Krammer, Gerhard; Rabenhorst, Jürgen; Steinbüchel, Alexander

1999-01-01

Pseudomonas sp. strain HR199 is able to utilize eugenol (4-allyl-2-methoxyphenol), vanillin (4-hydroxy-3-methoxybenzaldehyde), or protocatechuate as the sole carbon source for growth. Mutants of this strain which were impaired in the catabolism of vanillin but retained the ability to utilize eugenol or protocatechuate were obtained after nitrosoguanidine mutagenesis. One mutant (SK6169) was used as recipient of a Pseudomonas sp. strain HR199 genomic library in cosmid pVK100, and phenotypic complementation was achieved with a 5.8-kbp EcoRI fragment (E58). The amino acid sequences deduced from two corresponding open reading frames (ORF) identified on E58 revealed high degrees of homology to pcaG and pcaH, encoding the two subunits of protocatechuate 3,4-dioxygenase. Three additional ORF most probably encoded a 4-hydroxybenzoate 3-hydroxylase (PobA) and two putative regulatory proteins, which exhibited homology to PcaQ of Agrobacterium tumefaciens and PobR of Pseudomonas aeruginosa, respectively. Since mutant SK6169 was also complemented by a subfragment of E58 that harbored only pcaH, this mutant was most probably lacking a functional β subunit of the protocatechuate 3,4-dioxygenase. Since this mutant was still able to grow on protocatechuate and lacked protocatechuate 4,5-dioxygenase and protocatechuate 2,3-dioxygenase, the degradation had to be catalyzed by different enzymes. Two other mutants (SK6184 and SK6190), which were also impaired in the catabolism of vanillin, were not complemented by fragment E58. Since these mutants accumulated 3-carboxy muconolactone during cultivation on eugenol, they most probably exhibited a defect in a step of the catabolic pathway following the ortho cleavage. Moreover, in these mutants cyclization of 3-carboxymuconic acid seems to occur by a syn absolute stereochemical course, which is normally only observed for cis,cis-muconate lactonization in pseudomonads. In conclusion, vanillin is degraded through the ortho-cleavage pathway

Effect of cobratoxin binding on the normal mode vibration within acetylcholine binding protein.

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Bertaccini, Edward J; Lindahl, Erik; Sixma, Titia; Trudell, James R

2008-04-01

Recent crystal structures of the acetylcholine binding protein (AChBP) have revealed surprisingly small structural alterations upon ligand binding. Here we investigate the extent to which ligand binding may affect receptor dynamics. AChBP is a homologue of the extracellular component of ligand-gated ion channels (LGICs). We have previously used an elastic network normal-mode analysis to propose a gating mechanism for the LGICs and to suggest the effects of various ligands on such motions. However, the difficulties with elastic network methods lie in their inability to account for the modest effects of a small ligand or mutation on ion channel motion. Here, we report the successful application of an elastic network normal mode technique to measure the effects of large ligand binding on receptor dynamics. The present calculations demonstrate a clear alteration in the native symmetric motions of a protein due to the presence of large protein cobratoxin ligands. In particular, normal-mode analysis revealed that cobratoxin binding to this protein significantly dampened the axially symmetric motion of the AChBP that may be associated with channel gating in the full nAChR. The results suggest that alterations in receptor dynamics could be a general feature of ligand binding.

Serum Copper and Plasma Protein Status in Normal Pregnancy

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Nushrat Noor, Nasim Jahan, Nayma Sultana

2012-12-01

Full Text Available AbstractBackground: Gradual alteration of serum copper and some plasma protein levels may occur with advancement of pregnancy, which is associated with increased maternal and infant morbidity and mortality.Objective: To observe serum copper and plasma protein levels in normal pregnant women of different trimesters in order to find out their nutritional status.Methods: This cross sectional study was carried out in the Department of Physiology, Sir Salimullah Medical College (SSMC, Dhaka, between 1st January 2010 and December 2010. Ninety normal pregnant women of different trimesters with age 20-30 years were included in the study group. They were selected from Out Patient Department of Obstetrics and Gynaecology, SSMC. Age matched 30 non-pregnant women were taken as control. Serum copper level was measured by Spectrophotometric method, serum total protein and albumin levels were estimated by standard method. Statistical analysis was done by one way ANOVA, Bonferroni and Pearson’s correlation coefficient test as applicable.Results: Serum Cu levels were significantly higher in all trimesters of pregnant women compared to control. Again, this value was significantly higher in 3rd trimester than that of in 1st and 2nd trimester and also in 2nd trimester than that of in 1st trimester. In addition, mean serum total protein level was significantly lower in 3rd trimester than control but no statistically significant difference was observed among different trimesters. Again, mean serum albumin level was significantly lower in 2nd and 3rd trimester than 1st trimester and control. In addition, serum Cu concentration showed significant positive correlation with different trimesters of gestation.Conclusion: This study reveals that hypercupremia along with hypoproteinemia occur in pregnant women from 1st to 3rd trimester of gestation. This gradual alteration of micro and macronutrients become more profound with advancement of pregnancy.

Rap G protein signal in normal and disordered lymphohematopoiesis.

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Minato, Nagahiro

2013-09-10

Rap proteins (Rap1, Rap2a, b, c) are small molecular weight GTPases of the Ras family. Rap G proteins mediate diverse cellular events such as cell adhesion, proliferation, and gene activation through various signaling pathways. Activation of Rap signal is regulated tightly by several specific regulatory proteins including guanine nucleotide exchange factors and GTPase-activating proteins. Beyond cell biological studies, increasing attempts have been made in the past decade to define the roles of Rap signal in specific functions of normal tissue systems as well as in cancer. In the immune and hematopoietic systems, Rap signal plays crucial roles in the development and function of essentially all lineages of lymphocytes and hematopoietic cells, and importantly, deregulated Rap signal may lead to unique pathological conditions depending on the affected cell types, including various types of leukemia and autoimmunity. The phenotypical studies have unveiled novel, even unexpected functional aspects of Rap signal in cells from a variety of tissues, providing potentially important clues for controlling human diseases, including malignancy. © 2013 Elsevier Inc. All rights reserved.

A role for TNFα in intervertebral disc degeneration: A non-recoverable catabolic shift

International Nuclear Information System (INIS)

Purmessur, D.; Walter, B.A.; Roughley, P.J.; Laudier, D.M.; Hecht, A.C.; Iatridis, James

2013-01-01

Highlights: ► TNFα induced catabolic changes similar to human intervertebral disc degeneration. ► The metabolic shift induced by TNFα was sustained following removal. ► TNFα induced changes suggestive of cell senescence without affecting cell viability. ► Interventions are required to stimulate anabolism and increase cell proliferation. -- Abstract: This study examines the effect of TNFα on whole bovine intervertebral discs in organ culture and its association with changes characteristic of intervertebral disc degeneration (IDD) in order to inform future treatments to mitigate the chronic inflammatory state commonly found with painful IDD. Pro-inflammatory cytokines such as TNFα contribute to disc pathology and are implicated in the catabolic phenotype associated with painful IDD. Whole bovine discs were cultured to examine cellular (anabolic/catabolic gene expression, cell viability and senescence using β-galactosidase) and structural (histology and aggrecan degradation) changes in response to TNFα treatment. Control or TNFα cultures were assessed at 7 and 21 days; the 21 day group also included a recovery group with 7 days TNFα followed by 14 days in basal media. TNFα induced catabolic and anti-anabolic shifts in the nucleus pulposus (NP) and annulus fibrosus (AF) at 7 days and this persisted until 21 days however cell viability was not affected. Data indicates that TNFα increased aggrecan degradation products and suggests increased β-galactosidase staining at 21 days without any recovery. TNFα treatment of whole bovine discs for 7 days induced changes similar to the degeneration processes that occur in human IDD: aggrecan degradation, increased catabolism, pro-inflammatory cytokines and nerve growth factor expression. TNFα significantly reduced anabolism in cultured IVDs and a possible mechanism may be associated with cell senescence. Results therefore suggest that successful treatments must promote anabolism and cell proliferation in

Catabolism and protein binding of /sup 99m/Tc pyridoxylideneglutamate

International Nuclear Information System (INIS)

Jansholt, A.L.; Krohn, K.A.; Stadalnik, R.C.; Matolo, N.M.; DeNardo, G.L.

1978-01-01

Various Tc-99m-labeled compounds have been suggested as replacements for [I-131] rose bengal for imaging of the hepatobiliary system. Among such compounds are Schiff's bases, which are tin-free Tc-chelates easily prepared by 30-min autoclaving of an equimolar mixture of pyridoxal and an amino acid at pH 8.5. We have compared the properties of several Schiff's bases, including Tc-99m pyridoxylideneglutamate (Tc-PyG) with [I-131] rose bengal. Under conditions described, Tc-PyG can be prepared free of Tc-pyridoxal and with 4 - radiochemical impurity. Blood clearance and biliary excretion were studied in three animal models and in normal human volunteers. In all animal models, Tc-PyG initially cleared from the blood more rapidly than rose bengal, but a significant amount of Tc-PyG was excreted in the urine, this in contrast to [I-131] rose bengal which was almost completely excreted through the biliary system. Species differences were observed in the degree of urinary versus biliary clearance of Tc-PyG, with significantly greater urinary excretion in dogs than in monkeys and rabbits. Replacing glutamate with other amino acids did not significantly increase the blood clearance rate or decrease urinary excretion, so that Tc-PyG appears to be at least as good as any of the others studied. Tc-PyG was only 20% bound to plasma proteins, and electrophoretic and chromatographic studies did not reveal any in vivo changes of Tc-PyG before excretion in urine or bile

BCKDK of BCAA Catabolism Cross-talking With the MAPK Pathway Promotes Tumorigenesis of Colorectal Cancer.

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Xue, Peipei; Zeng, Fanfan; Duan, Qiuhong; Xiao, Juanjuan; Liu, Lin; Yuan, Ping; Fan, Linni; Sun, Huimin; Malyarenko, Olesya S; Lu, Hui; Xiu, Ruijuan; Liu, Shaoqing; Shao, Chen; Zhang, Jianmin; Yan, Wei; Wang, Zhe; Zheng, Jianyong; Zhu, Feng

2017-06-01

Branched-chain amino acids catabolism plays an important role in human cancers. Colorectal cancer is the third most commonly diagnosed cancer in males and the second in females, and the new global incidence is over 1.2 million cases. The branched-chain α-keto acid dehydrogenase kinase (BCKDK) is a rate-limiting enzyme in branched-chain amino acids catabolism, which plays an important role in many serious human diseases. Here we investigated that abnormal branched-chain amino acids catabolism in colorectal cancer is a result of the disease process, with no role in disease initiation; BCKDK is widely expressed in colorectal cancer patients, and those patients that express higher levels of BCKDK have shorter survival times than those with lower levels; BCKDK promotes cell transformation or colorectal cancer ex vivo or in vivo. Mechanistically, BCKDK promotes colorectal cancer by enhancing the MAPK signaling pathway through direct MEK phosphorylation, rather than by branched-chain amino acids catabolism. And the process above could be inhibited by a BCKDK inhibitor, phenyl butyrate. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

BCKDK of BCAA Catabolism Cross-talking With the MAPK Pathway Promotes Tumorigenesis of Colorectal Cancer

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Peipei Xue

2017-06-01

Full Text Available Branched-chain amino acids catabolism plays an important role in human cancers. Colorectal cancer is the third most commonly diagnosed cancer in males and the second in females, and the new global incidence is over 1.2 million cases. The branched-chain α-keto acid dehydrogenase kinase (BCKDK is a rate-limiting enzyme in branched-chain amino acids catabolism, which plays an important role in many serious human diseases. Here we investigated that abnormal branched-chain amino acids catabolism in colorectal cancer is a result of the disease process, with no role in disease initiation; BCKDK is widely expressed in colorectal cancer patients, and those patients that express higher levels of BCKDK have shorter survival times than those with lower levels; BCKDK promotes cell transformation or colorectal cancer ex vivo or in vivo. Mechanistically, BCKDK promotes colorectal cancer by enhancing the MAPK signaling pathway through direct MEK phosphorylation, rather than by branched-chain amino acids catabolism. And the process above could be inhibited by a BCKDK inhibitor, phenyl butyrate.

Normal values of urine total protein- and albumin-to-creatinine ratios in term newborns.

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El Hamel, Chahrazed; Chianea, Thierry; Thon, Séverine; Lepichoux, Anne; Yardin, Catherine; Guigonis, Vincent

2017-01-01

It is important to have an accurate assessment of urinary protein when glomerulopathy or kidney injury is suspected. Currently available normal values for the neonate population have limited value, in part because they are based on small populations and obsolete creatinine assays. We have performed a prospective study with the aim to update the normal upper values of the urinary total protein-to-creatinine and albumin-to-creatinine ratios in term newborns. Urine samples were collected from 277 healthy, full-term newborns within the first 48 hours (D0-1) and between 72 and 120 h of life (D3-4). Total protein, albumin, creatinine and osmolality were measured and the upper limit of normal (upper-limit) values determined. At D0-1 and D3-4, the upper-limit values for the total protein-to-creatinine ratio were 1431 and 1205 mg/g (162 and 136 g/mol) and those for the albumin-to-creatinine ratio were 746 and 301 mg/g (84 and 34 g/mol), respectively. The upper-limit values were significantly higher at D0-1 than at D3-4 only for the albumin-to-creatinine ratio. This study determined the upper limit of normal values for urinary total protein-to-creatinine and albumin-to-creatinine ratios in the largest population of newborns studied to date. These values can therefore be considered as the most clinically relevant data currently available for the detection and diagnosis of glomerular injury in daily clinical practice in this population.

Metabolic control analysis of Aspergillus niger L-arabinose catabolism

NARCIS (Netherlands)

Groot, de M.J.L.; Prathumpai, W.; Visser, J.; Ruijter, G.J.G.

2005-01-01

A mathematical model of the L-arabinose/D-xylose catabolic pathway of Aspergillus niger was constructed based on the kinetic properties of the enzymes. For this purpose L-arabinose reductase, L-arabitol dehydrogenase and D-xylose reductase were purified using dye-affinity chromatography, and their

Effects of mercury on lysosomal protein digestion in the kidney proximal tubule

International Nuclear Information System (INIS)

Madsen, K.M.; Christensen, E.I.

1978-01-01

The effect of mercury on renal lysosomal protein digestion was studied after administration of mercury in vitro and in vivo. Mercuric chloride or methylmercury chloride was added in vitro to lysosomal enzymes isolated from normal rats, and subsequently, digestion experiments were carried out using 125 I-labeled lysozyme or cytochrome c as substrate proteins. Both mercury compounds produced a concentration-dependent inhibition of the degradation of the proteins, mercuric chloride being the strongest inhibitor. Mercuric chloride was also administered to rats in vivo for 5 to 8 months. Renal lysosomal enzymes from these animals also had a decreased ability to digest the two substrate proteins. Furthermore, the digestion of lysozyme intravenously injected into mercury-intoxicated rats was decreased in renal cortical slices incubated in vitro. Electron microscope autoradiography showed that intravenously injected labeled lysozyme was located primarily over lysosomes in proximal tubule cells 1 hour after injection in both control animals and mercury-intoxicated rats. These results suggest a decreased catabolism of low molecular weight proteins in the kidney during chronic mercury intoxication

Immunohistochemical analysis of oxidative stress and DNA repair proteins in normal mammary and breast cancer tissues

International Nuclear Information System (INIS)

Curtis, Carol D; Thorngren, Daniel L; Nardulli, Ann M

2010-01-01

During the course of normal cellular metabolism, oxygen is consumed and reactive oxygen species (ROS) are produced. If not effectively dissipated, ROS can accumulate and damage resident proteins, lipids, and DNA. Enzymes involved in redox regulation and DNA repair dissipate ROS and repair the resulting damage in order to preserve a functional cellular environment. Because increased ROS accumulation and/or unrepaired DNA damage can lead to initiation and progression of cancer and we had identified a number of oxidative stress and DNA repair proteins that influence estrogen responsiveness of MCF-7 breast cancer cells, it seemed possible that these proteins might be differentially expressed in normal mammary tissue, benign hyperplasia (BH), ductal carcinoma in situ (DCIS) and invasive breast cancer (IBC). Immunohistochemistry was used to examine the expression of a number of oxidative stress proteins, DNA repair proteins, and damage markers in 60 human mammary tissues which were classified as BH, DCIS or IBC. The relative mean intensity was determined for each tissue section and ANOVA was used to detect statistical differences in the relative expression of BH, DCIS and IBC compared to normal mammary tissue. We found that a number of these proteins were overexpressed and that the cellular localization was altered in human breast cancer tissue. Our studies suggest that oxidative stress and DNA repair proteins not only protect normal cells from the damaging effects of ROS, but may also promote survival of mammary tumor cells

Detection of catabolic genes in indigenous microbial consortia isolated from a diesel-contaminated soil

International Nuclear Information System (INIS)

Milcic-Terzic, J.; Saval, S.; Lopez-Vidal, Y.; Vrvic, M.M.

2001-01-01

Bioremediation is often used for in situ remediation of petroleum-contaminated sites. The primary focus of this study was on understanding the indigenous microbial community which can survive in contaminated environment and is responsible for the degradation. Diesel, toluene and naphthalene-degrading microbial consortia were isolated from diesel-contaminated soil by growing on selective hydrocarbon substrates. The presence and frequency of the catabolic genes responsible for aromatic hydrocarbon biodegradation (xylE, ndoB) within the isolated consortia were screened using polymerase chain reaction PCR and DNA-DNA colony hybridization. The diesel DNA-extract possessed both the xylE catabolic gene for toluene, and the nah catabolic gene for polynuclear aromatic hydrocarbon degradation. The toluene DNA-extract possessed only the xylE catabolic gene, while the naphthalene DNA-extract only the ndoB gene. Restriction enzyme analysis with HaeIII indicated similar restriction patterns for the xylE gene fragment between toluene DNA-extract and a type strain, Pseudomonas putida ATCC 23973. A substantial proportion (74%) of the colonies from the diesel-consortium possessed the xylE gene, and the ndoB gene (78%), while a minority (29%) of the toluene-consortium harbored the xylE gene. 59% of the colonies from the naphthalene-consortium had the ndoB gene, and did not have the xylE gene. These results indicate that the microbial population has been naturally enriched in organisms carrying genes for aromatic hydrocarbon degradation and that significant aromatic biodegradative potential exists at the site. Characterization of the population genotype constitutes a molecular diagnosis which permits the determination of the catabolic potential of the site to degrade the contaminant present. (author)

Parenteral structured triglyceride emulsion improves nitrogen balance and is cleared faster from the blood in moderately catabolic patients.

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Kruimel, J W; Naber, T H; van der Vliet, J A; Carneheim, C; Katan, M B; Jansen, J B

2001-01-01

Most postoperative patients lose net protein mass, which reflects loss of muscle tissue and organ function. Perioperative parenteral nutrition may reduce the loss of protein, but in general, with conventional lipid emulsions a waste of protein still remains. We compared the effects on nitrogen balance of an emulsion containing structured triglycerides, a new type of synthesized triglycerides, with an emulsion of a physical mixture of medium- and long-chain triglycerides as part of parenteral feeding in moderately catabolic patients. The first 5 days after placement of an aortic prosthesis patients received total parenteral nutrition (TPN) providing 0.2 g of nitrogen per kg body weight per day; energy requirement was calculated using Harris and Benedict's equation, adding 300 kcal per day for activity. Twelve patients were treated with the structured triglyceride emulsion and 13 patients with the emulsion of the physical mixture of medium- and long-chain triglycerides. The design was a randomized, double-blind parallel study. In the patients who completed the study, the mean cumulative nitrogen balance over the first 5 postoperative days was -8+/-2 g in 10 patients on the structured triglyceride emulsion and -21+/-4 g in 9 patients on the emulsion of the physical mixture of medium- and long-chain triglycerides; the mean difference was 13 g of nitrogen (95% confidence interval 4 to 22, p = .015) in favor of the structured triglyceride emulsion. On the first postoperative day serum triglyceride and plasma medium-chain free fatty acid levels increased less during infusion of the structured triglyceride emulsion than with the physical mixture emulsion. The parenteral structured triglyceride emulsion improves the nitrogen balance and is cleared faster from the blood, compared with the emulsion of the physical mixture of medium- and long-chain triglycerides, in moderately catabolic patients.

Transcriptional analysis of prebiotic uptake and catabolism by Lactobacillus acidophilus NCFM.

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Joakim Mark Andersen

Full Text Available The human gastrointestinal tract can be positively modulated by dietary supplementation of probiotic bacteria in combination with prebiotic carbohydrates. Here differential transcriptomics and functional genomics were used to identify genes in Lactobacillus acidophilus NCFM involved in the uptake and catabolism of 11 potential prebiotic compounds consisting of α- and β-linked galactosides and glucosides. These oligosaccharides induced genes encoding phosphoenolpyruvate-dependent sugar phosphotransferase systems (PTS, galactoside pentose hexuronide (GPH permease, and ATP-binding cassette (ABC transporters. PTS systems were upregulated primarily by di- and tri-saccharides such as cellobiose, isomaltose, isomaltulose, panose and gentiobiose, while ABC transporters were upregulated by raffinose, Polydextrose, and stachyose. A single GPH transporter was induced by lactitol and galactooligosaccharides (GOS. The various transporters were associated with a number of glycoside hydrolases from families 1, 2, 4, 13, 32, 36, 42, and 65, involved in the catabolism of various α- and β-linked glucosides and galactosides. Further subfamily specialization was also observed for different PTS-associated GH1 6-phospho-β-glucosidases implicated in the catabolism of gentiobiose and cellobiose. These findings highlight the broad oligosaccharide metabolic repertoire of L. acidophilus NCFM and establish a platform for selection and screening of both probiotic bacteria and prebiotic compounds that may positively influence the gastrointestinal microbiota.

Genome and Proteome Analysis of Rhodococcus erythropolis MI2: Elucidation of the 4,4´-Dithiodibutyric Acid Catabolism

Science.gov (United States)

Khairy, Heba; Meinert, Christina; Wübbeler, Jan Hendrik; Poehlein, Anja; Daniel, Rolf; Voigt, Birgit; Riedel, Katharina; Steinbüchel, Alexander

2016-01-01

Rhodococcus erythropolis MI2 has the extraordinary ability to utilize the xenobiotic 4,4´-dithiodibutyric acid (DTDB). Cleavage of DTDB by the disulfide-reductase Nox, which is the only verified enzyme involved in DTDB-degradation, raised 4-mercaptobutyric acid (4MB). 4MB could act as building block of a novel polythioester with unknown properties. To completely unravel the catabolism of DTDB, the genome of R. erythropolis MI2 was sequenced, and subsequently the proteome was analyzed. The draft genome sequence consists of approximately 7.2 Mbp with an overall G+C content of 62.25% and 6,859 predicted protein-encoding genes. The genome of strain MI2 is composed of three replicons: one chromosome and two megaplasmids with sizes of 6.45, 0.4 and 0.35 Mbp, respectively. When cells of strain MI2 were cultivated with DTDB as sole carbon source and compared to cells grown with succinate, several interesting proteins with significantly higher expression levels were identified using 2D-PAGE and MALDI-TOF mass spectrometry. A putative luciferase-like monooxygenase-class F420-dependent oxidoreductase (RERY_05640), which is encoded by one of the 126 monooxygenase-encoding genes of the MI2-genome, showed a 3-fold increased expression level. This monooxygenase could oxidize the intermediate 4MB into 4-oxo-4-sulfanylbutyric acid. Next, a desulfurization step, which forms succinic acid and volatile hydrogen sulfide, is proposed. One gene coding for a putative desulfhydrase (RERY_06500) was identified in the genome of strain MI2. However, the gene product was not recognized in the proteome analyses. But, a significant expression level with a ratio of up to 7.3 was determined for a putative sulfide:quinone oxidoreductase (RERY_02710), which could also be involved in the abstraction of the sulfur group. As response to the toxicity of the intermediates, several stress response proteins were strongly expressed, including a superoxide dismutase (RERY_05600) and an osmotically induced

Genome and Proteome Analysis of Rhodococcus erythropolis MI2: Elucidation of the 4,4´-Dithiodibutyric Acid Catabolism.

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Heba Khairy

Full Text Available Rhodococcus erythropolis MI2 has the extraordinary ability to utilize the xenobiotic 4,4´-dithiodibutyric acid (DTDB. Cleavage of DTDB by the disulfide-reductase Nox, which is the only verified enzyme involved in DTDB-degradation, raised 4-mercaptobutyric acid (4MB. 4MB could act as building block of a novel polythioester with unknown properties. To completely unravel the catabolism of DTDB, the genome of R. erythropolis MI2 was sequenced, and subsequently the proteome was analyzed. The draft genome sequence consists of approximately 7.2 Mbp with an overall G+C content of 62.25% and 6,859 predicted protein-encoding genes. The genome of strain MI2 is composed of three replicons: one chromosome and two megaplasmids with sizes of 6.45, 0.4 and 0.35 Mbp, respectively. When cells of strain MI2 were cultivated with DTDB as sole carbon source and compared to cells grown with succinate, several interesting proteins with significantly higher expression levels were identified using 2D-PAGE and MALDI-TOF mass spectrometry. A putative luciferase-like monooxygenase-class F420-dependent oxidoreductase (RERY_05640, which is encoded by one of the 126 monooxygenase-encoding genes of the MI2-genome, showed a 3-fold increased expression level. This monooxygenase could oxidize the intermediate 4MB into 4-oxo-4-sulfanylbutyric acid. Next, a desulfurization step, which forms succinic acid and volatile hydrogen sulfide, is proposed. One gene coding for a putative desulfhydrase (RERY_06500 was identified in the genome of strain MI2. However, the gene product was not recognized in the proteome analyses. But, a significant expression level with a ratio of up to 7.3 was determined for a putative sulfide:quinone oxidoreductase (RERY_02710, which could also be involved in the abstraction of the sulfur group. As response to the toxicity of the intermediates, several stress response proteins were strongly expressed, including a superoxide dismutase (RERY_05600 and an

Construction and Optimization of a Heterologous Pathway for Protocatechuate Catabolism in Escherichia coli Enables Bioconversion of Model Aromatic Compounds.

Science.gov (United States)

Clarkson, Sonya M; Giannone, Richard J; Kridelbaugh, Donna M; Elkins, James G; Guss, Adam M; Michener, Joshua K

2017-09-15

The production of biofuels from lignocellulose yields a substantial lignin by-product stream that currently has few applications. Biological conversion of lignin-derived compounds into chemicals and fuels has the potential to improve the economics of lignocellulose-derived biofuels, but few microbes are able both to catabolize lignin-derived aromatic compounds and to generate valuable products. While Escherichia coli has been engineered to produce a variety of fuels and chemicals, it is incapable of catabolizing most aromatic compounds. Therefore, we engineered E. coli to catabolize protocatechuate, a common intermediate in lignin degradation, as the sole source of carbon and energy via heterologous expression of a nine-gene pathway from Pseudomonas putida KT2440. We next used experimental evolution to select for mutations that increased growth with protocatechuate more than 2-fold. Increasing the strength of a single ribosome binding site in the heterologous pathway was sufficient to recapitulate the increased growth. After optimization of the core pathway, we extended the pathway to enable catabolism of a second model compound, 4-hydroxybenzoate. These engineered strains will be useful platforms to discover, characterize, and optimize pathways for conversions of lignin-derived aromatics. IMPORTANCE Lignin is a challenging substrate for microbial catabolism due to its polymeric and heterogeneous chemical structure. Therefore, engineering microbes for improved catabolism of lignin-derived aromatic compounds will require the assembly of an entire network of catabolic reactions, including pathways from genetically intractable strains. Constructing defined pathways for aromatic compound degradation in a model host would allow rapid identification, characterization, and optimization of novel pathways. We constructed and optimized one such pathway in E. coli to enable catabolism of a model aromatic compound, protocatechuate, and then extended the pathway to a related

Utilization of alimentary protein and amino acids in satisfying the nitrogen requirements of monogastric mammals

International Nuclear Information System (INIS)

Pion, R.; Arnal, M.

1976-01-01

The nitrogenous matter in the food of monogastric animals consists mainly of proteins, which are rapidly hydrolized in the intestinal tract when they have left the gastric reservoir. The digestive tube has several roles: it provides for hydrolysis of the food proteins and for a supply of endogenous nitrogen; it enables a certain digestive function to be performed by the intestinal flora and permits the transport of amino acids into the blood, selecting those which are needed for protein synthesis. The digestion products appear mainly in the form of free amino acids in the portal blood. A large proportion of these amino acids is taken up by the liver, so that intense protein synthesis takes place in the latter, coupled with a decrease in catabolism leading to a rhythmic increase in the liver content of proteins and RNA. The labile proteins retained are mainly enzymes, which catabolize the amino acids, and the liver is the site of the catabolism of most of the excess amino acids except those with chain branching. Alimentary deficiencies do not markedly reduce protein synthesis in this organ, since the rate of re-utilization of the amino acids is increased and the liver thus plays a regulatory role. The utilization of amino acids in muscle also follows a certain rhythm, partly connected with feeding, and under hormonal control. The muscle is the seat of catabolism of a large part of the branched chain amino acids, and like the liver it contributes to the energy utilization of amino acids. The rate of utilization of certain essential amino acids can be measured by metabolic criteria, including determination of blood and muscle concentrations and excretion of 14 CO 2 labels in the exhaled air or of 35 S labels in urine. (author)

NormaCurve: a SuperCurve-based method that simultaneously quantifies and normalizes reverse phase protein array data.

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Sylvie Troncale

Full Text Available MOTIVATION: Reverse phase protein array (RPPA is a powerful dot-blot technology that allows studying protein expression levels as well as post-translational modifications in a large number of samples simultaneously. Yet, correct interpretation of RPPA data has remained a major challenge for its broad-scale application and its translation into clinical research. Satisfying quantification tools are available to assess a relative protein expression level from a serial dilution curve. However, appropriate tools allowing the normalization of the data for external sources of variation are currently missing. RESULTS: Here we propose a new method, called NormaCurve, that allows simultaneous quantification and normalization of RPPA data. For this, we modified the quantification method SuperCurve in order to include normalization for (i background fluorescence, (ii variation in the total amount of spotted protein and (iii spatial bias on the arrays. Using a spike-in design with a purified protein, we test the capacity of different models to properly estimate normalized relative expression levels. The best performing model, NormaCurve, takes into account a negative control array without primary antibody, an array stained with a total protein stain and spatial covariates. We show that this normalization is reproducible and we discuss the number of serial dilutions and the number of replicates that are required to obtain robust data. We thus provide a ready-to-use method for reliable and reproducible normalization of RPPA data, which should facilitate the interpretation and the development of this promising technology. AVAILABILITY: The raw data, the scripts and the normacurve package are available at the following web site: http://microarrays.curie.fr.

Overproduction of a kinetic subclass of VLDL-apoB, and direct catabolism of VLDL-apoB in human endogenous hypertriglyceridemia: an analytical model solution of tracer data

International Nuclear Information System (INIS)

Eaton, R.P.; Allen, R.C.; Schade, D.S.

1983-01-01

To investigate the participation of the major apoprotein involved in triglyceride transport in the pathogenesis of endogenous hypertriglyceridemia, five kinetic studies of apoprotein B were conducted in volunteer normolipidemic subjects and six studies in four patients with endogenous hypertriglyceridemia. The transport of apoprotein B within four kinetic subclasses of very low density lipoprotein (VLDL), intermediate density lipoprotein (IDL), and low density lipoprotein (LDL) was studied by injection of [ 75 Se]selenomethionine. A 24-fold increase in the entry of newly synthesized apoprotein B at the initial kinetic subclass of the four-compartment VLDL delipidation sequence characterized the hypertriglyceridemic studies relative to normal subjects. Moreover, approximately 75 mg/kg per day of VLDL-B turnover reflected direct catabolism independent of conversion to IDL and/or to LDL, in contrast to the 8 mg/kg per day observed in controls. IDL-B was derived from VLDL-B in both normal and hypertriglyceridemic subjects, and was responsible for greater than 70% of all LDL-B synthesis. LDL-B pool size and turnover were indistinguishable in hypertriglyceridemic subjects from that observed in normal subjects. These studies suggest that two kinetic phenomena may characterize the pathophysiology of endogenous hypertriglyceridemia: a) over-production of apoB within a kinetic subclass of VLDL and b) preferential catabolism of hypertriglyceridemic VLDL without prior conversion to IDL/LDL

Associations of Dietary Protein and Energy Intakes With Protein-Energy Wasting Syndrome in Hemodialysis Patients.

Science.gov (United States)

Beddhu, Srinivasan; Wei, Guo; Chen, Xiaorui; Boucher, Robert; Kiani, Rabia; Raj, Dominic; Chonchol, Michel; Greene, Tom; Murtaugh, Maureen A

2017-09-01

The associations of dietary protein and/or energy intakes with protein or energy wasting in patients on maintenance hemodialysis are controversial. We examined these in the Hemodialysis (HEMO) Study. In 1487 participants in the HEMO Study, baseline dietary protein intake (grams per kilogram per day) and dietary energy intake (kilocalories per kilograms per day) were related to the presence of the protein-energy wasting (PEW) syndrome at month 12 (defined as the presence of at least 1 criteria in 2 of the 3 categories of low serum chemistry, low body mass, and low muscle mass) in logistic regression models. In additional separate models, protein intake estimated from equilibrated normalized protein catabolic rate (enPCR) was also related to the PEW syndrome. Compared with the lowest quartile, the highest quartile of baseline dietary protein intake was paradoxically associated with increased risk of the PEW syndrome at month 12 (odds ratio [OR]: 4.11; 95% confidence interval [CI]: 2.79-6.05). This relationship was completely attenuated (OR: 1.35; 95% CI: 0.88-2.06) with adjustment for baseline body weight, which suggested mathematical coupling. Results were similar for dietary energy intake. Compared with the lowest quartile of baseline enPCR, the highest quartile was not associated with the PEW syndrome at 12 months (OR: 0.78; 95% CI: 0.54-1.12). These data do not support the use of dietary protein intake or dietary energy intake criteria in the definition of the PEW syndrome in patients on maintenance hemodialysis.

Evaluation of cyclooxygenase protein expression in traumatized versus normal tissues from eastern box turtles (Terrapene carolina carolina).

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Royal, Lillian W; Lascelles, B Duncan X; Lewbart, Gregory A; Correa, Maria T; Jones, Samuel L

2012-06-01

This pilot study was designed to determine whether cyclooxygenase (COX)-1, COX-2, or both are expressed in normal turtle tissues and whether level of expression changes when tissue becomes inflamed. Five eastern box turtles, Terrapene carolina carolina, that either died or were euthanatized due to disease or injuries were used for this work. Tissues were obtained from the five turtles. Western blot analysis was used to evaluate tissues for COX-1 and COX-2 proteins. Densiometric analysis was used to compare Western blot bands within each turtle. COX-1 and COX-2 were found in the liver, kidney, grossly normal muscle, and grossly traumatized (inflamed) muscle of all study turtles. In all cases, COX-1 and COX-2 proteins were increased in traumatized muscle over grossly normal nontraumatized muscle. The highest levels of COX-1 and COX-2 proteins were found in kidney and liver. There was no statistical difference between the amount of COX-1 protein in liver and kidney, but traumatized muscle compared with grossly normal muscle had significantly greater COX-1 but not COX 2 protein concentrations. There was no statistical difference between the amount of COX-2 protein in liver and kidney. Traumatized muscle expressed nonstatistically significant greater amounts of COX-2 compared with grossly normal muscle. COX-1 and COX-2 proteins are expressed in turtle tissues, and both isoforms are upregulated during inflammation of muscle tissue. Traditional nonsteroidal anti-inflammatory drugs (NSAIDs) that block both COX isoforms might be more efficacious than COX-2-selective drugs. This work suggests that NSAIDs should be evaluated for potential liver and kidney toxicity in turtles.

Oxygen limitation modulates pH regulation of catabolism and hydrogenases, multidrug transporters, and envelope composition in Escherichia coli K-12

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Radmacher Michael D

2006-10-01

Full Text Available Abstract Background In Escherichia coli, pH regulates genes for amino-acid and sugar catabolism, electron transport, oxidative stress, periplasmic and envelope proteins. Many pH-dependent genes are co-regulated by anaerobiosis, but the overall intersection of pH stress and oxygen limitation has not been investigated. Results The pH dependence of gene expression was analyzed in oxygen-limited cultures of E. coli K-12 strain W3110. E. coli K-12 strain W3110 was cultured in closed tubes containing LBK broth buffered at pH 5.7, pH 7.0, and pH 8.5. Affymetrix array hybridization revealed pH-dependent expression of 1,384 genes and 610 intergenic regions. A core group of 251 genes showed pH responses similar to those in a previous study of cultures grown with aeration. The highly acid-induced gene yagU was shown to be required for extreme-acid resistance (survival at pH 2. Acid also up-regulated fimbriae (fimAC, periplasmic chaperones (hdeAB, cyclopropane fatty acid synthase (cfa, and the "constitutive" Na+/H+ antiporter (nhaB. Base up-regulated core genes for maltodextrin transport (lamB, mal, ATP synthase (atp, and DNA repair (recA, mutL. Other genes showed opposite pH responses with or without aeration, for example ETS components (cyo,nuo, sdh and hydrogenases (hya, hyb, hyc, hyf, hyp. A hypF strain lacking all hydrogenase activity showed loss of extreme-acid resistance. Under oxygen limitation only, acid down-regulated ribosome synthesis (rpl,rpm, rps. Acid up-regulated the catabolism of sugar derivatives whose fermentation minimized acid production (gnd, gnt, srl, and also a cluster of 13 genes in the gadA region. Acid up-regulated drug transporters (mdtEF, mdtL, but down-regulated penicillin-binding proteins (dacACD, mreBC. Intergenic regions containing regulatory sRNAs were up-regulated by acid (ryeA, csrB, gadY, rybC. Conclusion pH regulates a core set of genes independently of oxygen, including yagU, fimbriae, periplasmic chaperones, and nha

Detection and isolation of novel rhizopine-catabolizing bacteria from the environment

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Gardener; de Bruijn FJ

1998-12-01

Microbial rhizopine-catabolizing (Moc) activity was detected in serial dilutions of soil and rhizosphere washes. The activity observed generally ranged between 10(6) and 10(7) catabolic units per g, and the numbers of nonspecific culture-forming units were found to be approximately 10 times higher. A diverse set of 37 isolates was obtained by enrichment on scyllo-inosamine-containing media. However, none of the bacteria that were isolated were found to contain DNA sequences homologous to the known mocA, mocB, and mocC genes of Sinorhizobium meliloti L5-30. Twenty-one of the isolates could utilize an SI preparation as the sole carbon and nitrogen source for growth. Partial sequencing of 16S ribosomal DNAs (rDNAs) amplified from these strains indicated that five distinct bacterial genera (Arthrobacter, Sinorhizobium, Pseudomonas, Aeromonas, and Alcaligenes) were represented in this set. Only 6 of these 21 isolates could catabolize 3-O-methyl-scyllo-inosamine under standard assay conditions. Two of these, strains D1 and R3, were found to have 16S rDNA sequences very similar to those of Sinorhizobium meliloti. However, these strains are not symbiotically effective on Medicago sativa, and DNA sequences homologous to the nodB and nodC genes were not detected in strains D1 and R3 by Southern hybridization analysis.

Draft Genome Sequences of Three β-Lactam-Catabolizing Soil Proteobacteria

DEFF Research Database (Denmark)

Crofts, Terence S.; Wang, Bin; Spivak, Aaron

2017-01-01

Most antibiotics are derived from the soil, but their catabolism there, which is necessary to close the antibiotic carbon cycle, remains uncharacterized. We report the first draft genome sequences of soil Proteobacteria identified for subsisting solely on β-lactams as their carbon sources...

Defective branched chain amino acid catabolism contributes to cardiac dysfunction and remodeling following myocardial infarction.

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Wang, Wei; Zhang, Fuyang; Xia, Yunlong; Zhao, Shihao; Yan, Wenjun; Wang, Helin; Lee, Yan; Li, Congye; Zhang, Ling; Lian, Kun; Gao, Erhe; Cheng, Hexiang; Tao, Ling

2016-11-01

Cardiac metabolic remodeling is a central event during heart failure (HF) development following myocardial infarction (MI). It is well known that myocardial glucose and fatty acid dysmetabolism contribute to post-MI cardiac dysfunction and remodeling. However, the role of amino acid metabolism in post-MI HF remains elusive. Branched chain amino acids (BCAAs) are an important group of essential amino acids and function as crucial nutrient signaling in mammalian animals. The present study aimed to determine the role of cardiac BCAA metabolism in post-MI HF progression. Utilizing coronary artery ligation-induced murine MI models, we found that myocardial BCAA catabolism was significantly impaired in response to permanent MI, therefore leading to an obvious elevation of myocardial BCAA abundance. In MI-operated mice, oral BCAA administration further increased cardiac BCAA levels, activated the mammalian target of rapamycin (mTOR) signaling, and exacerbated cardiac dysfunction and remodeling. These data demonstrate that BCAAs act as a direct contributor to post-MI cardiac pathologies. Furthermore, these BCAA-mediated deleterious effects were improved by rapamycin cotreatment, revealing an indispensable role of mTOR in BCAA-mediated adverse effects on cardiac function/structure post-MI. Of note, pharmacological inhibition of branched chain ketoacid dehydrogenase kinase (BDK), a negative regulator of myocardial BCAA catabolism, significantly improved cardiac BCAA catabolic disorders, reduced myocardial BCAA levels, and ameliorated post-MI cardiac dysfunction and remodeling. In conclusion, our data provide the evidence that impaired cardiac BCAA catabolism directly contributes to post-MI cardiac dysfunction and remodeling. Moreover, improving cardiac BCAA catabolic defects may be a promising therapeutic strategy against post-MI HF. Copyright © 2016 the American Physiological Society.

Anaerobic catabolism of aromatic compounds: a genetic and genomic view.

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Carmona, Manuel; Zamarro, María Teresa; Blázquez, Blas; Durante-Rodríguez, Gonzalo; Juárez, Javier F; Valderrama, J Andrés; Barragán, María J L; García, José Luis; Díaz, Eduardo

2009-03-01

Aromatic compounds belong to one of the most widely distributed classes of organic compounds in nature, and a significant number of xenobiotics belong to this family of compounds. Since many habitats containing large amounts of aromatic compounds are often anoxic, the anaerobic catabolism of aromatic compounds by microorganisms becomes crucial in biogeochemical cycles and in the sustainable development of the biosphere. The mineralization of aromatic compounds by facultative or obligate anaerobic bacteria can be coupled to anaerobic respiration with a variety of electron acceptors as well as to fermentation and anoxygenic photosynthesis. Since the redox potential of the electron-accepting system dictates the degradative strategy, there is wide biochemical diversity among anaerobic aromatic degraders. However, the genetic determinants of all these processes and the mechanisms involved in their regulation are much less studied. This review focuses on the recent findings that standard molecular biology approaches together with new high-throughput technologies (e.g., genome sequencing, transcriptomics, proteomics, and metagenomics) have provided regarding the genetics, regulation, ecophysiology, and evolution of anaerobic aromatic degradation pathways. These studies revealed that the anaerobic catabolism of aromatic compounds is more diverse and widespread than previously thought, and the complex metabolic and stress programs associated with the use of aromatic compounds under anaerobic conditions are starting to be unraveled. Anaerobic biotransformation processes based on unprecedented enzymes and pathways with novel metabolic capabilities, as well as the design of novel regulatory circuits and catabolic networks of great biotechnological potential in synthetic biology, are now feasible to approach.

Development of phenanthrene catabolism in natural and artificial soils

International Nuclear Information System (INIS)

Rhodes, Angela H.; Hofman, Jakub; Semple, Kirk T.

2008-01-01

The characteristics of natural soils often vary from those of artificial soil (e.g. OECD), which may lead to substantial differences in the bioavailability of test substances. The aim of this investigation was to characterise the development of phenanthrene catabolism in both natural and artificial soils with varying total organic carbon (TOC) content after 1, 14, 42 and 84 d soil-phenanthrene contact time. Indigenous catabolic activity was measured via the addition of 14 C-phenanthrene using the respirometric soil slurry assay. Notably, the lag phases, fastest rates and total extents of 14 C-phenanthrene degradation were relatively comparable in soils with similar TOC content after 1 d contact time. However, natural soils generally exhibited significantly shorter lag phases, faster rates and higher extents of mineralisation, than their artificial counterparts after 42 and 84 d contact time. Such findings suggest that the extrapolation of results from artificial soils to real/natural soils may not be straightforward. - Natural and artificial soils display different phenanthrene mineralisation profiles suggesting that the extrapolation of results from artificial soils to real/natural soils may not be straightforward

Impact of protein uptake and degradation on recombinant protein secretion in yeast

DEFF Research Database (Denmark)

Tyo, Keith E. J.; Liu, Zihe; Magnusson, Ylva

2014-01-01

Protein titers, a key bioprocessing metric, depend both on the synthesis of protein and the degradation of protein. Secreted recombinant protein production in Saccharomyces cerevisiae is an attractive platform as minimal media can be used for cultivation, thus reducing fermentation costs...... and transcriptomics, we identify metabolic and regulatory markers that are consistent with uptake of whole proteins by endocytosis, followed by intracellular degradation and catabolism of substituent amino acids. Uptake and degradation of recombinant protein products may be common in S. cerevisiae protein secretion...... and simplifying downstream purification, compared to other systems that require complex media. As such, engineering S. cerevisiae to improve titers has been then the subject of significant attention, but the majority of previous efforts have been focused on improving protein synthesis. Here, we characterize...

A transthyretin-related protein is functionally expressed in Herbaspirillum seropedicae.

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Matiollo, Camila; Vernal, Javier; Ecco, Gabriela; Bertoldo, Jean Borges; Razzera, Guilherme; de Souza, Emanuel M; Pedrosa, Fábio O; Terenzi, Hernán

2009-10-02

Transthyretin-related proteins (TRPs) constitute a family of proteins structurally related to transthyretin (TTR) and are found in a large range of bacterial, fungal, plant, invertebrate, and vertebrate species. However, it was recently recognized that both prokaryotic and eukaryotic members of this family are not functionally related to transthyretins. TRPs are in fact involved in the purine catabolic pathway and function as hydroxyisourate hydrolases. An open reading frame encoding a protein similar to the Escherichia coli TRP was identified in Herbaspirillum seropedicae genome (Hs_TRP). It was cloned, overexpressed in E. coli, and purified to homogeneity. Mass spectrometry data confirmed the identity of this protein, and circular dichroism spectrum indicated a predominance of beta-sheet structure, as expected for a TRP. We have demonstrated that Hs_TRP is a 5-hydroxyisourate hydrolase and by site-directed mutagenesis the importance of three conserved catalytic residues for Hs_TRP activity was further confirmed. The production of large quantities of this recombinant protein opens up the possibility of obtaining its 3D-structure and will help further investigations into purine catabolism.

Bactericidal peptidoglycan recognition protein induces oxidative stress in Escherichia coli through a block in respiratory chain and increase in central carbon catabolism.

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Kashyap, Des R; Kuzma, Marcin; Kowalczyk, Dominik A; Gupta, Dipika; Dziarski, Roman

2017-09-01

Mammalian Peptidoglycan Recognition Proteins (PGRPs) kill both Gram-positive and Gram-negative bacteria through simultaneous induction of oxidative, thiol and metal stress responses in bacteria. However, metabolic pathways through which PGRPs induce these bactericidal stress responses are unknown. We screened Keio collection of Escherichia coli deletion mutants and revealed that deleting genes for respiratory chain flavoproteins or for tricarboxylic acid (TCA) cycle resulted in increased resistance of E. coli to PGRP killing. PGRP-induced killing depended on the production of hydrogen peroxide, which required increased supply of NADH for respiratory chain oxidoreductases from central carbon catabolism (glycolysis and TCA cycle), and was controlled by cAMP-Crp. Bactericidal PGRP induced a rapid decrease in respiration, which suggested that the main source of increased production of hydrogen peroxide was a block in respiratory chain and diversion of electrons from NADH oxidoreductases to oxygen. CpxRA two-component system was a negative regulator of PGRP-induced oxidative stress. By contrast, PGRP-induced thiol stress (depletion of thiols) and metal stress (increase in intracellular free Zn 2+ through influx of extracellular Zn 2+ ) were mostly independent of oxidative stress. Thus, manipulating pathways that induce oxidative, thiol and metal stress in bacteria could be a useful strategy to design new approaches to antibacterial therapy. © 2017 John Wiley & Sons Ltd.

Expression of Bcl-2 family proteins and spontaneous apoptosis in normal human testis.

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Oldereid, N B; Angelis, P D; Wiger, R; Clausen, O P

2001-05-01

We investigated the frequency of spontaneous apoptosis and expression of the Bcl-2 family of proteins during normal spermatogenesis in man. Testicular tissue with both normal morphology and DNA content was obtained from necro-donors and fixed in Bouin's solution. A TdT-mediated dUTP end-labelling method (TUNEL) was used for the detection of apoptotic cells. Expression of apoptosis regulatory Bcl-2 family proteins and of p53 and p21(Waf1) was assessed by immunohistochemistry. Germ cell apoptosis was detected in all testes and was mainly seen in primary spermatocytes and spermatids and in a few spermatogonia. Bcl-2 and Bak were preferentially expressed in the compartments of spermatocytes and differentiating spermatids, while Bcl-x was preferentially expressed in spermatogonia. Bax showed a preferential expression in nuclei of round spermatids, whereas Bad was only seen in the acrosome region of various stages of spermatids. Mcl-1 staining was weak without a particular pattern, whereas expression of Bcl-w, p53 and p21(Waf1) proteins was not detected by immunohistochemistry. The results show that spontaneous apoptosis occurs in all male germ cell compartments in humans. Bcl-2 family proteins are distributed preferentially within distinct germ cell compartments suggesting a specific role for these proteins in the processes of differentiation and maturation during human spermatogenesis.

Plant-bacteria partnership: phytoremediation of hydrocarbons contaminated soil and expression of catabolic genes

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Hamna Saleem

2016-01-01

Full Text Available Petroleum hydrocarbons are harmful to living organisms when they are exposed in natural environment. Once they come in contact, it is not an easy to remove them because many of their constituents are persistent in nature. To achieve this target, different approaches have been exploited by using plants, bacteria, and plant-bacteria together. Among them, combined use of plants and bacteria has gained tremendous attention as bacteria possess set of catabolic genes which produce catabolic enzymes to decontaminate hydrocarbons. In return, plant ooze out root exudates containing nutrients and necessary metabolites which facilitate the microbial colonization in plant rhizosphere. This results into high gene abundance and gene expression in the rhizosphere and, thus, leads to enhanced degradation. Moreover, high proportions of beneficial bacteria helps plant to gain more biomass due to their plant growth promoting activities and production of phytohromones. This review focuses functioning and mechanisms of catabolic genes responsible for degradation of straight chain and aromatic hydrocarbons with their potential of degradation in bioremediation. With the understanding of expression mechanisms, rate of degradation can be enhanced by adjusting environmental factors and acclimatizing plant associated bacteria in plant rhizosphere.

On the variability of the salting-out curves of proteins of normal human plasma and serum

NARCIS (Netherlands)

Steyn-Parvé, Elizabeth P.; Hout, A.J. van den

1953-01-01

Salting-out curves of proteins of normal human plasma reflect the influence of a number of other factors besides the protein composition: the manner of obtaining the blood, the nature of the anti-coagulant used, the non-protein components of the plasma. Diagrams of serum and plasma obtained from

Evolutionary Diversification of Alanine Transaminases in Yeast: Catabolic Specialization and Biosynthetic Redundancy

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Ximena Escalera-Fanjul

2017-06-01

Full Text Available Gene duplication is one of the major evolutionary mechanisms providing raw material for the generation of genes with new or modified functions. The yeast Saccharomyces cerevisiae originated after an allopolyploidization event, which involved mating between two different ancestral yeast species. ScALT1 and ScALT2 codify proteins with 65% identity, which were proposed to be paralogous alanine transaminases. Further analysis of their physiological role showed that while ScALT1 encodes an alanine transaminase which constitutes the main pathway for alanine biosynthesis and the sole pathway for alanine catabolism, ScAlt2 does not display alanine transaminase activity and is not involved in alanine metabolism. Moreover, phylogenetic studies have suggested that ScALT1 and ScALT2 come from each one of the two parental strains which gave rise to the ancestral hybrid. The present work has been aimed to the understanding of the properties of the ancestral type Lacchancea kluyveri LkALT1 and Kluyveromyces lactis KlALT1, alanine transaminases in order to better understand the ScALT1 and ScALT2 evolutionary history. These ancestral -type species were chosen since they harbor ALT1 genes, which are related to ScALT2. Presented results show that, although LkALT1 and KlALT1 constitute ScALT1 orthologous genes, encoding alanine transaminases, both yeasts display LkAlt1 and KlAlt1 independent alanine transaminase activity and additional unidentified alanine biosynthetic and catabolic pathway(s. Furthermore, phenotypic analysis of null mutants uncovered the fact that KlAlt1 and LkAlt1 have an additional role, not related to alanine metabolism but is necessary to achieve wild type growth rate. Our study shows that the ancestral alanine transaminase function has been retained by the ScALT1 encoded enzyme, which has specialized its catabolic character, while losing the alanine independent role observed in the ancestral type enzymes. The fact that ScAlt2 conserves 64

Regulation of the rhaEWRBMA Operon Involved in l-Rhamnose Catabolism through Two Transcriptional Factors, RhaR and CcpA, in Bacillus subtilis.

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Hirooka, Kazutake; Kodoi, Yusuke; Satomura, Takenori; Fujita, Yasutaro

2015-12-28

The Bacillus subtilis rhaEWRBMA (formerly yuxG-yulBCDE) operon consists of four genes encoding enzymes for l-rhamnose catabolism and the rhaR gene encoding a DeoR-type transcriptional regulator. DNase I footprinting analysis showed that the RhaR protein specifically binds to the regulatory region upstream of the rhaEW gene, in which two imperfect direct repeats are included. Gel retardation analysis revealed that the direct repeat farther upstream is essential for the high-affinity binding of RhaR and that the DNA binding of RhaR was effectively inhibited by L-rhamnulose-1-phosphate, an intermediate of L-rhamnose catabolism. Moreover, it was demonstrated that the CcpA/P-Ser-HPr complex, primarily governing the carbon catabolite control in B. subtilis, binds to the catabolite-responsive element, which overlaps the RhaR binding site. In vivo analysis of the rhaEW promoter-lacZ fusion in the background of ccpA deletion showed that the L-rhamnose-responsive induction of the rhaEW promoter was negated by the disruption of rhaA or rhaB but not rhaEW or rhaM, whereas rhaR disruption resulted in constitutive rhaEW promoter activity. These in vitro and in vivo results clearly indicate that RhaR represses the operon by binding to the operator site, which is detached by L-rhamnulose-1-phosphate formed from L-rhamnose through a sequence of isomerization by RhaA and phosphorylation by RhaB, leading to the derepression of the operon. In addition, the lacZ reporter analysis using the strains with or without the ccpA deletion under the background of rhaR disruption supported the involvement of CcpA in the carbon catabolite repression of the operon. Since L-rhamnose is a component of various plant-derived compounds, it is a potential carbon source for plant-associating bacteria. Moreover, it is suggested that L-rhamnose catabolism plays a significant role in some bacteria-plant interactions, e.g., invasion of plant pathogens and nodulation of rhizobia. Despite the physiological

Addition of arginine and leucine to low or normal protein diets: performance, carcass characteristics and intramuscular fat of finishing pigs

Energy Technology Data Exchange (ETDEWEB)

Tous, N.; Lizardo, R.; Vilà, B.; Gispert, M.; Font-i-Furnols, M.; Esteve-Garcia, E.

2016-07-01

The effect of dietary crude protein (CP) reduction, supplementation with arginine or leucine on intramuscular fat (IMF) content was evaluated in (Landrace × Duroc) × Pietrain pigs. One-hundred and eight barrows (67 ± 4 kg) were assigned to six diets (n=6 pens of 3 pigs each): four normal CP diets containing 16% CP from 60 to 90 kg and 13% CP from 90 to 115 kg live weight (normal protein; normal protein high Arg, normal protein high Leu or normal protein high Arg and Leu) and two low CP diets containing 14% CP from 60 to 90 kg and 11.8% CP from 90 to 115 kg live weight (with or without supplementation of both amino acids). The high Leu and Arg diets were supplemented to obtain ratios of standard ileal digestible Leu/Lys and Arg/Lys of 4 and 2, respectively. While feed to gain ratio tended to increase (p<0.05), final weight (p<0.01), average daily feed intake (ADFI) (p<0.05) and average daily gain (ADG) (p<0.01) were reduced in animals fed low-protein diets supplemented with Arg and Leu compared to the ones fed low-protein diet unsupplemented. Marbling and IMF content in loin were reduced when Arg was supplemented (p<0.05) in normal protein diets. Supplementing these diets with Arg also reduced belly weight (p<0.01) and increased lean meat percentage (p<0.05). Contrary to the initial hypothesis, reduction of CP or dietary supplementation with Leu had no effect on IMF content and supplementation with Arg reduced it.

Addition of arginine and leucine to low or normal protein diets: performance, carcass characteristics and intramuscular fat of finishing pigs

International Nuclear Information System (INIS)

Tous, N.; Lizardo, R.; Vilà, B.; Gispert, M.; Font-i-Furnols, M.; Esteve-Garcia, E.

2016-01-01

The effect of dietary crude protein (CP) reduction, supplementation with arginine or leucine on intramuscular fat (IMF) content was evaluated in (Landrace × Duroc) × Pietrain pigs. One-hundred and eight barrows (67 ± 4 kg) were assigned to six diets (n=6 pens of 3 pigs each): four normal CP diets containing 16% CP from 60 to 90 kg and 13% CP from 90 to 115 kg live weight (normal protein; normal protein high Arg, normal protein high Leu or normal protein high Arg and Leu) and two low CP diets containing 14% CP from 60 to 90 kg and 11.8% CP from 90 to 115 kg live weight (with or without supplementation of both amino acids). The high Leu and Arg diets were supplemented to obtain ratios of standard ileal digestible Leu/Lys and Arg/Lys of 4 and 2, respectively. While feed to gain ratio tended to increase (p<0.05), final weight (p<0.01), average daily feed intake (ADFI) (p<0.05) and average daily gain (ADG) (p<0.01) were reduced in animals fed low-protein diets supplemented with Arg and Leu compared to the ones fed low-protein diet unsupplemented. Marbling and IMF content in loin were reduced when Arg was supplemented (p<0.05) in normal protein diets. Supplementing these diets with Arg also reduced belly weight (p<0.01) and increased lean meat percentage (p<0.05). Contrary to the initial hypothesis, reduction of CP or dietary supplementation with Leu had no effect on IMF content and supplementation with Arg reduced it.

The Colonic Microbiome and Epithelial Transcriptome Are Altered in Rats Fed a High-Protein Diet Compared with a Normal-Protein Diet.

Science.gov (United States)

Mu, Chunlong; Yang, Yuxiang; Luo, Zhen; Guan, Leluo; Zhu, Weiyun

2016-03-01

A high-protein diet (HPD) can produce hazardous compounds and reduce butyrate-producing bacteria in feces, which may be detrimental to gut health. However, information on whether HPD affects intestinal function is limited. The aim of this study was to determine the impact of an HPD on the microbiota, microbial metabolites, and epithelial transcriptome in the colons of rats. Adult male Wistar rats were fed either a normal-protein diet (20% protein, 56% carbohydrate) or an HPD (45% protein, 30% carbohydrate) for 6 wk (n = 10 rats per group, individually fed). After 6 wk, the colonic microbiome, microbial metabolites, and epithelial transcriptome were determined. Compared with the normal-protein diet, the HPD adversely altered the colonic microbiota by increasing (P 0.7, P < 0.05) with genes and metabolites generally regarded as being involved in disease pathogenesis, suggesting these bacteria may mediate the detrimental effects of HPDs on colonic health. Our findings suggest that the HPD altered the colonic microbial community, shifted the metabolic profile, and affected the host response in the colons of rats toward an increased risk of colonic disease. © 2016 American Society for Nutrition.

Serum and urinary lipoproteins in the human nephrotic syndrome: evidence for renal catabolism of lipoproteins

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Shore, V.G.; Forte, T.; Licht, H.; Lewis, S.B.

1982-03-01

The urinary excretion of lipoproteins and the possibility of catabolic alterations on glomerular filtration were investigated in four nephrotic subjects difering in etiology, serum lipoprotein profile, and 24 hr urinary output of protein and lipids. The apolipoproteins and lipoproteins of urine were compared with those of serum with respect to distribution profile, physical properties, and composition. As expected from molecular sieving effects during glomerular filtration, the urinary HDL were more abundant than the lower density lipoproteins even when the plasma LDL was elevated markedly. Intact apolipoproteins were not found in the concentrated urinary fraction isolated by ultrafiltration between the limits of 10/sup 4/ and 5 x 10/sup 4/ daltons. On the basis of immunoreactivity, gel electrophoresis, and amino acid composition, apolipoproteins B and AI are the major and minor proteins, respectively, of urinary LDL, and apo B is the major protein of the urinary IDL and VLDL. Apolipoproteins AI, AII, CI, CIII, and possibly AIV were isolated from the urinary HDL. As much as 20% of the protein moiety of the urinary HDL appeared to be large apolipoprotien fragments with molecular weights and isoelectric points similar to those of apo CII and apo CIII. The lower density classes of urinary lipoproteins also appeared to have lost apo E and apo C's and to have undergone partial proteolysis.

Construction and Optimization of a Heterologous Pathway for Protocatechuate Catabolism in Escherichia coli Enables Bioconversion of Model Aromatic Compounds

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Clarkson, Sonya M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Biosciences Division; Giannone, Richard J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Chemical Sciences Division; Kridelbaugh, Donna M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Biosciences Division; Elkins, James G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Biosciences Division; Guss, Adam M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Biosciences Division; Michener, Joshua K. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Biosciences Division, BioEnergy Science Center; Vieille, Claire [Michigan State Univ., East Lansing, MI (United States)

2017-07-21

The production of biofuels from lignocellulose yields a substantial lignin by-product stream that currently has few applications. Biological conversion of lignin-derived compounds into chemicals and fuels has the potential to improve the economics of lignocellulose-derived biofuels, but few microbes are able both to catabolize lignin-derived aromatic compounds and to generate valuable products. WhileEscherichia colihas been engineered to produce a variety of fuels and chemicals, it is incapable of catabolizing most aromatic compounds. Therefore, we engineeredE. colito catabolize protocatechuate, a common intermediate in lignin degradation, as the sole source of carbon and energy via heterologous expression of a nine-gene pathway fromPseudomonas putidaKT2440. Then, we used experimental evolution to select for mutations that increased growth with protocatechuate more than 2-fold. Increasing the strength of a single ribosome binding site in the heterologous pathway was sufficient to recapitulate the increased growth. After optimization of the core pathway, we extended the pathway to enable catabolism of a second model compound, 4-hydroxybenzoate. These engineered strains will be useful platforms to discover, characterize, and optimize pathways for conversions of lignin-derived aromatics.

IMPORTANCELignin is a challenging substrate for microbial catabolism due to its polymeric and heterogeneous chemical structure. Therefore, engineering microbes for improved catabolism of lignin-derived aromatic compounds will require the assembly of an entire network of catabolic reactions, including pathways from genetically intractable strains. By constructing defined pathways for aromatic compound degradation in a model host would allow rapid

Serum protein concentration in low-dose total body irradiation of normal and malnourished rats

International Nuclear Information System (INIS)

Viana, W.C.M.; Lambertz, D.; Borges, E.S.; Neto, A.M.O.; Lambertz, K.M.F.T.; Amaral, A.

2016-01-01

Among the radiotherapeutics' modalities, total body irradiation (TBI) is used as treatment for certain hematological, oncological and immunological diseases. The aim of this study was to evaluate the long-term effects of low-dose TBI on plasma concentration of total protein and albumin using prematurely and undernourished rats as animal model. For this, four groups with 9 animals each were formed: Normal nourished (N); Malnourished (M); Irradiated Normal nourished (IN); Irradiated Malnourished (IM). At the age of 28 days, rats of the IN and IM groups underwent total body gamma irradiation with a source of cobalt-60. Total protein and Albumin in the blood serum was quantified by colorimetry. This research indicates that procedures involving low-dose total body irradiation in children have repercussions in the reduction in body-mass as well as in the plasma levels of total protein and albumin. Our findings reinforce the periodic monitoring of total serum protein and albumin levels as an important tool in long-term follow-up of pediatric patients in treatments associated to total body irradiation. - Highlights: • Low-dose total body irradiation (TBI) in children have repercussions in their body-mass. • Long-term total protein and albumin levels are affected by TBI. • The monitoring of total protein and albumin levels are useful in the follow-up of TBI pediatric patients.

Pro-inflammatory stimulation of meniscus cells increases production of matrix metalloproteinases and additional catabolic factors involved in osteoarthritis pathogenesis

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Stone, Austin V.; Loeser, Richard F.; Vanderman, Kadie S.; Long, David L.; Clark, Stephanie C.; Ferguson, Cristin M.

2014-01-01

Objective Meniscus injury increases the risk of osteoarthritis; however, the biologic mechanism remains unknown. We hypothesized that pro-inflammatory stimulation of meniscus would increase production of matrix-degrading enzymes, cytokines and chemokines which cause joint tissue destruction and could contribute to osteoarthritis development. Design Meniscus and cartilage tissue from healthy tissue donors and total knee arthroplasties was cultured. Primary cell cultures were stimulated with pro-inflammatory factors [IL-1β, IL-6, or fibronectin fragments (FnF)] and cellular responses were analyzed by real-time PCR, protein arrays and immunoblots. To determine if NF-κB was required for MMP production, meniscus cultures were treated with inflammatory factors with and without the NF-κB inhibitor, hypoestoxide. Results Normal and osteoarthritic meniscus cells increased their MMP secretion in response to stimulation, but specific patterns emerged that were unique to each stimulus with the greatest number of MMPs expressed in response to FnF. Meniscus collagen and connective tissue growth factor gene expression was reduced. Expression of cytokines (IL-1α, IL-1β, IL-6), chemokines (IL-8, CXCL1, CXCL2, CSF1) and components of the NF-κB and tumor necrosis factor (TNF) family were significantly increased. Cytokine and chemokine protein production was also increased by stimulation. When primary cell cultures were treated with hypoestoxide in conjunction with pro-inflammatory stimulation, p65 activation was reduced as were MMP-1 and MMP-3 production. Conclusions Pro-inflammatory stimulation of meniscus cells increased matrix metalloproteinase production and catabolic gene expression. The meniscus could have an active biologic role in osteoarthritis development following joint injury through increased production of cytokines, chemokines, and matrix-degrading enzymes. PMID:24315792

Addition of arginine and leucine to low or normal protein diets: performance, carcass characteristics and intramuscular fat of finishing pigs

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Núria Tous

2016-12-01

Full Text Available The effect of dietary crude protein (CP reduction, supplementation with arginine or leucine on intramuscular fat (IMF content was evaluated in (Landrace × Duroc × Pietrain pigs. One-hundred and eight barrows (67 ± 4 kg were assigned to six diets (n=6 pens of 3 pigs each: four normal CP diets containing 16% CP from 60 to 90 kg and 13% CP from 90 to 115 kg live weight (normal protein; normal protein high Arg, normal protein high Leu or normal protein high Arg and Leu and two low CP diets containing 14% CP from 60 to 90 kg and 11.8% CP from 90 to 115 kg live weight (with or without supplementation of both amino acids. The high Leu and Arg diets were supplemented to obtain ratios of standard ileal digestible Leu/Lys and Arg/Lys of 4 and 2, respectively. While feed to gain ratio tended to increase (p<0.05, final weight (p<0.01, average daily feed intake (ADFI (p<0.05 and average daily gain (ADG (p<0.01 were reduced in animals fed low-protein diets supplemented with Arg and Leu compared to the ones fed low-protein diet unsupplemented. Marbling and IMF content in loin were reduced when Arg was supplemented (p<0.05 in normal protein diets. Supplementing these diets with Arg also reduced belly weight (p<0.01 and increased lean meat percentage (p<0.05. Contrary to the initial hypothesis, reduction of CP or dietary supplementation with Leu had no effect on IMF content and supplementation with Arg reduced it.

Training reduces catabolic and inflammatory response to a single practice in female volleyball players.

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Eliakim, Alon; Portal, Shawn; Zadik, Zvi; Meckel, Yoav; Nemet, Dan

2013-11-01

We examined the effect of training on hormonal and inflammatory response to a single volleyball practice in elite adolescent players. Thirteen female, national team level, Israeli volleyball players (age 16.0 ± 1.4 years, Tanner stage 4-5) participated in the study. Blood samples were collected before and immediately after a typical 60 minutes of volleyball practice, before and after 7 weeks of training during the initial phase of the season. Training involved tactic and technical drills (20% of time), power and speed drills (25% of time), interval sessions (25% of time), endurance-type training (15% of time), and resistance training (15% of time). To achieve greater training responses, the study was performed during the early phase (first 7 weeks) of the volleyball season. Hormonal measurements included the anabolic hormones growth hormone (GH), insulin-like growth factor-I (IGF-I) and IGF-binding protein-3, the catabolic hormone cortisol, the proinflammatory marker interleukin-6 (IL-6), and the anti-inflammatory marker IL-1 receptor antagonist. Training led to a significant improvement of vertical jump, anaerobic properties (peak and mean power by the Wingate Anaerobic Test), and predicted VO2max (by the 20-m shuttle run). Volleyball practice, both before and after the training intervention, was associated with a significant increase of serum lactate, GH, and IL-6. Training resulted in a significantly reduced cortisol response ([INCREMENT]cortisol: 4.2 ± 13.7 vs. -4.4 ± 12.3 ng · ml, before and after training, respectively; p volleyball practice. The results suggest that along with the improvement of power and anaerobic and aerobic characteristics, training reduces the catabolic and inflammatory response to exercise.

Novel Route for Agmatine Catabolism in Aspergillus niger Involves 4-Guanidinobutyrase.

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Kumar, Sunil; Saragadam, Tejaswani; Punekar, Narayan S

2015-08-15

Agmatine, a significant polyamine in bacteria and plants, mostly arises from the decarboxylation of arginine. The functional importance of agmatine in fungi is poorly understood. The metabolism of agmatine and related guanidinium group-containing compounds in Aspergillus niger was explored through growth, metabolite, and enzyme studies. The fungus was able to metabolize and grow on l-arginine, agmatine, or 4-guanidinobutyrate as the sole nitrogen source. Whereas arginase defined the only route for arginine catabolism, biochemical and bioinformatics approaches suggested the absence of arginine decarboxylase in A. niger. Efficient utilization by the parent strain and also by its arginase knockout implied an arginase-independent catabolic route for agmatine. Urea and 4-guanidinobutyrate were detected in the spent medium during growth on agmatine. The agmatine-grown A. niger mycelia contained significant levels of amine oxidase, 4-guanidinobutyraldehyde dehydrogenase, 4-guanidinobutyrase (GBase), and succinic semialdehyde dehydrogenase, but no agmatinase activity was detected. Taken together, the results support a novel route for agmatine utilization in A. niger. The catabolism of agmatine by way of 4-guanidinobutyrate to 4-aminobutyrate into the Krebs cycle is the first report of such a pathway in any organism. A. niger GBase peptide fragments were identified by tandem mass spectrometry analysis. The corresponding open reading frame from the A. niger NCIM 565 genome was located and cloned. Subsequent expression of GBase in both Escherichia coli and A. niger along with its disruption in A. niger functionally defined the GBase locus (gbu) in the A. niger genome. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Muscle protein analysis. II. Two-dimensional electrophoresis of normal and diseased human skeletal muscle

Energy Technology Data Exchange (ETDEWEB)

Giometti, C.S. (Argonne National Lab., IL); Barany, M.; Danon, M.J.; Anderson, N.G.

1980-07-01

High-resolution two-dimensional electrophoresis was used to analyze the major proteins of normal and pathological human-muscle samples. The normal human-muscle pattern contains four myosin light chains: three that co-migrate with the myosin light chains from rabbit fast muscle (extensor digitorum longus), and one that co-migrates with the light chain 2 from rabbit slow muscle (soleus). Of seven Duchenne muscular dystrophy samples, four yielded patterns with decreased amounts of actin and myosin relative to normal muscle, while three samples gave patterns comparable to that for normal muscle. Six samples from patients with myotonic dystrophy also gave normal patterns. In nemaline rod myopathy, in contrast, the pattern was deficient in two of the fast-type myosin light chains.

Phosphonate biosynthesis and catabolism: a treasure trove of unusual enzymology.

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Peck, Spencer C; van der Donk, Wilfred A

2013-08-01

Natural product biosynthesis has proven a fertile ground for the discovery of novel chemistry. Herein we review the progress made in elucidating the biosynthetic pathways of phosphonate and phosphinate natural products such as the antibacterial compounds dehydrophos and fosfomycin, the herbicidal phosphinothricin-containing peptides, and the antimalarial compound FR-900098. In each case, investigation of the pathway has yielded unusual, and often unprecedented, biochemistry. Likewise, recent investigations have uncovered novel ways to cleave the CP bond to yield phosphate under phosphorus starvation conditions. These include the discovery of novel oxidative cleavage of the CP bond catalyzed by PhnY and PhnZ as well as phosphonohydrolases that liberate phosphate from phosphonoacetate. Perhaps the crown jewel of phosphonate catabolism has been the recent resolution of the longstanding problem of the C-P lyase responsible for reductively cleaving the CP bond of a number of different phosphonates to release phosphate. Taken together, the strides made on both metabolic and catabolic fronts illustrate an array of fascinating biochemistry. Copyright © 2013 Elsevier Ltd. All rights reserved.

Choline Catabolism in Burkholderia thailandensis Is Regulated by Multiple Glutamine Amidotransferase 1-Containing AraC Family Transcriptional Regulators.

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Nock, Adam M; Wargo, Matthew J

2016-09-15

Burkholderia thailandensis is a soil-dwelling bacterium that shares many metabolic pathways with the ecologically similar, but evolutionarily distant, Pseudomonas aeruginosa Among the diverse nutrients it can utilize is choline, metabolizable to the osmoprotectant glycine betaine and subsequently catabolized as a source of carbon and nitrogen, similar to P. aeruginosa Orthologs of genes in the choline catabolic pathway in these two bacteria showed distinct differences in gene arrangement as well as an additional orthologous transcriptional regulator in B. thailandensis In this study, we showed that multiple glutamine amidotransferase 1 (GATase 1)-containing AraC family transcription regulators (GATRs) are involved in regulation of the B. thailandensis choline catabolic pathway (gbdR1, gbdR2, and souR). Using genetic analyses and sequencing the transcriptome in the presence and absence of choline, we identified the likely regulons of gbdR1 (BTH_II1869) and gbdR2 (BTH_II0968). We also identified a functional ortholog for P. aeruginosa souR, a GATR that regulates the metabolism of sarcosine to glycine. GbdR1 is absolutely required for expression of the choline catabolic locus, similar to P. aeruginosa GbdR, while GbdR2 is important to increase expression of the catabolic locus. Additionally, the B. thailandensis SouR ortholog (BTH_II0994) is required for catabolism of choline and its metabolites as carbon sources, whereas in P. aeruginosa, SouR function can by bypassed by GbdR. The strategy employed by B. thailandensis represents a distinct regulatory solution to control choline catabolism and thus provides both an evolutionary counterpoint and an experimental system to analyze the acquisition and regulation of this pathway during environmental growth and infection. Many proteobacteria that occupy similar environmental niches have horizontally acquired orthologous genes for metabolism of compounds useful in their shared environment. The arrangement and differential

mTORC1-independent reduction of retinal protein synthesis in type 1 diabetes.

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Fort, Patrice E; Losiewicz, Mandy K; Pennathur, Subramaniam; Jefferson, Leonard S; Kimball, Scot R; Abcouwer, Steven F; Gardner, Thomas W

2014-09-01

Poorly controlled diabetes has long been known as a catabolic disorder with profound loss of muscle and fat body mass resulting from a simultaneous reduction in protein synthesis and enhanced protein degradation. By contrast, retinal structure is largely maintained during diabetes despite reduced Akt activity and increased rate of cell death. Therefore, we hypothesized that retinal protein turnover is regulated differently than in other insulin-sensitive tissues, such as skeletal muscle. Ins2(Akita) diabetic mice and streptozotocin-induced diabetic rats exhibited marked reductions in retinal protein synthesis matched by a concomitant reduction in retinal protein degradation associated with preserved retinal mass and protein content. The reduction in protein synthesis depended on both hyperglycemia and insulin deficiency, but protein degradation was only reversed by normalization of hyperglycemia. The reduction in protein synthesis was associated with diminished protein translation efficiency but, surprisingly, not with reduced activity of the mTORC1/S6K1/4E-BP1 pathway. Instead, diabetes induced a specific reduction of mTORC2 complex activity. These findings reveal distinctive responses of diabetes-induced retinal protein turnover compared with muscle and liver that may provide a new means to ameliorate diabetic retinopathy. © 2014 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

Physiologically Based Pharmacokinetic Modeling of Therapeutic Proteins.

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Wong, Harvey; Chow, Timothy W

2017-09-01

Biologics or therapeutic proteins are becoming increasingly important as treatments for disease. The most common class of biologics are monoclonal antibodies (mAbs). Recently, there has been an increase in the use of physiologically based pharmacokinetic (PBPK) modeling in the pharmaceutical industry in drug development. We review PBPK models for therapeutic proteins with an emphasis on mAbs. Due to their size and similarity to endogenous antibodies, there are distinct differences between PBPK models for small molecules and mAbs. The high-level organization of a typical mAb PBPK model consists of a whole-body PBPK model with organ compartments interconnected by both blood and lymph flows. The whole-body PBPK model is coupled with tissue-level submodels used to describe key mechanisms governing mAb disposition including tissue efflux via the lymphatic system, elimination by catabolism, protection from catabolism binding to the neonatal Fc (FcRn) receptor, and nonlinear binding to specific pharmacological targets of interest. The use of PBPK modeling in the development of therapeutic proteins is still in its infancy. Further application of PBPK modeling for therapeutic proteins will help to define its developing role in drug discovery and development. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Whole-body protein turnover in malnourished patients with child class B and C cirrhosis on diets low to high in protein energy.

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Dichi, J B; Dichi, I; Maio, R; Correa, C R; Angeleli, A Y; Bicudo, M H; Rezende, T A; Burini, R C

2001-03-01

The purpose of this study was to determine the rate of whole-body protein turnover in moderately and severely alcoholic, malnourished, cirrhotic patients fed with different amounts of protein or energy. Six male patients (Child classes B and C) and four age- and sex-matched healthy control subjects were studied for 18 d in fasting and feeding states; a single oral dose of [(15)N]glycine was used as a tracer and urinary ammonia was the end product. The kinetic study showed that patients had higher protein catabolism while fasting (patients: 3.14 +/- 1.2 g of lean body mass/9 h; controls: 1.8 +/- 0.3 g of lean body mass/9 h; P hyperproteic/hyperenergetic diet when compared with fasting. Nitrogen retention was consistent with the lower protein-catabolism rate; a statistically significant increase in nitrogen balance was observed when patients were fed with the hyperproteic/hyperenergetic diet compared with fasting (4.3 +/- 3.2 g of nitrogen/d and -2.2 +/- 1.9 g of nitrogen/d, respectively; P hyperproteic/hyperenergetic diet is likely needed to improve their clinical and nutritional status.

Investigation of protein and lipid metabolism in thyroid pathology using whole-body radiometry

International Nuclear Information System (INIS)

Gorobets, V.F.; Matveenko, E.G.

1987-01-01

Radiometry of the whole body and its organs was employed to study certain aspects of protein-aminoacid and lipid metabolism in patients with thyroid diseases. Metabolism of human serum 131 I-albumin was studied in 12 patients with neurocirculatory dystonia, in 13 patients with diffuse toxic goiter (in 10 before and after drug therapy) and in 9 controls. 75 Se-methionine aminoacid metabolism was investigated in 9 patients with toxic thyroid adenoma and in 13 controls. The body cell mass was determined in 82 patients with thyrotoxicosis by a measurable amount of 40 K. These data were compared with those of 249 healthy persons. An increase in catabolism of labeled albumin, intensification of labeled methionine metabolism at the tissue level, signs of a decrease in the total amount of metabolic albumin in the body were revealed. Intensification of protein metabolism resulted in a decrease in the body cell mass of these patients. After adequate therapy the above indices of protein metabolism in patients with thyrotoxicosis returned to normal. The assimilation of fatty acids and neutral fat was disturbed both in thyrotoxicosis and hypothyroidism

Urea Recycling Contributes to Nitrogen Retention in Calves Fed Milk Replacer and Low-Protein Solid Feed

NARCIS (Netherlands)

Berends, H.; Borne, van den J.J.G.C.; Røjen, B.A.; Baal, van J.; Gerrits, W.J.J.

2014-01-01

Urea recycling, with urea originating from catabolism of amino acids and hepatic detoxification of ammonia, is particularly relevant for ruminant animals, in which microbial protein contributes substantially to the metabolizable protein supply. However, the quantitative contribution of urea

Omega-oxidation is the major pathway for the catabolism of leukotriene B4 in human polymorphonuclear leukocytes.

Science.gov (United States)

Shak, S; Goldstein, I M

1984-08-25

Leukotriene B4 (LTB4), formed by the 5-lipoxygenase pathway in human polymorphonuclear leukocytes (PMN), may be an important mediator of inflammation. Recent studies suggest that human leukocytes can convert LTB4 to products that are less biologically active. To examine the catabolism of LTB4, we developed (using high performance liquid chromatography) a sensitive, reproducible assay for this mediator and its omega-oxidation products (20-OH- and 20-COOH-LTB4). With this assay, we have found that human PMN (but not human monocytes, lymphocytes, or platelets) convert exogenous LTB4 almost exclusively to 20-OH- and 20-COOH-LTB4 (identified by gas chromatography-mass spectrometry). Catabolism of exogenous LTB4 by omega-oxidation is rapid (t1/2 approximately 4 min at 37 degrees C in reaction mixtures containing 1.0 microM LTB4 and 20 X 10(6) PMN/ml), temperature-dependent (negligible at 0 degrees C), and varies with cell number as well as with initial substrate concentration. The pathway for omega-oxidation in PMN is specific for LTB4 and 5(S),12(S)-dihydroxy-6,8,10,14-eicosatetraenoic acid (only small amounts of other dihydroxylated-derivatives of arachidonic acid are converted to omega-oxidation products). Even PMN that are stimulated by phorbol myristate acetate to produce large amounts of superoxide anion radicals catabolize exogenous leukotriene B4 primarily by omega-oxidation. Finally, LTB4 that is generated when PMN are stimulated with the calcium ionophore, A23187, is rapidly catabolized by omega-oxidation. Thus, human PMN not only generate and respond to LTB4, but also rapidly and specifically catabolize this mediator by omega-oxidation.

The role of polyamine catabolism in anti-tumour drug response.

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Casero, R A; Wang, Y; Stewart, T M; Devereux, W; Hacker, A; Wang, Y; Smith, R; Woster, P M

2003-04-01

Interest in polyamine catabolism has increased since it has been directly associated with the cytotoxic response of multiple tumour types to exposure to specific anti-tumour polyamine analogues. Human polyamine catabolism was considered to be a two-step pathway regulated by the rate-limiting enzyme spermidine/spermine N(1)-acetyltransferase (SSAT) that provides substrate for an acetylpolyamine oxidase (APAO). Further, the super-induction of SSAT by several anti-tumour polyamine analogues has been implicated in the cytotoxic response of specific solid-tumour phenotypes to these agents. This high induction of SSAT has been correlated with cellular response to the anti-tumour polyamine analogues in several systems and considerable progress has been made in understanding the molecular mechanisms that regulate the analogue-induced expression of SSAT. A polyamine response element has been identified and the transacting transcription factors that bind and stimulate transcription of SSAT have been cloned and characterized. The link between SSAT activity and cellular toxicity is thought to be based on the production of H(2)O(2) by the activity of the constitutive APAO that uses the SSAT-produced acetylated polyamines. The high induction of SSAT and the subsequent activity of APAO are linked to the cytotoxic response of some tumour cell types to specific polyamine analogues. However, we have recently cloned a variably spliced human polyamine oxidase (PAOh1) that is inducible by specific polyamine analogues, efficiently uses unacetylated spermine as a substrate, and also produces toxic H(2)O(2) as a product. The results of studies with PAOh1 suggest that it is an additional enzyme in polyamine catabolism that has the potential to significantly contribute to polyamine homoeostasis and drug response. Most importantly, PAOh1 is induced by specific polyamine analogues in a tumour-phenotype-specific manner in cell lines representative of the major forms of solid tumours, including

Collagen turnover in normal and degenerate human intervertebral discs as determined by the racemization of aspartic acid

NARCIS (Netherlands)

Sivan, S.-S.; Wachtel, E.; Tsitron, E.; Sakkee, N.; Ham, F. van der; Groot, J.de; Roberts, S.; Maroudas, A.

2008-01-01

Knowledge of rates of protein turnover is important for a quantitative understanding of tissue synthesis and catabolism. In this work, we have used the racemization of aspartic acid as a marker for the turnover of collagen obtained from healthy and pathological human intervertebral disc matrices. We

Normal mode analysis as a method to derive protein dynamics information from the Protein Data Bank.

Science.gov (United States)

Wako, Hiroshi; Endo, Shigeru

2017-12-01

Normal mode analysis (NMA) can facilitate quick and systematic investigation of protein dynamics using data from the Protein Data Bank (PDB). We developed an elastic network model-based NMA program using dihedral angles as independent variables. Compared to the NMA programs that use Cartesian coordinates as independent variables, key attributes of the proposed program are as follows: (1) chain connectivity related to the folding pattern of a polypeptide chain is naturally embedded in the model; (2) the full-atom system is acceptable, and owing to a considerably smaller number of independent variables, the PDB data can be used without further manipulation; (3) the number of variables can be easily reduced by some of the rotatable dihedral angles; (4) the PDB data for any molecule besides proteins can be considered without coarse-graining; and (5) individual motions of constituent subunits and ligand molecules can be easily decomposed into external and internal motions to examine their mutual and intrinsic motions. Its performance is illustrated with an example of a DNA-binding allosteric protein, a catabolite activator protein. In particular, the focus is on the conformational change upon cAMP and DNA binding, and on the communication between their binding sites remotely located from each other. In this illustration, NMA creates a vivid picture of the protein dynamics at various levels of the structures, i.e., atoms, residues, secondary structures, domains, subunits, and the complete system, including DNA and cAMP. Comparative studies of the specific protein in different states, e.g., apo- and holo-conformations, and free and complexed configurations, provide useful information for studying structurally and functionally important aspects of the protein.

The effect of ketoconazole on post-burn inflammation, hypermetabolism and clinical outcomes.

Directory of Open Access Journals (Sweden)

Marc G Jeschke

Full Text Available BACKGROUND: Hypercortisolemia has been suggested as a primary hormonal mediator of whole-body catabolism following severe burn injury. Ketoconazole, an anti-fungal agent, inhibits cortisol synthesis. We, therefore, studied the effect of ketoconazole on post-burn cortisol levels and the hyper-catabolic response in a prospective randomized trial (block randomization 2:1. METHODOLOGY/PRINCIPAL FINDINGS: Fifty-five severely burned pediatric patients with >30% total body surface area (TBSA burns were enrolled in this trial. Patients were randomized to receive standard care plus either placebo (controls, n = 38 or ketoconazole (n = 23. Demographics, clinical data, serum hormone levels, serum cytokine expression profiles, organ function, hypermetabolism measures, muscle protein synthesis, incidence of wound infection sepsis, and body composition were obtained throughout the acute hospital course. Statistical analysis was performed using Fisher's exact test, Student's t-test, and parametric and non-parametric two-way repeated measures analysis of variance where applicable. Patients were similar in demographics, age, and TBSA burned. Ketoconazole effectively blocked cortisol production, as indicated by normalization of the 8-fold elevation in urine cortisol levels [F(1, 376 = 85.34, p<.001] with the initiation of treatment. However, there were no significant differences in the inflammatory response, acute-phase proteins, body composition, muscle protein breakdown or synthesis, or organ function between groups. CONCLUSIONS: Both groups were markedly hypermetabolic and catabolic throughout the acute hospital stay. Normalization of hypercortisolemia with ketoconazole therapy had no effect on whole-body catabolism or the post-burn inflammatory or hypermetabolic response, suggesting that hypercortisolemia does not play a central role in the post-burn hypermetabolic catabolic response. TRIAL REGISTRATION: ClinicalTrials.gov NCT00675714; and NCT

Whey protein supplementation does not alter plasma branched-chained amino acid profiles but results in unique metabolomics patterns in obese women enrolled in an 8-week weight loss trial

Science.gov (United States)

Background: It has been suggested that perturbations in branched-chain amino acid (BCAA) catabolism are associated with insulin resistance and contribute to elevated systemic BCAAs. Evidence in rodents suggests dietary protein rich in BCAAs can increase BCAA catabolism, but there is limited evidence...

Acid Evolution of Escherichia coli K-12 Eliminates Amino Acid Decarboxylases and Reregulates Catabolism.

Science.gov (United States)

He, Amanda; Penix, Stephanie R; Basting, Preston J; Griffith, Jessie M; Creamer, Kaitlin E; Camperchioli, Dominic; Clark, Michelle W; Gonzales, Alexandra S; Chávez Erazo, Jorge Sebastian; George, Nadja S; Bhagwat, Arvind A; Slonczewski, Joan L

2017-06-15

Acid-adapted strains of Escherichia coli K-12 W3110 were obtained by serial culture in medium buffered at pH 4.6 (M. M. Harden, A. He, K. Creamer, M. W. Clark, I. Hamdallah, K. A. Martinez, R. L. Kresslein, S. P. Bush, and J. L. Slonczewski, Appl Environ Microbiol 81:1932-1941, 2015, https://doi.org/10.1128/AEM.03494-14). Revised genomic analysis of these strains revealed insertion sequence (IS)-driven insertions and deletions that knocked out regulators CadC (acid induction of lysine decarboxylase), GadX (acid induction of glutamate decarboxylase), and FNR (anaerobic regulator). Each acid-evolved strain showed loss of one or more amino acid decarboxylase systems, which normally help neutralize external acid (pH 5 to 6) and increase survival in extreme acid (pH 2). Strains from populations B11, H9, and F11 had an IS 5 insertion or IS-mediated deletion in cadC , while population B11 had a point mutation affecting the arginine activator adiY The cadC and adiY mutants failed to neutralize acid in the presence of exogenous lysine or arginine. In strain B11-1, reversion of an rpoC (RNA polymerase) mutation partly restored arginine-dependent neutralization. All eight strains showed deletion or downregulation of the Gad acid fitness island. Strains with the Gad deletion lost the ability to produce GABA (gamma-aminobutyric acid) and failed to survive extreme acid. Transcriptome sequencing (RNA-seq) of strain B11-1 showed upregulated genes for catabolism of diverse substrates but downregulated acid stress genes (the biofilm regulator ariR , yhiM , and Gad). Other strains showed downregulation of H 2 consumption mediated by hydrogenases ( hya and hyb ) which release acid. Strains F9-2 and F9-3 had a deletion of fnr and showed downregulation of FNR-dependent genes ( dmsABC , frdABCD , hybABO , nikABCDE , and nrfAC ). Overall, strains that had evolved in buffered acid showed loss or downregulation of systems that neutralize unbuffered acid and showed altered regulation of

Autophagy attenuates the catabolic effect during inflammatory conditions in nucleus pulposus cells, as sustained by NF-κB and JNK inhibition

Science.gov (United States)

XU, KANG; CHEN, WEIJIAN; WANG, XIAOFEI; PENG, YAN; LIANG, ANJING; HUANG, DONGSHENG; LI, CHUNHAI; YE, WEI

2015-01-01

Proteoglycan degradation contributing to the pathogenesis of intervertebral disc (IVD) degeneration is induced by inflammatory cytokines, such as tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β). Cell autophagy exists in degenerative diseases, including osteoarthritis and inter-vertebral disc degeneration. However, the autophagy induced by TNF-α and IL-1β and the corresponding molecular mechanism appear to be cell-type dependent. The effect and mechanism of autophagy regulated by TNF-α and IL-1β in IVDs remains unclear. Additionally, the impact of autophagy on the catabolic effect in inflammatory conditions also remains elusive. In the present study, autophagy activator and inhibitor were used to demonstrate the impact of autophagy on the catabolic effect induced by TNF-α. A critical role of autophagy was identified in rat nucleus pulposus (NP) cells: Inhibition of autophagy suppresses, while activation of autophagy enhances, the catabolic effect of cytokines. Subsequently, the autophagy-related gene expression in rat NP cells following TNF-α and IL-1β treatment was observed using immunofluorescence, quantitative polymerase chain reaction and western blot analysis; however, no association was present. In addition, nuclear factor κB (NF-κB), c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinases and p38 mitogen-activated protein kinase inhibitors and TNF-α were used to determine the molecular mechanism of autophagy during the inflammatory conditions, and only the NF-κB and JNK inhibitor were found to enhance the autophagy of rat NP cells. Finally, IKKβ knockdown was used to further confirm the effect of the NF-κB signal on human NP cells autophagy, and the data showed that IKKβ knockdown upregulated the autophagy of NP cells during inflammatory conditions. PMID:26165348

Natural Variation in Synthesis and Catabolism Genes Influences Dhurrin Content in Sorghum

Directory of Open Access Journals (Sweden)

Chad M. Hayes

2015-07-01

Full Text Available Cyanogenic glucosides are natural compounds found in more than 1000 species of angiosperms that produce HCN and are deemed undesirable for agricultural use. However, these compounds are important components of the primary defensive mechanisms of many plant species. One of the best-studied cyanogenic glucosides is dhurrin [(--hydroxymandelonitrile-β--glucopyranoside], which is produced primarily in sorghum [ (L. Moench]. The biochemical basis for dhurrin metabolism is well established; however, little information is available on its genetic control. Here, we dissect the genetic control of leaf dhurrin content through a genome-wide association study (GWAS using a panel of 700 diverse converted sorghum lines (conversion panel previously subjected to pre-breeding and selected for short stature (∼1 m in height and photoperiod insensitivity. The conversion panel was grown for 2 yr in three environments. Wide variation for leaf dhurrin content was found in the sorghum conversion panel, with the Caudatum group exhibiting the highest dhurrin content and the Guinea group showing the lowest dhurrin content. A GWAS using a mixed linear model revealed significant associations (a false discovery rate [FDR] < 0.05 close to both UGT 185B1 in the canonical biosynthetic gene cluster on chromosome 1 and close to the catabolic dhurrinase loci on chromosome 8. Dhurrin content was associated consistently with biosynthetic genes in the two N-fertilized environments, while dhurrin content was associated with catabolic loci in the environment without supplemental N. These results suggest that genes for both biosynthesis and catabolism are important in determining natural variation for leaf dhurrin in sorghum in different environments.

Biodistribution and catabolism of 18F-labelled isopeptide N(epsilon)-(gamma-glutamyl)-L-lysine.

Science.gov (United States)

Hultsch, C; Bergmann, R; Pawelke, B; Pietzsch, J; Wuest, F; Johannsen, B; Henle, T

2005-12-01

Isopeptide bonds between the epsilon-amino group of lysine and the gamma-carboxamide group of glutamine are formed during strong heating of pure proteins or, more important, by enzymatic reaction mediated by transglutaminases. Despite the wide use of a microbial transglutaminase in food biotechnology, up to now little is known about the metabolic fate of the isopeptide N(epsilon)-(gamma-glutamyl)-L-lysine. In the present study, N-succinimidyl-4-[(18)F]fluorobenzoate was used to modify N(epsilon)-(gamma-glutamyl)-L-lysine at each of its two alpha-amino groups, resulting in the 4-[(18)F]fluorobenzoylated derivatives, for which biodistribution, catabolism, and elimination were investigated in male Wistar rats. A significant different biochemical behavior of the two labelled isopeptides was observed in terms of in vitro stability, in vivo metabolism as well as biodistribution. The results suggest that the metabolic fate of isopeptides is likely to be dependent on how they are reabsorbed - free or peptide bound.

Molecular and genetic characterization of the rhizopine catabolism (mocABRC) genes of Rhizobium meliloti L5-30.

Science.gov (United States)

Rossbach, S; Kulpa, D A; Rossbach, U; de Bruijn, F J

1994-10-17

Rhizopine (L-3-O-methyl-scyllo-inosamine, 3-O-MSI) is a symbiosis-specific compound, which is synthesized in nitrogen-fixing nodules of Medicago sativa induced by Rhizobium meliloti strain L5-30. 3-O-MSI is thought to function as an unusual growth substrate for R. meliloti L5-30, which carries a locus (mos) responsible for its synthesis closely linked to a locus (moc) responsible for its degradation. Here, the essential moc genes were delimited by Tn5 mutagenesis and shown to be organized into two regions, separated by 3 kb of DNA. The DNA sequence of a 9-kb fragment spanning the two moc regions was determined, and four genes were identified that play an essential role in rhizopine catabolism (mocABC and mocR). The analysis of the DNA sequence and the amino acid sequence of the deduced protein products revealed that MocA resembles NADH-dependent dehydrogenases. MocB exhibits characteristic features of periplasmic-binding proteins that are components of high-affinity transport systems. MocC does not share significant homology with any protein in the database. MocR shows homology with the GntR class of bacterial regulator proteins. These results suggest that the mocABC genes are involved in the uptake and subsequent degradation of rhizopine, whereas mocR is likely to play a regulatory role.

Biochanin-A antagonizes the interleukin-1β-induced catabolic inflammation through the modulation of NFκB cellular signaling in primary rat chondrocytes

Energy Technology Data Exchange (ETDEWEB)

Oh, Ji-Su [Department of Oral and Maxillofacial Surgery, Chosun University, Gwangju, 61452 (Korea, Republic of); Cho, In-A; Kang, Kyeong-Rok [Department of Dental Bioengineering, Chosun University, Gwangju, 61452 (Korea, Republic of); You, Jae-Seek [Department of Oral and Maxillofacial Surgery, Chosun University, Gwangju, 61452 (Korea, Republic of); Yu, Sang-Joun [Department of Periodontology, Chosun University, Gwangju, 61452 (Korea, Republic of); Lee, Gyeong-Je [Department of Prosthodontics, Chosun University, Gwangju, 61452 (Korea, Republic of); Seo, Yo-Seob [Department of Oral and Maxillofacial Radiology, Chosun University, Gwangju, 61452 (Korea, Republic of); Kim, Chun Sung; Kim, Do Kyung [Pre-Dentistry, School of Dentistry, Chosun University, Gwangju, 61452 (Korea, Republic of); Kim, Su-Gwan [Department of Oral and Maxillofacial Surgery, Chosun University, Gwangju, 61452 (Korea, Republic of); Seo, Young-Woo [Korea Basic Science Institute, Gwangju Center, Chonnam National University, Gwangju, 61186 (Korea, Republic of); Im, Hee-Jeong [Department of Biochemistry, Rush University Medical Center, Chicago, IL, 60612 (United States); Kim, Jae-Sung, E-mail: js_kim@chosun.ac.kr [Pre-Dentistry, School of Dentistry, Chosun University, Gwangju, 61452 (Korea, Republic of)

2016-09-02

Biochanin-A, a phytoestrogen derived from herbal plants, protected from the IL-1β-induced loss of proteoglycans through the suppression of matrix degrading enzymes such as matrix metalloproteinase (MMP)-13, MMP-3, MMP-1, and ADAMTS-5 in primary rat chondrocytes and the knee articular cartilage. It also suppressed the expression of IL-1β-induced catabolic factors such as nitric oxide synthase 2, cyclooxygenase-2, prostaglandin E{sub 2}, and inflammatory cytokines. Furthermore, biochanin-A suppressed the IL-1β-induced phosphorylation of NFκB, and inhibited its nuclear translocation in primary rat chondrocytes. These results indicate that biochanin-A antagonizes the IL-1β-induced catabolic effects through its anti-inflammatory activity that involves the modulation of NFκB signaling. - Highlights: • Biochanin-A is a phytoestrogen derived from medicinal plants. • It suppressed the IL-1β-induced matrix degrading enzymes and catabolic factors. • It inhibited IL-1β-induced proteoglycan loss in chondrocytes and cartilage tissues. • Its anti-catabolic effects were mediated by modulation of NFκB signaling. • It may be used as a potential anti-catabolic biomaterial for osteoarthritis.

Jelly-type carbohydrate supplement in healthy subjects suppresses the catabolism of adipose tissue and muscle protein and improves their satisfactions

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Takuro Oyama

2018-06-01

Full Text Available Summary: Background & aims: Many studies have reported the effects of preoperative clear fluid carbohydrate supplements; however, few studies have reported the effects of preoperative jelly-type carbohydrate supplements. This study aimed to assess the effect of a jelly-type oral nutritional supplement (ONS on metabolism, redox balance by using various surrogate markers and to evaluate its excretion from the stomach. Methods: This study was conducted according to a crossover design. Participants underwent a control experiment whereby they fasted after dinner and only ingested water until the experiment. The remaining participants underwent an ONS experiment whereby they ingested 400 g of ONS before bed and another 400 g at 7:00 am. Blood samples were collected at 9:00 am. After a break of at least 24 h, participants underwent the alternate experiment. Results: Thirty minutes after intake of jelly, the gastric antrum appeared flat (the same result as that at baseline on ultrasonography. The ONS group showed significantly lower serum free fatty acid levels (100 μEq/L, p = 0.027, vs. 327 μEq/L, n = 6, total ketone bodies levels, 3-MH/creatinine levels, and oxidative stress surrogate markers. Serum insulin levels were significantly higher and participant's satisfaction was improved in the ONS group. Conclusions: We have the limitations of our methodologies as surrogate markers, compared with direct measurement of lipolysis, proteolysis and redox balance regulation. But Jelly-type ONS suppresses the catabolism of adipose tissue and muscle protein, decreases oxidative stress and improves patient satisfaction in healthy participants, without any increased risk of aspiration. Keywords: Crossover design, Jelly-type oral nutritional supplement, Metabolism, Antioxidation, ERAS

Novel Insights into the Diversity of Catabolic Metabolism from Ten Haloarchaeal Genomes

Energy Technology Data Exchange (ETDEWEB)

Anderson, Iain; Scheuner, Carmen; Goker, Markus; Mavromatis, Kostas; Hooper, Sean D.; Porat, Iris; Klenk, Hans-Peter; Ivanova, Natalia; Kyrpides, Nikos

2011-05-03

The extremely halophilic archaea are present worldwide in saline environments and have important biotechnological applications. Ten complete genomes of haloarchaea are now available, providing an opportunity for comparative analysis. We report here the comparative analysis of five newly sequenced haloarchaeal genomes with five previously published ones. Whole genome trees based on protein sequences provide strong support for deep relationships between the ten organisms. Using a soft clustering approach, we identified 887 protein clusters present in all halophiles. Of these core clusters, 112 are not found in any other archaea and therefore constitute the haloarchaeal signature. Four of the halophiles were isolated from water, and four were isolated from soil or sediment. Although there are few habitat-specific clusters, the soil/sediment halophiles tend to have greater capacity for polysaccharide degradation, siderophore synthesis, and cell wall modification. Halorhabdus utahensis and Haloterrigena turkmenica encode over forty glycosyl hydrolases each, and may be capable of breaking down naturally occurring complex carbohydrates. H. utahensis is specialized for growth on carbohydrates and has few amino acid degradation pathways. It uses the non-oxidative pentose phosphate pathway instead of the oxidative pathway, giving it more flexibility in the metabolism of pentoses. These new genomes expand our understanding of haloarchaeal catabolic pathways, providing a basis for further experimental analysis, especially with regard to carbohydrate metabolism. Halophilic glycosyl hydrolases for use in biofuel production are more likely to be found in halophiles isolated from soil or sediment.

Endogenous protein "barcode" for data validation and normalization in quantitative MS analysis.

Science.gov (United States)

Lee, Wooram; Lazar, Iulia M

2014-07-01

Quantitative proteomic experiments with mass spectrometry detection are typically conducted by using stable isotope labeling and label-free quantitation approaches. Proteins with housekeeping functions and stable expression level such actin, tubulin, and glyceraldehyde-3-phosphate dehydrogenase are frequently used as endogenous controls. Recent studies have shown that the expression level of such common housekeeping proteins is, in fact, dependent on various factors such as cell type, cell cycle, or disease status and can change in response to a biochemical stimulation. The interference of such phenomena can, therefore, substantially compromise their use for data validation, alter the interpretation of results, and lead to erroneous conclusions. In this work, we advance the concept of a protein "barcode" for data normalization and validation in quantitative proteomic experiments. The barcode comprises a novel set of proteins that was generated from cell cycle experiments performed with MCF7, an estrogen receptor positive breast cancer cell line, and MCF10A, a nontumorigenic immortalized breast cell line. The protein set was selected from a list of ~3700 proteins identified in different cellular subfractions and cell cycle stages of MCF7/MCF10A cells, based on the stability of spectral count data generated with an LTQ ion trap mass spectrometer. A total of 11 proteins qualified as endogenous standards for the nuclear and 62 for the cytoplasmic barcode, respectively. The validation of the protein sets was performed with a complementary SKBR3/Her2+ cell line.

Protein and leucine metabolism in maple syrup urine disease

International Nuclear Information System (INIS)

Thompson, G.N.; Bresson, J.L.; Pacy, P.J.; Bonnefont, J.P.; Walter, J.H.; Leonard, J.V.; Saudubray, J.M.; Halliday, D.

1990-01-01

Constant infusions of [13C]leucine and [2H5]phenylalanine were used to trace leucine and protein kinetics, respectively, in seven children with maple syrup urine disease (MSUD) and eleven controls matched for age and dietary protein intake. Despite significant elevations of plasma leucine (mean 351 mumol/l, range 224-477) in MSUD subjects, mean whole body protein synthesis [3.78 +/- 0.42 (SD) g.kg-1. 24 h-1] and catabolism (4.07 +/- 0.46) were similar to control values (3.69 +/- 0.50 and 4.09 +/- 0.50, respectively). The relationship between phenylalanine and leucine fluxes was also similar in MSUD subjects (mean phenylalanine-leucine flux ratio 0.35 +/- 0.07) and previously reported adult controls (0.33 +/- 0.02). Leucine oxidation was undetectable in four of the MSUD subjects and very low in the other three (less than 4 mumol.kg-1.h-1; controls 13-20). These results show that persistent elevation in leucine concentration has no effect on protein synthesis. The marked disturbance in leucine metabolism in MSUD did not alter the relationship between rates of catabolism of protein to phenylalanine and leucine, which provides further support for the validity of the use of a single amino acid to trace whole body protein metabolism. The minimal leucine oxidation in MSUD differs from findings in other inborn metabolic errors and indicates that in patients with classical MSUD there is no significant route of leucine disposal other than through protein synthesis

Re-Factoring Glycolytic Genes for Targeted Engineering of Catabolism in Gram-Negative Bacteria

DEFF Research Database (Denmark)

Sánchez-Pascuala, Alberto; Nikel, Pablo I.; de Lorenzo, Víctor

2018-01-01

the potential applications of such a portable tool for targeted pathway engineering, in the present protocol we describe how the genes encoding all the enzymes of the linear EMP route have been individually recruited from the genome of E. coli K-12, edited in silico to remove their endogenous regulatory signals......The Embden-Meyerhof-Parnas (EMP) pathway is widely accepted to be the biochemical standard of glucose catabolism. The well-characterized glycolytic route of Escherichia coli, based on the EMP catabolism, is an example of an intricate pathway in terms of genomic organization of the genes involved...... and patterns of gene expression and regulation. This intrinsic genetic and metabolic complexity renders it difficult to engineer glycolytic activities and transfer them onto other microbial cell factories, thus limiting the biotechnological potential of bacterial hosts that lack the route. Taking into account...

Muscle protein turnover in rats treated with corticosterone (CC) or/and nandrolone decanoate (ND) and fed an adequate or a low-protein diet

Energy Technology Data Exchange (ETDEWEB)

Santidrian, S.; Cuevillas, F.; Goena, M.; Larralde, J.

1986-03-01

In order to investigate the possible antagonistic effect between glucocorticoids and androgens on muscle protein turnover, the authors have measured the fractional rates of gastrocnemius muscle protein synthesis (k/sub s/) and degradation (k/sub d/) by the constant-intravenous-infusion method using L-//sup 14/C/-tyrosine in rats receiving via s.c. per 100 g b.wt. 10 mg of CC, or 2 mg of ND or CC+ND at the indicated doses, and fed either an 18% or 5% protein diets over a period of 5 days. As an additional index of protein synthesis, RNA activity (g of synthesized protein/day/g RNA) was determined as well. Results showed that as compared to vehicle-injected animals fed the adequate diet, CC-treated rats exhibited a reduction of muscle k/sub d/, while ND-treated rats had an outstanding increase of muscle k/sub s/. However, rats receiving CC+ND showed k/sub s/ and k/sub d/ values similar to those displayed by control animals. Nevertheless, when the steroids were injected to rats fed the low-protein diet, CC has a catabolic effect on muscle protein but by reducing k/sub s/, while the anabolic action of ND is still displayed but by a significant reduction of muscle k/sub d/. CC+ND given to these protein-deficient rats caused an increase in muscle k/sub s/ and a reduction in k/sub d/. These results might indicate that, at least in part, ND antagonizes the catabolic action of high doses of CC on muscle protein metabolism.

Muscle protein turnover in rats treated with corticosterone (CC) or/and nandrolone decanoate (ND) and fed an adequate or a low-protein diet

International Nuclear Information System (INIS)

Santidrian, S.; Cuevillas, F.; Goena, M.; Larralde, J.

1986-01-01

In order to investigate the possible antagonistic effect between glucocorticoids and androgens on muscle protein turnover, the authors have measured the fractional rates of gastrocnemius muscle protein synthesis (k/sub s/) and degradation (k/sub d/) by the constant-intravenous-infusion method using L-/ 14 C/-tyrosine in rats receiving via s.c. per 100 g b.wt. 10 mg of CC, or 2 mg of ND or CC+ND at the indicated doses, and fed either an 18% or 5% protein diets over a period of 5 days. As an additional index of protein synthesis, RNA activity (g of synthesized protein/day/g RNA) was determined as well. Results showed that as compared to vehicle-injected animals fed the adequate diet, CC-treated rats exhibited a reduction of muscle k/sub d/, while ND-treated rats had an outstanding increase of muscle k/sub s/. However, rats receiving CC+ND showed k/sub s/ and k/sub d/ values similar to those displayed by control animals. Nevertheless, when the steroids were injected to rats fed the low-protein diet, CC has a catabolic effect on muscle protein but by reducing k/sub s/, while the anabolic action of ND is still displayed but by a significant reduction of muscle k/sub d/. CC+ND given to these protein-deficient rats caused an increase in muscle k/sub s/ and a reduction in k/sub d/. These results might indicate that, at least in part, ND antagonizes the catabolic action of high doses of CC on muscle protein metabolism

A protocatechuate biosensor for Pseudomonas putida KT2440 via promoter and protein evolution

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Ramesh K. Jha

2018-06-01

Full Text Available Robust fluorescence-based biosensors are emerging as critical tools for high-throughput strain improvement in synthetic biology. Many biosensors are developed in model organisms where sophisticated synthetic biology tools are also well established. However, industrial biochemical production often employs microbes with phenotypes that are advantageous for a target process, and biosensors may fail to directly transition outside the host in which they are developed. In particular, losses in sensitivity and dynamic range of sensing often occur, limiting the application of a biosensor across hosts. Here we demonstrate the optimization of an Escherichia coli-based biosensor in a robust microbial strain for the catabolism of aromatic compounds, Pseudomonas putida KT2440, through a generalizable approach of modulating interactions at the protein-DNA interface in the promoter and the protein-protein dimer interface. The high-throughput biosensor optimization approach demonstrated here is readily applicable towards other allosteric regulators. Keywords: Whole cell biosensor, Aromatic catabolism, Transcription factor, PcaU, Shikimate

Effects of intraoperative administration of carbohydrates during long-duration oral and maxillofacial surgery on the metabolism of carbohydrates, proteins, and lipids.

Science.gov (United States)

Yamamoto, Toru; Yoshida, Mitsuhiro; Watanabe, Seiji; Kawahara, Hiroshi

2015-12-01

Insulin resistance in patients undergoing invasive surgery impairs glucose and lipid metabolism and increases muscle protein catabolism, which may result in delayed recovery and prolonged hospital stay. We examined whether intraoperative administration of carbohydrates during long-duration oral and maxillofacial surgery under general anesthesia affects carbohydrate, proteins, and lipid metabolism and the length of hospital stay. We studied 16 patients with normal liver, kidney, and endocrine functions, and ASA physical status I or II, but without diabetes. Patients were randomly assigned to receive 0.1 g/kg/h of (n = 8) or lactated Ringer's solution (n = 8). Blood was collected before (T0) and 4 h after (T1) the start of surgery. We analyzed the plasma levels of glucose, ketone bodies, 3-methylhistidine (3-MH), and the length of hospital stay. At T0, no statistically significant differences were observed in the levels of glucose, ketone bodies, and 3-MH between the groups. At T1, no statistically significant difference in glucose levels was found between the groups. However, ketone bodies were significantly lower, and the changes in 3-MH levels were significantly less pronounced in the glucose-treated group compared with controls. No significant differences were observed between the groups in terms of length of hospital stay. The administration of low doses of glucose during surgery was safe, did not cause hyperglycemia or hypoglycemia, and inhibited lipid metabolism and protein catabolism. Additional experiments with larger cohorts will be necessary to investigate whether intraoperative management with glucose facilitates postoperative recovery of patients with oral cancer.

D-Allose catabolism of Escherichia coli

DEFF Research Database (Denmark)

Poulsen, Tim S.; Chang, Ying-Ying; Hove-Jensen, Bjarne

1999-01-01

Genes involved in allose utilization of Escherichia coli K-12 are organized in at least two operons, alsRBACE and alsI, located next to each other on the chromosome but divergently transcribed. Mutants defective in alsI (allose 6-phosphate isomerase gene) and alsE (allulose 6-phosphate epimerase...... gene) were Als-. Transcription of the two allose operons, measured as β-galactosidase activity specified by alsI-lacZ+ or alsE-lacZ+ operon fusions, was induced by allose. Ribose also caused derepression of expression of the regulon under conditions in which ribose phosphate catabolism was impaired....

CONSTRUCTION AND ANALYSIS OF IPBR/XYLS HYBRID REGULATORY PROTEINS

Science.gov (United States)

IpbR and XylS are related regulatory proteins (having 56% identity). IpbR responds to isopropylbenzene as well as to a variety of hydrophobic chemicals to activate expression of the isopropylbenzene catabolic pathway operon of pRE4 from ipbOP. XylS responds to substituted benzoic...

Roles of gibberellin catabolism and signaling in growth and physiological response to drought and short-day photoperiods in Populus trees.

Directory of Open Access Journals (Sweden)

Christine Zawaski

Full Text Available Survival and productivity of perennial plants in temperate zones are dependent on robust responses to prolonged and seasonal cycles of unfavorable conditions. Here we report whole-genome microarray, expression, physiological, and transgenic evidence in hybrid poplar (Populus tremula × Populus alba showing that gibberellin (GA catabolism and repressive signaling mediates shoot growth inhibition and physiological adaptation in response to drought and short-day (SD induced bud dormancy. Both water deprivation and SDs elicited activation of a suite of poplar GA2ox and DELLA encoding genes. Poplar transgenics with up-regulated GA 2-oxidase (GA2ox and DELLA domain proteins showed hypersensitive growth inhibition in response to both drought and SDs. In addition, the transgenic plants displayed greater drought resistance as evidenced by increased pigment concentrations (chlorophyll and carotenoid and reductions in electrolyte leakage (EL. Comparative transcriptome analysis using whole-genome microarray showed that the GA-deficiency and GA-insensitivity, SD-induced dormancy, and drought response in poplar share a common regulon of 684 differentially-expressed genes, which suggest GA metabolism and signaling plays a role in plant physiological adaptations in response to alterations in environmental factors. Our results demonstrate that GA catabolism and repressive signaling represents a major route for control of growth and physiological adaptation in response to immediate or imminent adverse conditions.

Quorum-Dependent Mannopine-Inducible Conjugative Transfer of an Agrobacterium Opine-Catabolic Plasmid

Science.gov (United States)

Wetzel, Margaret E.; Kim, Kun-Soo; Miller, Marilyn; Olsen, Gary J.

2014-01-01

The Ti plasmid in Agrobacterium tumefaciens strain 15955 carries two alleles of traR that regulate conjugative transfer. The first is a functional allele, called traR, that is transcriptionally induced by the opine octopine. The second, trlR, is a nonfunctional, dominant-negative mutant located in an operon that is inducible by the opine mannopine (MOP). Based on these findings, we predicted that there exist wild-type agrobacterial strains harboring plasmids in which MOP induces a functional traR and, hence, conjugation. We analyzed 11 MOP-utilizing field isolates and found five where MOP induced transfer of the MOP-catabolic element and increased production of the acyl-homoserine lactone (acyl-HSL) quormone. The transmissible elements in these five strains represent a set of highly related plasmids. Sequence analysis of one such plasmid, pAoF64/95, revealed that the 176-kb element is not a Ti plasmid but carries genes for catabolism of MOP, mannopinic acid (MOA), agropinic acid (AGA), and the agrocinopines. The plasmid additionally carries all of the genes required for conjugative transfer, including the regulatory genes traR, traI, and traM. The traR gene, however, is not located in the MOP catabolism region. The gene, instead, is monocistronic and located within the tra-trb-rep gene cluster. A traR mutant failed to transfer the plasmid and produced little to no quormone even when grown with MOP, indicating that TraRpAoF64/95 is the activator of the tra regulon. A traM mutant was constitutive for transfer and acyl-HSL production, indicating that the anti-activator function of TraM is conserved. PMID:24363349

ATP catabolism by tissue nonspecific alkaline phosphatase contributes to development of ARDS in influenza-infected mice.

Science.gov (United States)

Woods, Parker S; Doolittle, Lauren M; Hickman-Davis, Judy M; Davis, Ian C

2018-01-01

Influenza A viruses are highly contagious respiratory pathogens that are responsible for significant morbidity and mortality worldwide on an annual basis. We have shown previously that influenza infection of mice leads to increased ATP and adenosine accumulation in the airway lumen. Moreover, we demonstrated that A 1 -adenosine receptor activation contributes significantly to influenza-induced acute respiratory distress syndrome (ARDS). However, we found that development of ARDS in influenza-infected mice does not require catabolism of ATP to adenosine by ecto-5'-nucleotidase (CD73). Hence, we hypothesized that increased adenosine generation in response to infection is mediated by tissue nonspecific alkaline phosphatase (TNAP), which is a low-affinity, high-capacity enzyme that catabolizes nucleotides in a nonspecific manner. In the current study, we found that whole lung and BALF TNAP expression and alkaline phosphatase enzymatic activity increased as early as 2 days postinfection (dpi) of C57BL/6 mice with 10,000 pfu/mouse of influenza A/WSN/33 (H1N1). Treatment at 2 and 4 dpi with a highly specific quinolinyl-benzenesulfonamide TNAP inhibitor (TNAPi) significantly reduced whole lung alkaline phosphatase activity at 6 dpi but did not alter TNAP gene or protein expression. TNAPi treatment attenuated hypoxemia, lung dysfunction, histopathology, and pulmonary edema at 6 dpi without impacting viral replication or BALF adenosine. Treatment also improved epithelial barrier function and attenuated cellular and humoral immune responses to influenza infection. These data indicate that TNAP inhibition can attenuate influenza-induced ARDS by reducing inflammation and fluid accumulation within the lung. They also further emphasize the importance of adenosine generation for development of ARDS in influenza-infected mice.

Effect of plaster cast immobilization on the turnover rates of soluble proteins and lactate dehydrogenase isoenzymes of rabbit M. soleus

Energy Technology Data Exchange (ETDEWEB)

Edes, I.; Dosa, E.; Sohar, I.; Guba, F. (Orvostudomanyi Egyetem, Szeged (Hungary). Biokemiai Tanszek)

1982-01-01

In atrophized muscle the decreases of the activity of LDH isoenzymes can be explained partly by a 15 per cent decrease of the enzyme synthesis and partly by a 25 per cent increase in catabolism. The quantities of the soluble proteins and LDH were measured after intravenously administered /sup 3/H-leucin incorporation, from the musculus soleus. LDH was isolated by means of affinity chromatography. Radioactivity was determined in a Packard Tri-Carb scintillation counter. The synthesis rate of soluble proteins barely changed during immobilization. In the atrophized muscle the decrease of the amount of soluble proteins could be almost exclusively interpreted in terms of a 25 per cent enchancement of degradative process. The accelerated catabolism is most probably due to the proteolytic enzymes activated by immobilization.

Simple generic model for dynamic experiments with Saccharomyces cerevisiae in continuous culture. Decoupling between anabolism and catabolism

DEFF Research Database (Denmark)

Duboc, Philippe Jean; von Stockar, U.; Villadsen, John

1998-01-01

The dynamic behavior of a continuous culture of Saccharomyces cerevisiae subjected to a sudden increase in the dilution rate has been successfully modelled for anaerobic growth on glucose, and for aerobic growth on acetate, on ethanol, and on glucose. The catabolism responded by an immediate jump...... identified in steady state continuous cultures or during batch experiments. Only the time constant of biosynthesis regeneration, tau(x), and the time constant of catabolic capacity regeneration, tau(cat), had to be identified during transient experiments. In most experiments 7, was around 3 h, and tau(cat...

3-Methylhistidine excretion in myotonic dystrophy

Energy Technology Data Exchange (ETDEWEB)

Griggs, R.C.; Moxley, R.T. III; Forbes, G.B.

1980-12-01

3-Methylhistidine (3-MH) excretion reflects the rate of muscle protein catabolism, since 3-MH occurs almost exclusively in muscle actin and myosin and is not reutilized or catabolized. We studied 3-MH excretion in 9 patients with myotonic dystrophy, 8 normals, and 10 disease controls with Duchenne dystrophy and other disorders. 3-MH excretion was expressed relative to muscle mass as determined by both urinary creatinine and total body potassium (/sup 40/K method). Absolute 3-MH excretion was decreased in myotonic dystrophy patients but was normal when related to muscle mass. The finding of normal 3-MH excretion in myotonic dystrophy suggests that the muscle wasting in this disorder results from impaired anabolic processes rather than accelerated muscle destruction.

3-Methylhistidine excretion in myotonic dystrophy

International Nuclear Information System (INIS)

Griggs, R.C.; Moxley, R.T. III; Forbes, G.B.

1980-01-01

3-Methylhistidine (3-MH) excretion reflects the rate of muscle protein catabolism, since 3-MH occurs almost exclusively in muscle actin and myosin and is not reutilized or catabolized. We studied 3-MH excretion in 9 patients with myotonic dystrophy, 8 normals, and 10 disease controls with Duchenne dystrophy and other disorders. 3-MH excretion was expressed relative to muscle mass as determined by both urinary creatinine and total body potassium ( 40 K method). Absolute 3-MH excretion was decreased in myotonic dystrophy patients but was normal when related to muscle mass. The finding of normal 3-MH excretion in myotonic dystrophy suggests that the muscle wasting in this disorder results from impaired anabolic processes rather than accelerated muscle destruction

Expression and function of the protein tyrosine phosphatase receptor J (PTPRJ in normal mammary epithelial cells and breast tumors.

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Chanel E Smart

Full Text Available The protein tyrosine phosphatase receptor J, PTPRJ, is a tumor suppressor gene that has been implicated in a range of cancers, including breast cancer, yet little is known about its role in normal breast physiology or in mammary gland tumorigenesis. In this paper we show that PTPRJ mRNA is expressed in normal breast tissue and reduced in corresponding tumors. Meta-analysis revealed that the gene encoding PTPRJ is frequently lost in breast tumors and that low expression of the transcript associated with poorer overall survival at 20 years. Immunohistochemistry of PTPRJ protein in normal human breast tissue revealed a distinctive apical localisation in the luminal cells of alveoli and ducts. Qualitative analysis of a cohort of invasive ductal carcinomas revealed retention of normal apical PTPRJ localization where tubule formation was maintained but that tumors mostly exhibited diffuse cytoplasmic staining, indicating that dysregulation of localisation associated with loss of tissue architecture in tumorigenesis. The murine ortholog, Ptprj, exhibited a similar localisation in normal mammary gland, and was differentially regulated throughout lactational development, and in an in vitro model of mammary epithelial differentiation. Furthermore, ectopic expression of human PTPRJ in HC11 murine mammary epithelial cells inhibited dome formation. These data indicate that PTPRJ may regulate differentiation of normal mammary epithelia and that dysregulation of protein localisation may be associated with tumorigenesis.

Characterization of the mycobacterial acyl-CoA carboxylase holo complexes reveals their functional expansion into amino acid catabolism.

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Matthias T Ehebauer

2015-02-01

Full Text Available Biotin-mediated carboxylation of short-chain fatty acid coenzyme A esters is a key step in lipid biosynthesis that is carried out by multienzyme complexes to extend fatty acids by one methylene group. Pathogenic mycobacteria have an unusually high redundancy of carboxyltransferase genes and biotin carboxylase genes, creating multiple combinations of protein/protein complexes of unknown overall composition and functional readout. By combining pull-down assays with mass spectrometry, we identified nine binary protein/protein interactions and four validated holo acyl-coenzyme A carboxylase complexes. We investigated one of these--the AccD1-AccA1 complex from Mycobacterium tuberculosis with hitherto unknown physiological function. Using genetics, metabolomics and biochemistry we found that this complex is involved in branched amino-acid catabolism with methylcrotonyl coenzyme A as the substrate. We then determined its overall architecture by electron microscopy and found it to be a four-layered dodecameric arrangement that matches the overall dimensions of a distantly related methylcrotonyl coenzyme A holo complex. Our data argue in favor of distinct structural requirements for biotin-mediated γ-carboxylation of α-β unsaturated acid esters and will advance the categorization of acyl-coenzyme A carboxylase complexes. Knowledge about the underlying structural/functional relationships will be crucial to make the target category amenable for future biomedical applications.

Catabolism of pyrimidines in yeast: A tool to understand degradation of anticancer drugs

DEFF Research Database (Denmark)

Andersen, Gorm; Merico, A.; Bjornberg, O.

2006-01-01

The pyrimidine catabolic pathway is of crucial importance in cancer patients because it is involved in degradation of several chemotherapeutic drugs, such as 5-fluorouracil; it also is important in plants, unicellular eukaryotes, and bacteria for the degradation of pyrimidine-based biocides/antib...

Identification of two gene clusters and a transcriptional regulator required for Pseudomonas aeruginosa glycine betaine catabolism.

Science.gov (United States)

Wargo, Matthew J; Szwergold, Benjamin S; Hogan, Deborah A

2008-04-01

Glycine betaine (GB), which occurs freely in the environment and is an intermediate in the catabolism of choline and carnitine, can serve as a sole source of carbon or nitrogen in Pseudomonas aeruginosa. Twelve mutants defective in growth on GB as the sole carbon source were identified through a genetic screen of a nonredundant PA14 transposon mutant library. Further growth experiments showed that strains with mutations in two genes, gbcA (PA5410) and gbcB (PA5411), were capable of growth on dimethylglycine (DMG), a catabolic product of GB, but not on GB itself. Subsequent nuclear magnetic resonance (NMR) experiments with 1,2-(13)C-labeled choline indicated that these genes are necessary for conversion of GB to DMG. Similar experiments showed that strains with mutations in the dgcAB (PA5398-PA5399) genes, which exhibit homology to genes that encode other enzymes with demethylase activity, are required for the conversion of DMG to sarcosine. Mutant analyses and (13)C NMR studies also confirmed that the soxBDAG genes, predicted to encode a sarcosine oxidase, are required for sarcosine catabolism. Our screen also identified a predicted AraC family transcriptional regulator, encoded by gbdR (PA5380), that is required for growth on GB and DMG and for the induction of gbcA, gbcB, and dgcAB in response to GB or DMG. Mutants defective in the previously described gbt gene (PA3082) grew on GB with kinetics similar to those of the wild type in both the PAO1 and PA14 strain backgrounds. These studies provided important insight into both the mechanism and the regulation of the catabolism of GB in P. aeruginosa.

Serum uric acid, protein intake and mortality in hemodialysis patients.

Science.gov (United States)

Park, Christina; Obi, Yoshitsugu; Streja, Elani; Rhee, Connie M; Catabay, Christina J; Vaziri, Nosratola D; Kovesdy, Csaba P; Kalantar-Zadeh, Kamyar

2017-10-01

The association between serum uric acid (SUA) and mortality has been conflicting among studies using hemodialysis (HD) patients. Given the close link between purine and protein in foods, we hypothesized that normalized protein catabolic rate (nPCR), a dietary protein intake surrogate, modifies the SUA-mortality association in the HD population. We identified 4298 patients who initiated HD and had one or more SUA measurement in a contemporary cohort of HD patients over 5 years (1 January 2007-31 December 2011), and examined survival probability according to the first uric acid measurement, adjusting for dialysis vintage, case-mix and malnutrition-inflammation complex-related variables. Mean SUA concentration was 6.6 ± 1.8 mg/dL. There was a consistent association of higher SUA with better nutritional status and lower all-cause mortality irrespective of adjusted models (Ptrend 6.0-7.0 mg/dL) showed no significant mortality risk [hazard ratio (HR) 0.90, 95% confidence interval (CI) 0.72-1.13], while the lowest category (HD patients. Contrary to the general population, low but not high SUA is associated with higher all-cause mortality in HD patients, especially in those with low protein intake. Nutritional features of SUA warrant additional studies. © The Author 2017. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

The effect of tranilast on fibroblast activation protein α (FAP-α expression in normal and keloid fibroblasts in vitro

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Paweł P. Antończak

2017-07-01

Full Text Available Introduction . Tranilast (N-(3’,4’-demethoxycinnamoyl-anthranilic acid is an anti-allergic drug. Its mechanism of action is based on the inhibition of antigen-induced release of chemical mediators from mast cells and basophils. It also reveals antifibroproliferative activities. These properties of tranilast are used in the treatment of hypertrophic scars and keloids. Keloids are characterized by incorrect extracellular matrix components turnover. Fibroblasts derived from keloids reveal overproduction of collagen type I and decreased degradation of extracellular matrix in comparison with normal fibroblasts. Fibroblast activation protein α (FAP-α may play an important role in remodeling of extracellular matrix and the invasive properties of keloids. Objective . In the present study, the effect of tranilast on expression of FAP-α gene and its protein was evaluated in normal human dermal fibroblasts and fibroblasts derived from keloids cultured in vitro . Materials and methods. In the first stage of the study, the influence of tranilast on cell viability was estimated. The second stage of the study included the quantitative evaluation of FAP-α mRNA expression in normal and keloid fibroblasts treated with tranilast. The third stage of the study comprised fibroblast activation protein α expression analysis in the examined cells treated with tranilast. Results and conclusions . The expression of FAP-α gene and fibroblast activation protein α is higher in keloid fibroblasts. Tranilast at concentrations of 3 μM and 30 μM up-regulated mRNA FAP-α expression in normal fibroblasts but did not influence keloid fibroblasts. The drug, at concentrations of 30 μM and 300 μM up-regulated fibroblast activation protein α expression in normal fibroblasts and did not influence keloid fibroblasts. Tranilast antiproliferative effect is not associated with FAP-α expression in keloid fibroblasts.

Health issues of whey proteins: 1. Protection of lean body mass

NARCIS (Netherlands)

Schaafsma, G.

2006-01-01

Loss of muscle mass as a consequence of changes in protein metabolism during periods of catabolic stress is a serious complication in a variety of conditions. These conditions are weight loss programs, sarcopenia in the elderly and several clinical states. It appears from many studies that improved

Effects of UVB-induced oxidative stress on protein expression and specific protein oxidation in normal human epithelial keratinocytes: a proteomic approach

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De Marco Federico

2010-03-01

Full Text Available Abstract Background The UVB component of solar ultraviolet irradiation is one of the major risk factors for the development of skin cancer in humans. UVB exposure elicits an increased generation of reactive oxygen species (ROS, which are responsible for oxidative damage to proteins, DNA, RNA and lipids. In order to examine the biological impact of UVB irradiation on skin cells, we used a parallel proteomics approach to analyze the protein expression profile and to identify oxidatively modified proteins in normal human epithelial keratinocytes. Results The expression levels of fifteen proteins - involved in maintaining the cytoskeleton integrity, removal of damaged proteins and heat shock response - were differentially regulated in UVB-exposed cells, indicating that an appropriate response is developed in order to counteract/neutralize the toxic effects of UVB-raised ROS. On the other side, the redox proteomics approach revealed that seven proteins - involved in cellular adhesion, cell-cell interaction and protein folding - were selectively oxidized. Conclusions Despite a wide and well orchestrated cellular response, a relevant oxidation of specific proteins concomitantly occurs in UVB-irradiated human epithelial Keratinocytes. These modified (i.e. likely dysfunctional proteins might result in cell homeostasis impairment and therefore eventually promote cellular degeneration, senescence or carcinogenesis.

Amino acid catabolism and generation of volatiles by lactic acid bacteria

OpenAIRE

Tavaria, F. K.; Dahl, S.; Carballo, F. J.; Malcata, F. X.

2002-01-01

Twelve isolates of lactic acid bacteria, belonging to the Lactobacillus, Lactococcus, Leuconostoc, and Enterococcus genera, were previously isolated from 180- d-old Serra da Estrela cheese, a traditional Portuguese cheese manufactured from raw milk and coagulated with a plant rennet. These isolates were subsequently tested for their ability to catabolize free amino acids, when incubated independently with each amino acid in free form or with a mixture thereof. Attempts...

Aerobic exercise training prevents heart failure-induced skeletal muscle atrophy by anti-catabolic, but not anabolic actions.

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Rodrigo W A Souza

Full Text Available Heart failure (HF is associated with cachexia and consequent exercise intolerance. Given the beneficial effects of aerobic exercise training (ET in HF, the aim of this study was to determine if the ET performed during the transition from cardiac dysfunction to HF would alter the expression of anabolic and catabolic factors, thus preventing skeletal muscle wasting.We employed ascending aortic stenosis (AS inducing HF in Wistar male rats. Controls were sham-operated animals. At 18 weeks after surgery, rats with cardiac dysfunction were randomized to 10 weeks of aerobic ET (AS-ET or to an untrained group (AS-UN. At 28 weeks, the AS-UN group presented HF signs in conjunction with high TNF-α serum levels; soleus and plantaris muscle atrophy; and an increase in the expression of TNF-α, NFκB (p65, MAFbx, MuRF1, FoxO1, and myostatin catabolic factors. However, in the AS-ET group, the deterioration of cardiac function was prevented, as well as muscle wasting, and the atrophy promoters were decreased. Interestingly, changes in anabolic factor expression (IGF-I, AKT, and mTOR were not observed. Nevertheless, in the plantaris muscle, ET maintained high PGC1α levels.Thus, the ET capability to attenuate cardiac function during the transition from cardiac dysfunction to HF was accompanied by a prevention of skeletal muscle atrophy that did not occur via an increase in anabolic factors, but through anti-catabolic activity, presumably caused by PGC1α action. These findings indicate the therapeutic potential of aerobic ET to block HF-induced muscle atrophy by counteracting the increased catabolic state.

Analysis of drug-protein binding using on-line immunoextraction and high-performance affinity microcolumns: Studies with normal and glycated human serum albumin.

Science.gov (United States)

Matsuda, Ryan; Jobe, Donald; Beyersdorf, Jared; Hage, David S

2015-10-16

A method combining on-line immunoextraction microcolumns with high-performance affinity chromatography (HPAC) was developed and tested for use in examining drug-protein interactions with normal or modified proteins. Normal human serum albumin (HSA) and glycated HSA were used as model proteins for this work. High-performance immunoextraction microcolumns with sizes of 1.0-2.0 cm × 2.1mm i.d. and containing anti-HSA polyclonal antibodies were developed and tested for their ability to bind normal HSA or glycated HSA. These microcolumns were able to extract up to 82-93% for either type of protein at 0.05-0.10 mL/min and had a binding capacity of 0.34-0.42 nmol HSA for a 1.0 cm × 2.1mm i.d. microcolumn. The immunoextraction microcolumns and their adsorbed proteins were tested for use in various approaches for drug binding studies. Frontal analysis was used with the adsorbed HSA/glycated HSA to measure the overall affinities of these proteins for the drugs warfarin and gliclazide, giving comparable values to those obtained previously using similar protein preparations that had been covalently immobilized within HPAC columns. Zonal elution competition studies with gliclazide were next performed to examine the specific interactions of this drug at Sudlow sites I and II of the adsorbed proteins. These results were also comparable to those noted in prior work with covalently immobilized samples of normal HSA or glycated HSA. These experiments indicated that drug-protein binding studies can be carried out by using on-line immunoextraction microcolumns with HPAC. The same method could be used in the future with clinical samples and other drugs or proteins of interest in pharmaceutical studies or biomedical research. Copyright © 2015 Elsevier B.V. All rights reserved.

A Murine Model of Persistent Inflammation, Immune Suppression, and Catabolism Syndrome

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Amanda M. Pugh

2017-08-01

Full Text Available Critically ill patients that survive sepsis can develop a Persistent Inflammation, Immunosuppression, and Catabolism Syndrome (PICS, which often leads to extended recovery periods and multiple complications. Here, we utilized a cecal ligation and puncture (CLP method in mice with the goal of creating a model that concurrently displays all the characteristics of PICS. We observed that, after eight days, mice that survive the CLP develop persistent inflammation with significant myelopoiesis in the bone marrow and spleen. These mice also demonstrate ongoing immune suppression, as evidenced by the decreased total and naïve splenic CD4 and CD8 T cells with a concomitant increase in immature myeloid cells. The mice further display significant weight loss and decreased muscle mass, indicating a state of ongoing catabolism. When PICS mice are challenged with intranasal Pseudomonas aeruginosa, mortality is significantly elevated compared to sham mice. This mortality difference is associated with increased bacterial loads in the lung, as well as impaired neutrophil migration and neutrophil dysfunction in the PICS mice. Altogether, we have created a sepsis model that concurrently exhibits PICS characteristics. We postulate that this will help determine the mechanisms underlying PICS and identify potential therapeutic targets to improve outcomes for this patient population.

Effects of whey protein and its two major protein components on satiety and food intake in normal-weight women.

Science.gov (United States)

Chungchunlam, Sylvia M S; Henare, Sharon J; Ganesh, Siva; Moughan, Paul J

2017-06-01

Protein is the most satiating macronutrient and is source dependent, with whey protein thought to be particularly satiating. The purported satiating effect of whey protein may be due to the unique mixture of proteins in whey or to the major constituent individual proteins (β-lactoglobulin and α-lactalbumin). The objective of the study was to compare the effects of isoenergetic (~2100kJ, ~500kcal) preload meals enriched (~50g protein) with either whey protein isolate (WP), β-lactoglobulin (BL) isolate or α-lactalbumin (AL) isolate, on food intake at an ad libitum test meal 120min later and subjective ratings of appetite (hunger, desire to eat, prospective food consumption and fullness) using visual analogue scales (VAS). Twenty adult normal-weight women (mean age 24.2±0.8years; mean BMI 22.7±0.4kg/m 2 ) participated in the study which used a single-blind completely randomised block design, where each subject consumed each of the three preload meals. Energy intake at the ad libitum test meal and total energy intakes (preload+test meal) did not differ between the three preload meals (p>0.05). There were no significant differences observed for the VAS scores and net incremental area under the curve (net iAUC) during the 120min following consumption of the three preload meals for subjective ratings of appetite (p>0.05). The findings show that the satiating effect of whey protein was similar to that of BL or AL individually and suggest that the major whey protein components BL and AL do not mediate the satiating effect of whey protein. The present human trial was registered with the Australian New Zealand Clinical Trials Registry (www.anzctr.org.au) as ACTRN12615000344594. Copyright © 2017 Elsevier Inc. All rights reserved.

Clofibric acid stimulates branched-chain amino acid catabolism by three mechanisms.

Science.gov (United States)

Kobayashi, Rumi; Murakami, Taro; Obayashi, Mariko; Nakai, Naoya; Jaskiewicz, Jerzy; Fujiwara, Yoko; Shimomura, Yoshiharu; Harris, Robert A

2002-11-15

Clofibrate promotes catabolism of branched-chain amino acids by increasing the activity of the branched-chain alpha-keto acid dehydrogenase [BCKDH] complex. Depending upon the sex of the rats, nutritional state, and tissue being studied, clofibrate can affect BCKDH complex activity by three different mechanisms. First, by directly inhibiting BCKDH kinase activity, clofibrate can increase the proportion of the BCKDH complex in the active, dephosphorylated state. This occurs in situations in which the BCKDH complex is largely inactive due to phosphorylation, e.g., in the skeletal muscle of chow-fed rats or in the liver of female rats late in the light cycle. Second, by increasing the levels at which the enzyme components of the BCKDH complex are expressed, clofibrate can increase the total enzymatic activity of the BCKDH complex. This is readily demonstrated in livers of rats fed a low-protein diet, a nutritional condition that induces a decrease in the level of expression of the BCKDH complex. Third, by decreasing the amount of BCKDH kinase expressed and therefore its activity, clofibrate induces an increase in the percentage of the BCKDH complex in the active, dephosphorylated state. This occurs in the livers of rats fed a low-protein diet, a nutritional condition that causes inactivation of the BCKDH complex due to upregulation of the amount of BCKDH kinase. WY-14,643, which, like clofibric acid, is a ligand for the peroxisome-proliferator-activated receptor alpha [PPARalpha], does not directly inhibit BCKDH kinase but produces the same long-term effects as clofibrate on expression of the BCKDH complex and its kinase. Thus, clofibrate is unique in its capacity to stimulate BCAA oxidation through inhibition of BCKDH kinase activity, whereas PPARalpha activators in general promote BCAA oxidation by increasing expression of components of the BCKDH complex and decreasing expression of the BCKDH kinase.

Farnesoid X Receptor Activation Promotes Hepatic Amino Acid Catabolism and Ammonium Clearance in Mice

NARCIS (Netherlands)

Massafra, Vittoria; Milona, Alexandra; Vos, Harmjan R; Ramos, Rúben J J; Gerrits, Johan; Willemsen, Ellen C L; Ramos Pittol, José M; Ijssennagger, Noortje; Houweling, Martin; Prinsen, Hubertus C M T; Verhoeven-Duif, Nanda M; Burgering, Boudewijn M T; van Mil, Saskia W C

2017-01-01

BACKGROUND & AIMS: The nuclear receptor subfamily 1 group H member 4 (NR1H4 or farnesoid X receptor [FXR]) regulates bile acid synthesis, transport, and catabolism. FXR also regulates postprandial lipid and glucose metabolism. We performed quantitative proteomic analyses of liver tissues from mice

Haloacetate analogs of pheromones: effects on catabolism and electrophysiology in Plutella xylostella

International Nuclear Information System (INIS)

Prestwich, G.D.; Streinz, L.

1988-01-01

A series of mono, di-, and trihalogenated acetate analogs of Z11-16:Ac were prepared and examined for electrophysiological activity in antennae of males of the diamondback moth, Plutella xylostella. In addition, two potential affinity labels, a diazoacetate (Dza) and a trifluoromethyl ketone (Tfp), were evaluated for EAG activity. The Z11-16:Ac showed the highest activity in EAG assays, followed by the fluorinated acetates, but other haloacetates were essentially inactive. The effects of these analogs on the hydrolysis of [ 3 H]Z11-16:Ac to [ 3 H]Z11-16:OH by antennal esterases was also examined. The three fluorinated acetates showed the greatest activity as inhibitors in competition assays, with rank order F 2 Ac > F 3 Ac > FAc > AC > Cl 2 Ac > ClAc > Dza > Br 2 Ac > BrAc > Tfp > I > Cl 3 Ac > Br 3 Ac > OH. The relative polarities of the haloacetates, as determined by TLC mobility, are in the order mono- > di- > trihalo, but F, Cl, Br, and I all confer similar polarities within a substitution group. Thus, the steric size appears to be the predominant parameter affecting the interactions of the haloacetate analogs with both receptor and catabolic proteins in P. xylostella males

Structural and metabolic studies of O-linked fucose-containing proteins of normal and virally-transformed rat fibroblasts

International Nuclear Information System (INIS)

Morton, P.A.

1985-01-01

Previous studies in this laboratory have demonstrated that cultured human and rodent cells contain a series of low molecular weight glycosylated amino acids of unusual structure, designated amino acid fucosides. The incorporation of radiolabelled-fucose into one of these components, designated FL4a (glucosylfucosylthreonine), is markedly-reduced in transformed epithelial and fibroblastic cells. The authors have examined fucose-labelled normal and virally-transformed rat fibroblast cell lines for glycoproteins which might be precursors to amino acid fucosides. Using milk alkaline/borohydride treatment (the beta-elimination reaction) to release O-linked oligosaccharides from proteins, they have isolated and partially characterized two low M/sub r/ reaction products (designated DS-ol and TS-ol) released from macromolecular cell material. The identity of one of these components (DS-ol, glucosylfucitol) suggested the existence in these cells of a direct protein precursor to FL4a. They examined fucose-labelled macromolecular cell material for proteins which release DS-ol (DS-proteins.). Using gel filtration chromatography and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) with subsequent autoradiography, they have observed DS-proteins which appear to exhibit a broad molecular weight size range, and are also present in culture medium from normal and transformed cells. The findings suggest that mammalian cells contain DS-proteins and TS-proteins with a novel carbohydrate-peptide linkage wherein L-fucose is O-linked to a polypeptide backbone. Metabolic studies were undertaken to examine both the relationship between DS-protein and FL4a and the biochemical basis for the decreased level of FL4a and the biochemical basis for the decreased level of FL4a observed in transformed cells

Determinants of urea nitrogen production in sepsis. Muscle catabolism, total parenteral nutrition, and hepatic clearance of amino acids.

Science.gov (United States)

Pittiruti, M; Siegel, J H; Sganga, G; Coleman, B; Wiles, C E; Placko, R

1989-03-01

The major determinants of urea production were investigated in 26 patients with multiple trauma (300 studies). The body clearances (CLRs) of ten amino acids (AAs) were estimated as a ratio of muscle-released AAs plus total parenteral nutrition-infused AAs to their extracellular pool. While clinically septic trauma (ST) patients without multiple-organ failure syndrome (MOFS) had a higher level of urea nitrogen production (25.6 +/- 13.4 g of N per day) compared with nonseptic trauma (NST) patients (14 +/- 7.5 g of N per day) and with ST patients with MOFS (4.28 +/- 1.5 g of N per day), in all groups urea N production was found to be a function of muscle protein degradation (catabolism), total parenteral nutrition-administered AAs, and the ratio between leucine CLR and tyrosine CLR (L/T) (r2 = .82, P less than .0001). Since tyrosine is cleared almost exclusively by the liver, the L/T ratio may be regarded as an index of hepatic function. The significant differences between urea N production in ST and NST patients lay in an increased positive dependence on muscle catabolism and increased negative correlation with L/T in the ST group. At any L/T ratio, urea N production was increased in ST patients over NST patients, but in ST patients with MOFS, it fell to or below levels of NST patients. These data show that the ST process is associated with enhancement of ureagenesis, due to increased hepatic CLR of both exogenous and endogenous AAs. In sepsis with MOFS, a marked inhibition of urea synthesis occurs, partially explained by a decreased hepatic CLR of non-branched-chain AAs.

Effects of polyhalogenated aromatic hydrocarbons on vitamin A catabolism and the regulation of vitamin A homeostasis in rats

International Nuclear Information System (INIS)

Bank, P.A.

1989-01-01

Polyhalogenated aromatic hydrocarbons (PHAH) are known to adversely affect vitamin A status resulting in the hepatic depletion and enhanced excretion of vitamin A. Increased renal and serum vitamin A content occurs subsequent to these PHAH-related alterations. Vitamin A, a highly regulated system, appears to undergo rapid compensatory changes to maintain homeostasis in response to nutritional, metabolic, or toxicologic conditions. The present study was undertaken in order to elucidate the mechanism(s) responsible for these PHAH-related effects on vitamin A homeostasis. To this end, the toxin prototype of the PHAH class 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and the 3,4,5,3',4',5'-hexabromo- or hexachloro-biphenyls were used in this study. Results presented in this study indirectly showed that PHAH caused enhanced hepatic and extrahepatic catabolism of intravenously administered 3 H-retinol-retinol binding protein-transthyretin as evidenced by increased inactive polar retinoids in liver, kidney, bile, and excreta. These polar retinoids were isolated from tissues and bile and are thought to represent oxidized and/or glucuronidated, elimination metabolites of vitamin A. PHAH increased the microsomal activity of cytochrome P-450 MFO and UDP-glucuronosyl transferase toward retinoic acid (RA), enzyme systems that are also known to be coordinately induced by PHAH. Increased serum and kidney vitamin A is likely a homeostatic response to PHAH-related increased target tissue catabolism. For serum, this was shown directly by the finding that PHAH caused decreased liver esterification of retinol recycled from the extrahepatic tissues and indirectly by the administration of the active target tissue metabolite, RA. After RA, both control and PHAH-treated rats lowered their serum vitamin A

Identification of GIG1, a GlcNAc-induced gene in Candida albicans needed for normal sensitivity to the chitin synthase inhibitor nikkomycin Z.

Science.gov (United States)

Gunasekera, Angelo; Alvarez, Francisco J; Douglas, Lois M; Wang, Hong X; Rosebrock, Adam P; Konopka, James B

2010-10-01

The amino sugar N-acetylglucosamine (GlcNAc) is known to be an important structural component of cells from bacteria to humans, but its roles in cell signaling are less well understood. GlcNAc induces two pathways in the human fungal pathogen Candida albicans. One activates cyclic AMP (cAMP) signaling, which stimulates the formation of hyphal cells and the expression of virulence genes, and the other pathway induces genes needed to catabolize GlcNAc. Microarray analysis of gene expression was carried out under four different conditions in order to characterize the transcriptional changes induced by GlcNAc. The most highly induced genes include those that encode a GlcNAc transporter (NGT1) and the GlcNAc catabolic enzymes (HXK1, DAC1, and NAG1). GlcNAc also activated most of the genes whose expression is increased when cells are triggered with other stimuli to form hyphae. Surprisingly, GlcNAc also induced a subset of genes that are regulated by galactose (GAL1, GAL7, and GAL10), which may be due to cross talk between signaling pathways. A novel GlcNAc-induced gene, GIG1, which is not essential for GlcNAc catabolism or the induction of hyphae, was identified. However, a Gig1-green fluorescent protein (GFP) fusion protein was specifically induced by GlcNAc, and not by other sugars. Gig1-GFP localized to the cytoplasm, where GlcNAc metabolism occurs. Significantly, a gig1Δ mutant displayed increased resistance to nikkomycin Z, which inhibits chitin synthase from converting UDP-GlcNAc into cell wall chitin. Gig1 is highly conserved in fungi, especially those that contain GlcNAc catabolic genes. These results implicate Gig1 in GlcNAc metabolism.

Synthesis of a posterior indicator protein in normal embryos and double abdomens of Smittia sp. (Chironomidae, Diptera).

Science.gov (United States)

Jäckle, H; Kalthoff, K

1980-01-01

In embryos of the chironomid midge Smittia, synthesis of a posterior indicator protein designated PI1 (Mr approximately 50,000; pI approximately 5.5) forecasts development of an abdomen as opposed to head and thorax. The protein is synthesized several hours before germ anlage formation. In normal embryos at early blastoderm stages, synthesis of PI1 is restricted to posterior embryonic fragments but not to pole cells. In "double-abdomen" embryos, a mirror-image duplication of the abdomen is formed by cells that would otherwise develop into head and thorax. Embryos were programmed for double-abdomen development by UV irradiation of the anterior pole, and half of them were reprogrammed for normal development by subsequent exposure to visible light (photoreversal). Correspondingly, PI1 was synthesized in anterior fragments of UV-irradiated embryos but not after photoreversal. In a control experiment, UV irradiation of the posterior pole caused neither double-abdomen formation nor PI1 synthesis in anterior fragments. The identity of PI1 formed in anterior fragments of prospective double abdomens with the protein found in posterior fragments was revealed by two-dimensional gel electrophoresis and limited proteolysis. Suppression of PI1 synthesis in anterior fragments of normal embryos is ascribed to the activity of cytoplasmic ribonucleoprotein particles thought to act as anterior determinants. Images PMID:6935679

Effects of Zinc Magnesium Aspartate (ZMA Supplementation on Training Adaptations and Markers of Anabolism and Catabolism

Directory of Open Access Journals (Sweden)

Almada Anthony

2004-12-01

Full Text Available Abstract This study examined whether supplementing the diet with a commercial supplement containing zinc magnesium aspartate (ZMA during training affects zinc and magnesium status, anabolic and catabolic hormone profiles, and/or training adaptations. Forty-two resistance trained males (27 ± 9 yrs; 178 ± 8 cm, 85 ± 15 kg, 18.6 ± 6% body fat were matched according to fat free mass and randomly assigned to ingest in a double blind manner either a dextrose placebo (P or ZMA 30–60 minutes prior to going to sleep during 8-weeks of standardized resistance-training. Subjects completed testing sessions at 0, 4, and 8 weeks that included body composition assessment as determined by dual energy X-ray absorptiometry, 1-RM and muscular endurance tests on the bench and leg press, a Wingate anaerobic power test, and blood analysis to assess anabolic/catabolic status as well as markers of health. Data were analyzed using repeated measures ANOVA. Results indicated that ZMA supplementation non-significantly increased serum zinc levels by 11 – 17% (p = 0.12. However, no significant differences were observed between groups in anabolic or catabolic hormone status, body composition, 1-RM bench press and leg press, upper or lower body muscular endurance, or cycling anaerobic capacity. Results indicate that ZMA supplementation during training does not appear to enhance training adaptations in resistance trained populations.

Lewis lung carcinoma regulation of mechanical stretch-induced protein synthesis in cultured myotubes.

Science.gov (United States)

Gao, Song; Carson, James A

2016-01-01

Mechanical stretch can activate muscle and myotube protein synthesis through mammalian target of rapamycin complex 1 (mTORC1) signaling. While it has been established that tumor-derived cachectic factors can induce myotube wasting, the effect of this catabolic environment on myotube mechanical signaling has not been determined. We investigated whether media containing cachectic factors derived from Lewis lung carcinoma (LLC) can regulate the stretch induction of myotube protein synthesis. C2C12 myotubes preincubated in control or LLC-derived media were chronically stretched. Protein synthesis regulation by anabolic and catabolic signaling was then examined. In the control condition, stretch increased mTORC1 activity and protein synthesis. The LLC treatment decreased basal mTORC1 activity and protein synthesis and attenuated the stretch induction of protein synthesis. LLC media increased STAT3 and AMP-activated protein kinase phosphorylation in myotubes, independent of stretch. Both stretch and LLC independently increased ERK1/2, p38, and NF-κB phosphorylation. In LLC-treated myotubes, the inhibition of ERK1/2 and p38 rescued the stretch induction of protein synthesis. Interestingly, either leukemia inhibitory factor or glycoprotein 130 antibody administration caused further inhibition of mTORC1 signaling and protein synthesis in stretched myotubes. AMP-activated protein kinase inhibition increased basal mTORC1 signaling activity and protein synthesis in LLC-treated myotubes, but did not restore the stretch induction of protein synthesis. These results demonstrate that LLC-derived cachectic factors can dissociate stretch-induced signaling from protein synthesis through ERK1/2 and p38 signaling, and that glycoprotein 130 signaling is associated with the basal stretch response in myotubes. Copyright © 2016 the American Physiological Society.

Phosphorylation of intracellular proteins related to the multihormonal regulation of prolactin: comparison of normal anterior pituitary cells in culture with the tumor-derived GH cell lines

International Nuclear Information System (INIS)

Beretta, L.; Boutterin, M.C.; Sobel, A.

1988-01-01

We have previously identified a group of cytoplasmic phosphoproteins (proteins 1-11) whose phosphorylation could be related, on a pharmacological basis, to the multihormonal regulation of PRL synthesis and release in the anterior pituitary tumor-derived GH cell lines. Phosphoproteins with identical migration properties on two-dimensional electrophoresis gels were also detectable in normal rat anterior pituitary cells in culture. We designed appropriate culture and [ 32 P] phosphate-labeling conditions allowing to analyze the regulation of the phosphorylation of these proteins in normal pituitary cells. TRH, 12-O-tetradecanoylphorbol-13-acetate, and vasoactive intestinal peptide induced the same qualitative changes in phosphorylation of proteins 1-11 in normal as in GH cells. Quantitative differences observed are most likely due to the heterogeneity of primary pituitary cultures. Phosphorylation changes affecting proteins 14-16, not previously detected in GH cells, were also observed with normal anterior pituitary cells. GH cell lines have lost the sensitivity of pituitary lactotrophs for dopamine, an important physiological inhibitor of PRL synthesis and release. In normal anterior pituitary cells in culture, dopamine inhibited also the TRH-stimulated phosphorylation of proteins 1-10, thus strengthening the correlation between phosphorylation of these proteins and multihormonal regulation of pituitary cell functions. Our results indicate: 1) that the same phosphoproteins as in GH cells are related to the multihormonal regulation of nontumoral, normal anterior pituitary cells in culture; 2) that dopamine acts by interfering with the phosphorylation of these proteins

Identification of GIG1, a GlcNAc-Induced Gene in Candida albicans Needed for Normal Sensitivity to the Chitin Synthase Inhibitor Nikkomycin Z▿§

Science.gov (United States)

Gunasekera, Angelo; Alvarez, Francisco J.; Douglas, Lois M.; Wang, Hong X.; Rosebrock, Adam P.; Konopka, James B.

2010-01-01

The amino sugar N-acetylglucosamine (GlcNAc) is known to be an important structural component of cells from bacteria to humans, but its roles in cell signaling are less well understood. GlcNAc induces two pathways in the human fungal pathogen Candida albicans. One activates cyclic AMP (cAMP) signaling, which stimulates the formation of hyphal cells and the expression of virulence genes, and the other pathway induces genes needed to catabolize GlcNAc. Microarray analysis of gene expression was carried out under four different conditions in order to characterize the transcriptional changes induced by GlcNAc. The most highly induced genes include those that encode a GlcNAc transporter (NGT1) and the GlcNAc catabolic enzymes (HXK1, DAC1, and NAG1). GlcNAc also activated most of the genes whose expression is increased when cells are triggered with other stimuli to form hyphae. Surprisingly, GlcNAc also induced a subset of genes that are regulated by galactose (GAL1, GAL7, and GAL10), which may be due to cross talk between signaling pathways. A novel GlcNAc-induced gene, GIG1, which is not essential for GlcNAc catabolism or the induction of hyphae, was identified. However, a Gig1-green fluorescent protein (GFP) fusion protein was specifically induced by GlcNAc, and not by other sugars. Gig1-GFP localized to the cytoplasm, where GlcNAc metabolism occurs. Significantly, a gig1Δ mutant displayed increased resistance to nikkomycin Z, which inhibits chitin synthase from converting UDP-GlcNAc into cell wall chitin. Gig1 is highly conserved in fungi, especially those that contain GlcNAc catabolic genes. These results implicate Gig1 in GlcNAc metabolism. PMID:20675577

Radioimmunoassay of alpha-foeto protein in the amniotic fluid in normal and pathological pregnancies

International Nuclear Information System (INIS)

Degueldre, M.; Golstein, J.; Rodesch, F.; L'Hermite, M.

1975-01-01

A radioimmunoassay of AFP was developed and the normal amniotic concentrations of this protein were measured as a function of the gestation age. The specific reagents used included a rabbit anti-AFP serum and a highly purified preparation of AFP labelled with 125 I, which also served as a standard. Amniotic fluid was drawn off by amniocentesis between the 11th and 40th week following the last menstrual period. Samples of amniotic fluid were also obtained in 2 cases of foetal death in utero and 3 cases of anencephaly. The normal amniotic AFP concentration limits were particularly well established between the 14th and 18th weeks, an ideal period to perform an amniocentesis both from a technical viewpoint and with regard to the bulk of information obtainable for the antenatal diagnosis of many congenital diseases. The concentrations observed in pathological cases were distinctly higher than the upper 95% confidence limit of normal values for the gestation age considered [fr

Association between uncoupling protein 2, adiponectin and resting energy expenditure in obese women with normal and low resting energy expenditure.

Science.gov (United States)

Taghadomi Masoumi, Zahra; Eshraghian, Mohammad Reza; Hedayati, Mahdi; Pishva, Hamideh

2018-02-01

Obesity is recognized as the most prevalent metabolic disease worldwide. Decreases in energy expenditure may increase risk of obesity. One of the key regulators of energy balance is uncoupling protein2 (UCP2), a transporter protein presents in mitochondrial inner membrane. Moreover, adiponectin is the most abundant adipocytokine, it may play a role in energy metabolism and gene expression of UCP2. The aim of this study was to investigate potential associations between the level of uncoupling protein 2 and adiponectin and their relationship with REE (Resting Energy Expenditure) in obese women with normal and low resting energy expenditure. A total of 49 subjects (women, 25-50 years old), were included in current study, 16 subjects with BMI > 30 and low resting energy expenditure, 17 subjects with BMI > 30 and normal resting energy expenditure and 16 non-obese subjects as a control group. Anthropometric, body composition parameters and resting energy expenditure were measured. Plasma adiponectin, UCP2 protein and total protein in PBMC were determined. Measured resting energy expenditure in obese subjects with low REE was significantly lower than other groups. Plasma adiponectin in the obese subjects with low REE was significantly lower compared to normal weight group. There was a significant relationship between 'UCP2 protein/Total protein' ratio and plasma adiponectin in obese group with low REE and in three groups when we pooled. There was a significant association between REE and plasma adiponectin in three groups when we pooled. There was a significant association between plasma adiponectin and REE. Moreover, there was a significant relationship between UCP2 and REE.

The Effect of Oral Leucine on Protein Metabolism in Adolescents with Type 1 Diabetes Mellitus

OpenAIRE

Vardhini Desikan; Izolda Mileva; Jeremy Garlick; Andrew H. Lane; Thomas A. Wilson; Margaret A. McNurlan

2010-01-01

Lack of insulin results in a catabolic state in subjects with insulin-dependent diabetes mellitus which is reversed by insulin treatment. Amino acid supply, especially branched chain amino acids such as leucine, enhances protein synthesis in both animal and human studies. This small study was undertaken to assess the acute effect of supplemental leucine on protein metabolism in adolescents with type 1 diabetes. L-[1-13C] Leucine was used to assess whole-body protein metabolism in six adolesc...

Regulatory mechanisms of skeletal muscle protein turnover during exercise

DEFF Research Database (Denmark)

Rose, Adam John; Richter, Erik

2009-01-01

Skeletal muscle protein turnover is a relatively slow metabolic process that is altered by various physiological stimuli such as feeding/fasting and exercise. During exercise, catabolism of amino acids contributes very little to ATP turnover in working muscle. With regards to protein turnover......, there is now consistent data from tracer studies in rodents and humans showing that global protein synthesis is blunted in working skeletal muscle. Whether there is altered skeletal muscle protein breakdown during exercise remains unclear. The blunting of protein synthesis is believed to be mediated...... downstream of changes in intracellular Ca(2+) and energy turnover. In particular, a signaling cascade involving Ca(2+)-calmodulin-eEF2 kinase-eEF2 is implicated. The possible functional significance of altered protein turnover in working skeletal muscle during exercise is discussed. Further work...

Shell extracts of the edible mussel and oyster induce an enhancement of the catabolic pathway of human skin fibroblasts, in vitro.

Science.gov (United States)

Latire, Thomas; Legendre, Florence; Bouyoucef, Mouloud; Marin, Frédéric; Carreiras, Franck; Rigot-Jolivet, Muriel; Lebel, Jean-Marc; Galéra, Philippe; Serpentini, Antoine

2017-10-01

Mollusc shells are composed of more than 95% calcium carbonate and less than 5% organic matrix consisting mostly of proteins, glycoproteins and polysaccharides. In this study, we investigated the effects of matrix macromolecular components extracted from the shells of two edible molluscs of economic interest, i.e., the blue mussel Mytilus edulis and the Pacific oyster Crassostrea gigas. The potential biological activities of these organic molecules were analysed on human dermal fibroblasts in primary culture. Our results demonstrate that shell extracts of the two studied molluscs modulate the metabolic activities of the cells. In addition, the extracts caused a decrease of type I collagen and a concomitant increase of active MMP-1, both at the mRNA and the protein levels. Therefore, our results suggest that shell extracts from M. edulis and C. gigas contain molecules that promote the catabolic pathway of human dermal fibroblasts. This work emphasises the potential use of these shell matrices in the context of anti-fibrotic strategies, particularly against scleroderma. More generally, it stresses the usefulness to valorise bivalve shells that are coproducts of shellfish farming activity.

The mechanisms of haem catabolism

International Nuclear Information System (INIS)

Brown, S.B.; King, R.F.G.J.

1978-01-01

The pathway of haem breakdown in living rats was studied by using 18 0 in the oxygen that the animals consumed. By cannulation of the common bile duct and collection of bile, labelled bilirubin was isolated and its mass spectrum determined. One set of results was obtained for a rat to which haemoglobin had been intravenously administered and another set obtained for a rat that was not given exogenous haem. Isomerization of bilirubin IXα to the XIIIα and IIIα isomers did not occur to any significant extent. The 18 O-labelling pattern obtained in the bilirubin was consistent with a Two-Molecule Mechanism, whereby the terminal lactam oxygen atoms of bilirubin are derived from different oxygen molecules. The consequences of this mechanism are discussed in terms of the possible intermediates of the catabolic pathway. 18 0-labelled bilirubin appeared in the bile in less than 10 min after exposure of the animals to labelled oxygen. This result suggests that all of the chemical transformations involving production of biliverdin, reduction to bilirubin and conjugation of the bilirubin are fast processes. The quantitative recovery of label obtained in the experiments suggests that there is little or no exchange of newly synthesized bilirubin with existing bilirubin pools in the animal. (author)

Effect of whey protein and a free amino acid mixture simulating whey protein on measures of satiety in normal-weight women.

Science.gov (United States)

Chungchunlam, Sylvia M S; Henare, Sharon J; Ganesh, Siva; Moughan, Paul J

2016-11-01

Dietary protein is considered more satiating than carbohydrate, and whey protein is more satiating than other protein sources. The purported satiating effect of whey protein may be due to direct effects of the unique mixture of proteins in whey, due to the effects of peptides released upon digestion and/or its amino acid composition. The objective of the present study was to compare the satiating effects of intact whey protein isolate (WPI) or a free amino acid mixture (AAM) simulating the amino acid composition of the WPI. A single-blind completely randomised block design included twenty, healthy, adult women (age 24·2 (sem 0·8) years) of normal weight (BMI 22·7 (sem 0·4) kg/m2). Following consumption of isoenergetic (approximately 1800 kJ) preload meals enriched (52 g amino acid equivalent) with WPI or AAM, consumption of an ad libitum test meal 120 min later and subjective feelings of appetite using visual analogue scales (VAS) were determined. There were no significant differences (P=0·24) in the ad libitum test meal intakes between the WPI (268·5 (sem 27·3) g) and the AAM (238·4 (sem 22·7) g) preload meals. Subjective VAS ratings of appetite did not differ significantly between the WPI and the AAM preload meals (P>0·05). Intact whey protein and a free AAM simulating the whey protein showed similar effects on satiety. This suggests that the satiating effect of whey protein may be related to its specific amino acid composition.

Mutations Enhancing Amino Acid Catabolism Confer a Growth Advantage in Stationary Phase

Science.gov (United States)

Zinser, Erik R.; Kolter, Roberto

1999-01-01

Starved cultures of Escherichia coli undergo successive rounds of population takeovers by mutants of increasing fitness. These mutants express the growth advantage in stationary phase (GASP) phenotype. Previous work identified the rpoS819 allele as a GASP mutation allowing cells to take over stationary-phase cultures after growth in rich media (M. M. Zambrano, D. A. Siegele, M. A. Almirón, A. Tormo, and R. Kolter, Science 259:1757–1760, 1993). Here we have identified three new GASP loci from an aged rpoS819 strain: sgaA, sgaB, and sgaC. Each locus is capable of conferring GASP on the rpoS819 parent, and they can provide successively higher fitnesses for the bacteria in the starved cultures. All four GASP mutations isolated thus far allow for faster growth on both individual and mixtures of amino acids. Each mutation confers a growth advantage on a different subset of amino acids, and these mutations act in concert to increase the overall catabolic capacity of the cell. We present a model whereby this enhanced ability to catabolize amino acids is responsible for the fitness gain during carbon starvation, as it may allow GASP mutants to outcompete the parental cells when growing on the amino acids released by dying cells. PMID:10482523

The steroid catabolic pathway of the intracellular pathogen Rhodococcus equi is important for pathogenesis and a target for vaccine development.

Directory of Open Access Journals (Sweden)

R van der Geize

2011-08-01

Full Text Available Rhodococcus equi causes fatal pyogranulomatous pneumonia in foals and immunocompromised animals and humans. Despite its importance, there is currently no effective vaccine against the disease. The actinobacteria R. equi and the human pathogen Mycobacterium tuberculosis are related, and both cause pulmonary diseases. Recently, we have shown that essential steps in the cholesterol catabolic pathway are involved in the pathogenicity of M. tuberculosis. Bioinformatic analysis revealed the presence of a similar cholesterol catabolic gene cluster in R. equi. Orthologs of predicted M. tuberculosis virulence genes located within this cluster, i.e. ipdA (rv3551, ipdB (rv3552, fadA6 and fadE30, were identified in R. equi RE1 and inactivated. The ipdA and ipdB genes of R. equi RE1 appear to constitute the α-subunit and β-subunit, respectively, of a heterodimeric coenzyme A transferase. Mutant strains RE1ΔipdAB and RE1ΔfadE30, but not RE1ΔfadA6, were impaired in growth on the steroid catabolic pathway intermediates 4-androstene-3,17-dione (AD and 3aα-H-4α(3'-propionic acid-5α-hydroxy-7aβ-methylhexahydro-1-indanone (5α-hydroxy-methylhexahydro-1-indanone propionate; 5OH-HIP. Interestingly, RE1ΔipdAB and RE1ΔfadE30, but not RE1ΔfadA6, also displayed an attenuated phenotype in a macrophage infection assay. Gene products important for growth on 5OH-HIP, as part of the steroid catabolic pathway, thus appear to act as factors involved in the pathogenicity of R. equi. Challenge experiments showed that RE1ΔipdAB could be safely administered intratracheally to 2 to 5 week-old foals and oral immunization of foals even elicited a substantial protective immunity against a virulent R. equi strain. Our data show that genes involved in steroid catabolism are promising targets for the development of a live-attenuated vaccine against R. equi infections.

Insulin signaling regulates fatty acid catabolism at the level of CoA activation.

Directory of Open Access Journals (Sweden)

Xiaojun Xu

2012-01-01

Full Text Available The insulin/IGF signaling pathway is a highly conserved regulator of metabolism in flies and mammals, regulating multiple physiological functions including lipid metabolism. Although insulin signaling is known to regulate the activity of a number of enzymes in metabolic pathways, a comprehensive understanding of how the insulin signaling pathway regulates metabolic pathways is still lacking. Accepted knowledge suggests the key regulated step in triglyceride (TAG catabolism is the release of fatty acids from TAG via the action of lipases. We show here that an additional, important regulated step is the activation of fatty acids for beta-oxidation via Acyl Co-A synthetases (ACS. We identify pudgy as an ACS that is transcriptionally regulated by direct FOXO action in Drosophila. Increasing or reducing pudgy expression in vivo causes a decrease or increase in organismal TAG levels respectively, indicating that pudgy expression levels are important for proper lipid homeostasis. We show that multiple ACSs are also transcriptionally regulated by insulin signaling in mammalian cells. In sum, we identify fatty acid activation onto CoA as an important, regulated step in triglyceride catabolism, and we identify a mechanistic link through which insulin regulates lipid homeostasis.

The effect of CreA in glucose and xylose catabolism in Aspergillus nidulans

DEFF Research Database (Denmark)

Prathumpai, Wai; Mcintyre, Mhairi; Nielsen, Jens

2004-01-01

The catabolism of glucose and xylose was studied in a wild type and creA deleted (carbon catabolite de-repressed) strain of Aspergillus nidulans. Both strains were cultivated in bioreactors with either glucose or xylose as the sole carbon source, or in the presence of both sugars. In the cultivat......The catabolism of glucose and xylose was studied in a wild type and creA deleted (carbon catabolite de-repressed) strain of Aspergillus nidulans. Both strains were cultivated in bioreactors with either glucose or xylose as the sole carbon source, or in the presence of both sugars...... on the sugar mixture, glucose repression of xylose utilisation was observed; with xylose utilisation occurring only after glucose was depleted. This phenomenon was not seen in the creA deleted strain, where glucose and xylose were catabolised simultaneously. Measurement of key metabolites and the activities...... of key enzymes in the xylose utilisation pathway revealed that xylose metabolism was occurring in the creA deleted strain, even at high glucose concentrations. Conversely, in the wild type strain, activities of the key enzymes for xylose metabolism increased only when the effects of glucose repression...

Engineering a synthetic anaerobic respiration for reduction of xylose to xylitol using NADH output of glucose catabolism by Escherichia coli AI21.

Science.gov (United States)

Iverson, Andrew; Garza, Erin; Manow, Ryan; Wang, Jinhua; Gao, Yuanyuan; Grayburn, Scott; Zhou, Shengde

2016-04-16

Anaerobic rather than aerobic fermentation is preferred for conversion of biomass derived sugars to high value redox-neutral and reduced commodities. This will likely result in a higher yield of substrate to product conversion and decrease production cost since substrate often accounts for a significant portion of the overall cost. To this goal, metabolic pathway engineering has been used to optimize substrate carbon flow to target products. This approach works well for the production of redox neutral products such as lactic acid from redox neutral sugars using the reducing power NADH (nicotinamide adenine dinucleotide, reduced) generated from glycolysis (2 NADH per glucose equivalent). Nevertheless, greater than two NADH per glucose catabolized is needed for the production of reduced products (such as xylitol) from redox neutral sugars by anaerobic fermentation. The Escherichia coli strain AI05 (ΔfrdBC ΔldhA ΔackA Δ(focA-pflB) ΔadhE ΔptsG ΔpdhR::pflBp 6-(aceEF-lpd)), previously engineered for reduction of xylose to xylitol using reducing power (NADH equivalent) of glucose catabolism, was further engineered by 1) deleting xylAB operon (encoding for xylose isomerase and xylulokinase) to prevent xylose from entering the pentose phosphate pathway; 2) anaerobically expressing the sdhCDAB-sucABCD operon (encoding for succinate dehydrogenase, α-ketoglutarate dehydrogenase and succinyl-CoA synthetase) to enable an anaerobically functional tricarboxcylic acid cycle with a theoretical 10 NAD(P)H equivalent per glucose catabolized. These reducing equivalents can be oxidized by synthetic respiration via xylose reduction, producing xylitol. The resulting strain, AI21 (pAI02), achieved a 96 % xylose to xylitol conversion, with a yield of 6 xylitol per glucose catabolized (molar yield of xylitol per glucose consumed (YRPG) = 6). This represents a 33 % improvement in xylose to xylitol conversion, and a 63 % increase in xylitol yield per glucose catabolized over

ARA1 regulates not only l-arabinose but also d-galactose catabolism in Trichoderma reesei

NARCIS (Netherlands)

Benocci, Tiziano; Aguilar-Pontes, Maria Victoria; Kun, Roland Sándor; Seiboth, Bernhard; de Vries, Ronald P; Daly, Paul

2017-01-01

Trichoderma reesei is used to produce saccharifying enzyme cocktails for biofuels. There is limited understanding of the transcription factors (TFs) that regulate genes involved in release and catabolism of l-arabinose and d-galactose, as the main TF XYR1 is only partially involved. Here, the T.

Haloacetate analogs of pheromones: Effects on catabolism and electrophysiology inPlutella xylostella.

Science.gov (United States)

Prestwich, G D; Streinz, L

1988-03-01

A series of mono-, di-, and trihalogenated acetate analogs of Zl 1-16: Ac were prepared and examined for electrophysiological activity in antennae of males of the diamondback moth,Plutella xylostella. In addition, two potential affinity labels, a diazoacetate (Dza) and a trifluoromethyl ketone (Tfp), were evaluated for EAG activity. The Z11-16∶Ac showed the highest activity in EAG assays, followed by the fluorinated acetates, but other halo-acetates were essentially inactive. The polar diazoacetate and the trifluoromethyl ketone were also very weak EAG stimulants. The effects of these analogs on the hydrolysis of [(3)H]Z11-16∶Ac to [(3)H]Z11-16∶OH by antennal esterases was also examined. The three fluorinated acetates showed the greatest activity as inhibitors in competition assays, with rank order F2Ac > F(3)Ac > FAc > Ac > Cl2Ac > ClAc > Dza > Br2Ac > BrAc > Tfp > I > Cl3Ac > Br3Ac > OH. The relative polarities of the haloacetates, as determined by TLC mobility, are in the order mono- > di- > trihalo, but F, Cl, Br, and I all confer similar polarities within a substitution group. Thus, the steric size appears to be the predominant parameter affecting the interactions of the haloacetate analogs with both receptor and catabolic proteins inP. xylostella males.

The abundant marine bacterium Pelagibacter simultaneously catabolizes dimethylsulfoniopropionate to the gases dimethyl sulfide and methanethiol

Energy Technology Data Exchange (ETDEWEB)

Sun, Jing; Todd, Jonathan D.; Thrash, J. Cameron; Qian, Yanping; Qian, Michael C.; Temperton, Ben; Guo, Jiazhen; Fowler, Emily K.; Aldrich, Joshua T.; Nicora, Carrie D.; Lipton, Mary S.; Smith, Richard D.; De Leenheer, Patrick; Payne, Samuel H.; Johnston, Andrew W. B.; Davie-Martin, Cleo L.; Halsey, Kimberly H.; Giovannoni, Stephen J.

2016-05-16

Marine phytoplankton produce ~109 tons of dimethylsulfoniopropionate (DMSP) per year1,2, an estimated 10% of which is catabolized by bacteria through the DMSP cleavage pathway to the climatically active gas dimethyl sulfide (DMS)3,4. SAR11 Alphaproteobacteria (order Pelagibacterales), the most abundant chemoorganotrophic bacteria in the oceans, have been shown to assimilate DMSP into biomass, thereby supplying this cell’s unusual requirement for reduced sulfur5,6. Here we report that Pelagibacter HTCC1062 produces the gas methanethiol (MeSH) and that simultaneously a second DMSP catabolic pathway, mediated by a DMSP lyase, shunts as much as 59% of DMSP uptake to DMS production. We propose a model in which the allocation of DMSP between these pathways is kinetically controlled to release increasing amounts of DMS as the supply of DMSP exceeds cellular sulfur demands for biosynthesis. These findings suggest that DMSP supply and demand relationships in Pelagibacter metabolism are important to determining rates of oceanic DMS production.

Catabolism of lysine by mixed rumen bacteria

International Nuclear Information System (INIS)

Onodera, Ryoji; Kandatsu, Makoto.

1975-01-01

Metabolites arising from the catabolism of lysine by the mixed rumen bacteria were chromatographically examined by using radioactive lysine. After 6 hr incubation, 241 nmole/ml of lysine was decomposed to give ether-soluble substances and CO 2 by the bacteria and 90 nmole/ml of lysine was incorporated unchanged into the bacteria. delta-Aminovalerate, cadaverine or pipecolate did not seem to be produced from lysine even after incubation of the bacteria with addition of those three amino compounds to trap besides lysine and radioactive lysine. Most of the ether-soluble substances produced from radioactive lysine was volatile fatty acids (VFAs). Fractionation of VFAs revealed that the peaks of butyric and acetic acids coincided with the strong radioactive peaks. Small amounts of radioactivities were detected in propionic acid peak and a peak assumed to be caproic acid. The rumen bacteria appeared to decompose much larger amounts of lysine than the rumen ciliate protozoa did. (auth.)

l-Glucitol Catabolism in Stenotrophomonas maltophilia Ac

Science.gov (United States)

Brechtel, Elke; Huwig, Alexander; Giffhorn, Friedrich

2002-01-01

The carbohydrate catabolism of the bacterium Stenotrophomonas maltophilia Ac (previously named Pseudomonas sp. strain Ac), which is known to convert the unnatural polyol l-glucitol to d-sorbose during growth on the former as the sole source of carbon and energy, was studied in detail. All enzymes operating in a pathway that channels l-glucitol via d-sorbose into compounds of the intermediary metabolism were demonstrated, and for some prominent reactions the products of conversion were identified. d-Sorbose was converted by C-3 epimerization to d-tagatose, which, in turn, was isomerized to d-galactose. d-Galactose was the initial substrate of the De Ley-Doudoroff pathway, involving reactions of NAD-dependent oxidation of d-galactose to d-galactonate, its dehydration to 2-keto-3-deoxy-d-galactonate, and its phosphorylation to 2-keto-3-deoxy-d-galactonate 6-phosphate. Finally, aldol cleavage yielded pyruvate and d-glycerate 3-phosphate as the central metabolic intermediates. PMID:11823194

A mass spectrometric method to determine activities of enzymes involved in polyamine catabolism

International Nuclear Information System (INIS)

Moriya, Shunsuke; Iwasaki, Kaori; Samejima, Keijiro; Takao, Koichi; Kohda, Kohfuku; Hiramatsu, Kyoko; Kawakita, Masao

2012-01-01

Highlights: ► Compounds in polyamine catabolic pathway were determined by a column-free ESI-TOF MS. ► N 1 - and N 8 -acetylspermidine were determined by a column-free ESI-MS/MS. ► The method was applied to determine activities of APAO, SMO, and SSAT in the pathway. ► The assay method contained stable isotope-labeled natural substrates. ► It is applicable to biological samples containing natural substrate and product. - Abstract: An analytical method for the determination of three polyamines (putrescine, spermidine, and spermine) and five acetylpolyamines [N 1 -acetylspermidine (N 1 AcSpd), N 8 -acetylspermidine (N 8 AcSpd), N 1 -acetylspermine, N 1 ,N 8 -diacetylspermidine, and N 1 ,N 12 -diacetylspermine] involved in the polyamine catabolic pathway has been developed using a hybrid tandem mass spectrometer. Heptafluorobutyryl (HFB) derivatives of these compounds and respective internal standards labeled with stable isotopes were analyzed simultaneously by TOF MS, based on peak areas appearing at appropriate m/z values. The isomers, N 1 AcSpd and N 8 AcSpd were determined from their fragment ions, the acetylamidopropyl and acetylamidobutyl groups, respectively, using MS/MS with 13 C 2 -N 1 AcSpd and 13 C 2 -N 8 AcSpd which have the 13 C 2 -acetyl group as an internal standard. The TOF MS method was successfully applied to measure the activity of enzymes involved in polyamine catabolic pathways, namely N 1 -acetylpolyamine oxidase (APAO), spermine oxidase (SMO), and spermidine/spermine N 1 -acetyltransferase (SSAT). The following natural substrates and products labeled with stable isotopes considering the application to biological samples were identified; for APAO, [4,9,12- 15 N 3 ]-N 1 -acetylspermine and [1,4,8- 15 N 3 ]spermidine ( 15 N 3 -Spd), respectively; for SMO, [1,4,8,12- 15 N 4 ]spermine and 15 N 3 -Spd, respectively; and for SSAT, 15 N 3 -Spd and [1,4,8- 15 N 3 ]-N 1 -acetylspermidine, respectively.

pGenN, a Gene Normalization Tool for Plant Genes and Proteins in Scientific Literature

Science.gov (United States)

Ding, Ruoyao; Arighi, Cecilia N.; Lee, Jung-Youn; Wu, Cathy H.; Vijay-Shanker, K.

2015-01-01

Background Automatically detecting gene/protein names in the literature and connecting them to databases records, also known as gene normalization, provides a means to structure the information buried in free-text literature. Gene normalization is critical for improving the coverage of annotation in the databases, and is an essential component of many text mining systems and database curation pipelines. Methods In this manuscript, we describe a gene normalization system specifically tailored for plant species, called pGenN (pivot-based Gene Normalization). The system consists of three steps: dictionary-based gene mention detection, species assignment, and intra species normalization. We have developed new heuristics to improve each of these phases. Results We evaluated the performance of pGenN on an in-house expertly annotated corpus consisting of 104 plant relevant abstracts. Our system achieved an F-value of 88.9% (Precision 90.9% and Recall 87.2%) on this corpus, outperforming state-of-art systems presented in BioCreative III. We have processed over 440,000 plant-related Medline abstracts using pGenN. The gene normalization results are stored in a local database for direct query from the pGenN web interface (proteininformationresource.org/pgenn/). The annotated literature corpus is also publicly available through the PIR text mining portal (proteininformationresource.org/iprolink/). PMID:26258475

Protein and energy intake in advanced chronic kidney disease: how much is too much?

Science.gov (United States)

Ikizler, T Alp

2007-01-01

Uremic wasting is strongly associated with increased risk of death and hospitalization events in patients with advanced chronic kidney disease (CKD). Recent evidence indicates that patients with advanced chronic kidney disease are prone to uremic wasting due to several factors, which include the dialysis procedure and certain comorbid conditions, especially chronic inflammation and insulin resistance or deficiency. While the catabolic effects of dialysis can be readily avoided with intradialytic nutritional supplementation, there are no established alternative strategies to avoid the catabolic consequences of comorbid conditions other than treatment of their primary etiology. To this end, there is no indication that simply increasing dietary protein and energy intake above the required levels based on level of kidney disease is beneficial in patients with advanced chronic kidney disease. However, aside from the potential adverse effects such as uremic toxin production, dietary protein and energy intake in excess of actual needs might be beneficial in maintenance dialysis patients as it may lead to weight gain over time. Clearly, the role of obesity in advanced uremia needs to be examined in detail prior to making any clinically applicable recommendations, both in terms of ''low'' and ''high'' dietary protein and energy intake.

Establishing the proteome of normal human cerebrospinal fluid.

Directory of Open Access Journals (Sweden)

Steven E Schutzer

2010-06-01

Full Text Available Knowledge of the entire protein content, the proteome, of normal human cerebrospinal fluid (CSF would enable insights into neurologic and psychiatric disorders. Until now technologic hurdles and access to true normal samples hindered attaining this goal.We applied immunoaffinity separation and high sensitivity and resolution liquid chromatography-mass spectrometry to examine CSF from healthy normal individuals. 2630 proteins in CSF from normal subjects were identified, of which 56% were CSF-specific, not found in the much larger set of 3654 proteins we have identified in plasma. We also examined CSF from groups of subjects previously examined by others as surrogates for normals where neurologic symptoms warranted a lumbar puncture but where clinical laboratory were reported as normal. We found statistically significant differences between their CSF proteins and our non-neurological normals. We also examined CSF from 10 volunteer subjects who had lumbar punctures at least 4 weeks apart and found that there was little variability in CSF proteins in an individual as compared to subject to subject.Our results represent the most comprehensive characterization of true normal CSF to date. This normal CSF proteome establishes a comparative standard and basis for investigations into a variety of diseases with neurological and psychiatric features.

High proportions of older people with normal nutritional status have poor protein intake and low diet quality.

Science.gov (United States)

Jyväkorpi, S K; Pitkälä, K H; Puranen, T M; Björkman, M P; Kautiainen, H; Strandberg, T E; Soini, H H; Suominen, M H

2016-01-01

The Mini Nutritional Assessment (MNA) is a well-validated instrument examining the nutritional status of older people. The aim of this study was to examine how older people's energy and nutrient intakes are associated with the MNA and to determine how sensitive and specific MNA is in identifying those having low energy and protein intakes. This cross-sectional study combined data from five nutritional studies (N=900): both home-dwelling and institutionalized older people without and with disabilities. Their nutritional status was assessed with MNA, and nutrient intakes were retrieved from 1 to 3day food diaries. Nutrient intakes were divided according to MNA status (normal nutritional status, at-risk of malnutrition, malnourished). Sensitivity, specificity, and likelihood ratios of MNA of various cut-off points were tested with recommended protein and energy intakes. ROC curves was constructed. Energy, protein and most nutrient intakes showed logical linear trends according to MNA classes. However, more than three-fourths of the participants with MNA>23.5 had lower than recommended protein intakes. Sensitivity of MNA ranged from 0.32 to 0.82 for recommended energy (F:1570kcal/d/M:2070kcal/d) and protein intakes (1.0g/kg BW or 1.2g/kgBW) cut-off points, and specificity from 0.75 to 0.25, respectively. AUC values were low (0.52-0.53). MNA status was consistently associated with nutrient intakes and diet quality. However, a high proportion of older people even with normal nutritional status had poor energy and protein intakes. Thus, MNA does not identify all those with poor nutrient intakes who may be at risk of developing malnutrition. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Perturbation of polyamine catabolism affects grape ripening of Vitis vinifera cv. Trincadeira.

Science.gov (United States)

Agudelo-Romero, Patricia; Ali, Kashif; Choi, Young H; Sousa, Lisete; Verpoorte, Rob; Tiburcio, Antonio F; Fortes, Ana M

2014-01-01

Grapes are economically the most important fruit worldwide. However, the complexity of biological events that lead to ripening of nonclimacteric fruits is not fully understood, particularly the role of polyamines' catabolism. The transcriptional and metabolic profilings complemented with biochemical data were studied during ripening of Trincadeira grapes submitted to guazatine treatment, a potent inhibitor of polyamine oxidase activity. The mRNA expression profiles of one time point (EL 38) corresponding to harvest stage was compared between mock and guazatine treatments using Affymetrix GrapeGen(®) genome array. A total of 2113 probesets (1880 unigenes) were differentially expressed between these samples. Quantitative RT-PCR validated microarrays results being carried out for EL 35 (véraison berries), EL 36 (ripe berries) and EL 38 (harvest stage berries). Metabolic profiling using HPLC and (1)H NMR spectroscopy showed increase of putrescine, proline, threonine and 1-O-ethyl-β-glucoside in guazatine treated samples. Genes involved in amino acid, carbohydrate and water transport were down-regulated in guazatine treated samples suggesting that the strong dehydrated phenotype obtained in guazatine treated samples may be due to impaired transport mechanisms. Genes involved in terpenes' metabolism were differentially expressed between guazatine and mock treated samples. Altogether, results support an important role of polyamine catabolism in grape ripening namely in cell expansion and aroma development. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

CLONING AND CHARACTERIZATION OF THE PHTHALATE CATABOLISM REGION OF PRE1 OF ARTHROBACTER KEYSERI 12B

Science.gov (United States)

o-Phthalate (benzene-1,2-dicarboxylate) is a central intermediate in the bacterial degradation of phthalate ester plasticizers as well as of a number of fused-ring polycyclic aromatic hydrocarbons found in fossil fuels. In Arthrobacter keyseri 12B, the genes encoding catabolism o...

Changes in energy expenditure associated with ingestion of high protein, high fat versus high protein, low fat meals among underweight, normal weight, and overweight females

Directory of Open Access Journals (Sweden)

White Barry D

2007-11-01

Full Text Available Abstract Background Metabolic rate is known to rise above basal levels after eating, especially following protein consumption. Yet, this postprandial rise in metabolism appears to vary among individuals. This study examined changes in energy expenditure in response to ingestion of a high protein, high fat (HPHF meal versus an isocaloric high protein, low fat (HPLF meal in underweight, normal weight, or overweight females (n = 21 aged 19–28 years. Methods Energy expenditure, measured using indirect calorimetry, was assessed before and every 30 minutes for 3.5 hours following consumption of the meals on two separate occasions. Height and weight were measured using standard techniques. Body composition was measured using bioelectrical impedance analysis. Results Significant positive correlations were found between body mass index (BMI and baseline metabolic rate (MR (r = 0.539; p = 0.017, between body weight and baseline MR (r = 0.567; p = 0.011, between BMI and average total change in MR (r = 0.591; p = 0.008, and between body weight and average total change in MR (r = 0.464; p = 0.045. Metabolic rate (kcal/min was significantly higher in the overweight group than the normal weight group, which was significantly higher than the underweight group across all times and treatments. However, when metabolic rate was expressed per kg fat free mass (ffm, no significant difference was found in postprandial energy expenditure between the overweight and normal groups. Changes in MR (kcal/min and kcal/min/kg ffm from the baseline rate did not significantly differ in the underweight (n = 3 or in the overweight subjects (n = 5 following consumption of either meal at any time. Changes in MR (kcal/min and kcal/min/kg ffm from baseline were significantly higher in normal weight subjects (n = 11 across all times following consumption of the HPHF meal versus the HPLF meal. Conclusion There is no diet-induced thermogenic advantage between the HPHF and HPLF meals in

Regulation of adipose branched-chain amino acid catabolism enzyme expression and cross-adipose amino acid flux in human obesity

Science.gov (United States)

Lackey, Denise E.; Lynch, Christopher J.; Olson, Kristine C.; Mostaedi, Rouzbeh; Ali, Mohamed; Smith, William H.; Karpe, Fredrik; Humphreys, Sandy; Bedinger, Daniel H.; Dunn, Tamara N.; Thomas, Anthony P.; Oort, Pieter J.; Kieffer, Dorothy A.; Amin, Rajesh; Bettaieb, Ahmed; Haj, Fawaz G.; Permana, Paska; Anthony, Tracy G.

2013-01-01

Elevated blood branched-chain amino acids (BCAA) are often associated with insulin resistance and type 2 diabetes, which might result from a reduced cellular utilization and/or incomplete BCAA oxidation. White adipose tissue (WAT) has become appreciated as a potential player in whole body BCAA metabolism. We tested if expression of the mitochondrial BCAA oxidation checkpoint, branched-chain α-ketoacid dehydrogenase (BCKD) complex, is reduced in obese WAT and regulated by metabolic signals. WAT BCKD protein (E1α subunit) was significantly reduced by 35–50% in various obesity models (fa/fa rats, db/db mice, diet-induced obese mice), and BCKD component transcripts significantly lower in subcutaneous (SC) adipocytes from obese vs. lean Pima Indians. Treatment of 3T3-L1 adipocytes or mice with peroxisome proliferator-activated receptor-γ agonists increased WAT BCAA catabolism enzyme mRNAs, whereas the nonmetabolizable glucose analog 2-deoxy-d-glucose had the opposite effect. The results support the hypothesis that suboptimal insulin action and/or perturbed metabolic signals in WAT, as would be seen with insulin resistance/type 2 diabetes, could impair WAT BCAA utilization. However, cross-tissue flux studies comparing lean vs. insulin-sensitive or insulin-resistant obese subjects revealed an unexpected negligible uptake of BCAA from human abdominal SC WAT. This suggests that SC WAT may not be an important contributor to blood BCAA phenotypes associated with insulin resistance in the overnight-fasted state. mRNA abundances for BCAA catabolic enzymes were markedly reduced in omental (but not SC) WAT of obese persons with metabolic syndrome compared with weight-matched healthy obese subjects, raising the possibility that visceral WAT contributes to the BCAA metabolic phenotype of metabolically compromised individuals. PMID:23512805

Ethylene-enhanced catabolism of [14C]indole-3-acetic acid to indole-3-carboxylic acid in citrus leaf tissues

International Nuclear Information System (INIS)

Sagee, O.; Riov, J.; Goren, J.

1990-01-01

Exogenous [ 14 C]indole-3-acetic acid (IAA) is conjugated in citrus (Citrus sinensis) leaf tissues to one major substance which has been identified as indole-3-acetylaspartic acid (IAAsp). Ethylene pretreatment enhanced the catabolism of [ 14 C]IAA to indole-3-carboxylic acid (ICA), which accumulated as glucose esters (ICGlu). Increased formation of ICGlu by ethylene was accompanied by a concomitant decrease in IAAsp formation. IAAsp and ICGlu were identified by combined gas chromatography-mass spectrometry. Formation of ICGlu was dependent on the concentration of ethylene and the duration of the ethylene pretreatment. It is suggested that the catabolism of IAA to ICA may be one of the mechanisms by which ethylene endogenous IAA levels

Effect of immunomodulators and cytostatics in 125I-deoxyuridine and tumor catabolism (a rapid method of antitumour immunomodulators screening)

International Nuclear Information System (INIS)

Obernikhin, S.S.; Fuks, B.B.

1992-01-01

E1-4 and P-815 murine tumor cells labelled by 125 I-deoxyuridine or 51 Cr were administered in 7-day subcutaneous syngeneic tumors or subcutaneosly. At the same time different groups of mice were treated by immunomodulators and cytostatics. It was shown that cytostatics and immunomodulators significantly delayed catabolism and withdrawing of 125 I-deoxyuridine (that has not been incorporated in DNA) from tumor cells. This delay was correlated with the inhibition of tumor nodes growth rate. It is concluded that influence of cytostatics and immunomodulators on catabolism and withdrawing rate of 125 I-deoxyuridine from tumor cells relates to their cytostatic effect and may be used at the earliest screening step of immunomodulator analysis

Anesthesia with halothane and nitrous oxide alters protein and amino acid metabolism in dogs

International Nuclear Information System (INIS)

Horber, F.F.; Krayer, S.; Rehder, K.; Haymond, M.W.

1988-01-01

General anesthesia in combination with surgery is known to result in negative nitrogen balance. To determine whether general anesthesia without concomitant surgery decreases whole body protein synthesis and/or increases whole body protein breakdown, two groups of dogs were studied: Group 1 (n = 6) in the conscious state and Group 2 (n = 8) during general anesthesia employing halothane (1.5 MAC) in 50% nitrous oxide and oxygen. Changes in protein metabolism were estimated by isotope dilution techniques employing simultaneous infusions of [4,53H]leucine and alpha-[1-14C]-ketoisocaproate (KIC). Total leucine carbon flux was unchanged or slightly increased in the anesthetized animals when compared to the conscious controls, indicating only a slight increase in the rate of proteolysis. However, leucine oxidation was increased (P less than 0.001) by more than 80% in the anesthetized animals when compared with their conscious controls, whereas whole body nonoxidative leucine disappearance, an indicator of whole body protein synthesis, was decreased. The ratio of leucine oxidation to the nonoxidative rate of leucine disappearance, which provides an index of the catabolism of at least one essential amino acid in the postabsorptive state, was more than twofold increased (P less than 0.001) in the anesthetized animals regardless of the tracer employed. These studies suggest that the administration of anesthesia alone, without concomitant surgery, is associated with a decreased rate of whole body protein synthesis and increased leucine oxidation, resulting in increased leucine and protein catabolism, which may be underlying or initiating some of the protein wasting known to occur in patients undergoing surgery

Estimation of low-dose radiation-responsive proteins in the absence of genomic instability in normal human fibroblast cells.

Science.gov (United States)

Yim, Ji-Hye; Yun, Jung Mi; Kim, Ji Young; Nam, Seon Young; Kim, Cha Soon

2017-11-01

Low-dose radiation has various biological effects such as adaptive responses, low-dose hypersensitivity, as well as beneficial effects. However, little is known about the particular proteins involved in these effects. Here, we sought to identify low-dose radiation-responsive phosphoproteins in normal fibroblast cells. We assessed genomic instability and proliferation of fibroblast cells after γ-irradiation by γ-H2AX foci and micronucleus formation analyses and BrdU incorporation assay, respectively. We screened fibroblast cells 8 h after low-dose (0.05 Gy) γ-irradiation using Phospho Explorer Antibody Microarray and validated two differentially expressed phosphoproteins using Western blotting. Cell proliferation proceeded normally in the absence of genomic instability after low-dose γ-irradiation. Phospho antibody microarray analysis and Western blotting revealed increased expression of two phosphoproteins, phospho-NFκB (Ser536) and phospho-P70S6K (Ser418), 8 h after low-dose radiation. Our findings suggest that low-dose radiation of normal fibroblast cells activates the expression of phospho-NFκB (Ser536) and phospho-P70S6K (Ser418) in the absence of genomic instability. Therefore, these proteins may be involved in DNA damage repair processes.

Increased VLDL in nephrotic patients results from a decreased catabolism while increased LDL results from increased synthesis

NARCIS (Netherlands)

de Sain-van der Velden, M; Kaysen, GA; Barrett, HA; Stellaard, F; Gadellaa, MM; Voorbij, HA; Reijngoud, DJ; Rabelink, TJ

Increased very low density lipoprotein (VLDL) in nephrotic patients results from a decreased catabolism while increased low density lipoprotein (LDL) results from increased synthesis. Hyperlipidemias a hallmark of nephrotic syndrome that has been associated with increased risk for ischemic heart

Effect of protein malnutrition on the metabolism of bone collagen in albino rats

Energy Technology Data Exchange (ETDEWEB)

Rao, J S; Rao, V H [Central Leather Research Inst., Madras (India)

1981-01-01

The effect of protein malnutrition on the metabolism of collagen in bone was studied in young female albino rats after a single injection of /sup 3/H-proline. Both specific and total radioactivities of hydroxyproline in the total collagen of the bone were found to decrease in the protein-deficient animals, indicating decreased rate of collagen synthesis. In the urine the amount of hydroxyproline excreted and total radioactivity of /sup 3/H-hydroxyproline were greatly decreased. The results of the present investigation therefore clearly indicate decreased synthesis and catabolism of collagen in bones of protein deficient animals compared to controls.

Expression of eicosanoid biosynthetic and catabolic enzymes in peritoneal endometriosis.

Science.gov (United States)

Lousse, J-C; Defrère, S; Colette, S; Van Langendonckt, A; Donnez, J

2010-03-01

Increased peritoneal eicosanoid concentrations have been reported in endometriosis patients and might be important in disease-associated pain and inflammation. Here, we evaluated the expression of key biosynthetic and catabolic enzymes involved in this abnormal eicosanoid production in peritoneal macrophages and endometriotic lesions. Peritoneal macrophages, endometriotic lesions and matched eutopic endometrium were collected from endometriosis patients (n = 40). Peritoneal macrophages and eutopic endometrium samples were also collected from disease-free women (n = 25). Expression of type IIA secretory phospholipase A(2) (sPLA(2)-IIA), cyclooxygenase-2 (COX-2), microsomal prostaglandin E synthase-1 (mPGES-1), 15-hydroxyprostaglandin dehydrogenase (15-PGDH) and 5-lipoxygenase (5-LO) was quantified by real-time PCR, and these five key enzymes were localized by immunohistochemistry. sPLA(2)-IIA, COX-2 and mPGES-1 mRNA was significantly increased in peritoneal macrophages of endometriosis patients compared with controls (P = 0.006, P = 0.016 and P = 0.025, respectively). In endometriosis patients, sPLA(2)-IIA, mPGES-1 and 15-PGDH mRNA was significantly enhanced in peritoneal lesions compared with matched eutopic endometrium (P endometriosis group compared with controls (P = 0.023). Finally, sPLA(2)-IIA, COX-2, mPGES-1 and 15-PGDH immunostaining was found mainly in endometrial glands, whereas 5-LO was distributed throughout the glands and stroma. Our study highlights an imbalance between eicosanoid biosynthesis and degradation in endometriosis patients. Both peritoneal macrophages and endometriotic lesions may be involved. Research into new molecules inhibiting biosynthetic enzymes (such as sPLA(2)-IIA and mPGES-1) and/or activating catabolic enzymes (such as 15-PGDH) may prove to be a major field of investigation in the development of targeted medical therapies.

Lipid catabolism of invertebrate predator indicates widespread wetland ecosystem degradation

Science.gov (United States)

Anteau, Michael J.; Afton, Alan D.

2011-01-01

Animals frequently undergo periods when they accumulate lipid reserves for subsequent energetically expensive activities, such as migration or breeding. During such periods, daily lipid-reserve dynamics (DLD) of sentinel species can quantify how landscape modifications affect function, health, and resilience of ecosystems. Aythya affinis (Eyton 1838; lesser scaup; diving duck) are macroinvertebrate predators; they migrate through an agriculturally dominated landscape in spring where they select wetlands with the greatest food density to refuel and accumulate lipid reserves for subsequent reproduction. We index DLD by measuring plasma-lipid metabolites of female scaup (n = 459) that were refueling at 75 spring migration stopover areas distributed across the upper Midwest, USA. We also indexed DLD for females (n = 44) refueling on a riverine site (Pool 19) south of our upper Midwest study area. We found that mean DLD estimates were significantly (P<0.05) less than zero in all ecophysiographic regions of the upper Midwest, and the greatest negative value was in the Iowa Prairie Pothole region (-31.6). Mean DLD was 16.8 at Pool 19 and was markedly greater than in any region of the upper Midwest. Our results indicate that females catabolized rather than stored lipid reserves throughout the upper Midwest. Moreover, levels of lipid catabolism are alarming, because scaup use the best quality wetlands available within a given stopover area. Accordingly, these results provide evidence of wetland ecosystem degradation across this large agricultural landscape and document affects that are carried-up through several trophic levels. Interestingly, storing of lipids by scaup at Pool 19 likely reflects similar ecosystem perturbations as observed in the upper Midwest because wetland drainage and agricultural runoff nutrifies the riverine habitat that scaup use at Pool 19. Finally, our results underscore how using this novel technique to monitor DLD, of a carefully selected sentinel

Lipid catabolism of invertebrate predator indicates widespread wetland ecosystem degradation.

Directory of Open Access Journals (Sweden)

Michael J Anteau

Full Text Available Animals frequently undergo periods when they accumulate lipid reserves for subsequent energetically expensive activities, such as migration or breeding. During such periods, daily lipid-reserve dynamics (DLD of sentinel species can quantify how landscape modifications affect function, health, and resilience of ecosystems. Aythya affinis (Eyton 1838; lesser scaup; diving duck are macroinvertebrate predators; they migrate through an agriculturally dominated landscape in spring where they select wetlands with the greatest food density to refuel and accumulate lipid reserves for subsequent reproduction. We index DLD by measuring plasma-lipid metabolites of female scaup (n = 459 that were refueling at 75 spring migration stopover areas distributed across the upper Midwest, USA. We also indexed DLD for females (n = 44 refueling on a riverine site (Pool 19 south of our upper Midwest study area. We found that mean DLD estimates were significantly (P<0.05 less than zero in all ecophysiographic regions of the upper Midwest, and the greatest negative value was in the Iowa Prairie Pothole region (-31.6. Mean DLD was 16.8 at Pool 19 and was markedly greater than in any region of the upper Midwest. Our results indicate that females catabolized rather than stored lipid reserves throughout the upper Midwest. Moreover, levels of lipid catabolism are alarming, because scaup use the best quality wetlands available within a given stopover area. Accordingly, these results provide evidence of wetland ecosystem degradation across this large agricultural landscape and document affects that are carried-up through several trophic levels. Interestingly, storing of lipids by scaup at Pool 19 likely reflects similar ecosystem perturbations as observed in the upper Midwest because wetland drainage and agricultural runoff nutrifies the riverine habitat that scaup use at Pool 19. Finally, our results underscore how using this novel technique to monitor DLD, of a carefully

Marked differences in immunocytological localization of [3H]estradiol-binding protein in rat pancreatic acinar tumor cells compared to normal acinar cells

International Nuclear Information System (INIS)

Beaudoin, A.R.; Grondin, G.; St Jean, P.; Pettengill, O.; Longnecker, D.S.; Grossman, A.

1991-01-01

[ 3 H]Estradiol can bind to a specific protein in normal rat pancreatic acinar cells. Electron microscopic immunocytochemical analysis has shown this protein to be localized primarily in the rough endoplasmic reticulum and mitochondria. Rat exocrine pancreatic tumor cell lines, whether grown in tissue culture (AR42J) or as a tumor mass after sc injection into rats (DSL-2), lacked detectable amounts of this [ 3 H]estradiol-binding protein (EBP), as determined by the dextran-coated charcoal assay. Furthermore, primary exocrine pancreatic neoplasms induced with the carcinogen azaserine contained little or no detectable [ 3 H]estradiol-binding activity. However, electron immunocytochemical studies of transformed cells indicated the presence of material that cross-reacted with antibodies prepared against the [ 3 H]EBP. The immunopositive reaction in transformed cells was localized almost exclusively in lipid granules. Such lipid organelles in normal acinar cells, although present less frequently than in transformed cells, have never been observed to contain EBP-like immunopositive material. Presumably, the aberrant localization of EBP in these acinar tumor cells results in loss of function of this protein, which in normal pancreatic acinar cells appears to exert a modulating influence on zymogen granule formation and the process of secretion

In normal human fibroblasts variation in DSB repair capacity cannot be ascribed to radiation-induced changes in the localisation, expression or activity of major NHEJ proteins

DEFF Research Database (Denmark)

Kasten-Pisula, Ulla; Vronskaja, Svetlana; Overgaard, Jens

2008-01-01

in the activity of the DNA-PK complex induced upon irradiation. CONCLUSIONS: For normal human fibroblasts, the level or activity of NHEJ proteins measured prior to or after irradiation cannot be used to predict the DSB repair capacity or cellular radiosensitivity. Udgivelsesdato: 2008-Mar......BACKGROUND AND PURPOSE: The aim of the present study was to test whether for normal human fibroblasts the variation in double-strand break (DSB) repair capacity results from radiation-induced differences in localisation, expression or activity of major non-homologous end-joining (NHEJ) proteins....... MATERIALS AND METHODS: Experiments were performed with 11 normal human fibroblast strains AF01-11. NHEJ proteins were determined by Western blot and DNA-PK activity by pulldown-assay. RESULTS: The four NHEJ proteins tested (Ku70, Ku80, XRCC4 and DNA-PKcs) were found to be localised almost exclusively...

CO₂ and O₂ respiration kinetics in hydrocarbon contaminated soils amended with organic carbon sources used to determine catabolic diversity.

Science.gov (United States)

Pietravalle, Stéphane; Aspray, Thomas J

2013-05-01

Multiple substrate induced respiration (MSIR) assays which assess the response of soils to carbon source amendment are effective approaches to determine catabolic diversity of soils. Many assays are based on a single short term (hydrocarbon contaminated soils using continuous CO2 and O2 respiration measurements. Based on cumulative CO2 and O2 measurements at 4, 24 and 120 h, the soils were found to be distinct in terms of their catabolic diversity. Most noteworthy, however, was the response to the addition of maleic acid which provided strong evidence of abiotic CO2 efflux to be the overriding process, raising questions about the interpretation of CO2 only responses from organic acid addition in MSIR assays. Copyright © 2013 Elsevier Ltd. All rights reserved.

Triple SILAC quantitative proteomic analysis reveals differential abundance of cell signaling proteins between normal and lung cancer-derived exosomes.

Science.gov (United States)

Clark, David J; Fondrie, William E; Yang, Austin; Mao, Li

2016-02-05

Exosomes are 30-100 nm sized membrane vesicles released by cells into the extracellular space that mediate intercellular communication via transfer of proteins and other biological molecules. To better understand the role of these microvesicles in lung carcinogenesis, we employed a Triple SILAC quantitative proteomic strategy to examine the differential protein abundance between exosomes derived from an immortalized normal bronchial epithelial cell line and two non-small cell lung cancer (NSCLC) cell lines harboring distinct activating mutations in the cell signaling molecules: Kirsten rat sarcoma viral oncogene homolog (KRAS) or epidermal growth factor receptor (EGFR). In total, we were able to quantify 721 exosomal proteins derived from the three cell lines. Proteins associated with signal transduction, including EGFR, GRB2 and SRC, were enriched in NSCLC exosomes, and could actively regulate cell proliferation in recipient cells. This study's investigation of the NSCLC exosomal proteome has identified enriched protein cargo that can contribute to lung cancer progression, which may have potential clinical implications in biomarker development for patients with NSCLC. The high mortality associated with lung cancer is a result of late-stage diagnosis of the disease. Current screening techniques used for early detection of lung cancer lack the specificity for accurate diagnosis. Exosomes are nano-sized extracellular vesicles, and the increased abundance of select protein cargo in exosomes derived from cancer cells may be used for diagnostic purposes. In this paper, we applied quantitative proteomic analysis to elucidate abundance differences in exosomal protein cargo between two NSCLC cell lines with distinctive oncogene mutations and an immortalized normal bronchial epithelial cell line. This study revealed proteins associated with cell adhesion, the extracellular matrix, and a variety of signaling molecules were enriched in NSCLC exosomes. The present data reveals

Seasonal changes in the abundance of bacterial genes related to dimethylsulfoniopropionate catabolism in seawater from Ofunato Bay revealed by metagenomic analysis

KAUST Repository

Kudo, Toshiaki; Kobiyama, Atsushi; Rashid, Jonaira; Reza, Shaheed; Yamada, Yuichiro; Ikeda, Yuri; Ikeda, Daisuke; Mizusawa, Nanami; Ikeo, Kazuho; Sato, Shigeru; Ogata, Takehiko; Jimbo, Mitsuru; Kaga, Shinnosuke; Watanabe, Shiho; Naiki, Kimiaki; Kaga, Yoshimasa; Segawa, Satoshi; Mineta, Katsuhiko; Bajic, Vladimir B.; Gojobori, Takashi; Watabe, Shugo

2018-01-01

Ofunato Bay is located in the northeastern Pacific Ocean area of Japan, and it has the highest biodiversity of marine organisms in the world, primarily due to tidal influences from the cold Oyashio and warm Kuroshio currents. Our previous results from performing shotgun metagenomics indicated that Candidatus Pelagibacter ubique and Planktomarina temperata were the dominant bacteria (Reza et al., 2018a, 2018b). These bacteria are reportedly able to catabolize dimethylsulfoniopropionate (DMSP) produced from phytoplankton into dimethyl sulfide (DMS) or methanethiol (MeSH). This study was focused on seasonal changes in the abundances of bacterial genes (dddP, dmdA) related to DMSP catabolism in the seawater of Ofunato Bay by BLAST+ analysis using shotgun metagenomic datasets. We found seasonal changes among the Candidatus Pelagibacter ubique strains, including those of the HTCC1062 type and the Red Sea type. A good correlation was observed between the chlorophyll a concentrations and the abundances of the catabolic genes, suggesting that the bacteria directly interact with phytoplankton in the marine material cycle system and play important roles in producing DMS and MeSH from DMSP as signaling molecules for the possible formation of the scent of the tidewater or as fish attractants.

In Planta Biocontrol of Pectobacterium atrosepticum by Rhodococcus erythropolis Involves Silencing of Pathogen Communication by the Rhodococcal Gamma-Lactone Catabolic Pathway.

Directory of Open Access Journals (Sweden)

Corinne Barbey

Full Text Available The virulence of numerous Gram-negative bacteria is under the control of a quorum sensing process based on synthesis and perception of N-acyl homoserine lactones. Rhodococcus erythropolis, a Gram-positive bacterium, has recently been proposed as a biocontrol agent for plant protection against soft-rot bacteria, including Pectobacterium. Here, we show that the γ-lactone catabolic pathway of R. erythropolis disrupts Pectobacterium communication and prevents plant soft-rot. We report the first characterization and demonstration of N-acyl homoserine lactone quenching in planta. In particular, we describe the transcription of the R. erythropolis lactonase gene, encoding the key enzyme of this pathway, and the subsequent lactone breakdown. The role of this catabolic pathway in biocontrol activity was confirmed by deletion of the lactonase gene from R. erythropolis and also its heterologous expression in Escherichia coli. The γ-lactone catabolic pathway is induced by pathogen communication rather than by pathogen invasion. This is thus a novel and unusual biocontrol pathway, differing from those previously described as protecting plants from phytopathogens. These findings also suggest the existence of an additional pathway contributing to plant protection.

Seasonal changes in the abundance of bacterial genes related to dimethylsulfoniopropionate catabolism in seawater from Ofunato Bay revealed by metagenomic analysis

KAUST Repository

Kudo, Toshiaki

2018-04-26

Ofunato Bay is located in the northeastern Pacific Ocean area of Japan, and it has the highest biodiversity of marine organisms in the world, primarily due to tidal influences from the cold Oyashio and warm Kuroshio currents. Our previous results from performing shotgun metagenomics indicated that Candidatus Pelagibacter ubique and Planktomarina temperata were the dominant bacteria (Reza et al., 2018a, 2018b). These bacteria are reportedly able to catabolize dimethylsulfoniopropionate (DMSP) produced from phytoplankton into dimethyl sulfide (DMS) or methanethiol (MeSH). This study was focused on seasonal changes in the abundances of bacterial genes (dddP, dmdA) related to DMSP catabolism in the seawater of Ofunato Bay by BLAST+ analysis using shotgun metagenomic datasets. We found seasonal changes among the Candidatus Pelagibacter ubique strains, including those of the HTCC1062 type and the Red Sea type. A good correlation was observed between the chlorophyll a concentrations and the abundances of the catabolic genes, suggesting that the bacteria directly interact with phytoplankton in the marine material cycle system and play important roles in producing DMS and MeSH from DMSP as signaling molecules for the possible formation of the scent of the tidewater or as fish attractants.

NOS3 is involved in the increased protein and arginine metabolic response in muscle during early endotoxemia in mice

NARCIS (Netherlands)

Luiking, Yvette C.; Hallemeesch, Marcella M.; Lamers, Wouter H.; Deutz, Nicolaas E. P.

2005-01-01

Sepsis is a severe catabolic condition. The loss of skeletal muscle protein mass is characterized by enhanced release of the amino acids glutamine and arginine, which (in)directly affects interorgan arginine and the related nitric oxide (NO) synthesis. To establish whether changes in muscle amino

Autophagy Proteins ATG5 and ATG7 Are Essential for the Maintenance of Human CD34+ Hematopoietic Stem-Progenitor Cells

NARCIS (Netherlands)

Gomez Puerto, Maria Catalina; Folkerts, Hendrik; Wierenga, Albertus T J; Schepers, Koen; Schuringa, Jan Jacob; Coffer, Paul J.; Vellenga, Edo

2016-01-01

Autophagy is a highly regulated catabolic process that involves sequestration and lysosomal degradation of cytosolic components such as damaged organelles and misfolded proteins. While autophagy can be considered to be a general cellular housekeeping process, it has become clear that it may also

Protein Nutrition and Malnutrition in CKD and ESRD.

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Zha, Yan; Qian, Qi

2017-02-27

Elevated protein catabolism and protein malnutrition are common in patients with chronic kidney disease (CKD) and end-stage renal disease (ESRD). The underlying etiology includes, but is not limited to, metabolic acidosis intestinal dysbiosis; systemic inflammation with activation of complements, endothelin-1 and renin-angiotensin-aldosterone (RAAS) axis; anabolic hormone resistance; energy expenditure elevation; and uremic toxin accumulation. All of these derangements can further worsen kidney function, leading to poor patient outcomes. Many of these CKD-related derangements can be prevented and substantially reversed, representing an area of great potential to improve CKD and ESRD care. This review integrates known information and recent advances in the area of protein nutrition and malnutrition in CKD and ESRD. Management recommendations are summarized. Thorough understanding the pathogenesis and etiology of protein malnutrition in CKD and ESRD patients will undoubtedly facilitate the design and development of more effective strategies to optimize protein nutrition and improve outcomes.

Turnover of pigment granules: cyclic catabolism and anabolism of ommochromes within epidermal cells.

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Insausti, T C; Casas, J

2009-12-01

Ommochromes are end products of the tryptophan metabolism in arthropods. While the anabolism of ommochromes has been well studied, the catabolism is totally unknown. In order to study it, we used the crab-spider Misumena vatia, which is able to change color reversibly in a few days, from yellow to white and back. Ommochromes is the only pigment class responsible for the body coloration in this animal. The aim of this study was to analyze the fine structure of the epidermal cells in bleaching spiders, in an attempt to correlate morphological changes with the fate of the pigment granules. Central to the process of bleaching is the lysis of the ommochrome granules. In the same cell, intact granules and granules in different degradation stages are found. The degradation begins with granule autolysis. Some components are extruded in the extracellular space and others are recycled via autophagy. Abundant glycogen appears associated to granulolysis. In a later stage of bleaching, ommochrome progranules, typical of white spiders, appear in the distal zone of the same epidermal cell. Catabolism and anabolism of pigment granules thus take place simultaneously in spider epidermal cells. A cyclic pathway of pigment granules formation and degradation, throughout a complete cycle of color change is proposed, together with an explanation for this turnover, involving photoprotection against UV by ommochromes metabolites. The presence of this turnover for melanins is discussed.

Re-Factoring Glycolytic Genes for Targeted Engineering of Catabolism in Gram-Negative Bacteria.

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Sánchez-Pascuala, Alberto; Nikel, Pablo I; de Lorenzo, Víctor

2018-01-01

The Embden-Meyerhof-Parnas (EMP) pathway is widely accepted to be the biochemical standard of glucose catabolism. The well-characterized glycolytic route of Escherichia coli, based on the EMP catabolism, is an example of an intricate pathway in terms of genomic organization of the genes involved and patterns of gene expression and regulation. This intrinsic genetic and metabolic complexity renders it difficult to engineer glycolytic activities and transfer them onto other microbial cell factories, thus limiting the biotechnological potential of bacterial hosts that lack the route. Taking into account the potential applications of such a portable tool for targeted pathway engineering, in the present protocol we describe how the genes encoding all the enzymes of the linear EMP route have been individually recruited from the genome of E. coli K-12, edited in silico to remove their endogenous regulatory signals, and synthesized de novo following a standard (i.e., GlucoBrick) that facilitates their grouping in the form of functional modules that can be combined at the user's will. This novel genetic tool allows for the à la carte implementation or boosting of EMP pathway activities into different Gram-negative bacteria. The potential of the GlucoBrick platform is further illustrated by engineering novel glycolytic activities in the most representative members of the Pseudomonas genus (Pseudomonas putida and Pseudomonas aeruginosa).

Acetone Formation in the Vibrio Family: a New Pathway for Bacterial Leucine Catabolism

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Nemecek-Marshall, Michele; Wojciechowski, Cheryl; Wagner, William P.; Fall, Ray

1999-01-01

There is current interest in biological sources of acetone, a volatile organic compound that impacts atmospheric chemistry. Here, we determined that leucine-dependent acetone formation is widespread in the Vibrionaceae. Sixteen Vibrio isolates, two Listonella species, and two Photobacterium angustum isolates produced acetone in the presence of l-leucine. Shewanella isolates produced much less acetone. Growth of Vibrio splendidus and P. angustum in a fermentor with controlled aeration revealed that acetone was produced after a lag in late logarithmic or stationary phase of growth, depending on the medium, and was not derived from acetoacetate by nonenzymatic decarboxylation in the medium. l-Leucine, but not d-leucine, was converted to acetone with a stoichiometry of approximately 0.61 mol of acetone per mol of l-leucine. Testing various potential leucine catabolites as precursors of acetone showed that only α-ketoisocaproate was efficiently converted by whole cells to acetone. Acetone production was blocked by a nitrogen atmosphere but not by electron transport inhibitors, suggesting that an oxygen-dependent reaction is required for leucine catabolism. Metabolic labeling with deuterated (isopropyl-d7)-l-leucine revealed that the isopropyl carbons give rise to acetone with full retention of deuterium in each methyl group. These results suggest the operation of a new catabolic pathway for leucine in vibrios that is distinct from the 3-hydroxy-3-methylglutaryl-coenzyme A pathway seen in pseudomonads. PMID:10601206

Spatial Expression of Otolith Matrix Protein-1 and Otolin-1 in Normally and Kinetotically Swimming Fish.

Science.gov (United States)

Weigele, Jochen; Franz-Odendaal, Tamara A; Hilbig, Reinhard

2015-10-01

Kinetosis (motion sickness) has been repeatedly shown to affect some fish of a given clutch following the transition from 1g to microgravity or from hypergravity to 1g. This susceptibility to kinetosis may be correlated with irregular inner ear otolith growth. Otoliths are mainly composed of calcium carbonate and matrix proteins, which play an important role in the process of otolith mineralization. Here, we examine the morphology of otoliths and the expression pattern of the major otolith proteins OMP-1 and otolin-1 in a series of hypergravity experiments. In the utricle, OMP-1 is present in centripetal (medial) and centrifugal (lateral) regions of the meshwork area. In the saccule, OMP-1 was expressed within a dorsal and a ventral narrow band of the meshwork area opposite to the periphery of the sulcus acusticus. In normal animals, the spatial expression pattern of OMP-1 reaches more posteriorly in the centrifugal aspect and is considerably broader in the centripetal portion of the utricle compared to kinetotic animals. However, otolin-1 was not expressed in the utricule. In the saccule, no differences were observed for either gene when comparing normal and kinetotically behaving fish. The difference in the utricular OMP-1 expression pattern between normally and kinetotically swimming fish indicates a different otolith morphology and thus a different geometry of the otoliths resting on the corresponding sensory maculae. As the utricle is the endorgan responsible for sensing gravity, the aberrant morphology of the utricular otoliths, based on OMP-1 expression, likely leads to the observed kinetotic behavior. © 2015 Wiley Periodicals, Inc.

Protein and Carbohydrate Accumulation in Normal and High-Lysine Barley in Spike Culture

DEFF Research Database (Denmark)

Mather, D.E; Giese, Nanna Henriette

1984-01-01

Spikes of barley cv. Bomi and high-lysine mutants Riso 1508 and Riso 56 were cultured on liquid media at varying N and sucrose levels. Bomi accumulated N in response to increasing N levels in the medium and a higher level was reached than in spikes of intact plants. The distribution of N in salt......-soluble, hordein, and non-protein N fractions appeared to be normal. Endosperm dry weight and starch were lower than in intact plants and declined at higher N levels. A linear relationship was observed between starch content and the concentration of sucrose in the endosperm water. Uptake of culture medium...

Model-free methods of analyzing domain motions in proteins from simulation : A comparison of normal mode analysis and molecular dynamics simulation of lysozyme

NARCIS (Netherlands)

Hayward, S.; Kitao, A.; Berendsen, H.J.C.

Model-free methods are introduced to determine quantities pertaining to protein domain motions from normal mode analyses and molecular dynamics simulations, For the normal mode analysis, the methods are based on the assumption that in low frequency modes, domain motions can be well approximated by

Leucine and protein metabolism in obese Zucker rats.

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Pengxiang She

Full Text Available Branched-chain amino acids (BCAAs are circulating nutrient signals for protein accretion, however, they increase in obesity and elevations appear to be prognostic of diabetes. To understand the mechanisms whereby obesity affects BCAAs and protein metabolism, we employed metabolomics and measured rates of [1-(14C]-leucine metabolism, tissue-specific protein synthesis and branched-chain keto-acid (BCKA dehydrogenase complex (BCKDC activities. Male obese Zucker rats (11-weeks old had increased body weight (BW, 53%, liver (107% and fat (∼300%, but lower plantaris and gastrocnemius masses (-21-24%. Plasma BCAAs and BCKAs were elevated 45-69% and ∼100%, respectively, in obese rats. Processes facilitating these rises appeared to include increased dietary intake (23%, leucine (Leu turnover and proteolysis [35% per g fat free mass (FFM, urinary markers of proteolysis: 3-methylhistidine (183% and 4-hydroxyproline (766%] and decreased BCKDC per g kidney, heart, gastrocnemius and liver (-47-66%. A process disposing of circulating BCAAs, protein synthesis, was increased 23-29% by obesity in whole-body (FFM corrected, gastrocnemius and liver. Despite the observed decreases in BCKDC activities per gm tissue, rates of whole-body Leu oxidation in obese rats were 22% and 59% higher normalized to BW and FFM, respectively. Consistently, urinary concentrations of eight BCAA catabolism-derived acylcarnitines were also elevated. The unexpected increase in BCAA oxidation may be due to a substrate effect in liver. Supporting this idea, BCKAs were elevated more in liver (193-418% than plasma or muscle, and per g losses of hepatic BCKDC activities were completely offset by increased liver mass, in contrast to other tissues. In summary, our results indicate that plasma BCKAs may represent a more sensitive metabolic signature for obesity than BCAAs. Processes supporting elevated BCAA]BCKAs in the obese Zucker rat include increased dietary intake, Leu and protein

The Alzheimer's disease-associated amyloid beta-protein is an antimicrobial peptide.

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Stephanie J Soscia

2010-03-01

Full Text Available The amyloid beta-protein (Abeta is believed to be the key mediator of Alzheimer's disease (AD pathology. Abeta is most often characterized as an incidental catabolic byproduct that lacks a normal physiological role. However, Abeta has been shown to be a specific ligand for a number of different receptors and other molecules, transported by complex trafficking pathways, modulated in response to a variety of environmental stressors, and able to induce pro-inflammatory activities.Here, we provide data supporting an in vivo function for Abeta as an antimicrobial peptide (AMP. Experiments used established in vitro assays to compare antimicrobial activities of Abeta and LL-37, an archetypical human AMP. Findings reveal that Abeta exerts antimicrobial activity against eight common and clinically relevant microorganisms with a potency equivalent to, and in some cases greater than, LL-37. Furthermore, we show that AD whole brain homogenates have significantly higher antimicrobial activity than aged matched non-AD samples and that AMP action correlates with tissue Abeta levels. Consistent with Abeta-mediated activity, the increased antimicrobial action was ablated by immunodepletion of AD brain homogenates with anti-Abeta antibodies.Our findings suggest Abeta is a hitherto unrecognized AMP that may normally function in the innate immune system. This finding stands in stark contrast to current models of Abeta-mediated pathology and has important implications for ongoing and future AD treatment strategies.

Calmodulin and calmodulin-binding proteins in cystic fibrosis and normal human fibroblasts

International Nuclear Information System (INIS)

Tallant, E.A.; Wallace, R.W.

1986-01-01

The authors have investigated the possibility that a lesion in a calmodulin (CaM)-dependent regulatory mechanism may be involved in cystic fibrosis (CF). The level of CaM, CaM-binding proteins (CaM-BP) and a CaM-dependent phosphatase (CaM-Ptase) have been compared in cultured fibroblasts from CF patients versus age- and sex-matched control subjects. The CaM concentration, measured by radioimmunoassay, ranged from 0.20 to 0.76 μg/mg protein (n=8); there was no significant difference in the average CaM concentration from CF patients vs controls. Using Western blotting techniques with 125 I-CaM, they detected at least ten distinct CaM-BPs in fibroblasts with molecular weights ranging from 230K to 37K; the only consistent difference between control and CF cell lines was in a 46.5K CaM-BP, which was depressed in all three CF samples. The 46.5 K CaM-BP was found only in the particulate fraction. A 59K CaM-BP was identified as a CaM-Ptase by its crossreactivity with an antibody against a brain CaM-Ptase. There was no significant difference in CaM-Ptase activity or in the amount of the phosphatase as determined by radioimmunoassay in CF vs. normal samples (n=8). Thus, the level of CaM as well as its various enzymes and proteins do not appear to be altered in CF fibroblasts except for a CaM-BP of 46.5K, the identity of which is currently being investigated

Nitrogen Balance and Protein Requirements for Critically Ill Older Patients

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Roland N. Dickerson

2016-04-01

Full Text Available Critically ill older patients with sarcopenia experience greater morbidity and mortality than younger patients. It is anticipated that unabated protein catabolism would be detrimental for the critically ill older patient. Healthy older subjects experience a diminished response to protein supplementation when compared to their younger counterparts, but this anabolic resistance can be overcome by increasing protein intake. Preliminary evidence suggests that older patients may respond differently to protein intake than younger patients during critical illness as well. If sufficient protein intake is given, older patients can achieve a similar nitrogen accretion response as younger patients even during critical illness. However, there is concern among some clinicians that increasing protein intake in older patients during critical illness may lead to azotemia due to decreased renal functional reserve which may augment the propensity towards worsened renal function and worsened clinical outcomes. Current evidence regarding protein requirements, nitrogen balance, ureagenesis, and clinical outcomes during nutritional therapy for critically ill older patients is reviewed.

STAT proteins: from normal control of cellular events to tumorigenesis.

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Calò, Valentina; Migliavacca, Manuela; Bazan, Viviana; Macaluso, Marcella; Buscemi, Maria; Gebbia, Nicola; Russo, Antonio

2003-11-01

Signal transducers and activators of transcription (STAT) proteins comprise a family of transcription factors latent in the cytoplasm that participate in normal cellular events, such as differentiation, proliferation, cell survival, apoptosis, and angiogenesis following cytokine, growth factor, and hormone signaling. STATs are activated by tyrosine phosphorylation, which is normally a transient and tightly regulates process. Nevertheless, several constitutively activated STATs have been observed in a wide number of human cancer cell lines and primary tumors, including blood malignancies and solid neoplasias. STATs can be divided into two groups according to their specific functions. One is made up of STAT2, STAT4, and STAT6, which are activated by a small number of cytokines and play a distinct role in the development of T-cells and in IFNgamma signaling. The other group includes STAT1, STAT3, and STAT5, activated in different tissues by means of a series of ligands and involved in IFN signaling, development of the mammary gland, response to GH, and embriogenesis. This latter group of STATS plays an important role in controlling cell-cycle progression and apoptosis and thus contributes to oncogenesis. Although an increased expression of STAT1 has been observed in many human neoplasias, this molecule can be considered a potential tumor suppressor, since it plays an important role in growth arrest and in promoting apoptosis. On the other hand, STAT3 and 5 are considered as oncogenes, since they bring about the activation of cyclin D1, c-Myc, and bcl-xl expression, and are involved in promoting cell-cycle progression, cellular transformation, and in preventing apoptosis.

All-atom normal-mode analysis reveals an RNA-induced allostery in a bacteriophage coat protein.

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Dykeman, Eric C; Twarock, Reidun

2010-03-01

Assembly of the T=3 bacteriophage MS2 is initiated by the binding of a 19 nucleotide RNA stem loop from within the phage genome to a symmetric coat protein dimer. This binding event effects a folding of the FG loop in one of the protein subunits of the dimer and results in the formation of an asymmetric dimer. Since both the symmetric and asymmetric forms of the dimer are needed for the assembly of the protein container, this allosteric switch plays an important role in the life cycle of the phage. We provide here details of an all-atom normal-mode analysis of this allosteric effect. The results suggest that asymmetric contacts between the A -duplex RNA phosphodiester backbone of the stem loop with the EF loop in one coat protein subunit results in an increased dynamic behavior of its FG loop. The four lowest-frequency modes, which encompass motions predominantly on the FG loops, account for over 90% of the increased dynamic behavior due to a localization of the vibrational pattern on a single FG loop. Finally, we show that an analysis of the allosteric effect using an elastic network model fails to predict this localization effect, highlighting the importance of using an all-atom full force field method for this problem.

Catabolism of indole-3-acetic acid and 4- and 5-chloroindole-3-acetic acid in Bradyrhizobium japonicum

DEFF Research Database (Denmark)

Jensen, J B; Egsgaard, H; Van Onckelen, H

1995-01-01

Some strains of Bradyrhizobium japonicum have the ability to catabolize indole-3-acetic acid. Indoleacetic acid (IAA), 4-chloro-IAA (4-Cl-IAA), and 5-Cl-IAA were metabolized to different extents by strains 61A24 and 110. Metabolites were isolated and analyzed by high-performance liquid chromatogr...

Whey protein supplementation does not alter plasma branched-chained amino acid profiles but results in unique metabolomics patterns in obese women enrolled in an 8-week weight loss trial.

Science.gov (United States)

Piccolo, Brian D; Comerford, Kevin B; Karakas, Sidika E; Knotts, Trina A; Fiehn, Oliver; Adams, Sean H

2015-04-01

It has been suggested that perturbations in branched-chain amino acid (BCAA) catabolism are associated with insulin resistance and contribute to elevated systemic BCAAs. Evidence in rodents suggests dietary protein rich in BCAAs can increase BCAA catabolism, but there is limited evidence in humans. We hypothesize that a diet rich in BCAAs will increase BCAA catabolism, which will manifest in a reduction of fasting plasma BCAA concentrations. The metabolome of 27 obese women with metabolic syndrome before and after weight loss was investigated to identify changes in BCAA metabolism using GC-time-of-flight mass spectrometry. Subjects were enrolled in an 8-wk weight-loss study including either a 20-g/d whey (whey group, n = 16) or gelatin (gelatin group, n = 11) protein supplement. When matched for total protein by weight, whey protein has 3 times the amount of BCAAs compared with gelatin protein. Postintervention plasma abundances of Ile (gelatin group: 637 ± 18, quantifier ion peak height ÷ 100; whey group: 744 ± 65), Leu (gelatin group: 1210 ± 33; whey group: 1380 ± 79), and Val (gelatin group: 2080 ± 59; whey group: 2510 ± 230) did not differ between treatment groups. BCAAs were significantly correlated with homeostasis model assessment of insulin resistance at baseline (r = 0.52, 0.43, and 0.49 for Leu, Ile, and Val, respectively; all, P BCAA metabolism is, at best, only modestly affected at a whey protein supplementation dose of 20 g/d. Furthermore, the loss of an association between postintervention BCAA and homeostasis model assessment suggests that factors associated with calorie restriction or protein intake affect how plasma BCAAs relate to insulin sensitivity. This trial was registered at clinicaltrials.gov as NCT00739479. © 2015 American Society for Nutrition.

Effects of ingesting protein with various forms of carbohydrate following resistance-exercise on substrate availability and markers of anabolism, catabolism, and immunity

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Greenwood Michael

2007-11-01

Full Text Available Abstract Background Ingestion of carbohydrate (CHO and protein (PRO following intense exercise has been reported to increase insulin levels, optimize glycogen resynthesis, enhance PRO synthesis, and lessen the immuno-suppressive effects of intense exercise. Since different forms of CHO have varying glycemic effects, the purpose of this study was to determine whether the type of CHO ingested with PRO following resistance-exercise affects blood glucose availability and insulin levels, markers of anabolism and catabolism, and/or general immune markers. Methods 40 resistance-trained subjects performed a standardized resistance training workout and then ingested in a double blind and randomized manner 40 g of whey PRO with 120 g of sucrose (S, honey powder (H, or maltodextrin (M. A non-supplemented control group (C was also evaluated. Blood samples were collected prior to and following exercise as well as 30, 60, 90, and 120 min after ingestion of the supplements. Data were analyzed by repeated measures ANOVA or ANCOVA using baseline values as a covariate if necessary. Results Glucose concentration 30 min following ingestion showed the H group (7.12 ± 0.2 mmol/L to be greater than S (5.53 ± 0.6 mmol/L; p uIU/mL, H (150.1 ± 25.39 uIU/mL, and M (154.8 ± 18.9 uIU/mL were greater than C (8.7 ± 2.9 uIU/mL as was AUC with no significant differences observed among types of CHO. No significant group × time effects were observed among groups in testosterone, cortisol, the ratio of testosterone to cortisol, muscle and liver enzymes, or general markers of immunity. Conclusion CHO and PRO ingestion following exercise significantly influences glucose and insulin concentrations. Although some trends were observed suggesting that H maintained blood glucose levels to a better degree, no significant differences were observed among types of CHO ingested on insulin levels. These findings suggest that each of these forms of CHO can serve as effective sources of

The Differential Expression of Aqueous Soluble Proteins in Breast Normal and Cancerous Tissues in Relation to Ethnicity of the Patients; Chinese, Malay and Indian

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Seng Liang

2010-01-01

Full Text Available Female breast cancer is one of the leading causes of female mortality worldwide. In Malaysia, breast cancer is the most commonly diagnosed cancer in women. Of the women in Malaysia, the Chinese have the highest number of breast cancer cases, followed by the Indian and the Malay. The most common type of breast cancer is infiltrating ductal carcinoma (IDC. A proteomic approach was applied in this study to identify changes in the protein profile of cancerous tissues compared with normal tissues from 18 patients; 8 Chinese, 6 Malay and 4 Indian were analysed. Twenty-four differentially expressed hydrophilic proteins were identified. We evaluated the potential of these proteins as biomarkers for infiltrating ductal carcinoma based on their ethnic-specific expressions. Three of the upregulated proteins, calreticulin, 14-3-3 protein zeta and 14-3-3 protein eta, were found to be expressed at a significantly higher level in the cancerous breast tissues when compared with the normal tissues in cases of infiltrating ductal carcinoma. The upregulation in expression was particularly dominant in the Malay cohort.

An early function of the adenoviral E1B 55 kDa protein is required for the nuclear relocalization of the cellular p53 protein in adenovirus-infected normal human cells

International Nuclear Information System (INIS)

Cardoso, F.M.; Kato, Sayuri E.M.; Huang Wenying; Flint, S. Jane; Gonzalez, Ramon A.

2008-01-01

It is well established that the human subgroup C adenovirus type 5 (Ad5) E1B 55 kDa protein can regulate the activity and concentration of the cellular tumor suppressor, p53. However, the contribution(s) of these functions of the E1B protein to viral reproduction remains unclear. To investigate this issue, we examined properties of p53 in normal human cells infected by E1B mutant viruses that display defective entry into the late phase or viral late mRNA export. The steady-state concentrations of p53 were significantly higher in cells infected by the E1B 55 kDa null mutant Hr6 or three mutants carrying small insertions in the E1B 55 kDa protein coding sequence than in Ad5-infected cells. Nevertheless, none of the mutants induced apoptosis in infected cells. Rather, the localization of p53 to E1B containing nuclear sites observed during infection by Ad5 was prevented by mutations that impair interaction of the E1B protein with p53 and/or with the E4 Orf6 protein. These results indicate that the E1B protein fulfills an early function that correlates efficient entry into the late phase with the localization of E1B and p53 in the nucleus of Ad5-infected normal human cells

The acyl-CoA binding protein is required for normal epidermal barrier function in mice

DEFF Research Database (Denmark)

Bloksgaard, Maria; Bek, Signe; Marcher, Ann-Britt

2012-01-01

(+/+) and ACBP(-/-) mice showed very similar composition, except for a significant and specific decrease in the very long chain free fatty acids (VLC-FFA) in stratum corneum of ACBP(-/-) mice. This finding indicates that ACBP is critically involved in the processes that lead to production of stratum corneum VLC......The acyl-CoA binding protein (ACBP) is a 10 kDa intracellular protein expressed in all eukaryotic species. Mice with targeted disruption of Acbp (ACBP(-/-) mice) are viable and fertile but present a visible skin and fur phenotype characterized by greasy fur and development of alopecia and scaling...... with age. Morphology and development of skin and appendages are normal in ACBP(-/-) mice; however, the stratum corneum display altered biophysical properties with reduced proton activity and decreased water content. Mass spectrometry analyses of lipids from epidermis and stratum corneum of ACBP...

Quantitative proteome profiling of normal human circulating microparticles

DEFF Research Database (Denmark)

Østergaard, Ole; Nielsen, Christoffer T; Iversen, Line V

2012-01-01

Circulating microparticles (MPs) are produced as part of normal physiology. Their numbers, origin, and composition change in pathology. Despite this, the normal MP proteome has not yet been characterized with standardized high-resolution methods. We here quantitatively profile the normal MP...... proteome using nano-LC-MS/MS on an LTQ-Orbitrap with optimized sample collection, preparation, and analysis of 12 different normal samples. Analytical and procedural variation were estimated in triply processed samples analyzed in triplicate from two different donors. Label-free quantitation was validated...... by the correlation of cytoskeletal protein intensities with MP numbers obtained by flow cytometry. Finally, the validity of using pooled samples was evaluated using overlap protein identification numbers and multivariate data analysis. Using conservative parameters, 536 different unique proteins were quantitated...

Dendritic protein synthesis in the normal and diseased brain

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Swanger, Sharon A.; Bassell, Gary J.

2015-01-01

Synaptic activity is a spatially-limited process that requires a precise, yet dynamic, complement of proteins within the synaptic micro-domain. The maintenance and regulation of these synaptic proteins is regulated, in part, by local mRNA translation in dendrites. Protein synthesis within the postsynaptic compartment allows neurons tight spatial and temporal control of synaptic protein expression, which is critical for proper functioning of synapses and neural circuits. In this review, we discuss the identity of proteins synthesized within dendrites, the receptor-mediated mechanisms regulating their synthesis, and the possible roles for these locally synthesized proteins. We also explore how our current understanding of dendritic protein synthesis in the hippocampus can be applied to new brain regions and to understanding the pathological mechanisms underlying varied neurological diseases. PMID:23262237

Hematopoietic properties of granulocyte colony-stimulating factor/immunoglobulin (G-CSF/IgG-Fc fusion proteins in normal and neutropenic rodents.

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George N Cox

Full Text Available Previously we showed that granulocyte colony-stimulating factor (G-CSF in vitro bioactivity is preserved when the protein is joined via a flexible 7 amino acid linker to an immunoglobulin-1 (IgG1-Fc domain and that the G-CSF/IgG1-Fc fusion protein possessed a longer circulating half-life and improved hematopoietic properties compared to G-CSF in normal rats. We have extended this analysis by comparing the relative hematopoietic potencies of G-CSF/IgG1-Fc to G-CSF in normal mice and to G-CSF and polyethylene glycol (PEG -modified G-CSF in neutropenic rats. Mice were treated for 5 days using different doses and dosing regimens of G-CSF/IgG1-Fc or G-CSF and circulating neutrophil levels in the animals measured on Day 6. G-CSF/IgG1-Fc stimulated greater increases in blood neutrophils than comparable doses of G-CSF when administered using daily, every other day or every third day dosing regimens. In rats made neutropenic with cyclophosphamide, G-CSF/IgG1-Fc accelerated recovery of blood neutrophils to normal levels (from Day 9 to Day 5 when administered as 5 daily injections or as a single injection on Day 1. By contrast, G-CSF accelerated neutrophil recovery when administered as 5 daily injections, but not when administered as a single injection. G-CSF/IgG1-Fc was as effective as PEG-G-CSF at accelerating neutrophil recovery following a single injection in neutropenic rats. G-CSF/IgG1-Fc and G-CSF/IgG4-Fc fusion proteins in which the 7 amino acid linker was deleted also were effective at accelerating neutrophil recovery following a single injection in neutropenic rats. These studies confirm the enhanced in vivo hematopoietic properties of G-CSF/IgG-Fc fusion proteins.

Influence of Hepatitis C Virus Sustained Virological Response on Immunosuppressive Tryptophan Catabolism in ART-Treated HIV/HCV Coinfected Patients

NARCIS (Netherlands)

Jenabian, Mohammad-Ali; Mehraj, Vikram; Costiniuk, Cecilia T.; Vyboh, Kishanda; Kema, Ido; Rollet, Kathleen; Ramirez, Robert Paulino; Klein, Marina B.; Routy, Jean-Pierre

2016-01-01

Background: We previously reported an association between tryptophan (Trp) catabolism and immune dysfunction in HIV monoinfection. Coinfection with HIV is associated with more rapid evolution of hepatitis C virus (HCV)-associated liver disease despite antiretroviral therapy (ART), possibly due to

Catabolism of Phenol and Its Derivatives in Bacteria: Genes, Their Regulation, and Use in the Biodegradation of Toxic Pollutants

Czech Academy of Sciences Publication Activity Database

Nešvera, Jan; Rucká, Lenka; Pátek, Miroslav

2015-01-01

Roč. 93, č. 2015 (2015), s. 107-160 ISSN 0065-2164 R&D Projects: GA TA ČR TA04021212 Institutional support: RVO:61388971 Keywords : Biodegradation * Bioremediation * Phenol catabolism Subject RIV: EE - Microbiology, Virology Impact factor: 4.128, year: 2015

HMB attenuates muscle loss during sustained energy deficit induced by calorie restriction and endurance exercise.

Science.gov (United States)

Park, Bong-Sup; Henning, Paul C; Grant, Samuel C; Lee, Won Jun; Lee, Sang-Rok; Arjmandi, Bahram H; Kim, Jeong-Su

2013-12-01

To investigate the efficacy and underlying mechanisms of β-hydroxy-β-methylbutyrate (HMB) on body composition, muscle mass and physical performance under catabolic versus normal training conditions. Mice were divided into four groups (n=10/group): (1) ALT=ad libitum+trained (1 h/d for 3 d/wk); (2) ALTH=ALT+HMB (0.5 g/kg BW/d); (3) C=calorie restricted (-30%)+trained (6 h/d, 6 d/wk); and (4) CH=C+HMB. Repeated in vivo assessments included body composition, grip strength and sensorimotor coordination before and after the experimental protocol, while in vitro analyses included muscle wet weights, expression of selected genes and proteins regulating muscle mass, and myofiber cross-sectional area. ANOVAs were used with significance set at pHMB improves body composition and sensorimotor function during normal training and attenuates muscle mass and strength loss during catabolic conditions. © 2013.

LSM Proteins Provide Accurate Splicing and Decay of Selected Transcripts to Ensure Normal Arabidopsis Development[W

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Perea-Resa, Carlos; Hernández-Verdeja, Tamara; López-Cobollo, Rosa; Castellano, María del Mar; Salinas, Julio

2012-01-01

In yeast and animals, SM-like (LSM) proteins typically exist as heptameric complexes and are involved in different aspects of RNA metabolism. Eight LSM proteins, LSM1 to 8, are highly conserved and form two distinct heteroheptameric complexes, LSM1-7 and LSM2-8,that function in mRNA decay and splicing, respectively. A search of the Arabidopsis thaliana genome identifies 11 genes encoding proteins related to the eight conserved LSMs, the genes encoding the putative LSM1, LSM3, and LSM6 proteins being duplicated. Here, we report the molecular and functional characterization of the Arabidopsis LSM gene family. Our results show that the 11 LSM genes are active and encode proteins that are also organized in two different heptameric complexes. The LSM1-7 complex is cytoplasmic and is involved in P-body formation and mRNA decay by promoting decapping. The LSM2-8 complex is nuclear and is required for precursor mRNA splicing through U6 small nuclear RNA stabilization. More importantly, our results also reveal that these complexes are essential for the correct turnover and splicing of selected development-related mRNAs and for the normal development of Arabidopsis. We propose that LSMs play a critical role in Arabidopsis development by ensuring the appropriate development-related gene expression through the regulation of mRNA splicing and decay. PMID:23221597

Bovine lactoferricin is anti-inflammatory and anti-catabolic in human articular cartilage and synovium.

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Yan, Dongyao; Chen, Di; Shen, Jie; Xiao, Guozhi; van Wijnen, Andre J; Im, Hee-Jeong

2013-02-01

Bovine lactoferricin (LfcinB) is a multi-functional peptide derived from proteolytic cleavage of bovine lactoferrin. LfcinB was found to antagonize the biological effects mediated by angiogenic growth factors such as vascular endothelial growth factor (VEGF) and fibroblast growth factor 2 (FGF-2) in endothelial cells. However, the effect of LfcinB on human articular cartilage remained unknown. Here, our findings demonstrate that LfcinB restored the proteoglycan loss promoted by catabolic factors (interleukin-1β) IL-1β and FGF-2 in vitro and ex vivo. Mechanistically, LfcinB attenuated the effects of IL-1β and FGF-2 on the expression of cartilage-degrading enzymes (MMP-1, MMP-3, and MMP-13), destructive cytokines (IL-1β and IL-6), and inflammatory mediators (iNOS and TLR2). LfcinB induced protective cytokine expression (IL-4 and IL-10), and downregulated aggrecanase basal expression. LfcinB specifically activated ERK MAPK and Akt signaling pathways, which may account for its anti-inflammatory activity. We also revealed that LfcinB exerted similar protective effects on human synovial fibroblasts challenged by IL-1β, with minimal cytotoxicity. Collectively, our results suggest that LfcinB possesses potent anti-catabolic and anti-inflammatory bioactivities in human articular tissues, and may be utilized for the prevention and/or treatment of OA in the future. Copyright © 2012 Wiley Periodicals, Inc.

Normal mode analysis and applications in biological physics.

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Dykeman, Eric C; Sankey, Otto F

2010-10-27

Normal mode analysis has become a popular and often used theoretical tool in the study of functional motions in enzymes, viruses, and large protein assemblies. The use of normal modes in the study of these motions is often extremely fruitful since many of the functional motions of large proteins can be described using just a few normal modes which are intimately related to the overall structure of the protein. In this review, we present a broad overview of several popular methods used in the study of normal modes in biological physics including continuum elastic theory, the elastic network model, and a new all-atom method, recently developed, which is capable of computing a subset of the low frequency vibrational modes exactly. After a review of the various methods, we present several examples of applications of normal modes in the study of functional motions, with an emphasis on viral capsids.

Evidence of non-coincidence of normalized sigmoidal curves of two different structural properties for two-state protein folding/unfolding

International Nuclear Information System (INIS)

Rahaman, Hamidur; Khan, Md. Khurshid Alam; Hassan, Md. Imtaiyaz; Islam, Asimul; Moosavi-Movahedi, Ali Akbar; Ahmad, Faizan

2013-01-01

Highlights: ► Non-coincidence of normalized sigmoidal curves of two different structural properties is consistence with the two-state protein folding/unfolding. ► DSC measurements of denaturation show a two-state behavior of g-cyt-c at pH 6.0. ► Urea-induced denaturation of g-cyt-c is a variable two- state process at pH 6.0. ► GdmCl-induced denaturation of g-cyt-c is a fixed two- state process at pH 6.0. -- Abstract: In practice, the observation of non-coincidence of normalized sigmoidal transition curves measured by two different structural properties constitutes a proof of existence of thermodynamically stable intermediate(s) on the folding ↔ unfolding pathway of a protein. Here we give first experimental evidence that this non-coincidence is also observed for a two-state protein denaturation. Proof of this evidence comes from our studies of denaturation of goat cytochrome-c (g-cyt-c) at pH 6.0. These studies involve differential scanning calorimetry (DSC) measurements in the absence of urea and measurements of urea-induced denaturation curves monitored by observing changes in absorbance at 405, 530, and 695 nm and circular dichroism (CD) at 222, 405, and 416 nm. DSC measurements showed that denaturation of the protein is a two-state process, for calorimetric and van’t Hoff enthalpy changes are, within experimental errors, identical. Normalization of urea-induced denaturation curves monitored by optical properties leads to noncoincident sigmoidal curves. Heat-induced transition of g-cyt-c in the presence of different urea concentrations was monitored by CD at 222 nm and absorption at 405 nm. It was observed that these two different structural probes gave not only identical values of T m (transition temperature), ΔH m (change in enthalpy at T m ) and ΔC p (constant-pressure heat capacity change), but these thermodynamic parameters in the absence of urea are also in agreement with those obtained from DSC measurements

Metabolic variations of fatty acid in isolated rat heart reperfused after a transient global ischemia

International Nuclear Information System (INIS)

Huang Gang; Michel Comet; Zhao Huiyang; Zhu Cuiying; Yuan Jimin

1998-01-01

Purpose: The fatty acid metabolism and the effect of glucose on it were studied in isolated and reperfused rat heat. Methods: 32 isolated working rat hearts were perfused in Langengdorff device with modified Krebs and were divided into normal and ischemia-reperfused group. Each group was also classified into two subgroups, modified krebs with or without glucose subgroup. 131 I-HA was injected into aorta of isolated working rat heart and then the radio-residue curves were acquired. Results: When the isolated rat hearts were perfused with krebs plus glucose, the catabolism of fatty acid was significantly decreased in normal group, but a remarkable increase of fatty acid catabolism was found in ischemia-reperfused group. While the isolated rat hearts were perfused with krebs without glucose, the catabolism of fatty acid in ischemia-reperfused isolated rat hearts were perfused with krebs without glucose, the catabolism of fatty acid in ischemia-reperfused isolated rat heart was less than that in normal group. Conclusions: Transient ischemia damages the catabolism of myocardial fatty acid in mitochondria in some degree. In normal isolated working rat heart, the principal energy source is glucose. However, the major energy source is switched to catabolism of fatty acid in ischemia-reperfused isolated rat heart. This phenomenon may be related to compensative increase of fatty acid catabolism for replenishing the loss of energy during ischemia

Parietal podocytes in normal human glomeruli.

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Bariety, Jean; Mandet, Chantal; Hill, Gary S; Bruneval, Patrick

2006-10-01

Although parietal podocytes along the Bowman's capsule have been described by electron microscopy in the normal human kidney, their molecular composition remains unknown. Ten human normal kidneys that were removed for cancer were assessed for the presence and the extent of parietal podocytes along the Bowman's capsule. The expression of podocyte-specific proteins (podocalyxin, glomerular epithelial protein-1, podocin, nephrin, synaptopodin, and alpha-actinin-4), podocyte synthesized proteins (vascular endothelial growth factor and novH), transcription factors (WT1 and PAX2), cyclin-dependent kinase inhibitor p57, and intermediate filaments (cytokeratins and vimentin) was tested. In addition, six normal fetal kidneys were studied to track the ontogeny of parietal podocytes. The podocyte protein labeling detected parietal podocytes in all of the kidneys, was found in 76.6% on average of Bowman's capsule sections, and was prominent at the vascular pole. WT1 and p57 were expressed in some parietal cells, whereas PAX2 was present in all or most of them, so some parietal cells coexpressed WT1 and PAX2. Furthermore, parietal podocytes coexpressed WT1 and podocyte proteins. Cytokeratin-positive cells covered a variable part of the capsule and did not express podocyte proteins. Tuft-capsular podocyte bridges were present in 15.5 +/- 3.7% of the glomerular sections. Parietal podocytes often covered the juxtaglomerular arterioles and were present within the extraglomerular mesangium. Parietal podocytes were present in fetal kidneys. Parietal podocytes that express the same epitopes as visceral podocytes do exist along Bowman's capsule in the normal adult kidney. They are a constitutive cell type of the Bowman's capsule. Therefore, their role in physiology and pathology should be investigated.

Leucine stimulation of skeletal muscle protein synthesis

International Nuclear Information System (INIS)

Layman, D.K.; Grogan, C.K.

1986-01-01

Previous work in this laboratory has demonstrated a stimulatory effect of leucine on skeletal muscle protein synthesis measured in vitro during catabolic conditions. Studies in other laboratories have consistently found this effect in diaphragm muscle, however, studies examining effects on nitrogen balance or with in vivo protein synthesis in skeletal muscle are equivocal. This experiment was designed to determine the potential of leucine to stimulate skeletal muscle protein synthesis in vivo. Male Sprague-Dawley rats weighing 200 g were fasted for 12 hrs, anesthetized, a jugular cannula inserted, and protein synthesis measured using a primed continuous infusion of 14 C-tyrosine. A plateau in specific activity was reached after 30 to 60 min and maintained for 3 hrs. The leucine dose consisted of a 240 umole priming dose followed by a continuous infusion of 160 umoles/hr. Leucine infusion stimulated protein synthesis in the soleus muscle (28%) and in the red (28%) and white portions (12%) of the gastrocnemius muscle compared with controls infused with only tyrosine. The increased rates of protein synthesis were due to increased incorporation of tyrosine into protein and to decreased specific activity of the free tyrosine pool. These data indicate that infusion of leucine has the potential to stimulate in vivo protein synthesis in skeletal muscles

Life and death of proteins: a case study of glucose-starved Staphylococcus aureus.

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Michalik, Stephan; Bernhardt, Jörg; Otto, Andreas; Moche, Martin; Becher, Dörte; Meyer, Hanna; Lalk, Michael; Schurmann, Claudia; Schlüter, Rabea; Kock, Holger; Gerth, Ulf; Hecker, Michael

2012-09-01

The cellular amount of proteins not only depends on synthesis but also on degradation. Here, we expand the understanding of differential protein levels by complementing synthesis data with a proteome-wide, mass spectrometry-based stable isotope labeling with amino acids in cell culture analysis of protein degradation in the human pathogen Staphylococcus aureus during glucose starvation. Monitoring protein stability profiles in a wild type and an isogenic clpP protease mutant revealed that 1) proteolysis mainly affected proteins with vegetative functions, anabolic and selected catabolic enzymes, whereas the expression of TCA cycle and gluconeogenesis enzymes increased; 2) most proteins were prone to aggregation in the clpP mutant; 3) the absence of ClpP correlated with protein denaturation and oxidative stress responses, deregulation of virulence factors and a CodY repression. We suggest that degradation of redundant, inactive proteins disintegrated from functional complexes and thereby amenable to proteolytic attack is a fundamental cellular process in all organisms to regain nutrients and guarantee protein homeostasis.

Life and Death of Proteins: A Case Study of Glucose-starved Staphylococcus aureus*

Science.gov (United States)

Michalik, Stephan; Bernhardt, Jörg; Otto, Andreas; Moche, Martin; Becher, Dörte; Meyer, Hanna; Lalk, Michael; Schurmann, Claudia; Schlüter, Rabea; Kock, Holger; Gerth, Ulf; Hecker, Michael

2012-01-01

The cellular amount of proteins not only depends on synthesis but also on degradation. Here, we expand the understanding of differential protein levels by complementing synthesis data with a proteome-wide, mass spectrometry-based stable isotope labeling with amino acids in cell culture analysis of protein degradation in the human pathogen Staphylococcus aureus during glucose starvation. Monitoring protein stability profiles in a wild type and an isogenic clpP protease mutant revealed that 1) proteolysis mainly affected proteins with vegetative functions, anabolic and selected catabolic enzymes, whereas the expression of TCA cycle and gluconeogenesis enzymes increased; 2) most proteins were prone to aggregation in the clpP mutant; 3) the absence of ClpP correlated with protein denaturation and oxidative stress responses, deregulation of virulence factors and a CodY repression. We suggest that degradation of redundant, inactive proteins disintegrated from functional complexes and thereby amenable to proteolytic attack is a fundamental cellular process in all organisms to regain nutrients and guarantee protein homeostasis. PMID:22556279

STAY-GREEN and Chlorophyll Catabolic Enzymes Interact at Light-Harvesting Complex II for Chlorophyll Detoxification during Leaf Senescence in Arabidopsis[C][W

Science.gov (United States)

Sakuraba, Yasuhito; Schelbert, Silvia; Park, So-Yon; Han, Su-Hyun; Lee, Byoung-Doo; Andrès, Céline Besagni; Kessler, Felix; Hörtensteiner, Stefan; Paek, Nam-Chon

2012-01-01

During leaf senescence, plants degrade chlorophyll to colorless linear tetrapyrroles that are stored in the vacuole of senescing cells. The early steps of chlorophyll breakdown occur in plastids. To date, five chlorophyll catabolic enzymes (CCEs), NONYELLOW COLORING1 (NYC1), NYC1-LIKE, pheophytinase, pheophorbide a oxygenase (PAO), and red chlorophyll catabolite reductase, have been identified; these enzymes catalyze the stepwise degradation of chlorophyll to a fluorescent intermediate, pFCC, which is then exported from the plastid. In addition, STAY-GREEN (SGR), Mendel’s green cotyledon gene encoding a chloroplast protein, is required for the initiation of chlorophyll breakdown in plastids. Senescence-induced SGR binds to light-harvesting complex II (LHCII), but its exact role remains elusive. Here, we show that all five CCEs also specifically interact with LHCII. In addition, SGR and CCEs interact directly or indirectly with each other at LHCII, and SGR is essential for recruiting CCEs in senescing chloroplasts. PAO, which had been attributed to the inner envelope, is found to localize in the thylakoid membrane. These data indicate a predominant role for the SGR-CCE-LHCII protein interaction in the breakdown of LHCII-located chlorophyll, likely to allow metabolic channeling of phototoxic chlorophyll breakdown intermediates upstream of nontoxic pFCC. PMID:22366162

Normal protein intake is required for body weight loss and weight maintenance, and elevated protein intake for additional preservation of resting energy expenditure and fat free mass.

Science.gov (United States)

Soenen, Stijn; Martens, Eveline A P; Hochstenbach-Waelen, Ananda; Lemmens, Sofie G T; Westerterp-Plantenga, Margriet S

2013-05-01

Energy-restricted high-protein diets (HPDs) have shown favorable results for body weight (BW) management, yet studies differ in their outcomes depending on the dietary protein content. Our objective was to determine the effects of dietary protein content on BW loss-related variables during a 6-mo energy restriction with the use of diets containing protein at the level of requirement [normal-protein diet (NPD), 0.8 g · kg BW(-1) (.) d(-1)] and above (HPD, 1.2 g · kg BW(-1) (.) d(-1)). In overweight and obese participants (24 men and 48 women), BW, body composition, and metabolic responses were assessed before and after subsequent energy intakes of 100, 33, and 67% of the original individual daily energy requirements. Protein intake was consistent in the NPD (0.8 ± 0.3 g · kg BW(-1) (.) d(-1)) and HPD (1.2 ± 0.3 g · kg BW(-1) (.) d(-1)) groups throughout the study (P body fat mass similarly decreased in the NPD and HPD groups (P initial sparing effect of FFM and lowering of DBP.

Expression of the helix-loop-helix protein inhibitor of DNA binding-1 (ID-1) is activated by all-trans retinoic acid in normal human keratinocytes

International Nuclear Information System (INIS)

Villano, C.M.; White, L.A.

2006-01-01

The ID (inhibitor of differentiation or DNA binding) helix-loop-helix proteins are important mediators of cellular differentiation and proliferation in a variety of cell types through regulation of gene expression. Overexpression of the ID proteins in normal human keratinocytes results in extension of culture lifespan, indicating that these proteins are important for epidermal differentiation. Our hypothesis is that the ID proteins are targets of the retinoic acid signaling pathway in keratinocytes. Retinoids, vitamin A analogues, are powerful regulators of cell growth and differentiation and are widely used in the prevention and treatment of a variety of cancers in humans. Furthermore, retinoic acid is necessary for the maintenance of epithelial differentiation and demonstrates an inhibitory action on skin carcinogenesis. We examined the effect of all-trans retinoic acid on expression of ID-1, -2, -3, and -4 in normal human keratinocytes and found that exposure of these cells to all-trans retinoic acid causes an increase in both ID-1 and ID-3 gene expression. Furthermore, our data show that this increase is mediated by increased transcription involving several cis-acting elements in the distal portion of the promoter, including a CREB-binding site, an Egr1 element, and an YY1 site. These data demonstrate that the ID proteins are direct targets of the retinoic acid signaling pathway. Given the importance of the ID proteins to epidermal differentiation, these results suggest that IDs may be mediating some of the effects of all-trans retinoic acid in normal human keratinocytes

The Alzheimer's Disease-Associated Amyloid β-Protein Is an Antimicrobial Peptide

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Soscia, Stephanie J.; Kirby, James E.; Washicosky, Kevin J.; Tucker, Stephanie M.; Ingelsson, Martin; Hyman, Bradley; Burton, Mark A.; Goldstein, Lee E.; Duong, Scott; Tanzi, Rudolph E.; Moir, Robert D.

2010-01-01

Background The amyloid β-protein (Aβ) is believed to be the key mediator of Alzheimer's disease (AD) pathology. Aβ is most often characterized as an incidental catabolic byproduct that lacks a normal physiological role. However, Aβ has been shown to be a specific ligand for a number of different receptors and other molecules, transported by complex trafficking pathways, modulated in response to a variety of environmental stressors, and able to induce pro-inflammatory activities. Methodology/Principal Findings Here, we provide data supporting an in vivo function for Aβ as an antimicrobial peptide (AMP). Experiments used established in vitro assays to compare antimicrobial activities of Aβ and LL-37, an archetypical human AMP. Findings reveal that Aβ exerts antimicrobial activity against eight common and clinically relevant microorganisms with a potency equivalent to, and in some cases greater than, LL-37. Furthermore, we show that AD whole brain homogenates have significantly higher antimicrobial activity than aged matched non-AD samples and that AMP action correlates with tissue Aβ levels. Consistent with Aβ-mediated activity, the increased antimicrobial action was ablated by immunodepletion of AD brain homogenates with anti-Aβ antibodies. Conclusions/Significance Our findings suggest Aβ is a hitherto unrecognized AMP that may normally function in the innate immune system. This finding stands in stark contrast to current models of Aβ-mediated pathology and has important implications for ongoing and future AD treatment strategies. PMID:20209079

Metabolic reconstructions identify plant 3-methylglutaconyl-CoA hydratase that is crucial for branched-chain amino acid catabolism in mitochondria

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The proteinogenic branched-chain amino acids (BCAAs) leucine, isoleucine, and valine are essential nutrients for mammals. In plants, they double as alternative energy sources when carbohydrates become limiting, the catabolism of BCAAs providing electrons to the respiratory chain and intermediates...

Correlation Between Placental Matrix Metalloproteinase 9 and Tumor Necrosis Factor-α Protein Expression Throughout Gestation in Normal Human Pregnancy.

Science.gov (United States)

Basu, Jayasri; Agamasu, Enyonam; Bendek, Bolek; Salafia, Carolyn M; Mishra, Aruna; Lopez, Julia Vasquez; Kroes, Jessica; Dragich, Sharon Claire; Thakur, Ashley; Mikhail, Magdy

2018-04-01

Matrix metalloproteinases (MMPs), specifically MMP-9 plays a role in human placentation. The enzyme confers an invasive ability to cytotrophoblasts and degrades the endometrial matrix as the cells infiltrate the decidua to keep up with placental growth. Since tumor necrosis factor-α (TNF-α) can induce the synthesis of MMP-9, we investigated the patterns of changes in and correlation between placental villous MMP-9 and TNF-α expressions throughout normal human gestation. Placentas were obtained from 179 normal pregnant women who underwent elective abortion or term delivery. Chorionic villi isolated from placental samples were grouped as first, second, and third trimester (7 0/7 -13 0/7 , 13 1/7 -23 6/7 , and 37 0/7 -42 4/7 weeks, respectively). Chorionic villous TNF-α and MMP-9 proteins were assayed using enzyme immunoassay kits. There were significant differences in MMP-9 and TNF-α protein expressions among the trimester groups ( P = .001). The MMP-9 protein increased progressively with an increase in gestational age (GA), but TNF-α peaked in the second trimester. Within each trimester group, we searched for the effects of variation of GA in days on the 2 variables. A significant positive correlation between MMP-9 and GA was noted in the first trimester ( r = 0.364, P = .005). No other comparisons were significant. When GA was controlled for, partial correlation revealed a significant positive correlation between TNF-α and MMP-9 only in the second trimester ( r = 0.300, P = .018). We hypothesize that the TNF-α peak and the positive correlation between TNF-α and MMP-9 in the second trimester of normal human gestation could contribute toward a successful pregnancy outcome.

In vitro biosynthesis of complement protein D

International Nuclear Information System (INIS)

Barnum, S.R.

1985-01-01

The aim of this study was twofold: to determine site(s) of complement protein D biosynthesis and to examine D biosynthesis with respect to the kinetics of D secretion, the post-translational modification of D and the tissue-specific differences in D secretion and processing. Antigenic D was detected in the culture supernatants of two cell lines, U937 and HepG2, and adherent blood monocytes by a solid-phase radioimmunoassay. D secreted by U937 cells was hemolytically active with a specific activity comparable to D in serum. De novo synthesis of D by U937 cells was demonstrated with the use of cycloheximide. Biosynthetic labeling using 35 S labeled methionine or cysteine, followed by immunoprecipitation demonstrated a single d band intra- and extra-cellularly in all three cell types as analyzed by SDS-PAGE and auto-radiography. Elevated serum D levels in individuals with IgA nephropathy led to studies on the D levels in serum and urine of individuals with chronic renal failure and an individual with Fanconi's syndrome. The former group had elevated serum D levels, compared to normals, and insignificant levels of D in their urine while the patient with Fanconi's syndrome had normal serum D levels but markedly elevated urinary D levels. These studies demonstrate that the monocyte and hepatocyte are both sites of D synthesis and that there are no apparent differences in the secretion rates and processing of D produced by these cell types. The results also suggest that D is not synthesized or secreted as a precursor molecule. Additionally, these studies suggest that the kidney is a major site of D catabolism

Results from the European Prospective Investigation into Cancer and Nutrition Link Vitamin B6 Catabolism and Lung Cancer Risk.

NARCIS (Netherlands)

Zuo, Hui; Ueland, Per M; Midttun, Øivind; Vollset, Stein E; Tell, Grethe S; Theofylaktopoulou, Despoina; Travis, Ruth C; Boutron-Ruault, Marie-Christine; Fournier, Agnès; Severi, Gianluca; Kvaskoff, Marina; Boeing, Heiner; Bergmann, Manuela M; Fortner, Renée T; Kaaks, Rudolf; Trichopoulou, Antonia; Kotanidou, Anastasia; Lagiou, Pagona; Palli, Domenico; Sieri, Sabina; Panico, Salvatore; Bueno-de-Mesquita, H Bas; Peeters, Petra H; Grankvist, Kjell; Johansson, Mikael; Agudo, Antonio; Garcia, Jose Ramon Quiros; Larranaga, Nerea; Sanchez, Maria-Jose; Chirlaque, Maria Dolores; Ardanaz, Eva; Chuang, Shu-Chun; Gallo, Valentina; Brennan, Paul; Johansson, Mattias; Ulvik, Arve

2018-01-01

Circulating pyridoxal-5'-phosphate (PLP) has been linked to lung cancer risk. The PAr index, defined as the ratio 4-pyridoxic acid/(pyridoxal + PLP), reflects increased vitamin B6 catabolism during inflammation. PAr has been defined as a marker of lung cancer risk in a prospective cohort study, but

Protein-Energy Wasting and Mortality in Chronic Kidney Disease

Directory of Open Access Journals (Sweden)

Ezio Gianetta

2011-05-01

Full Text Available Protein-energy wasting (PEW is common in patients with chronic kidney disease (CKD and is associated with an increased death risk from cardiovascular diseases. However, while even minor renal dysfunction is an independent predictor of adverse cardiovascular prognosis, PEW becomes clinically manifest at an advanced stage, early before or during the dialytic stage. Mechanisms causing loss of muscle protein and fat are complex and not always associated with anorexia, but are linked to several abnormalities that stimulate protein degradation and/or decrease protein synthesis. In addition, data from experimental CKD indicate that uremia specifically blunts the regenerative potential in skeletal muscle, by acting on muscle stem cells. In this discussion recent findings regarding the mechanisms responsible for malnutrition and the increase in cardiovascular risk in CKD patients are discussed. During the course of CKD, the loss of kidney excretory and metabolic functions proceed together with the activation of pathways of endothelial damage, inflammation, acidosis, alterations in insulin signaling and anorexia which are likely to orchestrate net protein catabolism and the PEW syndrome.

Skeletal muscle myosin heavy chain isoform content in relation to gonadal hormones and anabolic-catabolic balance in trained and untrained men.

Science.gov (United States)

Grandys, Marcin; Majerczak, Joanna; Karasinski, Janusz; Kulpa, Jan; Zoladz, Jerzy A

2012-12-01

Gonadal hormones and anabolic-catabolic hormone balance have potent influence on skeletal muscle tissue, but little is known about their action with regard to myosin heavy chain (MHC) transformation in humans. We investigated the relationship between skeletal muscle MHC isoform content in the vastus lateralis muscle and basal testosterone (T) concentration in 3 groups of subjects: endurance trained (E), sprint/strength trained (S), and untrained (U) young men. We have also determined basal sex hormone-binding globulin and cortisol (C) concentrations in untrained subjects to examine the relationship between MHC composition and the anabolic-catabolic hormone balance. Moreover, basal free testosterone (fT) and bioavailable testosterone (bio-T) concentrations were calculated for this subgroup. Despite significant differences in MHC isoform content (69.4 ± 2.39%, 61.4 ± 8.04%, and 37.5 ± 13.80% of MHC-2 for groups S, U, and E, respectively, Kruskal-Wallis: H = 18.58, p 0.5). We have also found that in the U group, type 2 MHC in the vastus lateralis muscle is positively correlated with basal fT:C ratio (r = 0.63, p = 0.01). It is concluded that the differences in the training history and training specificity can be distinguished with regard to the MHC composition but not with regard to the basal T concentration. Simultaneously, it has been shown that MHC isoform content in human vastus lateralis muscle may be related to basal anabolic-catabolic hormone balance, and this hypothesis needs further investigation.

Effect of passive smoking on the levels of pregnancy associated plasma protein-A in normal rats

International Nuclear Information System (INIS)

Naveed, A.K.; Rahim, A.; Malik, M.S.

2010-01-01

To measure the levels of pregnancy associated plasma protein- A (PAPPA-A) in normal rats exposed to cigarette smoke. Sixty albino rats of Sprague- Dawley strain weighing 200-250 gm, divided into two groups. Both the groups were kept in identical chambers. One group of 30 rats was further exposed to passive cigarette smoke for 4 weeks. No increase was observed in the levels of serum PAPP-A of both the groups: Passive smokers and not exposed to passive smoking i.e. P > 0.05. Smoking does not increase the levels of PAPP-A. (author)

Results from the European prospective investigation into cancer and nutrition link vitamin B6 catabolism and lung cancer risk

NARCIS (Netherlands)

Zuo, Hui; Ueland, Per Magne; Midttun, Øivind; Vollset, Stein Emil; Tell, Grethe S.; Theofylaktopoulou, Despoina; Travis, Ruth C.; Boutron-Ruault, Marie Christine; Fournier, Agnès; Severi, Gianluca; Kvaskoff, Marina; Boeing, Heiner; Bergmann, Manuela M.; Turzanski-Fortner, Renée; Kaaks, Rudolf; Trichopoulou, Antonia; Kotanidou, Anastasia; Lagiou, Pagona; Palli, Domenico; Sieri, Sabina; Panico, Salvatore; Bueno-De-Mesquita, H. Bas; Peeters, Petra H.; Grankvist, Kjell; Johansson, Mikael; Agudo, Antonio; Garcia, Jose Ramon Quiros; Larranaga, Nerea; Sanchez, Maria-Jose; Chirlaque, Maria-Dolores; Ardanaz, Eva; Chuang, Shu Chun; Gallo, Valentina; Brennan, Paul; Johansson, Mattias; Ulvik, Arve

2018-01-01

Circulating pyridoxal-5′-phosphate (PLP) has been linked to lung cancer risk. The PAr index, defined as the ratio 4-pyridoxic acid/(pyridoxal + PLP), reflects increased vitamin B6 catabolism during inflammation. PAr has been defined as a marker of lung cancer risk in a prospective cohort study, but

Nutritional Status of Maintenance Dialysis Patients: Low Lean Body Mass Index and Obesity Are Common, Protein-Energy Wasting Is Uncommon.

Directory of Open Access Journals (Sweden)

Mette Koefoed

Full Text Available Maintenance dialysis patients are at increased risk of abnormal nutritional status due to numerous causative factors, both nutritional and non-nutritional. The present study assessed the current prevalence of protein-energy wasting, low lean body mass index and obesity in maintenance dialysis patients, and compared different methods of nutritional assessment.In a cross-sectional study conducted in 2014 at Roskilde Hospital, Denmark, we performed anthropometry (body weight, skinfolds, mid-arm, waist, and hip circumferences, and determined plasma albumin and normalized protein catabolic rate in order to assess the prevalence of protein-energy wasting, low lean body mass index and obesity in these patients.Seventy-nine eligible maintenance dialysis patients participated. The prevalence of protein-energy wasted patients was 4% (95% CI: 2-12 as assessed by the coexistence of low lean body mass index and low fat mass index. Low lean body mass index was seen in 32% (95% CI: 22-44. Obesity prevalence as assessed from fat mass index was 43% (95% CI: 32-55. Coexistence of low lean body mass index and obesity was seen in 10% (95% CI: 5-19. The prevalence of protein-energy wasting and obesity varied considerably, depending on nutritional assessment methodology.Our data indicate that protein-energy wasting is uncommon, whereas low lean body mass index and obesity are frequent conditions among patients in maintenance dialysis. A focus on how to increase and preserve lean body mass in dialysis patients is suggested in the future. In order to clearly distinguish between shortage, sufficiency and abundance of protein and/or fat deposits in maintenance dialysis patients, we suggest the simple measurements of lean body mass index and fat mass index.

Nutritional Status of Maintenance Dialysis Patients: Low Lean Body Mass Index and Obesity Are Common, Protein-Energy Wasting Is Uncommon.

Science.gov (United States)

Koefoed, Mette; Kromann, Charles Boy; Juliussen, Sophie Ryberg; Hvidtfeldt, Danni; Ekelund, Bo; Frandsen, Niels Erik; Marckmann, Peter

2016-01-01

Maintenance dialysis patients are at increased risk of abnormal nutritional status due to numerous causative factors, both nutritional and non-nutritional. The present study assessed the current prevalence of protein-energy wasting, low lean body mass index and obesity in maintenance dialysis patients, and compared different methods of nutritional assessment. In a cross-sectional study conducted in 2014 at Roskilde Hospital, Denmark, we performed anthropometry (body weight, skinfolds, mid-arm, waist, and hip circumferences), and determined plasma albumin and normalized protein catabolic rate in order to assess the prevalence of protein-energy wasting, low lean body mass index and obesity in these patients. Seventy-nine eligible maintenance dialysis patients participated. The prevalence of protein-energy wasted patients was 4% (95% CI: 2-12) as assessed by the coexistence of low lean body mass index and low fat mass index. Low lean body mass index was seen in 32% (95% CI: 22-44). Obesity prevalence as assessed from fat mass index was 43% (95% CI: 32-55). Coexistence of low lean body mass index and obesity was seen in 10% (95% CI: 5-19). The prevalence of protein-energy wasting and obesity varied considerably, depending on nutritional assessment methodology. Our data indicate that protein-energy wasting is uncommon, whereas low lean body mass index and obesity are frequent conditions among patients in maintenance dialysis. A focus on how to increase and preserve lean body mass in dialysis patients is suggested in the future. In order to clearly distinguish between shortage, sufficiency and abundance of protein and/or fat deposits in maintenance dialysis patients, we suggest the simple measurements of lean body mass index and fat mass index.

Metabolic profiling of hypoxic cells revealed a catabolic signature required for cell survival.

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Christian Frezza

Full Text Available Hypoxia is one of the features of poorly vascularised areas of solid tumours but cancer cells can survive in these areas despite the low oxygen tension. The adaptation to hypoxia requires both biochemical and genetic responses that culminate in a metabolic rearrangement to counter-balance the decrease in energy supply from mitochondrial respiration. The understanding of metabolic adaptations under hypoxia could reveal novel pathways that, if targeted, would lead to specific death of hypoxic regions. In this study, we developed biochemical and metabolomic analyses to assess the effects of hypoxia on cellular metabolism of HCT116 cancer cell line. We utilized an oxygen fluorescent probe in anaerobic cuvettes to study oxygen consumption rates under hypoxic conditions without the need to re-oxygenate the cells and demonstrated that hypoxic cells can maintain active, though diminished, oxidative phosphorylation even at 1% oxygen. These results were further supported by in situ microscopy analysis of mitochondrial NADH oxidation under hypoxia. We then used metabolomic methodologies, utilizing liquid chromatography-mass spectrometry (LC-MS, to determine the metabolic profile of hypoxic cells. This approach revealed the importance of synchronized and regulated catabolism as a mechanism of adaptation to bioenergetic stress. We then confirmed the presence of autophagy under hypoxic conditions and demonstrated that the inhibition of this catabolic process dramatically reduced the ATP levels in hypoxic cells and stimulated hypoxia-induced cell death. These results suggest that under hypoxia, autophagy is required to support ATP production, in addition to glycolysis, and that the inhibition of autophagy might be used to selectively target hypoxic regions of tumours, the most notoriously resistant areas of solid tumours.

Influence of the glutamic acid content of the diet on the catabolic rate of labelled glutamic acid in rats. 2

International Nuclear Information System (INIS)

Wilke, A.; Simon, O.; Bergner, H.

1984-01-01

40 rats with a body weight of 100 g received 7 semisynthetic diets with different contents of glutamic acid and one diet contained whole-egg. A L-amino acid mixture corresponding to the pattern of egg protein was the protein source of the semisynthetic diets. Glutamic acid was supplemented succesively from 0 to 58 mol-% of the total amino acid content. On the 8th day of the experimental feeding the animals were labelled by subcutaneous injection of 14 C-glutamic acid. Subsequently the CO 2 and the 14 CO 2 excretion were measured for 24 hours. In this period 64 to 68 % of the injected radioactivity were recovered as 14 CO 2 . The curve pattern of 14 CO 2 excretion indicates two different processes of 14 CO 2 formation. One characterizing the direct degradation of glutamic acid to CO 2 with a high rate constant and a second one with a lower rate constant characterizing the 14 CO 2 formation via metabolites of glutamic acid. 77 % of the total 14 CO 2 excretion in 24 hours resulted from the direct oxidation of glutamic acid and 23 % from the oxidation of intermediates. When 14 CO 2 formation was measured 10 to 24 hours after injection of 14 C-glutamic acid a positive correlation to the content of glutamic acid in the diet was observed. The intestinal tissue contributes considerably to the catabolization of glutamic acid, however, there seems to exist an upper limit for this capacity. (author)

Skin Barrier Development Depends on CGI-58 Protein Expression during Late-Stage Keratinocyte Differentiation

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Grond, Susanne; Radner, Franz P.W.; Eichmann, Thomas O.; Kolb, Dagmar; Grabner, Gernot F.; Wolinski, Heimo; Gruber, Robert; Hofer, Peter; Heier, Christoph; Schauer, Silvia; Rülicke, Thomas; Hoefler, Gerald; Schmuth, Matthias; Elias, Peter M.; Lass, Achim; Zechner, Rudolf; Haemmerle, Guenter

2017-01-01

Adipose triglyceride lipase (ATGL) and its coactivator comparative gene identification-58 (CGI-58) are limiting in cellular triglyceride catabolism. Although ATGL deficiency is compatible with normal skin development, mice globally lacking CGI-58 die postnatally and exhibit a severe epidermal permeability barrier defect, which may originate from epidermal and/or peripheral changes in lipid and energy metabolism. Here, we show that epidermis-specific disruption of CGI-58 is sufficient to provoke a defect in the formation of a functional corneocyte lipid envelope linked to impaired ω-O-acylceramide synthesis. As a result, epidermis-specific CGI-58-deficient mice show severe skin dysfunction, arguing for a tissue autonomous cause of disease development. Defective skin permeability barrier formation in global CGI-58-deficient mice could be reversed via transgenic restoration of CGI-58 expression in differentiated but not basal keratinocytes suggesting that CGI-58 is essential for lipid metabolism in suprabasal epidermal layers. The compatibility of ATGL deficiency with normal epidermal function indicated that CGI-58 may stimulate an epidermal triglyceride lipase beyond ATGL required for the adequate provision of fatty acids as a substrate for ω-O-acylceramide synthesis. Pharmacological inhibition of ATGL enzyme activity similarly reduced triglyceride-hydrolytic activities in wild-type and CGI-58 overexpressing epidermis implicating that CGI-58 participates in ω-O-acylceramide biogenesis independent of its role as a coactivator of epidermal triglyceride catabolism. PMID:27725204

Identification of autophagosome-associated proteins and regulators by quantitative proteomic analysis and genetic screens

DEFF Research Database (Denmark)

Dengjel, Jörn; Høyer-Hansen, Maria; Nielsen, Maria

2012-01-01

Autophagy is one of the major intracellular catabolic pathways, but little is known about the composition of autophagosomes. To study the associated proteins, we isolated autophagosomes from human breast cancer cells using two different biochemical methods and three stimulus types: amino acid dep...... regulators of autophagy, including subunits of the retromer complex. The combined spatiotemporal proteomic and genetic data sets presented here provide a basis for further characterization of autophagosome biogenesis and cargo selection....

Acrolein-Exposed Normal Human Lung Fibroblasts in Vitro: Cellular Senescence, Enhanced Telomere Erosion, and Degradation of Werner’s Syndrome Protein

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Jang, Jun-Ho; Bruse, Shannon; Huneidi, Salam; Schrader, Ronald M.; Monick, Martha M.; Lin, Yong; Carter, A. Brent; Klingelhutz, Aloysius J.

2014-01-01

Background: Acrolein is a ubiquitous environmental hazard to human health. Acrolein has been reported to activate the DNA damage response and induce apoptosis. However, little is known about the effects of acrolein on cellular senescence. Objectives: We examined whether acrolein induces cellular senescence in cultured normal human lung fibroblasts (NHLF). Methods: We cultured NHLF in the presence or absence of acrolein and determined the effects of acrolein on cell proliferative capacity, senescence-associated β-galactosidase activity, the known senescence-inducing pathways (e.g., p53, p21), and telomere length. Results: We found that acrolein induced cellular senescence by increasing both p53 and p21. The knockdown of p53 mediated by small interfering RNA (siRNA) attenuated acrolein-induced cellular senescence. Acrolein decreased Werner’s syndrome protein (WRN), a member of the RecQ helicase family involved in DNA repair and telomere maintenance. Acrolein-induced down-regulation of WRN protein was rescued by p53 knockdown or proteasome inhibition. Finally, we found that acrolein accelerated p53-mediated telomere shortening. Conclusions: These results suggest that acrolein induces p53-mediated cellular senescence accompanied by enhanced telomere attrition and WRN protein down-regulation. Citation: Jang JH, Bruse S, Huneidi S, Schrader RM, Monick MM, Lin Y, Carter AB, Klingelhutz AJ, Nyunoya T. 2014. Acrolein-exposed normal human lung fibroblasts in vitro: cellular senescence, enhanced telomere erosion, and degradation of Werner’s syndrome protein. Environ Health Perspect 122:955–962; http://dx.doi.org/10.1289/ehp.1306911 PMID:24747221

Differential expression and processing of transforming growth factor beta induced protein (TGFBIp) in the normal human cornea during postnatal development and aging

DEFF Research Database (Denmark)

Karring, Henrik; Runager, Kasper; Valnickova, Zuzana

2010-01-01

Transforming growth factor beta induced protein (TGFBIp, also named keratoepithelin) is an extracellular matrix protein abundant in the cornea. The purpose of this study was to determine the expression and processing of TGFBIp in the normal human cornea during postnatal development and aging...... trimming events from the N-terminus of mature TGFBIp generate TGFBIp isoforms which form a similar "zig-zag" pattern when separated by 2-D polyacrylamide gel electrophoresis (PAGE). This study shows that in humans TGFBIp is more abundant in mature corneas than in the developing cornea...... and that the processing of TGFBIp changes during postnatal development of the cornea. In addition, TGFBIp appears to be degraded in a highly orchestrated manner in the normal human cornea with the resulting C-terminal fragments being retained in the cornea. The age-related changes in the expression and processing...

Nucleotide sequence, organization and characterization of the (halo)aromatic acid catabolic plasmid pA81 from Achromobacter xylosoxidans A8

Czech Academy of Sciences Publication Activity Database

Jenčová, V.; Strnad, Hynek; Chodora, Zdeněk; Ulbrich, Pavel; Vlček, Čestmír; Hickey, W. J.; Pačes, Václav

2008-01-01

Roč. 159, č. 2 (2008), s. 118-127 ISSN 0923-2508 R&D Projects: GA MŠk(CZ) 1M0520 Institutional research plan: CEZ:AV0Z50520514 Keywords : megaplasmid * haloaromatic acid * catabolism Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.055, year: 2008

Heme synthesis in normal mouse liver and mouse liver tumors

International Nuclear Information System (INIS)

Stout, D.L.; Becker, F.F.

1990-01-01

Hepatic cancers from mice and rats demonstrate decreased levels of delta-aminolevulinic acid synthase, the rate-limiting enzyme in the heme synthetic pathway, and increased heme oxygenase, the heme-catabolizing enzyme. These findings suggest that diminution of P-450, b5, and catalase in these lesions may result from a heme supply that is limited by decreased heme synthesis and increased heme catabolism. Heme synthesis was measured in mouse liver tumors (MLT) and adjacent tumor-free lobes (BKG) by administering the radiolabeled heme precursors 55 FeCl3 and [2- 14 C]glycine and subsequently extracting the heme for determination of specific activity. Despite reduced delta-aminolevulinic acid synthase activity in MLT, both tissues incorporated [2-14C]glycine into heme at similar rates. At early time points, heme extracted from MLT contained less 55Fe than that from BKG. This was attributed to the findings that MLT took up 55Fe at a slower rate than BKG and had larger iron stores than BKG. The amount of heme per milligram of protein was also similar in both tissues. These findings militate against the hypothesis that diminished hemoprotein levels in MLT result from limited availability of heme. It is probable, therefore, that decreased hemoprotein levels in hepatic tumors are linked to a general program of dedifferentiation associated with the cancer phenotype. Diminution of hemoprotein in MLT may result in a relatively increased intracellular heme pool. delta-Aminolevulinic acid synthase and heme oxygenase are, respectively, negatively and positively regulated by heme. Thus, their alteration in MLT may be due to the regulatory influences of the heme pool

Development of a radioimmunoassay for pregnancy-associated plasma protein A and establishment of normal levels in the first trimester of pregnancy

Energy Technology Data Exchange (ETDEWEB)

Anthony, F; Masson, G M; Wood, P J [Southampton Univ. (UK)

1983-01-01

An accelerated double antibody method has been developed for the radioimmunoassay of pregnancy-associated plasma protein A (PAPP-A) in serum. The workable range for the assay was 0.4-1.8 mg/l of serum. PAPP-A levels were determined in single serum samples from 110 women with prospective normal pregnancies of between 7 and 14 weeks' gestation. The level of pregnancy specific ..beta../sub 1/ glycoprotein (SP/sub 1/) was also measured in these samples and normal ranges for PAPP-P and SP/sub 1/ were constructed from the results obtained.

Development of a radioimmunoassay for pregnancy-associated plasma protein A and establishment of normal levels in the first trimester of pregnancy

Energy Technology Data Exchange (ETDEWEB)

Anthony, F; Masson, G M; Wood, P J [Southampton Univ. (UK)

1983-01-01

An accelerated double antibody method has been developed for the radioimmunoassay of pregnancy-associated plasma protein A (PAPP-A) in serum. The workable range for the assay was 0.04-1.8 mg/l of serum. PAPP-A levels were determined in single serum samples from 110 women with prospective normal pregnancies of between 7 and 14 weeks' gestation. The level of pregnancy specific ..beta../sub 1/ glycoprotein (SP/sub 1/) was also measured in these samples and normal ranges for PAPP-A and SP/sub 1/ were constructed from the results obtained.

Development of a radioimmunoassay for pregnancy-associated plasma protein A and establishment of normal levels in the first trimester of pregnancy

International Nuclear Information System (INIS)

Anthony, F.; Masson, G.M.; Wood, P.J.

1983-01-01

An accelerated double antibody method has been developed for the radioimmunoassay of pregnancy-associated plasma protein A (PAPP-A) in serum. The workable range for the assay was 0.4-1.8 mg/l of serum. PAPP-A levels were determined in single serum samples from 110 women with prospective normal pregnancies of between 7 and 14 weeks' gestation. The level of pregnancy specific #betta# 1 glycoprotein (SP 1 ) was also measured in these samples and normal ranges for PAPP-P and SP 1 were constructed from the results obtained. (author)

Presence or absence of carbohydrates and the proportion of fat in a high-protein diet affect appetite suppression but not energy expenditure in normal-weight human subjects fed in energy balance.

Science.gov (United States)

Veldhorst, Margriet A B; Westerterp, Klaas R; van Vught, Anneke J A H; Westerterp-Plantenga, Margriet S

2010-11-01

Two types of relatively high-protein diets, with a normal or low proportion of carbohydrates, have been shown effective for weight loss. The objective was to assess the significance of the presence or absence of carbohydrates and the proportion of fat in high-protein diets for affecting appetite suppression, energy expenditure, and fat oxidation in normal-weight subjects in energy balance. Subjects (aged 23 (sd 3) years and BMI 22·0 (sd 1·9) kg/m2) were stratified in two groups. Each was offered two diets in a randomised cross-over design: group 1 (n 22) - normal protein (NP; 10, 60 and 30 % energy (En%) from protein, carbohydrate and fat), high protein (HP; 30, 40 and 30 En%); group 2 (n 23) - normal protein (NP-g; 10, 60 and 30 En%), high protein, carbohydrate-free (HP-0C; 30, 0 and 70 En%) for 2 d; NP-g and HP-0C were preceded by glycogen-lowering exercise (day 1). Appetite was measured throughout day 2 using visual analogue scales (VAS). Energy expenditure (EE) and substrate oxidation (respiratory quotient; RQ) were measured in a respiration chamber (08.00 hours on day 2 until 07.30 hours on day 3). Fasting plasma β-hydroxybutyrate (BHB) concentration was measured (day 3). NP-g and NP did not differ in hunger, EE, RQ and BHB. HP-0C and HP v. NP-g and NP, respectively, were lower in hunger (P fat oxidation were higher on a high-protein diet without than with carbohydrates exchanged for fat. Energy expenditure was not affected by the carbohydrate content of a high-protein diet.

Protein metabolism in obese patients during very low-calorie mixed diets containing different amounts of proteins and carbohydrates.

Science.gov (United States)

Pasquali, R; Casimirri, F; Melchionda, N

1987-12-01

To assess long-term nitrogen sparing capacity of very low-calorie mixed diets, we administered two isoenergetic (2092KJ) liquid formula regimens of different composition for 8 weeks to two matched groups of massively obese patients (group 1: proteins 60 g, carbohydrate 54 g; group 2: proteins 41 g, carbohydrates 81 g). Weight loss was similar in both groups. Daily nitrogen balance (g) during the second month resulted more a negative in group 2 with respect to group 1. However, within the groups individual nitrogen sparing capacity varied markedly; only a few in group 1 and one in group 2 were able to attain nitrogen equilibrium throughout the study. Daily urine excretion of 3-methylhistidine fell significantly in group 1 but did not change in group 2. Unlike total proteins, albumins, and transferrin, serum levels of retinol-binding protein, thyroxin-binding globulin, and complement-C3 fell significantly in both groups but per cent variations of complement-C3 were more pronounced in the first group. Prealbumin levels fell persistently in group 1 and transiently in group 2. The results indicate that even with this type of diet an adequate amount of dietary protein represents the most important factor in minimizing whole body protein catabolism during long-term semistarvation in massively obese patients. Moreover, they confirm the possible role of dietary carbohydrates in the regulation of some visceral protein metabolism.

Evolved osmotolerant Escherichia coli mutants frequently exhibit defective N-acetylglucosamine catabolism and point mutations in cell shape-regulating protein MreB.

Science.gov (United States)

Winkler, James D; Garcia, Carlos; Olson, Michelle; Callaway, Emily; Kao, Katy C

2014-06-01

Biocatalyst robustness toward stresses imposed during fermentation is important for efficient bio-based production. Osmotic stress, imposed by high osmolyte concentrations or dense populations, can significantly impact growth and productivity. In order to better understand the osmotic stress tolerance phenotype, we evolved sexual (capable of in situ DNA exchange) and asexual Escherichia coli strains under sodium chloride (NaCl) stress. All isolates had significantly improved growth under selection and could grow in up to 0.80 M (47 g/liter) NaCl, a concentration that completely inhibits the growth of the unevolved parental strains. Whole genome resequencing revealed frequent mutations in genes controlling N-acetylglucosamine catabolism (nagC, nagA), cell shape (mrdA, mreB), osmoprotectant uptake (proV), and motility (fimA). Possible epistatic interactions between nagC, nagA, fimA, and proV deletions were also detected when reconstructed as defined mutations. Biofilm formation under osmotic stress was found to be decreased in most mutant isolates, coupled with perturbations in indole secretion. Transcriptional analysis also revealed significant changes in ompACGL porin expression and increased transcription of sulfonate uptake systems in the evolved mutants. These findings expand our current knowledge of the osmotic stress phenotype and will be useful for the rational engineering of osmotic tolerance into industrial strains in the future. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Copper suppresses abscisic acid catabolism and catalase activity, and inhibits seed germination of rice.

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Ye, Nenghui; Li, Haoxuan; Zhu, Guohui; Liu, Yinggao; Liu, Rui; Xu, Weifeng; Jing, Yu; Peng, Xinxiang; Zhang, Jianhua

2014-11-01

Although copper (Cu) is an essential micronutrient for plants, a slight excess of Cu in soil can be harmful to plants. Unfortunately, Cu contamination is a growing problem all over the world due to human activities, and poses a soil stress to plant development. As one of the most important biological processes, seed germination is sensitive to Cu stress. However, little is known about the mechanism of Cu-induced inhibition of seed germination. In the present study, we investigated the relationship between Cu and ABA which is the predominant regulator of seed germination. Cu at a concentration of 30 µM effectively inhibited germination of rice caryopsis. ABA content in germinating seeds under copper stress was also higher than that under control conditions. Quantitative real-time PCR (qRT-PCR) revealed that Cu treatment reduced the expression of OsABA8ox2, a key gene of ABA catabolism in rice seeds. In addition, both malondialdehyde (MDA) and H2O2 contents were increased by Cu stress in the germinating seeds. Antioxidant enzyme assays revealed that only catalase activity was reduced by excess Cu, which was consistent with the mRNA profile of OsCATa during seed germination under Cu stress. Together, our results demonstrate that suppression of ABA catabolism and catalase (CAT) activity by excess Cu leads to the inhibition of seed germination of rice. © The Author 2014. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

PTP1B antisense oligonucleotide lowers PTP1B protein, normalizes blood glucose, and improves insulin sensitivity in diabetic mice

Science.gov (United States)

Zinker, Bradley A.; Rondinone, Cristina M.; Trevillyan, James M.; Gum, Rebecca J.; Clampit, Jill E.; Waring, Jeffrey F.; Xie, Nancy; Wilcox, Denise; Jacobson, Peer; Frost, Leigh; Kroeger, Paul E.; Reilly, Regina M.; Koterski, Sandra; Opgenorth, Terry J.; Ulrich, Roger G.; Crosby, Seth; Butler, Madeline; Murray, Susan F.; McKay, Robert A.; Bhanot, Sanjay; Monia, Brett P.; Jirousek, Michael R.

2002-01-01

The role of protein-tyrosine phosphatase 1B (PTP1B) in diabetes was investigated using an antisense oligonucleotide in ob/ob and db/db mice. PTP1B antisense oligonucleotide treatment normalized plasma glucose levels, postprandial glucose excursion, and HbA1C. Hyperinsulinemia was also reduced with improved insulin sensitivity. PTP1B protein and mRNA were reduced in liver and fat with no effect in skeletal muscle. Insulin signaling proteins, insulin receptor substrate 2 and phosphatidylinositol 3 (PI3)-kinase regulatory subunit p50α, were increased and PI3-kinase p85α expression was decreased in liver and fat. These changes in protein expression correlated with increased insulin-stimulated protein kinase B phosphorylation. The expression of liver gluconeogenic enzymes, phosphoenolpyruvate carboxykinase, and fructose-1,6-bisphosphatase was also down-regulated. These findings suggest that PTP1B modulates insulin signaling in liver and fat, and that therapeutic modalities targeting PTP1B inhibition may have clinical benefit in type 2 diabetes. PMID:12169659

Characterization of Agronomy, Grain Physicochemical Quality, and Nutritional Property of High-Lysine 35R Transgenic Rice with Simultaneous Modification of Lysine Biosynthesis and Catabolism.

Science.gov (United States)

Yang, Qingqing; Wu, Hongyu; Li, Qianfeng; Duan, Ruxu; Zhang, Changquan; Sun, Samuel Saiming; Liu, Qiaoquan

2017-05-31

Lysine is the first limiting essential amino acid in rice. We previously constructed a series of transgenic rice lines to enhance lysine biosynthesis (35S), down-regulate its catabolism (Ri), or simultaneously achieve both metabolic effects (35R). In this study, nine transgenic lines, three from each group, were selected for both field and animal feeding trials. The results showed that the transgene(s) caused no obvious effects on field performance and main agronomic traits. Mature seeds of transgenic line 35R-17 contained 48-60-fold more free lysine than in wild type and had slightly lower apparent amylose content and softer gel consistency. Moreover, a 35-day feeding experiment showed that the body weight gain, food efficiency, and protein efficiency ratio of rats fed the 35R-17 transgenic rice diet were improved when compared with those fed wild-type rice diet. These data will be useful for further evaluation and potential commercialization of 35R high-lysine transgenic rice.

Catabolism of 6-ketoprostaglandin F1alpha by the rat kidney cortex.

Science.gov (United States)

Pace-Asciak, C R; Domazet, Z; Carrara, M

1977-05-25

Homogenates of the rat kidney cortex converted 5,8,9,11,12,14,15-hepta-tritiated 6-ketoprostaglandin F 1alpha into one major product identified by gas chromatography-mass spectrometry of the methoxime-methyl ester trimethylsilyl ether derivative as 6,15-diketo-9,11-dihydroxyprost-13-enoic acid. The sequence of derivatisation i.e. methoximation prior to methylation, was crucial as methylation of 15-keto catabolites of the E, F and 6-keto-F series affords degradation products. The corresponding 15-keto-13,14-dihydro catabolite was formed in much smaller quantities. Time course studies indicated that 6-keto-prostaglandin F1alpha was catabolised at a slower rate (about 2-5 fold) than prostaglandin F1alpha. The catabolic activity was blocked by NADH.

Stabilization of neurotensin analogues: effect on peptide catabolism, biodistribution and tumor binding

Energy Technology Data Exchange (ETDEWEB)

Bruehlmeier, Matthias E-mail: peter.blaeuenstein@psi.ch; Garayoa, Elisa Garcia; Blanc, Alain; Holzer, Barbara; Gergely, Suzanne; Tourwe, Dirk; Schubiger, Pius August; Blaeuenstein, Peter

2002-04-01

Neurotensin (NT) receptors in pancreatic and other neuroendocrine tumors are promising targets for imaging and therapeutic purposes. Here, we report on the effect of distinct changes in the peptide chain on catabolism in vitro for five radiolabeled [{sup 99m}Tc] neurotensin analogues having high affinity for neurotensin receptors. Substitution of NT(1-7) by (N{alpha}His)Ac--the Tc-binding moiety--combined with a reduced bond 8-9 (CH{sub 2}NH), N-methylation of peptide bonds or replacement of Ile(12) by tertiary leucin (Tle) led to peptide stabilization of various degrees. Biodistribution studies in nude mice bearing HT29 xenografts showed higher tumor uptake with more stable peptides, yielding high tumor to blood ratios of up to 70.

Isolation and lipid degradation profile of Raoultella planticola strain 232-2 capable of efficiently catabolizing edible oils under acidic conditions.

Science.gov (United States)

Sugimori, Daisuke; Watanabe, Mika; Utsue, Tomohiro

2013-01-01

The lipids (fats and oils) degradation capabilities of soil microorganisms were investigated for possible application in treatment of lipids-contaminated wastewater. We isolated a strain of the bacterium Raoultella planticola strain 232-2 that is capable of efficiently catabolizing lipids under acidic conditions such as in grease traps in restaurants and food processing plants. The strain 232-2 efficiently catabolized a mixture (mixed lipids) of commercial vegetable oil, lard, and beef tallow (1:1:1, w/w/w) at 20-35 °C, pH 3-9, and 1,000-5,000 ppm lipid content. Highly effective degradation rate was observed at 35 °C and pH 4.0, and the 24-h degradation rate was 62.5 ± 10.5 % for 3,000 ppm mixed lipids. The 24-h degradation rate for 3,000 ppm commercial vegetable oil, lard, beef tallow, mixed lipids, and oleic acid was 71.8 %, 58.7 %, 56.1 %, 55.3 ± 8.5 %, and 91.9 % at pH 4 and 30 °C, respectively. R. planticola NBRC14939 (type strain) was also able to efficiently catabolize the lipids after repeated subculturing. The composition of the culture medium strongly influenced the degradation efficiency, with yeast extract supporting more complete dissimilation than BactoPeptone or beef extract. The acid tolerance of strain 232-2 is proposed to result from neutralization of the culture medium by urease-mediated decomposition of urea to NH(3). The rate of lipids degradation increased with the rates of neutralization and cell growth. Efficient lipids degradation using strain 232-2 has been achieved in the batch treatment of a restaurant wastewater.

Catabolic fate of Streptomyces viridosporus T7A-Produced, acid precipitable polymeric lignin upon incubation with ligninolytic Streptomyces species and Phanerochaete chrysosporium

International Nuclear Information System (INIS)

Pometto, A.L. III; Crawford, D.L.

1986-01-01

Degradation of ground and hot-water-extracted corn stover (Zea mays) lignocellulose by Streptomyces viridosporus T7A generates a water-soluble lignin degradation intermediate termed acid-precipitable polymeric lignin (APPL). The further catabolism of T7A-APPL by S. viridosporus T7A, S. badius 252, and S. setonii75Vi2 was followed for 3 weeks. APPL catabolism by Phanerochaete chrysosporium was followed in stationary cultures in a low-nitrogen medium containing 1% (wt/vol) glucose and 0.05% (wt/vol) T7A-APPL. Metabolism of the APPL was followed by turbidometric assay (600 nm) and by direct measurement of APPL recoverable from the medium. Accumulation and disappearance of soluble low-molecular-weight products of APPL catabolism were followed by gas-liquid chromatography and by high-pressure liquid chromatography, utilizing a diode array detector. Mineralization of a [ 14 C-lignin]APPL was also followed. The percent 14 C recovered as 14 CO 2 , 14 C-APPL, 14 C-labeled water-soluble products, and cell mass-associated radioactivity, were determined for each microorganism after 1 and 3 weeks of incubation in bubbler tube cultures at 37 0 C. P. chrysosporium evolved the most 14 CO 2 , and S. viridosporus gave the greatest decrease in recoverable 14 C-APPL. The results show that S. badius was not able to significantly degrade the APPL, while the other microorganisms demonstrated various APPL-degrading abilities

Brain protein synthesis in normal and demented patients. A study by P.E.T. with 11C-L methionine

International Nuclear Information System (INIS)

Bustany, P.; Soussaline, F.; Comar, D.; Henry, J.F.

1982-09-01

A compartmental model representing protein synthesis in the brain was validated experimentally in 9 baboons. After sequential injections of 11 C, 3 H and 14 C methionines on the same animal, followed by P.E.T. recording of the γ activity in a chosen brain section with time, the distribution of methionine injected into the different compartments of the model after a bolus was measured by crushing and precipitation with T.C.A. The agreement between direct in vitro findings and computed results is excellent. This method of studying brain protein synthesis in vivo was applied to 28 Alzheimer dementia cases and 20 normal subjects of the same age. The correlation between the results of clinical and psychometric tests and the brain protein synthesis activity confirms an anomaly in this biochemical synthesis process during the illness. A 65% fall in activity may be found in the frontal lobes of certain patients

Two gene clusters co-ordinate for a functional N-acetylglucosamine catabolic pathway in Vibrio cholerae.

Science.gov (United States)

Ghosh, Swagata; Rao, K Hanumantha; Sengupta, Manjistha; Bhattacharya, Sujit K; Datta, Asis

2011-06-01

Pathogenic microorganisms like Vibrio cholerae are capable of adapting to diverse living conditions, especially when they transit from their environmental reservoirs to human host. V. cholerae attaches to N-acetylglucosamine (GlcNAc) residues in glycoproteins and lipids present in the intestinal epithelium and chitinous surface of zoo-phytoplanktons in the aquatic environment for its survival and colonization. GlcNAc utilization thus appears to be important for the pathogen to reach sufficient titres in the intestine for producing clinical symptoms of cholera. We report here the involvement of a second cluster of genes working in combination with the classical genes of GlcNAc catabolism, suggesting the occurrence of a novel variant of the process of biochemical conversion of GlcNAc to Fructose-6-phosphate as has been described in other organisms. Colonization was severely attenuated in mutants that were incapable of utilizing GlcNAc. It was also shown that N-acetylglucosamine specific repressor (NagC) performs a dual role - while the classical GlcNAc catabolic genes are under its negative control, the genes belonging to the second cluster are positively regulated by it. Further application of tandem affinity purification to NagC revealed its interaction with a novel partner. Our results provide a genetic program that probably enables V. cholerae to successfully utilize amino - sugars and also highlights a new mode of transcriptional regulation, not described in this organism. © 2011 Blackwell Publishing Ltd.

Reprogramming One-Carbon Metabolic Pathways To Decouple l-Serine Catabolism from Cell Growth in Corynebacterium glutamicum.

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Zhang, Yun; Shang, Xiuling; Lai, Shujuan; Zhang, Yu; Hu, Qitiao; Chai, Xin; Wang, Bo; Liu, Shuwen; Wen, Tingyi

2018-02-16

l-Serine, the principal one-carbon source for DNA biosynthesis, is difficult for microorganisms to accumulate due to the coupling of l-serine catabolism and microbial growth. Here, we reprogrammed the one-carbon unit metabolic pathways in Corynebacterium glutamicum to decouple l-serine catabolism from cell growth. In silico model-based simulation showed a negative influence on glyA-encoding serine hydroxymethyltransferase flux with l-serine productivity. Attenuation of glyA transcription resulted in increased l-serine accumulation, and a decrease in purine pools, poor growth and longer cell shapes. The gcvTHP-encoded glycine cleavage (Gcv) system from Escherichia coli was introduced into C. glutamicum, allowing glycine-derived 13 CH 2 to be assimilated into intracellular purine synthesis, which resulted in an increased amount of one-carbon units. Gcv introduction not only restored cell viability and morphology but also increased l-serine accumulation. Moreover, comparative proteomic analysis indicated that abundance changes of the enzymes involved in one-carbon unit cycles might be responsible for maintaining one-carbon unit homeostasis. Reprogramming of the one-carbon metabolic pathways allowed cells to reach a comparable growth rate to accumulate 13.21 g/L l-serine by fed-batch fermentation in minimal medium. This novel strategy provides new insights into the regulation of cellular properties and essential metabolite accumulation by introducing an extrinsic pathway.

Effect of diet protein quality on growth and protein synthesis in rats

International Nuclear Information System (INIS)

Chinchalkar, D.V.; Mehta, S.L.

1978-01-01

The effect of diet protein quality on albino rats was studied by feeding normal and opaque-2 maize. The weight gain in rats was 60 percent higher on opaque-2 maize as compared to those fed on normal maize. Rats converted 1.0 g of dietary opaque-2 maize to 0.226 g weight gain as compared to 0.131 g for normal maize. The protein content per liver was higher with opaque-2 maize diet suggesting a higher net protein synthesis in opaque-2 maize fed rat livers. In vitro 14 C-phenylalanine incorporation showed that polysomes from opaque-2 maize fed rat livers were more efficient in protein synthesis than those from normal maize fed rat livers. Addition of poly-U resulted in more enhanced amino acid incorporation with polysomes from normal maize fed rats as compared to other group indicating greater limitation of mRNA in polysomes from normal maize fed rats. The total yield of liver polysomes from opaque-2 maize fed rats was substantially higher. (author)

Effect of transcutaneous electrical muscle stimulation on postoperative muscle mass and protein synthesis

DEFF Research Database (Denmark)

Vinge, O; Edvardsen, L; Jensen, F

1996-01-01

In an experimental study, 13 patients undergoing major elective abdominal surgery were given postoperative transcutaneous electrical muscle stimulation (TEMS) to the quadriceps femoris muscle on one leg; the opposite leg served as control. Changes in cross-sectional area (CSA) and muscle protein ...... protein synthesis and muscle mass after abdominal surgery and should be evaluated in other catabolic states with muscle wasting.......In an experimental study, 13 patients undergoing major elective abdominal surgery were given postoperative transcutaneous electrical muscle stimulation (TEMS) to the quadriceps femoris muscle on one leg; the opposite leg served as control. Changes in cross-sectional area (CSA) and muscle protein...... synthesis were assessed by computed tomography and ribosome analysis of percutaneous muscle biopsies before surgery and on the sixth postoperative day. The percentage of polyribosomes in the ribosome suspension decreased significantly (P

Potential Role of Vegetarianism on Nutritional and Cardiovascular Status in Taiwanese Dialysis Patients: A Case-Control Study.

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Shih-Hsiang Ou

Full Text Available Cardiovascular disease remains the most common cause of death for patients on chronic dialysis. End stage renal disease patients undergoing dialysis imposed to reduce phosphorus intake, which likely contributes to development of vegetarian diet behaviors. Vegetarian diets are often lower in protein content, in contradiction to the recommendation that a high protein diet is followed by patients undergoing dialysis. The purpose of the study was to investigate the effects of a vegetarian diet on the nutritional and cardiovascular status of dialysis patients.A study of 21 vegetarian dialysis patients and 42 age- and sex-matched non-vegetarian dialysis patients selected as controls was conducted in the Kaohsiung Veterans General Hospital. Brachial-ankle pulse wave velocity and biochemistry data including total homocysteine levels, serum lipid profiles, high-sensitivity C-reactive protein, vitamin D levels, albumin, and normalized protein catabolic rate were measured.Compared with the non-vegetarian control group, vegetarian subjects had lower body weight, body mass index, serum phosphate, blood urea nitrogen, serum creatinine, vitamin D, uric acid, albumin, and normalized protein catabolic rate (p < 0.05. The vegetarian group showed higher brachial-ankle pulse wave velocity than the non-vegetarian group (1926.95 ± 456.45 and 1684.82 ± 309.55 cm/sec, respectively, p < 0.05. After adjustment for age, albumin, pre-dialysis systolic blood pressure, and duration of dialysis, vegetarian diet remained an independent risk factor for brachial-ankle pulse wave velocity.The present study revealed that patients on dialysis who follow vegetarian diets may experience subclinical protein malnutrition and vitamin D deficiency that could offset the beneficial cardiovascular effects of vegetarianism.

An individual urinary proteome analysis in normal human beings to define the minimal sample number to represent the normal urinary proteome

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Liu Xuejiao

2012-11-01

Full Text Available Abstract Background The urinary proteome has been widely used for biomarker discovery. A urinary proteome database from normal humans can provide a background for discovery proteomics and candidate proteins/peptides for targeted proteomics. Therefore, it is necessary to define the minimum number of individuals required for sampling to represent the normal urinary proteome. Methods In this study, inter-individual and inter-gender variations of urinary proteome were taken into consideration to achieve a representative database. An individual analysis was performed on overnight urine samples from 20 normal volunteers (10 males and 10 females by 1DLC/MS/MS. To obtain a representative result of each sample, a replicate 1DLCMS/MS analysis was performed. The minimal sample number was estimated by statistical analysis. Results For qualitative analysis, less than 5% of new proteins/peptides were identified in a male/female normal group by adding a new sample when the sample number exceeded nine. In addition, in a normal group, the percentage of newly identified proteins/peptides was less than 5% upon adding a new sample when the sample number reached 10. Furthermore, a statistical analysis indicated that urinary proteomes from normal males and females showed different patterns. For quantitative analysis, the variation of protein abundance was defined by spectrum count and western blotting methods. And then the minimal sample number for quantitative proteomic analysis was identified. Conclusions For qualitative analysis, when considering the inter-individual and inter-gender variations, the minimum sample number is 10 and requires a balanced number of males and females in order to obtain a representative normal human urinary proteome. For quantitative analysis, the minimal sample number is much greater than that for qualitative analysis and depends on the experimental methods used for quantification.

A New Catabolic Plasmid in Xanthobacter and Starkeya spp. from a 1,2-Dichloroethane-Contaminated Site

Science.gov (United States)

Munro, Jacob E.; Liew, Elissa F.; Ly, Mai-Anh

2016-01-01

ABSTRACT 1,2-Dichloroethane (DCA) is a problematic xenobiotic groundwater pollutant. Bacteria are capable of biodegrading DCA, but the evolution of such bacteria is not well understood. In particular, the mechanisms by which bacteria acquire the key dehalogenase genes dhlA and dhlB have not been well defined. In this study, the genomic context of dhlA and dhlB was determined in three aerobic DCA-degrading bacteria (Starkeya novella strain EL1, Xanthobacter autotrophicus strain EL4, and Xanthobacter flavus strain EL8) isolated from a groundwater treatment plant (GTP). A haloalkane dehalogenase gene (dhlA) identical to the canonical dhlA gene from Xanthobacter sp. strain GJ10 was present in all three isolates, and, in each case, the dhlA gene was carried on a variant of a 37-kb circular plasmid, which was named pDCA. Sequence analysis of the repA replication initiator gene indicated that pDCA was a member of the pTAR plasmid family, related to catabolic plasmids from the Alphaproteobacteria, which enable growth on aromatics, dimethylformamide, and tartrate. Genes for plasmid replication, mobilization, and stabilization were identified, along with two insertion sequences (ISXa1 and ISPme1) which were likely to have mobilized dhlA and dhlB and played a role in the evolution of aerobic DCA-degrading bacteria. Two haloacid dehalogenase genes (dhlB1 and dhlB2) were detected in the GTP isolates; dhlB1 was most likely chromosomal and was similar to the canonical dhlB gene from strain GJ10, while dhlB2 was carried on pDCA and was not closely related to dhlB1. Heterologous expression of the DhlB2 protein confirmed that this plasmid-borne dehalogenase was capable of chloroacetate dechlorination. IMPORTANCE Earlier studies on the DCA-degrading Xanthobacter sp. strain GJ10 indicated that the key dehalogenases dhlA and dhlB were carried on a 225-kb linear plasmid and on the chromosome, respectively. The present study has found a dramatically different gene organization in more

Determination of Clara cell protein urinary elimination as a marker of tubular dysfunction.

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Martín-Granado, Ascensión; Vázquez-Moncholí, Carmen; Luis-Yanes, María Isabel; López-Méndez, Marisela; García-Nieto, Víctor

2009-04-01

Clara cell 16-kDa protein (CC16) is a protein expressed primarily by the bronchial cells. It is rapidly eliminated by glomerular filtration, reabsorbed almost entirely, and catabolized in proximal tubule cells. To date, normal values for urinary CC16 in healthy children have not been determined. We have studied 63 pediatric patients (mean age 8.17 +/- 3.91 years) and 31 healthy children (control group; mean age 8.83 +/- 3.65 years). In the control group, the CC16/creatinine ratio was 1.22 +/- 1.52 microg/g. In 16 out of 31 control children, the value of the ratio was zero. Fourteen patients (22.2%) showed a high CC16/creatinine ratio; in contrast, among these same patients, the ratio N-acetyl-beta-D: -glucosaminidase (NAG)/creatinine was elevated in seven cases (11.1%) and the ratio beta2-microglobulin/creatinine was elevated in seven cases (11.1%). The three parameters were in agreement in 51 patients (80.9%). Among the patients, the CC16/creatinine ratio was correlated with both the beta2-microglobulin/creatinina ratio (r = 0.76, P < 0.001) and the NAG/creatinine ratio (r = 0.6, P < 0.001). Our findings indicate that CC16 is a good marker of proximal tubular function in childhood. The highest observed values were in children with proximal tubulopathies, in children with chronic renal failure, and in those treated with cyclosporine.

Cytokine Release and Focal Adhesion Proteins in Normal Thyroid Cells Cultured on the Random Positioning Machine

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Elisabeth Warnke

2017-08-01

Full Text Available Background/Aims: Spaceflight impacts on the function of the thyroid gland in vivo. In vitro normal and malignant thyrocytes assemble in part to multicellular spheroids (MCS after exposure to the random positioning machine (RPM, while a number of cells remain adherent (AD. We aim to elucidate possible differences between AD and MCS cells compared to 1g-controls of normal human thyroid cells. Methods: Cells of the human follicular epithelial thyroid cell line Nthy-ori 3-1 were incubated for up to 72 h on the RPM. Afterwards, they were investigated by phase-contrast microscopy, quantitative real-time PCR and by determination of cytokines released in their supernatants. Results: A significant up-regulation of IL6, IL8 and CCL2 gene expression was found after a 4h RPM-exposure, when the whole population was still growing adherently. MCS and AD cells were detected after 24 h on the RPM. At this time, a significantly reduced gene expression in MCS compared to 1g-controls was visible for IL6, IL8, FN1, ITGB1, LAMA1, CCL2, and TLN1. After a 72 h RPM-exposure, IL-6, IL-8, and TIMP-1 secretion rates were increased significantly. Conclusion: Normal thyrocytes form MCS within 24 h. Cytokines seem to be involved in the initiation of MCS formation via focal adhesion proteins.

Myb proteins: angels and demons in normal and transformed cells.

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Zhou, Ye; Ness, Scott A

2011-01-01

A key regulator of proliferation, differentiation and cell fate, the c-Myb transcription factor regulates the expression of hundreds of genes and is in turn regulated by numerous pathways and protein interactions. However, the most unique feature of c-Myb is that it can be converted into an oncogenic transforming protein through a few mutations that completely change its activity and specificity. The c-Myb protein is a myriad of interactions and activities rolled up in a protein that controls proliferation and differentiation in many different cell types. Here we discuss the background and recent progress that have led to a better understanding of this complex protein, and outline the questions that have yet to be answered.

Protein supplementation with sports protein bars in renal patients.

Science.gov (United States)

Meade, Anthony

2007-05-01

bars as the preferred supplement. The major reasons for not continuing were taste and chewability, especially in older patients with dentures. Serum potassium and phosphate levels were not increased with supplementation. Measured serum albumin and protein catabolic rate were considered unreliable indicators because not all patients were medically stable. Sports protein bars are an acceptable protein and energy supplement for patients on hemodialysis. Sports protein bars are well accepted by patients except when dentures limit chewability. Sports protein bars have advantages over fluid-based supplements in patients with fluid restrictions.

A comprehensive two-dimensional gel protein database of noncultured unfractionated normal human epidermal keratinocytes: towards an integrated approach to the study of cell proliferation, differentiation and skin diseases

DEFF Research Database (Denmark)

Celis, J E; Madsen, Peder; Rasmussen, H H

1991-01-01

A two-dimensional (2-D) gel database of cellular proteins from noncultured, unfractionated normal human epidermal keratinocytes has been established. A total of 2651 [35S]methionine-labeled cellular proteins (1868 isoelectric focusing, 783 nonequilibrium pH gradient electrophoresis) were resolved...

[Morphology of basement membrane and associated matrix proteins in normal and pathological tissues].

Science.gov (United States)

Nerlich, A

1995-01-01

Basement membranes (BM) are specialized structures of the extracellular matrix. Their composition is of particular importance for the maintenance of normal morphological and functional properties of a multitude of organs and tissue systems and it is thus required for regular homeostasis of body function. Generally, they possess three main functions, i.e. participation in the maintenance of tissue structure, control of fluid and substrate exchange, and regulation of cell growth and differentiation. BMs are made up by various components which are in part specifically localized within the BM zone, or which represent ubiquitous matrix constituents with specific quantitative and/or qualitative differences in their localization. On the basis of a thorough immunohistochemical analysis of normal and diseased tissues, we provide here a concept of "functional morphology/pathomorphology" of the different BM components analyzed: 1.) The ubiquitous BM-constituent collagen IV primarily stabilizes the BM-zone and thus represents the "backbone" of the BM providing mechanical strength. Its loss leads to cystic tissue transformation as it is evidenced from the analysis of polycystic nephropathies. Thus, in other cystic tissue transformations a similar formal pathogenesis may be present. 2.) The specific localization of collagen VII as the main structural component of anchoring fibrils underlines the mechanical anchoring function of this collagenous protein. Defects in this protein lead to hereditary epidermolysis. The rapid re-occurrence of epidermal collagen VII during normal human wound healing indicates a quick reconstitution of the mechanical tensile strength of healing wounds. 3.) The BM-specific heparan sulfate proteoglycan (HSPG, Perlecan) with its highly negative anionic charge can be assumed to exert filter control. This assumption is corroborated by the localizatory findings of a preferential deposition of HSPG in endothelial and particularly in glomerular BM. Similarly

High insulin-like growth factor-binding protein-1 (IGFBP-1) is associated with low relative muscle mass in older women

DEFF Research Database (Denmark)

Stilling, Frej; Wallenius, Sara; Michaëlsson, Karl

2017-01-01

. In the present study we investigate the association between serum IGFBP-1 and muscle mass. Design Cross-sectional analysis of 4908 women, between 55 and 85 years old, participating in the Swedish Mammography Cohort-Clinical. Methods We defined low relative muscle mass (LRMM) as an appendicular lean mass divided...... relative muscle mass. High IGFBP-1 may be a marker of a catabolic state.......Objective Skeletal muscles serve several important roles in maintaining good health. Insulin-like growth factor-1 (IGF-1) is a promoter of protein synthesis in skeletal muscle. Its binding protein, Insulin-like growth factor-binding protein-1 (IGFBP-1) can be one determinant of IGF-1 activity...

Regulatory role of XynR (YagI) in catabolism of xylonate in Escherichia coli K-12.

Science.gov (United States)

Shimada, Tomohiro; Momiyama, Eri; Yamanaka, Yuki; Watanabe, Hiroki; Yamamoto, Kaneyoshi; Ishihama, Akira

2017-12-01

The genome of Escherichia coli K-12 contains ten cryptic phages, altogether constituting about 3.6% of the genome in sequence. Among more than 200 predicted genes in these cryptic phages, 14 putative transcription factor (TF) genes exist, but their regulatory functions remain unidentified. As an initial attempt to make a breakthrough for understanding the regulatory roles of cryptic phage-encoded TFs, we tried to identify the regulatory function of CP4-6 cryptic prophage-encoded YagI with unknown function. After SELEX screening, YagI was found to bind mainly at a single site within the spacer of bidirectional transcription units, yagA (encoding another uncharacterized TF) and yagEF (encoding 2-keto-3-deoxy gluconate aldolase, and dehydratase, respectively) within this prophage region. YagEF enzymes are involved in the catabolism of xylose downstream from xylonate. We then designated YagI as XynR (regulator of xylonate catabolism), one of the rare single-target TFs. In agreement with this predicted regulatory function, the activity of XynR was suggested to be controlled by xylonate. Even though low-affinity binding sites of XynR were identified in the E. coli K-12 genome, they all were inside open reading frames, implying that the regulation network of XynR is still fixed within the CR4-6 prophage without significant influence over the host E. coli K-12. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Synthesis and evaluation of radioactive and fluorescent residualizing labels for identifying sites of plasma protein catabolism

International Nuclear Information System (INIS)

Maxwell, J.L.; Baynes, J.W.; Thorpe, S.R.

1986-01-01

Inulin and lactose were each coupled to tyramine by reductive amination with NaBH 3 CN and the tyramine then labeled with 125 I. Dilactitol- 125 I-tyramine (DLT) and inulin- 125 I-tyramine (InTn) were coupled by reductive amination and cyanuric chloride, respectively, to asialofetuin (ASF), fetuin and rat serum albumin (RSA). Attachment of either label had no effect on the circulating half-lives of the proteins. Radioactivity from labeled ASF was recovered in rat liver (> 90%) by 1 h post-injection and remained in liver with half-lives of 2 and 6 days, respectively, for the DLT and InTn labels. Whole body recoveries of radioactivity from DLT- and InTn labels. Whole body recoveries of radioactivity from DLT- and InTn-labeled RSA were 5 and 6.5 days, respectively, again indicating that the larger glycoconjugate label residualized more efficiently in cells following protein degradation. (Lactitol) 2 -N-CH 2 -CH 2 -NH-fluroescein (DLF) was also coupled to ASF by reductive amination and recovered quantitatively in liver at 1 h post-injection. Native ASF was an effective competitor for clearance of DLF-ASF from the circulation. Fluorescent degradation products were retained in liver with a half-life of 1.2 days. Residualizing fluorescent labels should be useful for identification and sorting of cells active in the degradation of plasma proteins

Ramadan Fasting Decreases Body Fat but Not Protein Mass.

Science.gov (United States)

Fahrial Syam, Ari; Suryani Sobur, Cecep; Abdullah, Murdani; Makmun, Dadang

2016-01-01

Many studies have shown various results regarding the effects of Ramadan fasting on weight and body composition in healthy individuals. This study aimed to evaluate the effect of Ramadan fasting on body composition in healthy Indonesian medical staff. In this study, we examined the influence of Ramadan fasting on body composition in healthy medical staff. The longitudinal study was performed during and after Ramadan fasting in 2013 (August to October). Fourty-three medical staff members (physicians, nurses and nutritionists) at the Internal Medicine Ward of the Dr. Cipto Mangunkusumo General Hospital were measured to compare their calorie intake, weight, body mass index, waist-to-hip ratio (WHR), and body composition, including body fat, protein, minerals and water, on the first and 28(th) days of Ramadan and also 4-5 weeks after Ramadan fasting. Measurements were obtained for all 43 subjects on the 28(th) day of Ramadan, but they were obtained for only 25 subjects 4 - 5 weeks after Ramadan. By the 28(th) day of Ramadan, it was found that the body weight, BMI, body fat, water and mineral measures had decreased significantly (-0.874 ± 0.859 kg, P Ramadan, body weight and composition had returned to the same levels as on the first day of Ramadan. Ramadan fasting resulted in weight loss even it was only a temporary effect, as the weight was quickly regained within one month after fasting. The catabolism catabolic state, which is related to protein loss, was not triggered during Ramadan fasting. Further research is needed to evaluate the effects of weight loss during Ramadan fasting in healthy individuals.

Catabolic and regulatory systems in Shewanella oneidensis MR-1 involved in electricity generation in microbial fuel cells

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Atsushi eKouzuma

2015-06-01

Full Text Available Shewanella oneidensis MR-1 is a facultative anaerobe that respires using a variety of inorganic and organic compounds. MR-1 is also capable of utilizing extracellular solid materials, including anodes in microbial fuel cells (MFCs, as electron acceptors, thereby enabling electricity generation. As MFCs have the potential to generate electricity from biomass waste and wastewater, MR-1 has been extensively studied to identify the molecular systems that are involved in electricity generation in MFCs. These studies have demonstrated the importance of extracellular electron-transfer pathways that electrically connect the quinone pool in the cytoplasmic membrane to extracellular electron acceptors. Electricity generation is also dependent on intracellular catabolic pathways that oxidize electron donors, such as lactate, and regulatory systems that control the expression of genes encoding the components of catabolic and electron-transfer pathways. In addition, recent findings suggest that cell-surface polymers, e.g., exopolysaccharides, and secreted chemicals, which function as electron shuttles, are also involved in electricity generation. Despite these advances in our knowledge on the extracellular electron-transfer processes in MR-1, further efforts are necessary to fully understand the underlying intra- and extra-cellular molecular systems for electricity generation in MFCs. We suggest that investigating how MR-1 coordinates these systems to efficiently transfer electrons to electrodes and conserve electrochemical energy for cell proliferation is important for establishing the biological bases for MFCs.

Bovine lactoferricin, an antimicrobial peptide, is anti-inflammatory and anti-catabolic in human articular cartilage and synovium

Science.gov (United States)

Yan, Dongyao; Chen, Di; Shen, Jie; Xiao, Guozhi; van Wijnen, Andre J; Im, Hee-Jeong

2012-01-01

Bovine lactoferricin (LfcinB) is a multi-functional peptide derived from proteolytic cleavage of bovine lactoferrin. LfcinB was found to antagonize the biological effects mediated by angiogenic growth factors such as vascular endothelial growth factor (VEGF) and fibroblast growth factor 2 (FGF-2) in endothelial cells. However, the effect of LfcinB on human articular cartilage remained unknown. Here, our findings demonstrate that LfcinB restored the proteoglycan loss promoted by catabolic factors (interleukin-1 β) IL-1β and FGF-2 in vitro and ex vivo. Mechanistically, LfcinB attenuated the effects of IL-1β and FGF-2 on the expression of cartilage-degrading enzymes (MMP-1, MMP-3, and MMP-13), destructive cytokines (IL-1β and IL-6), and inflammatory mediators (iNOS and TLR2). LfcinB induced protective cytokine expression (IL-4 and IL-10), and downregulated aggrecanase basal expression. LfcinB specifically activated ERK MAPK and Akt signaling pathways, which may account for its anti-inflammatory activity. We also revealed that LfcinB exerted similar protective effects on human synovial fibroblasts challenged by IL-1β, with minimal cytotoxicity. Collectively, our results suggest that LfcinB possesses potent anti-catabolic and anti-inflammatory bioactivities in human articular tissues, and may be utilized for the prevention and/or treatment of OA in the future. PMID:22740381

AMP-activated protein kinase in contraction regulation of skeletal muscle metabolism: necessary and/or sufficient?

DEFF Research Database (Denmark)

Jensen, Thomas Elbenhardt; Wojtaszewski, Jørgen; Richter, Erik

2009-01-01

In skeletal muscle, the contraction-activated heterotrimeric 5'-AMP-activated protein kinase (AMPK) protein is proposed to regulate the balance between anabolic and catabolic processes by increasing substrate uptake and turnover in addition to regulating the transcription of proteins involved...... in mitochondrial biogenesis and other aspects of promoting an oxidative muscle phenotype. Here, the current knowledge on the expression of AMPK subunits in human quadriceps muscle and evidence from rodent studies suggesting distinct AMPK subunit expression pattern in different muscle types is reviewed. Then......, the intensity and time dependence of AMPK activation in human quadriceps and rodent muscle are evaluated. Subsequently, a major part of this review critically examines the evidence supporting a necessary and/or sufficient role of AMPK in a broad spectrum of skeletal muscle contraction-relevant processes...

Low serum levels of free and total insulin-like growth factor I (IGF-I) in patients with anorexia nervosa are not associated with increased IGF-binding protein-3 proteolysis

DEFF Research Database (Denmark)

Støving, R K; Flyvbjerg, A; Frystyk, J

1999-01-01

Patients with anorexia nervosa (AN) are GH resistant, with elevated GH levels and low serum levels of total insulin-like growth factor I (IGF-I). IGF-I action is modulated by IGF-binding proteins (IGFBPs), and a variety of catabolic states has been characterized by the presence of increased IGFBP-3...

The Hypocrea jecorina (syn. Trichoderma reesei) lxr1 gene encodes a D-mannitol dehydrogenase and is not involved in L-arabinose catabolism

NARCIS (Netherlands)

Metz, Benjamin; de Vries, Ronald P; Polak, Stefan; Seidl, Verena; Seiboth, Bernhard

2009-01-01

The Hypocrea jecorina LXR1 was described as the first fungal L-xylulose reductase responsible for NADPH dependent reduction of L-xylulose to xylitol in L-arabinose catabolism. Phylogenetic analysis now reveals that LXR1 forms a clade with fungal D-mannitol 2-dehydrogenases. Lxr1 and the orthologous

Microbial biotin protein ligases aid in understanding holocarboxylase synthetase deficiency.

Science.gov (United States)

Pendini, Nicole R; Bailey, Lisa M; Booker, Grant W; Wilce, Matthew C; Wallace, John C; Polyak, Steven W

2008-01-01

The attachment of biotin onto the biotin-dependent enzymes is catalysed by biotin protein ligase (BPL), also known as holocarboxylase synthase HCS in mammals. Mammals contain five biotin-enzymes that participate in a number of important metabolic pathways such as fatty acid biogenesis, gluconeogenesis and amino acid catabolism. All mammalian biotin-enzymes are post-translationally biotinylated, and therefore activated, through the action of a single HCS. Substrate recognition by BPLs occurs through conserved structural cues that govern the specificity of biotinylation. Defects in biotin metabolism, including HCS, give rise to multiple carboxylase deficiency (MCD). Here we review the literature on this important enzyme. In particular, we focus on the new information that has been learned about BPL's from a number of recently published protein structures. Through molecular modelling studies insights into the structural basis of HCS deficiency in MCD are discussed.

Both near ultraviolet radiation and the oxidizing agent hydrogen peroxide induce a 32-kDa stress protein in normal human skin fibroblasts

International Nuclear Information System (INIS)

Keyse, S.M.; Tyrrell, R.M.

1987-01-01

We have analyzed the pattern of protein synthesis in solar near ultraviolet (334 nm, 365 nm) and near visible (405 nm) irradiated normal human skin fibroblasts. Two hours after irradiation we find that one major stress protein of approximately 32 kDa is induced in irradiated cells. This protein is not induced by ultraviolet radiation at wavelengths shorter than 334 nm and is not inducible by heat shock treatment of these cells. Although sodium arsenite, diamide, and menadione all induced a 32-kDa protein, they also induced the major heat shock proteins. In contrast, the oxidizing agent, hydrogen peroxide, induced the low molecular weight stress protein without causing induction of the major heat shock proteins. A comparison of the 32-kDa proteins induced by sodium arsenite, H 2 O 2 , and solar near ultraviolet radiation using chemical peptide mapping shows that they are closely related. These results imply that the pathways for induction of the heat shock response and the 32-kDa protein are not identical and suggest that, at least in the case of radiation and treatment with H 2 O 2 , the 32-kDa protein might be induced in response to cellular oxidative stress. This conclusion is supported by the observation that depletion of endogenous cellular glutathione prior to solar near ultraviolet irradiation lowers the fluence threshold for induction of the 32-kDa stress protein

Adipokines induce catabolism of newly synthesized matrix in cartilage and meniscus tissues.

Science.gov (United States)

Nishimuta, James F; Levenston, Marc E

Altered synovial levels of various adipokines (factors secreted by fat as well as other tissues) have been associated with osteoarthritis (OA) onset and progression. However, the metabolic effects of adipokines on joint tissues, in particular the fibrocartilaginous menisci, are not well understood. This study investigated effects of several adipokines on release of recently synthesized extracellular matrix in bovine cartilage and meniscus tissue explants. After labeling newly synthesized proteins and sulfated glycosaminoglycans (sGAGs) with 3 H-proline and 35 S-sulfate, respectively; bovine cartilage and meniscus tissue explants were cultured for 6 days in basal medium (control) or media supplemented with adipokines (1 µg/ml of leptin, visfatin, adiponectin, or resistin) or 20 ng/ml interleukin-1 (IL-1). Release of radiolabel and sGAG to the media during culture and the final explant water, DNA, sGAG, and retained radiolabel were measured. Matrix metalloproteinase (MMP-2) and MMP-3 activities were assessed using gelatin and casein zymography, respectively. Water and DNA contents were not significantly altered by any treatment. Visfatin, adiponectin, resistin, and IL-1 stimulated sGAG release from meniscus, whereas only IL-1 stimulated sGAG release from cartilage. Release of 3 H and 35 S was stimulated not only by resistin and IL-1 in meniscus but also by IL-1 in cartilage. Retained 3 H was unaltered by any treatment, while retained 35 S was reduced by visfatin, resistin, and IL-1 in meniscus and by only IL-1 in cartilage. Resistin and IL-1 elevated active MMP-2 and total MMP-3 in meniscus, whereas cartilage MMP-3 activity was elevated by only IL-1. Resistin stimulated rapid and extensive catabolism of meniscus tissue, similar to IL-1, whereas adipokines minimally affected cartilage. Release of newly synthesized matrix was similar to overall release in both tissues. These observations provide further indications that meniscal tissue is more sensitive to pro

Effects of anti-proteinuric therapy with angiotensin-converting-enzyme inhibition on renal protein catabolism in the adriamycin-induced nephrotic rat

NARCIS (Netherlands)

Haas, M; de Jong, PE; Moolenaar, F; Meijer, DKF; de Zeeuw, D

A direct consequence of glomerular protein leakage is an increased exposure of proximal tubular cells to proteins. The aim of the present study was to examine whether chronic proteinuria affects the tubular handling of proteins and whether anti-proteinuric therapy by angiotensin-converting-enzyme

Conformational variability of the stationary phase survival protein E from Xylella fastidiosa revealed by X-ray crystallography, small-angle X-ray scattering studies, and normal mode analysis.

Science.gov (United States)

Machado, Agnes Thiane Pereira; Fonseca, Emanuella Maria Barreto; Reis, Marcelo Augusto Dos; Saraiva, Antonio Marcos; Santos, Clelton Aparecido Dos; de Toledo, Marcelo Augusto Szymanski; Polikarpov, Igor; de Souza, Anete Pereira; Aparicio, Ricardo; Iulek, Jorge

2017-10-01

Xylella fastidiosa is a xylem-limited bacterium that infects a wide variety of plants. Stationary phase survival protein E is classified as a nucleotidase, which is expressed when bacterial cells are in the stationary growth phase and subjected to environmental stresses. Here, we report four refined X-ray structures of this protein from X. fastidiosa in four different crystal forms in the presence and/or absence of the substrate 3'-AMP. In all chains, the conserved loop verified in family members assumes a closed conformation in either condition. Therefore, the enzymatic mechanism for the target protein might be different of its homologs. Two crystal forms exhibit two monomers whereas the other two show four monomers in the asymmetric unit. While the biological unit has been characterized as a tetramer, differences of their sizes and symmetry are remarkable. Four conformers identified by Small-Angle X-ray Scattering (SAXS) in a ligand-free solution are related to the low frequency normal modes of the crystallographic structures associated with rigid body-like protomer arrangements responsible for the longitudinal and symmetric adjustments between tetramers. When the substrate is present in solution, only two conformers are selected. The most prominent conformer for each case is associated to a normal mode able to elongate the protein by moving apart two dimers. To our knowledge, this work was the first investigation based on the normal modes that analyzed the quaternary structure variability for an enzyme of the SurE family followed by crystallography and SAXS validation. The combined results raise new directions to study allosteric features of XfSurE protein. © 2017 Wiley Periodicals, Inc.

Sialic Acid Catabolism Confers a Competitive Advantage to Pathogenic Vibrio cholerae in the Mouse Intestine▿

Science.gov (United States)

Almagro-Moreno, Salvador; Boyd, E. Fidelma

2009-01-01

Sialic acids comprise a family of nine-carbon ketosugars that are ubiquitous on mammalian mucous membranes. However, sialic acids have a limited distribution among Bacteria and are confined mainly to pathogenic and commensal species. Vibrio pathogenicity island 2 (VPI-2), a 57-kb region found exclusively among pathogenic strains of Vibrio cholerae, contains a cluster of genes (nan-nag) putatively involved in the scavenging (nanH), transport (dctPQM), and catabolism (nanA, nanE, nanK, and nagA) of sialic acid. The capacity to utilize sialic acid as a carbon and energy source might confer an advantage to V. cholerae in the mucus-rich environment of the gut, where sialic acid availability is extensive. In this study, we show that V. cholerae can utilize sialic acid as a sole carbon source. We demonstrate that the genes involved in the utilization of sialic acid are located within the nan-nag region of VPI-2 by complementation of Escherichia coli mutants and gene knockouts in V. cholerae N16961. We show that nanH, dctP, nanA, and nanK are highly expressed in V. cholerae grown on sialic acid. By using the infant mouse model of infection, we show that V. cholerae ΔnanA strain SAM1776 is defective in early intestinal colonization stages. In addition, SAM1776 shows a decrease in the competitive index in colonization-competition assays comparing the mutant strain with both O1 El Tor and classical strains. Our data indicate an important relationship between the catabolism of sialic acid and bacterial pathogenesis, stressing the relevance of the utilization of the resources found in the host's environment. PMID:19564383

Sialic acid catabolism confers a competitive advantage to pathogenic vibrio cholerae in the mouse intestine.

Science.gov (United States)

Almagro-Moreno, Salvador; Boyd, E Fidelma

2009-09-01

Sialic acids comprise a family of nine-carbon ketosugars that are ubiquitous on mammalian mucous membranes. However, sialic acids have a limited distribution among Bacteria and are confined mainly to pathogenic and commensal species. Vibrio pathogenicity island 2 (VPI-2), a 57-kb region found exclusively among pathogenic strains of Vibrio cholerae, contains a cluster of genes (nan-nag) putatively involved in the scavenging (nanH), transport (dctPQM), and catabolism (nanA, nanE, nanK, and nagA) of sialic acid. The capacity to utilize sialic acid as a carbon and energy source might confer an advantage to V. cholerae in the mucus-rich environment of the gut, where sialic acid availability is extensive. In this study, we show that V. cholerae can utilize sialic acid as a sole carbon source. We demonstrate that the genes involved in the utilization of sialic acid are located within the nan-nag region of VPI-2 by complementation of Escherichia coli mutants and gene knockouts in V. cholerae N16961. We show that nanH, dctP, nanA, and nanK are highly expressed in V. cholerae grown on sialic acid. By using the infant mouse model of infection, we show that V. cholerae DeltananA strain SAM1776 is defective in early intestinal colonization stages. In addition, SAM1776 shows a decrease in the competitive index in colonization-competition assays comparing the mutant strain with both O1 El Tor and classical strains. Our data indicate an important relationship between the catabolism of sialic acid and bacterial pathogenesis, stressing the relevance of the utilization of the resources found in the host's environment.

Use of wheat and maize protein mutants in breeding for improved protein quantity and quality

International Nuclear Information System (INIS)

Denic, M.; Dumanovic, J.; Misevic, D.; Konstantinov, K.; Fidler, D.; Stojanovic, Z.

1984-01-01

Selected offspring progenies (50 mutant lines) originating from mutation experiments with hexaploid wheat (cv. Bezostaya 1) were analysed for induced heritable variation in protein content, lysine content, grain yield and protein and lysine yields. Ten of these mutant lines were crossed with 11 local varieties. The protein and lysine contents were measured in the progenies of these crossings. The data showed better correlations of grain yield with protein and lysine yields than the protein and lysine contents with their corresponding yields. F 1 seeds showed higher lysine and protein contents than local varieties. Data with maize showed that: (1) the total endosperm protein content of modified opaque-2 types increases with an increase in the degree of normalization; (2) the lysine content in dry matter and protein in normalized o 2 kernels usually decreases with the increasing degree of normalization; (3) the lysine content in protein of modified o 2 kernels, is, in general, satisfactory up to the normalization of about 50% of endosperm. A desirable modification of o 2 endosperm within line A632o 2 was selected and crossed with o 2 lines. Most of the tested hybrids had a good protein quality, but endosperm modification was not evident in all hybrids. The o 2 gene was incorporated into high protein backgrounds. Besides a high protein content and quality, some of the hybrids tested had a comparable or higher yield than the o 2 check. (author)

Biodistribution and catabolism of 18F-labeled N-ε-fructoselysine as a model of Amadori products

International Nuclear Information System (INIS)

Hultsch, Christina; Hellwig, Michael; Pawelke, Beate; Bergmann, Ralf; Rode, Katrin; Pietzsch, Jens; Krause, Rene; Henle, Thomas

2006-01-01

Amadori products are formed in the early stage of the so-called Maillard reaction between reducing sugars and amino acids or proteins. Such nonenzymatic glycosylation may occur during the heating or storage of foods, but also under physiological conditions. N-ε-fructoselysine is formed via this reaction between the ε-amino group of peptide-bound lysine and glucose. Despite the fact that, in certain heated foods, up to 50% of lysyl moieties may be modified to such lysine derivatives, up to now, very little is known about the metabolic fate of alimentary administered Amadori compounds. In the present study, N-succinimidyl-4-[ 18 F]fluorobenzoate was used to modify N-ε-fructoselysine at the α-amino group of the lysyl moiety. The in vitro stability of the resulting 4-[ 18 F]fluorobenzoylated derivative was tested in different tissue homogenates. Furthermore, the 4-[ 18 F]fluorobenzoylated N-ε-fructoselysine was used in positron emission tomography studies, as well as in studies concerning biodistribution and catabolism. The results show that the 4-[ 18 F]fluorobenzoylated N-ε-fructoselysine is phosphorylated in vitro, as well as in vivo. This phosphorylation is caused by fructosamine 3-kinases and occurs in vivo, particularly in the kidneys. Despite the action of these enzymes, it was shown that a large part of the intravenously applied radiolabeled N-ε-fructoselysine was excreted nearly unchanged in the urine. Therefore, it was concluded that the predominant part of peptide-bound lysine that was fructosylated during food processing is not available for nutrition

Biodistribution and catabolism of 18F-labeled N-epsilon-fructoselysine as a model of Amadori products.

Science.gov (United States)

Hultsch, Christina; Hellwig, Michael; Pawelke, Beate; Bergmann, Ralf; Rode, Katrin; Pietzsch, Jens; Krause, René; Henle, Thomas

2006-10-01

Amadori products are formed in the early stage of the so-called Maillard reaction between reducing sugars and amino acids or proteins. Such nonenzymatic glycosylation may occur during the heating or storage of foods, but also under physiological conditions. N-epsilon-fructoselysine is formed via this reaction between the epsilon-amino group of peptide-bound lysine and glucose. Despite the fact that, in certain heated foods, up to 50% of lysyl moieties may be modified to such lysine derivatives, up to now, very little is known about the metabolic fate of alimentary administered Amadori compounds. In the present study, N-succinimidyl-4-[18F]fluorobenzoate was used to modify N-epsilon-fructoselysine at the alpha-amino group of the lysyl moiety. The in vitro stability of the resulting 4-[18F]fluorobenzoylated derivative was tested in different tissue homogenates. Furthermore, the 4-[18F]fluorobenzoylated N-epsilon-fructoselysine was used in positron emission tomography studies, as well as in studies concerning biodistribution and catabolism. The results show that the 4-[18F]fluorobenzoylated N-epsilon-fructoselysine is phosphorylated in vitro, as well as in vivo. This phosphorylation is caused by fructosamine 3-kinases and occurs in vivo, particularly in the kidneys. Despite the action of these enzymes, it was shown that a large part of the intravenously applied radiolabeled N-epsilon-fructoselysine was excreted nearly unchanged in the urine. Therefore, it was concluded that the predominant part of peptide-bound lysine that was fructosylated during food processing is not available for nutrition.

ABF2, ABF3, and ABF4 Promote ABA-Mediated Chlorophyll Degradation and Leaf Senescence by Transcriptional Activation of Chlorophyll Catabolic Genes and Senescence-Associated Genes in Arabidopsis.

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Gao, Shan; Gao, Jiong; Zhu, Xiaoyu; Song, Yi; Li, Zhongpeng; Ren, Guodong; Zhou, Xin; Kuai, Benke

2016-09-06

Chlorophyll (Chl) degradation is an integral process of leaf senescence, and NYE1/SGR1 has been demonstrated as a key regulator of Chl catabolism in diverse plant species. In this study, using yeast one-hybrid screening, we identified three abscisic acid (ABA)-responsive element (ABRE)-binding transcription factors, ABF2 (AREB1), ABF3, and ABF4 (AREB2), as the putative binding proteins of the NYE1 promoter. Through the transactivation analysis, electrophoretic mobility shift assay, and chromatin immunoprecipitation, we demonstrated that ABF2, ABF3, and ABF4 directly bound to and activated the NYE1 promoter in vitro and in vivo. ABA is a positive regulator of leaf senescence, and exogenously applied ABA can accelerate Chl degradation. The triple mutant of the ABFs, abf2abf3abf4, as well as two ABA-insensitive mutants, abi1-1 and snrk2.2/2.3/2.6, exhibited stay-green phenotypes after ABA treatment, along with decreased induction of NYE1 and NYE2 expression. In contrast, overexpression of ABF4 accelerated Chl degradation upon ABA treatment. Interestingly, ABF2/3/4 could also activate the expression of two Chl catabolic enzyme genes, PAO and NYC1, by directly binding to their promoters. In addition, abf2abf3abf4 exhibited a functional stay-green phenotype, and senescence-associated genes (SAGs), such as SAG29 (SWEET15), might be directly regulated by the ABFs. Taken together, our results suggest that ABF2, ABF3, and ABF4 likely act as key regulators in mediating ABA-triggered Chl degradation and leaf senescence in general in Arabidopsis. Copyright © 2016 The Author. Published by Elsevier Inc. All rights reserved.

Repression of protein translation and mTOR signaling by proteasome inhibitor in colon cancer cells

International Nuclear Information System (INIS)

Wu, William Ka Kei; Volta, Viviana; Cho, Chi Hin; Wu, Ya Chun; Li, Hai Tao; Yu, Le; Li, Zhi Jie; Sung, Joseph Jao Yiu

2009-01-01

Protein homeostasis relies on a balance between protein synthesis and protein degradation. The ubiquitin-proteasome system is a major catabolic pathway for protein degradation. In this respect, proteasome inhibition has been used therapeutically for the treatment of cancer. Whether inhibition of protein degradation by proteasome inhibitor can repress protein translation via a negative feedback mechanism, however, is unknown. In this study, proteasome inhibitor MG-132 lowered the proliferation of colon cancer cells HT-29 and SW1116. In this connection, MG-132 reduced the phosphorylation of mammalian target of rapamycin (mTOR) at Ser2448 and Ser2481 and the phosphorylation of its downstream targets 4E-BP1 and p70/p85 S6 kinases. Further analysis revealed that MG-132 inhibited protein translation as evidenced by the reductions of 35 S-methionine incorporation and polysomes/80S ratio. Knockdown of raptor, a structural component of mTOR complex 1, mimicked the anti-proliferative effect of MG-132. To conclude, we demonstrate that the inhibition of protein degradation by proteasome inhibitor represses mTOR signaling and protein translation in colon cancer cells.

Molecular analysis of quality protein (QPM) and normal maize ...

African Journals Online (AJOL)

Jane

2011-10-24

Oct 24, 2011 ... genetic variation among QPM and normal maize varieties is important for an efficient selection and .... olymerase chain reaction (PCR) amplifications of RAPD and ISSR ..... Genetic characterization of Malawian cowpea.

Effect of high-protein or normal-protein diet on weight loss, body composition, hormone, and metabolic profile in southern Brazilian women with polycystic ovary syndrome: a randomized study.

Science.gov (United States)

Toscani, Mariana K; Mario, Fernanda M; Radavelli-Bagatini, Simone; Wiltgen, Denusa; Matos, Maria Cristina; Spritzer, Poli Maria

2011-11-01

The aim of the present study was to assess the effects of a high protein (HP) and a normal protein (NP) diet on patients with polycystic ovary syndrome (PCOS) and body mass index-matched controls in a sample of southern Brazilian women. This 8-week randomized trial was carried out at a university gynecological endocrinology clinic and included 18 patients with PCOS and 22 controls. Changes in weight, body composition, hormone, and metabolic profile were analyzed in women randomized to receive HP (30% protein, 40% carbohydrate, and 30% lipid) or NP (15% protein, 55% carbohydrate, and 30% lipid). The energy content was estimated for each participant at 20-25 kcal/kg current weight/day. Physical activity, blood pressure, homeostasis model assessment (HOMA) index, and fasting and 2-h glucose and insulin remained stable during the intervention in PCOS and controls, even in the presence of weight loss. There were no changes in lipid profile in either group. In contrast, body weight, body mass index (BMI), waist circumference, percent of body fat, and sum of trunk skinfolds decreased significantly after both diets in both groups. Total testosterone also decreased in PCOS and controls regardless of diet. In conclusion, calorie reduction, rather than protein content, seemed to affect body composition and hormonal profile in this short-term study. These findings emphasize the role of non-pharmacological interventions to reduce weight and ameliorate the anthropometric and clinical phenotype in PCOS.

Tumor cell surface proteins

International Nuclear Information System (INIS)

Kennel, S.J.; Braslawsky, G.R.; Flynn, K.; Foote, L.J.; Friedman, E.; Hotchkiss, J.A.; Huang, A.H.L.; Lankford, P.K.

1982-01-01

Cell surface proteins mediate interaction between cells and their environment. Unique tumor cell surface proteins are being identified and quantified in several tumor systems to address the following questions: (i) how do tumor-specific proteins arise during cell transformation; (ii) can these proteins be used as markers of tumor cell distribution in vivo; (iii) can cytotoxic drugs be targeted specifically to tumor cells using antibody; and (iv) can solid state radioimmunoassay of these proteins provide a means to quantify transformation frequencies. A tumor surface protein of 180,000 M/sub r/ (TSP-180) has been identified on cells of several lung carcinomas of BALB/c mice. TSP-180 was not detected on normal lung tissue, embryonic tissue, or other epithelial or sarcoma tumors, but it was found on lung carcinomas of other strains of mice. Considerable amino acid sequence homology exists among TSP-180's from several cell sources, indicating that TSP-180 synthesis is directed by normal cellular genes although it is not expressed in normal cells. The regulation of synthesis of TSP-180 and its relationship to normal cell surface proteins are being studied. Monoclonal antibodies (MoAb) to TSP-180 have been developed. The antibodies have been used in immunoaffinity chromatography to isolate TSP-180 from tumor cell sources. This purified tumor antigen was used to immunize rats. Antibody produced by these animals reacted at different sites (epitopes) on the TSP-180 molecule than did the original MoAb. These sera and MoAb from these animals are being used to identify normal cell components related to the TSP-180 molecule

Acrolein-exposed normal human lung fibroblasts in vitro: cellular senescence, enhanced telomere erosion, and degradation of Werner's syndrome protein.

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Jang, Jun-Ho; Bruse, Shannon; Huneidi, Salam; Schrader, Ronald M; Monick, Martha M; Lin, Yong; Carter, A Brent; Klingelhutz, Aloysius J; Nyunoya, Toru

2014-09-01

Acrolein is a ubiquitous environmental hazard to human health. Acrolein has been reported to activate the DNA damage response and induce apoptosis. However, little is known about the effects of acrolein on cellular senescence. We examined whether acrolein induces cellular senescence in cultured normal human lung fibroblasts (NHLF). We cultured NHLF in the presence or absence of acrolein and determined the effects of acrolein on cell proliferative capacity, senescence-associated β-galactosidase activity, the known senescence-inducing pathways (e.g., p53, p21), and telomere length. We found that acrolein induced cellular senescence by increasing both p53 and p21. The knockdown of p53 mediated by small interfering RNA (siRNA) attenuated acrolein-induced cellular senescence. Acrolein decreased Werner's syndrome protein (WRN), a member of the RecQ helicase family involved in DNA repair and telomere maintenance. Acrolein-induced down-regulation of WRN protein was rescued by p53 knockdown or proteasome inhibition. Finally, we found that acrolein accelerated p53-mediated telomere shortening. These results suggest that acrolein induces p53-mediated cellular senescence accompanied by enhanced telomere attrition and WRN protein down-regulation.

Effect of Insulin Infusion on Liver Protein Synthesis during Hemodialysis

DEFF Research Database (Denmark)

Reinhard, Mark; Frystyk, Jan; Jespersen, Bente

2011-01-01

Background Hemodialysis (HD) is a catabolic procedure that may contribute to the high frequency of protein-energy wasting among patients receiving maintenance HD. The present study investigated the additional effect of glucose and glucose-insulin infusion on liver protein synthesis during HD...... compared with a meal alone. Methods In a randomized cross-over study with three arms, 11 non-diabetic HD patients were assigned to receive a conventional HD session with either: • no treatment (NT) • IV infusion of glucose (G) • IV infusion of glucose-insulin (GI) During infusions blood glucose levels were...... maintained at 8.0-10.0 mmol/L by additional glucose infusion. Glucose and glucose-insulin infusions were commenced 2 h prior to HD and continued throughout the HD session. Fasting blood samples were collected at baseline before infusion and followed by the only meal allowed during the study. Results Blood...

Expressão da proteína Bax no tecido mamário normal de mulheres no menacme tratadas com raloxifeno Expression of Bax protein in normal tissue of premenopausal women treated with raloxifene

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Ana Maria Furtado-Veloso

2008-04-01

Full Text Available OBJETIVO: avaliar a expressão do antígeno Bax no epitélio mamário normal de mulheres na pré-menopausa tratadas com raloxifeno. MÉTODOS: estudo randomizado duplo-cego, envolvendo 33 mulheres pré-menopáusicas com fibroadenoma. As pacientes foram divididas em dois grupos: Placebo, (n=18 e Raloxifeno 60 mg, (n=15. A medicação foi usada durante 22 dias, começando no primeiro dia do ciclo menstrual. Uma biópsia foi realizada no 23º dia do ciclo menstrual, durante a qual uma amostra do tecido mamário normal adjacente ao fibroadenoma foi coletada e submetida a estudo imuno-histoquímico utilizando o anticorpo policlonal anti-Bax para avaliar a expressão da proteína Bax. A imunorreação para a proteína Bax foi avaliada, levando-se em consideração a intensidade e a fração de células coradas, cuja combinação resultou em um escore final de 0 a 6. Os casos com escore final >3 foram classificados como positivos para proteína Bax. O teste do c2 foi usado para análise estatística dos dados (pPURPOSE: to evaluate the expression of Bax antigen in the normal mammary epithelium of premenopausal women treated with raloxifene. METHODS: a randomized double-blind study was conducted in 33 ovulatory premenopausal women with fibroadenoma. Patients were divided into two groups: Placebo, (n=18 and Raloxifene 60 mg, (n=15. The medication was used for 22 days, beginning on the first day of the menstrual cycle. An excisional biopsy was carried out on the 23rd day of the menstrual cycle and a sample of normal breast tissue adjacent to the fibroadenoma was collected and submitted to immunohistochemical study using anti-Bax polyclonal antibody to evaluate the expression of Bax protein. Immunoreaction for Bax was evaluated taking into consideration intensity and fraction of stained cells, whose combination resulted in a final score ranging from 0 to 6. Cases with a final score >3 were classified as positive for Bax. The c2 test was used for statistical

The Effect of Oral Leucine on Protein Metabolism in Adolescents with Type 1 Diabetes Mellitus

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Wilson ThomasA

2010-11-01

Full Text Available Lack of insulin results in a catabolic state in subjects with insulin-dependent diabetes mellitus which is reversed by insulin treatment. Amino acid supply, especially branched chain amino acids such as leucine, enhances protein synthesis in both animal and human studies. This small study was undertaken to assess the acute effect of supplemental leucine on protein metabolism in adolescents with type 1 diabetes. L-[1-13C] Leucine was used to assess whole-body protein metabolism in six adolescent females (16–18 yrs with type 1 diabetes during consumption of a basal diet (containing 58 μmoles leucine/kg/h and the basal diet with supplemental leucine (232 μmoles leucine/kg/h. Net leucine balance was significantly higher with supplemental leucine ( μmoles leucine/kg body weight/hr than with the basal diet (, due to reduced protein degradation ( μmoles leucine/kg body weight/hr compared to the basal diet (, .

Organelle-Specific Activity-Based Protein Profiling in Living Cells

Energy Technology Data Exchange (ETDEWEB)

Wiedner, Susan D.; Anderson, Lindsey N.; Sadler, Natalie C.; Chrisler, William B.; Kodali, Vamsi K.; Smith, Richard D.; Wright, Aaron T.

2014-02-06

A multimodal acidic organelle targeting activity-based probe was developed for analysis of subcellular native enzymatic activity of cells by fluorescent microscopy and mass spectrometry. A cathepsin reactive warhead was conjugated to an acidotropic amine, and a clickable alkyne for appendage of AlexaFluor 488 or biotin reporter tags. This probe accumulated in punctate vesicles surrounded by LAMP1, a lysosome marker, as observed by Structured Illumination Microscopy (SIM) in J774 mouse macrophage cells. Biotin conjugation, affinity purification, and analysis of in vivo labeled J774 by mass spectrometry showed that the probe was very selective for Cathepsins B and Z, two lysosomal cysteine proteases. Analysis of starvation induced autophagy, which is an increase in cell component catabolism involving lysosomes, showed a large increase in tagged protein number and an increase in cathepsin activity. Organelle targeting activity-based probes and subsequent analysis of resident proteins by mass spectrometry is enabled by tuning the physicochemical properties of the probe.

CSF total protein

Science.gov (United States)

CSF total protein is a test to determine the amount of protein in your spinal fluid, also called cerebrospinal fluid (CSF). ... The normal protein range varies from lab to lab, but is typically about 15 to 60 milligrams per deciliter (mg/dL) ...

Fatty acid-binding proteins (FABPs) are intracellular carriers for Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD).

Science.gov (United States)

Elmes, Matthew W; Kaczocha, Martin; Berger, William T; Leung, KwanNok; Ralph, Brian P; Wang, Liqun; Sweeney, Joseph M; Miyauchi, Jeremy T; Tsirka, Stella E; Ojima, Iwao; Deutsch, Dale G

2015-04-03

Δ(9)-Tetrahydrocannabinol (THC) and cannabidiol (CBD) occur naturally in marijuana (Cannabis) and may be formulated, individually or in combination in pharmaceuticals such as Marinol or Sativex. Although it is known that these hydrophobic compounds can be transported in blood by albumin or lipoproteins, the intracellular carrier has not been identified. Recent reports suggest that CBD and THC elevate the levels of the endocannabinoid anandamide (AEA) when administered to humans, suggesting that phytocannabinoids target cellular proteins involved in endocannabinoid clearance. Fatty acid-binding proteins (FABPs) are intracellular proteins that mediate AEA transport to its catabolic enzyme fatty acid amide hydrolase (FAAH). By computational analysis and ligand displacement assays, we show that at least three human FABPs bind THC and CBD and demonstrate that THC and CBD inhibit the cellular uptake and catabolism of AEA by targeting FABPs. Furthermore, we show that in contrast to rodent FAAH, CBD does not inhibit the enzymatic actions of human FAAH, and thus FAAH inhibition cannot account for the observed increase in circulating AEA in humans following CBD consumption. Using computational molecular docking and site-directed mutagenesis we identify key residues within the active site of FAAH that confer the species-specific sensitivity to inhibition by CBD. Competition for FABPs may in part or wholly explain the increased circulating levels of endocannabinoids reported after consumption of cannabinoids. These data shed light on the mechanism of action of CBD in modulating the endocannabinoid tone in vivo and may explain, in part, its reported efficacy toward epilepsy and other neurological disorders. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

Bioinformatic evaluation of L-arginine catabolic pathways in 24 cyanobacteria and transcriptional analysis of genes encoding enzymes of L-arginine catabolism in the cyanobacterium Synechocystis sp. PCC 6803

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Pistorius Elfriede K

2007-11-01

Full Text Available Abstract Background So far very limited knowledge exists on L-arginine catabolism in cyanobacteria, although six major L-arginine-degrading pathways have been described for prokaryotes. Thus, we have performed a bioinformatic analysis of possible L-arginine-degrading pathways in cyanobacteria. Further, we chose Synechocystis sp. PCC 6803 for a more detailed bioinformatic analysis and for validation of the bioinformatic predictions on L-arginine catabolism with a transcript analysis. Results We have evaluated 24 cyanobacterial genomes of freshwater or marine strains for the presence of putative L-arginine-degrading enzymes. We identified an L-arginine decarboxylase pathway in all 24 strains. In addition, cyanobacteria have one or two further pathways representing either an arginase pathway or L-arginine deiminase pathway or an L-arginine oxidase/dehydrogenase pathway. An L-arginine amidinotransferase pathway as a major L-arginine-degrading pathway is not likely but can not be entirely excluded. A rather unusual finding was that the cyanobacterial L-arginine deiminases are substantially larger than the enzymes in non-photosynthetic bacteria and that they are membrane-bound. A more detailed bioinformatic analysis of Synechocystis sp. PCC 6803 revealed that three different L-arginine-degrading pathways may in principle be functional in this cyanobacterium. These are (i an L-arginine decarboxylase pathway, (ii an L-arginine deiminase pathway, and (iii an L-arginine oxidase/dehydrogenase pathway. A transcript analysis of cells grown either with nitrate or L-arginine as sole N-source and with an illumination of 50 μmol photons m-2 s-1 showed that the transcripts for the first enzyme(s of all three pathways were present, but that the transcript levels for the L-arginine deiminase and the L-arginine oxidase/dehydrogenase were substantially higher than that of the three isoenzymes of L-arginine decarboxylase. Conclusion The evaluation of 24

Methyl salicylate-induced arginine catabolism is associated with up-regulation of polyamine and nitric oxide levels and improves chilling tolerance in cherry tomato fruit.

Science.gov (United States)

Zhang, Xinhua; Shen, Lin; Li, Fujun; Meng, Demei; Sheng, Jiping

2011-09-14

The effects of methyl salicylate (MeSA) on chilling injury (CI) and gene expression levels, enzyme activities, and metabolites related to arginine catabolism in cherry tomato fruit were investigated. Freshly harvested fruits were treated with 0.05 mM MeSA vapor at 20 °C for 12 h and then stored at 2 °C for up to 28 days. MeSA reduced CI and enhanced the accumulation of putrescine, spermidine, and spermine, which was associated with increased gene expression levels and activities of arginase, arginine decarboxylase, and ornithine decarboxylase at most sampling times. MeSA also increased nitric oxide synthase activity, which at least partly contributed to the increased nitric oxide content. The results indicate that MeSA activates the different pathways of arginine catabolism in cold-stored fruit and that the reduction in CI by MeSA may be due to the coordinated metabolism of arginine and the increase in polyamines and nitric oxide levels.

Bacteria of the human gut microbiome catabolize red seaweed glycans with carbohydrate-active enzyme updates from extrinsic microbes.

Science.gov (United States)

Hehemann, Jan-Hendrik; Kelly, Amelia G; Pudlo, Nicholas A; Martens, Eric C; Boraston, Alisdair B

2012-11-27

Humans host an intestinal population of microbes--collectively referred to as the gut microbiome--which encode the carbohydrate active enzymes, or CAZymes, that are absent from the human genome. These CAZymes help to extract energy from recalcitrant polysaccharides. The question then arises as to if and how the microbiome adapts to new carbohydrate sources when modern humans change eating habits. Recent metagenome analysis of microbiomes from healthy American, Japanese, and Spanish populations identified putative CAZymes obtained by horizontal gene transfer from marine bacteria, which suggested that human gut bacteria evolved to degrade algal carbohydrates-for example, consumed in form of sushi. We approached this hypothesis by studying such a polysaccharide utilization locus (PUL) obtained by horizontal gene transfer by the gut bacterium Bacteroides plebeius. Transcriptomic and growth experiments revealed that the PUL responds to the polysaccharide porphyran from red algae, enabling growth on this carbohydrate but not related substrates like agarose and carrageenan. The X-ray crystallographic and biochemical analysis of two proteins encoded by this PUL, BACPLE_01689 and BACPLE_01693, showed that they are β-porphyranases belonging to glycoside hydrolase families 16 and 86, respectively. The product complex of the GH86 at 1.3 Å resolution highlights the molecular details of porphyran hydrolysis by this new porphyranase. Combined, these data establish experimental support for the argument that CAZymes and associated genes obtained from extrinsic microbes add new catabolic functions to the human gut microbiome.

Emerging connections between RNA and autophagy

DEFF Research Database (Denmark)

Frankel, Lisa B; Lubas, Michal; Lund, Anders H

2017-01-01

in yeast, plants and animals, reviewing the molecular mechanisms and biological importance in normal physiology, stress and disease. In addition, we explore emerging evidence of core autophagy regulation mediated by RNA-binding proteins and noncoding RNAs, and point to gaps in our current knowledge......Macroautophagy/autophagy is a key catabolic process, essential for maintaining cellular homeostasis and survival through the removal and recycling of unwanted cellular material. Emerging evidence has revealed intricate connections between the RNA and autophagy research fields. While a majority...... of the connection between RNA and autophagy. Finally, we discuss the pathological implications of RNA-protein aggregation, primarily in the context of neurodegenerative disease....

On the sensitivity of protein data bank normal mode analysis: an application to GH10 xylanases

Science.gov (United States)

Tirion, Monique M.

2015-12-01

Protein data bank entries obtain distinct, reproducible flexibility characteristics determined by normal mode analyses of their three dimensional coordinate files. We study the effectiveness and sensitivity of this technique by analyzing the results on one class of glycosidases: family 10 xylanases. A conserved tryptophan that appears to affect access to the active site can be in one of two conformations according to x-ray crystallographic electron density data. The two alternate orientations of this active site tryptophan lead to distinct flexibility spectra, with one orientation thwarting the oscillations seen in the other. The particular orientation of this sidechain furthermore affects the appearance of the motility of a distant, C terminal region we term the mallet. The mallet region is known to separate members of this family of enzymes into two classes.

On the sensitivity of protein data bank normal mode analysis: an application to GH10 xylanases

International Nuclear Information System (INIS)

Tirion, Monique M

2015-01-01

Protein data bank entries obtain distinct, reproducible flexibility characteristics determined by normal mode analyses of their three dimensional coordinate files. We study the effectiveness and sensitivity of this technique by analyzing the results on one class of glycosidases: family 10 xylanases. A conserved tryptophan that appears to affect access to the active site can be in one of two conformations according to x-ray crystallographic electron density data. The two alternate orientations of this active site tryptophan lead to distinct flexibility spectra, with one orientation thwarting the oscillations seen in the other. The particular orientation of this sidechain furthermore affects the appearance of the motility of a distant, C terminal region we term the mallet. The mallet region is known to separate members of this family of enzymes into two classes. (paper)

The role of HBV-induced autophagy in HBV replication and HBV related-HCC.

Science.gov (United States)

Xie, Mingjie; Yang, Zhenggang; Liu, Yanning; Zheng, Min

2018-04-27

Hepatitis B virus (HBV) is infecting about 364 million people around the world. It can cause various diseases, such as chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma (HCC). However, the present anti-viral treatment in clinics is limited; studies for new therapies are highly desired. Autophagy is a crucial and major catabolic process in the maintenance of normal intracellular homeostasis in host cells. Host cells use this unique process to degrade and recycle long-lived proteins, damaged organelles, and various pathogens for keeping the normal physiological functions. Recently, published studies indicated that HBV can induce autophagy in host cells; this autophagic response is involved in viral replication and pathogenesis. Several viral proteins, such as surface and X proteins, are assumed to be responsible for inducing autophagy in HBV infection. This review briefly summarizes some important mechanisms involved in HBV-induced autophagy and provides a novel perspective on therapies of HBV infection and HBV-related HCC. Copyright © 2017. Published by Elsevier Inc.

Heat shock proteins of higher plants

International Nuclear Information System (INIS)

Key, J.L.; Lin, C.Y.; Chen, Y.M.

1981-01-01

The pattern of protein synthesis changes rapidly and dramatically when the growth temperture of soybean seedling tissue is increased from 28 0 C (normal) to about 40 0 C (heat shock). The synthesis of normal proteins is greatly decreased and a new set of proteins, heat shock proteins, is induced. The heat shock proteins of soybean consist of 10 new bands on one-dimensional NaDodSO 4 gels; a more complex pattern is observed on two-dimensional gels. when the tissue is returned to 28 0 C after 4 hr at 40 0 C, there is progressive decline in the synthesis of heat shock proteins and reappearance of a normal pattern of synthesis by 3 or 4 hr. In vitro translation of poly(A) + RNAs isolated from tissued grown at 28 and 40 0 C shows that the heat shock proteins are translated from a ndw set of mRNAs induced at 40 0 C; furthermore, the abundant class mRNAs for many of the normal proteins persist even though they are translated weakly (or not at all) in vivo at 40 or 42.5 0 C. The heat shock response in soybean appears similar to the much-studied heat shock phenomenon in Drosophila

Autophagy-Associated Protein SmATG12 Is Required for Fruiting-Body Formation in the Filamentous Ascomycete Sordaria macrospora.

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Werner, Antonia; Herzog, Britta; Frey, Stefan; Pöggeler, Stefanie

2016-01-01

In filamentous fungi, autophagy functions as a catabolic mechanism to overcome starvation and to control diverse developmental processes under normal nutritional conditions. Autophagy involves the formation of double-membrane vesicles, termed autophagosomes that engulf cellular components and bring about their degradation via fusion with vacuoles. Two ubiquitin-like (UBL) conjugation systems are essential for the expansion of the autophagosomal membrane: the UBL protein ATG8 is conjugated to the lipid phosphatidylethanolamine and the UBL protein ATG12 is coupled to ATG5. We recently showed that in the homothallic ascomycete Sordaria macrospora autophagy-related genes encoding components of the conjugation systems are required for fruiting-body development and/or are essential for viability. In the present work, we cloned and characterized the S. macrospora (Sm)atg12 gene. Two-hybrid analysis revealed that SmATG12 can interact with SmATG7 and SmATG3. To examine its role in S. macrospora, we replaced the open reading frame of Smatg12 with a hygromycin resistance cassette and generated a homokaryotic ΔSmatg12 knockout strain, which displayed slower vegetative growth under nutrient starvation conditions and was unable to form fruiting bodies. In the hyphae of S. macrospora EGFP-labeled SmATG12 was detected in the cytoplasm and as punctate structures presumed to be phagophores or phagophore assembly sites. Delivery of EGFP-labelled SmATG8 to the vacuole was entirely dependent on SmATG12.

Autophagy-Associated Protein SmATG12 Is Required for Fruiting-Body Formation in the Filamentous Ascomycete Sordaria macrospora.

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Antonia Werner

Full Text Available In filamentous fungi, autophagy functions as a catabolic mechanism to overcome starvation and to control diverse developmental processes under normal nutritional conditions. Autophagy involves the formation of double-membrane vesicles, termed autophagosomes that engulf cellular components and bring about their degradation via fusion with vacuoles. Two ubiquitin-like (UBL conjugation systems are essential for the expansion of the autophagosomal membrane: the UBL protein ATG8 is conjugated to the lipid phosphatidylethanolamine and the UBL protein ATG12 is coupled to ATG5. We recently showed that in the homothallic ascomycete Sordaria macrospora autophagy-related genes encoding components of the conjugation systems are required for fruiting-body development and/or are essential for viability. In the present work, we cloned and characterized the S. macrospora (Smatg12 gene. Two-hybrid analysis revealed that SmATG12 can interact with SmATG7 and SmATG3. To examine its role in S. macrospora, we replaced the open reading frame of Smatg12 with a hygromycin resistance cassette and generated a homokaryotic ΔSmatg12 knockout strain, which displayed slower vegetative growth under nutrient starvation conditions and was unable to form fruiting bodies. In the hyphae of S. macrospora EGFP-labeled SmATG12 was detected in the cytoplasm and as punctate structures presumed to be phagophores or phagophore assembly sites. Delivery of EGFP-labelled SmATG8 to the vacuole was entirely dependent on SmATG12.

Cofactor balance by nicotinamide nucleotide transhydrogenase (NNT) coordinates reductive carboxylation and glucose catabolism in the tricarboxylic acid (TCA) cycle.

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Gameiro, Paulo A; Laviolette, Laura A; Kelleher, Joanne K; Iliopoulos, Othon; Stephanopoulos, Gregory

2013-05-03

Cancer and proliferating cells exhibit an increased demand for glutamine-derived carbons to support anabolic processes. In addition, reductive carboxylation of α-ketoglutarate by isocitrate dehydrogenase 1 (IDH1) and 2 (IDH2) was recently shown to be a major source of citrate synthesis from glutamine. The role of NAD(P)H/NAD(P)(+) cofactors in coordinating glucose and glutamine utilization in the tricarboxylic acid (TCA) cycle is not well understood, with the source(s) of NADPH for the reductive carboxylation reaction remaining unexplored. Nicotinamide nucleotide transhydrogenase (NNT) is a mitochondrial enzyme that transfers reducing equivalents from NADH to NADPH. Here, we show that knockdown of NNT inhibits the contribution of glutamine to the TCA cycle and activates glucose catabolism in SkMel5 melanoma cells. The increase in glucose oxidation partially occurred through pyruvate carboxylase and rendered NNT knockdown cells more sensitive to glucose deprivation. Importantly, knocking down NNT inhibits reductive carboxylation in SkMel5 and 786-O renal carcinoma cells. Overexpression of NNT is sufficient to stimulate glutamine oxidation and reductive carboxylation, whereas it inhibits glucose catabolism in the TCA cycle. These observations are supported by an impairment of the NAD(P)H/NAD(P)(+) ratios. Our findings underscore the role of NNT in regulating central carbon metabolism via redox balance, calling for other mechanisms that coordinate substrate preference to maintain a functional TCA cycle.

Improved sugar-free succinate production by Synechocystis sp. PCC 6803 following identification of the limiting steps in glycogen catabolism

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Tomohisa Hasunuma

2016-12-01

Full Text Available Succinate produced by microorganisms can replace currently used petroleum-based succinate but typically requires mono- or poly-saccharides as a feedstock. The cyanobacterium Synechocystis sp. PCC6803 can produce organic acids such as succinate from CO2 not supplemented with sugars under dark anoxic conditions using an unknown metabolic pathway. The TCA cycle in cyanobacteria branches into oxidative and reductive routes. Time-course analyses of the metabolome, transcriptome and metabolic turnover described here revealed dynamic changes in the metabolism of Synechocystis sp. PCC6803 cultivated under dark anoxic conditions, allowing identification of the carbon flow and rate-limiting steps in glycogen catabolism. Glycogen biosynthesized from CO2 assimilated during periods of light exposure is catabolized to succinate via glycolysis, the anaplerotic pathway, and the reductive TCA cycle under dark anoxic conditions. Expression of the phosphoenolpyruvate (PEP carboxylase gene (ppc was identified as a rate-limiting step in succinate biosynthesis and this rate limitation was alleviated by ppc overexpression, resulting in improved succinate excretion. The sugar-free succinate production was further enhanced by the addition of bicarbonate. In vivo labeling with NaH13CO3 clearly showed carbon incorporation into succinate via the anaplerotic pathway. Bicarbonate is in equilibrium with CO2. Succinate production by Synechocystis sp. PCC6803 therefore holds significant promise for CO2 capture and utilization. Keywords: Autofermentation, Cyanobacteria, Dynamic metabolic profiling, Metabolomics, Succinate, Synechocystis

Biodegradation Ability and Catabolic Genes of Petroleum-Degrading Sphingomonas koreensis Strain ASU-06 Isolated from Egyptian Oily Soil

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Abd El-Latif Hesham

2014-01-01

Full Text Available Polycyclic aromatic hydrocarbons (PAHs are serious pollutants and health hazards. In this study, 15 PAHs-degrading bacteria were isolated from Egyptian oily soil. Among them, one Gram-negative strain (ASU-06 was selected and biodegradation ability and initial catabolic genes of petroleum compounds were investigated. Comparison of 16S rRNA gene sequence of strain ASU-06 to published sequences in GenBank database as well as phylogenetic analysis identified ASU-06 as Sphingomonas koreensis. Strain ASU-06 degraded 100, 99, 98, and 92.7% of 100 mg/L naphthalene, phenanthrene, anthracene, and pyrene within 15 days, respectively. When these PAHs present in a mixed form, the enhancement phenomenon appeared, particularly in the degradation of pyrene, whereas the degradation rate was 98.6% within the period. This is the first report showing the degradation of different PAHs by this species. PCR experiments with specific primers for catabolic genes alkB, alkB1, nahAc, C12O, and C23O suggested that ASU-06 might possess genes for aliphatic and PAHs degradation, while PAH-RHDαGP gene was not detected. Production of biosurfactants and increasing cell-surface hydrophobicity were investigated. GC/MS analysis of intermediate metabolites of studied PAHs concluded that this strain utilized these compounds via two main pathways, and phthalate was the major constant product that appeared in each day of the degradation period.

Protein turnover in malnourished patients with cystic fibrosis: Effects of elemental and nonelemental nutritional supplements

International Nuclear Information System (INIS)

Pelekanos, J.T.; Holt, T.L.; Ward, L.C.; Cleghorn, G.J.; Shepherd, R.W.

1990-01-01

To evaluate the relative efficacy of nonelemental versus semielemental enteral supplements for nutritional rehabilitation of cystic fibrosis (CF) patients, whole-body protein turnover using the [ 15 N]glycine method was studied in nine malnourished CF patients during enteral feedings, in a block design study comparing a semielemental formula (Criticare), a higher protein density but nonelemental formula (Traumacal) (T), and a nonelemental formula that had been modified to become isocaloric and isonitrogenous to the semielemental formula (modified Traumacal, MT). No significant differences in rates of protein synthesis or catabolism were observed comparing the three formulas. However, the higher protein density nonelemental formula resulted in higher net protein deposition compared to the other two formulas (T + 0.42 g kg-1 10 h-1 versus 0.33 g kg-1 10 h-1 for Criticare and -0.59 g kg-1 10 h-1 for MT), although this was significant (p less than 0.05) for the MT versus T comparison only. This study lends support to the use of less expensive nonelemental formulas for the nutritional management of malnourished patients with CF

Urea recycling contributes to nitrogen retention in calves fed milk replacer and low-protein solid feed

DEFF Research Database (Denmark)

Berends, Harma; van den Borne, Joost J G C; Røjen, Betina A.

2014-01-01

Urea recycling, with urea originating from catabolism of amino acids and hepatic detoxification of ammonia, is particularly relevant for ruminant animals, in which microbial protein contributes substantially to the metabolizable protein supply. However, the quantitative contribution of urea...... recycling to protein anabolism in calves during the transition from preruminants (milk-fed calves) to ruminants [solid feed (SF)-fed calves] is unknown. The aim of this study was to quantify urea recycling in milk-fed calves when provided with low-protein SF. Forty-eight calves [164 ± 1.6 kg body weight (BW......)] were assigned to 1 of 4 SF levels [0, 9, 18, and 27 g of dry matter (DM) SF · kg BW2-0.75 . d-1] provided in addition to an identical amount of milk replacer. Urea recycling was quantified after a 24-h intravenous infusion of [15N2]urea by analyzing urea isotopomers in 68-h fecal and urinary...

Biodistribution and catabolism of {sup 18}F-labeled N-{epsilon}-fructoselysine as a model of Amadori products

Energy Technology Data Exchange (ETDEWEB)

Hultsch, Christina [Institute of Radiopharmacy, Research Center Rossendorf, P.O. Box 51 01 19, D-01314 Dresden (Germany); Hellwig, Michael [Institute of Food Chemistry, Technische Universitaet Dresden, D-01062 Dresden (Germany); Pawelke, Beate [Institute of Radiopharmacy, Research Center Rossendorf, P.O. Box 51 01 19, D-01314 Dresden (Germany); Bergmann, Ralf [Institute of Radiopharmacy, Research Center Rossendorf, P.O. Box 51 01 19, D-01314 Dresden (Germany); Rode, Katrin [Institute of Radiopharmacy, Research Center Rossendorf, P.O. Box 51 01 19, D-01314 Dresden (Germany); Pietzsch, Jens [Institute of Radiopharmacy, Research Center Rossendorf, P.O. Box 51 01 19, D-01314 Dresden (Germany); Krause, Rene [Institute of Food Chemistry, Technische Universitaet Dresden, D-01062 Dresden (Germany); Henle, Thomas [Institute of Food Chemistry, Technische Universitaet Dresden, D-01062 Dresden (Germany)

2006-10-15

Amadori products are formed in the early stage of the so-called Maillard reaction between reducing sugars and amino acids or proteins. Such nonenzymatic glycosylation may occur during the heating or storage of foods, but also under physiological conditions. N-{epsilon}-fructoselysine is formed via this reaction between the {epsilon}-amino group of peptide-bound lysine and glucose. Despite the fact that, in certain heated foods, up to 50% of lysyl moieties may be modified to such lysine derivatives, up to now, very little is known about the metabolic fate of alimentary administered Amadori compounds. In the present study, N-succinimidyl-4-[{sup 18}F]fluorobenzoate was used to modify N-{epsilon}-fructoselysine at the {alpha}-amino group of the lysyl moiety. The in vitro stability of the resulting 4-[{sup 18}F]fluorobenzoylated derivative was tested in different tissue homogenates. Furthermore, the 4-[{sup 18}F]fluorobenzoylated N-{epsilon}-fructoselysine was used in positron emission tomography studies, as well as in studies concerning biodistribution and catabolism. The results show that the 4-[{sup 18}F]fluorobenzoylated N-{epsilon}-fructoselysine is phosphorylated in vitro, as well as in vivo. This phosphorylation is caused by fructosamine 3-kinases and occurs in vivo, particularly in the kidneys. Despite the action of these enzymes, it was shown that a large part of the intravenously applied radiolabeled N-{epsilon}-fructoselysine was excreted nearly unchanged in the urine. Therefore, it was concluded that the predominant part of peptide-bound lysine that was fructosylated during food processing is not available for nutrition.

Common catabolic enzyme patterns in a microplankton community of the Humboldt Current System off northern and central-south Chile: Malate dehydrogenase activity as an index of water-column metabolism in an oxygen minimum zone

Science.gov (United States)

González, R. R.; Quiñones, R. A.

2009-07-01

An extensive subsurface oxygen minimum zone off northern and central-south Chile, associated with the Peru-Chile undercurrent, has important effects on the metabolism of the organisms inhabiting therein. Planktonic species deal with the hypoxic and anoxic environments by relying on biochemical as well as physiological processes related to their anaerobic metabolisms. Here we characterize, for the first time, the potential enzymatic activities involved in the aerobic and anaerobic energy production pathways of microplanktonic organisms (oxygen concentration and microplanktonic biomass in the oxygen minimum zone and adjacent areas of the Humboldt Current System water column. Our results demonstrate significant potential enzymatic activity of catabolic pathways in the oxygen minimum zone. Malate dehydrogenase had the highest oxidizing activity of nicotinamide adenine dinucleotide (reduced form) in the batch of catabolic enzymatic activities assayed, including potential pyruvate oxidoreductases activity, the electron transport system, and dissimilatory nitrate reductase. Malate dehydrogenase correlated significantly with almost all the enzymes analyzed within and above the oxygen minimum zone, and also with the oxygen concentration and microplankton biomass in the water column of the Humboldt Current System, especially in the oxygen minimum zone off Iquique. These results suggest a possible specific pattern for the catabolic activity of the microplanktonic realm associated with the oxygen minimum zone spread along the Humboldt Current System off Chile. We hypothesize that malate dehydrogenase activity could be an appropriate indicator of microplankton catabolism in the oxygen minimum zone and adjacent areas.

Fatty acid profile of maternal and fetal erythrocytes and placental expression of fatty acid transport proteins in normal and intrauterine growth restriction pregnancies.

Science.gov (United States)

Assumpção, Renata P; Mucci, Daniela B; Fonseca, Fernanda C P; Marcondes, Henrique; Sardinha, Fátima L C; Citelli, Marta; Tavares do Carmo, Maria G

2017-10-01

Long-chain polyunsaturated fatty acids (LC-PUFA), mainly docosahexaenoic (DHA) and arachidonic acids (AA), are critical for adequate fetal growth and development. We investigated mRNA expression of proteins involved in hydrolysis, uptake and/or transport of fatty acids in placenta of fifteen full term normal pregnancies and eleven pregnancies complicated by intrauterine growth restriction (IUGR) with normal umbilical blood flows. The mRNA expression of LPL, FATPs (-1, -2 and -4) and FABPs (-1 and -3) was increased in IUGR placentas, however, tissue profile of LC-PUFA was not different between groups. Erythrocytes from both mothers and fetuses of the IUGR group showed lower concentrations of AA and DHA and inferior DHA/ALA ratio compared to normal pregnancies (P < 0.05). We hypothesize that reduced circulating levels of AA and DHA could up-regulate mRNA expression of placental fatty acids transporters, as a compensatory mechanism, however this failed to sustain normal LC-PUFA supply to the fetus in IUGR. Copyright © 2017 Elsevier Ltd. All rights reserved.

Protein turnover and 3-methylhistidine excretion in non-pregnant, pregnant and gestational diabetic women

International Nuclear Information System (INIS)

Fitch, W.L.; King, J.C.

1986-01-01

Protein turnover was studied in nine non-pregnant (NP) women, eight pregnant (P) and two gestational diabetic (GDM) women. Whole body protein turnover, synthesis and catabolism rates were measured using a single oral dose of 15 N-glycine followed by measurement of enrichment of urinary ammonia. Urinary 3-methylhistidine (3MH) excretion was measured for three consecutive days, including the day of the protein turnover study. Whole body protein turnover and synthesis rates did not differ between the P and NP women, although the synthesis rates tended to be higher in the P group. Gestational diabetic women appeared to have considerably higher rates of both turnover and synthesis. Pregnant women excreted significantly more urinary 3MH than did non-pregnant women. GDM women appeared to have lower 3MH excretion than the P women. Correlation between 3MH excretion and protein turnover rates was nearly significant (p = .06) in the NP women, but was poorly correlated (p = .43) in the P women, suggesting that muscles may be a less important site of whole body protein turnover in pregnancy than in the non-pregnant state

Comparative proteomics of Rhizopus delemar ATCC 20344 unravels the role of amino acid catabolism in fumarate accumulation

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Dorett I. Odoni

2017-03-01

Full Text Available The filamentous fungus Rhizopus delemar naturally accumulates relatively high amounts of fumarate. Although the culture conditions that increase fumarate yields are well established, the network underlying the accumulation of fumarate is not yet fully understood. We set out to increase the knowledge about fumarate accumulation in R. delemar. To this end, we combined a transcriptomics and proteomics approach to identify key metabolic pathways involved in fumarate production in R. delemar, and propose that a substantial part of the fumarate accumulated in R. delemar during nitrogen starvation results from the urea cycle due to amino acid catabolism.

Complete nucleotide sequence of the self-transmissible TOL plasmid pD2RT provides new insight into arrangement of toluene catabolic plasmids

DEFF Research Database (Denmark)

Jutkina, Jekaterina; Hansen, Lars Hestbjerg; Li, Lili

2013-01-01

In the present study we report the complete nucleotide sequence of the toluene catabolic plasmid pD2RT of Pseudomonas migulae strain D2RT isolated from Baltic Sea water. The pD2RT is 129,894 base pairs in size with an average G+ C content of 53.75%. A total of 135 open reading frames (ORFs) were ...

Dietary supplementation of branched-chain amino acids increases muscle net amino acid fluxes through elevating their substrate availability and intramuscular catabolism in young pigs.

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Zheng, Liufeng; Zuo, Fangrui; Zhao, Shengjun; He, Pingli; Wei, Hongkui; Xiang, Quanhang; Pang, Jiaman; Peng, Jian

2017-04-01

Branched-chain amino acids (BCAA) have been clearly demonstrated to have anabolic effects on muscle protein synthesis. However, little is known about their roles in the regulation of net AA fluxes across skeletal muscle in vivo. This study was aimed to investigate the effect and related mechanisms of dietary supplementation of BCAA on muscle net amino acid (AA) fluxes using the hindlimb flux model. In all fourteen 4-week-old barrows were fed reduced-protein diets with or without supplemental BCAA for 28 d. Pigs were implanted with carotid arterial, femoral arterial and venous catheters, and fed once hourly with intraarterial infusion of p-amino hippurate. Arterial and venous plasma and muscle samples were obtained for the measurement of AA, branched-chain α-keto acids (BCKA) and 3-methylhistidine (3-MH). Metabolomes of venous plasma were determined by HPLC-quadrupole time-of-flight-MS. BCAA-supplemented group showed elevated muscle net fluxes of total essential AA, non-essential AA and AA. As for individual AA, muscle net fluxes of each BCAA and their metabolites (alanine, glutamate and glutamine), along with those of histidine, methionine and several functional non-essential AA (glycine, proline and serine), were increased by BCAA supplementation. The elevated muscle net AA fluxes were associated with the increase in arterial and intramuscular concentrations of BCAA and venous metabolites including BCKA and free fatty acids, and were also related to the decrease in the intramuscular concentration of 3-MH. Correlation analysis indicated that muscle net AA fluxes are highly and positively correlated with arterial BCAA concentrations and muscle net BCKA production. In conclusion, supplementing BCAA to reduced-protein diet increases the arterial concentrations and intramuscular catabolism of BCAA, both of which would contribute to an increase of muscle net AA fluxes in young pigs.

Multi-scaled normal mode analysis method for dynamics simulation of protein-membrane complexes: A case study of potassium channel gating motion correlations

Energy Technology Data Exchange (ETDEWEB)

Wu, Xiaokun; Han, Min; Ming, Dengming, E-mail: dming@fudan.edu.cn [Department of Physiology and Biophysics, School of Life Sciences, Fudan University, Shanghai (China)

2015-10-07

Membrane proteins play critically important roles in many cellular activities such as ions and small molecule transportation, signal recognition, and transduction. In order to fulfill their functions, these proteins must be placed in different membrane environments and a variety of protein-lipid interactions may affect the behavior of these proteins. One of the key effects of protein-lipid interactions is their ability to change the dynamics status of membrane proteins, thus adjusting their functions. Here, we present a multi-scaled normal mode analysis (mNMA) method to study the dynamics perturbation to the membrane proteins imposed by lipid bi-layer membrane fluctuations. In mNMA, channel proteins are simulated at all-atom level while the membrane is described with a coarse-grained model. mNMA calculations clearly show that channel gating motion can tightly couple with a variety of membrane deformations, including bending and twisting. We then examined bi-channel systems where two channels were separated with different distances. From mNMA calculations, we observed both positive and negative gating correlations between two neighboring channels, and the correlation has a maximum as the channel center-to-center distance is close to 2.5 times of their diameter. This distance is larger than recently found maximum attraction distance between two proteins embedded in membrane which is 1.5 times of the protein size, indicating that membrane fluctuation might impose collective motions among proteins within a larger area. The hybrid resolution feature in mNMA provides atomic dynamics information for key components in the system without costing much computer resource. We expect it to be a conventional simulation tool for ordinary laboratories to study the dynamics of very complicated biological assemblies. The source code is available upon request to the authors.

Addiction to Coupling of the Warburg Effect with Glutamine Catabolism in Cancer Cells

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Bradley Smith

2016-10-01

Full Text Available Metabolic reprogramming is critical to oncogenesis, but the emergence and function of this profound reorganization remain poorly understood. Here we find that cooperating oncogenic mutations drive large-scale metabolic reprogramming, which is both intrinsic to cancer cells and obligatory for the transition to malignancy. This involves synergistic regulation of several genes encoding metabolic enzymes, including the lactate dehydrogenases LDHA and LDHB and mitochondrial glutamic pyruvate transaminase 2 (GPT2. Notably, GPT2 engages activated glycolysis to drive the utilization of glutamine as a carbon source for TCA cycle anaplerosis in colon cancer cells. Our data indicate that the Warburg effect supports oncogenesis via GPT2-mediated coupling of pyruvate production to glutamine catabolism. Although critical to the cancer phenotype, GPT2 activity is dispensable in cells that are not fully transformed, thus pinpointing a metabolic vulnerability specifically associated with cancer cell progression to malignancy.

Effect of dietary protein on the excretion of. cap alpha. /sub 2u/, the sex-dependent protein of the adult male rat

Energy Technology Data Exchange (ETDEWEB)

Neuhaus, O W; Flory, W

1975-01-01

Adult male rates were maintained on normal (20 percent casein), protein-free (0 percent casein), high protein (50 percent casein), deficient protein (20 percent zein), and a supplemented, deficient protein (20 percent zein plus L-lysine and L-tryptophan) diets. Rats on a protein-free diet excreted approximately 1 mg ..cap alpha../sub 2u//24 h compared with a normal of 10-15 mg/24 h. Depleted rats placed on the normal diet showed a rapid restoration of the normal ..cap alpha../sub 2u/ excretion as well as total urinary proteins. Accumulation of ..cap alpha../sub 2u/ in the blood serum was measured in nephrectomized rats. Rats on the protein free diet accumulated only 30 percent of the ..cap alpha../sub 2u/ compared to normals. On a 50 precent casein diet, rats excreted 30-50 mg ..cap alpha../sub 2u//24 h. However, the accumulation was normal in the serum of nephrectomized rats. A high protein diet did not stimulate ..cap alpha../sub 2u/ synthesis but probably increased the renal loss of all urinary proteins. The excretion of ..cap alpha../sub 2u/ on a zein diet was reduced to the same degree as with the protein-free diet. Supplementation with lysine and tryptophan restored the capacity to eliminate ..cap alpha../sub 2u/ to near normal levels. Accumulation of ..cap alpha../sub 2u/ in the serum of nephrectomized rats kept on the zein diets showed that the effect was to suppress the synthesis of the ..cap alpha../sub 2u/. Supplementation restored the biosynthesis of ..cap alpha../sub 2u/. It is concluded that the effect of dietary protein on the excretion of urinary proteins in the adult male rat is caused in a large part by an influence on the hepatic biosynthesis of ..cap alpha../sub 2u/. The biosynthesis of this protein, which represents approximately 30 percent of the total urinary proteins, is dependent on an adequate supply of dietary protein.

Metabolism features in the active rheumatoid disease

Energy Technology Data Exchange (ETDEWEB)

Cossermelli, W; Carvalho, N; Papaleo Netto, M [Sao Paulo Univ. (Brazil). Centro de Medicina Nuclear

1974-02-01

The /sup 131/I-labelled albumin metabolism was studied in fourteen female patients with rheumatoid arthritis. The half-life of distribution was increased while the turnover half-life and turnover rate was within normal limits. These results led to assume that synthesis and catabolism may not change this disease, not being the responsible mechanism of hypoalbuminemia. Hypoalbuminemia would appear as compensatory mechanism in view of other protein alterations, as hypergammaglobulinemia, without changes of stabilizing and metabolic properties of albumin, perhaps due to albumin molecular alterations.

Metabolism features in the active rheumatoid disease

International Nuclear Information System (INIS)

Cossermelli, W.; Carvalho, N.; Papaleo Netto, M.

1974-01-01

It was studied the 131 I-labelled albumin metabolism in fourteen female patients with rheumatoid arthritis. The half-life of distribution was increased while the turnover half-life and turnover rate was within normal limits. These results led to assume that synthesis and catabolism may not change this disease, not being the responsible mechanism of hypoalbuminemia. Hypoalbuminemia would appear as compensatory mechanism in view of other protein alterations, as hypergammaglobulinemia, without changes of stabilizing and metabolic properties of albumin, perhaps due to albumin molecular alterations [pt

A product of heme catabolism modulates bacterial function and survival.

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Christopher L Nobles

Full Text Available Bilirubin is the terminal metabolite in heme catabolism in mammals. After deposition into bile, bilirubin is released in large quantities into the mammalian gastrointestinal (GI tract. We hypothesized that intestinal bilirubin may modulate the function of enteric bacteria. To test this hypothesis, we investigated the effect of bilirubin on two enteric pathogens; enterohemorrhagic E. coli (EHEC, a Gram-negative that causes life-threatening intestinal infections, and E. faecalis, a Gram-positive human commensal bacterium known to be an opportunistic pathogen with broad-spectrum antibiotic resistance. We demonstrate that bilirubin can protect EHEC from exogenous and host-generated reactive oxygen species (ROS through the absorption of free radicals. In contrast, E. faecalis was highly susceptible to bilirubin, which causes significant membrane disruption and uncoupling of respiratory metabolism in this bacterium. Interestingly, similar results were observed for other Gram-positive bacteria, including B. cereus and S. aureus. A model is proposed whereby bilirubin places distinct selective pressure on enteric bacteria, with Gram-negative bacteria being protected from ROS (positive outcome and Gram-positive bacteria being susceptible to membrane disruption (negative outcome. This work suggests bilirubin has differential but biologically relevant effects on bacteria and justifies additional efforts to determine the role of this neglected waste catabolite in disease processes, including animal models.

Comparing human-Salmonella with plant-Salmonella protein-protein interaction predictions

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Sylvia eSchleker

2015-01-01

Full Text Available Salmonellosis is the most frequent food-borne disease world-wide and can be transmitted to humans by a variety of routes, especially via animal and plant products. Salmonella bacteria are believed to use not only animal and human but also plant hosts despite their evolutionary distance. This raises the question if Salmonella employs similar mechanisms in infection of these diverse hosts. Given that most of our understanding comes from its interaction with human hosts, we investigate here to what degree knowledge of Salmonella-human interactions can be transferred to the Salmonella-plant system. Reviewed are recent publications on analysis and prediction of Salmonella-host interactomes. Putative protein-protein interactions (PPIs between Salmonella and its human and Arabidopsis hosts were retrieved utilizing purely interolog-based approaches in which predictions were inferred based on available sequence and domain information of known PPIs, and machine learning approaches that integrate a larger set of useful information from different sources. Transfer learning is an especially suitable machine learning technique to predict plant host targets from the knowledge of human host targets. A comparison of the prediction results with transcriptomic data shows a clear overlap between the host proteins predicted to be targeted by PPIs and their gene ontology enrichment in both host species and regulation of gene expression. In particular, the cellular processes Salmonella interferes with in plants and humans are catabolic processes. The details of how these processes are targeted, however, are quite different between the two organisms, as expected based on their evolutionary and habitat differences. Possible implications of this observation on evolution of host-pathogen communication are discussed.

A new technique for measuring protein turnover in the gut, liver and kidneys of lean and obese mice with [3H] glutamic acid

International Nuclear Information System (INIS)

Miller, B.G.; Grimble, R.F.; Taylor, T.G.

1978-01-01

Measurements have been made of the incorporation of an intraperitoneal injection of [ 3 H]glutamate into the protein of the gut, liver and kidney of lean and obese siblings of the genetically obese mouse. Recycling of the 3 H was minimized by using glutamate labelled at the C-2 position. Loss of label from the amino acid pool by transamination and deamination was rapid, with a half-life of 4 h. In tissue protein the amino acid showing the highest 3 H radioactivity was glutamate. The half-lives for protein synthesis and catabolism were calculated from the decay curves of both specific and total radioactivity of [ 3 H] glutamate in tissue protein. No significant differences were found between kidney, liver and gut in lean and obese mice. (author)

[Isolation and characterization of petroleum catabolic broad-host-range plasmids from Shen-Fu wastewater irrigation zone].

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Wang, Ya-Fei; Wang, Ya-Fei; Li, Hui; Li, Xiao-Bin

2013-11-01

Based on triparental mating, we isolated a total of eight broad host range (BHR) petroleum hydrocarbon catabolic plasmids from the soils, sediments, and wastewater samples in the Shen-Fu irrigation zone. The antibiotic resistance of the plasmids was tested, and then, the plasmids were transferred to Escherichia coli EC100. The plasmids carrying no antibiotic resistance were tagged by miniTn5 transposon consisting of antibiotic resistant genes. The PCR-based incompatibility test revealed that the pS3-2C and pS4-6G belonged to Inc P group, the pS3-2G, pW22-3G, and pA15-7G belonged to Inc N group, the pS7-2G was identified as Inc W plasmid, and the pA23-1G and pA10-1C were placed into Inc Q group. By adopting the reported PCR amplification methods of petroleum hydrocarbon-degrading catabolic genes, the petroleum-degrading capability of these BHR plasmids were preliminarily analyzed. The plasmids pS3-2G, pS7-2G, pA23-1G, pW22-3G, and pA10-1C carried aromatic ring- hydroxylating dioxygenase gene phdA and toluene monooxygenase gene touA; the plasmid pA15-7G carried touA and toluene dioxygenase gene tod; the plasmid pS3-2C carried ben, phdA, and tod; whereas the pS4-6G only carried ben. The host range test showed that all the isolated plasmids except pS3-2C could be transferred and maintained stably in the representative strains Agrobacterium tumefaciens C58, Cupriavidus necator JMP228, and E. coli EC100 of the alpha-, beta-, and gamma-Proteobacteria, respectively.

Normal urinary albumin excretion in recently diagnosed type 1 diabetic patients

DEFF Research Database (Denmark)

Lind, B; Jensen, T; Feldt-Rasmussen, B

1989-01-01

of diabetes. Urinary albumin excretion (median and 95% confidence interval) was similar in the diabetic patients and normal control subjects (8 (6-11) vs 8 (6-11) mg 24-h-1, NS). Four diabetic patients had urinary albumin excretion in the microalbuminuric range of 30-300 mg 24-h-1. There was no significant...... difference between the two groups in urinary excretion of retinol binding protein. The distribution among the individuals of both urinary proteins was positively skewed and similar in the two groups. In conclusion, no significant differences in the urinary excretion of albumin and retinol binding protein...... were found between recently diagnosed Type 1 diabetic patients and normal subjects....

Protein and Essential Amino Acids to Protect Musculoskeletal Health during Spaceflight: Evidence of a Paradox?

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Kyle J. Hackney

2014-07-01

Full Text Available Long-duration spaceflight results in muscle atrophy and a loss of bone mineral density. In skeletal muscle tissue, acute exercise and protein (e.g., essential amino acids stimulate anabolic pathways (e.g., muscle protein synthesis both independently and synergistically to maintain neutral or positive net muscle protein balance. Protein intake in space is recommended to be 12%–15% of total energy intake (≤1.4 g∙kg−1∙day−1 and spaceflight is associated with reduced energy intake (~20%, which enhances muscle catabolism. Increasing protein intake to 1.5–2.0 g∙kg−1∙day−1 may be beneficial for skeletal muscle tissue and could be accomplished with essential amino acid supplementation. However, increased consumption of sulfur-containing amino acids is associated with increased bone resorption, which creates a dilemma for musculoskeletal countermeasures, whereby optimizing skeletal muscle parameters via essential amino acid supplementation may worsen bone outcomes. To protect both muscle and bone health, future unloading studies should evaluate increased protein intake via non-sulfur containing essential amino acids or leucine in combination with exercise countermeasures and the concomitant influence of reduced energy intake.

Angiotensin II induced catabolic effect and muscle atrophy are redox dependent

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Semprun-Prieto, Laura C.; Sukhanov, Sergiy; Yoshida, Tadashi; Rezk, Bashir M.; Gonzalez-Villalobos, Romer A.; Vaughn, Charlotte; Tabony, A. Michael; Delafontaine, Patrice

2011-01-01

Angiotensin II (Ang II) causes skeletal muscle wasting via an increase in muscle catabolism. To determine whether the wasting effects of Ang II were related to its ability to increase NADPH oxidase-derived reactive oxygen species (ROS) we infused wild-type C57BL/6J or p47phox−/− mice with vehicle or Ang II for 7 days. Superoxide production was increased 2.4 fold in the skeletal muscle of Ang II infused mice, and this increase was prevented in p47phox−/− mice. Apocynin treatment prevented Ang II-induced superoxide production in skeletal muscle, consistent with Ang II increasing NADPH oxidase derived ROS. Ang II induced loss of body and skeletal muscle weight in C57BL/6J mice, whereas the reduction was significantly attenuated in p47phox−/− animals. The reduction of skeletal muscle weight caused by Ang II was associated with an increase of proteasome activity, and this increase was completely prevented in the skeletal muscle of p47phox−/− mice. In conclusion, Ang II-induced skeletal muscle wasting is in part dependent on NADPH oxidase derived ROS. PMID:21570954

Protein needs in athletes and dietary-nutrition guidelines to gain muscle mass

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Aritz Urdampilleta

2014-05-01

Full Text Available One of the most important effects of strength training is muscular hypertrophy. Athletes should optimize their nutritional management in order to compensate their own genetic limitations. The aim of this review is to analyze the scientific evidence concerning protein intake as a tool to achieve muscle hypertrophy. Depending on the expenditure and energy intake of athlete, a daily protein ranging between 10-15% of total dietary intake is needed. However in sports diets, it is preferable to estimate the amount of protein needed per kilogram of body weight in each individual. In this regard athletes should ingest an amount between 1.2 g and 1.8 g of proteins/kg of body mass/day to maintain their lean mass. In order to increase muscle mass (0.5 kg/week, athletes should take between 1.6 g and 1.8 g of protein/kg/day with an increase of 400-500 kcal in their daily diet. These needs will depend on the sport, muscular catabolic status, the athlete’s lean mass and glycogen stores. Protein needs will increase if muscle and liver glycogen stores are empty. Excess of protein intake (more than 2 g/kg/day, with full glycogen stores, does not benefit the athlete and could cause an increase in circulating ketones and urea, thereby producing an early dehydration.

Sequence of activation of template biosyntheses in normal and transformed human cells after synchronization with a double thimidine block

International Nuclear Information System (INIS)

Alekseev, S.B.; Boikov, P.Ya.; Ebralidze, L.K.; Stepanova, L.G.

1986-01-01

The sequences of synthesis of DNA, RNA, and various groups of proteins in normal and transformed human fibroblasts was studied in the first mitotic cycle synchronization of the cells by a double thymidine block. Two peculiarities of the synthesis of acid-soluble histone and acid-insoluble proteins in the normal and transformed cells, were detected: (1) in normal fibroblasts the synthesis of the two groups of proteins is a minimum before DNA replication, and the greatest activity is achieved in the G 2 phase; in transformed cells protein synthesis is a maximum after the removal of the thymine block, while in the G 2 phase it is decreased; (2) in normal fibroblasts the synthesis of acid-insoluble proteins is a maximum before the maximum synthesis of DNA, and that of acid-soluble proteins is a maximum after the maximum of DNA synthesis. The opposite picture is observed in transformed cells. RNA synthesis in normal and transformed cells is activated at the end of the G 2 phase. In normal cells the synthesis of proteins is coupled with the activation of RNA synthesis, while in transformed cells protein synthesis is evidently transferred to the following mitotic cycle. Especially pronounced differences were detected in the expression of certain LMG proteins. Thus, in transformed cells the regulation of the coupling of the template syntheses is modified

[Behavior of circadian rhythm of ACTH and cortisol in 16 normal subjects after a balanced normocaloric diet and after a high protein diet (Cosinor mean method)].

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Sellini, M; Giovannini, C; Manzo, G; Barletta, C; Borboni, P

1983-01-31

In 16 normal subjects the circadian rhythm of ACTH has been studied during normal calories diet and after a 15 days period of high protein content diet (2 g/Kg body weight). The statistical study, according Cosinor method, has shown a significant increase of the mesor and of the amplitude, but has not shown any change of the ACTH and Cortisol rhythm, after hyperproteic diet. Data advise the increase of the tonic and fasic secretion of both hormones and shown the mantained acrophase. The action of the protein on the ACTH and Cortisol secretion does not seem related to mechanism like stress, neither to the probable mediation of intestinal like-ACTH messengers. On the contrary it seems related to a direct stimulus on the diencephalo-pituitary axis; it is possible that some amino-acids (tryptophan, arginine) act as a mediator, even if data concern just the effect of the over mentioned amino-acid in large doses.

Using megestrol acetate to ameliorate protein-energy wasting in chronic kidney disease.

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Smith, Christine Skouberdis; Logomarsino, John V

2016-03-01

Various populations are affected by chronic kidney disease (CKD), and a low dose appetite stimulant megestrol acetate (MA) is sometimes recommended in patients with CKD to ameliorate protein-energy wasting (PEW). Patients with CKD are at greater risk of developing PEW since the progression of their disease can cause decreased nutrient intake, catabolic effects, systemic inflammation and metabolic changes. Providers can detect PEW in CKD by identifying low serum levels ≤3.8 g/dl of albumin, protein and energy intake increases from 27% to 42%. There are potential adverse effects of using MA in CKD. After reviewing the available literature, the benefits of using MA should be evaluated against the potential side effects. For further examination of MA's potential benefits, long-term, prospective, large clinical trials should be carried out. © 2015 European Dialysis and Transplant Nurses Association/European Renal Care Association.

Cofactor Balance by Nicotinamide Nucleotide Transhydrogenase (NNT) Coordinates Reductive Carboxylation and Glucose Catabolism in the Tricarboxylic Acid (TCA) Cycle*♦

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Gameiro, Paulo A.; Laviolette, Laura A.; Kelleher, Joanne K.; Iliopoulos, Othon; Stephanopoulos, Gregory

2013-01-01

Cancer and proliferating cells exhibit an increased demand for glutamine-derived carbons to support anabolic processes. In addition, reductive carboxylation of α-ketoglutarate by isocitrate dehydrogenase 1 (IDH1) and 2 (IDH2) was recently shown to be a major source of citrate synthesis from glutamine. The role of NAD(P)H/NAD(P)+ cofactors in coordinating glucose and glutamine utilization in the tricarboxylic acid (TCA) cycle is not well understood, with the source(s) of NADPH for the reductive carboxylation reaction remaining unexplored. Nicotinamide nucleotide transhydrogenase (NNT) is a mitochondrial enzyme that transfers reducing equivalents from NADH to NADPH. Here, we show that knockdown of NNT inhibits the contribution of glutamine to the TCA cycle and activates glucose catabolism in SkMel5 melanoma cells. The increase in glucose oxidation partially occurred through pyruvate carboxylase and rendered NNT knockdown cells more sensitive to glucose deprivation. Importantly, knocking down NNT inhibits reductive carboxylation in SkMel5 and 786-O renal carcinoma cells. Overexpression of NNT is sufficient to stimulate glutamine oxidation and reductive carboxylation, whereas it inhibits glucose catabolism in the TCA cycle. These observations are supported by an impairment of the NAD(P)H/NAD(P)+ ratios. Our findings underscore the role of NNT in regulating central carbon metabolism via redox balance, calling for other mechanisms that coordinate substrate preference to maintain a functional TCA cycle. PMID:23504317

Low-Normal FMR1 CGG Repeat Length: Phenotypic Associations

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Marsha eMailick

2014-09-01

Full Text Available This population-based study investigates genotype-phenotype correlations of low-normal CGG repeats in the fragile X mental retardation 1 (FMR1 gene. FMR1 plays an important role in brain development and function, and encodes FMRP (fragile X mental retardation protein, an RNA-binding protein that regulates protein synthesis impacting activity-dependent synaptic development and plasticity. Most past research has focused on CGG premutation expansions (41 to 200 CGG repeats and on fragile X syndrome (200+ CGG repeats, with considerably less attention on the other end of the spectrum of CGG repeats. Using existing data, older adults with 23 or fewer CGG repeats (2 SDs below the mean were compared with age-peers who have normal numbers of CGGs (24-40 with respect to cognition, mental health, cancer, and having children with disabilities. Men (n = 341 with an allele in the low-normal range and women (n = 46 with two low-normal alleles had significantly more difficulty with their memory and ability to solve day to day problems. Women with both FMR1 alleles in the low-normal category had significantly elevated odds of feeling that they need to drink more to get the same effect as in the past. These women also had two and one-half times the odds of having had breast cancer and four times the odds of uterine cancer. Men and women with low-normal CGGs had higher odds of having a child with a disability, either a developmental disability or a mental health condition. These findings are in line with the hypothesis that there is a need for tight neuronal homeostatic control mechanisms for optimal cognitive and behavioral functioning, and more generally that low numbers as well as high numbers of CGG repeats may be problematic for health.

Comparative proteomics of matrix fractions between pimpled and normal chicken eggshells.

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Liu, Zhangguo; Song, Lingzi; Lu, Lizhi; Zhang, Xianfu; Zhang, Fuming; Wang, Kehua; Linhardt, Robert J

2017-09-07

Eggshell matrix can be dissociated into three matrix fractions: acid-insoluble matrix (M1), water-insoluble matrix (M2) and acid-water facultative-soluble matrix (M3). Matrix fractions from pimpled and normal eggshells were compared using label-free proteomic method to understand the differences among three matrix fractions and the proteins involved with eggshell quality. A total of 738 and 600 proteins were identified in the pimpled and normal calcified eggshells, respectively. Both eggshells showed a combined proteomic inventory of 769 proteins. In the same type of eggshell, a high similarity was present in the proteomes of three matrix fractions. These triply overlapped common proteins formed the predominant contributor to proteomic abundance in the matrix fractions. In each matrix fraction and between both eggshell models, normal and pimpled eggshells, a majority of the proteomes of the fractions were commonly observed. Forty-two common major proteins (iBAQ-derived abundance ≥0.095% of proteomic abundance) were identified throughout the three matrix fractions and these proteins might act as backbone constituents in chicken eggshell matrix. Finally, using 1.75-fold as up-regulated and using 0.57-fold as down-regulated cutoff values, twenty-five differential major proteins were screened and they all negatively influence and none showed any effect on eggshell quality. Overall, we uncovered the characteristics of proteomics of three eggshell matrix fractions and identified candidate proteins influencing eggshell quality. The next research on differential proteins will uncover the potential mechanisms underlying how proteins affect eggshell quality. It was reported that the proteins in an eggshell can be divided into insoluble and soluble proteins. The insoluble proteins are thought to be an inter-mineral matrix and acts as a structural framework, while the soluble proteins are thought as intra-mineral matrix that are embedded within the crystal during

Amino acid starvation has opposite effects on mitochondrial and cytosolic protein synthesis.

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Mark A Johnson

Full Text Available Amino acids are essential for cell growth and proliferation for they can serve as precursors of protein synthesis, be remodelled for nucleotide and fat biosynthesis, or be burnt as fuel. Mitochondria are energy producing organelles that additionally play a central role in amino acid homeostasis. One might expect mitochondrial metabolism to be geared towards the production and preservation of amino acids when cells are deprived of an exogenous supply. On the contrary, we find that human cells respond to amino acid starvation by upregulating the amino acid-consuming processes of respiration, protein synthesis, and amino acid catabolism in the mitochondria. The increased utilization of these nutrients in the organelle is not driven primarily by energy demand, as it occurs when glucose is plentiful. Instead it is proposed that the changes in the mitochondrial metabolism complement the repression of cytosolic protein synthesis to restrict cell growth and proliferation when amino acids are limiting. Therefore, stimulating mitochondrial function might offer a means of inhibiting nutrient-demanding anabolism that drives cellular proliferation.

Alternative pathways of dehydroascorbic acid degradation in vitro and in plant cell cultures: novel insights into vitamin C catabolism.

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Parsons, Harriet T; Yasmin, Tayyaba; Fry, Stephen C

2011-12-15

L-Ascorbate catabolism involves reversible oxidation to DHA (dehydroascorbic acid), then irreversible oxidation or hydrolysis. The precursor-product relationships and the identity of several major DHA breakdown products remained unclear. In the presence of added H2O2, DHA underwent little hydrolysis to DKG (2,3-dioxo-L-gulonate). Instead, it yielded OxT (oxalyl L-threonate), cOxT (cyclic oxalyl L-threonate) and free oxalate (~6:1:1), essentially simultaneously, suggesting that all three product classes independently arose from one reactive intermediate, proposed to be cyclic-2,3-O-oxalyl-L-threonolactone. Only with plant apoplastic esterases present were the esters significant precursors of free oxalate. Without added H2O2, DHA was slowly hydrolysed to DKG. Downstream of DKG was a singly ionized dicarboxy compound (suggested to be 2-carboxy-L-xylonolactone plus 2-carboxy-L-lyxonolactone), which reversibly de-lactonized to a dianionic carboxypentonate. Formation of these lactones and acid was minimized by the presence of residual unreacted ascorbate. In vivo, the putative 2-carboxy-L-pentonolactones were relatively stable. We propose that DHA is a branch-point in ascorbate catabolism, being either oxidized to oxalate and its esters or hydrolysed to DKG and downstream carboxypentonates. The oxidation/hydrolysis ratio is governed by reactive oxygen species status. In vivo, oxalyl esters are enzymatically hydrolysed, but the carboxypentonates are stable. The biological roles of these ascorbate metabolites invite future exploration.

Autophagy Proteins in Phagocyte Endocytosis and Exocytosis

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Christian Münz

2017-09-01

Full Text Available Autophagy was initially described as a catabolic pathway that recycles nutrients of cytoplasmic constituents after lysosomal degradation during starvation. Since the immune system monitors products of lysosomal degradation via major histocompatibility complex (MHC class II restricted antigen presentation, autophagy was found to process intracellular antigens for display on MHC class II molecules. In recent years, however, it has become apparent that the molecular machinery of autophagy serves phagocytes in many more membrane trafficking pathways, thereby regulating immunity to infectious disease agents. In this minireview, we will summarize the recent evidence that autophagy proteins regulate phagocyte endocytosis and exocytosis for myeloid cell activation, pathogen replication, and MHC class I and II restricted antigen presentation. Selective stimulation and inhibition of the respective functional modules of the autophagy machinery might constitute valid therapeutic options in the discussed disease settings.

Mechanism of internal browning of pineapple: The role of gibberellins catabolism gene (AcGA2ox) and GAs

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Zhang, Qin; Rao, Xiuwen; Zhang, Lubin; He, Congcong; Yang, Fang; Zhu, Shijiang

2016-01-01

Internal browning (IB), a physiological disorder (PD) that causes severe losses in harvested pineapple, can be induced by exogenous gibberellins (GAs). Over the years, studies have focused on roles of Gibberellin 2-oxidase (GA2oxs), the major GAs catabolic enzyme in plants, in the regulation of changes in morphology or biomass. However, whether GA2oxs could regulate PD has not been reported. Here, a full-length AcGA2ox cDNA was isolated from pineapple, with the putative protein sharing 23.59% to 72.92% identity with GA2oxs from five other plants. Pineapples stored at 5 °C stayed intact, while those stored at 20 °C showed severe IB. Storage at 5 °C enhanced AcGA2ox expression and decreased levels of a GAs (GA4) ‘compared with storage at 20 °C. However, at 20 °C, exogenous application of abscisic acid (ABA) significantly suppressed IB. ABA simultaneously upregulated AcGA2ox and reduced GA4. Ectopic expression of AcGA2ox in Arabidopsis resulted in reduced GA4, lower seed germination, and shorter hypocotyls and roots, all of which were restored by exogenous GA4/7. Moreover, in pineapple, GA4/7 upregulated polyphenol oxidase, while storage at 5 °C and ABA downregulated it. These results strongly suggest the involvement of AcGA2ox in regulation of GAs levels and a role of AcGA2ox in regulating IB. PMID:27982026

Etiology of the protein-energy wasting syndrome in chronic kidney disease: a consensus statement from the International Society of Renal Nutrition and Metabolism (ISRNM).

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Carrero, Juan Jesús; Stenvinkel, Peter; Cuppari, Lilian; Ikizler, T Alp; Kalantar-Zadeh, Kamyar; Kaysen, George; Mitch, William E; Price, S Russ; Wanner, Christoph; Wang, Angela Y M; ter Wee, Pieter; Franch, Harold A

2013-03-01

Protein-energy wasting (PEW), a term proposed by the International Society of Renal Nutrition and Metabolism (ISRNM), refers to the multiple nutritional and catabolic alterations that occur in chronic kidney disease (CKD) and associate with morbidity and mortality. To increase awareness, identify research needs, and provide the basis for future work to understand therapies and consequences of PEW, ISRNM provides this consensus statement of current knowledge on the etiology of PEW syndrome in CKD. Although insufficient food intake (true undernutrition) due to poor appetite and dietary restrictions contribute, other highly prevalent factors are required for the full syndrome to develop. These include uremia-induced alterations such as increased energy expenditure, persistent inflammation, acidosis, and multiple endocrine disorders that render a state of hypermetabolism leading to excess catabolism of muscle and fat. In addition, comorbid conditions associated with CKD, poor physical activity, frailty, and the dialysis procedure per se further contribute to PEW. Published by Elsevier Inc.

Evaluation of Normalization Methods on GeLC-MS/MS Label-Free Spectral Counting Data to Correct for Variation during Proteomic Workflows

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Gokce, Emine; Shuford, Christopher M.; Franck, William L.; Dean, Ralph A.; Muddiman, David C.

2011-12-01

Normalization of spectral counts (SpCs) in label-free shotgun proteomic approaches is important to achieve reliable relative quantification. Three different SpC normalization methods, total spectral count (TSpC) normalization, normalized spectral abundance factor (NSAF) normalization, and normalization to selected proteins (NSP) were evaluated based on their ability to correct for day-to-day variation between gel-based sample preparation and chromatographic performance. Three spectral counting data sets obtained from the same biological conidia sample of the rice blast fungus Magnaporthe oryzae were analyzed by 1D gel and liquid chromatography-tandem mass spectrometry (GeLC-MS/MS). Equine myoglobin and chicken ovalbumin were spiked into the protein extracts prior to 1D-SDS- PAGE as internal protein standards for NSP. The correlation between SpCs of the same proteins across the different data sets was investigated. We report that TSpC normalization and NSAF normalization yielded almost ideal slopes of unity for normalized SpC versus average normalized SpC plots, while NSP did not afford effective corrections of the unnormalized data. Furthermore, when utilizing TSpC normalization prior to relative protein quantification, t-testing and fold-change revealed the cutoff limits for determining real biological change to be a function of the absolute number of SpCs. For instance, we observed the variance decreased as the number of SpCs increased, which resulted in a higher propensity for detecting statistically significant, yet artificial, change for highly abundant proteins. Thus, we suggest applying higher confidence level and lower fold-change cutoffs for proteins with higher SpCs, rather than using a single criterion for the entire data set. By choosing appropriate cutoff values to maintain a constant false positive rate across different protein levels (i.e., SpC levels), it is expected this will reduce the overall false negative rate, particularly for proteins with

Effects of protein deficiency on the rate of radioactivity loss from body constituents in adult rats given 14C-amino acids

International Nuclear Information System (INIS)

Yamamoto, Shigeru; Inoue, Goro

1975-01-01

The effect of protein deficiency on the rate of loss of radioactivity from body constituents was studied in adult rats administered 14 C-Chlorella protein hydrolysate or 14 C-lysine. Rats were kept on a protein-free diet for 3 weeks and then injected with labelled amino acids and fed on a protein-free diet for 3 more days to allow 14 C deposition in tissues. Then they were given experimental diets (protein-free diet, 1% and 10% wheat gluten diets pair-fed with the protein-free diet, and 10% wheat gluten diet ad libitum) for 7 days and sacrificed. The rates of loss of radioactivity from tissue proteins became low in general with the extent of protein deficiency. This increased capacity of tissues to retain 14 C-amino acids may result from higher efficiency of protein utilization in protein deficiency. The reutilization of free amino acids and the rate of catabolism of tissue protein are discussed on the basis of the results. The half-life of muscle protein was too long to observe the effects of experimental diets given for 7 days on the rate of loss of radioactivity. (auth.)

Engineering Bacteria to Catabolize the Carbonaceous Component of Sarin: Teaching E. coli to Eat Isopropanol

DEFF Research Database (Denmark)

Brown, Margaret E.; Mukhopadhyay, Aindrila; Keasling, Jay D.

2016-01-01

conversion with a key reaction performed by the acetone carboxylase complex (ACX). We engineered the heterologous expression of the ACX complex from Xanthobacter autotrophicus PY2 to match the naturally occurring subunit stoichiometry and purified the recombinant complex from E. coli for biochemical analysis....... Incorporating this ACX complex and enzymes from diverse organisms, we introduced an isopropanol degradation pathway in E. coli, optimized induction conditions, and decoupled enzyme expression to probe pathway bottlenecks. Our engineered E. coli consumed 65% of isopropanol compared to no-cell controls......We report an engineered strain of Escherichia coli that catabolizes the carbonaceous component of the extremely toxic chemical warfare agent sarin. Enzymatic decomposition of sarin generates isopropanol waste that, with this engineered strain, is then transformed into acetyl-CoA by enzymatic...

Olfactory marker protein: turnover and transport in normal and regenerating neurons

International Nuclear Information System (INIS)

Kream, R.M.; Margolis, F.L.

1984-01-01

A 19,000-dalton acidic protein designated olfactory marker protein (OMP) is a cell-specific marker of mature olfactory chemosensory neurons. Intranasal irrigation of mouse olfactory epithelium with [ 35 S]methionine labeled OMP to high specific activity. Turnover and transport characteristics of 35 S-labeled OMP were compared to those of 35 S-labeled global cytosol protein in groups of young, adult, and Triton-treated adult mice. The latter contained primarily large numbers of regenerating olfactory neurons. In olfactory epithelium of young and Triton-treated mice, the specific activity of OMP was three times that of global cytosol protein, whereas in adults the two measures were equal. In all three groups, however, the rate of degradation of OMP was roughly equal to that of cytosol protein (T1/2 . 5 to 6 days). By contrast, differences in T1/2 for OMP decline in the bulb of adult, young, and Triton-treated adult mice were highly significant (T1/2's of 9.3, 6.1, and 4 to 5 days, respectively; p . 0.001). The specific activity of [35S]methionine incorporated in OMP exceeded that of the free amino acid 5-fold, indicating minimal precursor reutilization during the course of our experiments. Turnover data indicate that increased isotope incorporation into OMP in the epithelium is matched by an accelerated rate of degradation in the bulb. This may be correlated with the physiological state or developmental age of the primary neurons since in young and Triton-treated adult mice, rapidly maturing ''young'' olfactory neurons represent a larger proportion of the total population than in adults. Thus, OMP behaves as a typical, relatively slowly transported soluble protein (v . 2 to 4 mm/day, slow component b)

Glucose and protein kinetics in patients undergoing colorectal surgery: perioperative amino acid versus hypocaloric dextrose infusion.

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Lugli, Andrea Kopp; Schricker, Thomas; Wykes, Linda; Lattermann, Ralph; Carli, Franco

2010-11-01

Surgical injury provokes a stress response that leads to a catabolic state and, when prolonged, interferes with the postoperative recovery process. This study tests the impact of 2 nutrition support regimens on protein and glucose metabolism as part of an integrated approach in the perioperative period incorporating epidural analgesia in 18 nondiabetic patients undergoing colorectal surgery. To test the hypothesis that parenteral amino acid infusion (amino acid group, n = 9) maintains glucose homeostasis while maintaining normoglycemia and reduces proteolysis compared with infusion of dextrose alone (DEX group, n = 9), glucose and protein kinetics were measured before and on the second day after surgery using a stable isotope tracer technique. Postoperatively, the rate of appearance of glucose was higher (P dextrose alone. Copyright © 2010 Elsevier Inc. All rights reserved.

Getting to the meat of the matter: beyond protein supplementation in maintenance dialysis.

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Bailey, James L; Franch, Harold A

2009-01-01

Until recently, patients on dialysis with low serum albumin levels were characterized as suffering from protein malnutrition suggesting that the cause of this malady was due to an inadequate intake of protein. In fact, these patients tend to suffer from a wasting syndrome similar to cachexia commonly associated with inflammation in which there is loss of lean body mass and fat mass is underutilized. The term protein energy wasting has been used to characterize this syndrome and suggests that the simple addition of protein supplements to the dietary regimen of hemodialysis patients will not cure this malady. Correction of the underlying inflammatory disorder which drives losses of body protein and fuel reserves is far more important and is the single most effective therapy. Protein supplements which may promote albumin synthesis and synthesis of liver-related proteins tend to increase muscle catabolism. Muscle growth is not fostered by increasing dietary protein above recommended goals for dialysis patients, but can be promoted by the addition of protein of high biological value that is rich in leucine and other essential amino acids in tandem with repetitive exercises. Ultimately, correction of PEW hinges on the diagnosis and treatment of co-morbid conditions in combination with strategies to replenish caloric and protein stores. A supplementary exercise program would allow recovery of lean body mass. Given the multiple co-morbidities that exist in this population, therapy would have to be individualized.

Polycomb group protein-mediated repression of transcription

DEFF Research Database (Denmark)

Morey, Lluís; Helin, Kristian

2010-01-01

The polycomb group (PcG) proteins are essential for the normal development of multicellular organisms. They form multi-protein complexes that work as transcriptional repressors of several thousand genes controlling differentiation pathways during development. How the PcG proteins work as transcri......The polycomb group (PcG) proteins are essential for the normal development of multicellular organisms. They form multi-protein complexes that work as transcriptional repressors of several thousand genes controlling differentiation pathways during development. How the PcG proteins work...... as transcriptional repressors is incompletely understood, but involves post-translational modifications of histones by two major PcG protein complexes: polycomb repressive complex 1 and polycomb repressive complex 2....

Regulation of the autophagy protein LC3 by phosphorylation

Science.gov (United States)

Cherra, Salvatore J.; Kulich, Scott M.; Uechi, Guy; Balasubramani, Manimalha; Mountzouris, John; Day, Billy W.

2010-01-01

Macroautophagy is a major catabolic pathway that impacts cell survival, differentiation, tumorigenesis, and neurodegeneration. Although bulk degradation sustains carbon sources during starvation, autophagy contributes to shrinkage of differentiated neuronal processes. Identification of autophagy-related genes has spurred rapid advances in understanding the recruitment of microtubule-associated protein 1 light chain 3 (LC3) in autophagy induction, although braking mechanisms remain less understood. Using mass spectrometry, we identified a direct protein kinase A (PKA) phosphorylation site on LC3 that regulates its participation in autophagy. Both metabolic (rapamycin) and pathological (MPP+) inducers of autophagy caused dephosphorylation of endogenous LC3. The pseudophosphorylated LC3 mutant showed reduced recruitment to autophagosomes, whereas the nonphosphorylatable mutant exhibited enhanced puncta formation. Finally, autophagy-dependent neurite shortening induced by expression of a Parkinson disease–associated G2019S mutation in leucine-rich repeat kinase 2 was inhibited by dibutyryl–cyclic adenosine monophosphate, cytoplasmic expression of the PKA catalytic subunit, or the LC3 phosphorylation mimic. These data demonstrate a role for phosphorylation in regulating LC3 activity. PMID:20713600

Inhibition of skeletal muscle protein synthesis in septic intra-abdominal abscess

International Nuclear Information System (INIS)

Vary, T.C.; Siegel, J.H.; Tall, B.D.; Morris, J.G.; Smith, J.A.

1988-01-01

Chronic sepsis is always associated with profound wasting leading to increased release of amino acids from skeletal muscle. Net protein catabolism may be due to decreased rate of synthesis, increased rate of degradation, or both. To determine whether protein synthesis is altered in chronic sepsis, the rate of protein synthesis in vivo was estimated by measuring the incorporation of [ 3 H]-phenylalanine in skeletal muscle protein in a chronic (5-day) septic rat model induced by creation of a stable intra-abdominal abscess using an E. coli + B. fragilis-infected sterile fecal-agar pellet as foreign body nidus. Septic rats failed to gain weight at rates similar to control animals, therefore control animals were weight matched to the septic animals. The skeletal muscle protein content in septic animals was significantly reduced relative to control animals (0.18 +/- 0.01 vs. 0.21 +/- 0.01 mg protein/gm wet wt; p less than 0.02). The rate of incorporation of [ 3 H]-phenylalanine into skeletal muscle protein from control animals was 39 +/- 4 nmole/gm wet wt/hr or a fractional synthetic rate of 5.2 +/- 0.5%/day. In contrast to control animals, the fractional synthetic rate in septic animals (2.6 +/- 0.2%/day) was reduced by 50% compared to control animals (p less than 0.005). The decreased rate of protein synthesis in sepsis was not due to an energy deficit, as high-energy phosphates and ATP/ADP ratio were not altered. This decrease in protein synthesis occurred even though septic animals consumed as much food as control animals

Skeletal muscle neuronal nitric oxide synthase micro protein is reduced in people with impaired glucose homeostasis and is not normalized by exercise training.

Science.gov (United States)

Bradley, Scott J; Kingwell, Bronwyn A; Canny, Benedict J; McConell, Glenn K

2007-10-01

Skeletal muscle inducible nitric oxide synthase (NOS) protein is greatly elevated in people with type 2 diabetes mellitus, whereas endothelial NOS is at normal levels. Diabetic rat studies suggest that skeletal muscle neuronal NOS (nNOS) micro protein expression may be reduced in human insulin resistance. The aim of this study was to determine whether skeletal muscle nNOSmicro protein expression is reduced in people with impaired glucose homeostasis and whether exercise training increases nNOSmicro protein expression in these individuals because exercise training increases skeletal muscle nNOSmicro protein in rats. Seven people with type 2 diabetes mellitus or prediabetes (impaired fasting glucose and/or impaired glucose tolerance) and 7 matched (sex, age, fitness, body mass index, blood pressure, lipid profile) healthy controls aged 36 to 60 years participated in this study. Vastus lateralis muscle biopsies for nNOSmicro protein determination were obtained, aerobic fitness was measured (peak pulmonary oxygen uptake [Vo(2) peak]), and glucose tolerance and insulin homeostasis were assessed before and after 1 and 4 weeks of cycling exercise training (60% Vo(2) peak, 50 minutes x 5 d wk(-1)). Skeletal muscle nNOSmicro protein was significantly lower (by 32%) in subjects with type 2 diabetes mellitus or prediabetes compared with that in controls before training (17.7 +/- 1.2 vs 26.2 +/- 3.4 arbitrary units, P glucose homeostasis have reduced skeletal muscle nNOSmicro protein content. However, because exercise training improves insulin sensitivity without influencing skeletal muscle nNOSmicro protein expression, it seems that changes in skeletal muscle nNOSmicro protein are not central to the control of insulin sensitivity in humans and therefore may be a consequence rather than a cause of diabetes.

Neural responses to visual food stimuli after a normal vs. higher protein breakfast in breakfast-skipping teens: a pilot fMRI study.