Methylobacterium suomiense sp. nov. and Methylobacterium lusitanum sp. nov., aerobic, pink-pigmented, facultatively methylotrophic bacteria.

Science.gov (United States)

Doronina, Nina V; Trotsenko, Yuri A; Kuznetsov, Boris B; Tourova, Tatjana P; Salkinoja-Salonen, Mirja S

2002-05-01

Two aerobic, pink-pigmented, facultatively methylotrophic bacteria, strains F20T and RXM(T), are described taxonomically. On the basis of their phenotypic and genotypic properties, the isolates are proposed as novel species of the genus Methylobacterium, Methylobacterium suomiense sp. nov. (type strain F20T = VKM B-2238T = NCIMB 13778T) and Methylobacterium lusitanum sp. nov. (type strain RXMT = VKM B-2239T = NCIMB 13779T).

Evolution, Metabolism and Biotechnological Usage of Methylotrophic Microorganisms

OpenAIRE

Oleg Mosin; Ignat Ignatov

2014-01-01

Methylotrophs – aerobic chemoheterotrophic microorganisms submitted by cocci and bacilli mobile forms, are inhabitants of reservoirs and soils of various type, where there are going on various processes of decomposition of organic substances with formation of the one-carbon С1-compounds and some С2-, and С3-compounds, capable to be assimilated by methylotrophs. These microorganisms assimilating carbon on ribuloso-5-monophospate and serine pathways, are allocated from soil ground, the sewage c...

A new compound of thiophenylated pyridazinone IMB5043 showing potent antitumor efficacy through ATM-Chk2 pathway.

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Jianhua Gong

Full Text Available Through cell-based screening models, we have identified a new compound IMB5043, a thiophenylated pyridazinone, which exerted cytotoxicity against cancer cells. In the present study, we evaluated its antitumor efficacy and the possible mechanism. By MTT assay, IMB5043 inhibited the proliferation of various human cancer cells lines, especially hepatocarcinoma SMMC-7721 cells. IMB5043 blocked cell cycle with G2/M arrest, induced cell apoptosis, and inhibited the migration and invasion of SMMC-7721 cells. As verified by comet assay and γ-H2AX foci formation, IMB5043 caused DNA damage and activated ATM, Chk2 and p53 through phosphorylation. As shown by Gene microarray analysis, the differentially expressed genes in SMMC-7721 cells treated with IMB5043 were highly related to cell death and apoptosis. IMB5043 suppressed the growth of hepatocarcinoma SMMC-7721 xenograft in athymic mice. By histopathological examination, no lesions were found in bone marrow and various organs of the treated mice. Our findings reveal that IMB5043 as an active compound consisting of both pyridazinone and thiophene moieties exerts antitumor efficacy through activation of ATM-Chk2 pathway. IMB5043 may serve as a promising leading compound for the development of antitumor drugs.

Performance Evaluation of Supercomputers using HPCC and IMB Benchmarks

Science.gov (United States)

Saini, Subhash; Ciotti, Robert; Gunney, Brian T. N.; Spelce, Thomas E.; Koniges, Alice; Dossa, Don; Adamidis, Panagiotis; Rabenseifner, Rolf; Tiyyagura, Sunil R.; Mueller, Matthias;

Taxonomy of oxalotrophic Methylobacterium strains

Science.gov (United States)

Sahin, Nurettin; Kato, Yuko; Yilmaz, Ferah

2008-10-01

Most of the oxalotrophic bacteria are facultative methylotrophs and play important ecological roles in soil fertility and cycling of elements. This study gives a detailed picture of the taxonomy and diversity of these bacteria and provides new information about the taxonomical variability within the genus Methylobacterium. Twelve mesophilic, pink-pigmented, and facultatively methylotrophic oxalate-oxidizing strains were included in this work that had been previously isolated from the soil and some plant tissues by the potassium oxalate enrichment method. The isolates were characterized using biochemical tests, cellular lipid profiles, spectral characteristics of carotenoid pigments, G+C content of the DNA, and 16S rDNA sequencing. The taxonomic similarities among the strains were analyzed using the simple matching ( S SM) and Jaccard ( S J) coefficients, and the UPGMA clustering algorithm. The phylogenetic position of the strains was inferred by the neighbor-joining method on the basis of the 16S rDNA sequences. All isolates were Gram-negative, facultatively methylotrophic, oxidase and catalase positive, and required no growth factors. Based on the results of numerical taxonomy, the strains formed four closely related clusters sharing ≥85% similarity. Analysis of the 16S rDNA sequences demonstrated that oxalotrophic, pink-pigmented, and facultatively methylotrophic strains could be identified as members of the genus Methylobacterium. Except for M. variabile and M. aquaticum, all of the Methylobacterium type strains tested had the ability of oxalate utilization. Our results indicate that the capability of oxalate utilization seems to be an uncommon trait and could be used as a valuable taxonomic criterion for differentiation of Methylobacterium species.

Analysis of Active Methylotrophic Communities: When DNA-SIP Meets High-Throughput Technologies.

Science.gov (United States)

Taubert, Martin; Grob, Carolina; Howat, Alexandra M; Burns, Oliver J; Chen, Yin; Neufeld, Josh D; Murrell, J Colin

2016-01-01

Methylotrophs are microorganisms ubiquitous in the environment that can metabolize one-carbon (C1) compounds as carbon and/or energy sources. The activity of these prokaryotes impacts biogeochemical cycles within their respective habitats and can determine whether these habitats act as sources or sinks of C1 compounds. Due to the high importance of C1 compounds, not only in biogeochemical cycles, but also for climatic processes, it is vital to understand the contributions of these microorganisms to carbon cycling in different environments. One of the most challenging questions when investigating methylotrophs, but also in environmental microbiology in general, is which species contribute to the environmental processes of interest, or "who does what, where and when?" Metabolic labeling with C1 compounds substituted with (13)C, a technique called stable isotope probing, is a key method to trace carbon fluxes within methylotrophic communities. The incorporation of (13)C into the biomass of active methylotrophs leads to an increase in the molecular mass of their biomolecules. For DNA-based stable isotope probing (DNA-SIP), labeled and unlabeled DNA is separated by isopycnic ultracentrifugation. The ability to specifically analyze DNA of active methylotrophs from a complex background community by high-throughput sequencing techniques, i.e. targeted metagenomics, is the hallmark strength of DNA-SIP for elucidating ecosystem functioning, and a protocol is detailed in this chapter.

Validation of an Information-Motivation-Behavioral Skills model of diabetes self-care (IMB-DSC).

Science.gov (United States)

Osborn, Chandra Y; Egede, Leonard E

2010-04-01

Comprehensive behavior change frameworks are needed to provide guidance for the design, implementation, and evaluation of diabetes self-care programs in diverse populations. We applied the Information-Motivation-Behavioral Skills (IMB) model, a well-validated, comprehensive health behavior change framework, to diabetes self-care. Patients with diabetes were recruited from an outpatient clinic. Information gathered pertained to demographics, diabetes knowledge (information); diabetes fatalism (personal motivation); social support (social motivation); and diabetes self-care (behavior). Hemoglobin A1C values were extracted from the patient medical record. Structural equation models tested the IMB framework. More diabetes knowledge (r=0.22 pbehavior; and through behavior, were related to glycemic control (r=-0.20, pmotivation (less fatalistic attitudes), and social motivation (more social support) was associated with behavior; and behavior was the sole predictor of glycemic control. The IMB model is an appropriate, comprehensive health behavior change framework for diabetes self-care. The findings indicate that in addition to knowledge, diabetes education programs should target personal and social motivation to effect behavior change. 2009 Elsevier Ireland Ltd. All rights reserved.

Discovery of rare protein-coding genes in model methylotroph Methylobacterium extorquens AM1.

Science.gov (United States)

Kumar, Dhirendra; Mondal, Anupam Kumar; Yadav, Amit Kumar; Dash, Debasis

2014-12-01

Proteogenomics involves the use of MS to refine annotation of protein-coding genes and discover genes in a genome. We carried out comprehensive proteogenomic analysis of Methylobacterium extorquens AM1 (ME-AM1) from publicly available proteomics data with a motive to improve annotation for methylotrophs; organisms capable of surviving in reduced carbon compounds such as methanol. Besides identifying 2482(50%) proteins, 29 new genes were discovered and 66 annotated gene models were revised in ME-AM1 genome. One such novel gene is identified with 75 peptides, lacks homolog in other methylobacteria but has glycosyl transferase and lipopolysaccharide biosynthesis protein domains, indicating its potential role in outer membrane synthesis. Many novel genes are present only in ME-AM1 among methylobacteria. Distant homologs of these genes in unrelated taxonomic classes and low GC-content of few genes suggest lateral gene transfer as a potential mode of their origin. Annotations of methylotrophy related genes were also improved by the discovery of a short gene in methylotrophy gene island and redefining a gene important for pyrroquinoline quinone synthesis, essential for methylotrophy. The combined use of proteogenomics and rigorous bioinformatics analysis greatly enhanced the annotation of protein-coding genes in model methylotroph ME-AM1 genome. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The Evaluation Study of the Determination of the Sub-District IMB Retribution Revenue in Bandung District

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Fernandes Simangunsong

2016-06-01

Full Text Available The aim of this study is for knowing  the realization of IMB levy achieved by all districts in Bandung regency and their potency. This study implemented qualitative and quantitative approach with triangulation technic. After analizing the data, there are some findings. First, there are only five districts that can achieve the target of 100%. They are Pasir jambu, Cicalengka, Soreang, Kutawaringin and Cimenyan. Next, the average realization of IMB levy in Bandung regency is Rp  Rp. 820.034.365,00 or 72,53% of total target. It is is still far from the target due to some factors. They are limited human resources,  low monitoring, low society’s participation in having IMB and low motivation from implementers for carrying out the policy. Further, based on high , moderat, and low approach, the potency of receiving IMB levy is good enough. If the assumption of  IMB levy is 5%, the estimation of levy target is 47.849.901.114 with high approach, Rp 41.969.646.924 with high moderate and, Rp 36.099.392.733. with low approach. 

The IMB proton decay detector

International Nuclear Information System (INIS)

Svoboda, R.C.; Gajewski, W.; Kropp, W.R.; Reines, F.; Schultz, J.; Smith, D.W.; Sobel, H.; Wuest, C.; Bionta, R.M.; Cortez, B.G.; Errede, S.; Foster, G.W.; Greenberg, J.; Park, H.S.; Shumard, E.; Sinclair, D.; Stone, J.L.; Sulak, L.R.; Velde, J.C. van der; Goldhaber, M.; Blewitt, G.; Lehmann, E.; LoSecco, J.M.; Bratton, C.B.; Learned, J.; Svoboda, R.; Jones, T.W.; Ramana Murthy, P.V.

1983-01-01

A description is given of the Irvine-Michigan-Brookhaven proton decay detector which is nearing completion in a salt mine in Cleveland, Ohio, U.S.A. The detector is a water Cerenkov one with a fiducial volume of 4,000 tons and a threshold of 24 MeV. Initial results indicate that the detector is working according to specification and has a high potential for deep underground cosmic ray applications. I will give a brief account of the IMB detector construction and operation and also its present status and possible cosmic ray applications. (orig.)

Isolation of L-methionine-enriched mutant of a methylotrophic yeast, Candida boidinii No.2201

International Nuclear Information System (INIS)

Tani, Y.; Lim, W.J.; Yang, H.C.

1988-01-01

Six strains of methylotrophic yeast were examined for production of L-methionine-enriched cells. Candida boidinii (kloeckera sp.) No. 2201,which accumulated 0.54 mg/g-dry cell weight (DCW) of free L-methionine (pool methionine), was selected as the parental strain for breeding L-methionine-rich mutants. Ethionine-resistant mutants were derived from the strain by UV irradiation. A mutant strain, E500-78,which was resistant to 500 μg/ml of DL-ethionine, accumulated 6.02 mg/g-DCW of pool methionine. The culture conditions for mutant strain E500-78 to increase pool methionine accumulation were optimized. As a result, the mutant strain accumulated 8.80 mg/g-DCW of pool methionine and contained 16.02 mg/g-DCW total methionine

[Isolation and preliminary characterization of carotenoids from pink-pigmented methylotrophs].

Science.gov (United States)

Konovalova, A M; Shylin, S O; Rokytko, P V

2006-01-01

An effective method was developed for complete removal of pigments from the cells and solvent mixture for further separation of pigments using thin layer chromatography on silica gel. Carotenoid samples that have been obtained in this way are of good purity for further investigations. Carotenoid pigments of pink-pigmented facultative methylotrophic bacteria Methylobacterium have been characterized. These carotenoids are represented mainly by xanthophylls, particularly hydroxycarotenoids. Strains M. fujisawaense B-3365 and M. mesophilicum B-3352 also have nonpolar carotenes in a small amount. Physico-chemical properties of carotenoids have been studied.

Methylopila capsulata gen. nov., sp. nov., a novel non-pigmented aerobic facultatively methylotrophic bacterium.

Science.gov (United States)

Doronina, N V; Trotsenko, Y A; Krausova, V I; Boulygina, E S; Tourova, T P

1998-10-01

A new genus, Methylopila, and one new species are described for a group of seven strains of facultatively methylotrophic bacteria with the serine pathway of C1 assimilation. These bacteria are aerobic, Gram-negative, non-spore--forming, motile, colourless rods that multiply by binary fission. Their DNA base content ranges from 66 to 70 mol % G + C. Their cellular fatty acid profile consists primarily of C18:1 omega 7 cis-vaccenic and C19:0 cyclopropane acids. The major hydroxy acid is 3-OH C14:0. The main ubiquinone is Q-10. The dominant cellular phospholipids are phosphatidylethanolamine and phosphatidylcholine. The new isolates have a low level of DNA-DNA homology (5-10%) with the type strains of the serine pathway methylobacteria belonging to the genera Methylobacterium, Aminobacter, Hyphomicrobium and Methylorhabdus. Another approach, involving 16S rRNA gene sequence analysis of strain IM1T, has shown that the new isolates represent a separate branch within the alpha-2 subclass of the Proteobacteria. The type species of the new genus is Methylopila capsulata sp. nov., with the type strain IM1T (= VKM B-1606T).

Methylobacterium phyllosphaerae sp. nov., a pink-pigmented, facultative methylotroph from the phyllosphere of rice.

Science.gov (United States)

Madhaiyan, Munusamy; Poonguzhali, Selvaraj; Kwon, Soon-Wo; Sa, Tong-Min

2009-01-01

A pink-pigmented, aerobic, facultatively methylotrophic bacterial strain, CBMB27T, isolated from leaf tissues of rice (Oryza sativa L. 'Dong-Jin'), was analysed using a polyphasic taxonomic approach. Comparative 16S rRNA gene sequence-based phylogenetic analysis placed the strain in a clade with the species Methylobacterium oryzae, Methylobacterium fujisawaense and Methylobacterium mesophilicum; strain CBMB27T showed sequence similarities of 98.3, 98.5 and 97.3 %, respectively, to the type strains of these three species. DNA-DNA hybridization experiments revealed low levels (<38 %) of DNA-DNA relatedness between strain CBMB27T and its closest relatives. The sequence of the 1-aminocyclopropane-1-carboxylate deaminase gene (acdS) in strain CBMB27T differed from those of close relatives. The major fatty acid of the isolate was C(18 : 1)omega7c and the G+C content of the genomic DNA was 66.8 mol%. Based on the results of 16S rRNA gene sequence analysis, DNA-DNA hybridization, and physiological and biochemical characterization, which enabled the isolate to be differentiated from all recognized species of the genus Methylobacterium, it was concluded that strain CBMB27T represents a novel species in the genus Methylobacterium for which the name Methylobacterium phyllosphaerae sp. nov. is proposed (type strain CBMB27T =LMG 24361T =KACC 11716T =DSM 19779T).

Methylopila helvetica sp. nov. and Methylobacterium dichloromethanicum sp. nov.--novel aerobic facultatively methylotrophic bacteria utilizing dichloromethane.

Science.gov (United States)

Doronina, N V; Trotsenko, Y A; Tourova, T P; Kuznetsov, B B; Leisinger, T

2000-06-01

Eight strains of Gram-negative, aerobic, asporogenous, neutrophilic, mesophilic, facultatively methylotrophic bacteria are taxonomically described. These icl- serine pathway methylobacteria utilize dichloromethane, methanol and methylamine as well as a variety of polycarbon compounds as the carbon and energy source. The major cellular fatty acids of the non-pigmented strains DM1, DM3, and DM5 to DM9 are C18:1, C16:0, C18:0, Ccy19:0 and that of the pink-pigmented strain DM4 is C18:1. The main quinone of all the strains is Q-10. The non-pigmented strains have similar phenotypic properties and a high level of DNA-DNA relatedness (81-98%) as determined by hybridization. All strains belong to the alpha-subgroup of the alpha-Proteobacteria. 16S rDNA sequence analysis led to the classification of these dichloromethane-utilizers in the genus Methylopila as a new species - Methylopila helvetica sp.nov. with the type strain DM9 (=VKM B-2189). The pink-pigmented strain DM4 belongs to the genus Methylobacterium but differs from the known members of this genus by some phenotypic properties, DNA-DNA relatedness (14-57%) and 16S rDNA sequence. Strain DM4 is named Methylobacterium dichloromethanicum sp. nov. (VKM B-2191 = DSMZ 6343).

Growth and enzymological characteristics of a pink-pigmented facultative methylotroph Methylobacterium sp. MB1.

Science.gov (United States)

Baev, M V; Kuznetsov, E V; Skladnev, D A; Govorukhina, N I; Sterkin, V E; Tsygankov, Y D

1992-01-01

Growth characteristics of batch and continuous cultures of the pink facultative methylotroph Methylobacterium sp. MB1 were determined. The response of a chemostat culture to a pulse increase of methanol concentration was studied. Malate, succinate and oxaloacetate additions to the methanol-supplemented medium decreased batch culture growth inhibition by methanol. The carotenoid content in cells grown in a chemostat decreased with increasing growth rate. The key enzyme activities of C1-metabolism were measured in a chemostat culture at different dilution rates.

Methylobacillus pratensis sp. nov., a novel non-pigmented, aerobic, obligately methylotrophic bacterium isolated from meadow grass.

Science.gov (United States)

Doronina, Nina V; Trotsenko, Yuri A; Kolganova, Tatjana V; Tourova, Tatjana P; Salkinoja-Salonen, Mirja S

2004-09-01

Strain F31T was isolated from meadow grass (Poa trivialis L.) sampled from the city park in Helsinki. Analysis of phenotypic and genotypic properties showed the strain to be related to the group of obligately methylotrophic non-methane utilizing bacteria (methylobacteria) with the ribulose monophosphate pathway of formaldehyde assimilation. Phylogenetic analysis showed the strain to be closely related to the genus Methylobacillus, and analysis of fatty acid composition confirmed this association. Thus, on the basis of its genotypic and phenotypic properties, the isolate is proposed as a novel species of the genus Methylobacillus, Methylobacillus pratensis sp. nov., with F31T as the type strain (= VKM B-2247T = NCIMB 13994T).

Control of wilt and rot pathogens of tomato by antagonistic pink pigmented facultative methylotrophic Delftia lacustris and Bacillus spp.

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Veeranan Janahiraman

2016-11-01

Full Text Available The studies on the biocontrol potential of pink pigmented facultative methylotrophic (PPFM bacteria other than the genus Methylobacterium are scarce. In the present study, we report three facultative methylotrophic isolates; PPO-1, PPT-1 and PPB-1, respectively identified as Delftia lacustris, Bacillus subtilis and Bacillus cereus by 16S rRNA gene sequence analysis. Hemolytic activity was tested to investigate the potential pathogenicity of isolates to plants and humans, the results indicates that the isolates PPO-1, PPT-1 and PPB-1 are not pathogenic strains. Under in vitro conditions, D. lacustris PPO-1, B. subtilis PPT-1 and B. cereus PPB-1 showed direct antagonistic effect by inhibiting the mycelial growth of fungal pathogens; Fusarium oxysporum f. sp. lycopersici (2.15, 2.05 and 1.95 cm, Sclerotium rolfsii (2.14, 2.04 and1.94 cm, Pythium ultimum (2.12, 2.02 and 1.92cm, and Rhizoctonia solani (2.18, 2.08 and 1.98 cm and also produced volatile inhibitory compounds. Under plant growth chamber condition methylotrophic bacterial isolates; D. lacustris PPO-1, B. subtilis PPT-1 and B. cereus PPB-1 significantly reduced the disease incidence of tomato. Under greenhouse condition, D. lacustris PPO-1, B. subtilis PPT-1 and B. cereus PPB-1 inoculated tomato plants, when challenged with F. oxysporum f. sp. lycopersici, S. rolfsii, P. ultimum and R. solani, increased the pathogenesis related proteins (β-1, 3-glucanase and chitinase and defense enzymes (phenylalanine ammonia lyase, peroxidase, polyphenol oxidase, and catalase on day 5 after inoculation. In the current study, we first report the facultative methylotrophy in pink pigmented Delftia lacustris, B. subtilis, and B. cereus and their antagonistic potential against fungal pathogens. Direct antagonistic and ISR effects of these isolates against fungal pathogens of tomato evidenced their possible use as a biocontrol agent.

Peculiarities of glucose and glycerol metabolism in Nocardia vaccinii IMB B-7405

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T. P. Pirog

2015-04-01

Full Text Available It has been established that in cells of Nocardia vaccinii IMB B-7405 (surfactant producer glucose catabolism is performed through pentose phosphate cycle as well as through gluconate (activi­ty of NAD+-dependent glucose-6- phosphate dehydrogenase and FAD+-dependent glucose dehydrogenase 835 ± 41 and 698 ± 35 nmol∙min-1∙mg-1 of protein respectively. 6-Phosphogluconate formed in the gluconokinase reaction is involved in the pentose phosphate cycle (activity of constitutive NADP+-dependent 6-phosphogluconate dehydrogenase 357 ± 17 nmol∙min-1∙mg-1 of protein. Glyce­rol catabolism to dihydroxyacetonephosphate (the intermediate of glycolysis may be performed in two ways: through glycerol-3-phosphate (glycerol kinase activity 244 ± 12 nmol∙min-1∙mg-1 of protein and through dihydroxyacetone. Replenishment of the C4-dicarboxylic acids pool in N. vaccinii IMV B-7405 grown on glucose and glycerol occurs in the phosphoenolpyruvate(PEPcarboxylase reaction (714–803 nmol∙min-1∙mg-1 of protein. 2-Oxoglutara­te was involved in tricarboxylic acid cycle by alternate pathway with the participation of 2-oxoglutarate synthase. The observed activity of both key enzymes of gluconeogenesis (PEP- carboxykinase and PEP-synthase, trehalose phosphate synthase and NADP+-dependent glutamate dehydrogenase confirmed the ability of IMV B-7405 strain to the synthesis of surface active glyco- and aminolipids, respectively.

A Novel Methylotrophic Bacterial Consortium for Treatment of Industrial Effluents.

Science.gov (United States)

Hingurao, Krushi; Nerurkar, Anuradha

2018-01-01

Considering the importance of methylotrophs in industrial wastewater treatment, focus of the present study was on utilization of a methylotrophic bacterial consortium as a microbial seed for biotreatment of a variety of industrial effluents. For this purpose, a mixed bacterial methylotrophic AC (Ankleshwar CETP) consortium comprising of Bordetella petrii AC1, Bacillus licheniformis AC4, Salmonella subterranea AC5, and Pseudomonas stutzeri AC8 was used. The AC consortium showed efficient biotreatment of four industrial effluents procured from fertilizer, chemical and pesticide industries, and common effluent treatment plant by lowering their chemical oxygen demand (COD) of 950-2000 mg/l to below detection limit in 60-96 h in 6-l batch reactor and 9-15 days in 6-l continuous reactor. The operating variables of wastewater treatment, viz. COD, BOD, pH, MLSS, MLVSS, SVI, and F/M ratio of these effluents, were also maintained in the permissible range in both batch and continuous reactors. Therefore, formation of the AC consortium has led to the development of an efficient microbial seed capable of treating a variety of industrial effluents containing pollutants generated from their respective industries.

Use of oligodeoxynucleotide signature probes for identification of physiological groups of methylotrophic bacteria

International Nuclear Information System (INIS)

Tsien, H.C.; Bratina, B.J.; Tsuji, K.; Hanson, R.S.

1990-01-01

Oligodeoxynucleotide sequences that uniquely complemented 16S rRNAs of each group of methylotrophs were synthesized and used as hybridization probes for the identification of methylotrophic bacteria possessing the serine and ribulose monophosphate (RuMP) pathways for formaldehyde fixation. The specificity of the probes was determined by hybridizing radiolabeled probes with slot-blotted RNAs of methylotrophs and other eubacteria followed by autoradiography. The washing temperature was determined experimentally to be 50 and 52 degrees C for 9-α (serine pathway) and 10-γ (RuMP pathway) probes, respectively. RNAs isolated from serine pathway methylotrophs bound to probe 9-α, and RNAs from RuMP pathway methylotrophs bound to probe 10-γ. Nonmethylotrophic eubacterial RNAs did not bind to either probe. The probes were also labeled with fluorescent dyes. Cells fixed to microscope slides were hybridized with these probes, washed, and examined in a fluorescence microscope equipped with appropriate filter sets. Cells of methylotrophic bacteria possessing the serine or RuMP pathway specifically bind probes designed for each group. Samples with a mixture of cells of type I and II methanotrophs were detected and differentiated with single probes or mixed probes labeled with different fluorescent dyes, which enabled the detection of both types of cells in the same microscopic field

Production of polyhydroxyalkanoates from methanol by a new methylotrophic bacterium Methylobacterium sp. GW2.

Science.gov (United States)

Yezza, A; Fournier, D; Halasz, A; Hawari, J

2006-11-01

A new bacterial strain, isolated from groundwater contaminated with explosives, was characterized as a pink-pigmented facultative methylotroph, affiliated to the genus Methylobacterium. The bacterial isolate designated as strain GW2 was found capable of producing the homopolymer poly-3-hydroxybutyrate (PHB) from various carbon sources such as methanol, ethanol, and succinate. Methanol acted as the best substrate for the production of PHB reaching 40 % w/w dry biomass. PHB accumulation was observed to be a growth-associated process, so that there was no need for two-step fermentation. Optimal growth occurred at 0.5 % (v/v) methanol concentration, and growth was strongly inhibited at alpha concentration above 2 % (v/v). Methylobacterium sp. strain GW2 was also able to accumulate the copolyester poly-3-hydroxybutyrate-poly-3-hydroxyvalerate (PHB/HV) when valeric acid was supplied as an auxiliary carbon source to methanol. After 66 h, a copolymer content of 30 % (w/w) was achieved with a PHB to PHV ratio of 1:2. Biopolymers produced by strain GW2 had an average molecular weight ranging from 229,350 to 233,050 Da for homopolymer PHB and from 362,430 to 411,300 Da for the copolymer PHB/HV.

IMB2026791, a Xanthone, Stimulates Cholesterol Efflux by Increasing the Binding of Apolipoprotein A-I to ATP-Binding Cassette Transporter A1

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Zijian Xie

2012-03-01

Full Text Available It is known that the ATP-binding cassette transporter A1 (ABCA1 plays a major role in cholesterol homeostasis and high density lipoprotein (HDL metabolism. Several laboratories have demonstrated that ABCA1 binding to lipid-poor apolipoprotein A-I (apoA-I will mediate the assembly of nascent HDL and cellular cholesterol efflux, which suggests a possible receptor-ligand interaction between ABCA1 and apoA-I. In this study, a cell-based-ELISA-like high-throughput screening (HTS method was developed to identify the synthetic and natural compounds that can regulate binding activity of ABCA1 to apoA-I. The cell-based-ELISA-like high-throughput screen was conducted in a 96-well format using Chinese hamster ovary (CHO cells stably transfected with ABCA1 pIRE2-EGFP (Enhanced Green Fluorecence Protein expression vector and the known ABCA1 inhibitor glibenclamide as the antagonist control. From 2,600 compounds, a xanthone compound (IMB 2026791 was selected using this HTS assay, and it was proved as an apoA-I binding agonist to ABCA1 by a flow cytometry assay and western blot analysis. The [3H] cholesterol efflux assay of IMB2026791 treated ABCA1-CHO cells and PMA induced THP-1 macrophages (human acute monocytic leukemia cell further confirmed the compound as an accelerator of cholesterol efflux in a dose-dependent manner with an EC50 of 25.23 μM.

In vivo unnatural amino acid expression in the methylotrophic yeast Pichia pastoris

Energy Technology Data Exchange (ETDEWEB)

Young, Travis; Schultz, Peter G.

2017-08-15

The invention provides orthogonal translation systems for the production of polypeptides comprising unnatural amino acids in methylotrophic yeast such as Pichia pastoris. Methods for producing polypeptides comprising unnatural amino acids in methylotrophic yeast such as Pichia pastoris are also provided.

Methylobacterium marchantiae sp. nov., a pink-pigmented, facultatively methylotrophic bacterium isolated from the thallus of a liverwort.

Science.gov (United States)

Schauer, S; Kämpfer, P; Wellner, S; Spröer, C; Kutschera, U

2011-04-01

A pink-pigmented, facultatively methylotrophic bacterium, designated strain JT1(T), was isolated from a thallus of the liverwort Marchantia polymorpha L. and was analysed by using a polyphasic approach. Comparative 16S rRNA gene sequence analysis placed the strain in a clade with Methylobacterium adhaesivum AR27(T), Methylobacterium fujisawaense DSM 5686(T), Methylobacterium radiotolerans JCM 2831(T) and Methylobacterium jeotgali S2R03-9(T), with which it showed sequence similarities of 97.8, 97.7, 97.2 and 97.4 %, respectively. However, levels of DNA-DNA relatedness between strain JT1(T) and these and the type strains of other closely related species were lower than 70 %. Cells of JT1(T) stained Gram-negative and were motile, rod-shaped and characterized by numerous fimbriae-like appendages on the outer surface of their wall (density up to 200 µm(-2)). Major fatty acids were C(18 : 1)ω7c and C(16 : 0). Based on the morphological, physiological and biochemical data presented, strain JT1(T) is considered to represent a novel species of the genus Methylobacterium, for which the name Methylobacterium marchantiae sp. nov. is proposed. The type strain is JT1(T) ( = DSM 21328(T)  = CCUG 56108(T)).

Purification of methanol dehydrogenase from mouth methylotrophic bacteria of tropical region

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Waturangi, D.

2011-01-01

Full Text Available Aims: Purification of methanol dehydrogenase (MDH from methylotrophic bacteria was conducted to obtain pure enzyme for further research and industrial applications due to the enzyme’s unique activity that catalyzes oxidation of methanol as an important carbon source in methylotrophic bacteria.Methodology and Results: The enzyme was screened from methylotrophic bacteria isolated from human mouth. Purification of this enzyme was conducted using ammonium sulphate precipitation followed by cation exchange chromatography. Two types of media were used to produce the enzymes: luria broth and standard mineral salts media (MSM. MSM produced MDH with higher specific activity than LB. Specific activity was also increased along with the purification steps. Application of ammonium sulphate increased the purity of enzyme and was more effective for the enzyme produced in LB. Using sepharose increased the enzyme activity 10 -57 folds.Conclusion, significant and impact of this study: With this, ammonium sulphate precipitation coupled with single cation exchange chromatographic system has been proved to provide sufficient purified of methanol dehydrogenase from methylotrophic bacteria origin of human mouth with high specific activity for further application.

Rapid detection of food-borne Salmonella contamination using IMBs-qPCR method based on pagC gene

Directory of Open Access Journals (Sweden)

Jiashun Wang

Full Text Available Abstract Detection of Salmonella is very important to minimize the food safety risk. In this study, the recombinant PagC protein and PagC antibody were prepared and coupled with immunomagnetic beads (IMBs to capture Salmonella cells from pork and milk samples. And then the SYBR Green qualitative PCR was developed to detect the pathogenic Salmonella. The results showed that the PagC polyclonal antiserum is of good specificity and the capture rate of 0.1 mg IMBs for Salmonella tended to be stable at the range of 70-74% corresponding to the concentrations between 101 and 104 CFU/mL. The method developed demonstrated high specificity for the positive Salmonella samples when compared to non-specific DNA samples, such as Escherichia coli, Staphylococcus aureus, Yersinia enterocolitica, and Yersinia pseudotuberculosis. The limit of detection of this assay was 18 CFU/mL. Detection and quantitative enumeration of Salmonella in samples of pork or milk shows good recoveries of 54.34% and 52.07%. In conclusion, the polyclonal antibody of recombinant PagC protein is effective to capture Salmonella from detected samples. The developed pagC antibody IMBs-qPCR method showed efficiency, sensitivity and specificity for 30 Salmonella detection, enabling detection within 10 h, which is a promising rapid method to detect Salmonella in emergency.

Predicting Condom Use Using the Information-Motivation-Behavioral Skills (IMB) Model: A Multivariate Latent Growth Curve Analysis

Science.gov (United States)

Senn, Theresa E.; Scott-Sheldon, Lori A. J.; Vanable, Peter A.; Carey, Michael P.

2011-01-01

Background The Information-Motivation-Behavioral Skills (IMB) model often guides sexual risk reduction programs even though no studies have examined covariation in the theory’s constructs in a dynamic fashion with longitudinal data. Purpose Using new developments in latent growth modeling, we explore how changes in information, motivation, and behavioral skills over 9 months relate to changes in condom use among STD clinic patients. Methods Participants (N = 1281, 50% female, 66% African American) completed measures of IMB constructs at three time points. We used parallel process latent growth modeling to examine associations among intercepts and slopes of IMB constructs. Results Initial levels of motivation, behavioral skills, and condom use were all positively associated, with behavioral skills partially mediating associations between motivation and condom use. Changes over time in behavioral skills positively related to changes in condom use. Conclusions Results support the key role of behavioral skills in sexual risk reduction, suggesting these skills should be targeted in HIV prevention interventions. PMID:21638196

Arthrobacter P 1, a Fast Growing Versatile Methylotroph with Amine Oxidase as a Key Enzyme in the Metabolism of Methylated Amines

NARCIS (Netherlands)

Dijken, J.P. van; Veenhuis, M.; Harder, W.

1981-01-01

A facultative methylotrophic bacterium was isolated from enrichment cultures containing methylamine as the sole carbon source. It was tentatively identified as an Arthrobacter species. Extracts of cells grown on methylamine or ethylamine contained high levels of amine oxidase (E.C. 1.4.3) activity.

Control of Wilt and Rot Pathogens of Tomato by Antagonistic Pink Pigmented Facultative Methylotrophic Delftia lacustris and Bacillus spp.

OpenAIRE

Janahiraman, Veeranan; Anandham, Rangasamy; Kwon, Soon W.; Sundaram, Subbiah; Karthik Pandi, Veeranan; Krishnamoorthy, Ramasamy; Kim, Kiyoon; Samaddar, Sandipan; Sa, Tongmin

2016-01-01

The studies on the biocontrol potential of pink pigmented facultative methylotrophic (PPFM) bacteria other than the genus Methylobacterium are scarce. In the present study, we report three facultative methylotrophic isolates; PPO-1, PPT-1 and PPB-1, respectively identified as Delftia lacustris, Bacillus subtilis and Bacillus cereus by 16S rRNA gene sequence analysis. Hemolytic activity was tested to investigate the potential pathogenicity of isolates to plants and humans, the results indicate...

Unique C-terminal region of Hap3 is required for methanol-regulated gene expression in the methylotrophic yeast Candida boidinii.

Science.gov (United States)

Oda, Saori; Yurimoto, Hiroya; Nitta, Nobuhisa; Sakai, Yasuyoshi

2016-05-01

The Hap complex of the methylotrophic yeast Candida boidinii was found to be required for methanol-regulated gene expression. In this study, we performed functional characterization of CbHap3p, one of the Hap complex components in C. boidinii. Sequence alignment of Hap3 proteins revealed the presence of a unique extended C-terminal region, which is not present in Hap3p from Saccharomyces cerevisiae (ScHap3p), but is found in Hap3p proteins of methylotrophic yeasts. Deletion of the C-terminal region of CbHap3p (Δ256-292 or Δ107-237) diminished activation of methanol-regulated genes and abolished the ability to grow on methanol, but did not affect nuclear localization or DNA-binding ability. However, deletion of the N-terminal region of CbHap3p (Δ1-20) led to not only a growth defect on methanol and a decreased level of methanol-regulated gene expression, but also impaired nuclear localization and binding to methanol-regulated gene promoters. We also revealed that CbHap3p could complement the growth defect of the Schap3Δ strain on glycerol, although ScHap3p could not complement the growth defect of a Cbhap3Δ strain on methanol. We conclude that the unique C-terminal region of CbHap3p contributes to maximum activation of methanol-regulated genes, whilst the N-terminal region is required for nuclear localization and binding to DNA.

A Hexose Transporter Homologue Controls Glucose Repression in the Methylotrophic Yeast Hansenula polymorpha

NARCIS (Netherlands)

Stasyk, Oleh V.; Stasyk, Olena G.; Komduur, Janet; Veenhuis, Marten; Cregg, James M.; Sibirny, Andrei A.

2004-01-01

Peroxisome biogenesis and synthesis of peroxisomal enzymes in the methylotrophic yeast Hansenula polymorpha are under the strict control of glucose repression. We identified an H. polymorpha glucose catabolite repression gene (HpGCR1) that encodes a hexose transporter homologue. Deficiency in GCR1

Predictors of intention to smoke among junior high school students in Shanghai, China: an empirical test of the information-motivation-behavioral skills (IMB) model.

Science.gov (United States)

Zhu, Chendi; Cai, Yong; Ma, Jin; Li, Na; Zhu, Jingfen; He, Yaping; Redmon, Pamela; Qiao, Yun

2013-01-01

Adolescent smoking is a worldwide problem that is particularly severe in low- and middle-income countries. Many endogenous and environmental factors affect the intention to smoke, so a comprehensive model is needed to understand the significance and relationship of predictors. The study aimed to test the associations among information-motivation-behavioral skills (IMB) model constructs as predictors of intention to smoke in junior high school students in Shanghai, China. We conducted a cross-sectional study of 16,500 junior high school students in Shanghai, China. Data on tobacco-related information, motivation, behavioral skills, and behaviors were collected from students. Structural equation model (SEM) was used to assess the IMB model. The mean age of participants was 13.8 years old (standard deviation = 1.02; range 11-17). The experimental smoking rate among junior high school students was 6.6% and 8.7% of the participants expected that they would be smokers in 5 years. The IMB model provided acceptable fit to the data (comparative fit index = 0.984, root mean square error of approximation = 0.04). Intention to smoke was predicted by behavioral skills (β = 0.670, P motivation (β = 0.095, Pschool students. The IMB model provides a good understanding of the predictors of intention to smoke and it suggests future interventions among junior high school students should focus on improving motivation and behavioral skills.

Metabolite profiling uncovers plasmid-induced cobalt limitation under methylotrophic growth conditions.

Directory of Open Access Journals (Sweden)

Patrick Kiefer

2009-11-01

Full Text Available The introduction and maintenance of plasmids in cells is often associated with a reduction of growth rate. The reason for this growth reduction is unclear in many cases.We observed a surprisingly large reduction in growth rate of about 50% of Methylobacterium extorquens AM1 during methylotrophic growth in the presence of a plasmid, pCM80 expressing the tetA gene, relative to the wild-type. A less pronounced growth delay during growth under non-methylotrophic growth conditions was observed; this suggested an inhibition of one-carbon metabolism rather than a general growth inhibition or metabolic burden. Metabolome analyses revealed an increase in pool sizes of ethylmalonyl-CoA and methylmalonyl-CoA of more than 6- and 35-fold, respectively, relative to wild type, suggesting a strongly reduced conversion of these central intermediates, which are essential for glyoxylate regeneration in this model methylotroph. Similar results were found for M. extorquens AM1 pCM160 which confers kanamycin resistance. These intermediates of the ethylmalonyl-CoA pathway have in common their conversion by coenzyme B(12-dependent mutases, which have cobalt as a central ligand. The one-carbon metabolism-related growth delay was restored by providing higher cobalt concentrations, by heterologous expression of isocitrate lyase as an alternative path for glyoxylate regeneration, or by identification and overproduction of proteins involved in cobalt import.This study demonstrates that the introduction of the plasmids leads to an apparent inhibition of the cobalt-dependent enzymes of the ethylmalonyl-CoA pathway. Possible explanations are presented and point to a limited cobalt concentration in the cell as a consequence of the antibiotic stress.

A Study on the Application of the Information-Motivation-Behavioral Skills (IMB Model on Rational Drug Use Behavior among Second-Level Hospital Outpatients in Anhui, China.

Directory of Open Access Journals (Sweden)

Cheng Bian

Full Text Available The high prevalence of risky irrational drug use behaviors mean that outpatients face high risks of drug resistance and even death. This study represents the first application of the Information-Motivation-Behavioral Skills (IMB model on rational drug use behavior among second-level hospital outpatients from three prefecture-level cities in Anhui, China. Using the IMB model, our study examined predictors of rational drug use behavior and determined the associations between the model constructs.This study was conducted with a sample of 1,214 outpatients aged 18 years and older in Anhui second-level hospitals and applied the structural equation model (SEM to test predictive relations among the IMB model variables related to rational drug use behavior.Age, information and motivation had significant direct effects on rational drug use behavior. Behavioral skills as an intermediate variable also significantly predicted more rational drug use behavior. Female gender, higher educational level, more information and more motivation predicted more behavioral skills. In addition, there were significant indirect impacts on rational drug use behavior mediated through behavioral skills.The IMB-based model explained the relationships between the constructs and rational drug use behavior of outpatients in detail, and it suggests that future interventions among second-level hospital outpatients should consider demographic characteristics and should focus on improving motivation and behavioral skills in addition to the publicity of knowledge.

A Study on the Application of the Information-Motivation-Behavioral Skills (IMB) Model on Rational Drug Use Behavior among Second-Level Hospital Outpatients in Anhui, China.

Science.gov (United States)

Bian, Cheng; Xu, Shuman; Wang, Heng; Li, Niannian; Wu, Jingya; Zhao, Yunwu; Li, Peng; Lu, Hua

2015-01-01

The high prevalence of risky irrational drug use behaviors mean that outpatients face high risks of drug resistance and even death. This study represents the first application of the Information-Motivation-Behavioral Skills (IMB) model on rational drug use behavior among second-level hospital outpatients from three prefecture-level cities in Anhui, China. Using the IMB model, our study examined predictors of rational drug use behavior and determined the associations between the model constructs. This study was conducted with a sample of 1,214 outpatients aged 18 years and older in Anhui second-level hospitals and applied the structural equation model (SEM) to test predictive relations among the IMB model variables related to rational drug use behavior. Age, information and motivation had significant direct effects on rational drug use behavior. Behavioral skills as an intermediate variable also significantly predicted more rational drug use behavior. Female gender, higher educational level, more information and more motivation predicted more behavioral skills. In addition, there were significant indirect impacts on rational drug use behavior mediated through behavioral skills. The IMB-based model explained the relationships between the constructs and rational drug use behavior of outpatients in detail, and it suggests that future interventions among second-level hospital outpatients should consider demographic characteristics and should focus on improving motivation and behavioral skills in addition to the publicity of knowledge.

Methylotrophic methanogenesis governs the biogenic coal bed methane formation in Eastern Ordos Basin, China

Energy Technology Data Exchange (ETDEWEB)

Guo, Hongguang; Yu, Zhisheng; Liu, Ruyin [Graduate Univ. of Chinese Academy of Sciences, Beijing (China). College of Resources and Environment; Zhang, Hongxun [Graduate Univ. of Chinese Academy of Sciences, Beijing (China). College of Resources and Environment; Chinese Academy of Sciences, Beijing (China). Research Center for Eco-Environmental Sciences; Zhong, Qiding; Xiong, Zhenghe [China National Research Institute of Food and Fermentation Industries, Beijing (China). Food Analysis using Isotope Technology Lab

2012-12-15

To identify the methanogenic pathways present in a deep coal bed methane (CBM) reservoir associated with Eastern Ordos Basin in China, a series of geochemical and microbiological studies was performed using gas and water samples produced from the Liulin CBM reservoir. The composition and stable isotopic ratios of CBM implied a mixed biogenic and thermogenic origin of the methane. Archaeal 16S rRNA gene analysis revealed the dominance of the methylotrophic methanogen Methanolobus in the water produced. The high potential of methane production by methylotrophic methanogens was found in the enrichments using the water samples amended with methanol and incubated at 25 and 35 C. Methylotrophic methanogens were the dominant archaea in both enrichments as shown by polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE). Bacterial 16S rRNA gene analysis revealed that fermentative, sulfate-reducing, and nitrate-reducing bacteria inhabiting the water produced were a factor in coal biodegradation to fuel methanogens. These results suggested that past and ongoing biodegradation of coal by methylotrophic methanogens and syntrophic bacteria, as well as thermogenic CBM production, contributed to the Liulin CBM reserves associated with the Eastern Ordos Basin. (orig.)

[The regulation of peroxisomal matrix enzymes (alcohol oxidase and catalase) formation by the product of the gene Mth1 in methylotrophic yeast Pichia methanolica].

Science.gov (United States)

Leonovich, O A; Kurales, Iu A; Dutova, T A; Isakova, E P; Deriabina, Iu I; Rabinovich, Ia M

2009-01-01

Two independent mutant strains of methylotrophic yeast Pichia methanolica (mth1 arg1 and mth2 arg4) from the initial line 616 (ade1 ade5) were investigated. The mutant strains possessed defects in genes MTH1 and MTH2 which resulted in the inability to assimilate methanol as a sole carbon source and the increased activity of alcohol oxidase (AO). The function of the AUG2 gene encoding one of the subunits of AO and CTA1, a probable homolog of peroxisomal catalase of Saccharomyces cereviseae, was investigated by analyses of the molecular forms of isoenzymes. It was shown that optimal conditions for the expression of the AUG2 gene on a medium supplemented with 3% of methanol leads to an increasing synthesis of peroxisomal catalase. The mutant mth1 possessed a dominant formation of AO isoform with electrophoretic mobility which is typical for isogenic form 9, the product of the AUG2 gene, and a decreased level of peroxisomal catalase. The restoration of growth of four spontaneous revertants of the mutant mth1 (Rmth1) on the methanol containing medium was accompanied by an increase in activity of AO isogenic form 9 and peroxisomal catalase. The obtained results confirmed the functional continuity of the structural gene AUG2 in mutant mth1. The correlation of activity of peroxisomal catalase and AO isogenic form 1 in different conditions evidenced the existence of common regulatory elements for genes AUG2 and CTA1 in methilotrophic yeast Pichia methanolica.

The diversity of endophytic methylotrophic bacteria in an oil-contaminated and an oil-free mangrove ecosystem and their tolerance to heavy metals.

Science.gov (United States)

Dourado, Manuella Nobrega; Ferreira, Anderson; Araújo, Welington Luiz; Azevedo, João Lúcio; Lacava, Paulo Teixeira

2012-01-01

Methylobacterium strains were isolated from mangrove samples collected in Bertioga, SP, Brazil, from locations either contaminated or uncontaminated by oil spills. The tolerances of the strains to different heavy metals were assessed by exposing them to different concentrations of cadmium, lead, and arsenic (0.1 mM, 0.5 mM, 1 mM, 2 mM, 4 mM, and 8 mM). Additionally, the genetic diversity of Methylobacterium spp. was determined by sequence analysis of the 16S rRNA genes. The isolates from the contaminated locations were grouped, suggesting that oil can select for microorganisms that tolerate oil components and can change the methylotrophic bacterial community. Cadmium is the most toxic heavy metal assessed in this work, followed by arsenic and lead, and two isolates of Methylobacterium were found to be tolerant to all three metals. These isolates have the potential to bioremediate mangrove environments contaminated by oil spills by immobilizing the heavy metals present in the oil.

Biotechnological and agronomic potential of endophytic pink-pigmented methylotrophic Methylobacterium spp.

Science.gov (United States)

Dourado, Manuella Nóbrega; Camargo Neves, Aline Aparecida; Santos, Daiene Souza; Araújo, Welington Luiz

2015-01-01

The genus Methylobacterium is composed of pink-pigmented facultative methylotrophic (PPFM) bacteria, which are able to synthesize carotenoids and grow on reduced organic compounds containing one carbon (C1), such as methanol and methylamine. Due to their high phenotypic plasticity, these bacteria are able to colonize different habitats, such as soil, water, and sediment, and different host plants as both endophytes and epiphytes. In plant colonization, the frequency and distribution may be influenced by plant genotype or by interactions with other associated microorganisms, which may result in increasing plant fitness. In this review, different aspects of interactions with the host plant are discussed, including their capacity to fix nitrogen, nodule the host plant, produce cytokinins, auxin and enzymes involved in the induction of systemic resistance, such as pectinase and cellulase, and therefore plant growth promotion. In addition, bacteria belonging to this group can be used to reduce environmental contamination because they are able to degrade toxic compounds, tolerate high heavy metal concentrations, and increase plant tolerance to these compounds. Moreover, genome sequencing and omics approaches have revealed genes related to plant-bacteria interactions that may be important for developing strains able to promote plant growth and protection against phytopathogens.

Measurement of atmospheric neutrino composition with the IMB-3 detector

International Nuclear Information System (INIS)

Casper, D.; Becker-Szendy, R.; Bratton, C.B.; Cady, D.R.; Claus, R.; Dye, S.T.; Gajewski, W.; Goldhaber, M.; Haines, T.J.; Halverson, P.G.; Jones, T.W.; Kielczewska, D.; Kropp, W.R.; Learned, J.G.; LoSecco, J.M.; McGrew, C.; Matsuno, S.; Matthews, J.; Mudan, M.S.; Price, L.; Reines, F.; Schultz, J.; Sinclair, D.; Sobel, H.W.; Stone, J.L.; Sulak, L.R.; Svoboda, R.; Thornton, G.; van der Velde, J.C.; The University of Michigan, Ann Arbor, Michigan 48109 Brookhaven National; Laboratory, Upton, New York 11973; Boston University, Boston, Massachusetts 02215; The University of Hawaii, Honolulu, Hawaii 96822 University College, London, WC1E F6BT, United Kingdom; Warsaw University, Warsaw, Poland; Cleveland State University, Cleveland, Ohio 44115; The University of Notre Dame, Notre Dame, Indiana 46556; Lousiana State University, Baton Rouge, Lousisiana 70803; The University of Maryland, College Park, Maryland 20742)

1991-01-01

The atmospheric neutrino flux is measured using a 3.4-kt yr exposure of the IMB-3 detector. Single-ring events are classified as showering or nonshowering using the geometry of the Cerenkov pattern. A simulation of neutrino interactions and three models of atmospheric neutrino production are used to predict the composition of the sample. Showering-nonshowering character is strongly correlated with the flavor of the neutrino parent. In the lepton momentum range p<1500 MeV/c, we find that nonshowering events comprise [41±3±2syst]% of the total. The fraction expected is [51±5(syst)]%

Albibacter methylovorans gen. nov., sp. nov., a novel aerobic, facultatively autotrophic and methylotrophic bacterium that utilizes dichloromethane.

Science.gov (United States)

Doronina, N V; Trotsenko, Y A; Tourova, T P; Kuznetsov, B B; Leisinger, T

2001-05-01

A novel genus, Albibacter, with one species, Albibacter methylovorans sp. nov., is proposed for a facultatively chemolithotrophic and methylotrophic bacterium (strain DM10T) with the ribulose bisphosphate (RuBP) pathway of C1 assimilation. The bacterium is a Gram-negative, aerobic, asporogenous, nonmotile, colourless rod that multiplies by binary fission. The organism utilizes dichloromethane, methanol, methylamine, formate and CO2/H2, as well as a variety of polycarbon compounds, as carbon and energy sources. It is neutrophilic and mesophilic. The major cellular fatty acids are straight-chain unsaturated C18:1, saturated C16:0 and cyclopropane C19:0 acids. The main ubiquinone is Q-10. The dominant phospholipids are phosphatidyl ethanolamine, phosphatidyl glycerol, phosphatidyl choline and cardiolipin. The DNA G+C content is 66.7 mol%. Strain DM10T has a very low degree of DNA-DNA hybridization (4-7%) with the type species of the genera Paracoccus, Xanthobacter, Blastobacter, Angulomicrobium, Ancylobacter and Ralstonia of RuBP pathway methylobacteria. Another approach, involving comparative 16S rDNA analysis, has shown that the novel isolate represents a separate branch within the alpha-2 subgroup of the Proteobacteria. The type species of the new genus is Albibacter methylovorans sp. nov.; the type strain is DM10T (= VKM B-2236T = DSM 13819T).

Biotechnological and Agronomic Potential of Endophytic Pink-Pigmented Methylotrophic Methylobacterium spp.

OpenAIRE

Dourado, Manuella Nóbrega; Aparecida Camargo Neves, Aline; Santos, Daiene Souza; Araújo, Welington Luiz

2015-01-01

The genus Methylobacterium is composed of pink-pigmented facultative methylotrophic (PPFM) bacteria, which are able to synthesize carotenoids and grow on reduced organic compounds containing one carbon (C1), such as methanol and methylamine. Due to their high phenotypic plasticity, these bacteria are able to colonize different habitats, such as soil, water, and sediment, and different host plants as both endophytes and epiphytes. In plant colonization, the frequency and distribution may be in...

Identification of active methylotroph populations in an acidic forest soil by stable-isotope probing.

Science.gov (United States)

Radajewski, Stefan; Webster, Gordon; Reay, David S; Morris, Samantha A; Ineson, Philip; Nedwell, David B; Prosser, James I; Murrell, J Colin

2002-08-01

Stable-isotope probing (SIP) is a culture-independent technique that enables the isolation of DNA from micro-organisms that are actively involved in a specific metabolic process. In this study, SIP was used to characterize the active methylotroph populations in forest soil (pH 3.5) microcosms that were exposed to (13)CH(3)OH or (13)CH(4). Distinct (13)C-labelled DNA ((13)C-DNA) fractions were resolved from total community DNA by CsCl density-gradient centrifugation. Analysis of 16S rDNA sequences amplified from the (13)C-DNA revealed that bacteria related to the genera Methylocella, Methylocapsa, Methylocystis and Rhodoblastus had assimilated the (13)C-labelled substrates, which suggested that moderately acidophilic methylotroph populations were active in the microcosms. Enrichments targeted towards the active proteobacterial CH(3)OH utilizers were successful, although none of these bacteria were isolated into pure culture. A parallel analysis of genes encoding the key enzymes methanol dehydrogenase and particulate methane monooxygenase reflected the 16S rDNA analysis, but unexpectedly revealed sequences related to the ammonia monooxygenase of ammonia-oxidizing bacteria (AOB) from the beta-subclass of the PROTEOBACTERIA: Analysis of AOB-selective 16S rDNA amplification products identified Nitrosomonas and Nitrosospira sequences in the (13)C-DNA fractions, suggesting certain AOB assimilated a significant proportion of (13)CO(2), possibly through a close physical and/or nutritional association with the active methylotrophs. Other sequences retrieved from the (13)C-DNA were related to the 16S rDNA sequences of members of the Acidobacterium division, the beta-Proteobacteria and the order Cytophagales, which implicated these bacteria in the assimilation of reduced one-carbon compounds or in the assimilation of the by-products of methylotrophic carbon metabolism. Results from the (13)CH(3)OH and (13)CH(4) SIP experiments thus provide a rational basis for further

The Diversity of Endophytic Methylotrophic Bacteria in an Oil-Contaminated and an Oil-Free Mangrove Ecosystem and Their Tolerance to Heavy Metals

Science.gov (United States)

Dourado, Manuella Nobrega; Ferreira, Anderson; Araújo, Welington Luiz; Azevedo, João Lúcio; Lacava, Paulo Teixeira

2012-01-01

Methylobacterium strains were isolated from mangrove samples collected in Bertioga, SP, Brazil, from locations either contaminated or uncontaminated by oil spills. The tolerances of the strains to different heavy metals were assessed by exposing them to different concentrations of cadmium, lead, and arsenic (0.1 mM, 0.5 mM, 1 mM, 2 mM, 4 mM, and 8 mM). Additionally, the genetic diversity of Methylobacterium spp. was determined by sequence analysis of the 16S rRNA genes. The isolates from the contaminated locations were grouped, suggesting that oil can select for microorganisms that tolerate oil components and can change the methylotrophic bacterial community. Cadmium is the most toxic heavy metal assessed in this work, followed by arsenic and lead, and two isolates of Methylobacterium were found to be tolerant to all three metals. These isolates have the potential to bioremediate mangrove environments contaminated by oil spills by immobilizing the heavy metals present in the oil. PMID:22482056

Experimental Neutrino Physics and Astrophysics with the IMB-3 Detector

Science.gov (United States)

Casper, David William

1990-01-01

Description of the universe on the smallest (elementary particle physics) and largest (cosmology) scales has become dependent on the properties of the most weakly interacting fundamental particle known, the neutrino. The IMB experiment, designed to study nucleon decay, is also the world's largest detector of neutrinos. The experiment uses 6800 tons (3300 tons fiducial) of water as both target and detecting medium. Relativistic charges particles traversing the water radiate Cerenkov light. The distinctive ring patterns are imaged by 2048 light collectors (each a photo-multiplier tube coupled with a wavelength-shifting plate) distributed over the surfaces of the tank. This dissertation describes the IMB-3 detector, a four-fold increase in sensitivity over the original apparatus. Neutrino interactions of both atmospheric and extragalactic origin were collected during a 3.4 kiloton-year exposure. A consequence of non-zero neutrino mass could be oscillation of neutrino flavor. The energies and long flight distances of atmospheric neutrinos offer a unique opportunity to explore this possibility. To study the composition of the atmospheric neutrinos, single-ring events are classified as showering or non-showering using the geometry of the Cerenkov pattern. A simulation of neutrino interactions and a model of atmospheric neutrino production are used to predict the composition of the sample. The showering/non-showering character of an event is strongly correlated with the flavor of its neutrino parent. In the lepton momentum range p mass or "dark matter" problem result in high-energy neutrino production within the Sun. A model of dark matter capture and annihilation in the Sun predicts the resulting neutrino fluxes at Earth. No evidence of the phenomenon is observed, but for canonical values of dark matter density and velocity in the solar system, greater exposure will be required to verify or exclude the expected signal.

Biotechnological and Agronomic Potential of Endophytic Pink-Pigmented Methylotrophic Methylobacterium spp.

Directory of Open Access Journals (Sweden)

Manuella Nóbrega Dourado

2015-01-01

Full Text Available The genus Methylobacterium is composed of pink-pigmented facultative methylotrophic (PPFM bacteria, which are able to synthesize carotenoids and grow on reduced organic compounds containing one carbon (C1, such as methanol and methylamine. Due to their high phenotypic plasticity, these bacteria are able to colonize different habitats, such as soil, water, and sediment, and different host plants as both endophytes and epiphytes. In plant colonization, the frequency and distribution may be influenced by plant genotype or by interactions with other associated microorganisms, which may result in increasing plant fitness. In this review, different aspects of interactions with the host plant are discussed, including their capacity to fix nitrogen, nodule the host plant, produce cytokinins, auxin and enzymes involved in the induction of systemic resistance, such as pectinase and cellulase, and therefore plant growth promotion. In addition, bacteria belonging to this group can be used to reduce environmental contamination because they are able to degrade toxic compounds, tolerate high heavy metal concentrations, and increase plant tolerance to these compounds. Moreover, genome sequencing and omics approaches have revealed genes related to plant-bacteria interactions that may be important for developing strains able to promote plant growth and protection against phytopathogens.

Engineered monoculture and co-culture of methylotrophic yeast for de novo production of monacolin J and lovastatin from methanol.

Science.gov (United States)

Liu, Yiqi; Tu, Xiaohu; Xu, Qin; Bai, Chenxiao; Kong, Chuixing; Liu, Qi; Yu, Jiahui; Peng, Qiangqiang; Zhou, Xiangshan; Zhang, Yuanxing; Cai, Menghao

2018-01-01

As a promising one-carbon renewable substrate for industrial biotechnology, methanol has attracted much attention. However, engineering of microorganisms for industrial production of pharmaceuticals using a methanol substrate is still in infancy. In this study, the methylotrophic yeast Pichia pastoris was used to produce anti-hypercholesterolemia pharmaceuticals, lovastatin and its precursor monacolin J, from methanol. The biosynthetic pathways for monacolin J and lovastatin were first assembled and optimized in single strains using single copies of the relevant biosynthetic genes, and yields of 60.0mg/L monacolin J and 14.4mg/L lovastatin were obtained using methanol following pH controlled monoculture. To overcome limitations imposed by accumulation of intermediates and metabolic stress in monoculture, approaches using pathway splitting and co-culture were developed. Two pathway splitting strategies for monacolin J, and four for lovastatin were tested at different metabolic nodes. Biosynthesis of monacolin J and lovastatin was improved by 55% and 71%, respectively, when the upstream and downstream modules were separately accommodated in two different fluorescent strains, split at the metabolic node of dihydromonacolin L. However, pathway distribution at monacolin J blocked lovastatin biosynthesis in all designs, mainly due to its limited ability of crossing cellular membranes. Bioreactor fermentations were tested for the optimal co-culture strategies, and yields of 593.9mg/L monacolin J and 250.8mg/L lovastatin were achieved. This study provides an alternative method for production of monacolin J and lovastatin and reveals the potential of a methylotrophic yeast to produce complicated pharmaceuticals from methanol. Copyright © 2017 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

Methylobacterium populi sp. nov., a novel aerobic, pink-pigmented, facultatively methylotrophic, methane-utilizing bacterium isolated from poplar trees (Populus deltoides x nigra DN34).

Science.gov (United States)

Van Aken, Benoit; Peres, Caroline M; Doty, Sharon Lafferty; Yoon, Jong Moon; Schnoor, Jerald L

2004-07-01

A pink-pigmented, aerobic, facultatively methylotrophic bacterium, strain BJ001T, was isolated from internal poplar tissues (Populus deltoidesxnigra DN34) and identified as a member of the genus Methylobacterium. Phylogenetic analyses showed that strain BJ001T is related to Methylobacterium thiocyanatum, Methylobacterium extorquens, Methylobacterium zatmanii and Methylobacterium rhodesianum. However, strain BJ001T differed from these species in its carbon-source utilization pattern, particularly its use of methane as the sole source of carbon and energy, an ability that is shared with only one other member of the genus, Methylobacterium organophilum. In addition, strain BJ001T is the only member of the genus Methylobacterium to be described as an endophyte of poplar trees. On the basis of its physiological, genotypic and ecological properties, the isolate is proposed as a member of a novel species of the genus Methylobacterium, Methylobacterium populi sp. nov. (type strain, BJ001T=ATCC BAA-705T=NCIMB 13946T).

Relative importance of methylotrophic methanogenesis in sediments of the Western Mediterranean Sea

Science.gov (United States)

Zhuang, Guang-Chao; Heuer, Verena B.; Lazar, Cassandre S.; Goldhammer, Tobias; Wendt, Jenny; Samarkin, Vladimir A.; Elvert, Marcus; Teske, Andreas P.; Joye, Samantha B.; Hinrichs, Kai-Uwe

2018-03-01

Microbial production of methane is an important terminal metabolic process during organic matter degradation in marine sediments. It is generally acknowledged that hydrogenotrophic and acetoclastic methanogenesis constitute the dominant pathways of methane production; the importance of methanogenesis from methylated compounds remains poorly understood. We conducted various biogeochemical and molecular genetic analyses to characterize substrate availability, rates of methanogenesis, and methanogen community composition, and further evaluated the contribution of different substrates and pathways for methane production in deltaic surface and subsurface sediments of the Western Mediterranean Sea. Major substrates representing three methanogenic pathways, including H2, acetate, and methanol, trimethylamine (TMA), and dimethylsulfide (DMS), were detected in the pore waters and sediments, and exhibited variability over depth and between sites. In accompanying incubation experiments, methanogenesis rates from various 14C labeled substrates varied as well, suggesting that environmental factors, such as sulfate concentration and organic matter quality, could significantly influence the relative importance of individual pathway. In particular, methylotrophic and hydrogenotrophic methanogenesis contributed to the presence of micromolar methane concentrations in the sulfate reduction zone, with methanogenesis from methanol accounting for up to 98% of the total methane production in the topmost surface sediment. In the sulfate-depleted zone, hydrogenotrophic methanogenesis was the dominant methanogenic pathway (67-98%), and enhanced methane production from acetate was observed in organic-rich sediment (up to 31%). Methyl coenzyme M reductase gene (mcrA) analysis revealed that the composition of methanogenic communities was generally consistent with the distribution of methanogenic activity from different substrates. This study provides the first quantitative assessment of

[Engineering of a System for the Production of Mutant Human Alpha-Fetoprotein in the Methylotrophic Yeast Pichia pastoris].

Science.gov (United States)

Morozkina, E V; Vavilova, E A; Zatsepin, S S; Klyachko, E V; Yagudin, T A; Chulkin, A M; Dudich, I V; Semenkova, L N; Churilova, I V; Benevolenskii, S V

2016-01-01

A system for the production of mutant recombinant human alpha-fetoprotein (rhAFPO) lacking the glycosylation site has been engineered in the yeast Pichia pastoris. A strain of the methylotrophic yeast Pichia pastoris GS 115/pPICZ?A/rhAFP0, which produces unglycosylated rhAFPO and secretes it to the culture medium, has been constructed. Optimization and scale-up of the fermentation technology have resulted in an increase in the rhAFP0 yield to 20 mg/L. A scheme of isolation and purification of biologically active rhAFP0 has been developed. The synthesized protein has the antitumor activity, which is analogous to the activity of natural human embryonic alpha-fetoprotein.

Ethanol production by Kluyveromyces marxianus IMB3 during growth on straw-supplemented whiskey distillery spent wash at 45 C

Energy Technology Data Exchange (ETDEWEB)

Barron, N.; Mulholland, H.; Boyle, M.; McHale, A.P. [Biotechnology Research Group, School of Applied Biological and Chemical Sciences, University of Ulster, Coleraine, Co. Londonderry, BT52 1SA (United Kingdom)

1997-11-01

The thermotolerant, ethanol-producing yeast strain, Kluyveromyces marxianus IMB3 was grown on media consisting of straw-supplemented distillery spent wash from The Old Bushmill`s Distillery Co. Ltd., Bushmills, Co Antrim, Northern Ireland. Media were supplemented with cellulase activity and fermentations were carried out at 45 C. When pulverized straw was used as substrate in this system at concentrations of 2, 4 and 6% (w/v), ethanol concentrations increased to maxima of 1.45, 2.2 and 3 g/l, respectively. Based on straw containing a maximum of 40% cellulose, these ethanol concentrations accounted for 36, 27 and 24% of the maximum theoretical yield, respectively. When the straw was pre-treated with NaOH and used in the spent wash containing system at concentrations of 2, 4 and 6% (w/v) ethanol, concentrations increased to maxima of 3, 6.2 and 10.5 g/l, respectively and these accounted for 75, 76 and 86% of the maximum theoretical yield. When these results are compared with previously published data relating to the use of straw in laboratory-based media, they suggest that whiskey distillery spent wash may provide an adequate medium for supplementation with complex carbohydrate and subsequent ethanol production in simultaneous saccharification and fermentation processes. (orig.) With 2 figs., 17 refs.

Methylophaga natronica sp. nov., a new alkaliphilic and moderately halophilic, restricted-facultatively methylotrophic bacterium from soda lake of the Southern Transbaikal region.

Science.gov (United States)

Doronina, Nina; Darmaeva, Tsyregma; Trotsenko, Yuri

2003-09-01

A new, moderately haloalkaliphilic and restricted-facultatively methylotrophic bacterium (strain Bur2T) with the ribulose monophosphate pathway of carbon assimilation is described. The isolate, which utilizes methanol, methylamine and fructose, is an aerobic, Gram-negative, asporogenous, motile short rod multiplying by binary fission. It is auxotrophic for vitamin B12, and requires NaHCO3 or NaCl for growth in alkaline medium. Cellular fatty acids profile consists primarily of straight-chain saturated C16:0, unsaturated C16:1 and C18:1 acids. The major ubiquinone is Q-8. The dominant phospholipids are phosphatidylethanolamine and phosphatidylglycerol. Diphosphatidylglycerol is also present. Optimal growth conditions are 25-29 degrees C, pH 8.5-9.0 and 2-3% (w/v) NaCl. Cells accumulate ectoine and glutamate as the main osmoprotectants. The G + C content of the DNA is 45.0 mol%. Based on 16S rDNA sequence analysis and DNA-DNA relatedness (25-35%) with type strains of marine and soda lake methylobacteria belonging to the genus Methylophaga, the novel isolate was classified as a new species of this genus and named Methylophaga natronica (VKM B-2288T).

Organization of Genes Required for the Oxidation of Methanol to Formaldehyde in Three Type II Methylotrophs

Science.gov (United States)

Bastien, C.; Machlin, S.; Zhang, Y.; Donaldson, K.; Hanson, R. S.

1989-01-01

Restriction maps of genes required for the synthesis of active methanol dehydrogenase in Methylobacterium organophilum XX and Methylobacterium sp. strain AM1 have been completed and compared. In these two species of pink-pigmented, type II methylotrophs, 15 genes were identified that were required for the expression of methanol dehydrogenase activity. None of these genes were required for the synthesis of the prosthetic group of methanol dehydrogenase, pyrroloquinoline quinone. The structural gene required for the synthesis of cytochrome cL, an electron acceptor uniquely required for methanol dehydrogenase, and the genes encoding small basic peptides that copurified with methanol dehydrogenases were closely linked to the methanol dehydrogenase structural genes. A cloned 22-kilobase DNA insert from Methylsporovibrio methanica 81Z, an obligate type II methanotroph, complemented mutants that contained lesions in four genes closely linked to the methanol dehydrogenase structural genes. The methanol dehydrogenase and cytochrome cL structural genes were found to be transcribed independently in M. organophilum XX. Only two of the genes required for methanol dehydrogenase synthesis in this bacterium were found to be cotranscribed. PMID:16348074

Requirement of carbon dioxide for initial growth of facultative methylotroph, Acidomonas methanolica MB58.

Science.gov (United States)

Mitsui, Ryoji; Katayama, Hiroko; Tanaka, Mitsuo

2015-07-01

The facultative methylotrophic bacterium Acidomonas methanolica MB58 can utilize C1 compounds via the ribulose monophosphate pathway. A large gene cluster comprising three components related to C1 metabolism was found in the genome. From upstream, the first was an mxa cluster encoding proteins for oxidation of methanol to formaldehyde; the second was the rmp cluster encoding enzymes for formaldehyde fixation; and the third was the cbb gene cluster encoding proteins for carbon dioxide (CO2) fixation. Examination of CO2 requirements for growth of A. methanolica MB58 cells demonstrated that it did not grow on any carbon source under CO2-free conditions. Measurement of ribulose-1,5-bisphosphate carboxylase activity and RT-PCR analysis demonstrated enzymatic activity was detected in A. methanolica MB58 at growth phase, regardless of carbon sources. However, methanol dehydrogenase and 3-hexlose-6-phosphate synthase expression was regulated by methanol or formaldehyde; it were detected during growth and apparently differed from ribulose-1,5-bisphosphate carboxylase expression. These results suggested that A. methanolica MB58 may be initially dependent on autotrophic growth and that carbon assimilation was subsequently coupled with the ribulose monophosphate pathway at early- to mid-log phases during methylotrophic growth. Copyright © 2014 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

[Biotechnological potential of methylotrophic bacteria: a review of current status and future prospects].

Science.gov (United States)

Trotsenko, Iu A; Doronina, N V; Khmelenina, V N

2005-01-01

Major results of the authors' findings on the implementation of biotechnological potential of aerobic methylobacteria and methanotrophs for obtaining forage proteins, biopolymers (polybutyrate and polysaccharides), enzymes (oxidoreductases), and bioprotectors (ectoin), as well as for degrading toxic C1 and Cn compounds have been reviewed. Unique features of the structural and functional organization of the metabolism of extremophilic (tolerant) methylotrophs are discussed, with a view for their prospective use in various fields of modern biotechnology, including biocatalysis and nanotechnology.

Methylobacterium extorquens AM1 produces a novel type of acyl-homoserine lactone with a double unsaturated side chain under methylotrophic growth conditions.

Science.gov (United States)

Nieto Penalver, Carlos G; Morin, Danièle; Cantet, Franck; Saurel, Olivier; Milon, Alain; Vorholt, Julia A

2006-01-23

Acyl-homoserine lactones (acyl-HSLs) have emerged as important regulatory molecules for many gram-negative bacteria. We have found that Methylobacterium extorquens AM1, a member of the pink-pigmented facultative methylotrophs commonly present on plant surfaces, produces several acyl-HSLs depending upon the carbon source. A novel HSL was discovered with a double unsaturated carbon chain (N-(tetradecenoyl)) (C14:2) and characterized by MS and proton NMR. This long-chain acyl-HSL is synthesized by MlaI that also directs synthesis of C14:1-HSL. The Alphaproteobacterium also produces N-hexanoyl-HSL (C6-HSL) and N-octanoyl-HSL (C8-HSL) via MsaI.

[Processes of plant colonization by Methylobacterium strains and some bacterial properties ].

Science.gov (United States)

Romanovskaia, V A; Stoliar, S M; Malashenko, Iu R; Dodatko, T N

2001-01-01

The pink-pigmented facultative methylotrophic bacteria (PPFMB) of the genus Methylobacterium are indespensible inhabitants of the plant phyllosphere. Using maize Zea mays as a model, the ways of plant colonization by PPFMB and some properties of the latter that might be beneficial to plants were studied. A marked strain, Methylobacterium mesophilicum APR-8 (pULB113), was generated to facilitate the detection of the methylotrophic bacteria inoculated into the soil or applied to the maize leaves. Colonization of maize leaves by M. mesophilicum APR-8 (pULB113) occurred only after the bacteria were applied onto the leaf surface. In this case, the number of PPFMB cells on inoculated leaves increased with plant growth. During seed germination, no colonization of maize leaves with M. mesophilicum cells occurred immediately from the soil inoculated with the marked strain. Thus, under natural conditions, colonization of plant leaves with PPFMB seems to occur via soil particle transfer to the leaves by air. PPFMB monocultures were not antagonistic to phytopathogenic bacteria. However, mixed cultures of epiphytic bacteria containing Methylobacterium mesophilicum or M. extorquens did exhibit an antagonistic effect against the phytopathogenic bacteria studied (Xanthomonas camprestris, Pseudomonas syringae, Erwinia carotovora, Clavibacter michiganense, and Agrobacterium tumifaciens). Neither epiphytic and soil strains of Methylobacterium extorquens, M. organophillum, M. mesophilicum, and M. fujisawaense catalyzed ice nucleation. Hence, they cause no frost injury to plants. Thus, the results indicate that the strains of the genus Methylobacterium can protect plants against adverse environmental factors.

Peroxisomicine A1 (plant toxin-514) affects normal peroxisome assembly in the yeast Hansenula polymorpha

NARCIS (Netherlands)

Vargas-Zapata, Rigoberto; Torres-González, Vladimira; Sepúlveda-Saavedra, Julio; Piñeyro-López, Alfredo; Rechinger, Karl B.; Keizer-Gunnink, Ineke; Kiel, Jan A.K.W.; Veenhuis, Marten

Previously we demonstrated that peroxisomicine A1 (T-514), a plant toxin isolated from Karwinskia species, has a deteriorating effect on the integrity of peroxisomes of methylotrophic yeasts. Here we describe two strains of Hansenula polymorpha, affected in the normal utilization of methanol as sole

Sucrose-supplemented distillery spent wash as a medium for production of ethanol at 45 C by free and alginate-immobilized preparations of Kluyveromyces marxianus IMB3

Energy Technology Data Exchange (ETDEWEB)

Ferguson, P.; Mulholland, H.; Barron, N.; Brady, D.; McHale, A.P. [Biotechnology Research Group, School of Applied Biological and Chemical Sciences, University of Ulster (United Kingdom)

1998-04-01

Ethanol production by the thermotolerant, ethanol-producing yeast strain Kluyveromyces marxianus IMB3, was compared during growth on sucrose-supplemented laboratory-based media and distillery spent wash from the Old Bushmill`s Distillery Co., Ltd., Co. Antrim, Northern Ireland. Fermentations were carried out using preparations of the free and alginate-immobilized microorganism as inocula in media supplemented with 2 and 10% (w/v) sucrose. Maximum ethanol concentrations accounted for 75-99% of the maximum theoretical yield and in all cases maximum concentrations obtained using the spent wash were similar if not slightly higher than those obtained on the sucrose-supplemented yeast growth media. In addition, the highest concentrations of ethanol were produced by the alginate-immobilized biocatalyst on both types of media. Analysis of exhausted media in the spent wash-based systems demonstrated significant decreases in the total organic carbon content following fermentation. These results confirm our earlier suggestion that ethanol production based on this microorganism in a recycle system may provide a more cost-effective means of disposing of whiskey distillery spent wash. (orig.) With 1 tab., 8 refs.

Methylarcula marina gen. nov., sp. nov. and Methylarcula terricola sp. nov.: novel aerobic, moderately halophilic, facultatively methylotrophic bacteria from coastal saline environments.

Science.gov (United States)

Doronina, N V; Trotsenko, Y A; Tourova, T P

2000-09-01

A new genus, Methylarcula, with two new species, Methylarcula marina and Methylarcula terricola, are proposed for strains h1T and h37T of moderately halophilic facultatively methylotrophic bacteria isolated from the coastal saline habitats. These methylobacteria are aerobic, Gram-negative, asporogenous, non-motile, colourless rods that multiply by binary fission. Their cellular fatty acids profiles consist primarily of straight-chain unsaturated (C18:1; 70-80%), saturated (C18:0; 14-16%) and cyclopropane (C19:0; 5-6%) acids. The major ubiquinone is Q-10. The dominant phospholipids are phosphatidylethanolamine and phosphatidylcholine. Both strains could use methylamine, some sugars and organic acids as carbon and energy sources. They grew well under optimal conditions (29-35 degrees C, pH 7.5-8.5, 0.5-1.0 M NaCl) and accumulated intracellularly poly-beta-hydroxybutyrate and the compatible solute ectoine. The ectoine pool was found to increase upon increasing the external NaCl concentration and accounted for 18% of the dry cellular weight. Both strains oxidized methylamine by the N-methylglutamate (N-MG) pathway enzymes (gamma-glutamylmethylamide synthetase/lyase and N-MG synthetase/lyase) to formaldehyde and assimilated it via the icl- serine pathway. The DNA G+C content was 60-4 mol% for Methylarcula marina h1T and 57.1 mol% for Methylarcula terricola h37T. The DNA-DNA hybridization value between strains hl and h37 was 25-30%, although they had a low level of DNA relatedness (5-7%) with the type strains of the serine pathway methylobacteria belonging to the genera Methylobacterium, Aminobacter, Methylorhabdus and Methylopila. A comparative 16S rDNA sequence-based phylogenetic analysis placed the two species of Methylarcula into a separate branch of the alpha-3 subclass of the Proteobacteria. The type strains of the new species are Methylarcula marina h1T (= VKM B-2159T) and Methylarcula terricola h37T (= VKM B-2160T).

A search for neutrino and gamma ray burst temporal correlations with the IMB detector

International Nuclear Information System (INIS)

Becker-Szendy, R.; Bratton, C.B.; Breault, J.; Casper, D.; Dye, S.T.; Gajewski, W.; Goldhaber, M.; Haines, T.J.; Halverson, P.G.; Kielczewska, D.; Kropp, W.R.; Learned, J.G.; LoSecco, J.; Matsuno, S.; Matthews, J.; McGrath, G.; McGrew, C.; Miller, R.S.; Price, L.; Reines, F.; Schultz, J.; Sinclair, D.; Sobel, H.W.; Stone, J.L.; Sulak, L.R.; Svoboda, R.

1993-01-01

If Gamma Ray Bursts (GRBs) are associated with a stellar collapse-like phenomenon then it is resonable to expect neutrino production to occur at the source. We have performed a temporal correlation analysis with GRBs using the IMB low-energy neutrino dataset during 809 days of livetime between 1986 and 1990. No correlations were observed placing a 90%. C.L. limit of 0.046 ν interactions per GRB. The dependence of the GRB distances to neutrino yield using volume and shell distribution models is discussed. Lower limits are derived which exclude galactic stellar collapse-like models

Isolation and characterization of two new methanesulfonic acid-degrading bacterial isolates from a Portuguese soil sample.

Science.gov (United States)

De Marco, P; Murrell, J C; Bordalo, A A; Moradas-Ferreira, P

2000-02-01

Two novel bacterial strains that can utilize methanesulfonic acid as a source of carbon and energy were isolated from a soil sample collected in northern Portugal. Morphological, physiological, biochemical and molecular biological characterization of the two isolates indicate that strain P1 is a pink-pigmented facultative methylotroph belonging to the genus Methylobacterium, while strain P2 is a restricted methylotroph belonging to the genus Hyphomicrobium. Both strains are strictly aerobic, degrade methanesulfonate, and release small quantities of sulfite into the medium. Growth on methanesulfonate induces a specific polypeptide profile in each strain. This, together with the positive hybridization to a DNA probe that carries the msm genes of Methylosulfonomonas methylovora strain M2, strongly endorses the contention that a methanesulfonic acid monooxygenase related to that found in the previously known methanesulfonate-utilizing bacteria is present in strains P1 and P2. The isolation of bacteria containing conserved msm genes from diverse environments and geographical locations supports the hypothesis that a common enzyme may be globally responsible for the oxidation of methanesulfonate by natural methylotrophic communities.

Distribution of Pink-Pigmented Facultative Methylotrophs on Leaves of Vegetables

OpenAIRE

MIZUNO, Masayuki; YURIMOTO, Hiroya; YOSHIDA, Naoko; IGUCHI, Hiroyuki; SAKAI, Yasuyoshi

2012-01-01

The distribution of pink-pigmented facultative methylotrophs (PPFMs) on the leaves of various vegetables was studied. All kinds of vegetable leaves tested gave pink-pigmented colonies on agar plates containing methanol as sole carbon source. The numbers of PPFMs on the leaves, colony-forming units (CFU)/g of fresh leaves, differed among the plants, although they were planted and grown at the same farm. Commercial green perilla, Perilla frutescens viridis (Makino) Makino, gave the highest coun...

Genome information of Methylobacterium oryzae, a plant-probiotic methylotroph in the phyllosphere.

Science.gov (United States)

Kwak, Min-Jung; Jeong, Haeyoung; Madhaiyan, Munusamy; Lee, Yi; Sa, Tong-Min; Oh, Tae Kwang; Kim, Jihyun F

2014-01-01

Pink-pigmented facultative methylotrophs in the Rhizobiales are widespread in the environment, and many Methylobacterium species associated with plants produce plant growth-promoting substances. To gain insights into the life style at the phyllosphere and the genetic bases of plant growth promotion, we determined and analyzed the complete genome sequence of Methylobacterium oryzae CBMB20T, a strain isolated from rice stem. The genome consists of a 6.29-Mb chromosome and four plasmids, designated as pMOC1 to pMOC4. Among the 6,274 coding sequences in the chromosome, the bacterium has, besides most of the genes for the central metabolism, all of the essential genes for the assimilation and dissimilation of methanol that are either located in methylotrophy islands or dispersed. M. oryzae is equipped with several kinds of genes for adaptation to plant surfaces such as defense against UV radiation, oxidative stress, desiccation, or nutrient deficiency, as well as high proportion of genes related to motility and signaling. Moreover, it has an array of genes involved in metabolic pathways that may contribute to promotion of plant growth; they include auxin biosynthesis, cytokine biosynthesis, vitamin B12 biosynthesis, urea metabolism, biosorption of heavy metals or decrease of metal toxicity, pyrroloquinoline quinone biosynthesis, 1-aminocyclopropane-1-carboxylate deamination, phosphate solubilization, and thiosulfate oxidation. Through the genome analysis of M. oryzae, we provide information on the full gene complement of M. oryzae that resides in the aerial parts of plants and enhances plant growth. The plant-associated lifestyle of M. oryzae pertaining to methylotrophy and plant growth promotion, and its potential as a candidate for a bioinoculant targeted to the phyllosphere and focused on phytostimulation are illuminated.

[Methylophaga murata sp. nov.: a haloalkaliphilic aerobic methylotroph from deteriorating marble].

Science.gov (United States)

Doronina, N V; Li, Ts D; Ivanova, E G; Trotsenko, Iu A

2005-01-01

The haloalkaliphilic methylotrophic bacterium (strain Kr3) isolated from material scraped off the deteriorating marble of the Moscow Kremlin masonry has been found to be able to utilize methanol, methylamine, trimethylamine, and fructose as carbon and energy sources. Its cells are gram-negative motile rods multiplying by binary fission. Spores are not produced. The isolate is strictly aerobic and requires vitamin B12 and Na+ ions for growth. It is oxidase- and catalase-positive and reduces nitrates to nitrites. Growth occurs at temperatures between 0 and 42 degrees C (with the optimum temperatures being 20-32 degrees C), pH values between 6 and 11 (with the optimum at 8-9), and NaCl concentrations between 0.05 and 3 M (with the optimum at 0.5-1.5 M). The dominant cellular phospholipids are phosphatidylethanolamine, phosphatidylglycerol, and cardiolipin. The major cellular fatty acids are palmitic (C16:0), palmitoleic (C16:1), and octadecenoic (C18:1) acids. The major ubiquinone is Q8. The isolate accumulates ectoine and glutamate, as well as a certain amount of sucrose, to function as osmoprotectants and synthesizes an exopolysaccharide composed of carbohydrate and protein components. It is resistant to heating at 70 degrees C, freezing, and drying; utilizes methanol, with the resulting production of formic acid, which is responsible for the marble-degrading activity of the isolate; and implements the 2-keto-3-deoxy-6-phosphogluconate variant of the ribulose monophosphate pathway. The G+C content of its DNA is 44.6 mol%. Based on 16S rRNA gene sequencing and DNA-DNA homology levels (23-41%) with neutrophilic and alkaliphilic methylobacteria from the genus Methylophaga, the isolate has been identified as a new species, Methylophaga murata (VKM B-2303T = NCIMB 13993T).

Watermelon glyoxysomal malate dehydrogenase is sorted to peroxisomes of the methylotrophic yeast, Hansenula polymorpha

NARCIS (Netherlands)

Klei, I.J. van der; Faber, K.N.; Keizer-Gunnink, I.; Gietl, C.; Harder, W.; Veenhuis, M.

1993-01-01

We have studied the fate of the watermelon (Citrullus vulgaris Schrad.) glyoxysomal enzyme, malate dehydrogenase (gMDH), after synthesis in the methylotrophic yeast, Hansenula polymorpha. The gene encoding the precursor form of gMDH (pre-gMDH) was cloned in an H. polymorpha expression vector

Production of functionalized polyhydroxyalkanoates by genetically modified Methylobacterium extorquens strains

Directory of Open Access Journals (Sweden)

Miguez Carlos B

2010-09-01

Full Text Available Abstract Background Methylotrophic (methanol-utilizing bacteria offer great potential as cell factories in the production of numerous products from biomass-derived methanol. Bio-methanol is essentially a non-food substrate, an advantage over sugar-utilizing cell factories. Low-value products as well as fine chemicals and advanced materials are envisageable from methanol. For example, several methylotrophic bacteria, including Methylobacterium extorquens, can produce large quantities of the biodegradable polyester polyhydroxybutyric acid (PHB, the best known polyhydroxyalkanoate (PHA. With the purpose of producing second-generation PHAs with increased value, we have explored the feasibility of using M. extorquens for producing functionalized PHAs containing C-C double bonds, thus, making them amenable to future chemical/biochemical modifications for high value applications. Results Our proprietary M. extorquens ATCC 55366 was found unable to yield functionalized PHAs when fed methanol and selected unsaturated carboxylic acids as secondary substrates. However, cloning of either the phaC1 or the phaC2 gene from P. fluorescens GK13, using an inducible and regulated expression system based on cumate as inducer (the cumate switch, yielded recombinant M. extorquens strains capable of incorporating modest quantities of C-C double bonds into PHA, starting from either C6= and/or C8=. The two recombinant strains gave poor results with C11=. The strain containing the phaC2 gene was better at using C8= and at incorporating C-C double bonds into PHA. Solvent fractioning indicated that the produced polymers were PHA blends that consequently originated from independent actions of the native and the recombinant PHA synthases. Conclusions This work constitutes an example of metabolic engineering applied to the construction of a methanol-utilizing bacterium capable of producing functionalized PHAs containing C-C double bonds. In this regard, the PhaC2 synthase

The methylotrophic yeast Hansenula polymorpha contains an inducible import pathway for peroxisomal matrix proteins with an N-terminal targeting signal (PTS2 proteins)

NARCIS (Netherlands)

Faber, Klaas Nico; Haima, Pieter; Gietl, Christine; Harder, Willem; Ab, Geert; Veenhuis, Marten

1994-01-01

Two main types of peroxisomal targeting signals have been identified that reside either at the extreme C terminus (PTS1) or the N terminus (PTS2) of the protein. In the methylotrophic yeast Hansenula polymorpha the majority of peroxisomal matrix proteins are of the PTS1 type. Thus far, for H.

Development of the IMB Model and an Evidence-Based Diabetes Self-management Mobile Application.

Science.gov (United States)

Jeon, Eunjoo; Park, Hyeoun-Ae

2018-04-01

This study developed a diabetes self-management mobile application based on the information-motivation-behavioral skills (IMB) model, evidence extracted from clinical practice guidelines, and requirements identified through focus group interviews (FGIs) with diabetes patients. We developed a diabetes self-management (DSM) app in accordance with the following four stages of the system development life cycle. The functional and knowledge requirements of the users were extracted through FGIs with 19 diabetes patients. A system diagram, data models, a database, an algorithm, screens, and menus were designed. An Android app and server with an SSL protocol were developed. The DSM app algorithm and heuristics, as well as the usability of the DSM app were evaluated, and then the DSM app was modified based on heuristics and usability evaluation. A total of 11 requirement themes were identified through the FGIs. Sixteen functions and 49 knowledge rules were extracted. The system diagram consisted of a client part and server part, 78 data models, a database with 10 tables, an algorithm, and a menu structure with 6 main menus, and 40 user screens were developed. The DSM app was Android version 4.4 or higher for Bluetooth connectivity. The proficiency and efficiency scores of the algorithm were 90.96% and 92.39%, respectively. Fifteen issues were revealed through the heuristic evaluation, and the app was modified to address three of these issues. It was also modified to address five comments received by the researchers through the usability evaluation. The DSM app was developed based on behavioral change theory through IMB models. It was designed to be evidence-based, user-centered, and effective. It remains necessary to fully evaluate the effect of the DSM app on the DSM behavior changes of diabetes patients.

Genome information of Methylobacterium oryzae, a plant-probiotic methylotroph in the phyllosphere.

Directory of Open Access Journals (Sweden)

Min-Jung Kwak

Full Text Available Pink-pigmented facultative methylotrophs in the Rhizobiales are widespread in the environment, and many Methylobacterium species associated with plants produce plant growth-promoting substances. To gain insights into the life style at the phyllosphere and the genetic bases of plant growth promotion, we determined and analyzed the complete genome sequence of Methylobacterium oryzae CBMB20T, a strain isolated from rice stem. The genome consists of a 6.29-Mb chromosome and four plasmids, designated as pMOC1 to pMOC4. Among the 6,274 coding sequences in the chromosome, the bacterium has, besides most of the genes for the central metabolism, all of the essential genes for the assimilation and dissimilation of methanol that are either located in methylotrophy islands or dispersed. M. oryzae is equipped with several kinds of genes for adaptation to plant surfaces such as defense against UV radiation, oxidative stress, desiccation, or nutrient deficiency, as well as high proportion of genes related to motility and signaling. Moreover, it has an array of genes involved in metabolic pathways that may contribute to promotion of plant growth; they include auxin biosynthesis, cytokine biosynthesis, vitamin B12 biosynthesis, urea metabolism, biosorption of heavy metals or decrease of metal toxicity, pyrroloquinoline quinone biosynthesis, 1-aminocyclopropane-1-carboxylate deamination, phosphate solubilization, and thiosulfate oxidation. Through the genome analysis of M. oryzae, we provide information on the full gene complement of M. oryzae that resides in the aerial parts of plants and enhances plant growth. The plant-associated lifestyle of M. oryzae pertaining to methylotrophy and plant growth promotion, and its potential as a candidate for a bioinoculant targeted to the phyllosphere and focused on phytostimulation are illuminated.

Draft Genome Sequence of an Obligately Methylotrophic Methanogen, Methanococcoides methylutens, Isolated from Marine Sediment

KAUST Repository

Guan, Yue

2014-11-20

Methanococcoides methylutens, the type species of the genus Methanococcoides, is a slightly halophilic methanogenic archaeon with a methylotrophic metabolism. Here, we present the annotated draft genome sequence of M. methylutens, which comprises 2,508,511 bp with 2,482 coding sequences, 51 tRNA genes, and a G+C content of 42.5%.

Draft Genome Sequence of an Obligately Methylotrophic Methanogen, Methanococcoides methylutens, Isolated from Marine Sediment

KAUST Repository

Guan, Yue; Ngugi, David; Blom, J.; Ali, Shahjahan; Ferry, J. G.; Stingl, Ulrich

2014-01-01

Methanococcoides methylutens, the type species of the genus Methanococcoides, is a slightly halophilic methanogenic archaeon with a methylotrophic metabolism. Here, we present the annotated draft genome sequence of M. methylutens, which comprises 2,508,511 bp with 2,482 coding sequences, 51 tRNA genes, and a G+C content of 42.5%.

Direct measurement of carbon substrate oxidation and incorporation patterns in RuMP-type methylotrophs: chemostatic cultures of Methylomonas L3

International Nuclear Information System (INIS)

Chu, I.M.; Bussineau, C.M.; Papoutsakis, E.T.

1985-01-01

A technique using C-14 isotope tracers to probe the branching of carbon flow in methylotrophic bacteria has been devised and applied to continuous steady-state cultures. Methylomonas L3, a strain which utilizes the KDPG/TA variant of the ribulose monophosphate cycle for carbon fixation, was employed in the experimental studies. The actual in vivo rates of substrate-carbon incorporation into biomass, both direct and via CO 2 , and of the two carbon oxidation schemes were determined in three different steady-state cultures. The results show that the carbon substrate is oxidized predominantly via formate (the linear oxidation scheme), and that the cyclic scheme of oxidation is minimally, if at all, utilized. The carbon incorporation and oxidation patterns appear to vary considerably with the dilution rate and the inoculum history. The experimental accuracy of the new technique is discussed in detail

Deep Sequencing of Myxilla (Ectyomyxilla) methanophila, an Epibiotic Sponge on Cold-Seep Tubeworms, Reveals Methylotrophic, Thiotrophic, and Putative Hydrocarbon-Degrading Microbial Associations

KAUST Repository

Arellano, Shawn M.

2012-10-11

The encrusting sponge Myxilla (Ectyomyxilla) methanophila (Poecilosclerida: Myxillidae) is an epibiont on vestimentiferan tubeworms at hydrocarbon seeps on the upper Louisiana slope of the Gulf of Mexico. It has long been suggested that this sponge harbors methylotrophic bacteria due to its low δ13C value and high methanol dehydrogenase activity, yet the full community of microbial associations in M. methanophila remained uncharacterized. In this study, we sequenced 16S rRNA genes representing the microbial community in M. methanophila collected from two hydrocarbon-seep sites (GC234 and Bush Hill) using both Sanger sequencing and next-generation 454 pyrosequencing technologies. Additionally, we compared the microbial community in M. methanophila to that of the biofilm collected from the associated tubeworm. Our results revealed that the microbial diversity in the sponges from both sites was low but the community structure was largely similar, showing a high proportion of methylotrophic bacteria of the genus Methylohalomonas and polycyclic aromatic hydrocarbon (PAH)-degrading bacteria of the genera Cycloclasticus and Neptunomonas. Furthermore, the sponge microbial clone library revealed the dominance of thioautotrophic gammaproteobacterial symbionts in M. methanophila. In contrast, the biofilm communities on the tubeworms were more diverse and dominated by the chemoorganotrophic Moritella at GC234 and methylotrophic Methylomonas and Methylohalomonas at Bush Hill. Overall, our study provides evidence to support previous suggestion that M. methanophila harbors methylotrophic symbionts and also reveals the association of PAH-degrading and thioautotrophic microbes in the sponge. © 2012 Springer Science+Business Media New York.

Deep sequencing of Myxilla (Ectyomyxilla) methanophila, an epibiotic sponge on cold-seep tubeworms, reveals methylotrophic, thiotrophic, and putative hydrocarbon-degrading microbial associations.

Science.gov (United States)

Arellano, Shawn M; Lee, On On; Lafi, Feras F; Yang, Jiangke; Wang, Yong; Young, Craig M; Qian, Pei-Yuan

2013-02-01

The encrusting sponge Myxilla (Ectyomyxilla) methanophila (Poecilosclerida: Myxillidae) is an epibiont on vestimentiferan tubeworms at hydrocarbon seeps on the upper Louisiana slope of the Gulf of Mexico. It has long been suggested that this sponge harbors methylotrophic bacteria due to its low δ(13)C value and high methanol dehydrogenase activity, yet the full community of microbial associations in M. methanophila remained uncharacterized. In this study, we sequenced 16S rRNA genes representing the microbial community in M. methanophila collected from two hydrocarbon-seep sites (GC234 and Bush Hill) using both Sanger sequencing and next-generation 454 pyrosequencing technologies. Additionally, we compared the microbial community in M. methanophila to that of the biofilm collected from the associated tubeworm. Our results revealed that the microbial diversity in the sponges from both sites was low but the community structure was largely similar, showing a high proportion of methylotrophic bacteria of the genus Methylohalomonas and polycyclic aromatic hydrocarbon (PAH)-degrading bacteria of the genera Cycloclasticus and Neptunomonas. Furthermore, the sponge microbial clone library revealed the dominance of thioautotrophic gammaproteobacterial symbionts in M. methanophila. In contrast, the biofilm communities on the tubeworms were more diverse and dominated by the chemoorganotrophic Moritella at GC234 and methylotrophic Methylomonas and Methylohalomonas at Bush Hill. Overall, our study provides evidence to support previous suggestion that M. methanophila harbors methylotrophic symbionts and also reveals the association of PAH-degrading and thioautotrophic microbes in the sponge.

Overexpression of the genes PDC1 and ADH1 activates glycerol conversion to ethanol in the thermotolerant yeast Ogataea (Hansenula) polymorpha.

Science.gov (United States)

Kata, Iwona; Semkiv, Marta V; Ruchala, Justyna; Dmytruk, Kostyantyn V; Sibirny, Andriy A

2016-08-01

Conversion of byproduct from biodiesel production glycerol to high-value compounds is of great importance. Ethanol is considered a promising product of glycerol bioconversion. The methylotrophic thermotolerant yeast Ogataea (Hansenula) polymorpha is of great interest for this purpose as the glycerol byproduct contains methanol and heavy metals as contaminants, and this yeast utilizes methanol and is relatively resistant to heavy metals. Besides, O. polymorpha shows robust growth on glycerol and produces ethanol from various carbon sources. The thermotolerance of this yeast is an additional advantage, allowing increased fermentation temperature to 45-48 °C, leading to increased rate of the fermentation process and a fall in the cost of distillation. The wild-type strain of O. polymorpha produces insignificant amounts of ethanol from glycerol (0.8 g/l). Overexpression of PDC1 coding for pyruvate decarboxylase enhanced ethanol production up to 3.1 g/l, whereas simultaneous overexpression of PDC1 and ADH1 (coding for alcohol dehydrogenase) led to further increase in ethanol production from glycerol. Moreover, the increased temperature of fermentation up to 45 °C stimulated the production of ethanol from glycerol used as the only carbon source up to 5.0 g/l, which exceeds the data obtained by methylotrophic yeast strains reported so far. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Willingness to Use Pre-Exposure Prophylaxis (PrEP): An Empirical Test of the Information-Motivation-Behavioral Skills (IMB) Model among High-Risk Drug Users in Treatment.

Science.gov (United States)

Shrestha, Roman; Altice, Frederick L; Huedo-Medina, Tania B; Karki, Pramila; Copenhaver, Michael

2017-05-01

Evidence from recent pre-exposure prophylaxis (PrEP) trials has demonstrated its safety and efficacy in significantly reducing the risk of HIV acquisition for those who are at considerable risk of acquiring HIV infection. With a rapid increase in the amount of research on the efficacy of PrEP for HIV prevention, complementary research on the willingness to use PrEP has grown, especially among MSM, but limited research has been focused among people who use drugs (PWUD). As part of the formative process, we utilized the information-motivation-behavioral skills (IMB) model of health behavior change to characterize and guide intervention development for promoting willingness to use PrEP among high-risk PWUD. The analysis included 400 HIV-negative high-risk PWUD enrolled in a community-based methadone maintenance treatment who reported drug- and/or sex-related HIV risk behaviors in the past 6-months. Analyses revealed support for the IMB model as PrEP-related behavioral skills were found to mediate the influence of PrEP-related information and motivation on willingness to use PrEP. The results provide evidence as to the utility of the IMB model to increase willingness to use PrEP among high-risk PWUD. It therefore makes an important contribution to our understanding of the applicability of theoretically-grounded models of willingness to use PrEP among high-risk PWUD, who are one of the key risk populations who could benefit from the use of PrEP.

Genetic and metabolic diversity of pink-pigmented facultative methylotrophs in phyllosphere of tropical plants

OpenAIRE

Balachandar, D.; Raja, P.; Sundaram, SP.

2008-01-01

Diversity of Pink-Pigmented Facultative Methylotrophs (PPFMs) in phyllosphere of cotton, maize and sunflower was determined based on differential carbon-substrate utilization profile and Random Amplified Polymorphic DNA data. Results indicate that six diversified groups of PPFMs are found in these crops. Sunflower and maize phyllosphere harbor four different groups of methylobacteria while cotton has only two groups.

Genetic and metabolic diversity of pink-pigmented facultative methylotrophs in phyllosphere of tropical plants.

Science.gov (United States)

Balachandar, D; Raja, P; Sundaram, Sp

2008-01-01

Diversity of Pink-Pigmented Facultative Methylotrophs (PPFMs) in phyllosphere of cotton, maize and sunflower was determined based on differential carbon-substrate utilization profile and Random Amplified Polymorphic DNA data. Results indicate that six diversified groups of PPFMs are found in these crops. Sunflower and maize phyllosphere harbor four different groups of methylobacteria while cotton has only two groups.

Methylobacterium genome sequences: a reference blueprint to investigate microbial metabolism of C1 compounds from natural and industrial sources.

Directory of Open Access Journals (Sweden)

Stéphane Vuilleumier

Full Text Available Methylotrophy describes the ability of organisms to grow on reduced organic compounds without carbon-carbon bonds. The genomes of two pink-pigmented facultative methylotrophic bacteria of the Alpha-proteobacterial genus Methylobacterium, the reference species Methylobacterium extorquens strain AM1 and the dichloromethane-degrading strain DM4, were compared.The 6.88 Mb genome of strain AM1 comprises a 5.51 Mb chromosome, a 1.26 Mb megaplasmid and three plasmids, while the 6.12 Mb genome of strain DM4 features a 5.94 Mb chromosome and two plasmids. The chromosomes are highly syntenic and share a large majority of genes, while plasmids are mostly strain-specific, with the exception of a 130 kb region of the strain AM1 megaplasmid which is syntenic to a chromosomal region of strain DM4. Both genomes contain large sets of insertion elements, many of them strain-specific, suggesting an important potential for genomic plasticity. Most of the genomic determinants associated with methylotrophy are nearly identical, with two exceptions that illustrate the metabolic and genomic versatility of Methylobacterium. A 126 kb dichloromethane utilization (dcm gene cluster is essential for the ability of strain DM4 to use DCM as the sole carbon and energy source for growth and is unique to strain DM4. The methylamine utilization (mau gene cluster is only found in strain AM1, indicating that strain DM4 employs an alternative system for growth with methylamine. The dcm and mau clusters represent two of the chromosomal genomic islands (AM1: 28; DM4: 17 that were defined. The mau cluster is flanked by mobile elements, but the dcm cluster disrupts a gene annotated as chelatase and for which we propose the name "island integration determinant" (iid.These two genome sequences provide a platform for intra- and interspecies genomic comparisons in the genus Methylobacterium, and for investigations of the adaptive mechanisms which allow bacterial lineages to acquire

Methylobacterium genome sequences: a reference blueprint to investigate microbial metabolism of C1 compounds from natural and industrial sources.

Science.gov (United States)

Vuilleumier, Stéphane; Chistoserdova, Ludmila; Lee, Ming-Chun; Bringel, Françoise; Lajus, Aurélie; Zhou, Yang; Gourion, Benjamin; Barbe, Valérie; Chang, Jean; Cruveiller, Stéphane; Dossat, Carole; Gillett, Will; Gruffaz, Christelle; Haugen, Eric; Hourcade, Edith; Levy, Ruth; Mangenot, Sophie; Muller, Emilie; Nadalig, Thierry; Pagni, Marco; Penny, Christian; Peyraud, Rémi; Robinson, David G; Roche, David; Rouy, Zoé; Saenampechek, Channakhone; Salvignol, Grégory; Vallenet, David; Wu, Zaining; Marx, Christopher J; Vorholt, Julia A; Olson, Maynard V; Kaul, Rajinder; Weissenbach, Jean; Médigue, Claudine; Lidstrom, Mary E

2009-01-01

Methylotrophy describes the ability of organisms to grow on reduced organic compounds without carbon-carbon bonds. The genomes of two pink-pigmented facultative methylotrophic bacteria of the Alpha-proteobacterial genus Methylobacterium, the reference species Methylobacterium extorquens strain AM1 and the dichloromethane-degrading strain DM4, were compared. The 6.88 Mb genome of strain AM1 comprises a 5.51 Mb chromosome, a 1.26 Mb megaplasmid and three plasmids, while the 6.12 Mb genome of strain DM4 features a 5.94 Mb chromosome and two plasmids. The chromosomes are highly syntenic and share a large majority of genes, while plasmids are mostly strain-specific, with the exception of a 130 kb region of the strain AM1 megaplasmid which is syntenic to a chromosomal region of strain DM4. Both genomes contain large sets of insertion elements, many of them strain-specific, suggesting an important potential for genomic plasticity. Most of the genomic determinants associated with methylotrophy are nearly identical, with two exceptions that illustrate the metabolic and genomic versatility of Methylobacterium. A 126 kb dichloromethane utilization (dcm) gene cluster is essential for the ability of strain DM4 to use DCM as the sole carbon and energy source for growth and is unique to strain DM4. The methylamine utilization (mau) gene cluster is only found in strain AM1, indicating that strain DM4 employs an alternative system for growth with methylamine. The dcm and mau clusters represent two of the chromosomal genomic islands (AM1: 28; DM4: 17) that were defined. The mau cluster is flanked by mobile elements, but the dcm cluster disrupts a gene annotated as chelatase and for which we propose the name "island integration determinant" (iid). These two genome sequences provide a platform for intra- and interspecies genomic comparisons in the genus Methylobacterium, and for investigations of the adaptive mechanisms which allow bacterial lineages to acquire methylotrophic

Complete Genome Sequence of the Facultative Methylotroph Methylobacterium extorquens TK 0001 Isolated from Soil in Poland.

Science.gov (United States)

Belkhelfa, Sophia; Labadie, Karine; Cruaud, Corinne; Aury, Jean-Marc; Roche, David; Bouzon, Madeleine; Salanoubat, Marcel; Döring, Volker

2018-02-22

Methylobacterium extorquens TK 0001 (DSM 1337, ATCC 43645) is an aerobic pink-pigmented facultative methylotrophic alphaproteobacterium isolated from soil in Poland. Here, we report the whole-genome sequence and annotation of this organism, which consists of a single 5.71-Mb chromosome. Copyright © 2018 Belkhelfa et al.

Distribution of pink-pigmented facultative methylotrophs on leaves of vegetables.

Science.gov (United States)

Mizuno, Masayuki; Yurimoto, Hiroya; Yoshida, Naoko; Iguchi, Hiroyuki; Sakai, Yasuyoshi

2012-01-01

The distribution of pink-pigmented facultative methylotrophs (PPFMs) on the leaves of various vegetables was studied. All kinds of vegetable leaves tested gave pink-pigmented colonies on agar plates containing methanol as sole carbon source. The numbers of PPFMs on the leaves, colony-forming units (CFU)/g of fresh leaves, differed among the plants, although they were planted and grown at the same farm. Commercial green perilla, Perilla frutescens viridis (Makino) Makino, gave the highest counts of PPFMs (2.0-4.1×10(7) CFU/g) of all the commercial vegetable leaves tested, amounting to 15% of total microbes on the leaves. The PPFMs isolated from seeds of two varieties of perilla, the red and green varieties, exhibited high sequence similarity as to the 16S rRNA gene to two different Methylobacterium species, M. fujisawaense DSM5686(T) and M. radiotolerans JCM2831(T) respectively, suggesting that there is specific interaction between perilla and the PPFMs.

The Abundance of Pink-Pigmented Facultative Methylotrophs in the Root Zone of Plant Species in Invaded Coastal Sage Scrub Habitat

OpenAIRE

Irvine, Irina C.; Brigham, Christy A.; Suding, Katharine N.; Martiny, Jennifer H.

2012-01-01

Pink-pigmented facultative methylotrophic bacteria (PPFMs) are associated with the roots, leaves and seeds of most terrestrial plants and utilize volatile C(1) compounds such as methanol generated by growing plants during cell division. PPFMs have been well studied in agricultural systems due to their importance in crop seed germination, yield, pathogen resistance and drought stress tolerance. In contrast, little is known about the PPFM abundance and diversity in natural ecosystems, let alone...

Culturable Facultative Methylotrophic Bacteria from the Cactus Neobuxbaumia macrocephala Possess the Locus xoxF and Consume Methanol in the Presence of Ce3+ and Ca2.

Science.gov (United States)

Del Rocío Bustillos-Cristales, María; Corona-Gutierrez, Ivan; Castañeda-Lucio, Miguel; Águila-Zempoaltécatl, Carolina; Seynos-García, Eduardo; Hernández-Lucas, Ismael; Muñoz-Rojas, Jesús; Medina-Aparicio, Liliana; Fuentes-Ramírez, Luis Ernesto

2017-09-27

Methanol-consuming culturable bacteria were isolated from the plant surface, rhizosphere, and inside the stem of Neobuxbaumia macrocephala. All 38 isolates were facultative methylotrophic microorganisms. Their classification included the Classes Actinobacteria, Sphingobacteriia, Alpha-, Beta-, and Gammaproteobacteria. The deduced amino acid sequences of methanol dehydrogenase obtained by PCR belonging to Actinobacteria, Alpha-, Beta-, and Gammaproteobacteria showed high similarity to rare-earth element (REE)-dependent XoxF methanol dehydrogenases, particularly the group XoxF5. The sequences included Asp 301 , the REE-coordinating amino acid, present in all known XoxF dehydrogenases and absent in MxaF methanol dehydrogenases. The quantity of the isolates showed positive hybridization with a xoxF probe, but not with a mxaF probe. Isolates of all taxonomic groups showed methylotrophic growth in the presence of Ce 3+ or Ca 2+ . The presence of xoxF-like sequences in methylotrophic bacteria from N. macrocephala and its potential relationship with their adaptability to xerophytic plants are discussed.

Methods for efficient high-throughput screening of protein expression in recombinant Pichia pastoris strains.

Science.gov (United States)

Camattari, Andrea; Weinhandl, Katrin; Gudiminchi, Rama K

2014-01-01

The methylotrophic yeast Pichia pastoris is becoming one of the favorite industrial workhorses for protein expression. Due to the widespread use of integration vectors, which generates significant clonal variability, screening methods allowing assaying hundreds of individual clones are of particular importance. Here we describe methods to detect and analyze protein expression, developed in a 96-well format for high-throughput screening of recombinant P. pastoris strains. The chapter covers essentially three common scenarios: (1) an enzymatic assay for proteins expressed in the cell cytoplasm, requiring cell lysis; (2) a whole-cell assay for a fungal cytochrome P450; and (3) a nonenzymatic assay for detection and quantification of tagged protein secreted into the supernatant.

Influence of plant species and environmental conditions on epiphytic and endophytic pink-pigmented facultative methylotrophic bacterial populations associated with field-grown rice cultivars.

Science.gov (United States)

Madhaiyan, Munusamy; Poonguzhali, Selvaraj; Sa, Tongmin

2007-10-01

The total methylotrophic population associated with rice plants from different cultivars was enumerated at three different stages: vegetative, flowering, and harvesting. The bacterial population in the leaf, rhizosphere soil, endophytic in the stem and roots, and epiphytic in the florets and grains were determined from four rice cultivars, Il-mi, Nam-pyeoung, O-dae, and Dong-jin, sampled from three different field sites. The methylotrophic bacteria isolated on AMS media containing 0.5% methanol as the sole carbon source uniformly showed three distinct morphologies, which were recorded as separate groups and their distribution among the various samples was determined using the ecophysiological index. The growth stage at the time of sampling had a more significant effect on the methylotrophic population and their distribution than the field site or cultivar. A similar effect was also observed for the PPFMs, where their population in different plant parts increased from V10 to R4 and then decreased towards stage R9. A canonical discriminant analysis of the PPFM population from different parts of rice showed clear variations among the cultivars, sampled sites, and growth stages, although the variations were more prominent among the growth stages.

Degradation of formaldehyde at high concentrations by phenol-adapted Ralstonia eutropha closely related to pink-pigmented facultative methylotrophs.

Science.gov (United States)

Habibi, Alireza; Vahabzadeh, Farzaneh

2013-01-01

The ability of the phenol-adapted Ralstonia eutropha to utilize formaldehyde (FD) as the sole source of carbon and energy was studied. Adaptation to FD was accomplished by substituting FD for glucose in a stepwise manner. The bacterium in the liquid test culture could tolerate concentrations of FD up to 900 mg L(-1). Degradation of FD was complete in 528 h at 30°C with shaking at 150 rpm (r = 1.67 mg L(-1) h(-1)), q = 0.035 g(FD) g(cell) (-1) h(-1). Substrate inhibition kinetics (Haldane and Luong equations) are used to describe the experimental data. At non-inhibitory concentrations of FD, the Monod equation was used. According to the Luong model, the values of the maximum specific growth rate (μ(max)), half-saturation coefficient (k(S)), the maximum allowable formaldehyde concentration (S(m)), and the shape factor (n) were 0.117 h(-1), 47.6 mg L(-1), 900 mg L(-1), and 2.2, respectively. The growth response of the test bacterium to consecutive FD feedings was examined, and the FD-adapted R. eutropha cells were able to degrade 1000 mg L(-1) FD in 150 h through 4 cycles of FD feeds. During FD degradation, formic acid metabolite was formed. Assimilation of FD, methanol, formic acid, and oxalate by the test bacterium was accompanied by the formation of a pink pigment. The carotenoid nature of the cellular pigment has been confirmed and the test bacterium appeared to be closely related to pink-pigmented facultative methylotrophs (PPFM). The extent of harm to soil exposed to biotreated wastewaters containing FD may be moderated due to the association between methylotrophic/oxalotrophic bacteria and plants.

Isolation and characterization of new strains of methanogens from cold terrestrial habitats.

Science.gov (United States)

Simankova, Maria V; Kotsyurbenko, Oleg R; Lueders, Tillmann; Nozhevnikova, Alla N; Wagner, Bianca; Conrad, Ralf; Friedrich, Michael W

2003-06-01

Five strains of methanogenic archaea (MT, MS, MM, MSP, ZB) were isolated from permanently and periodically cold terrestrial habitats. Physiological and morphological studies, as well as phylogenetic analyses of the new isolates were performed. Based on sequences of the 16S rRNA and methyl-coenzyme M reductase a-subunit (mcrA) genes all new isolates are closely related to known mesophilic and psychrotolerant methanogens. Both, phylogenetic analyses and phenotypic properties allow to classify strains MT, MS, and MM as members of the genus Methanosarcina. Strain MT is a new ecotype of Methanosarcina mazei, whereas strains MM and MS are very similar to each other and can be assigned to the recently described psychrotolerant species Methanosarcina lacustris. The hydrogenotrophic strain MSP is a new ecotype of the genus Methanocorpusculum. The obligately methylotrophic strain ZB is closely related to Methanomethylovorans hollandica and can be classified as new ecotype of this species. All new isolates, including the strains from permanently cold environments, are not true psychrophiles according to their growth temperature characteristics. In spite of the ability of all isolates to grow at temperatures as low as 1-5 degrees C, all of them have their growth optima in the range of moderate temperatures (25-35 degrees C). Thus, they can be regarded as psychrotolerant organisms. Psychrotolerant methanogens are thought to play an important role in methane production in both, habitats under seasonal temperature variations or from permanently cold areas.

Dominant colonization and inheritance of Methylobacterium sp. strain OR01 on perilla plants.

Science.gov (United States)

Mizuno, Masayuki; Yurimoto, Hiroya; Iguchi, Hiroyuki; Tani, Akio; Sakai, Yasuyoshi

2013-01-01

Pink-pigmented facultative methylotrophs (PPFMs) are major inhabitants of the phyllosphere. In a preceding study, we found that perilla plants harbor a dominant population of PPFMs on their leaves and seeds, and that the closest relative of PPFMs (Methylobacterium sp. strain OR01 as representative strain) isolated from red perilla seeds was M. fujisawaense DSM5686(T). In the present study, the specific interaction between red perilla and Methylobacterium species was investigated. All the PPFMs isolated from red perilla seeds harvested in the Ohara area of Kyoto, Japan in 2009, 2010, and 2011 and the PPFMs isolated from red perilla leaves planted at four geographically different places in Japan had 16S rRNA sequences identical to that of strain OR01. Direct transmission of PPFMs from seeds to leaves and the competitiveness of strain OR01 were confirmed. This report is the first step toward understanding the species-level specificity of the interaction between perilla plants and Methylobacterium species.

High-frequency transformation of a methylotrophic yeast, Candida boidinii, with autonomously replicating plasmids which are also functional in Saccharomyces cerevisiae.

OpenAIRE

Sakai, Y; Goh, T K; Tani, Y

1993-01-01

We have developed a transformation system which uses autonomous replicating plasmids for a methylotrophic yeast, Candida boidinii. Two autonomous replication sequences, CARS1 and CARS2, were newly cloned from the genome of C. boidinii. Plasmids having both a CARS fragment and the C. boidinii URA3 gene transformed C. boidinii ura3 cells to Ura+ phenotype at frequencies of up to 10(4) CFU/micrograms of DNA. From Southern blot analysis, CARS plasmids seemed to exist in polymeric forms as well as...

XoxF Is Required for Expression of Methanol Dehydrogenase in Methylobacterium extorquens AM1 ▿

Science.gov (United States)

Skovran, Elizabeth; Palmer, Alexander D.; Rountree, Austin M.; Good, Nathan M.; Lidstrom, Mary E.

2011-01-01

In Gram-negative methylotrophic bacteria, the first step in methylotrophic growth is the oxidation of methanol to formaldehyde in the periplasm by methanol dehydrogenase. In most organisms studied to date, this enzyme consists of the MxaF and MxaI proteins, which make up the large and small subunits of this heterotetrameric enzyme. The Methylobacterium extorquens AM1 genome contains two homologs of MxaF, XoxF1 and XoxF2, which are ∼50% identical to MxaF and ∼90% identical to each other. It was previously reported that xoxF is not required for methanol growth in M. extorquens AM1, but here we show that when both xoxF homologs are absent, strains are unable to grow in methanol medium and lack methanol dehydrogenase activity. We demonstrate that these defects result from the loss of gene expression from the mxa promoter and suggest that XoxF is part of a complex regulatory cascade involving the 2-component systems MxcQE and MxbDM, which are required for the expression of the methanol dehydrogenase genes. PMID:21873495

Mutagenesis and reparation processes in the methylotrophic bacterium Pseudomonas methanolica after UV irradiation

International Nuclear Information System (INIS)

Naumov, G.N.; Bokhan, I.K.; Multykh, I.G.

1986-01-01

High resistance of cells of methylotrophic bacterium Pseudomonas methanolica to bactericidal and mutagenous effects of ultraviolet irradiation is shown as well as activity of reparation processes after UV irradiation. The presence of low photoreactivating activity in P. methanolica is shown as well. Observed recovery in innutritious medium and decrease of irradiated cells survival rates under effect of reparation inhibitors (coffeine and acriflavine) testify to activity of excision reparation and, perhaps, recombination branch of postreplicative reparation. No manifestation of inducible reparation system is discovered. It is concluded that increased resistance of P. methanolica cells to bactericidal and mutagenous effects of short-wave ultraviolet radiation is related to activity of exact reparation systems

Screening and characterization of alkaline protease produced by a pink pigmented facultative methylotrophic (PPFM) strain, MSF 46

OpenAIRE

Jayashree, Shanmugam; Annapurna, Balumuri; Jayakumar, Renganathan; Sa, Tongmin; Seshadri, Sundaram

2014-01-01

Among the various bacterial isolates, the strain MSF 46 isolated from thorn forest soil samples, Tamil Nadu, India, was screened and characterized for its proteolytic activity. While the 16S rRNA sequencing and biochemical characterization revealed that the strain closely resembles Methylobacterium sp., methylotrophy of the strain was confirmed by the sequence homology of mxaF gene with other relative Methylobacterium sp. The alkaline protease was purified to homogeneity using DEAE cellulose ...

Phenotypic and genetic diversity of chlorine-resistant Methylobacterium strains isolated from various environments.

Science.gov (United States)

Hiraishi, A; Furuhata, K; Matsumoto, A; Koike, K A; Fukuyama, M; Tabuchi, K

1995-01-01

Strains of pink-pigmented facultative methylotrophs which were isolated previously from various environments and assigned tentatively to the genus Methylobacterium were characterized in comparison with authentic strains of previously known species of this genus. Most of the isolates derived from chlorinated water supplies exhibited resistance to chlorine, whereas 29 to 40% of the isolates from air, natural aquatic environments, and clinical materials were chlorine resistant. None of the tested authentic strains of Methylobacterium species obtained from culture collections exhibited chlorine resistance. Numerical analysis of phenotypic profiles showed that the test organisms tested were separated from each other except M. organophilum and M. rhodesianum. The chlorine-resistant isolates were randomly distributed among all clusters. The 16S ribosomal DNA (rDNA) sequence-based phylogenetic analyses showed that representatives of the isolates together with known Methylobacterium species formed a line of descent distinct from that of members of related genera in the alpha-2 subclass of the Proteobacteria and were divided into three subclusters within the Methylobacterium group. These results demonstrate that there is phenotypic and genetic diversity among chlorine-resistant Methylobacterium strains within the genus. PMID:7793931

Phenotypic and genetic diversity of chlorine-resistant Methylobacterium strains isolated from various environments.

Science.gov (United States)

Hiraishi, A; Furuhata, K; Matsumoto, A; Koike, K A; Fukuyama, M; Tabuchi, K

1995-06-01

Strains of pink-pigmented facultative methylotrophs which were isolated previously from various environments and assigned tentatively to the genus Methylobacterium were characterized in comparison with authentic strains of previously known species of this genus. Most of the isolates derived from chlorinated water supplies exhibited resistance to chlorine, whereas 29 to 40% of the isolates from air, natural aquatic environments, and clinical materials were chlorine resistant. None of the tested authentic strains of Methylobacterium species obtained from culture collections exhibited chlorine resistance. Numerical analysis of phenotypic profiles showed that the test organisms tested were separated from each other except M. organophilum and M. rhodesianum. The chlorine-resistant isolates were randomly distributed among all clusters. The 16S ribosomal DNA (rDNA) sequence-based phylogenetic analyses showed that representatives of the isolates together with known Methylobacterium species formed a line of descent distinct from that of members of related genera in the alpha-2 subclass of the Proteobacteria and were divided into three subclusters within the Methylobacterium group. These results demonstrate that there is phenotypic and genetic diversity among chlorine-resistant Methylobacterium strains within the genus.

Heterologous expression of a deuterated membrane-integrated receptor and partial deuteration in methylotrophic yeasts

International Nuclear Information System (INIS)

Massou, S.; Puech, V.; Talmont, F.; Demange, P.; Lindley, N.D.; Tropis, M.; Milon, A.

1999-01-01

Methylotrophic yeast has previously been shown to be an excellent system for the cost-effective production of perdeuterated biomass and for the heterologous expression of membrane receptors. A protocol for the expression of 85% deuterated, functional human μ-opiate receptor was established. For partially deuterated biomass, deuteration level and distribution were determined for fatty acids, amino acids and carbohydrates. It was shown that prior to biosynthesis of lipids and amino acids (and of carbohydrates, to a lower extent), exchange occurs between water and methanol hydrogen atoms, so that 80%-90% randomly deuterated biomass and over-expressed proteins may be obtained using only deuterated water

Genetic Characterization of the Carotenoid Biosynthetic Pathway in Methylobacterium extorquens AM1 and Isolation of a Colorless Mutant

Science.gov (United States)

Van Dien, Stephen J.; Marx, Christopher J.; O'Brien, Brooke N.; Lidstrom, Mary E.

2003-01-01

Genomic searches were used to reconstruct the putative carotenoid biosynthesis pathway in the pink-pigmented facultative methylotroph Methylobacterium extorquens AM1. Four genes for putative phytoene desaturases were identified. A colorless mutant was obtained by transposon mutagenesis, and the insertion was shown to be in one of the putative phytoene desaturase genes. Mutations in the other three did not affect color. The tetracycline marker was removed from the original transposon mutant, resulting in a pigment-free strain with wild-type growth properties useful as a tool for future experiments. PMID:14660416

Genetic characterization of the carotenoid biosynthetic pathway in Methylobacterium extorquens AM1 and isolation of a colorless mutant.

Science.gov (United States)

Van Dien, Stephen J; Marx, Christopher J; O'Brien, Brooke N; Lidstrom, Mary E

2003-12-01

Genomic searches were used to reconstruct the putative carotenoid biosynthesis pathway in the pink-pigmented facultative methylotroph Methylobacterium extorquens AM1. Four genes for putative phytoene desaturases were identified. A colorless mutant was obtained by transposon mutagenesis, and the insertion was shown to be in one of the putative phytoene desaturase genes. Mutations in the other three did not affect color. The tetracycline marker was removed from the original transposon mutant, resulting in a pigment-free strain with wild-type growth properties useful as a tool for future experiments.

Plant colonization by pink-pigmented facultative methylotrophic bacteria (PPFMs).

Science.gov (United States)

Omer, Zahra S; Tombolini, Riccardo; Gerhardson, Berndt

2004-03-01

Bacteria belonging to the genus Methylobacterium are characterized by being able to rely on methanol as a sole carbon and energy source and by presenting a more or less intense pink reddish pigmentation. These bacteria, also referred to as pink-pigmented methylotrophic bacteria (PPFMs), are common inhabitants of the phyllosphere and are found in many other environmental samples. Since they grow slowly they are often overlooked and their impact on phyllosphere microbial communities and on the plants harboring them is not well studied nor has their ecology been elucidated. In a survey of PPFM colonization in three different agricultural sites, PPFM populations were identified on both red clover and winter wheat, but red clover was more consistently colonized. Isolations from collected leaves showed PPFM populations to decrease from spring towards summer, but they increased again towards the end of the cropping season. Isolates from red clover readily colonized winter wheat leaves and vice versa in greenhouse experiments, but population sizes were dependent on the application procedure. Tested isolates had also good potential to colonize the rhizosphere, especially after seed inoculations. Confocal scanning laser microscopy showed gfp-tagged isolates to colonize the surface of clover leaves by forming large aggregates.

Identification of marine methanol-utilizing bacteria

Energy Technology Data Exchange (ETDEWEB)

Yamamoto, M; Iwaki, H; Kouno, K; Inui, T

1980-01-01

A taxonomical study of 65 marine methanol-utilizing bacteria is described. They were Gram-negative, non-spore-forming rods with a polar flagellum and had marine bacterial properties and required vitamin B/sub 12/ for growth. All of them assimilated fructose in addition to C/sub 1/-compounds and produced acid oxidatively from fructose. Twenty-four strains assimilated only C/sub 1/-compounds. They were resistant to penicillin, oxytetracycline and 0/129 substance (Vibrio stat), and tolerant to 12% NaCl. Guanine-cytosine contents of deoxyribonucleic acid in typical strains fell in the range of 43.8 to 47.6%. Other morphological and physiological properties were almost the same as those of terrestrial methanol-utilizers. Bacteria in the first group (41 strains) were facultative methylotrophs and were divided into three subgroups by the assimilation of methylated amines, that is, subgroup I (30 strains) assimilated mono-, di- and tri-methylamine, subgroup II (9 strains) assimilated only mono-methylamine, the bacteria of subgroups I and II were named Alteromonas thalassomethanolica sp. nov. and subgroup III (2 strains) did not assimilate methylated amines, and was tentatively assigned as Alteromonas sp. The second group of bacteria (24 strains) was obligate methylotrophs, named Methylomonas thalassica sp. nov. and was divided into subgroup IV (15 strains) which assimilated mono-, di and tri-methylamine and subgroup V (9 strains) which assimilated mono-methylamine.

Comprehensive genomic analyses of the OM43 clade including a novel species from Red Sea indicate ecotype differentiation among marine methylotrophs

KAUST Repository

Jimenez Infante, Francy M.; Ngugi, David; Vinu, Manikandan; Alam, Intikhab; Kamau, Allan; Blom, Jochen; Bajic, Vladimir B.; Stingl, Ulrich

2015-01-01

The OM43 clade within the family Methylophilaceae of Betaproteobacteria represents a group of methylotrophs playing important roles in the metabolism of C1 compounds in marine environments and other aquatic environments around the globe. Using dilution-to-extinction cultivation techniques, we successfully isolated a novel species of this clade (designated here as MBRS-H7) from the ultra-oligotrophic open ocean waters of the central Red Sea. Phylogenomic analyses indicate that MBRS-H7 is a novel species, which forms a distinct cluster together with isolate KB13 from Hawaii (H-RS cluster) that is separate from that represented by strain HTCC2181 (from the Oregon coast). Phylogenetic analyses using the robust 16S–23S internal transcribed spacer revealed a potential ecotype separation of the marine OM43 clade members, which was further confirmed by metagenomic fragment recruitment analyses that showed trends of higher abundance in low chlorophyll and/or high temperature provinces for the H-RS cluster, but a preference for colder, highly productive waters for the HTCC2181 cluster. This potential environmentally driven niche differentiation is also reflected in the metabolic gene inventories, which in the case of H-RS include those conferring resistance to high levels of UV irradiation, temperature, and salinity. Interestingly, we also found different energy conservation modules between these OM43 subclades, namely the existence of the NADH:quinone oxidoreductase NUO system in the H-RS and the non-homologous NQR system in HTCC2181, which might have implications on their overall energetic yields.

Comprehensive genomic analyses of the OM43 clade including a novel species from Red Sea indicate ecotype differentiation among marine methylotrophs

KAUST Repository

Jimenez Infante, Francy M.

2015-12-11

The OM43 clade within the family Methylophilaceae of Betaproteobacteria represents a group of methylotrophs playing important roles in the metabolism of C1 compounds in marine environments and other aquatic environments around the globe. Using dilution-to-extinction cultivation techniques, we successfully isolated a novel species of this clade (designated here as MBRS-H7) from the ultra-oligotrophic open ocean waters of the central Red Sea. Phylogenomic analyses indicate that MBRS-H7 is a novel species, which forms a distinct cluster together with isolate KB13 from Hawaii (H-RS cluster) that is separate from that represented by strain HTCC2181 (from the Oregon coast). Phylogenetic analyses using the robust 16S–23S internal transcribed spacer revealed a potential ecotype separation of the marine OM43 clade members, which was further confirmed by metagenomic fragment recruitment analyses that showed trends of higher abundance in low chlorophyll and/or high temperature provinces for the H-RS cluster, but a preference for colder, highly productive waters for the HTCC2181 cluster. This potential environmentally driven niche differentiation is also reflected in the metabolic gene inventories, which in the case of H-RS include those conferring resistance to high levels of UV irradiation, temperature, and salinity. Interestingly, we also found different energy conservation modules between these OM43 subclades, namely the existence of the NADH:quinone oxidoreductase NUO system in the H-RS and the non-homologous NQR system in HTCC2181, which might have implications on their overall energetic yields.

Methylobacterium pseudosasicola sp. nov. and Methylobacterium phyllostachyos sp. nov., isolated from bamboo leaf surfaces.

Science.gov (United States)

Madhaiyan, Munusamy; Poonguzhali, Selvaraj

2014-07-01

Two strains of Gram-negative, methylotrophic bacteria, isolated because of their abilities to promote plant growth, were subjected to a polyphasic taxonomic study. The isolates were strictly aerobic, motile, pink-pigmented, facultatively methylotrophic, non-spore-forming rods. The chemotaxonomic characteristics of the isolates included the presence of C18 : 1ω7c as the major cellular fatty acid. The DNA G+C contents of strains BL36(T) and BL47(T) were 69.4 and 69.8 mol%, respectively. 16S rRNA gene sequence analysis of strains BL36(T) and BL47(T) placed them under the genus Methylobacterium, with the pairwise sequence similarity between them and the type strains of closely related species ranging from 97.2 to 99.0%. On the basis of their phenotypic and phylogenetic distinctiveness and the results of DNA-DNA hybridization analysis, the isolates represent two novel species within the genus Methylobacterium, for which the names Methylobacterium pseudosasicola sp. nov. (type strain BL36(T) = NBRC 105203(T) = ICMP 17621(T)) and Methylobacterium phyllostachyos sp. nov. (type strain BL47(T) = NBRC 105206(T) = ICMP 17619(T)) are proposed. © 2014 IUMS.

On the interpretation of rare events recorded by Kamiokande 2. and IMB detectors in association with occurrence of supernova 1987 A

International Nuclear Information System (INIS)

Krivoruchenko, M.I.

1989-01-01

A statistical analysis of angular distribution of neutrino events observed in Kamiokande 2. and IMB detectors from supernova SN 1987 A is carried out. The Neyman-Pearson test is applied to each of the events in testing the hypothesis ν-bar e p→e + n against the alternative one νe→νe. The confidence level of the hypothesis that the recorded events all represent ν-bar e p→e + n inelastic scatterings against possible alternatives is found with the use of the Kolmogorov and Mises tests to be 2% and 0.9%, respectively. The number of νe→νe events is estimated to be from 3 to 11 with probability ≥0.9. The current supernova models fail to give a satisfactory account of the angular distribution data

A statistical analysis of angular distribution of neutrino events observed in Kamiokande II and IMB detectors from supernova SN 1987 A

International Nuclear Information System (INIS)

Krivoruchenko, M.I.

1989-01-01

A detailed statistical analysis of angular distribution of neutrino events observed in Kamiokande II and IMB detectors on UT 07:35, 2/23'87 is carried out. Distribution functions of the mean scattering angles in the reaction anti υ e p→e + n and υe→υe are constructed with account taken of the multiple Coulomb scattering and the experimental angular errors. The Smirnov and Wald-Wolfowitz run tests are used to test the hypothesis that the angular distributions of events from the two detectors agree with each other. We test with the use of the Kolmogorov and Mises statistical criterions the hypothesis that the recorded events all represent anti υ e p→e + n inelastic scatterings. Then the Neyman-Pearson test is applied to each event in testing the hypothesis anti υ e p→e + n against the alternative υe→υe. The hypotheses that the number of elastic events equals s=0, 1, 2, ... against the alternatives s≠0, 1, 2, ... are tested on the basis of the generalized likelihood ratio criterion. The confidence intervals for the number of elastic events are also constructed. The current supernova models fail to give a satisfactory account of the angular distribution data. (orig.)

Effect of nitrogen source on methanol oxidation and genetic diversity of methylotrophic mixed cultures enriched from pulp and paper mill biofilms.

Science.gov (United States)

Babbitt, Callie W; Lindner, Angela S

2011-04-01

Methanol-oxidizing bacteria may play an important role in the development and use of biological treatment systems for the removal of methanol from industrial effluents. Optimization of methanol degradation potential in such systems is contingent on availability of nutrients, such as nitrogen, in the most favorable form and concentration. To that end, this study examined the variation in growth, methanol degradation, and bacterial diversity of two mixed methylotrophic cultures that were provided nitrogen either as ammonium or nitrate and in three different concentrations. Methanol-degrading cultures were enriched from biofilms sampled at a pulp and paper mill and grown in liquid batch culture with methanol as the only carbon source and either ammonium or nitrate as the only added nitrogen source. Results indicate that growth and methanol removal of the mixed cultures increase directly with increased nitrogen, added in either form. However, methanol removal and bacterial diversity, as observed by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) methods, were higher when using nitrate as the nitrogen source for enrichment and growth, rather than ammonium. Based on results described here, nitrate may potentially be a better nitrogen source when enriching or working with mixed methylotrophic cultures, and possibly more effective when used as a nutrient addition to biofilters.

Genome sequence of herpes simplex virus 1 strain KOS.

Science.gov (United States)

Macdonald, Stuart J; Mostafa, Heba H; Morrison, Lynda A; Davido, David J

2012-06-01

Herpes simplex virus type 1 (HSV-1) strain KOS has been extensively used in many studies to examine HSV-1 replication, gene expression, and pathogenesis. Notably, strain KOS is known to be less pathogenic than the first sequenced genome of HSV-1, strain 17. To understand the genotypic differences between KOS and other phenotypically distinct strains of HSV-1, we sequenced the viral genome of strain KOS. When comparing strain KOS to strain 17, there are at least 1,024 small nucleotide polymorphisms (SNPs) and 172 insertions/deletions (indels). The polymorphisms observed in the KOS genome will likely provide insights into the genes, their protein products, and the cis elements that regulate the biology of this HSV-1 strain.

Screening and characterization of alkaline protease produced by a pink pigmented facultative methylotrophic (PPFM strain, MSF 46

Directory of Open Access Journals (Sweden)

Shanmugam Jayashree

2014-12-01

Full Text Available Among the various bacterial isolates, the strain MSF 46 isolated from thorn forest soil samples, Tamil Nadu, India, was screened and characterized for its proteolytic activity. While the 16S rRNA sequencing and biochemical characterization revealed that the strain closely resembles Methylobacterium sp., methylotrophy of the strain was confirmed by the sequence homology of mxaF gene with other relative Methylobacterium sp. The alkaline protease was purified to homogeneity using DEAE cellulose ion exchange chromatography, with a 5.2-fold increase in specific activity and 34% recovery. The apparent molecular weight of the enzyme was determined as 40 kDa by SDS–PAGE study. The pH and temperature optima were 9.0 and 50 °C respectively with maximum protease activity of 1164 U/ml. Protease of MSF 46 was active in a broad pH range 7.0–11.0 with a maximum at pH 8.5 and exhibited thermostability at 50 °C. The enzyme activity was inhibited by PMSF but showed stability with Tween 20, Triton X-100 and hydrogen peroxide. Nearly 30% reduction in enzyme activity was observed in the presence of EDTA and DTT. The enzyme was effective in hydrolyzing gelatin, skimmed milk and blood clots and exhibited the potency for dehairing of goat skin and removing blood stain from cotton fabric. Significant morphological changes were observed under scanning electron microscope between cells grown in normal and casein amended medium. This first detailed report on the production of alkaline protease by a PPFM strain appears promising toward development of protocols for mass production, study of the molecular mechanism and other applications.

Molecular typing of Brucella melitensis endemic strains and differentiation from the vaccine strain Rev-1.

Science.gov (United States)

Noutsios, Georgios T; Papi, Rigini M; Ekateriniadou, Loukia V; Minas, Anastasios; Kyriakidis, Dimitrios A

2012-03-01

In the present study forty-four Greek endemic strains of Br. melitensis and three reference strains were genotyped by Multi locus Variable Number Tandem Repeat (ML-VNTR) analysis based on an eight-base pair tandem repeat sequence that was revealed in eight loci of Br. melitensis genome. The forty-four strains were discriminated from the vaccine strain Rev-1 by Restriction Fragment Length Polymorphism (RFLP) and Denaturant Gradient Gel Electrophoresis (DGGE). The ML-VNTR analysis revealed that endemic, reference and vaccine strains are genetically closely related, while most of the loci tested (1, 2, 4, 5 and 7) are highly polymorphic with Hunter-Gaston Genetic Diversity Index (HGDI) values in the range of 0.939 to 0.775. Analysis of ML-VNTRs loci stability through in vitro passages proved that loci 1 and 5 are non stable. Therefore, vaccine strain can be discriminated from endemic strains by allele's clusters of loci 2, 4, 6 and 7. RFLP and DGGE were also employed to analyse omp2 gene and reveled different patterns among Rev-1 and endemic strains. In RFLP, Rev-1 revealed three fragments (282, 238 and 44 bp), while endemic strains two fragments (238 and 44 bp). As for DGGE, the electrophoretic mobility of Rev-1 is different from the endemic strains due to heterologous binding of DNA chains of omp2a and omp2b gene. Overall, our data show clearly that it is feasible to genotype endemic strains of Br. melitensis and differentiate them from vaccine strain Rev-1 with ML-VNTR, RFLP and DGGE techniques. These tools can be used for conventional investigations in brucellosis outbreaks.

Improved thermal stability and hole mobilities in a strained-Si/strained-Si1-yGe y/strained-Si heterostructure grown on a relaxed Si1-xGe x buffer

International Nuclear Information System (INIS)

Gupta, Saurabh; Lee, Minjoo L.; Isaacson, David M.; Fitzgerald, Eugene A.

2005-01-01

A dual channel heterostructure consisting of strained-Si/strained-Si 1-y Ge y on relaxed Si 1-x Ge x (y > x), provides a platform for fabricating metal-oxide-semiconductor field-effect transistors (MOSFETs) with high hole mobilities (μ eff ) which depend directly on Ge concentration and strain in the strained-Si 1-y Ge y layer. Ge out-diffuses from the strained-Si 1-y Ge y layer into relaxed Si 1-x Ge x during high temperature processing, reducing peak Ge concentration and strain in the strained-Si 1-y Ge y layer and degrades hole μ eff in these dual channel heterostructures. A heterostructure consisting of strained-Si/strained-Si 1-y Ge y /strained-Si, referred to as a trilayer heterostructure, grown on relaxed Si 1-x Ge x has much reduced Ge out-flux from the strained-Si 1-y Ge y layer and retains higher μ eff after thermal processing. Improved hole μ eff over similar dual channel heterostructures is also observed in this heterostructure. This could be a result of preventing the hole wavefunction tunneling into the low μ eff relaxed Si 1-x Ge x layer due to the additional valence band offset provided by the underlying strained-Si layer. A diffusion coefficient has been formulated and implemented in a finite difference scheme for predicting the thermal budget of the strained SiGe heterostructures. It shows that the trilayer heterostructures have superior thermal budgets at higher Ge concentrations. Ring-shaped MOSFETs were fabricated on both platforms and subjected to various processing temperatures in order to compare the extent of μ eff reduction with thermal budget. Hole μ eff enhancements are retained to a much higher extent in a trilayer heterostructure after high temperature processing as compared to a dual channel heterostructure. The improved thermal stability and hole μ eff of a trilayer heterostructure makes it an ideal platform for fabricating high μ eff MOSFETs that can be processed over higher temperatures without significant losses in hole �

High-frequency transformation of a methylotrophic yeast, Candida boidinii, with autonomously replicating plasmids which are also functional in Saccharomyces cerevisiae.

Science.gov (United States)

Sakai, Y; Goh, T K; Tani, Y

1993-06-01

We have developed a transformation system which uses autonomous replicating plasmids for a methylotrophic yeast, Candida boidinii. Two autonomous replication sequences, CARS1 and CARS2, were newly cloned from the genome of C. boidinii. Plasmids having both a CARS fragment and the C. boidinii URA3 gene transformed C. boidinii ura3 cells to Ura+ phenotype at frequencies of up to 10(4) CFU/micrograms of DNA. From Southern blot analysis, CARS plasmids seemed to exist in polymeric forms as well as in monomeric forms in C. boidinii cells. The C. boidinii URA3 gene was overexpressed in C. boidinii on these CARS vectors. CARS1 and CARS2 were found to function as an autonomous replicating element in Saccharomyces cerevisiae as well. Different portions of the CARS1 sequence were needed for autonomous replicating activity in C. boidinii and S. cerevisiae. C. boidinii could also be transformed with vectors harboring a CARS fragment and the S. cerevisiae URA3 gene.

Prevention of pink-pigmented methylotrophic bacteria (Methylohacterium mesophilicum) contamination of plant tissue cultures.

Science.gov (United States)

Chanprame, S; Todd, J J; Widholm, J M

1996-12-01

Pink-pigmented facultative methylotrophic bacteria (PPFMs) have been found on the surfaces of leaves of most plants tested. We found PPFMs on the leaf surfaces of all 40 plants (38 species) tested and on soybean pods by pressing onto AMS medium with methanol as the sole carbon source. The abundance ranged from 0.5 colony forming unit (cfu) /cm(2) to 69.4 cfu/cm(2) on the leaf surfaces. PPFMs were found in homogenized leaf tissues of only 4 of the species after surface disinfestation with 1.05% sodium hypochlorite and were rarely found in cultures initiated from surface disinfested Datura innoxia leaves or inside surface disinfested soybean pods. Of 20 antibiotics tested for PPFM growth inhibition, rifampicin was the most effective and of seven others which also inhibited PPFM growth, cefotaxime should be the most useful due to the expected low plant cell toxicity. These antibiotics could be used in concert with common surface sterilization procedures to prevent the introduction or to eliminate PPFM bacteria in tissue cultures. Thus, while PPFMs are present on the surfaces of most plant tissues, surface disinfestation alone can effectively remove them so that uncontaminated tissue cultures can be initiated in most cases.

Recombinant protein expression in Pichia pastoris strains with an engineered methanol utilization pathway

Science.gov (United States)

2012-01-01

Βackground The methylotrophic yeast Pichia pastoris has become an important host organism for recombinant protein production and is able to use methanol as a sole carbon source. The methanol utilization pathway describes all the catalytic reactions, which happen during methanol metabolism. Despite the importance of certain key enzymes in this pathway, so far very little is known about possible effects of overexpressing either of these key enzymes on the overall energetic behavior, the productivity and the substrate uptake rate in P. pastoris strains. Results A fast and easy-to-do approach based on batch cultivations with methanol pulses was used to characterize different P. pastoris strains. A strain with MutS phenotype was found to be superior over a strain with Mut+ phenotype in both the volumetric productivity and the efficiency in expressing recombinant horseradish peroxidase C1A. Consequently, either of the enzymes dihydroxyacetone synthase, transketolase or formaldehyde dehydrogenase, which play key roles in the methanol utilization pathway, was co-overexpressed in MutS strains harboring either of the reporter enzymes horseradish peroxidase or Candida antarctica lipase B. Although the co-overexpression of these enzymes did not change the stoichiometric yields of the recombinant MutS strains, significant changes in the specific growth rate, the specific substrate uptake rate and the specific productivity were observed. Co-overexpression of dihydroxyacetone synthase yielded a 2- to 3-fold more efficient conversion of the substrate methanol into product, but also resulted in a reduced volumetric productivity. Co-overexpression of formaldehyde dehydrogenase resulted in a 2-fold more efficient conversion of the substrate into product and at least similar volumetric productivities compared to strains without an engineered methanol utilization pathway, and thus turned out to be a valuable strategy to improve recombinant protein production. Conclusions Co

Recombinant protein expression in Pichia pastoris strains with an engineered methanol utilization pathway

Directory of Open Access Journals (Sweden)

Krainer Florian W

2012-02-01

Full Text Available Abstract Βackground The methylotrophic yeast Pichia pastoris has become an important host organism for recombinant protein production and is able to use methanol as a sole carbon source. The methanol utilization pathway describes all the catalytic reactions, which happen during methanol metabolism. Despite the importance of certain key enzymes in this pathway, so far very little is known about possible effects of overexpressing either of these key enzymes on the overall energetic behavior, the productivity and the substrate uptake rate in P. pastoris strains. Results A fast and easy-to-do approach based on batch cultivations with methanol pulses was used to characterize different P. pastoris strains. A strain with MutS phenotype was found to be superior over a strain with Mut+ phenotype in both the volumetric productivity and the efficiency in expressing recombinant horseradish peroxidase C1A. Consequently, either of the enzymes dihydroxyacetone synthase, transketolase or formaldehyde dehydrogenase, which play key roles in the methanol utilization pathway, was co-overexpressed in MutS strains harboring either of the reporter enzymes horseradish peroxidase or Candida antarctica lipase B. Although the co-overexpression of these enzymes did not change the stoichiometric yields of the recombinant MutS strains, significant changes in the specific growth rate, the specific substrate uptake rate and the specific productivity were observed. Co-overexpression of dihydroxyacetone synthase yielded a 2- to 3-fold more efficient conversion of the substrate methanol into product, but also resulted in a reduced volumetric productivity. Co-overexpression of formaldehyde dehydrogenase resulted in a 2-fold more efficient conversion of the substrate into product and at least similar volumetric productivities compared to strains without an engineered methanol utilization pathway, and thus turned out to be a valuable strategy to improve recombinant protein

Comprehensive Genomic Analyses of the OM43 Clade, Including a Novel Species from the Red Sea, Indicate Ecotype Differentiation among Marine Methylotrophs

Science.gov (United States)

Jimenez-Infante, Francy; Ngugi, David Kamanda; Vinu, Manikandan; Alam, Intikhab; Kamau, Allan Anthony; Blom, Jochen; Bajic, Vladimir B.

2015-01-01

The OM43 clade within the family Methylophilaceae of Betaproteobacteria represents a group of methylotrophs that play important roles in the metabolism of C1 compounds in marine environments and other aquatic environments around the globe. Using dilution-to-extinction cultivation techniques, we successfully isolated a novel species of this clade (here designated MBRS-H7) from the ultraoligotrophic open ocean waters of the central Red Sea. Phylogenomic analyses indicate that MBRS-H7 is a novel species that forms a distinct cluster together with isolate KB13 from Hawaii (Hawaii-Red Sea [H-RS] cluster) that is separate from the cluster represented by strain HTCC2181 (from the Oregon coast). Phylogenetic analyses using the robust 16S-23S internal transcribed spacer revealed a potential ecotype separation of the marine OM43 clade members, which was further confirmed by metagenomic fragment recruitment analyses that showed trends of higher abundance in low-chlorophyll and/or high-temperature provinces for the H-RS cluster but a preference for colder, highly productive waters for the HTCC2181 cluster. This potential environmentally driven niche differentiation is also reflected in the metabolic gene inventories, which in the case of the H-RS cluster include those conferring resistance to high levels of UV irradiation, temperature, and salinity. Interestingly, we also found different energy conservation modules between these OM43 subclades, namely, the existence of the NADH:quinone oxidoreductase complex I (NUO) system in the H-RS cluster and the nonhomologous NADH:quinone oxidoreductase (NQR) system in the HTCC2181 cluster, which might have implications for their overall energetic yields. PMID:26655752

Effect of uniaxial strain on adatom diffusion across {l_brace}1 1 1{r_brace}-faceted step

Energy Technology Data Exchange (ETDEWEB)

Yang Jianyu, E-mail: wuliyangjianyu@yahoo.com.cn [Department of Maths and Physics, Hunan Institute of Engineering, Donghu Street, Xiangtan 411104 (China); Hu Wangyu, E-mail: Wangyuhu2001@yahoo.com.cn [Department of Applied Physics, Hunan University, Changsha 410082 (China); Tang Jianfeng [Department of Applied Physics, Hunan Agricultural University, Changsha 410128 (China)

2011-02-01

Diffusion of Pt adatom across the strained {l_brace}1 1 1{r_brace}-faceted step is studied by embedded atom method along with nudged elastic band method. For adatom on the flat (1 1 1) surface, the anisotropic diffusion behavior is found as the uniaxial strain is imposed. For the strained {l_brace}1 1 1{r_brace}-faceted step, our results show that the maximum energy barrier for adatom crossing step edge remains approximately constant as the strain varied from -1.0% to 1.0%, and there is a rise as the larger uniaxial strain is applied. The calculated energy barrier for adatom diffusion along the step edge increases with increasing tensile strain, and the slope of the straight line is small.

GC-rich DNA elements enable replication origin activity in the methylotrophic yeast Pichia pastoris.

Science.gov (United States)

Liachko, Ivan; Youngblood, Rachel A; Tsui, Kyle; Bubb, Kerry L; Queitsch, Christine; Raghuraman, M K; Nislow, Corey; Brewer, Bonita J; Dunham, Maitreya J

2014-03-01

The well-studied DNA replication origins of the model budding and fission yeasts are A/T-rich elements. However, unlike their yeast counterparts, both plant and metazoan origins are G/C-rich and are associated with transcription start sites. Here we show that an industrially important methylotrophic budding yeast, Pichia pastoris, simultaneously employs at least two types of replication origins--a G/C-rich type associated with transcription start sites and an A/T-rich type more reminiscent of typical budding and fission yeast origins. We used a suite of massively parallel sequencing tools to map and dissect P. pastoris origins comprehensively, to measure their replication dynamics, and to assay the global positioning of nucleosomes across the genome. Our results suggest that some functional overlap exists between promoter sequences and G/C-rich replication origins in P. pastoris and imply an evolutionary bifurcation of the modes of replication initiation.

Mating-type switching by chromosomal inversion in methylotrophic yeasts suggests an origin for the three-locus Saccharomyces cerevisiae system.

Science.gov (United States)

Hanson, Sara J; Byrne, Kevin P; Wolfe, Kenneth H

2014-11-11

Saccharomyces cerevisiae has a complex system for switching the mating type of haploid cells, requiring the genome to have three mating-type (MAT)-like loci and a mechanism for silencing two of them. How this system originated is unknown, because the three-locus system is present throughout the family Saccharomycetaceae, whereas species in the sister Candida clade have only one locus and do not switch. Here we show that yeasts in a third clade, the methylotrophs, have a simpler two-locus switching system based on reversible inversion of a section of chromosome with MATa genes at one end and MATalpha genes at the other end. In Hansenula polymorpha the 19-kb invertible region lies beside a centromere so that, depending on the orientation, either MATa or MATalpha is silenced by centromeric chromatin. In Pichia pastoris, the orientation of a 138-kb invertible region puts either MATa or MATalpha beside a telomere and represses transcription of MATa2 or MATalpha2. Both species are homothallic, and inversion of their MAT regions can be induced by crossing two strains of the same mating type. The three-locus system of S. cerevisiae, which uses a nonconservative mechanism to replace DNA at MAT, likely evolved from a conservative two-locus system that swapped genes between expression and nonexpression sites by inversion. The increasing complexity of the switching apparatus, with three loci, donor bias, and cell lineage tracking, can be explained by continuous selection to increase sporulation ability in young colonies. Our results provide an evolutionary context for the diversity of switching and silencing mechanisms.

[Virulence markers of Escherichia coli O1 strains].

Science.gov (United States)

Makarova, M A; Kaftyreva, L A; Grigor'eva, N S; Kicha, E V; Lipatova, L A

2011-01-01

To detect virulence genes in clinical isolates of Escherichia coli O1 using polymerase chain reaction (PCR). One hundred and twenty strains of E.coli O1 strains isolated from faeces of patients with acute diarrhea (n = 45) and healthy persons (n = 75) were studied. PCR with primers for rfb and fliC genes, which control synthesis of O- and H- antigens respectively, was used. Fourteen virulence genes (pap, aaf, sfa, afa, eaeA, bfpA, ial, hly, cnf, stx1, stx2, lt, st, and aer) were detected by PCR primers. K1-antigen was determined by Pastorex Meningo B/E. coli O1 kit (Bio-Rad). rfb gene controlling O-antigen synthesis in serogroup O1 as well as fliC gene controlling synthesis of H7 and K1 antigens were detected in all strains. Thus all E. coli strains had antigenic structure O1:K1 :H-:F7. Virulence genes aafl, sfa, afa, eaeA, bfpA, ial, hly, cnf, stx1, stx2, lt, and st were not detected. All strains owned pap and aer genes regardless of the presence of acute diarrhea symptoms. It was shown that E. coli O1:KI:H-:F7 strains do not have virulence genes which are characteristic for diarrhea-causing Escherichia. In accordance with the presence of pap and aer genes they could be attributed to uropathogenic Escherichia (UPEC) or avian-pathogenic Escherichia (APEC). It is necessary to detect virulence factors in order to determine E. coli as a cause of intestinal infection.

GC-rich DNA elements enable replication origin activity in the methylotrophic yeast Pichia pastoris.

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Ivan Liachko

2014-03-01

Full Text Available The well-studied DNA replication origins of the model budding and fission yeasts are A/T-rich elements. However, unlike their yeast counterparts, both plant and metazoan origins are G/C-rich and are associated with transcription start sites. Here we show that an industrially important methylotrophic budding yeast, Pichia pastoris, simultaneously employs at least two types of replication origins--a G/C-rich type associated with transcription start sites and an A/T-rich type more reminiscent of typical budding and fission yeast origins. We used a suite of massively parallel sequencing tools to map and dissect P. pastoris origins comprehensively, to measure their replication dynamics, and to assay the global positioning of nucleosomes across the genome. Our results suggest that some functional overlap exists between promoter sequences and G/C-rich replication origins in P. pastoris and imply an evolutionary bifurcation of the modes of replication initiation.

Oxidation of hydroxylamine by cytochrome P-460 of the obligate methylotroph Methylococcus capsulatus Bath.

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Zahn, J A; Duncan, C; DiSpirito, A A

1994-01-01

An enzyme capable of the oxidation of hydroxylamine to nitrite was isolated from the obligate methylotroph Methylococcus capsulatus Bath. The absorption spectra in cell extracts, electron paramagnetic resonance spectra, molecular weight, covalent attachment of heme group to polypeptide, and enzymatic activities suggest that the enzyme is similar to cytochrome P-460, a novel iron-containing protein previously observed only in Nitrosomonas europaea. The native and subunit molecular masses of the M. capsulatus Bath protein were 38,900 and 16,390 Da, respectively; the isoelectric point was 6.98. The enzyme has approximately one iron and one copper atom per subunit. The electron paramagnetic resonance spectrum of the protein showed evidence for a high-spin ferric heme. In contrast to the enzyme from N. europaea, a 13-nm blue shift in the soret band of the ferrocytochrome (463 nm in cell extracts to 450 nm in the final sample) occurred during purification. The amino acid composition and N-terminal amino acid sequence of the enzyme from M. capsulatus Bath was similar but not identical to those of cytochrome P-460 of N. europaea. In cell extracts, the identity of the biological electron acceptor is as yet unestablished. Cytochrome c-555 is able to accept electrons from cytochrome P-460, although the purified enzyme required phenazine methosulfate for maximum hydroxylamine oxidation activity (specific activity, 366 mol of O2 per s per mol of enzyme). Hydroxylamine oxidation rates were stimulated approximately 2-fold by 1 mM cyanide and 1.5-fold by 0.1 mM 8-hydroxyquinoline. Images PMID:7928947

Characterization of recombinant human lysosomal beta-hexosaminidases produced in the methylotrophic yeast Pichia pastoris

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Angela Johana Espejo Mojica

2016-08-01

Full Text Available β-hexosaminidases (Hex are dimeric enzymes involved in the lysosomal degradation of glycolipids and glycans. They are formed by α- and/or β-subunits encoded byHEXA and HEXB genes, respectively. Mutations in these genes lead to Tay Sachs or Sandhoff diseases, which are neurodegenerative disorders caused by the accumulation of non-degraded glycolipids. Although tissue-derived Hex have been widely characterized, limited information is available for recombinant β-hexosaminidases. In this study, human lysosomal recombinant Hex (rhHex-A, rhHex-B, and rhHex-S were produced in the methylotrophic yeast Pichia pastoris GS115. The highest specific enzyme activities were 13,124 for rhHexA; 12,779 for rhHex-B; and 14,606 U .mg-1 for rhHex-S. These results were 25- to 50-fold higher than those obtained from normal human leukocytes. Proteins were purified and characterized at different pH and temperature conditions. All proteins were stable at acidic pH, and at 4 °C and 37 °C. At 45 °C rhHex-S was completely inactivated, while rhHex-A and rhHex-B showed high stability. This study demonstrates P. pastoris GS115 potential for polymeric lysosomal enzyme production, and describes the characterization of recombinant β-hexosaminidases produced within the same host.

High strain rate tensile properties of annealed 2 1/4 Cr--1 Mo steel

International Nuclear Information System (INIS)

Klueh, R.L.; Oakes, R.E. Jr.

1975-01-01

The high strain rate tensile properties of annealed 2 1 / 4 Cr-1 Mo steel were determined and the tensile behavior from 25 to 566 0 C and strain rates of 2.67 x 10 -6 to 144/s were described. Above 0.1/s at 25 0 C, both the yield stress and the ultimate tensile strength increased rapidly with increasing strain rate. As the temperature was increased, a dynamic strain aging peak appeared in the ultimate tensile strength-temperature curves. The peak height was a maximum at about 350 0 C and 2.67 x 10 -6 /s. With increasing strain rate, a peak of decreased height occurred at progressively higher temperatures. The major effect of strain rate on ductility occurred at elevated temperatures, where a decrease in strain rate caused an increase in total elongation and reduction in area

Strain-based HLA association analysis identified HLA-DRB1*09:01 associated with modern strain tuberculosis.

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Toyo-Oka, L; Mahasirimongkol, S; Yanai, H; Mushiroda, T; Wattanapokayakit, S; Wichukchinda, N; Yamada, N; Smittipat, N; Juthayothin, T; Palittapongarnpim, P; Nedsuwan, S; Kantipong, P; Takahashi, A; Kubo, M; Sawanpanyalert, P; Tokunaga, K

2017-09-01

Tuberculosis (TB) occurs as a result of complex interactions between the host immune system and pathogen virulence factors. Human leukocyte antigen (HLA) class II molecules play an important role in the host immune system. However, no study has assessed the association between HLA class II genes and susceptibility to TB caused by specific strains. This study investigated the possible association of HLA class II genes with TB caused by modern and ancient Mycobacterium tuberculosis (MTB). The study included 682 patients with TB and 836 control subjects who were typed for HLA-DRB1 and HLA-DQB1 alleles. MTB strains were classified using a large sequence polymorphism typing method. Association analysis was performed using common HLA alleles and haplotypes in different MTB strains. HLA association analysis of patients infected with modern MTB strains showed significant association for HLA-DRB1*09:01 (odds ratio [OR] = 1.82; P-value = 9.88 × 10 -4 ) and HLA-DQB1*03:03 alleles (OR = 1.76; P-value = 1.31 × 10 -3 ) with susceptibility to TB. Haplotype analysis confirmed that these alleles were in strong linkage disequilibrium and did not exert an interactive effect. Thus, the results of this study showed an association between HLA class II genes and susceptibility to TB caused by modern MTB strains, suggesting the importance of strain-specific analysis to determine susceptibility genes associated with TB. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Microbiological Synthesis of 2H-Labeled Phenylalanine, Alanine, Valine, and Leucine/Isoleucine with Different Degrees of Deuterium Enrichment by the Gram-Positive Facultative Methylotrophic Bacterium Вrevibacterium Methylicum

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Oleg V. Mosin, PhD¹

2013-06-01

Full Text Available The microbiological synthesis of [2H]amino acids was performed by the conversion of low molecular weight substrates ([U-2H]MeOH and 2H2O using the Gram-positive aerobic facultative methylotrophic bacterium Brevibacterium methylicum, an L-phenylalanine producer, realizing the NAD+ dependent methanol dehydrogenase (EC 1.6.99.3 variant of the ribulose-5-monophosphate (RuMP cycle of carbon assimilation. In this process, the adapted cells of the methylotroph with enhanced growth characteristics were used on a minimal salt medium M9, supplemented with 2% (v/v [U-2H]MeOH and an increasing gradient of 2Н2O concentration from 0; 24.5, 49.0; 73.5 up to 98% (v/v 2Н2O. Alanine, valine, and leucine/isoleucine were produced and accumulated exogeneously in quantities of 5–6 mol, in addition to the main product of biosynthesis. This method enables the production of [2Н]amino acids with different degrees of deuterium enrichment, depending on the 2Н2O concentration in the growth medium, from 17 at.% 2Н (on the growth medium with 24.5 % (v/v 2Н2О up to 75 at.% 2Н (on the growth medium with 98 % (v/v 2Н2О. This has been confirmed with the data from the electron impact (EI mass spectrometry analysis of the methyl ethers of N-dimethylamino(naphthalene-5-sulfochloride [2H]amino acids under these experimental conditions.

A novel pink-pigmented facultative methylotroph, Methylobacterium thiocyanatum sp. nov., capable of growth on thiocyanate or cyanate as sole nitrogen sources.

Science.gov (United States)

Wood, A P; Kelly, D P; McDonald, I R; Jordan, S L; Morgan, T D; Khan, S; Murrell, J C; Borodina, E

1998-02-01

The isolation and properties of a novel species of pink-pigmented methylotroph, Methylobacterium thiocyanatum, are described. This organism satisfied all the morphological, biochemical, and growth-substrate criteria to be placed in the genus Methylobacterium. Sequencing of the gene encoding its 16S rRNA confirmed its position in this genus, with its closest phylogenetic relatives being M. rhodesianum, M. zatmanii and M. extorquens, from which it differed in its ability to grow on several diagnostic substrates. Methanol-grown organisms contained high activities of hydroxypyruvate reductase -3 micromol NADH oxidized min-1 (mg crude extract protein)-1], showing that the serine pathway was used for methylotrophic growth. M. thiocyanatum was able to use thiocyanate or cyanate as the sole source of nitrogen for growth, and thiocyanate as the sole source of sulfur in the absence of other sulfur compounds. It tolerated high concentrations (at least 50 mM) of thiocyanate or cyanate when these were supplied as nitrogen sources. Growing cultures degraded thiocyanate to produce thiosulfate as a major sulfur end product, apparently with the intermediate formation of volatile sulfur compounds (probably hydrogen sulfide and carbonyl sulfide). Enzymatic hydrolysis of thiocyanate by cell-free extracts was not demonstrated. Cyanate was metabolized by means of a cyanase enzyme that was expressed at approximately sevenfold greater activity during growth on thiocyanate [Vmax 634 +/- 24 nmol NH3 formed min-1 (mg protein)-1] than on cyanate [89 +/- 9 nmol NH3 min-1 (mg protein)-1]. Kinetic study of the cyanase in cell-free extracts showed the enzyme (1) to exhibit high affinity for cyanate (Km 0.07 mM), (2) to require bicarbonate for activity, (3) to be subject to substrate inhibition by cyanate and competitive inhibition by thiocyanate (Ki 0.65 mM), (4) to be unaffected by 1 mM ammonium chloride, (5) to be strongly inhibited by selenocyanate, and (6) to be slightly inhibited by 5 m

History and genomic sequence analysis of the herpes simplex virus 1 KOS and KOS1.1 sub-strains.

Science.gov (United States)

Colgrove, Robert C; Liu, Xueqiao; Griffiths, Anthony; Raja, Priya; Deluca, Neal A; Newman, Ruchi M; Coen, Donald M; Knipe, David M

2016-01-01

A collection of genomic DNA sequences of herpes simplex virus (HSV) strains has been defined and analyzed, and some information is available about genomic stability upon limited passage of viruses in culture. The nature of genomic change upon extensive laboratory passage remains to be determined. In this report we review the history of the HSV-1 KOS laboratory strain and the related KOS1.1 laboratory sub-strain, also called KOS (M), and determine the complete genomic sequence of an early passage stock of the KOS laboratory sub-strain and a laboratory stock of the KOS1.1 sub-strain. The genomes of the two sub-strains are highly similar with only five coding changes, 20 non-coding changes, and about twenty non-ORF sequence changes. The coding changes could potentially explain the KOS1.1 phenotypic properties of increased replication at high temperature and reduced neuroinvasiveness. The study also provides sequence markers to define the provenance of specific laboratory KOS virus stocks. Copyright © 2015 Elsevier Inc. All rights reserved.

The stress and strain analysis research of class 1 eqnipments

International Nuclear Information System (INIS)

Ye Yuanwu; Tang Long; Wang Yueying; Qi Min; Yu Huajin

2008-01-01

The class 1 equipment is very important in the nuclear device, in the design and testing process required to carry out their stress and strain analysis, so as to ensure their safety. There are two ways to get stress and strain analysis of the class 1 equipment, the theoretical and experimental methods. Through theoretical method can get the stress and strain of the class 1 equipment, so as to provide a basis for the design of the equipment; through the experimental method to verify the accuracy of the theoretical methods and provide a basis for the safety assessment of the equipment. The main ressel of CEFR (China Experimental Fast Reactor) is the class 1 equipment. In this paper, according to the stress and strain analysis research of CEFR main vessel, the theories and expperimental methods of nuclear class 1 equipments stress and strain analysis has been described. (authors)

[Analysis of DNA-DNA homologies in obligate methylotrophic bacteria].

Science.gov (United States)

Doronina, N V; Govorukhina, N I; Lysenko, A M; Trotsenko, Iu A

1988-01-01

The genotypic affinity of 19 bacterial strains obligately dependent on methanol or methylamine as carbon and energy sources was studied by techniques of molecular DNA hybridization. The high homology level (35-88%) between motile strain Methylophilus methanolovorus V-1447D and nonmotile strain Methylobacillus sp. VSB-792 as well as other motile strains (Pseudomonas methanolica ATCC 21704, Methylomonas methanolica NRRL 5458, Pseudomonas sp. W6, strain A3) indicates that all of them belong to one genus. Rather high level of homology (62-63%) was found between Methylobacillus glycogenes ATCC 29475 and Pseudomonas insueta ATCC 21276 and strain G-10. The motile strain Methylophilus methylotrophus NCIB 10515 has a low homology (below 20%) to other of the studied obligate methylobacteria. Therefore, at least two genetically different genera of obligate methylobacteria can be distinguished, namely Methylophilus and Methylobacillus, the latter being represented by both motile and nonmotile forms.

Crystal structures of complexes of NAD+-dependent formate dehydrogenase from methylotrophic bacterium Pseudomonas sp. 101 with formate

International Nuclear Information System (INIS)

Filippova, E. V.; Polyakov, K. M.; Tikhonova, T. V.; Stekhanova, T. N.; Boiko, K. M.; Sadykhov, I. G.; Tishkov, V. I.; Popov, V. O.; Labru, N.

2006-01-01

Formate dehydrogenase (FDH) from the methylotrophic bacterium Pseudomonas sp. 101 catalyzes oxidation of formate to NI 2 with the coupled reduction of nicotinamide adenine dinucleotide (NAD + ). The three-dimensional structures of the apo form (the free enzyme) and the holo form (the ternary FDH-NAD + -azide complex) of FDH have been established earlier. In the present study, the structures of FDH complexes with formate are solved at 2.19 and 2.28 A resolution by the molecular replacement method and refined to the R factors of 22.3 and 20.5%, respectively. Both crystal structures contain four protein molecules per asymmetric unit. These molecules form two dimers identical to the dimer of the apo form of FDH. Two possible formatebinding sites are found in the active site of the FDH structure. In the complexes the sulfur atom of residue Cys354 exists in the oxidized state

Desulfurization of dibenzothiophene by Corynebacterium sp. strain SY1

International Nuclear Information System (INIS)

Omori, Toshio; Monna, L.; Saiki, Yuko; Kodama, Tohru

1992-01-01

Strain SY1, identified as a Corynebacterium sp., was isolated on the basis of the ability to utilize dibenzothiophene (DBT) as a sole source of sulfur. Strain SY1 could utilize a wide range of organic and inorganic sulfur compounds, such as DBT sulfone, dimethyl sulfide, dimethyl sulfoxide, dimethyl sulfone, CS 2 , FeS 2 , and even elemental sulfur. Strain SY1 metabolized DBT to dibenzothiophene-5-oxide, DBT sulfone, and 2-hydroxybiphenyl, which was subsequently nitrated to produce at least two different hydroxynitrobiphenyls during cultivation. These metabolites were separated by silica gel column chromatography and identified by nuclear magnetic resonance, UV, and mass spectral techniques. Resting cells of SY1 desulfurized toluenesulfonic acid and released sulfite anion. On the basis of these results, a new DBT degradation pathway is proposed

Molecular interaction between Methylobacterium extorquens and seedlings: growth promotion, methanol consumption, and localization of the methanol emission site.

Science.gov (United States)

Abanda-Nkpwatt, Daniel; Müsch, Martina; Tschiersch, Jochen; Boettner, Mewes; Schwab, Wilfried

2006-01-01

Four Methylobacterium extorquens strains were isolated from strawberry (Fragaria x ananassa cv. Elsanta) leaves, and one strain, called ME4, was tested for its ability to promote the growth of various plant seedlings. Seedling weight and shoot length of Nicotiana tabacum, Lycopersicon esculentum, Sinapis alba, and Fragaria vesca increased significantly in the presence of the pink-pigmented facultative methylotroph (PPFM), but the germination behaviour of seeds from six other plants was not affected. The cell-free supernatant of the bacterial culture stimulated germination, suggesting the production of a growth-promoting agent by the methylotroph. Methanol emitted from N. tabacum seedlings, as determined by proton-transfer-reaction mass spectrometry (PTR-MS), ranged from 0.4 to 0.7 ppbv (parts per billion by volume), while significantly lower levels (0.005 to 0.01 ppbv) of the volatile alcohol were measured when the seedlings were co-cultivated with M. extorquens ME4, demonstrating the consumption of the gaseous methanol by the bacteria. Additionally, by using cells of the methylotrophic yeast Pichia pastoris transformed with the pPICHS/GFP vector harbouring a methanol-sensitive promoter in combination with the green fluorescence protein (GFP) reporter gene, stomata were identified as the main source of the methanol emission on tobacco cotyledons. Methylobacterium extorquens strains can nourish themselves using the methanol released by the stomata and release an agent promoting the growth of the seedlings of some crop plants.

Bioconversion of methanol to value-added mevalonate by engineered Methylobacterium extorquens AM1 containing an optimized mevalonate pathway.

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Zhu, Wen-Liang; Cui, Jin-Yu; Cui, Lan-Yu; Liang, Wei-Fan; Yang, Song; Zhang, Chong; Xing, Xin-Hui

2016-03-01

Methylotrophic biosynthesis using methanol as a feedstock is a promising and attractive method to solve the over-dependence of the bioindustry on sugar feedstocks derived from grains that are used for food. In this study, we introduced and engineered the mevalonate pathway into Methylobacterium extorquens AM1 to achieve high mevalonate production from methanol, which could be a platform for terpenoid synthesis. We first constructed a natural operon (MVE) harboring the mvaS and mvaE genes from Enterococcus faecalis as well as an artificial operon (MVH) harboring the hmgcs1 gene from Blattella germanica and the tchmgr gene from Trypanosoma cruzi that encoded enzymes with the highest reported activities. We achieved mevalonate titers of 56 and 66 mg/L, respectively, in flask cultivation. Introduction of the phaA gene from Ralstonia eutropha into the operon MVH increased the mevalonate titer to 180 mg/L, 3.2-fold higher than that of the natural operon MVE. Further modification of the expression level of the phaA gene by regulating the strength of the ribosomal binding site resulted in an additional 20 % increase in mevalonate production to 215 mg/L. A fed-batch fermentation of the best-engineered strain yielded a mevalonate titer of 2.22 g/L, which was equivalent to an overall yield and productivity of 28.4 mg mevalonate/g methanol and 7.16 mg/L/h, respectively. The production of mevalonate from methanol, which is the initial, but critical step linking methanol with valuable terpenoids via methylotrophic biosynthesis, represents a proof of concept for pathway engineering in M. extorquens AM1.

A quantitative study of methanol/sorbitol co-feeding process of a Pichia pastoris Mut+/pAOX1-lacZ strain

Science.gov (United States)

2013-01-01

Background One of the main challenges for heterologous protein production by the methylotrophic yeast Pichia pastoris at large-scale is related to its high oxygen demand. A promising solution is a co-feeding strategy based on a methanol/sorbitol mixture during the induction phase. Nonetheless, a deep understanding of the cellular physiology and the regulation of the AOX1 promoter, used to govern heterologous protein production, during this co-feeding strategy is still scarce. Results Transient continuous cultures with a dilution rate of 0.023 h-1 at 25°C were performed to quantitatively assess the benefits of a methanol/sorbitol co-feeding process with a Mut+ strain in which the pAOX1-lacZ construct served as a reporter gene. Cell growth and metabolism, including O2 consumption together with CO2 and heat production were analyzed with regard to a linear change of methanol fraction in the mixed feeding media. In addition, the regulation of the promoter AOX1 was investigated by means of β-galactosidase measurements. Our results demonstrated that the cell-specific oxygen consumption (qO2) could be reduced by decreasing the methanol fraction in the feeding media. More interestingly, maximal β-galactosidase cell-specific activity (>7500 Miller unit) and thus, optimal pAOX1 induction, was achieved and maintained in the range of 0.45 ~ 0.75 C-mol/C-mol of methanol fraction. In addition, the qO2 was reduced by 30% at most in those conditions. Based on a simplified metabolic network, metabolic flux analysis (MFA) was performed to quantify intracellular metabolic flux distributions during the transient continuous cultures, which further shed light on the advantages of methanol/sorbitol co-feeding process. Finally, our observations were further validated in fed-batch cultures. Conclusion This study brings quantitative insight into the co-feeding process, which provides valuable data for the control of methanol/sorbitol co-feeding, aiming at enhancing biomass and

Gastric vagus mediates immobilization-induced hypocalcemia in rats.

Science.gov (United States)

Ma, J; Aou, S; Matsui, H; Hori, T

1993-09-01

The involvement of the parasympathetic nervous system in the etiology of stress-induced hypocalcemia was investigated in the rat. Atropine methyl bromide (0.1 and 0.6 mg/kg ip) given 20 min before immobilization (IMB) was observed to suppress the induction of hypocalcemia in a dose-dependent manner. A vagotomy of the bilateral cervical trunks also abolished the IMB-induced hypocalcemia. A vagotomy on either the thyroid/parathyroid branches or the celiac branches had no effect on the IMB-induced hypocalcemia, but a vagotomy on the gastric branches completely abolished it. Pretreatment with either secretin (2 and 6 micrograms/kg ip), an inhibitor of gastrin release, or cimetidine (5 and 10 mg/kg ip), a histamine H2-receptor antagonist, diminished the IMB-induced hypocalcemia. The concentration of serum gastrin increased significantly during IMB. It is thus concluded that the decreased levels of plasma calcium caused by IMB are due to the activation of the vagus innervating the stomach. Gastrin and histamine are also involved as a consequence of the activation of the vagus.

Comparative genome analysis of the high pathogenicity Salmonella Typhimurium strain UK-1.

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Yingqin Luo

Full Text Available Salmonella enterica serovar Typhimurium, a gram-negative facultative rod-shaped bacterium causing salmonellosis and foodborne disease, is one of the most common isolated Salmonella serovars in both developed and developing nations. Several S. Typhimurium genomes have been completed and many more genome-sequencing projects are underway. Comparative genome analysis of the multiple strains leads to a better understanding of the evolution of S. Typhimurium and its pathogenesis. S. Typhimurium strain UK-1 (belongs to phage type 1 is highly virulent when orally administered to mice and chickens and efficiently colonizes lymphoid tissues of these species. These characteristics make this strain a good choice for use in vaccine development. In fact, UK-1 has been used as the parent strain for a number of nonrecombinant and recombinant vaccine strains, including several commercial vaccines for poultry. In this study, we conducted a thorough comparative genome analysis of the UK-1 strain with other S. Typhimurium strains and examined the phenotypic impact of several genomic differences. Whole genomic comparison highlights an extremely close relationship between the UK-1 strain and other S. Typhimurium strains; however, many interesting genetic and genomic variations specific to UK-1 were explored. In particular, the deletion of a UK-1-specific gene that is highly similar to the gene encoding the T3SS effector protein NleC exhibited a significant decrease in oral virulence in BALB/c mice. The complete genetic complements in UK-1, especially those elements that contribute to virulence or aid in determining the diversity within bacterial species, provide key information in evaluating the functional characterization of important genetic determinants and for development of vaccines.

Clostridium difficile outbreak caused by NAP1/BI/027 strain and non-027 strains in a Mexican hospital

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Rayo Morfin-Otero

2016-01-01

Conclusions: C. difficile NAP1/BI/027 strain and non-027 strains are established pathogens in our hospital. Accordingly, surveillance of C. difficile infections is now part of our nosocomial prevention program.

The Effect of Nitrogen Enrichment on C1-Cycling Microorganisms and Methane Flux in Salt Marsh Sediments

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Irina Catherine Irvine

2012-03-01

Full Text Available Methane (CH4 flux from ecosystems is driven by C1-cycling microorganisms – the methanogens and the methylotrophs. Little is understood about what regulates these communities, complicating predictions about how global change drivers such as nitrogen enrichment will affect methane cycling. Using a nitrogen addition gradient experiment in three Southern California salt marshes, we show that sediment CH4 flux increased linearly with increasing nitrogen addition (1.23 µg CH4 m-2 d-1 for each g N m-2 yr-1 applied after seven months of fertilization. To test the reason behind this increased CH4 flux, we conducted a microcosm experiment altering both nitrogen and carbon availability under aerobic and anaerobic conditions. Methanogenesis appeared to be both nitrogen and carbon (acetate limited. N and C each increased methanogenesis by 18%, and together by 44%. In contrast, methanotrophy was stimulated by carbon (methane addition (830%, but was unchanged by nitrogen addition. Sequence analysis of the sediment methylotroph community with the methanol dehydrogenase gene (mxaF revealed three distinct clades that fall outside of known lineages. However, in agreement with the microcosm results, methylotroph abundance (assayed by qPCR and composition (assayed by T-RFLP did not vary across the experimental nitrogen gradient in the field. Together, these results suggest that nitrogen enrichment to salt marsh sediments increases methane flux by stimulating the methanogen community.

Expression and characterization of the antimicrobial peptide ABP-dHC-cecropin A in the methylotrophic yeast Pichia pastoris.

Science.gov (United States)

Sang, Ming; Wei, Hui; Zhang, Jiaxin; Wei, Zhiheng; Wu, Xiaolong; Chen, Yan; Zhuge, Qiang

2017-12-01

ABP-dHC-cecropin A is a linear cationic peptide that exhibits antimicrobial properties. To explore a new approach for expression of ABP-dHC-cecropin A using the methylotrophic yeast Pichia pastoris, we cloned the ABP-dHC-cecropin A gene into the vector pPICZαA. The SacI-linearized plasmid pPICZαA-ABP-dHC-cecropin A was then transformed into P. pastoris GS115 by electroporation. Expression was induced after a 96-h incubation with 0.5% methanol at 20 °C in a culture supplied with 2% casamino acids to avoid proteolysis. Under these conditions, approximately 48 mg of ABP-dHC-cecropin A was secreted into 1L (4 × 250-mL)of medium. Recombinant ABP-dHC-cecropin A was purified using size-exclusion chromatography, and 21 mg of pure active ABP-dHC-cecropin A was obtained from 1L (4 × 250-mL)of culture. Electrophoresis on 4-20% gradient gels indicated that recombinant ABP-dHC-cecropin A was secreted as a protein approximately 4 kDa in size. Recombinant ABP-dHC-cecropin A was successfully expressed, as the product displayed antibacterial and antifungal activities (based on an antibacterial assay, scanning electron microscopy, and antifungal assay) indistinguishable from those of the synthesized protein. Copyright © 2017 Elsevier Inc. All rights reserved.

A quantitative study of methanol/sorbitol co-feeding process of a Pichia pastoris Mut⁺/pAOX1-lacZ strain.

Science.gov (United States)

Niu, Hongxing; Jost, Laurent; Pirlot, Nathalie; Sassi, Hosni; Daukandt, Marc; Rodriguez, Christian; Fickers, Patrick

2013-04-08

One of the main challenges for heterologous protein production by the methylotrophic yeast Pichia pastoris at large-scale is related to its high oxygen demand. A promising solution is a co-feeding strategy based on a methanol/sorbitol mixture during the induction phase. Nonetheless, a deep understanding of the cellular physiology and the regulation of the AOX1 promoter, used to govern heterologous protein production, during this co-feeding strategy is still scarce. Transient continuous cultures with a dilution rate of 0.023 h(-1) at 25°C were performed to quantitatively assess the benefits of a methanol/sorbitol co-feeding process with a Mut+ strain in which the pAOX1-lacZ construct served as a reporter gene. Cell growth and metabolism, including O2 consumption together with CO2 and heat production were analyzed with regard to a linear change of methanol fraction in the mixed feeding media. In addition, the regulation of the promoter AOX1 was investigated by means of β-galactosidase measurements. Our results demonstrated that the cell-specific oxygen consumption (qO2) could be reduced by decreasing the methanol fraction in the feeding media. More interestingly, maximal β-galactosidase cell-specific activity (>7500 Miller unit) and thus, optimal pAOX1 induction, was achieved and maintained in the range of 0.45 ~ 0.75 C-mol/C-mol of methanol fraction. In addition, the qO2 was reduced by 30% at most in those conditions. Based on a simplified metabolic network, metabolic flux analysis (MFA) was performed to quantify intracellular metabolic flux distributions during the transient continuous cultures, which further shed light on the advantages of methanol/sorbitol co-feeding process. Finally, our observations were further validated in fed-batch cultures. This study brings quantitative insight into the co-feeding process, which provides valuable data for the control of methanol/sorbitol co-feeding, aiming at enhancing biomass and heterologous protein productivities

Degradation of 1,2-Dibromoethane by Mycobacterium sp. Strain GP1

NARCIS (Netherlands)

Poelarends, Gerrit J.; van Hylckama Vlieg, Johannes; Marchesi, Julian R.; Freitas dos Santos, Luisa M.; Janssen, Dick B.

The newly isolated bacterial strain GP1 can utilize 1,2-dibromoethane as the sole carbon and energy source. On the basis of 16S rRNA gene sequence analysis, the organism was identified as a member of the subgroup which contains the fast-growing mycobacteria, The first step in 1,2-dibromoethane

Characterization of glycoprotein C of HSZP strain of herpes simplex virus 1

NARCIS (Netherlands)

Oravcova, [No Value; Kudelova, M; Mlcuchova, J; Matis, J; Bystricka, M; Westra, DF; Welling-Wester, S; Rajcani, J

Sequences of UL44 genes of strains HSZP, KOS and 17 of herpes simplex virus 1 (HSV-1) were determined and the amino acid sequences of corresponding glycoproteins (gC) were deduced. In comparison with the 17 strain, the HSZP strain showed specific changes in 3 nucleotides and in 2 amino acids (aa 139

An empirical test of the information-motivation-behavioral skills model of ART adherence in a sample of HIV-positive persons primarily in out-of-HIV-care settings.

Science.gov (United States)

Horvath, Keith J; Smolenski, Derek; Amico, K Rivet

2014-02-01

The current body of evidence supporting the Information-Motivation-Behavioral Skills (IMB) model of antiretroviral therapy (ART) adherence rests exclusively on data collected from people living with HIV (PLWH) at point-of-HIV-care services. The aims of this study were to: (1) determine if the IMB model is a useful predictive model of ART adherence among PLWH who were primarily recruited in out-of-HIV-care settings; and (2) assess whether the theorized associations between IMB model constructs and adherence persist in the presence of depression and current drug use. PLWH (n = 312) responding to a one-time online survey completed the Life Windows IMB-ART-Adherence Questionnaire, and demographic, depression (CES-D 10), and drug use items. Path models were used to assess the fit of a saturated versus fully mediated IMB model of adherence and examined for moderating effects of depression and current drug use. Participants were on average 43 years of age, had been living with HIV for 9 or more years, and mostly male (84.0%), Caucasian (68.8%), and gay-identified (74.8%). The a priori measurement models for information and behavioral skills did not have acceptable fit to the data and were modified accordingly. Using the revised IMB scales, IMB constructs were associated with adherence as predicted by the theory in all but one model (i.e., the IMB model operated as predicted among nondrug users and those with and without depression). Among drug users, information exerted a direct effect on adherence but was not significantly associated with behavioral skills. Results of this study suggest that the fully or partially mediated IMB model is supported for use with samples of PLWH recruited primarily out-of-HIV-care service settings and is robust in the presence of depression and drug use.

Complete genome sequence of Rhodospirillum rubrum type strain (S1).

Science.gov (United States)

Munk, A Christine; Copeland, Alex; Lucas, Susan; Lapidus, Alla; Del Rio, Tijana Glavina; Barry, Kerrie; Detter, John C; Hammon, Nancy; Israni, Sanjay; Pitluck, Sam; Brettin, Thomas; Bruce, David; Han, Cliff; Tapia, Roxanne; Gilna, Paul; Schmutz, Jeremy; Larimer, Frank; Land, Miriam; Kyrpides, Nikos C; Mavromatis, Konstantinos; Richardson, Paul; Rohde, Manfred; Göker, Markus; Klenk, Hans-Peter; Zhang, Yaoping; Roberts, Gary P; Reslewic, Susan; Schwartz, David C

2011-07-01

Rhodospirillum rubrum (Esmarch 1887) Molisch 1907 is the type species of the genus Rhodospirillum, which is the type genus of the family Rhodospirillaceae in the class Alphaproteobacteria. The species is of special interest because it is an anoxygenic phototroph that produces extracellular elemental sulfur (instead of oxygen) while harvesting light. It contains one of the most simple photosynthetic systems currently known, lacking light harvesting complex 2. Strain S1(T) can grow on carbon monoxide as sole energy source. With currently over 1,750 PubMed entries, R. rubrum is one of the most intensively studied microbial species, in particular for physiological and genetic studies. Next to R. centenum strain SW, the genome sequence of strain S1(T) is only the second genome of a member of the genus Rhodospirillum to be published, but the first type strain genome from the genus. The 4,352,825 bp long chromosome and 53,732 bp plasmid with a total of 3,850 protein-coding and 83 RNA genes were sequenced as part of the DOE Joint Genome Institute Program DOEM 2002.

241-SY-101 strain concentration factor development via nonlinear analysis. Volume 1 of 1

International Nuclear Information System (INIS)

1997-01-01

The 241-SY-101 waste storage tank at the Hanford-Site has been known to accumulate and release significant quantities of hydrogen gas. An analysis was performed to assess the tank's structural integrity when subjected to postulated hydrogen deflagration loads. The analysis addressed many nonlinearities and appealed to a strain-based failure criteria. The model used to predict the global response of the tank was not refined enough to confidently predict local peak strains. Strain concentration factors were applied at structural discontinuities that were based on steel-lined reinforced-concrete containment studies. The discontinuities included large penetrations, small penetrations, springline geometries, stud/liner connections, and the 1/2 inch to 3/8 inch liner thickness transition. The only tank specific strain concentration factor applied in the evaluation was for the 1/2 inch to 3/8 inch liner thickness change in the dome. Review of the tank drawings reveals the possibility that a 4 inches Sch. 40 pipe penetrates the dome thickness transition region. It is not obvious how to combine the strain concentration factors for a small penetration with that of a thickness transition to arrive at a composite strain concentration factor. It is the goal of this effort to make an approximate determination of the relative significance of the 4 inch penetration and the 1/2 inch to 3/8 inch thickness transition in the 241-SY-101 dome geometry. This is accomplished by performing a parametric study with three general finite-element models. The first represents the thickness transition only, the second represents a 4 inch penetration only, and the third combines the thickness transition with a penetration model

Full Genome Characterization of Novel DS-1-Like G8P[8] Rotavirus Strains that Have Emerged in Thailand: Reassortment of Bovine and Human Rotavirus Gene Segments in Emerging DS-1-Like Intergenogroup Reassortant Strains.

Directory of Open Access Journals (Sweden)

Ratana Tacharoenmuang

Full Text Available The emergence and rapid spread of unusual DS-1-like intergenogroup reassortant rotavirus strains have been recently reported in Asia, Australia, and Europe. During rotavirus surveillance in Thailand in 2013-2014, novel DS-1-like intergenogroup reassortant strains having G8P[8] genotypes (i.e., strains KKL-17, PCB-79, PCB-84, PCB-85, PCB-103, SKT-107, SWL-12, NP-130, PCB-656, SKT-457, SSKT-269, and SSL-55 were identified in stool samples from hospitalized children with severe diarrhea. In this study, we determined and characterized the complete genomes of these 12 strains (seven strains, KKL-17, PCB-79, PCB-84, PCB-85, PCB-103, SKT-107, and SWL-12, found in 2013 (2013 strains, and five, NP-130, PCB-656, SKT-457, SSKT-269, and SSL-55, in 2014 (2014 strains. On full genomic analysis, all 12 strains showed a unique genotype constellation comprising a mixture of genogroup 1 and 2 genes: G8-P[8]-I2-R2-C2-M2-A2-N2-T2-E2-H2. With the exception of the G genotype, the unique genotype constellation of the 12 strains (P[8]-I2-R2-C2-M2-A2-N2-T2-E2-H2 was found to be shared with DS-1-like intergenogroup reassortant strains. On phylogenetic analysis, six of the 11 genes of the 2013 strains (VP4, VP2, VP3, NSP1, NSP3, and NSP5 appeared to have originated from DS-1-like intergenogroup reassortant strains, while the remaining four (VP7, VP6, VP1, and NSP2 and one (NSP4 gene appeared to be of bovine and human origin, respectively. Thus, the 2013 strains appeared to be reassortant strains as to DS-1-like intergenogroup reassortant, bovine, bovine-like human, and/or human rotaviruses. On the other hand, five of the 11 genes of the 2014 strains (VP4, VP2, VP3, NSP1, and NSP3 appeared to have originated from DS-1-like intergenogroup reassortant strains, while three (VP7, VP1, and NSP2 and one (NSP4 were assumed to be of bovine and human origin, respectively. Notably, the remaining two genes, VP6 and NSP5, of the 2014 strains appeared to have originated from locally

Pichia pastoris Mut(S) strains are prone to misincorporation of O-methyl-L-homoserine at methionine residues when methanol is used as the sole carbon source.

Science.gov (United States)

Schotte, Peter; Dewerte, Isabelle; De Groeve, Manu; De Keyser, Saskia; De Brabandere, Veronique; Stanssens, Patrick

2016-06-07

Over the last few decades the methylotrophic yeast Pichia pastoris has become a popular host for a wide range of products such as vaccines and therapeutic proteins. Several P. pastoris engineered strains and mutants have been developed to improve the performance of the expression system. Yield and quality of a recombinant product are important parameters to monitor during the host selection and development process but little information is published regarding quality differences of a product produced by different P. pastoris strains. We compared titer and quality of several Nanobodies(®) produced in wild type and Mut(S) strains. Titer in fed-batch fermentation was comparable between all strains for each Nanobody but a significant difference in quality was observed. Nanobodies expressed in Mut(S) strains contained a product variant with a Δ-16 Da mass difference that was not observed in wild type strains. This variant showed substitution of methionine residues due to misincorporation of O-methyl-L-homoserine, also called methoxine. Methoxine is likely synthesized by the enzymatic action of O-acetyl homoserine sulfhydrylase and we confirmed that Nanobodies produced in the corresponding knock-out strain contained no methoxine variants. We could show the incorporation of methoxine during biosynthesis by its addition to the culture medium. We showed that misincorporation of methoxine occurs particularly in P. pastoris Mut(S) strains. This reduction in product quality could outweigh the advantages of using Mut strains, such as lower oxygen and methanol demand, heat formation and in some cases improved expression. Methoxine incorporation in recombinant proteins is likely to occur when an excess of methanol is present during fermentation but can be avoided when the methanol feed rate protocol is carefully designed.

Genes related to antioxidant metabolism are involved in Methylobacterium mesophilicum-soybean interaction.

Science.gov (United States)

Araújo, Welington Luiz; Santos, Daiene Souza; Dini-Andreote, Francisco; Salgueiro-Londoño, Jennifer Katherine; Camargo-Neves, Aline Aparecida; Andreote, Fernando Dini; Dourado, Manuella Nóbrega

2015-10-01

The genus Methylobacterium is composed of pink-pigmented methylotrophic bacterial species that are widespread in natural environments, such as soils, stream water and plants. When in association with plants, this genus colonizes the host plant epiphytically and/or endophytically. This association is known to promote plant growth, induce plant systemic resistance and inhibit plant infection by phytopathogens. In the present study, we focused on evaluating the colonization of soybean seedling-roots by Methylobacterium mesophilicum strain SR1.6/6. We focused on the identification of the key genes involved in the initial step of soybean colonization by methylotrophic bacteria, which includes the plant exudate recognition and adaptation by planktonic bacteria. Visualization by scanning electron microscopy revealed that M. mesophilicum SR1.6/6 colonizes soybean roots surface effectively at 48 h after inoculation, suggesting a mechanism for root recognition and adaptation before this period. The colonization proceeds by the development of a mature biofilm on roots at 96 h after inoculation. Transcriptomic analysis of the planktonic bacteria (with plant) revealed the expression of several genes involved in membrane transport, thus confirming an initial metabolic activation of bacterial responses when in the presence of plant root exudates. Moreover, antioxidant genes were mostly expressed during the interaction with the plant exudates. Further evaluation of stress- and methylotrophic-related genes expression by qPCR showed that glutathione peroxidase and glutathione synthetase genes were up-regulated during the Methylobacterium-soybean interaction. These findings support that glutathione (GSH) is potentially a key molecule involved in cellular detoxification during plant root colonization. In addition to methylotrophic metabolism, antioxidant genes, mainly glutathione-related genes, play a key role during soybean exudate recognition and adaptation, the first step in

Duplex PCR for differentiation of the vaccine strain Brucella suis S2 and B. suis biovar 1 from other strains of Brucella spp.

Science.gov (United States)

Nan, Wenlong; Tan, Pengfei; Wang, Yong; Xu, Zouliang; Mao, Kairong; Peng, Daxin; Chen, Yiping

2014-09-01

Immunisation with attenuated Brucella spp. vaccines prevents brucellosis, but may also interfere with diagnosis. In this study, a duplex PCR was developed to distinguish Brucella suis vaccine strain S2 from field strains of B. suis biovar 1 and other Brucella spp. The PCR detected 60 fg genomic DNA of B. suis S2 or biovar 1 field strains and was able to distinguish B. suis S2 and wild-type strains of B. suis biovar 1 among 76 field isolates representing all the common species and biovars, as well as four vaccine strains, of Brucella. Copyright © 2014 Elsevier Ltd. All rights reserved.

An optimal algorithm for configuring delivery options of a one-dimensional intensity-modulated beam

International Nuclear Information System (INIS)

Luan Shuang; Chen, Danny Z; Zhang, Li; Wu Xiaodong; Yu, Cedric X

2003-01-01

The problem of generating delivery options for one-dimensional intensity-modulated beams (1D IMBs) arises in intensity-modulated radiation therapy. In this paper, we present an algorithm with the optimal running time, based on the 'rightmost-preference' method, for generating all distinct delivery options for an arbitrary 1D IMB. The previously best known method for generating delivery options for a 1D IMB with N left leaf positions and N right leaf positions is a 'brute-force' solution, which first generates all N! possible combinations of the left and right leaf positions and then removes combinations that are not physically allowed delivery options. Compared with the brute-force method, our algorithm has several advantages: (1) our algorithm runs in an optimal time that is linearly proportional to the total number of distinct delivery options that it actually produces. Note that for a 1D IMB with multiple peaks, the total number of distinct delivery options in general tends to be considerably smaller than the worst case N!. (2) Our algorithm can be adapted to generating delivery options subject to additional constraints such as the 'minimum leaf separation' constraint. (3) Our algorithm can also be used to generate random subsets of delivery options; this feature is especially useful when the 1D IMBs in question have too many delivery options for a computer to store and process. The key idea of our method is that we impose an order on how left leaf positions should be paired with right leaf positions. Experiments indicated that our rightmost-preference algorithm runs dramatically faster than the brute-force algorithm. This implies that our algorithm can handle 1D IMBs whose sizes are substantially larger than those handled by the brute-force method. Applications of our algorithm in therapeutic techniques such as intensity-modulated arc therapy and 2D modulations are also discussed

Development of a genetic sexing strain in Bactrocera carambolae (Diptera: Tephritidae) by introgression of sex sorting components from B. dorsalis, Salaya1 strain.

Science.gov (United States)

Isasawin, Siriwan; Aketarawong, Nidchaya; Lertsiri, Sittiwat; Thanaphum, Sujinda

2014-01-01

The carambola fruit fly, Bactrocera carambolae Drew & Hancock is a high profile key pest that is widely distributed in the southwestern ASEAN region. In addition, it has trans-continentally invaded Suriname, where it has been expanding east and southward since 1975. This fruit fly belongs to Bactrocera dorsalis species complex. The development and application of a genetic sexing strain (Salaya1) of B. dorsalis sensu stricto (s.s.) (Hendel) for the sterile insect technique (SIT) has improved the fruit fly control. However, matings between B. dorsalis s.s. and B. carambolae are incompatible, which hinder the application of the Salaya1 strain to control the carambola fruit fly. To solve this problem, we introduced genetic sexing components from the Salaya1 strain into the B. carambolae genome by interspecific hybridization. Morphological characteristics, mating competitiveness, male pheromone profiles, and genetic relationships revealed consistencies that helped to distinguish Salaya1 and B. carambolae strains. A Y-autosome translocation linking the dominant wild-type allele of white pupae gene and a free autosome carrying a recessive white pupae homologue from the Salaya1 strain were introgressed into the gene pool of B. carambolae. A panel of Y-pseudo-linked microsatellite loci of the Salaya1 strain served as markers for the introgression experiments. This resulted in a newly derived genetic sexing strain called Salaya5, with morphological characteristics corresponding to B. carambolae. The rectal gland pheromone profile of Salaya5 males also contained a distinctive component of B. carambolae. Microsatellite DNA analyses confirmed the close genetic relationships between the Salaya5 strain and wild B. carambolae populations. Further experiments showed that the sterile males of Salaya5 can compete with wild males for mating with wild females in field cage conditions. Introgression of sex sorting components from the Salaya1 strain to a closely related B. carambolae

Degradation of 4-fluorophenol by Arthrobacter sp strain IF1

NARCIS (Netherlands)

Ferreira, Maria Isabel M.; Marchesi, Julian R.; Janssen, Dick B.

A Gram-positive bacterial strain capable of aerobic biodegradation of 4-fluorophenol (4-FP) as the sole source of carbon and energy was isolated by selective enrichment from soil samples collected near an industrial site. The organism, designated strain IF1, was identified as a member of the genus

Activation of the oxidative stress regulator PpYap1 through conserved cysteine residues during methanol metabolism in the yeast Pichia pastoris.

Science.gov (United States)

Yano, Taisuke; Yurimoto, Hiroya; Sakai, Yasuyoshi

2009-06-01

The methylotrophic yeast Pichia pastoris can grow on methanol as sole source of carbon and energy. The first reaction in yeast methanol metabolism, catalyzed by an abundant peroxisomal enzyme, alcohol oxidase, generates high levels of H(2)O(2), but the oxidative stress response during methanol metabolism has not been elucidated. In this study, we isolated the Yap1 homolog of P. pastoris (PpYap1) and analyzed the properties of a PpYAP1-disruption strain. The PpYap1 transcription factor is activated after exposure to various reactive agents, and therefore functions as a regulator of the redox system in P. pastoris. We have also identified PpGPX1, the unique glutathione peroxidase-encoding gene in P. pastoris whose expression is induced by PpYap1. PpGpx1, but not the ScTsa1 or SpTpx1 homolog PpTsa1, functions as a H(2)O(2) sensor and activates PpYap1. This study is the first demonstration of a yeast Yap1 family protein activated during conventional metabolism.

Strain and strain-release engineering at epitaxial SiGe islands on Si(0 0 1) for microelectronic applications

International Nuclear Information System (INIS)

Vastola, G.; Marzegalli, A.; Montalenti, F.; Miglio, Leo

2009-01-01

We report original finite element method simulations of the strain components at nanometric GeSi island on Si(0 0 1), for realistic shape, sizes and average composition, discussing the main mechanisms acting in the misfit strain relaxation. The tensile strain induced in a 30 nm Si capping layer and the one upon removing the island, after fixing the top part of the Si layer, is discussed in view of application as a field effect transistor channel, with high career mobility induced by the lattice deformation. The large shear components obtained for steeper island morphologies are predicted to be particularly performing, especially in comparison to one another strained-silicon configuration (totally top-down originated), recently developed by IBM corporation.

Co-Consumption of Methanol and Succinate by Methylobacterium extorquens AM1

Science.gov (United States)

Peyraud, Rémi; Kiefer, Patrick; Christen, Philipp; Portais, Jean-Charles; Vorholt, Julia A.

2012-01-01

Methylobacterium extorquens AM1 is a facultative methylotrophic Alphaproteobacterium and has been subject to intense study under pure methylotrophic as well as pure heterotrophic growth conditions in the past. Here, we investigated the metabolism of M. extorquens AM1 under mixed substrate conditions, i.e., in the presence of methanol plus succinate. We found that both substrates were co-consumed, and the carbon conversion was two-thirds from succinate and one-third from methanol relative to mol carbon. 13C-methanol labeling and liquid chromatography mass spectrometry analyses revealed the different fates of the carbon from the two substrates. Methanol was primarily oxidized to CO2 for energy generation. However, a portion of the methanol entered biosynthetic reactions via reactions specific to the one-carbon carrier tetrahydrofolate. In contrast, succinate was primarily used to provide precursor metabolites for bulk biomass production. This work opens new perspectives on the role of methylotrophy when substrates are simultaneously available, a situation prevailing under environmental conditions. PMID:23133625

Genomic Comparison among Lethal Invasive Strains of Streptococcus pyogenes Serotype M1

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Gabriel R. Fernandes

2017-10-01

Full Text Available Streptococcus pyogenes, also known as group A Streptococcus (GAS, is a human pathogen that causes diverse human diseases including streptococcal toxic shock syndrome (STSS. A GAS outbreak occurred in Brasilia, Brazil, during the second half of the year 2011, causing 26 deaths. Whole genome sequencing was performed using Illumina platform. The sequences were assembled and genes were predicted for comparative analysis with emm type 1 strains: MGAS5005 and M1 GAS. Genomics comparison revealed one of the invasive strains that differ from others isolates and from emm 1 reference genomes. Also, the new invasive strain showed differences in the content of virulence factors compared to other isolated in the same outbreak. The evolution of contemporary GAS strains is strongly associated with horizontal gene transfer. This is the first genomic study of a Streptococcal emm 1 outbreak in Brazil, and revealed the rapid bacterial evolution leading to new clones. The emergence of new invasive strains can be a consequence of the injudicious use of antibiotics in Brazil during the past decades.

A brief information–motivation–behavioral skills intervention to promote human papillomavirus vaccination among college-aged women

Directory of Open Access Journals (Sweden)

Perez GK

2016-10-01

Full Text Available Giselle K Perez,1 Dean G Cruess,2 Nicole M Strauss,3 1Department of Psychiatry, Massachusetts General Hospital, Boston, MA, 2Department of Psychology, University of Connecticut, Storrs, CT, 3Mongan Institute for Health Policy, Massachusetts General Hospital, Boston, MA, USA Background: Human papillomavirus (HPV is prevalent among college-aged women. Although HPV vaccines decrease women’s risk for cervical cancer, the vaccination rates remain inadequate.  Objective: This study explored the utility of an information–motivation–behavioral skills (IMB intervention in promoting HPV vaccination knowledge, motivation, and intentions among college-aged women. Methods: In Spring/Fall 2012, 62 participants were randomly assigned to a single-session intervention or attention control and were assessed baseline, post-intervention, and at 1 month. Results: The participants demonstrated adequate baseline vaccine knowledge, low HPV/cancer knowledge, and ambivalence about the vaccination. Post-intervention, the IMB arm demonstrated increased HPV/cancer and vaccination knowledge, motivation, and intentions. There were no group differences in vaccination at 1 month; however, the odds of wanting to get vaccinated increased sevenfold in the IMB arm. Conclusion: These results provide preliminary support for an IMB-based intervention in increasing vaccination knowledge, motivation, and intentions among at-risk women. Future research examining the efficacy of longer trials with larger, diverse populations is warranted. Keywords: human papillomavirus, HPV, vaccination, cervical cancer, Gardasil, IMB

76 FR 65640 - New Standards for Domestic Mailing Services

Science.gov (United States)

2011-10-24

...: Proposed prices will be available under Docket Number(s) R2012-3 on the Postal Regulatory Commission's Web... and to replace it with ``IMb\\TM\\ Tracing,'' which will provide scan data similar to that provided... IMb Tracing [Delete the current text of 14.1 through 14.4 and replace with the following:] 14.1 Basic...

Simultaneous removal of chlorothalonil and nitrate by Bacillus cereus strain NS1

International Nuclear Information System (INIS)

Zhang Yiqiang; Lu Jianhang; Wu Laosheng; Chang, Andrew; Frankenberger, William T.

2007-01-01

Elevated NO 3 - and chlorothalonil (CTN) have been found in production nursery recycling ponds. Bacillus cereus strain NS1 isolated from nursery recycling pond sediment was assessed for its ability to reduce NO 3 - and degrade CTN in a mineral medium. The results showed that the efficiency of NO 3 - reduction and CTN degradation by B. cereus strain NS1 were related to the nature of organic carbon sources added to the medium. In the medium amended with 100 mg/L yeast extract, 86% of NO 3 - (100 mg/L) and 99% of CTN (78 μg/L) were simultaneously removed by B. cereus strain NS1 during the first day of the experiment. It took 6 days for the removal of 82-93% of NO 3 - and 87-91% of CTN in the media containing glucose and acetate. B. cereus strain NS1 needed organic carbon as energy sources and electron donors to respire NO 3 - , and simultaneously degrade CTN. These results suggest that B. cereus strain NS1 may have great potential to remediate NO 3 - and CTN contaminated water in nursery recycling ponds

Diversification of the vacAs1m1 and vacAs2m2 strains of Helicobacter pylori in Meriones unguiculatus

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Sandra Mendoza Elizalde

2016-11-01

Full Text Available The bacterium Helicobacter pylori exhibits great genetic diversity, and the pathogenic roles of its virulence factors have been widely studied. However, the evolutionary dynamics of H. pylori strains during stomach colonization are not well characterized. Here, we analyzed the microevolutionary dynamics of the toxigenic strain vacAs1m1, the non-toxigenic strain vacAs2m2, and a combination of both strains in an animal model over time. Meriones unguiculatus were inoculated with the following bacteria: group 1–toxigenic strain vacAs1m1/cagA+/cagE+/babA2+; ST181, group 2–non-toxigenic strain vacAs2m2/ cagA+/ cagE+/ babA2+; ST2901, and group 3–both strains. The gerbils were euthanized at different time points (3, 6, 12 and 18 months. In group 1, genetic alterations were observed at 6 and 12 months. With the combination of both strains, group 3 also exhibited genetic alterations at 3 and 18 months; moreover, a chimera, vacA m1-m2, was detected. Additionally, four new sequence types (STs were reported in the PubMLST database for H. pylori. Synonymous and non-synonymous mutations were analyzed and associated with alterations in amino acids. Microevolutionary analysis of the STs (PHYLOViZ identified in each group revealed many mutational changes in the toxigenic (vacAs1m1 and non-toxigenic (vacAs2m2 strains. Phylogenetic assessments (eBURST did not reveal clonal complexes. Our findings indicate that the toxigenic strain, vacAs1m1, and a combination of toxigenic and non-toxigenic strains acquired genetic material by recombination. The allelic combination, vacAs2m1, displayed the best adaptation in the animal model over time, and a chimera, m1-m2, was also identified, which confirmed previous reports.

Identification and genetic characterization of unique HIV-1 A1/C recombinant strain in South Africa.

Science.gov (United States)

Musyoki, Andrew M; Rakgole, Johnny N; Selabe, Gloria; Mphahlele, Jeffrey

2015-03-01

HIV isolates from South Africa are predominantly subtype C. Sporadic isolation of non-C strains has been reported mainly in cosmopolitan cities. HIV isolate j51 was recovered from a rural South African heterosexual female aged 51 years. Near full length amplification of the genome was attempted using PCR with primers targeting overlapping segments of the HIV genome. Analysis of 5593 bp (gag to vpu) at a bootstrap value greater than 70% found that all but the vpu gene was HIV-1 subtype A1. The vpu gene was assigned HIV-1 subtype C. The recombination breaking point was estimated at position 6035+/- 15 bp with reference to the beginning of the HXB2 reference strain. Isolate j51 revealed a unique genome constellation to previously reported recombinant strains with parental A/C backbones from South Africa though a common recombination with subtype C within the vpu gene. Identification of recombinant strains supports continued surveillance of HIV genetic diversity.

Cellulose hydrolysis by fungi. 1. Screening of cellulolytic strains

Energy Technology Data Exchange (ETDEWEB)

Roussos, S.; Raimbault, M. (Laboratoire de Microbiologie ORSTOM, Centre de Recherche IRCHA, 91 - Vert-le-Petit (France))

Trichoderma harzianum was selected from 30 strains of cellulolytic fungi with the aim of producing cellulases by solid state fermentation of lignocellulosic substrates. Special attention was paid to cellulase production (i. e. carboxymethylcellulase and filter paper activity), apical growth and conidia production. Under the conditions of our experiments, T. harzianum exhibited the highest cellulasic activities with 1,315 IU/I of carboxymethyl cellulose and 80 IU/l of filter paper activity. Apical growth (1 mm/h) and yield of conidial production (3.25 X 10/sup 10/ conidia/g of substrate dry weight) were also valuable characteristics of this strain in the use of solid state fermentation.

Transmission of Hemagglutinin D222G Mutant Strain of Pandemic (H1N1) 2009 Virus

Science.gov (United States)

Facchini, Marzia; Spagnolo, Domenico; De Marco, Maria A.; Calzoletti, Laura; Zanetti, Alessandro; Fumagalli, Roberto; Tanzi, Maria L.; Cassone, Antonio; Rezza, Giovanni; Donatelli, Isabella

2010-01-01

A pandemic (H1N1) 2009 virus strain carrying the D222G mutation was identified in a severely ill man and was transmitted to a household contact. Only mild illness developed in the contact, despite his obesity and diabetes. The isolated virus reacted fully with an antiserum against the pandemic vaccine strain. PMID:20409386

Large-scale bioreactor production of the herbicide-degrading Aminobacter sp. strain MSH1

DEFF Research Database (Denmark)

Schultz-Jensen, Nadja; Knudsen, Berith Elkær; Frkova, Zuzana

2014-01-01

The Aminobacter sp. strain MSH1 has potential for pesticide bioremediation because it degrades the herbicide metabolite 2,6-dichlorobenzamide (BAM). Production of the BAM-degrading bacterium using aerobic bioreactor fermentation was investigated. A mineral salt medium limited for carbon and with ......The Aminobacter sp. strain MSH1 has potential for pesticide bioremediation because it degrades the herbicide metabolite 2,6-dichlorobenzamide (BAM). Production of the BAM-degrading bacterium using aerobic bioreactor fermentation was investigated. A mineral salt medium limited for carbon...... and with an element composition similar to the strain was generated. The optimal pH and temperature for strain growth were determined using shaker flasks and verified in bioreactors. Glucose, fructose, and glycerol were suitable carbon sources for MSH1 (μ =0.1 h−1); slower growth was observed on succinate and acetic...... acid (μ =0.01 h−1). Standard conditions for growth of theMSH1 strain were defined at pH 7 and 25 °C, with glucose as the carbon source. In bioreactors (1 and 5 L), the specific growth rate of MSH1 increased from μ =0.1 h−1 on traditional mineral salt medium to μ =0.18 h−1 on the optimized mineral salt...

Optimisation of 1.3 μm strained-layer semiconductor lasers

International Nuclear Information System (INIS)

Pacey, C.

1999-03-01

The objectives of the research undertaken have been to investigate the properties of semiconductor lasers operating at around 1.3 μm. The aim of the investigation is to suggest modifications which give rise to improved operating characteristics especially in the high temperature (approaching 85 deg. C) range. The investigation can be divided into 2 sections: a theoretical approach and an experimental section. The theoretical study examined the performance of compressively strained InGaAsP/InP multiple quantum-well lasers emitting at 1.3 μm. in order to investigate the important factors and trends in the threshold current density and differential gain with strain, well width and well number. Structures with a fixed compressive strain of 1% but variable well width, and also with a fixed well width but variable strain from 0% to 1.4% have been considered. It has been found that there is little benefit to having compressive strains greater than 1%. For structures with a fixed 1% compressive strain and unstrained barriers, an optimum structure for lowest threshold current density and a high differential gain has been found to consist of six 35 A quantum-wells. In addition, compensated strain (CS) structures with compressive wells and tensile barriers have been examined. It is shown that the conduction band offset can be significantly increased and the valence band offset reduced in such structures, to give band-offset ratios comparable with aluminium based 1.3 μm devices. The gain calculations performed suggest that there is little degradation in the threshold carrier density or differential gain due to these alterations in the band offsets; and hence a better laser performance is expected due to a reduction in thermal leakage currents due to the improved electron confinement. The experimental study concentrates on looking at certain key design parameters to investigate their effect on the laser performance. These design parameters range from the number of quantum

Genetic relatedness of ciprofloxacin-resistant Shigella dysenteriae type 1 strains isolated in south Asia.

Science.gov (United States)

Talukder, Kaisar A; Khajanchi, Bijay K; Islam, M Aminul; Dutta, Dilip K; Islam, Zhahirul; Safa, Ashrafus; Khan, G Y; Alam, Khorshed; Hossain, M A; Malla, Sarala; Niyogi, S K; Rahman, Mustafizur; Watanabe, Haruo; Nair, G Balakrish; Sack, David A

2004-10-01

The aim of the present study was to determine the clonal relationships of ciprofloxacin-resistant Shigella dysenteriae type 1 strains isolated from south Asia, and S. dysenteriae 1 strains associated with epidemics in 1978, 1984 and 1994. The antimicrobial susceptibilities were examined by NCCLS methods. Molecular epidemiological characterization was performed by plasmid profiling, pulsed-field gel electrophoresis (PFGE) and mutation analysis of the quinolone resistance-determining region (QRDR) of gyrA by sequencing. Plasmid patterns of the current ciprofloxacin-resistant strains from India, Nepal and Bangladesh were very similar to those of the 1978, 1984 and 1994 epidemic isolates of S. dysenteriae 1, except for the presence of a new plasmid of approximately 2.6 MDa, which was found in one recent ciprofloxacin-resistant strain isolated in Bangladesh. PFGE analysis showed that the ciprofloxacin-resistant strains isolated in Bangladesh, India and Nepal belonged to a PFGE type (type A), which was possibly related to that of the 1984 and 1994 clone of S. dysenteriae 1, but different from 1978 epidemic strains. The current ciprofloxacin-resistant strains belong to five subtypes (A3-A7), all of which were found in India, but in Bangladesh and Nepal, only A3 existed. Mutation analysis of the QRDR of gyrA revealed that amino acid substitutions at positions 83 and 87 of ciprofloxacin-resistant strains isolated in Bangladesh were similar to those of the strains isolated in Nepal, but different (at position 87) from ciprofloxacin-resistant strains isolated in India. PFGE and mutation analysis of gyrA showed differences between the current ciprofloxacin-resistant S. dysenteriae 1 strains isolated in south Asia and those associated with epidemics in 1978, 1984 and 1994.

Membrane-aerated biofilm reactor for the removal of 1,2-dichloroethane by Pseudomonas sp strain DCA1

NARCIS (Netherlands)

Hage, J.C.; Houten, R.T.; Tramper, J.; Hartmans, S.

2004-01-01

A membrane-aerated biofilm reactor (MBR) with a biofilm of Pseudomonas sp. strain DCA1 was studied for the removal of 1,2-dichloroethane (DCA) from water. A hydrophobic membrane was used to create a barrier between the liquid and the gas phase. Inoculation of the MBR with cells of strain DCA1 grown

Draft genome sequences of Streptococcus bovis strains ATCC 33317 and JB1

Science.gov (United States)

We report the draft genome sequences of Streptococcus bovis type strain ATTC 33317 (CVM42251) isolated from cow dung and strain JB1 (CVM42252) isolated from a cow rumen in 1977. Strains were subjected to Next Generation sequencing and the genome sizes are approximately 2 MB and 2.2 MB, respectively....

Divergent strains of human T-lymphotropic virus type 1 (HTLV-1) within the Cosmopolitan subtype in Argentina.

Science.gov (United States)

Eirin, Maria E; Dilernia, Dario A; Berini, Carolina A; Jones, Leandro R; Pando, Maria A; Biglione, Mirna M

2008-10-01

HTLV-1 Cosmopolitan subtype Transcontinental subgroup A has been described among aboriginal communities from the northwest endemic area of Argentina. Moreover, Transcontinental subgroup A and the Japanese subgroup B were reported among blood donors from the nonendemic central region of the country. We carried out the first HTLV-1 phylogenetic study in individuals residing in Buenos Aires capital city. Phylogenetic analysis performed on the LTR region showed that all 44 new strains clustered within the Cosmopolitan subtype, with 42 (95.4%) belonging to Transcontinental subgroup A. Of them, 20 (45.5%) strains grouped in the large Latin American cluster and 4 (9.1%) in the small Latin American cluster. The majority of them belonged to individuals of nonblack origin, grouped with Amerindian strains. Three (6.8%) were closely related to South African references and two monophyletic clusters including only HIV/HTLV-1 coinfected individuals were observed. Interestingly, two (4.5%) new sequences (divergent strains) branched off from all five known Cosmopolitan subgroups in a well-supported clade. In summary, these findings show that HTLV-1 Cosmopolitan subtype Transcontinental subgroup A is infecting residents of Buenos Aires, a nonendemic area of Argentina, and confirm the introduction of divergent strains in the country.

Piezoresistance of Silicon and Strained Si0.9Ge0.1

DEFF Research Database (Denmark)

Richter, Jacob; Hansen, Ole; Larsen, A. Nylandsted

2005-01-01

We present experimentally obtained results of the piezoresistive effect in p-type silicon and strained Si0.9Ge0.1. Today, strained Si1-xGex is used for high speed electronic devices. This paper investigates if this area of use can be expanded to also cover piezoresistive micro electro mechanical...... systems (MEMS) devices. The measurements are performed on microfabricated test chips where resistors are defined in layers grown by molecular beam epitaxy on (0 0 1) silicon substrates. A uniaxial stress along the [1 1 0] direction is applied to the chip, with the use of a four point bending fixture....... The investigation covers materials with doping levels of N-A = 10(18) cm(-3) and NA = 1019 cm(-3), respectively. The results show that the pi(66) piezoresistive coefficient in strained Si0.9Ge0.1 is approximately 30% larger than the comparable pi(44) piezoresistive coefficient in silicon at a doping level of N...

[GM1-dot-EIA for the detection of toxin-producing Vibrio cholerae strains].

Science.gov (United States)

Markina, O V; Alekseeva, L P; Telesmanich, N R; Chemisova, O S; Akulova, M V; Markin, N V

2011-05-01

A new variant of enzyme immunoassay (EIA) has been developed on the basis of GM1 gangliosides to detect the toxin-producing Vibrio cholerae strains--GM1-dot-EIA. Experiments were run using a nitrocellulose membrane to bind GM1 gangliosides and polyclonal antitoxic serum to detect cholerogen. GM1-dot-EIA testing identified cholera toxin in 11 of 13 supernatants of V. cholerae eltor ctx(+) strains isolated from man and in 3 of 7 supernatants of V. cholerae eltor ctx(+) strains isolated from water. These data agree with those obtained in CM1-EIA. There was no reaction with the supernatants of other microorganisms. The sensitivity of the technique was 10 ng/ml. Thus, the simple and specific GM1-dot-EIA may be recommended to detect toxin-producing V cholerae strains isolated from man and water.

IMRT delivery to a moving target by dynamic MLC tracking: delivery for targets moving in two dimensions in the beam's eye view

International Nuclear Information System (INIS)

McQuaid, D; Webb, S

2006-01-01

A new modification of the dynamic multileaf collimator (dMLC) delivery technique for intensity-modulated therapy (IMRT) is outlined. This technique enables the tracking of a target moving through rigid-body translations in a 2D trajectory in the beam's eye view. The accuracy of the delivery versus that of deliveries with no tracking and of 1D tracking techniques is quantified with clinically derived intensity-modulated beams (IMBs). Leaf trajectories calculated in the target-reference frame were iteratively synchronized assuming regular target motion. This allowed the leaves defined in the lab-reference frame to simultaneously follow the target motion and to deliver the required IMB without violation of the leaf maximum-velocity constraint. The leaves are synchronized until the gradient of the leaf position at every instant is less than a calculated maximum. The delivered fluence in the target-reference frame was calculated with a simple primary-fluence model. The new 2D tracking technique was compared with the delivered fluence produced by no-tracking deliveries and by 1D tracking deliveries for 33 clinical IMBs. For the clinical IMBs normalized to a maximum fluence of 200 MUs, the rms difference between the desired and the delivered IMB was 15.6 ± 3.3 MU for the case of a no-tracking delivery, 7.9 ± 1.6 MU for the case where only the primary component of motion was corrected and 5.1 ± 1.1 MU for the 2D tracking delivery. The residual error is due to interpolation and sampling effects. The 2D tracking delivery technique requires an increase in the delivery time evaluated as between 0 and 50% of the unsynchronized delivery time for each beam with a mean increase of 13% for the IMBs tested. The 2D tracking dMLC delivery technique allows an optimized IMB to be delivered to moving targets with increased accuracy and with acceptable increases in delivery time. When combined with real-time knowledge of the target motion at delivery time, this technique facilitates

Métabolisme du méthanol chez les micro-organismes méthylotrophes Metabolism of Methanol in Methylotrophic Microorganisms (Bibliographic Review

Directory of Open Access Journals (Sweden)

Ballerini D.

2006-11-01

Full Text Available De nombreux travaux portant sur l'étude du métabolisme du méthanol chez les bactéries et les levures ont été publiés depuis la fin des années cinquante, et nous permettent d'avoir une meilleure connaissance des mécanismes d'assimilation de ce substrat par les micro-organismes. Cet article précise l'état actuel des connaissances acquises sur les mécanismes d'oxydation du méthanol et sur les deux voies biosynthétiques différentes, la voie sérine et le cycle des ribose-phosphates, trouvées chez les micro-organismes capables d'une croissance méthylotrophique. A great mony research reports on studies of the methanol metabolism in bacteria and yeast has been published since the end of the 1950s and give us a better understanding of the mechanisms by which this substrate is assimulated by microorganisms. This article reviéws the state-of-the-art of knowledge about methanol oxidation mechanisms and two different biosynthesis procedures, 1. e.the serine one and the cycle of the ribose-phosphates found in microorganisms capable of methylotrophic growth.

Genetic homogeneity of Clostridium botulinum type A1 strains with unique toxin gene clusters.

Science.gov (United States)

Raphael, Brian H; Luquez, Carolina; McCroskey, Loretta M; Joseph, Lavin A; Jacobson, Mark J; Johnson, Eric A; Maslanka, Susan E; Andreadis, Joanne D

2008-07-01

A group of five clonally related Clostridium botulinum type A strains isolated from different sources over a period of nearly 40 years harbored several conserved genetic properties. These strains contained a variant bont/A1 with five nucleotide polymorphisms compared to the gene in C. botulinum strain ATCC 3502. The strains also had a common toxin gene cluster composition (ha-/orfX+) similar to that associated with bont/A in type A strains containing an unexpressed bont/B [termed A(B) strains]. However, bont/B was not identified in the strains examined. Comparative genomic hybridization demonstrated identical genomic content among the strains relative to C. botulinum strain ATCC 3502. In addition, microarray data demonstrated the absence of several genes flanking the toxin gene cluster among the ha-/orfX+ A1 strains, suggesting the presence of genomic rearrangements with respect to this region compared to the C. botulinum ATCC 3502 strain. All five strains were shown to have identical flaA variable region nucleotide sequences. The pulsed-field gel electrophoresis patterns of the strains were indistinguishable when digested with SmaI, and a shift in the size of at least one band was observed in a single strain when digested with XhoI. These results demonstrate surprising genomic homogeneity among a cluster of unique C. botulinum type A strains of diverse origin.

Banana (Musa. spp.) strain HD-1 appraisal

International Nuclear Information System (INIS)

Longyan, G.; Xinguo, L.; Lingxia, W.; Xuefei, J.

2016-01-01

Being one of the important tropical and subtropical fruit trees, banana (Musa spp.) belongs to the family Musaceae and the order Scitaminae with two genera, Musa and Ensete. In a field survey, research team has discovered a potential banana mutant strain HD-1 with a sound economic value. The results of the finding are as follows: based on Simmonds classification, the pseudostem of banana strain HD-1 is relatively short and purplish red; its upright outward petiole groove has red edges and wraps its pseudostem loosely. Its ploidy is 3, AAA type. Karyotype analysis shows that the number of chromosomes is 33, the karyotype formula is 2n=3x=33=2L + 3 M2 + 4 M1 + 2 S, HD-1 is classified as 1B type. With the help of ISSR molecular markers, we find thatbanana HD-1 has the closest relationship with Pubei and Tianbao dwarf banana; the similarity coefficient is 0.81. In an artificial simulation tests of cold, drought and salt resistance environment changes of physiological and biochemical indexes indicate that HD-1 exhibits stronger defense capability than Brazil banana. By way of inoculation with injury of root dipping method, we respectively treat two kinds of banana seedlings inoculated Banana Fusarium wilt race 4 small species. The results show that their resistance evaluation scores are 3 and 4, disease levels are susceptible and high sensitivity respectively. We conclude that HD-1 has stronger resistance ability to Fusarium wilt than Brazil banana. (author)

USAFRICOM’s Role in Counter-Piracy Operations Within the Horn of Africa

Science.gov (United States)

2009-05-04

Maritime Bureau (IMB), a division of the International Chamber of Commerce (ICC), established the IMB Piracy Reporting Centre (PRC) in 1992. This...2009). 20 International Chamber of Commerce , International Maritime Bureau, ICC-IMB official website, “International Maritime Bureau”, http...www.icc-ccs.org/, (accessed 15 March 2009). International Chamber of Commerce – International Maritime Bureau, ICC-IMB, Piracy And Armed

Permanent draft genomes of the Rhodopirellula maiorica strain SM1.

Science.gov (United States)

Richter, Michael; Richter-Heitmann, Tim; Klindworth, Anna; Wegner, Carl-Eric; Frank, Carsten S; Harder, Jens; Glöckner, Frank Oliver

2014-02-01

The genome of Rhodopirellula maiorica strain SM1 was sequenced as a permanent draft to complement the full genome sequence of the type strain Rhodopirellula baltica SH1(T). This isolate is part of a larger study to infer the biogeography of Rhodopirellula species in European marine waters, as well as to amend the genus description of R. baltica. This genomics resource article is the fifth of a series of five publications reporting in total eight new permanent daft genomes of Rhodopirellula species. Copyright © 2013 Elsevier B.V. All rights reserved.

A systematic study of the whole genome sequence of Amycolatopsis methanolica strain 239T provides an insight into its physiological and taxonomic properties which correlate with its position in the genus

Directory of Open Access Journals (Sweden)

Biao Tang

2016-09-01

Full Text Available The complete genome of methanol-utilizing Amycolatopsis methanolica strain 239T was generated, revealing a single 7,237,391 nucleotide circular chromosome with 7074 annotated protein-coding sequences (CDSs. Comparative analyses against the complete genome sequences of Amycolatopsis japonica strain MG417-CF17T, Amycolatopsis mediterranei strain U32 and Amycolatopsis orientalis strain HCCB10007 revealed a broad spectrum of genomic structures, including various genome sizes, core/quasi-core/non-core configurations and different kinds of episomes. Although polyketide synthase gene clusters were absent from the A. methanolica genome, 12 gene clusters related to the biosynthesis of other specialized (secondary metabolites were identified. Complete pathways attributable to the facultative methylotrophic physiology of A. methanolica strain 239T, including both the mdo/mscR encoded methanol oxidation and the hps/hpi encoded formaldehyde assimilation via the ribulose monophosphate cycle, were identified together with evidence that the latter might be the result of horizontal gene transfer. Phylogenetic analyses based on 16S rDNA or orthologues of AMETH_3452, a novel actinobacterial class-specific conserved gene against 62 or 18 Amycolatopsis type strains, respectively, revealed three major phyletic lineages, namely the mesophilic or moderately thermophilic A. orientalis subclade (AOS, the mesophilic Amycolatopsis taiwanensis subclade (ATS and the thermophilic A. methanolica subclade (AMS. The distinct growth temperatures of members of the subclades correlated with corresponding genetic variations in their encoded compatible solutes. This study shows the value of integrating conventional taxonomic with whole genome sequence data.

Biodegradation of Nitro-Substituted Explosives 2,4,6-Trinitrotoluene, Hexahydro-1,3,5-Trinitro-1,3,5-Triazine, and Octahydro-1,3,5,7-Tetranitro-1,3,5-Tetrazocine by a Phytosymbiotic Methylobacterium sp. Associated with Poplar Tissues (Populus deltoides × nigra DN34)

Science.gov (United States)

Van Aken, Benoit; Yoon, Jong Moon; Schnoor, Jerald L.

2004-01-01

A pink-pigmented symbiotic bacterium was isolated from hybrid poplar tissues (Populus deltoides × nigra DN34). The bacterium was identified by 16S and 16S-23S intergenic spacer ribosomal DNA analysis as a Methylobacterium sp. (strain BJ001). The isolated bacterium was able to use methanol as the sole source of carbon and energy, which is a specific attribute of the genus Methylobacterium. The bacterium in pure culture was shown to degrade the toxic explosives 2,4,6-trinitrotoluene (TNT), hexahydro-1,3,5-trinitro-1,3,5-triazene (RDX), and octahydro-1,3,5,7-tetranitro-1,3,5-tetrazocine (HMX). [U-ring-14C]TNT (25 mg liter−1) was fully transformed in less than 10 days. Metabolites included the reduction derivatives amino-dinitrotoluenes and diamino-nitrotoluenes. No significant release of 14CO2 was recorded from [14C]TNT. In addition, the isolated methylotroph was shown to transform [U-14C]RDX (20 mg liter−1) and [U-14C]HMX (2.5 mg liter−1) in less than 40 days. After 55 days of incubation, 58.0% of initial [14C]RDX and 61.4% of initial [14C]HMX were mineralized into 14CO2. The radioactivity remaining in solution accounted for 12.8 and 12.7% of initial [14C]RDX and [14C]HMX, respectively. Metabolites detected from RDX transformation included a mononitroso RDX derivative and a polar compound tentatively identified as methylenedinitramine. Since members of the genus Methylobacterium are distributed in a wide diversity of natural environments and are very often associated with plants, Methylobacterium sp. strain BJ001 may be involved in natural attenuation or in situ biodegradation (including phytoremediation) of explosive-contaminated sites. PMID:14711682

Characterization of European Yersinia enterocolitica 1A strains using restriction fragment length polymorphism and multilocus sequence analysis.

Science.gov (United States)

Murros, A; Säde, E; Johansson, P; Korkeala, H; Fredriksson-Ahomaa, M; Björkroth, J

2016-10-01

Yersinia enterocolitica is currently divided into two subspecies: subsp. enterocolitica including highly pathogenic strains of biotype 1B and subsp. palearctica including nonpathogenic strains of biotype 1A and moderately pathogenic strains of biotypes 2-5. In this work, we characterized 162 Y. enterocolitica strains of biotype 1A and 50 strains of biotypes 2-4 isolated from human, animal and food samples by restriction fragment length polymorphism using the HindIII restriction enzyme. Phylogenetic relatedness of 20 representative Y. enterocolitica strains including 15 biotype 1A strains was further studied by the multilocus sequence analysis of four housekeeping genes (glnA, gyrB, recA and HSP60). In all the analyses, biotype 1A strains formed a separate genomic group, which differed from Y. enterocolitica subsp. enterocolitica and from the strains of biotypes 2-4 of Y. enterocolitica subsp. palearctica. Based on these results, biotype 1A strains considered nonpathogenic should not be included in subspecies palearctica containing pathogenic strains of biotypes 2-5. Yersinia enterocolitica strains are currently divided into six biotypes and two subspecies. Strains of biotype 1A, which are phenotypically and genotypically very heterogeneous, are classified as subspecies palearctica. In this study, European Y. enterocolitica 1A strains isolated from both human and nonhuman sources were characterized using restriction fragment length polymorphism and multilocus sequence analysis. The European biotype 1A strains formed a separate group, which differed from strains belonging to subspecies enterocolitica and palearctica. This may indicate that the current division between the two subspecies is not sufficient considering the strain diversity within Y. enterocolitica. © 2016 The Society for Applied Microbiology.

The abundance of pink-pigmented facultative methylotrophs in the root zone of plant species in invaded coastal sage scrub habitat.

Science.gov (United States)

Irvine, Irina C; Brigham, Christy A; Suding, Katharine N; Martiny, Jennifer B H

2012-01-01

Pink-pigmented facultative methylotrophic bacteria (PPFMs) are associated with the roots, leaves and seeds of most terrestrial plants and utilize volatile C(1) compounds such as methanol generated by growing plants during cell division. PPFMs have been well studied in agricultural systems due to their importance in crop seed germination, yield, pathogen resistance and drought stress tolerance. In contrast, little is known about the PPFM abundance and diversity in natural ecosystems, let alone their interactions with non-crop species. Here we surveyed PPFM abundance in the root zone soil of 5 native and 5 invasive plant species along ten invasion gradients in Southern California coastal sage scrub habitat. PPFMs were present in every soil sample and ranged in abundance from 10(2) to 10(5) CFU/g dry soil. This abundance varied significantly among plant species. PPFM abundance was 50% higher in the root zones of annual or biennial species (many invasives) than perennial species (all natives). Further, PPFM abundance appears to be influenced by the plant community beyond the root zone; pure stands of either native or invasive species had 50% more PPFMs than mixed species stands. In sum, PPFM abundance in the root zone of coastal sage scrub plants is influenced by both the immediate and surrounding plant communities. The results also suggest that PPFMs are a good target for future work on plant-microorganism feedbacks in natural ecosystems.

Cafestol Inhibits Cyclic-Strain-Induced Interleukin-8, Intercellular Adhesion Molecule-1, and Monocyte Chemoattractant Protein-1 Production in Vascular Endothelial Cells

Science.gov (United States)

Hao, Wen-Rui; Sung, Li-Chin; Chen, Chun-Chao; Chen, Jin-Jer

2018-01-01

Moderate coffee consumption is inversely associated with cardiovascular disease mortality; however, mechanisms underlying this causal effect remain unclear. Cafestol, a diterpene found in coffee, has various properties, including an anti-inflammatory property. This study investigated the effect of cafestol on cyclic-strain-induced inflammatory molecule secretion in vascular endothelial cells. Cells were cultured under static or cyclic strain conditions, and the secretion of inflammatory molecules was determined using enzyme-linked immunosorbent assay. The effects of cafestol on mitogen-activated protein kinases (MAPK), heme oxygenase-1 (HO-1), and sirtuin 1 (Sirt1) signaling pathways were examined using Western blotting and specific inhibitors. Cafestol attenuated cyclic-strain-stimulated intercellular adhesion molecule-1 (ICAM-1), monocyte chemoattractant protein- (MCP-) 1, and interleukin- (IL-) 8 secretion. Cafestol inhibited the cyclic-strain-induced phosphorylation of extracellular signal-regulated kinase and p38 MAPK. By contrast, cafestol upregulated cyclic-strain-induced HO-1 and Sirt1 expression. The addition of zinc protoporphyrin IX, sirtinol, or Sirt1 silencing (transfected with Sirt1 siRNA) significantly attenuated cafestol-mediated modulatory effects on cyclic-strain-stimulated ICAM-1, MCP-1, and IL-8 secretion. This is the first study to report that cafestol inhibited cyclic-strain-induced inflammatory molecule secretion, possibly through the activation of HO-1 and Sirt1 in endothelial cells. The results provide valuable insights into molecular pathways that may contribute to the effects of cafestol. PMID:29854096

Coherently Strained Si-SixGe1-x Core-Shell Nanowire Heterostructures.

Science.gov (United States)

Dillen, David C; Wen, Feng; Kim, Kyounghwan; Tutuc, Emanuel

2016-01-13

Coherently strained Si-SixGe1-x core-shell nanowire heterostructures are expected to possess a positive shell-to-core conduction band offset, allowing for quantum confinement of electrons in the Si core. We report the growth of epitaxial, coherently strained Si-SixGe1-x core-shell heterostructures through the vapor-liquid-solid mechanism for the Si core, followed in situ by the epitaxial SixGe1-x shell growth using ultrahigh vacuum chemical vapor deposition. The Raman spectra of individual nanowires reveal peaks associated with the Si-Si optical phonon mode in the Si core and the Si-Si, Si-Ge, and Ge-Ge vibrational modes of the SixGe1-x shell. The core Si-Si mode displays a clear red-shift compared to unstrained, bare Si nanowires thanks to the lattice mismatch-induced tensile strain, in agreement with calculated values using a finite-element continuum elasticity model combined with lattice dynamic theory. N-type field-effect transistors using Si-SixGe1-x core-shell nanowires as channel are demonstrated.

Immunization by intrabronchial administration to 1-week-old foals of an unmarked double gene disruption strain of Rhodococcus equi strain 103+.

Science.gov (United States)

Pei, Yanlong; Nicholson, Vivian; Woods, Katharine; Prescott, John F

2007-11-15

Rhodococcus equi causes fatal granulomatous pneumonia in foals and immunocompromised animals and humans. However, there is no effective vaccine against this infection. In this study, the chromosomal genes isocitrate lyase (icl) and cholesterol oxidase (choE) were chosen as targets for mutation and assessment of the double mutant as an intrabronchial vaccine in 1-week-old foals. Using a modification of a suicide plasmid previously developed in this laboratory, we developed a choE-icl unmarked deletion mutant of R. equi strain 103+. Five 1-week-old foals were infected intrabronchially with the mutant and challenged intrabronchially with the parent, virulent, strain 2 weeks later. Three of the foals were protected against pneumonia caused by the virulent strain, but the other two foals developed pneumonia caused by the mutant strain during the post-challenge period. Since infection of 3-week-old foals by an icl mutant in an earlier study had shown complete attenuation of the strain, we conclude that a proportion of foals in the 1st week or so of life are predisposed to developing R. equi pneumonia because of an inability to mount an effective immune response. This has been suspected previously but this is the first time that this has been demonstrated experimentally.

Proteomic Profiling of Mesenchymal Stem Cell Responses to Mechanical Strain and TGF-B1

Energy Technology Data Exchange (ETDEWEB)

Kurpinski, Kyle; Chu, Julia; Wang, Daojing; Li, Song

2009-10-12

Mesenchymal stem cells (MSCs) are a potential source of smooth muscle cells (SMCs) for constructing tissue-engineered vascular grafts. However, the details of how specific combinations of vascular microenvironmental factors regulate MSCs are not well understood. Previous studies have suggested that both mechanical stimulation with uniaxial cyclic strain and chemical stimulation with transforming growth factor {beta}1 (TGF-{beta}1) can induce smooth muscle markers in MSCs. In this study, we investigated the combined effects of uniaxial cyclic strain and TGF-{beta}1 stimulation on MSCs. By using a proteomic analysis, we found differential regulation of several proteins and genes, such as the up-regulation of TGF-{beta}1-induced protein ig-h3 (BGH3) protein levels by TGF-{beta}1 and up-regulation of calponin 3 protein level by cyclic strain. At the gene expression level, BGH3 was induced by TGF-{beta}1, but calponin 3 was not significantly regulated by mechanical strain or TGF-{beta}1, which was in contrast to the synergistic up-regulation of calponin 1 gene expression by cyclic strain and TGF-{beta}1. Further experiments with cycloheximide treatment suggested that the up-regulation of calponin 3 by cyclic strain was at post-transcriptional level. The results in this study suggest that both mechanical stimulation and TGF-{beta}1 signaling play unique and important roles in the regulation of MSCs at both transcriptional and post-transcriptional levels, and that a precise combination of microenvironmental cues may promote MSC differentiation.

Genetic characterization of enterovirus strains identified in Hand, Foot and Mouth Disease (HFMD): Emergence of B1c, C1 subgenotypes, E2 sublineage of CVA16, EV71 and CVA6 strains in India.

Science.gov (United States)

Ganorkar, Nital N; Patil, Pooja R; Tikute, Sanjay S; Gopalkrishna, Varanasi

2017-10-01

Hand, Foot and Mouth disease (HFMD) is a common childhood disease and caused due to Enterovirus-A (EV-A), EV-B and EV-C species worldwide. Cases of HFMD were reported from, Ahmedabad (Gujarat, 2012) and Pune (Maharashtra, 2013-2014) in India. The present study highlights the identification of EV strains (CVA16, CVA6, CVA4 and Echo12), characterization of subgenotypes of CVA16, CVA6 strains during 2012-14 and CVA16, CVA6, EV71 strains reported from the earlier study (2009-10) in HFMD cases from India. A total 158 clinical specimens collected from 64 HFMD cases (2012-2014) were included in the study. EV detection was carried out by 5'NCR based RT-PCR, molecular typing and subgenotyping was by VP1/2A junction or VP1, full VP1 gene amplification respectively followed by phylogenetic analysis. The present study reports 63.92% (101/158) EV positivity by RT-PCR. Ninety four of the 101 (93.06%) EV positive strains were amplified by VP1/2A junction or VP1 regions. Sequence analysis revealed the presence of CVA16 (61.7%), CVA6 (34.04%), CVA4 and Echo12 (4.3%). A total of 114 EV positive strains were genotyped using full and partial VP1 region. All CVA16 Indian strains (n=70) clustered with rarely reported B1c subgenotype, CVA6 (n=43) and EV71 (n=1) strains clustered with sub-lineage E2 and C1 subgenotypes respectively. In summary, the study reports genetic characterization of CVA16, CVA6, CVA4 and Echo12 strains in HFMD cases from India. Circulation of B1c subgenotype of CVA16, E2 sub-lineage of CVA6 and C1 subgenotype of EV 71 strains in HFMD cases were reported for the first time from India. This study helps to understand the genotype distribution, genetic diversity of EV strains associated with HFMD from Eastern, Western and Southern regions in India. Copyright © 2017 Elsevier B.V. All rights reserved.

Remarkable strain-induced magnetic anisotropy in epitaxial Co2MnGa (0 0 1) films

International Nuclear Information System (INIS)

Pechan, Michael J.; Yu, Chengtao; Carr, David; Palmstroem, Chris J.

2005-01-01

Remarkably large, strain-induced anisotropy is observed in the thin-film Heusler alloy Co 2 MnGa. 30 nm Co 2 MnGa (0 0 1) films have been epitaxially grown on different interlayers/substrates with varied strain, and investigated with ferromagnetic resonance. The film grown on ErAs/InGaAs/InP experiences tension strain, resulting in an out-of-plane strain-induced anisotropy (∼1.1x10 6 erg/cm 3 ) adding to the effects of shape anisotropy. In contrast, the film grown on ScErAs/GaAs, experiences a compression strain, resulting in an out-of-plane strain-induced anisotropy (∼3.3x10 6 erg/cm 3 ) which almost totally cancels the effects of shape anisotropy, thus rendering the film virtually isotropic. This results in the formation of stripe domains in remanence. In addition, small, but well-defined 2-fold and 4-fold in-plane anisotropy coexist in each sample with weak, but interesting strain dependence. Transport measurement shows small (<1%) magnetoresistance effects in the compression film, but negligible magnetoresistance in the relaxed and tension strained samples

Short-period strain (0.1-105 s): Near-source strain field for an earthquake (M L 3.2) near San Juan Bautista, California

Science.gov (United States)

Johnston, M. J. S.; Borcherdt, R. D.; Linde, A. T.

1986-10-01

Measurements of dilational earth strain in the frequency band 25-10-5 Hz have been made on a deep borehole strainmeter installed near the San Andreas fault. These data are used to determine seismic radiation fields during nuclear explosions, teleseisms, local earthquakes, and ground noise during seismically quiet times. Strains of less than 10-10 on these instruments can be clearly resolved at short periods (< 10 s) and are recorded with wide dynamic range digital recorders. This permits measurement of the static and dynamic strain variations in the near field of local earthquakes. Noise spectra for earth strain referenced to 1 (strain)2/Hz show that strain resolution decreases at about 10 dB per decade of frequency from -150 dB at 10-4 Hz to -223 dB at 10 Hz. Exact expressions are derived to relate the volumetric strain and displacement field for a homogeneous P wave in a general viscoelastic solid as observed on colocated dilatometers and seismometers. A rare near-field recording of strain and seismic velocity was obtained on May 26, 1984, from an earthquake (ML 3.2) at a hypocentral distance of 3.2 km near the San Andreas fault at San Juan Bautista, California. While the data indicate no precursory strain release at the 5 × 10-11 strain level, a coseismic strain release of 1.86 nanostrain was observed. This change in strain is consistent with that calculated from a simple dislocation model of the event. Ground displacement spectra, determined from the downhole strain data and instrument-corrected surface seismic data, suggest that source parameters estimated from surface recordings may be contaminated by amplification effects in near-surface low-velocity materials.

Flavins mediate extracellular electron transfer in Gram-positive Bacillus megaterium strain LLD-1

DEFF Research Database (Denmark)

You, Le-Xing; Liu, Li-Dan; Xiao, Yong

2018-01-01

The extracellular electron transfer (EET) mechanism of an isolated Gram-positive Bacillus megaterium strain (LLD-1), identified by 16S rRNA gene sequencing and physiological analysis, was investigated in the present study. The electrochemical activity of strain LLD-1 was confirmed by electrochemi...

Determining Smoking Cessation Related Information, Motivation, and Behavioral Skills among Opiate Dependent Smokers in Methadone Treatment.

Science.gov (United States)

Cooperman, Nina A; Richter, Kimber P; Bernstein, Steven L; Steinberg, Marc L; Williams, Jill M

2015-04-01

Over 80% of people in methadone treatment smoke cigarettes, and existing smoking cessation interventions have been minimally effective. To develop an Information-Motivation-Behavioral Skills (IMB) Model of behavior change based smoking cessation intervention for methadone maintained smokers, we examined smoking cessation related IMB factors in this population. Current or former smokers in methadone treatment (n = 35) participated in focus groups. Ten methadone clinic counselors participated in an individual interview. A content analysis was conducted using deductive and inductive approaches. Commonly known IMB factors related to smoking cessation were described. These factors included: the health effects of smoking and treatment options for quitting (information); pregnancy and cost of cigarettes (motivators); and coping with emotions, finding social support, and pharmacotherapy adherence (behavioral skills). IMB factors specific to methadone maintained smokers were also described. These factors included: the relationship between quitting smoking and drug relapse (information), the belief that smoking is the same as using drugs (motivator); and coping with methadone clinic culture and applying skills used to quit drugs to quitting smoking (behavioral skills). IMB strengths and deficits varied by individual. Methadone maintained smokers could benefit from research on an IMB Model based smoking cessation intervention that is individualized, addresses IMB factors common among all smokers, and also addresses IMB factors unique to this population.

Microbial growth on C1 compounds: proceedings

International Nuclear Information System (INIS)

Crawford, R.L.; Hanson, R.S.

1984-01-01

This book contains individual papers prepared for the 4th International Symposium on Microbial Growth on One Carbon Compounds. Individual reports were abstracted and indexed for EDB. Topics presented were in the areas of the physiology and biochemistry of autotraps, physiology and biochemistry of methylotrophs and methanotrops, physiology and biochemistry of methanogens, genetics of microbes that use C 1 compounds, taxonomy and ecology of microbes tht grow on C 1 compounds, applied aspects of microbes that grow on C 1 compounds, and new directions in C 1 metabolism. (DT)

Metabolic regulation in the facultative methylotroph arthrobacter P1

NARCIS (Netherlands)

1985-01-01

Many microorganisms are able to utilize C1 compounds, i.e. compounds which do not contain carbon-carbon bonds, as carbon- and energy sources for growth. In order to synthesize cell constituents from these C1 compounds special metabolic pathways are employed by such organisms. Although a great deal

Effect of strain on evolution of dynamic recrystallization in Nb-1 wt%Zr-0.1 wt%C alloy at 1500 and 1600 °C

Energy Technology Data Exchange (ETDEWEB)

Behera, A.N. [Mechanical Metallurgy Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Homi Bhabha National Institute, Anushakti Nagar, Mumbai 400094 (India); Kapoor, R., E-mail: rkapoor@barc.gov.in [Mechanical Metallurgy Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Homi Bhabha National Institute, Anushakti Nagar, Mumbai 400094 (India); Paul, B. [Materials Processing & Corrosion Engineering Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Chakravartty, J.K. [Mechanical Metallurgy Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)

2017-04-15

Uniaxial compression tests were carried out on Nb-1 wt%Zr-0.1 wt%C alloy at temperature of 1500 and 1600 °C and strain rate of 0.1 s{sup −1} to study the evolution of dynamic recrystallization with strain. Electron back scatter diffraction was used to quantify the microstructural evolution. Nb-1Zr-0.1C alloy showed a necklace structure at a strain of 0.9 when deformed at 1500 °C and at strain of 0.6 when deformed at 1600 °C, both at strain rate of 0.1 s{sup −1}. This suggested the occurrence of dynamic recrystallization. At 1500 °C and strain of 0.9 the local average misorientation and the grain orientation spread was low confirming the presence of dynamic recrystallization at this deformation condition. At both 1500 and 1600 °C and all measured strains the recrystallized grains had a strong fiber component of <001>. - Highlights: • Necklace formation of dynamically recrystallized grains occurred at strain of 0.6 and 0.9 for 1500 and 1600 °C, respectively. • Equiaxed microstructures were seen with increase in strain for both 1500 and 1600 °C. • At large strains the predominant recrystallized texture evolved to <001> pole.

Detection of cholera (ctx) and zonula occludens (zot) toxin genes in Vibrio cholerae O1, O139 and non-O1 strains.

Science.gov (United States)

Rivera, I G; Chowdhury, M A; Sanchez, P S; Sato, M I; Huq, A; Colwell, R R; Martins, M T

1995-09-01

Vibrio cholerae O1 and V. cholerae non-O1 strains isolated from environmental samples collected in São Paulo, Brazil, during cholera epidemics and pre-epidemic periods were examined for the presence of toxin genes. V. cholerae O1 strains isolated from clinical samples in Peru and Mexico, and V. cholerae O139 strains from India were also examined for the presence of ctx (cholera toxin gene) and zot (zonula occludens toxin gene) by polymerase chain reaction (PCR). A modified DNA-extraction method applied in this study yielded satisfactory recovery of genomic DNA from vibrios. Results showed that strains of V. cholerae O1 isolated during the preepidemic period were ctx (-)/zot (-) whereas strains isolated during the epidemic were ctx (+)/zot (+). All V. cholerae non-O1 strains tested in the study were ctx (-)/zot (-), whereas all V. cholerae O139 strains were ctx (+)/zot (+). Rapid detection of the virulence genes (ctx and zot) can be achieved by PCR and this can serve as an important tool in the epidemiology and surveillance of V. cholerae.

Physiological studies in aerobic batch cultivations of Saccharomyces cerevisiae strains harboring the MEL1 gene

DEFF Research Database (Denmark)

Østergaard, Simon; Roca, Christophe Francois Aime; Ronnow, B.

2000-01-01

Physiological studies of Saccharomyces cerevisiae strains harboring the MEL1 gene were carried out in aerobic batch cultivations on glucose-galactose mixtures and on the disaccharide melibiose, which is hydrolyzed by the enzyme melibiase (Mel1, EC 3.2.1.22) into a glucose and a galactose moiety...... rates were 2.5-3.3-fold higher on glucose than on galactose for all the strains examined, and hence, ethanol production was pronounced on glucose due to respiro-fermentative metabolism. The T256 strain and the T200 strain having the MEL1 gene inserted in the HXK2 locus and the LEU2 locus, respectively...

Hansschlegelia beijingensis sp. nov., an aerobic, pink-pigmented, facultatively methylotrophic bacterium isolated from watermelon rhizosphere soil.

Science.gov (United States)

Zou, Xiao-lin; Li, Xiu-ai; Wang, Xu-Ming; Chen, Qiang; Gao, Miao; Qiu, Tian-lei; Sun, Jian-guang; Gao, Jun-lian

2013-10-01

A novel Gram-stain-negative, aerobic, rod-shaped strain designated PG04(T) was isolated from the rhizosphere of watermelon plants cultivated in Beijing, China. A polyphasic taxonomic study was performed on the new isolate. On the basis of 16S rRNA gene sequence similarity studies, isolate PG04(T) belonged clearly to the genus Hansschlegelia and was most closely related to Hansschlegelia zhihuaiae (97.3 % similarity to the type strain). The predominant respiratory quinone was ubiquinone 10 (Q-10) and the polar lipid profile was composed of the major lipids diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and phosphatidylcholine. The major fatty acids were C18 : 1ω7c (41.3 %), C19 : 0 cyclo ω8c (30.6 %) and C16 : 0 (19.1 %). The G+C content of the DNA was about 64.4 mol%. DNA-DNA hybridization experiments showed 34.4 % relatedness between strain PG04(T) and H. zhihuaiae DSM 18984(T). The results of physiological and biochemical tests and differences in fatty acid profiles allowed clear phenotypic differentiation of strain PG04(T) from the most closely related species in the genus, H. zhihuaiae. Strain PG04(T) therefore represents a novel species within the genus Hansschlegelia, for which the name Hansschlegelia beijingensis sp. nov. is proposed, with the type strain PG04(T) ( = DSM 25481(T) = ACCC 05759(T)).

Genetic variation of viral protein 1 genes of field strains of waterfowl parvoviruses and their attenuated derivatives.

Science.gov (United States)

Tsai, Hsiang-Jung; Tseng, Chun-hsien; Chang, Poa-chun; Mei, Kai; Wang, Shih-Chi

2004-09-01

To understand the genetic variations between the field strains of waterfowl parvoviruses and their attenuated derivatives, we analyzed the complete nucleotide sequences of the viral protein 1 (VP1) genes of nine field strains and two vaccine strains of waterfowl parvoviruses. Sequence comparison of the VP1 proteins showed that these viruses could be divided into goose parvovirus (GPV) related and Muscovy duck parvovirus (MDPV) related groups. The amino acid difference between GPV- and MDPV-related groups ranged from 13.1% to 15.8%, and the most variable region resided in the N terminus of VP2. The vaccine strains of GPV and MDPV exhibited only 1.2% and 0.3% difference in amino acid when compared with their parental field strains, and most of these differences resided in residues 497-575 of VP1, suggesting that these residues might be important for the attenuation of GPV and MDPV. When the GPV strains isolated in 1982 (the strain 82-0308) and in 2001 (the strain 01-1001) were compared, only 0.3% difference in amino acid was found, while MDPV strains isolated in 1990 (the strain 90-0219) and 1997 (the strain 97-0104) showed only 0.4% difference in amino acid. The result indicates that the genome of waterfowl parvovirus had remained highly stable in the field.

Genome Sequence of Gluconacetobacter sp. Strain SXCC-1, Isolated from Chinese Vinegar Fermentation Starter▿

OpenAIRE

Du, Xin-jun; Jia, Shi-ru; Yang, Yue; Wang, Shuo

2011-01-01

Gluconacetobacter strains are prominent bacteria during traditional vinegar fermentation. Here, we report a draft genome sequence of Gluconacetobacter sp. strain SXCC-1. This strain was isolated from a fermentation starter (Daqu) used for commercial production of Shanxi vinegar, the best-known vinegar of China.

Isolation of Mycobacterium paratuberculosis from Milk by Immunomagnetic Separation

OpenAIRE

Grant, Irene R.; Ball, Hywel J.; Rowe, Michael T.

1998-01-01

An immunomagnetic separation (IMS) technique was developed to facilitate selective isolation of Mycobacterium paratuberculosis cells from milk. Rabbit polyclonal antibodies against radiation-killed intact M. paratuberculosis cells were produced and used to coat sheep anti-rabbit immunoglobulin G (IgG) type M-280 Dynabeads. The rabbit anti-M. paratuberculosis IgG-coated beads (IMB) reacted strongly with laboratory strains of M. paratuberculosis as determined by slide agglutination, and microsc...

Genetic characterization of circulating seasonal Influenza A viruses (2005-2009) revealed introduction of oseltamivir resistant H1N1 strains during 2009 in eastern India.

Science.gov (United States)

Agrawal, Anurodh S; Sarkar, Mehuli; Ghosh, Swati; Roy, Tapasi; Chakrabarti, Sekhar; Lal, Renu; Mishra, Akhilesh C; Chadha, Mandeep S; Chawla-Sarkar, Mamta

2010-12-01

Influenza surveillance was implemented in Kolkata, eastern India in 2005 to identify the circulating subtypes and characterize their genetic diversity. Throat and nasal swabs were collected from outpatients with influenza-like illness (ILI). Of 2844 ILI cases identified at two referral hospitals during October 2005-September 2009, 309 (10.86%) were positive for Influenza A by real time RT-PCR, of which 110 (35.60%) were subtyped as H1N1 and 199 (64.40%) as H3N2. Comparison of the nucleotide (nt) and amino acid (aa) sequences of the HA1 gene for H1N1 and H3N2 strains showed that a subset of strains precede WHO recommended contemporary strains by 1-2 years. The Kolkata H1N1 strains clustered in Clade II, subgroup 2B with A/Brisbane/59/2007 but were distant from the corresponding vaccine strains (New Caledonia/20/99 and A/Solomon Island/3/06). The 2005-06 and 2007 H3N2 strains (15/17) clustered either A/Brisbane/10/2007-like (n=8) or A/Nepal/921/2006 like (n=7) strains, whereas 2008 strains (8/12) and 2009 strains (4/4) were similar to the 2010-11 vaccine strain A/Perth/16/2009. More aa substitutions were found in HA or NA genes of H3N2 than in H1N1 strains. No mutation conferring neuraminidase resistance was observed in any of the strain during 2005-08, however in 2009, drug resistant marker (H275Y) was present in seasonal H1N1, but not in co-circulating H3N2 strains. This is the first report of genetic characterization of circulating Influenza A strains from India. The results also highlight the importance of continuing Influenza surveillance in developing countries of Asia for monitoring unusual strains with pandemic potential and mutations conferring antiviral resistance. Copyright © 2010 Elsevier B.V. All rights reserved.

Engineering of nearly strain-free ZnO films on Si(1 1 1) by tuning AlN buffer thickness

International Nuclear Information System (INIS)

Venkatachalapathy, Vishnukanthan; Galeckas, Augustinas; Lee, In-Hwan; Kuznetsov, Andrej Yu.

2012-01-01

ZnO properties were investigated as a function of AlN buffer layer thickness (0–100 nm) in ZnO/AlN/Si(1 1 1) structures grown by metal organic vapor phase epitaxy. A significant improvement of ZnO film crystallinity by tuning AlN buffer thickness was confirmed by x-ray diffraction, topography and photoluminescence measurements. An optimal AlN buffer layer thickness of 50 nm is defined, which allows for growth of nearly strain-free ZnO films. The presence of free excitons at 10 K suggests high crystal quality for all ZnO samples grown on AlN/Si(1 1 1) templates. The intensities of neutral and ionized donor bound exciton lines are found to correlate with the in-plane and out-of-plane strain in the films, respectively.

Engineering of nearly strain-free ZnO films on Si(1 1 1) by tuning AlN buffer thickness

Energy Technology Data Exchange (ETDEWEB)

Venkatachalapathy, Vishnukanthan, E-mail: vishnukanthan.venkatachalapathy@smn.uio.no [Department of Physics/Centre for Materials Science and Nanotechnology, University of Oslo, P.O. Box 1048 Blindern, NO-0316 Oslo (Norway); Galeckas, Augustinas [Department of Physics/Centre for Materials Science and Nanotechnology, University of Oslo, P.O. Box 1048 Blindern, NO-0316 Oslo (Norway); Lee, In-Hwan [School of Advanced Materials Engineering, Research Centre for Advanced Materials Development (RCAMD), Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Kuznetsov, Andrej Yu. [Department of Physics/Centre for Materials Science and Nanotechnology, University of Oslo, P.O. Box 1048 Blindern, NO-0316 Oslo (Norway)

2012-05-15

ZnO properties were investigated as a function of AlN buffer layer thickness (0-100 nm) in ZnO/AlN/Si(1 1 1) structures grown by metal organic vapor phase epitaxy. A significant improvement of ZnO film crystallinity by tuning AlN buffer thickness was confirmed by x-ray diffraction, topography and photoluminescence measurements. An optimal AlN buffer layer thickness of 50 nm is defined, which allows for growth of nearly strain-free ZnO films. The presence of free excitons at 10 K suggests high crystal quality for all ZnO samples grown on AlN/Si(1 1 1) templates. The intensities of neutral and ionized donor bound exciton lines are found to correlate with the in-plane and out-of-plane strain in the films, respectively.

The abundance of pink-pigmented facultative methylotrophs in the root zone of plant species in invaded coastal sage scrub habitat.

Directory of Open Access Journals (Sweden)

Irina C Irvine

Full Text Available Pink-pigmented facultative methylotrophic bacteria (PPFMs are associated with the roots, leaves and seeds of most terrestrial plants and utilize volatile C(1 compounds such as methanol generated by growing plants during cell division. PPFMs have been well studied in agricultural systems due to their importance in crop seed germination, yield, pathogen resistance and drought stress tolerance. In contrast, little is known about the PPFM abundance and diversity in natural ecosystems, let alone their interactions with non-crop species. Here we surveyed PPFM abundance in the root zone soil of 5 native and 5 invasive plant species along ten invasion gradients in Southern California coastal sage scrub habitat. PPFMs were present in every soil sample and ranged in abundance from 10(2 to 10(5 CFU/g dry soil. This abundance varied significantly among plant species. PPFM abundance was 50% higher in the root zones of annual or biennial species (many invasives than perennial species (all natives. Further, PPFM abundance appears to be influenced by the plant community beyond the root zone; pure stands of either native or invasive species had 50% more PPFMs than mixed species stands. In sum, PPFM abundance in the root zone of coastal sage scrub plants is influenced by both the immediate and surrounding plant communities. The results also suggest that PPFMs are a good target for future work on plant-microorganism feedbacks in natural ecosystems.

High strain rate tensile behavior of Al-4.8Cu-1.2Mg alloy

International Nuclear Information System (INIS)

Bobbili, Ravindranadh; Paman, Ashish; Madhu, V.

2016-01-01

The purpose of the current study is to perform quasi static and high strain rate tensile tests on Al-4.8Cu-1.2Mg alloy under different strain rates ranging from 0.01–3500/s and also at temperatures of 25,100, 200 and 300 °C. The combined effect of strain rate, temperature and stress triaxiality on the material behavior is studied by testing both smooth and notched specimens. Johnson–Cook (J–C) constitutive and fracture models are established based on high strain rate tensile data obtained from Split hopkinson tension bar (SHTB) and quasi-static tests. By modifying the strain hardening and strain rate hardening terms in the Johnson–Cook (J–C) constitutive model, a new J–C constitutive model of Al-4.8Cu-1.2Mg alloy was obtained. The improved Johnson–Cook constitutive model matched the experiment results very well. With the Johnson–Cook constitutive and fracture models, numerical simulations of tensile tests at different conditions for Al-4.8Cu-1.2Mg alloy were conducted. Numerical simulations are performed using a non-linear explicit finite element code autodyn. Good agreement is obtained between the numerical simulation results and the experiment results. The fracture surfaces of specimens tested under various strain rates and temperatures were studied under scanning electron microscopy (SEM).

A new human male diploid cell strain, TIG-7: its age-related changes and comparison with a matched female TIG-1 cell strain.

Science.gov (United States)

Yamamoto, K; Kaji, K; Kondo, H; Matsuo, M; Shibata, Y; Tasaki, Y; Utakoji, T; Ooka, H

1991-01-01

A new human diploid cell strain, TIG-7, which has the male karyotype, was established and characterized. Isozyme and histocompatibility typing of the cell strain was performed. The average in vitro life span of the cells is 73 population doublings. Changes in cell volume, doubling time, saturation density, the efficiency of cell attachment, plating efficiency, and relative DNA content were examined during in vitro cellular aging. Hydrocortisone slightly prolongs the life span of the cell strain when the hormone is administered to the cultures during middle passages. The age-related changes in the parameters of TIG-7 are not appreciably different from those of the previously established TIG-1 cell strain. These results show that this cell strain is useful for research on cellular aging; further profit is anticipated from research using a combination of these two sexually different cell strains.

Survival and death of the haloarchaeon Natronorubrum strain HG-1 in a simulated martian environment

Science.gov (United States)

Peeters, Z.; Vos, D.; ten Kate, I. L.; Selch, F.; van Sluis, C. A.; Sorokin, D. Yu.; Muijzer, G.; Stan-Lotter, H.; van Loosdrecht, M. C. M.; Ehrenfreund, P.

2010-11-01

Halophilic archaea are of interest to astrobiology due to their survival capabilities in desiccated and high salt environments. The detection of remnants of salty pools on Mars stimulated investigations into the response of haloarchaea to martian conditions. Natronorubrum sp. strain HG-1 is an extremely halophilic archaeon with unusual metabolic pathways, growing on acetate and stimulated by tetrathionate. We exposed Natronorubrum strain HG-1 to ultraviolet (UV) radiation, similar to levels currently prevalent on Mars. In addition, the effects of low temperature (4, -20, and -80 °C), desiccation, and exposure to a Mars soil analogue from the Atacama desert on the viability of Natronorubrum strain HG-1 cultures were investigated. The results show that Natronorubrum strain HG-1 cannot survive for more than several hours when exposed to UV radiation equivalent to that at the martian equator. Even when protected from UV radiation, viability is impaired by a combination of desiccation and low temperature. Desiccating Natronorubrum strain HG-1 cells when mixed with a Mars soil analogue impaired growth of the culture to below the detection limit. Overall, we conclude that Natronorubrum strain HG-1 cannot survive the environment currently present on Mars. Since other halophilic microorganisms were reported to survive simulated martian conditions, our results imply that survival capabilities are not necessarily shared between phylogenetically related species.

Structural and functional characterization of recombinant napin-like protein of Momordica charantia expressed in methylotrophic yeast Pichia pastoris.

Science.gov (United States)

Yadav, Shailesh Kumar R; Sahu, Tejram; Dixit, Aparna

2016-08-01

Napin and napin-like proteins belong to the 2S albumin seed storage family of proteins and have been shown to display a variety of biological activities. However, due to a high degree of polymorphism, purification of a single napin or napin-like protein exhibiting biological activity is extremely difficult. In the present study, we have produced the napin-like protein of Momordica charantia using the methylotrophic Pichia pastoris expression system. The recombinant napin-like protein (rMcnapin) secreted in the extracellular culture supernatant was enriched by ammonium sulfate precipitation, and purified using size exclusion chromatography at a yield of ∼290 mg/L of culture. Secondary structure analysis of the purified rMcnapin revealed it to be predominantly α-helical with minimal β strand content. CD spectroscopic and fluorescence spectroscopic analyses revealed the rMcnapin to be stable at a wide range of temperatures and pH. The rMcnapin exhibited antifungal activity against Trichoderma viride with an IC50 of ∼3.7 μg/ml and trypsin inhibitor activity with an IC50 of 4.2 μM. Thus, large amounts of homogenous preparations of the biologically active rMcnapin could be obtained at shake flask level, which is otherwise difficult from its natural source.

Low cost production of perdeuterated biomass using methylotrophic yeasts

International Nuclear Information System (INIS)

Haon, S.; Auge, S.; Tropis, M.; Milon, A.; Lindley, N.D.

1993-01-01

Three strains of methylotropic yeasts, Candida boidinii, Pichia angusta (previously Hansenula polymorpha) and Pichia pastoris, were studied for their capacity to grow on methanol in deuterated media. Growth rates, determined relative to the extent of deuteration of water and/or methanol, showed that water deuteration was the major limiting factor. After adaptation to deuterium by progressive transfer through media of increasing deuteration, growth rates were diminished relative to those obtained on hydrogenated media of identical salts composition: the two Pichia species retained the highest growth rates in the full deuterated medium. Perdeuterated biomass (16 g) was obtained in a 1 liter fed-batch fermentation and the extent of deuteration of isolated ergosterol has been shown to be 97.5% by mass spectrometric analysis. (Author)

Radiosensitivity of Saccharomyces cerevisiae W303-1A and BY4741 Strains

Energy Technology Data Exchange (ETDEWEB)

Park, Ji Young; Kim, Jin Kyu [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Nili, Mohammad [Dawnesh Radiation Research Institute, Barcelona (Spain)

2011-05-15

Saccharomyces cerevisiae, a simple eukaryotic cell, has been widely used as a model for all eukaryotes including humans for the study of fundamental cellular processes such as DNA replication, DNA recombination, cell cycle, cell division and metabolism. Numerous laboratory strains are used in yeast research. Most of the mutants have been derived from the two widely used laboratory strains W303-1A and BY4741. While BY4741 is a derivative of S288C, used in the systematic sequencing of the S. cerevisiae genome, strains with a W303 background serve in many physiological and biochemical studies. It was found in a recent study that W303-1A contains a mutant allele of YBP1, ybp1-1, encoding four amino acid substitutions, that results in increased peroxide sensitivity. Mutation of ybp1-1 is not a complete loss of function allele as it is more resistant to peroxides than the knock-out mutant. Ybp1 is required for oxidation of specific cysteine residues of the transcription factor Yap1p resulting in the nuclear localization of Yap1p in response to stress. Ionizing radiation (IR) can produce highly reactive hydroxyl radicals through the decomposition of cellular water, such as superoxide anion radical, hydrogen peroxide, hydroxyl radical. These reactive oxygen species (ROS) can cause wide-ranging cellular damage, including DNA double-strand breaks (DSBs), lipid peroxidation, and protein modification. Also, ROS produced by IR cause oxidative stress. Detoxification enzymes are activated for ROS scavenging against oxidative stress. Also, antioxidants are used for detoxification of ROS and reduction of oxidative damage. NAC, one of the antioxidants, is a precursor for glutathione (GSH). The aim of the present study was to compare the differences in radiosensitivity associated cell viability between the two strains. Also, effect of NAC against IR on cell protection was investigated

Fine-Tuning Strain and Electronic Activation of Strain-Promoted 1,3-Dipolar Cycloadditions with Endocyclic Sulfamates in SNO-OCTs.

Science.gov (United States)

Burke, Eileen G; Gold, Brian; Hoang, Trish T; Raines, Ronald T; Schomaker, Jennifer M

2017-06-14

The ability to achieve predictable control over the polarization of strained cycloalkynes can influence their behavior in subsequent reactions, providing opportunities to increase both rate and chemoselectivity. A series of new heterocyclic strained cyclooctynes containing a sulfamate backbone (SNO-OCTs) were prepared under mild conditions by employing ring expansions of silylated methyleneaziridines. SNO-OCT derivative 8 outpaced even a difluorinated cyclooctyne in a 1,3-dipolar cycloaddition with benzylazide. The various orbital interactions of the propargylic and homopropargylic heteroatoms in SNO-OCT were explored both experimentally and computationally. The inclusion of these heteroatoms had a positive impact on stability and reactivity, where electronic effects could be utilized to relieve ring strain. The choice of the heteroatom combinations in various SNO-OCTs significantly affected the alkyne geometries, thus illustrating a new strategy for modulating strain via remote substituents. Additionally, this unique heteroatom activation was capable of accelerating the rate of reaction of SNO-OCT with diazoacetamide over azidoacetamide, opening the possibility of further method development in the context of chemoselective, bioorthogonal labeling.

Genotyping of Yersinia enterocolitica biotype 1A strains from clinical and nonclinical origins by pulsed-field gel electrophoresis.

Science.gov (United States)

Campioni, Fábio; Falcão, Juliana P

2014-06-01

Yersinia enterocolitica biotype 1A (B1A) strains are considered mainly nonpathogenic. However, some studies considered strains of this biotype to be the causal agents of infections in humans and animals. In South America, there are no studies that have compared clinical and nonclinical strains of B1A typed by pulsed-field gel electrophoresis (PFGE) and none that have compared the capability of different enzymes on typing these strains. This study typed 51 Y. enterocolitica B1A strains isolated in Brazil and Chile by PFGE, testing the enzymes XbaI, NotI, and XhoI. The resulting dendrograms discriminated the strains in 47, 40, and 49 pulsotypes generated by the cleavage with the enzymes XbaI, NotI, and XhoI, respectively. The majority of the strains were grouped independently of their clinical or nonclinical origins. The high discriminatory power of PFGE confirmed the heterogeneity of B1A strains but could not divide the strains studied into clusters that differed in the frequency of some virulence genes as observed in studies using other methodologies.

Membrane-aerated biofilm reactor for the removal of 1,2-dichloroethane by Pseudomonas sp. strain DCA1.

Science.gov (United States)

Hage, J C; Van Houten, R T; Tramper, J; Hartmans, S

2004-06-01

A membrane-aerated biofilm reactor (MBR) with a biofilm of Pseudomonas sp. strain DCA1 was studied for the removal of 1,2-dichloroethane (DCA) from water. A hydrophobic membrane was used to create a barrier between the liquid and the gas phase. Inoculation of the MBR with cells of strain DCA1 grown in a continuous culture resulted in the formation of a stable and active DCA-degrading biofilm on the membrane. The maximum removal rate of the MBR was reached at a DCA concentration of approximately 80 micro M. Simulation of the DCA fluxes into the biofilm showed that the MBR performance at lower concentrations was limited by the DCA diffusion rate rather than by kinetic constraints of strain DCA1. Aerobic biodegradation of DCA present in anoxic water could be achieved by supplying oxygen solely from the gas phase to the biofilm grown on the liquid side of the membrane. As a result, direct aeration of the water, which leads to undesired coagulation of iron oxides, could be avoided.

Clonal relationship among Vibrio cholerae O1 El Tor strains isolated in Somalia.

Science.gov (United States)

Scrascia, Maria; Pugliese, Nicola; Maimone, Francesco; Mohamud, Kadigia A; Grimont, Patrick A D; Materu, Sadiki F; Pazzani, Carlo

2009-03-01

One hundred and three Vibrio cholerae O1 strains, selected to represent the cholera outbreaks which occurred in Somalia in 1998-1999, were characterized by random amplified polymorphic DNA patterns, ribotyping, and antimicrobial susceptibility. All strains showed a unique amplified DNA pattern and 2 closely related ribotypes (B5a and B8a), among which B5a was the more frequently identified. Ninety-one strains were resistant to ampicillin, chloramphenicol, spectinomycin, streptomycin, sulfamethoxazole, and trimethoprim, conferred, except for spectinomycin, by a conjugative plasmid IncC. These findings indicated that the group of strains active in Somalia in the late 1990s had a clonal origin.

Tbc1d1 mutation in lean mouse strain confers leanness and protects from diet-induced obesity

DEFF Research Database (Denmark)

Chadt, Alexandra; Leicht, Katja; Deshmukh, Atul

2008-01-01

We previously identified Nob1 as a quantitative trait locus for high-fat diet-induced obesity and diabetes in genome-wide scans of outcross populations of obese and lean mouse strains. Additional crossbreeding experiments indicated that Nob1 represents an obesity suppressor from the lean Swiss Jim...... Lambert (SJL) strain. Here we identify a SJL-specific mutation in the Tbc1d1 gene that results in a truncated protein lacking the TBC Rab-GTPase-activating protein domain. TBC1D1, which has been recently linked to human obesity, is related to the insulin signaling protein AS160 and is predominantly...... and reduced glucose uptake in isolated skeletal muscle. Our data strongly suggest that mutation of Tbc1d1 suppresses high-fat diet-induced obesity by increasing lipid use in skeletal muscle....

Phylogenetic reconstruction of the Legionella pneumophila Philadelphia-1 laboratory strains through comparative genomics.

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Chitong Rao

Full Text Available Over 20 years ago, two groups independently domesticated Legionella pneumophila from a clinical isolate of bacteria collected during the first recognized outbreak of Legionnaires' disease (at the 1976 American Legion's convention in Philadelphia. These two laboratory strains, JR32 and Lp01, along with their derivatives, have been disseminated to a number of laboratories around the world and form the cornerstone of much of the research conducted on this important pathogen to date. Nevertheless, no exhaustive examination of the genetic distance between these strains and their clinical progenitor has been performed thus far. Such information is of paramount importance for making sense of several phenotypic differences observed between these strains. As environmental replication of L. pneumophila is thought to exclusively occur within natural protozoan hosts, retrospective analysis of the domestication and axenic culture of the Philadelphia-1 progenitor strain by two independent groups also provides an excellent opportunity to uncover evidence of adaptation to the laboratory environment. To reconstruct the phylogenetic relationships between the common laboratory strains of L. pneumophila Philadelphia-1 and their clinical ancestor, we performed whole-genome Illumina resequencing of the two founders of each laboratory lineage: JR32 and Lp01. As expected from earlier, targeted studies, Lp01 and JR32 contain large deletions in the lvh and tra regions, respectively. By sequencing additional strains derived from Lp01 (Lp02 and Lp03, we retraced the phylogeny of these strains relative to their reported ancestor, thereby reconstructing the evolutionary dynamics of each laboratory lineage from genomic data.

Effect of ratchet strain on fatigue and creep–fatigue strength of Mod.9Cr–1Mo steel

International Nuclear Information System (INIS)

Ando, Masanori; Isobe, Nobuhiro; Kikuchi, Koichi; Enuma, Yasuhiro

2012-01-01

Highlights: ► Uniaxial fatigue and creep–fatigue tests with superimposed strain were performed. ► Variety of superimposed strain were applied as ratchet strain in the tests. ► Effect of superimposed strain on fatigue and creep–fatigue life is negligible. ► A cyclic softening character reducing the effect of superimposed strain. - Abstract: The effect of ratcheting deformation on fatigue and creep–fatigue life in Mod.9Cr–1Mo steel was investigated. Uniaxial fatigue and creep–fatigue testing with superimposed strain were performed to evaluate the effect of ratcheting deformation on the failure cycle. In a series of tests, a specific amount of superimposed strain was accumulated in each cycle. The accumulated strain as ratcheting deformation, cycles to reach the accumulated strain, and test temperatures were varied in the tests. In the fatigue tests with superimposed strain at 550 °C, slight reductions of failure lives were observed. All of the numbers of cycles to failure in the fatigue tests with superimposed strain were within a factor of 1.5 of that of the fatigue test without superimposed strain at 550 °C. The apparent relationship between failure cycles and testing parameters was not observed. In fatigue tests with superimposed strain at 550 °C, maximum mean stress was insignificant and generated in early cycles because Mod.9Cr–1Mo steel exhibits cyclic softening characteristics. It was assumed that suppression of mean stress generation by cyclic softening reduces the effect of ratcheting strain. Conversely, failure lives were increased by accumulated strain in the test conducted at 450 °C because of stress–strain hysteresis loop shrinkage caused by cyclic softening induced by the accumulated strain. In the creep–fatigue tests with superimposed strain, test results indicated that the accumulated stain was negligible. It was concluded that the effect of ratcheting deformation on fatigue and creep–fatigue life is negligible as long

Serological characterization of Actinobacillus pleuropneumoniae biotype 1 strains antigenically related to both serotypes 2 and 7

DEFF Research Database (Denmark)

Nielsen, R.; Andresen, Lars Ole; Plambeck, Tamara

1996-01-01

Nine Danish Actinobacillus pleuropneumoniae biotype 1 isolates were shown by latex agglutination and indirect haemagglutination to possess capsular polysaccharide epitopes identical to those of serotype 2 strain 1536 (reference strain of serotype 2) and strain 4226 (Danish serotype 2 strain). Imm...... in the LPS of strains 1536 and 7317 were revealed. Since an antigenic determinant specific for the 9 isolates could not be demonstrated with the methods used, the strains are proposed to be designated K2:O7....

ABC Transporter for Corrinoids in Halobacterium sp. Strain NRC-1†

OpenAIRE

Woodson, Jesse D.; Reynolds, April A.; Escalante-Semerena, Jorge C.

2005-01-01

We report evidence for the existence of a putative ABC transporter for corrinoid utilization in the extremely halophilic archaeon Halobacterium sp. strain NRC-1. Results from genetic and nutritional analyses of Halobacterium showed that mutants with lesions in open reading frames (ORFs) Vng1370G, Vng1371Gm, and Vng1369G required a 105-fold higher concentration of cobalamin for growth than the wild-type or parent strain. The data support the conclusion that these ORFs encode orthologs of the b...

Recent advances in echocardiography: strain and strain rate imaging [version 1; referees: 3 approved

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Oana Mirea

2016-04-01

Full Text Available Deformation imaging by echocardiography is a well-established research tool which has been gaining interest from clinical cardiologists since the introduction of speckle tracking. Post-processing of echo images to analyze deformation has become readily available at the fingertips of the user. New parameters such as global longitudinal strain have been shown to provide added diagnostic value, and ongoing efforts of the imaging societies and industry aimed at harmonizing methods will improve the technique further. This review focuses on recent advances in the field of echocardiographic strain and strain rate imaging, and provides an overview on its current and potential future clinical applications.

Enterobacterial repetitive intergenic consensus sequences and the PCR to generate fingerprints of genomic DNAs from Vibrio cholerae O1, O139, and non-O1 strains.

Science.gov (United States)

Rivera, I G; Chowdhury, M A; Huq, A; Jacobs, D; Martins, M T; Colwell, R R

1995-08-01

Enterobacterial repetitive intergenic consensus (ERIC) sequence polymorphism was studied in Vibrio Cholerae strains isolated before and after the cholera epidemic in Brazil (in 1991), along with epidemic strains from Peru, Mexico, and India, by PCR. A total of 17 fingerprint patterns (FPs) were detected in the V. cholerae strains examined; 96.7% of the toxigenic V. cholerae O1 strains and 100% of the O139 serogroup strains were found to belong to the same FP group comprising four fragments (FP1). The nontoxigenic V. cholerae O1 also yielded four fragments but constituted a different FP group (FP2). A total of 15 different patterns were observed among the V. cholerae non-O1 strains. Two patterns were observed most frequently for V. cholerae non-01 strains, 25% of which have FP3, with five fragments, and 16.7% of which have FP4, with two fragments. Three fragments, 1.75, 0.79, and 0.5 kb, were found to be common to both toxigenic and nontoxigenic V. cholerae O1 strains as well as to group FP3, containing V. cholerae non-O1 strains. Two fragments of group FP3, 1.3 and 1.0 kb, were present in FP1 and FP2 respectively. The 0.5-kb fragment was common to all strains and serogroups of V. cholerae analyzed. It is concluded from the results of this study, based on DNA FPs of environmental isolates, that it is possible to detect an emerging virulent strain in a cholera-endemic region. ERIC-PCR constitutes a powerful tool for determination of the virulence potential of V. cholerae O1 strains isolated in surveillance programs and for molecular epidemiological investigations.

Construction of uricase-overproducing strains of Hansenula polymorpha and its application as biological recognition element in microbial urate biosensor

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Schuhmann Wolfgang

2011-05-01

Full Text Available Abstract Background The detection and quantification of uric acid in human physiological fluids is of great importance in the diagnosis and therapy of patients suffering from a range of disorders associated with altered purine metabolism, most notably gout and hyperuricaemia. The fabrication of cheap and reliable urate-selective amperometric biosensors is a challenging task. Results A urate-selective microbial biosensor was developed using cells of the recombinant thermotolerant methylotrophic yeast Hansenula polymorpha as biorecognition element. The construction of uricase (UOX producing yeast by over-expression of the uricase gene of H. polymorpha is described. Following a preliminary screening of the transformants with increased UOX activity in permeabilized yeast cells the optimal cultivation conditions for maximal UOX yield namely a 40-fold increase in UOX activity were determined. The UOX producing cells were coupled to horseradish peroxidase and immobilized on graphite electrodes by physical entrapment behind a dialysis membrane. A high urate selectivity with a detection limit of about 8 μM was found. Conclusion A strain of H. polymorpha overproducing UOX was constructed. A cheap urate selective microbial biosensor was developed.

Relaxation of a strained 3C-SiC(1 1 1) thin film on silicon by He+ and O+ ion beam defect engineering

International Nuclear Information System (INIS)

Häberlen, M.; Murphy, B.; Stritzker, B.; Lindner, J.K.N.

2012-01-01

In this paper we report on the successful reduction of tensile strain in a thin strained ion-beam synthesized 3C-SiC(1 1 1) layer on silicon. The creation of a near-interface defect structure consisting of nanometric voids and stacking fault type defects by He ion implantation and subsequent annealing yields significant relaxation in the top SiC film. The microstructure of the defect layer is studied by transmission electron microscopy, and the strain state of the 3C-SiC layer was studied by high-resolution X-ray diffraction in a parallel beam configuration. Typical process conditions for the growth of GaN films on the SiC layer were emulated by high temperature treatments in a rapid thermal annealer or a quartz tube furnace. It is found that prolonged annealing at high temperatures leads to ripening of the voids and to a weaker reduction of the tensile strain. It is shown that this problem can be overcome by the co-implantation of oxygen ions to form highly thermally stable void/extended defect structures.

Strain Tuning of the Charge Density Wave in Monolayer and Bilayer 1T-TaS2

KAUST Repository

Gan, Liyong

2015-12-07

By first-principles calculations, we investigate the strain effects on the charge density wave states of monolayer and bilayer 1T-TaS2. The modified stability of the charge density wave in the monolayer is understood in terms of the strain dependent electron localization, which determines the distortion amplitude. On the other hand, in the bilayer the effect of strain on the interlayer interaction is also crucial. The rich phase diagram under strain opens new venues for applications of 1T-TaS2. We interpret the experimentally observed insulating state of bulk 1T-TaS2 as inherited from the monolayer by effective interlayer decoupling.

Characterization of Ni-tolerant methylobacteria associated with the hyperaccumulating plant Thlaspi goesingense and description of Methylobacterium goesingense sp. nov.

Science.gov (United States)

Idris, Rughia; Kuffner, Melanie; Bodrossy, Levente; Puschenreiter, Markus; Monchy, Sebastien; Wenzel, Walter W; Sessitsch, Angela

2006-12-01

Various pink-pigmented facultative methylotrophic (PPFM) bacteria (strains iEII3, iEIV1, iEI6, iEII1, iEIII3 iEIII4, iEIII5, iRII1, iRII2, iRIII1, iRIV1 and iRIV2) were obtained from the rhizosphere and endosphere of hyperaccumulating plant Thlaspi goesingense grown in Redschlag, Austria [R. Idris, R. Trifonova, M. Puschenreiter, W.W. Wenzel, A. Sessitsch, Bacterial communities associated with flowering plants of the Ni hyperaccumulator Thlaspi goesingense, Appl. Environ. Microbiol. 70 (2004) 2667-2677]. Due to their unexpected diversity, abundance and nickel tolerance they were further characterized by detailed 16S rRNA gene analysis, DNA-DNA hybridization, fatty acid analysis, heavy metal tolerance, screening for known Ni resistance genes and phenotypic analysis. These strains were found to exhibit different multiple heavy metal resistance characteristics to Ni, Cd, Co, Zn and Cr. On the basis of their physiological and genotypic properties, strains could be grouped with Methylobacterium extorquens and M. mesophilicum. One endophyte, strain iEII3, was found to belong to a novel species for which the name M. goesingense is proposed.

Glucose and maltose metabolism in MIG1-disrupted and MAL-constitutive strains of Saccharomyces cerevisiae

DEFF Research Database (Denmark)

Klein, Christopher; Olsson, Lisbeth; Rønnow, B

1997-01-01

in a mixed glucose-maltose medium revealed that the MAL-constitutive strains were more alleviated than the single MIG1-disrupted transformant. While all transformants exhibited higher maximum specific growth rates (0.24-0.25 h(-1)) in glucose-maltose mixtures than the wild type strain (0.20 h(-1)), the MAL-constitutive...

In Vivo Characterisation of Five Strains of Bovine Viral Diarrhoea Virus 1 (Subgenotype 1c

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Rebecca K. Ambrose

2018-01-01

Full Text Available Bovine viral diarrhoea virus 1 (BVDV-1 is strongly associated with several important diseases of cattle, such as bovine respiratory disease, diarrhoea and haemoragic lesions. To date many subgenotypes have been reported for BVDV-1, currently ranging from subgenotype 1a to subgenotype 1u. While BVDV-1 has a world-wide distribution, the subgenotypes have a more restricted geographical distribution. As an example, BVDV-1 subgenotypes 1a and 1b are frequently detected in North America and Europe, while the subgenotype 1c is rarely detected. In contrast, BVDV-1 subgenotype 1c is by far the most commonly reported in Australia. Despite this, uneven distribution of the biological importance of the subgenotypes remains unclear. The aim of this study was to characterise the in vivo properties of five strains of BVDV-1 subgenotype 1c in cattle infection studies. No overt respiratory signs were reported in any of the infected cattle regardless of strain. Consistent with other subgenotypes, transient pyrexia and leukopenia were commonly identified, while thrombocytopenia was not. The quantity of virus detected in the nasal secretions of transiently infected animals suggested the likelihood of horizontal transmission was very low. Further studies are required to fully understand the variability and importance of the BVDV-1 subgenotype 1c.

Metagenomic survey of methanesulfonic acid (MSA catabolic genes in an Atlantic Ocean surface water sample and in a partial enrichment

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Ana C. Henriques

2016-10-01

Full Text Available Methanesulfonic acid (MSA is a relevant intermediate of the biogeochemical cycle of sulfur and environmental microorganisms assume an important role in the mineralization of this compound. Several methylotrophic bacterial strains able to grow on MSA have been isolated from soil or marine water and two conserved operons, msmABCD coding for MSA monooxygenase and msmEFGH coding for a transport system, have been repeatedly encountered in most of these strains. Homologous sequences have also been amplified directly from the environment or observed in marine metagenomic data, but these showed a base composition (G + C content very different from their counterparts from cultivated bacteria. The aim of this study was to understand which microorganisms within the coastal surface oceanic microflora responded to MSA as a nutrient and how the community evolved in the early phases of an enrichment by means of metagenome and gene-targeted amplicon sequencing. From the phylogenetic point of view, the community shifted significantly with the disappearance of all signals related to the Archaea, the Pelagibacteraceae and phylum SAR406, and the increase in methylotroph-harboring taxa, accompanied by other groups so far not known to comprise methylotrophs such as the Hyphomonadaceae. At the functional level, the abundance of several genes related to sulfur metabolism and methylotrophy increased during the enrichment and the allelic distribution of gene msmA diagnostic for MSA monooxygenase altered considerably. Even more dramatic was the disappearance of MSA import-related gene msmE, which suggests that alternative transporters must be present in the enriched community and illustrate the inadequacy of msmE as an ecofunctional marker for MSA degradation at sea.

New spectrophotometric/chemometric assisted methods for the simultaneous determination of imatinib, gemifloxacin, nalbuphine and naproxen in pharmaceutical formulations and human urine

Science.gov (United States)

Belal, F.; Ibrahim, F.; Sheribah, Z. A.; Alaa, H.

2018-06-01

In this paper, novel univariate and multivariate regression methods along with model-updating technique were developed and validated for the simultaneous determination of quaternary mixture of imatinib (IMB), gemifloxacin (GMI), nalbuphine (NLP) and naproxen (NAP). The univariate method is extended derivative ratio (EDR) which depends on measuring every drug in the quaternary mixture by using a ternary mixture of the other three drugs as divisor. Peak amplitudes were measured at 294 nm, 250 nm, 283 nm and 239 nm within linear concentration ranges of 4.0-17.0, 3.0-15.0, 4.0-80.0 and 1.0-6.0 μg mL-1 for IMB, GMI, NLP and NAB, respectively. Multivariate methods adopted are partial least squares (PLS) in original and derivative mode. These models were constructed for simultaneous determination of the studied drugs in the ranges of 4.0-8.0, 3.0-11.0, 10.0-18.0 and 1.0-3.0 μg mL-1 for IMB, GMI, NLP and NAB, respectively, by using eighteen mixtures as a calibration set and seven mixtures as a validation set. The root mean square error of predication (RMSEP) were 0.09 and 0.06 for IMB, 0.14 and 0.13 for GMI, 0.07 and 0.02 for NLP and 0.64 and 0.27 for NAP by PLS in original and derivative mode, respectively. Both models were successfully applied for analysis of IMB, GMI, NLP and NAP in their dosage forms. Updated PLS in derivative mode and EDR were applied for determination of the studied drugs in spiked human urine. The obtained results were statistically compared with those obtained by the reported methods giving a conclusion that there is no significant difference regarding accuracy and precision.

Deinococcus radiodurans strain R1 contains N6-methyladenine in its genome

International Nuclear Information System (INIS)

Prasad, Bhaskar Jyoti; Sabnis, Ketaki; Deobagkar, Deepti D.; Deobagkar, Dileep N.

2005-01-01

Methylation of DNA is known to be involved in DNA repair mechanisms in bacteria. Deinococcus radiodurans strain R1 on exposure to high radiation undergoes significant DNA damage, which is repaired without mutations. However, the presence of modified nucleotides has not been reported in its genome. We report here the detection of N6-methyladenine in the genome of D. radiodurans strain R1 using immunochemical techniques. This N6-methyladenine is not a part of GATC restriction-modification system. D. radiodurans cell extract also exhibited a DNA adenine methyltransferase activity which was reduced in the early post-irradiation recovery phase

Genomic Changes in an Attenuated ZB Strain of Foot-and-Mouth Disease Virus Serotype Asia1 and Comparison with Its Virulent Parental Strain

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Aiguo Xin

2014-01-01

Full Text Available The molecular basis of attenuation of foot-and-mouth disease virus (FMDV serotype Asia1 ZB strain remains unknown. To understand the genetic changes of attenuation, we compared the entire genomes of three different rabbit-passaged attenuated ZB strains (ZB/CHA/58(att, ZBRF168, and ZBRF188 and their virulent parental strains (ZBCF22 and YNBS/58. The results showed that attenuation may be brought about by 28 common amino acid substitutions in the coding region, with one nucleotide point mutation in the 5′-untranslated region (5′-UTR and another one in the 3′-UTR. In addition, a total of 21 nucleotides silent mutations had been found after attenuation. These substitutions, alone or in combination, may be responsible for the attenuated phenotype of the ZB strain in cattle. This will contribute to elucidation of attenuating molecular basis of the FMDV ZB strain.

Preparation of strained axially chiral (1,5)naphthalenophanes by photo-dehydro-Diels-Alder reaction.

Science.gov (United States)

Wessig, Pablo; Matthes, Annika

2011-03-02

The preparation of 10 (1,5)naphthalenophanes (10a-j) by photo-dehydro-Diels-Alder (PDDA) reaction is described. Owing to hindered rotation around the biaryl axis, compounds 10 are axially chiral and the separation of enantiomers by chiral HPLC was demonstrated in three cases (10a,b,e). The absolute configuration of the isolated enantiomers could be unambiguously determined by comparison of calculated and measured circular dichroism (CD) spectra. Furthermore, we analyzed ring strain phenomena of (1,5)naphthalenophanes 10. Depending on the length of the linker units, one can distinguish three classes of naphthalenophanes. Compounds 10a-c are highly strained (E(STR) = 7-31 kcal/mol), and the strain is caused by small bond angles in the linker unit and deformation of the naphthalene moiety. Another type of strain is observed if the linker unit becomes relatively long (10g,h) originating from transannular interactions and is comparable with the well-known strain of medium sized rings. The naphthalenophanes 10d-f with a linker length of 10-14 atoms are only marginally strained. To clearly discriminate the different sources of strain, we defined two geometrical parameters (average central dihedral angle δ(C) and naphthalene thickness D(N)) and demonstrated that they are well-suited to indicate naphthalene deformation of our naphthalenophanes 10 as well as of ten model naphthalenophanes (I-X) with different linker lengths and linking positions.

The genomic diversity and stability of field strains of Suid herpesvirus 1 (Aujeszky's disease virus)

DEFF Research Database (Denmark)

Christensen, Laurids Siig; Sørensen, K. J.

1991-01-01

The genomic diversity among isolates of suid herpesvirus 1 (SHV-1) collected in the same herd and among clones from the same isolate was studied by restriction fragment pattern (RFP) analysis using BamHI. Tentatively defining a field strain as a transmissible entity, it was concluded that strains...

Exploring strain-promoted 1,3-dipolar cycloadditions of end functionalized polymers

NARCIS (Netherlands)

Ledin, Petr A; Kolishetti, Nagesh; Hudlikar, Manish S; Boons, Geert-Jan

2014-01-01

Strain-promoted 1,3-dipolar cycloaddition of cyclooctynes with 1,3-dipoles such as azides, nitrones, and nitrile oxides, are of interest for the functionalization of polymers. In this study, we have explored the use of a 4-dibenzocyclooctynol (DIBO)-containing chain transfer agent in reversible

76 FR 55268 - Chromobacterium subtsugae Strain PRAA4-1T

Science.gov (United States)

2011-09-07

... (irritation symptoms cleared by 24 hours; Toxicity Category IV). 9. Dermal sensitization--guinea pig... that Chromobacterium subtsugae strain PRAA4-1\\T\\ was not a dermal sensitizer to guinea pigs. IV... production (NAICS code 111). Animal production (NAICS code 112). Food manufacturing (NAICS code 311...

The Information and Motivation and Behavioral Skills Model of ART Adherence among HIV-Positive Adults in Mexico.

Science.gov (United States)

Santillán Torres Torija, Carolina; Villagrán Vázquez, Gabina; Robles Montijo, Silvia Susana; de Lourdes Eguiluz Romo, Luz

2015-01-01

Middle-income countries are in need of research that uses theoretical-based models to assess factors that predict adherence to antiretroviral therapy (ART) and help in the design, implementation, and evaluation of interventions for nonadherent populations. In Mexico, the Information and Motivation and Behavioral Skills (IMB) Model of ART Adherence constructs is useful in describing and predicting adherence behaviors in various samples but has not been articulated to people living with HIV (PLWH) on ART. The aim of this was to characterize the IMB core constructs and identify correlates of ART adherence in an HIV-positive clinic sample in Mexico. A convenience sample of 109 HIV-positive patients attending their monthly visits at a local public hospital were interviewed with the Spanish version of the LifeWindows IMB ART Adherence Questionnaire (LW-IMB-AAQ) as well as a sociodemographic questionnaire. All participants were recruited from a hospital-based outpatient clinical care site. Partial confirmation of the relationships proposed by the IMB Model of ART Adherence was found. As predicted by the model, only behavioral skills had direct association with all measures of self-reported adherence, and motivation was associated with behavioral skills. Information did not demonstrate significant relations to either motivation or behavioral skills, nor did it directly associate with adherence. Self-reported adherence did not associate with CD4 counts, nor did any of the IMB model core constructs. Applicability of the IMB Model of ART Adherence in this setting is discussed. The IMB Model of ART Adherence offered promise in this population and could help tailor population-specific interventions to promote high rates of ART adherence. © The Author(s) 2015.

[EFFICIENCY OF INTRODUCING CAROTENE PRODUCING STRAINS BACILLUS SP. 1.1 AND B. AMYLOLIQUEFACIENS UCM B-5113 INTO THE CHIKENS DIET].

Science.gov (United States)

Nechypurenko, O O; Kharhota M A; Avdeeva, L V

2015-01-01

It was shown the efficiency of carotene producing strains Bacillus sp. 1.1 and B. amyloliquefaciens UCM B-5113 in the diet of chickens. Also it was detected the lowering of the quantitative content of bacterial genera Enterococcus, Staphylococcus, family Enterobacteriaceae in the gut after eating by chickens cross "H&N Brown Nick" fodder with strains Bacillus sp. 1.1 and B. amyloliquefaciens UCM B-5113 alone and in composition in quantities 1 x 10(10) CFU per 1 g of feed. On the 18th day after introduction of cultures Bacillus sp. 1.1, B. amyloliquefaciens UCM B-5113 and their composition in the diet of poultry we revealed the increasing of body weight by 21.6, 7.6 and 22.0%, respectively, comparesing to controls. Also due to Bacillus sp. 1.1 it was detected the restore of intestinal villous structures, tissues of spleen, liver and heart. We found the additive effect of the composition of the investigated strains of bacteria genus Bacillus to the chickens.

Copper tolerance in Frankia sp. strain EuI1c involves surface binding and copper transport.

Science.gov (United States)

Rehan, Medhat; Furnholm, Teal; Finethy, Ryan H; Chu, Feixia; El-Fadly, Gomaah; Tisa, Louis S

2014-09-01

Several Frankia strains have been shown to be copper-tolerant. The mechanism of their copper tolerance was investigated for Frankia sp. strain EuI1c. Copper binding was shown by binding studies. Unusual globular structures were observed on the surface of the bacterium. These globular structures were composed of aggregates containing many relatively smaller "leaf-like" structures. Scanning electron microscopy with energy-dispersive X-ray (SEM-EDAX) analysis of these structures indicated elevated copper and phosphate levels compared to the control cells. Fourier transform infrared spectroscopy (FTIR) analysis indicated an increase in extracellular phosphate on the cell surface of copper-stressed cells. Bioinformatics' analysis of the Frankia sp. strain EuI1c genome revealed five potential cop genes: copA, copZ, copC, copCD, and copD. Experiments with Frankia sp. strain EuI1c using qRT-PCR indicated an increase in messenger RNA (mRNA) levels of the five cop genes upon Cu(2+) stress. After 5 days of Cu(2+) stress, the copA, copZ, copC, copCD, and copD mRNA levels increased 25-, 8-, 18-, 18-, and 25-fold, respectively. The protein profile of Cu(2+)-stressed Frankia sp. strain EuI1c cells revealed the upregulation of a 36.7 kDa protein that was identified as FraEuI1c_1092 (sulfate-binding periplasmic transport protein). Homologues of this gene were only present in the genomes of the Cu(2+)-resistant Frankia strains (EuI1c, DC12, and CN3). These data indicate that copper tolerance by Frankia sp. strain EuI1c involved the binding of copper to the cell surface and transport proteins.

Unified inelastic constitutive equations incorporating dynamic strain aging for Mod. 9Cr-1Mo steel

International Nuclear Information System (INIS)

Yaguchi, Masatsugu; Takahashi, Yukio

1998-01-01

A unified constitutive model considering dynamic strain aging effect was developed in order to describe inelastic deformation behavior of the Mod. 9Cr-1Mo steel precisely. The inelastic behavior of the steel was summarized as follows. A rate dependent deformation was observed above 500degC, and there was no rate dependency under 400degC. However, stress relaxation behavior was observed even at rate independent temperature region. Further, a stress after relaxation depended on prior loading strain rate, and it showed a higher value as the strain rate was slow. A feature of the proposed constitutive model was that an applied stress consists of three stress components: a back stress, an overstress and an aging stress which corresponds to dynamics strain aging and shows a negative strain rate dependency. The aging stress was measured by strain rate change tests, and it showed larger values as the strain rates were slow and the temperatures were low. The backstress and the overstress were measured by strain dip tests. The backstress was approximately rate independent under 400degC, however it showed rate dependency above 500degC. The overstress showed larger values as the strain rates were fast and the temperatures were high. The material constants were determined systematically based on the measured values of each internal variable. In order to evaluate the validity of the constitutive model, numerical simulations were done for various inelastic deformation behavior of Mod. 9Cr-1Mo steel. The simulations agreed with experimental results very well in all cases. (author)

VNTR fingerprinting of Kluyveromyces marxianus strains WT, 7-1, and 8-1 by using different primer types to give best results in PCR and on electrophorese gel in order to find differentiation of the DNA of the yeast strains.

Science.gov (United States)

Using mutagenized Kluyveromyces marxianus strains (WT, 7-1, 8-1) we wish to find out the variable numbered tandem repeats (VNTR) of each of the DNA strains from the different mutagenized K. marxianus strains. To do this we used Phusion HF Buffer Pack to try and give a clear picture of the VNTR by u...

Analysing the dhaT gene in Colombian Clostridium sp. (Clostridia 1,3-propanediol-producing strains

Directory of Open Access Journals (Sweden)

Diana Milena Quilaguy-Ayure

2010-04-01

Full Text Available To analyze the dhaT gene, one of the genes responsible for the 1,3-propanediol (1,3-PD production, in two native Clostridiumstrains. Materials and methods: The dhaT gene was amplified by Polimerase Chain Reaction with specific primers designed fromClostridium butyricum VPI1718 operon. Bioinformatics tools like BLASTN, ORF finder, BLASTP and ClustalW were used to determinethe identity of the sequence and to assign a function. Results: DNA amplification products were obtained from Colombian Clostridium sp.native strains (IBUN 13A and IBUN 158B and the Clostridium butyricum DSM 2478 strain, which were sequenced. According to thebioinformatics analysis of the above sequences, a high degree of similarity was found with the dhaT gene of different bacterial species. Thehighest percentage of identity was obtained with the Clostridium butyricum VPI 1718 strain. Conclusion: knowledge of the physicalstructure of the 1,3-PD operon in native strains opens the way for developing genetic and metabolic engineering strategies for improvingprocesses productivity.

Aliphatic and aromatic hydrocarbons in tropical recent sediments of Campos dos Goytacazes, RJ, Brazil

Directory of Open Access Journals (Sweden)

Gomes Alexandre de O.

2003-01-01

Full Text Available Sediment samples from the Imbé, the Urubu and the Ururaí rivers and from Lake de Cima were studied. These sites are located in the county of Campos dos Goytacazes, Rio de Janeiro, Brazil. Aliphatic and aromatic fractions were analyzed by GC-FID and GC-MS in order to gather information on the degree of contamination by anthropogenic activities and other biogenic contributions. Concentrations of total aliphatic and aromatic hydrocarbons were 1.2, 2.8, 5.8 and 4.3 mug g-1 and 74, 30, 722 and 340 ng g-1 in the Imbé, Ururaí, Urubu rivers and Lake de Cima, respectively. The C20 highly branched isoprenoid alkane was identified in the Urubu sediment. There were no hopanes or steranes in any sample. Anthropogenic aromatic compounds, detected at trace levels, were observed only in the Imbé and in Lake de Cima (227 ng g-1. The fluoranthene/pyrene rate for Lake de Cima was 4.2, suggesting a combustion origin for the PAH. This data is consistent with the frequently sugar cane burning practice that occurs in this region. A greater input from higher plants was observed in the Urubu, Imbé and Lake de Cima sediments; on the other hand, the aquatic input predominates for Ururaí. In summary, Lake de Cima sediment is considered very slightly polluted, while the others are unpolluted.

Lanthanide-Dependent Regulation of Methanol Oxidation Systems in Methylobacterium extorquens AM1 and Their Contribution to Methanol Growth.

Science.gov (United States)

Vu, Huong N; Subuyuj, Gabriel A; Vijayakumar, Srividhya; Good, Nathan M; Martinez-Gomez, N Cecilia; Skovran, Elizabeth

2016-04-01

Methylobacterium extorquens AM1 has two distinct types of methanol dehydrogenase (MeDH) enzymes that catalyze the oxidation of methanol to formaldehyde. MxaFI-MeDH requires pyrroloquinoline quinone (PQQ) and Ca in its active site, while XoxF-MeDH requires PQQ and lanthanides, such as Ce and La. Using MeDH mutant strains to conduct growth analysis and MeDH activity assays, we demonstrate that M. extorquens AM1 has at least one additional lanthanide-dependent methanol oxidation system contributing to methanol growth. Additionally, the abilities of different lanthanides to support growth were tested and strongly suggest that both XoxF and the unknown methanol oxidation system are able to use La, Ce, Pr, Nd, and, to some extent, Sm. Further, growth analysis using increasing La concentrations showed that maximum growth rate and yield were achieved at and above 1 μM La, while concentrations as low as 2.5 nM allowed growth at a reduced rate. Contrary to published data, we show that addition of exogenous lanthanides results in differential expression from the xox1 and mxa promoters, upregulating genes in the xox1 operon and repressing genes in the mxa operon. Using transcriptional reporter fusions, intermediate expression from both the mxa and xox1 promoters was detected when 50 to 100 nM La was added to the growth medium, suggesting that a condition may exist under which M. extorquens AM1 is able to utilize both enzymes simultaneously. Together, these results suggest that M. extorquens AM1 actively senses and responds to lanthanide availability, preferentially utilizing the lanthanide-dependent MeDHs when possible. The biological role of lanthanides is a nascent field of study with tremendous potential to impact many areas in biology. Our studies demonstrate that there is at least one additional lanthanide-dependent methanol oxidation system, distinct from the MxaFI and XoxF MeDHs, that may aid in classifying additional environmental organisms as methylotrophs. Further

Biological treatment of closed landfill leachate treatment by using Brevibacillus panacihumi strain ZB1

Science.gov (United States)

Er, X. Y.; Seow, T. W.; Lim, C. K.; Ibrahim, Z.; Mat Sarip, S. H.

2018-04-01

Landfills are widely used for solid waste disposal due to cost effectiveness and ease of operation. Poor landfill management generally accompanied with production of toxic leachate. Leachate refers to heavily polluted liquid produced due to waste decomposition and rainwater percolation. Direct discharge of untreated leachate into the environment will lead to environmental degradation and health hazards. The aim of this study was to study the efficiency of leachate biological treatment by B. panacihumi strain ZB1. In this study, leachate wastewater was treated by B. panacihumi strain ZB1 via 42-days anaerobic-aerobic treatment. Leachate characterization of both raw and treated samples was carried out based on ammonia nitrogen content, chemical oxygen demand (COD) and heavy metal content. Through leachate characterization, raw leachate carried high concentrations of ammonia nitrogen (1977 mg/L), COD (5320 mg/L) and certain heavy metals exceeding discharge standard. From this study, B. panacihumi strain ZB1 able to remove COD nearly 40%, ammonia nitrogen nearly 50% and different degrees of heavy metals from the leachate sample after combined anaerobic-aerobic treatment. As a result, B. panacihumi strain ZB1was expected to treat the leachate wastewater with certain treatment efficiency via combined anaerobic-aerobic treatment.

Human prostate supports more efficient replication of HIV-1 R5 than X4 strains ex vivo

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Denis Hélène

2008-12-01

Full Text Available Abstract Background In order to determine whether human prostate can be productively infected by HIV-1 strains with different tropism, and thus represent a potential source of HIV in semen, an organotypic culture of prostate from men undergoing prostatic adenomectomy for benign prostate hypertrophy (BPH was developed. The presence of potential HIV target cells in prostate tissues was investigated using immunohistochemistry. The infection of prostate explants following exposures with HIV-1 R5, R5X4 and X4 strains was analyzed through the measure of RT activity in culture supernatants, the quantification of HIV DNA in the explants and the detection of HIV RNA+ cells in situ. Results The overall prostate characteristics were retained for 21/2 weeks in culture. Numerous potential HIV-1 target cells were detected in the prostate stroma. Whilst HIV-1 R5SF162 strain consistently productively infected prostatic T lymphocytes and macrophages, the prototypic X4IIIB strain and a primary R5X4 strain showed less efficient replication in this organ. Conclusion The BPH prostate is a site of HIV-1 R5 replication that could contribute virus to semen. A limited spreading of HIV-1 X4 and R5X4 in this organ could participate to the preferential sexual transmission of HIV-1 R5 strains.

Metagenome-Assembled Genome Sequences of Acetobacterium sp. Strain MES1 and Desulfovibrio sp. Strain MES5 from a Cathode-Associated Acetogenic Microbial Community.

Science.gov (United States)

Ross, Daniel E; Marshall, Christopher W; May, Harold D; Norman, R Sean

2017-09-07

Draft genome sequences of Acetobacterium sp. strain MES1 and Desulfovibrio sp. strain MES5 were obtained from the metagenome of a cathode-associated community enriched within a microbial electrosynthesis system (MES). The draft genome sequences provide insight into the functional potential of these microorganisms within an MES and a foundation for future comparative analyses. Copyright © 2017 Ross et al.

High-resolution melt PCR analysis for rapid identification of Chlamydia abortus live vaccine strain 1B among C. abortus strains and field isolates.

Science.gov (United States)

Vorimore, Fabien; Cavanna, Noémie; Vicari, Nadia; Magnino, Simone; Willems, Hermann; Rodolakis, Annie; Siarkou, Victoria I; Laroucau, Karine

2012-09-01

We describe a novel high-resolution melt assay that clearly differentiates Chlamydia abortus live vaccine strain 1B from field C. abortus strains and field wild-type isolates based on previously described single nucleotide polymorphisms. This modern genotyping technique is inexpensive, easy to use, and less time-consuming than PCR-RFLP. Copyright © 2012 Elsevier B.V. All rights reserved.

Near-Isogenic Cry1F-Resistant Strain of Spodoptera frugiperda (Lepidoptera: Noctuidae) to Investigate Fitness Cost Associated With Resistance in Brazil.

Science.gov (United States)

Horikoshi, Renato J; Bernardi, Oderlei; Bernardi, Daniel; Okuma, Daniela M; Farias, Juliano R; Miraldo, Leonardo L; Amaral, Fernando S A; Omoto, Celso

2016-04-01

Field-evolved resistance to Cry1F maize in Spodoptera frugiperda (J.E. Smith) populations in Brazil was reported in 2014. In this study, to investigate fitness costs, we constructed a near-isogenic S. frugiperda-resistant strain (R-Cry1F) using Cry1F-resistant and Cry1F-susceptible strains sharing a close genetic background. A near-isogenic R-Cry1F strain was obtained by eight repeated backcrossings, each followed by sib-mating and selection among resistant and susceptible strains. Fitness cost parameters were evaluated by comparing the biological performance of resistant, susceptible, and heterozygous strains on artificial diet. Fitness parameters monitored included development time and survival rates of egg, larval, pupal, and egg-to-adult periods; sex ratio; adult longevity; timing of preoviposition, oviposition, and postoviposition; fecundity; and fertility. A fertility life table was also calculated. The near-isogenic R-Cry1F strain showed lower survival rate of eggs (32%), when compared with Sus and reciprocal crosses (41 and 55%, respectively). The number of R-Cry1F insects that completed the life cycle was reduced to ∼25%, compared with the Sus strain with ∼32% reaching the adult stage. The mean generation time (T) of R-Cry1F strain was ∼2 d shorter than R-Cry1F♂×Sus♀ and Sus strains. The reproductive parameters of R-Cry1F strain were similar to the Sus strain. However, fewer females were produced by R-Cry1F strain than R-Cry1F♀×Sus♂ and more females than R-Cry1F♂×Sus♀. In summary, no relevant fitness costs are observed in a near-isogenic Cry1F-resistant strain of S. frugiperda, indicating stability of resistance to Cry1F protein in Brazilian populations of this species in the absence of selection pressure.

Biodegradation of buprofezin by Rhodococcus sp. strain YL-1 isolated from rice field soil.

Science.gov (United States)

Li, Chao; Zhang, Ji; Wu, Zhi-Guo; Cao, Li; Yan, Xin; Li, Shun-Peng

2012-03-14

A buprofezin-degrading bacterium, YL-1, was isolated from rice field soil. YL-1 was identified as Rhodococcus sp. on the basis of the comparative analysis of 16S rDNA sequences. The strain could use buprofezin as the sole source of carbon and nitrogen for growth and was able to degrade 92.4% of 50 mg L(-1) buprofezin within 48 h in liquid culture. During the degradation of buprofezin, four possible metabolites, 2-tert-butylimino-3-isopropyl-1,3,5-thiadiazinan-4-one, N-tert-butyl-thioformimidic acid formylaminomethyl ester, 2-isothiocyanato-2-methyl-propane, and 2-isothiocyanato-propane, were identified using gas chromatography-mass spectrometry (GC-MS) analysis. The catechol 2,3-dioxygenase activity was strongly induced during the degradation of buprofezin. A novel microbial biodegradation pathway for buprofezin was proposed on the basis of these metabolites. The inoculation of soils treated with buprofezin with strain YL-1 resulted in a higher degradation rate than that observed in noninoculated soils, indicating that strain YL-1 has the potential to be used in the bioremediation of buprofezin-contaminated environments.

Effect of aflatoxin B1 on growth and enzymatic activity of a native strain of Bacillus sp

Directory of Open Access Journals (Sweden)

Alex Sáez Vega

2004-01-01

Full Text Available The effect of different aflatoxin B1 (AFAB1 concentrations on alkaline protease growth and enzymatic activity was evaluated; a native strain of alkalophilic Bacillus sp cultivated in CSL (Corn Steep Liquor was used. It was found that the effect of AFAB1 on the strain inhibited its growth and enzymatic activity to 1 ppm, showing that the strain is highly sensible to AFAB1, meaning that medium obtained f rom Colombian corn contaminated with this mycotoxin cannot be easily used. Concentrations less than 0.1 ppm did not affect growth and enzymatic activity. Key words: Bacillus, aflatoxin, alkaline proteases.

Strain-induced structural changes and chemical reactions. 1: Thermomechanical and kinetic models

International Nuclear Information System (INIS)

Levitas, V.I.; Nesterenko, V.F.; Meyers, M.A.

1998-01-01

Strain-induced chemical reactions were observed recently (Nesterenko et al) in experiments in the shear band in both Ti-Si and Nb-Si mixtures. Reactions can start in the solid state or after melting of at least one component. One of the aims is to find theoretically whether there are possible macroscopic mechanisms of mechanical intensification of the above and other chemical reactions due to plastic shear in the solid state. Continuum thermodynamical theory of structural changes with an athermal kinetics, which includes martensitic phase transformations, plastic strain-induced chemical reactions and polymorphic transformations, is developed at finite strains. The theory includes kinematics, criterion of structural change and extremum principle for determination of all unknown variable parameters for the case with neglected elastic strains. Thermodynamically consistent kinetic theory of thermally activated structural changes is suggested. The concept of the effective temperature is introduced which takes into account that temperature can vary significantly (on 1,000 K) during the chemical reactions under consideration. The theory will be applied in Part 2 of the paper for the description of chemical reactions in the shear band

(HN1) strain of Aspergillus niger

African Journals Online (AJOL)

login123

2016-09-26

Sep 26, 2016 ... olive oil) increased the production of lipase up to 20% in case of both the strains. The production of ... insoluble triacylglycerols to generate free fatty acids, mono and ... Two fermentation processes, including solid state.

Methylotroph cloning vehicle

Science.gov (United States)

Hanson, R.S.; Allen, L.N.

1989-04-25

A cloning vehicle comprising: a replication determinant effective for replicating the vehicle in a non-C[sub 1]-utilizing host and in a C[sub 1]-utilizing host; DNA effective to allow the vehicle to be mobilized from the non-C[sub 1]-utilizing host to the C[sub 1]-utilizing host; DNA providing resistance to two antibiotics to which the wild-type C[sub 1]-utilizing host is susceptible, each of the antibiotic resistance markers having a recognition site for a restriction endonuclease; a cos site; and a means for preventing replication in the C[sub 1]-utilizing host. The vehicle is used for complementation mapping as follows. DNA comprising a gene from the C[sub 1]-utilizing organism is inserted at the restriction nuclease recognition site, inactivating the antibiotic resistance marker at that site. The vehicle can then be used to form a cosmid structure to infect the non-C[sub 1]-utilizing (e.g., E. coli) host, and then conjugated with a selected C[sub 1]-utilizing mutant. Resistance to the other antibiotic by the mutant is a marker of the conjugation. Other phenotypical changes in the mutant, e.g., loss of an auxotrophic trait, is attributed to the C[sub 1] gene. The vector is also used to inactivate genes whose protein products catalyze side reactions that divert compounds from a biosynthetic pathway to a desired product, thereby producing an organism that makes the desired product in higher yields. 3 figs.

A novel growth-promoting microbe, Methylobacterium funariae sp. nov., isolated from the leaf surface of a common moss

OpenAIRE

Schauer, S; Kutschera, U

2011-01-01

Land plants (embryophytes) evolved in the presence of prokaryotic microbes. As a result, numerous mutually beneficial associations (symbioses) developed that can be analyzed using a variety of methods. Here we describe the isolation and characterization of a new pink-pigmented facultatively methylotrophic symbiotic bacterium of the genus Methylobacterium (laboratory strain F3.2) that was isolated from the gametophytic phylloids of the common cord moss Funaria hygrometrica Hedw. Plantlets were...

Cadophora malorum Cs-8-1 as a new fungal strain producing gibberellins isolated from Calystegia soldanella.

Science.gov (United States)

You, Young-Hyun; Yoon, Hyeokjun; Kang, Sang-Mo; Woo, Ju-Ri; Choo, Yeon-Sik; Lee, In-Jung; Shin, Jae-Ho; Kim, Jong-Guk

2013-07-01

Fourteen endophytic fungi with different colony morphologies were isolated from the roots of Calystegia soldanella. Endophytic fungi isolated from C. soldanella were identified by internal transcribed spacer (ITS) region. To verify plant growth promotion (PGP), culture filtrates of isolated endophytic fungi were treated in Waito-c rice (WR) and C. soldanella seedlings. Culture filtrates of Cs-8-1 fungal strain had advanced PGP activity. The presence of physiologically bioactive gibberellins (GA) GA(1) (1.213 ng ml(-1)), GA(3) (1.292 ng ml(-1)), GA(4) (3.6 ng ml(-1)), GA(7) (1.328 ng ml(-1)), other inactive GA(9) (0.796 ng ml(-1)) and GA(12) (0.417 ng ml(-1)), GA(20) (0.302 ng ml(-1)), GA(24) (1.351 ng ml(-1)), GA(34) (0.076 ng ml(-1)), and GA(53) (0.051 ng ml(-1)) in culture filtrates of Cs-8-1 fungal strain was detected. The Cs-8-1 fungal strain was confirmed as a producer of GAs. Molecular analysis of sequences showed high similarity of 99% to Cadophora malorum. Consequentially, the Cs-8-1 fungal strain was identified as a new C. malorum producing GAs. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Uticaj mesta ugradnje inercijalnog mernog bloka i akcelerometara na grešku u određivanju pozicije aviona / Size effect of the inertial measurement unit and inside IMU accelerometers on aircraft position error

Directory of Open Access Journals (Sweden)

Slobodan Janićijević

2003-03-01

Full Text Available U ovom članku analiziran je uticaj mesta ugradnje inercijalnog mernog bloka (IMB u avionu i mesta ugradnje akcelerometara u IMB na tačnost određivanja pozicije pomoću bes-platformskog inercijalnog navigacijskog sistema (BINS. Pokazano je da se ovi uticaji ne mogu uvek zanemariti. Izračunata je ukupna greška u određivanju pozicije aviona ako se IMB ugrađuje van centra rotacije aviona, a akcelerometri van centra IMB. Predložena je optimalna orijentacija akcelerometara u IMB-u, kako bi se minimizirao uticaj ugradnje akcelerometara van centra IMB na tačnost određivanja pozicije aviona. Predložen je i način kompenzacije greške. / This paper analyzes the mounting offset size effect of the inertial measurement unit (IMU in aircraft and accelerometers mounting offset size effect in the IMU on the accuracy of strap down inertial navigation system (SDINS. It is also shown that these effects cannot be always neglected. The total size effect error for the IMU has been the computed. An accelerometers optimum orientation inside the IMU has been proposed to minimize size effects on the accuracy of navigation parameters. A manner to compensate these size effects has been proposed as well.

Complete Genome Sequences of emm111 Type Streptococcus pyogenes Strain GUR, with Antitumor Activity, and Its Derivative Strain GURSA1 with an Inactivated emm Gene

DEFF Research Database (Denmark)

Suvorova, Maria A; Tsapieva, Anna N; Bak, Emilie Glad

2017-01-01

We present here the complete genome sequence of Streptococcus pyogenes type emm111 strain GUR, a throat isolate from a scarlet fever patient, which has been used to treat cancer patients in the former Soviet Union. We also present the complete genome sequence of its derivative strain GURSA1...

Murine FATP alleviates growth and biochemical deficiencies of yeast fat1Delta strains

DEFF Research Database (Denmark)

Dirusso, C C; Connell, E J; Færgeman, Nils J.

2000-01-01

following incubation of the cells with exogenous oleate. Expression of either Fat1p or murine FATP from a plasmid in a fat1Delta strain restored these phenotypic and biochemical deficiencies. Fat1p and FATP restored growth of fat1Delta cells in the presence of cerulenin and under hypoxic conditions....... Furthermore, fatty-acid transport was restored and was found to be chain length specific: octanoate, a medium-chain fatty acid was transported in a Fat1p- and FATP-independent manner while the long-chain fatty acids myristate, palmitate, and oleate required either Fat1p or FATP for maximal levels of transport....... Lignoceryl CoA synthetase activities were restored to wild-type levels in fat1Delta strains expressing either Fat1p or FATP. Fat1p or FATP also restored wild-type levels of beta-oxidation of exogenous long-chain fatty acids. These data show that Fat1p and FATP are functionally equivalent when expressed...

Isolation and characterization of a furfural-degrading bacterium Bacillus cereus sp. strain DS1.

Science.gov (United States)

Zheng, Dan; Bao, Jianguo; Lu, Jueming; Gao, Chunlei

2015-02-01

Furfural was found to be the main organic pollutant in the wastewater coming from the Diosgenin factory. This substance is derived from acidic pentosan in Dioscorea zingiberensis and is also found in a variety of agricultural byproducts, including corncobs, oat, wheat bran, and sawdust. It is regarded as a toxicant and an inhibitor to the growth of microorganism in both sewage disposal and biological fermentation. A furfural-degrading strain (DS1) was isolated from activated sludge of wastewater treatment plant in a diosgenin factory by continuous enrichment culture. The strain was identified as Bacillus cereus based on morphological, physiological tests, as well as on 16S rDNA sequence and Biolog analyses. The capacity of this strain to grow on a mineral salt medium, utilizing furfural as the sole carbon and energy source to degrade furfural, was investigated in this study. Under the condition of pH 9.0, temperature 35 °C, with rotating speed of 150 rpm, and an inoculum of 6 %, the strain showed that the furfural degradation capacity reaches 35 % in 7 days, as measured by high-performance liquid chromatography. The addition of inorganic carbon sources could bring down the biodegradation efficiency of the furfural. The strain DS1 showed better furfural removal capacity, as compared to other inorganic carbon sources in the media. Furthermore, a furfural concentration of as high as 4,000 mg L(-1) was tolerated by the culture. The capacity to degrade furfural was demonstrated for the first time by using the genus B. cereus. This study suggests the possible application in biodegradation strategies.

Preliminary Evaluation of Glyceric Acid-producing Ability of Acidomonas methanolica NBRC104435 from Glycerol Containing Methanol.

Science.gov (United States)

Sato, Shun; Kitamoto, Dai; Habe, Hiroshi

2017-06-01

Some acetic acid bacteria produce large amounts of glyceric acid (GA) from glycerol in culture broth. However, methanol, which is a major contaminant of raw glycerol derived from the biodiesel fuel industry, sharply decreases cell growth and GA production [AMB Express, 3, 20, 2013]. Thus, we evaluated the methylotrophic acetic acid bacterium Acidomonas methanolica NBRC104435 for its ability to produce GA from glycerol containing methanol. This strain accumulated GA in its culture broth when 1-3 wt% glycerol was available as a carbon source. We observed improved cell growth and GA accumulation when 1 vol% methanol was added to the 3-5 wt% glycerol medium. The maximum concentration of GA was 12.8 g/L in medium containing 3 wt% glycerol plus 1 vol% methanol. In addition, the enantiomeric excess (ee) of the GA produced was revealed to be 44%, indicating that this strain converted glycerol to d-GA with a lower enantioselectivity than other acetic acid bacteria, which had 70-99% ee.

Newcastle disease B1 vaccine strain in wild rock pigeons in Atlanta, Georgia

Science.gov (United States)

From June to October of 2012, samples were collected from wild Rock Pigeons (Columba livia) in urban neighborhoods of Atlanta, Georgia to ascertain the prevalence of pigeon paramyxovirus serotype-1 (PPMV-1). PPMV-1 strains are a subset of avian paramyxovirus serotype-1 (APMV-1) commonly isolated fro...

vacA s1m1 genotype and cagA EPIYA-ABC pattern are predominant among Helicobacter pylori strains isolated from Mexican patients with chronic gastritis.

Science.gov (United States)

Atrisco-Morales, Josefina; Martínez-Santos, Verónica I; Román-Román, Adolfo; Alarcón-Millán, Judit; De Sampedro-Reyes, José; Cruz-Del Carmen, Iván; Martínez-Carrillo, Dinorah N; Fernández-Tilapa, Gloria

2018-03-01

Virulent genotypes of Helicobacter pylori vacA s1m1/cagA + /babA2 + have been associated with severe gastric diseases. VacA, CagA and BabA are polymorphic proteins, and their association with the disease is allele-dependent. The aims of this work were: (i) to determine the prevalence of H. pylori by type of chronic gastritis; (ii) to describe the frequency of cagA, babA2 and vacA genotypes in strains from patients with different types of chronic gastritis; (iii) to characterize the variable region of cagA alleles. A total of 164 patients with chronic gastritis were studied. Altogether, 50 H. pylori strains were isolated, and the status of cagA, babA2 and vacA genotypes was examined by PCR. cagA EPIYA segment identification was performed using PCR and sequencing of cagA fragments of six randomly selected strains.Results/Key findings. The overall prevalence of H. pylori was 30.5 %. Eighty percent of the isolated strains were vacA s1m1, and the cagA and babA2 genes were detected in 74 and 32 % of the strains, respectively. The most frequent genotypes were vacA s1m1/cagA + /babA2 - and vacA s1m1/cagA + /babA2 + , with 40 % (20/50) and 28 % (14/50), respectively. In cagA + , the most frequent EPIYA motif was -ABC (78.4 %), and EPIYA-ABCC and -ABCCC motifs were found in 10.8 % of the strains. A modified EPIYT-B motif was found in 66.6 % of the sequenced strains. H. pylori strains carrying vacA s1m1, cagA + and babA2 - genotypes were the most prevalent in patients with chronic gastritis from the south of Mexico. In the cagA + strains, the EPIYA-ABC motif was the most common.

Production of carbon-13-labeled cadaverine by engineered Corynebacterium glutamicum using carbon-13-labeled methanol as co-substrate.

Science.gov (United States)

Leßmeier, Lennart; Pfeifenschneider, Johannes; Carnicer, Marc; Heux, Stephanie; Portais, Jean-Charles; Wendisch, Volker F

2015-12-01

Methanol, a one-carbon compound, can be utilized by a variety of bacteria and other organisms as carbon and energy source and is regarded as a promising substrate for biotechnological production. In this study, a strain of non-methylotrophic Corynebacterium glutamicum, which was able to produce the polyamide building block cadaverine as non-native product, was engineered for co-utilization of methanol. Expression of the gene encoding NAD+-dependent methanol dehydrogenase (Mdh) from the natural methylotroph Bacillus methanolicus increased methanol oxidation. Deletion of the endogenous aldehyde dehydrogenase genes ald and fadH prevented methanol oxidation to carbon dioxide and formaldehyde detoxification via the linear formaldehyde dissimilation pathway. Heterologous expression of genes for the key enzymes hexulose-6-phosphate synthase and 6-phospho-3-hexuloisomerase of the ribulose monophosphate (RuMP) pathway in this strain restored growth in the presence of methanol or formaldehyde, which suggested efficient formaldehyde detoxification involving RuMP key enzymes. While growth with methanol as sole carbon source was not observed, the fate of 13C-methanol added as co-substrate to sugars was followed and the isotopologue distribution indicated incorporation into central metabolites and in vivo activity of the RuMP pathway. In addition, 13C-label from methanol was traced to the secreted product cadaverine. Thus, this synthetic biology approach led to a C. glutamicum strain that converted the non-natural carbon substrate methanol at least partially to the non-native product cadaverine.

Isolation of endosulfan sulfate-degrading Rhodococcus koreensis strain S1-1 from endosulfan contaminated soil and identification of a novel metabolite, endosulfan diol monosulfate

International Nuclear Information System (INIS)

Ito, Koji; Kawashima, Fujimasa; Takagi, Kazuhiro; Kataoka, Ryota; Kotake, Masaaki; Kiyota, Hiromasa; Yamazaki, Kenichi; Sakakibara, Futa; Okada, Sanae

2016-01-01

An aerobic endosulfan sulfate-degrading bacterium, Rhodococcus koreensis strain S1-1, was isolated from soil to which endosulfan had been applied annually for more than 10 years until 2008. The strain isolated in this work reduced the concentration of endosulfan sulfate (2) from 12.25 μM to 2.11 μM during 14 d at 30 °C. Using ultra performance liquid chromatography-electrospray ionization-mass spectroscopy (UPLC-ESI-MS), a new highly water-soluble metabolite possessing six chlorine atoms was found to be endosulfan diol monosulfate (6), derived from 2 by hydrolysis of the cyclic sulfate ester ring. The structure of 6 was elucidated by chemical synthesis of the candidate derivatives and by HR-MS and UPLC-MS analyses. Therefore, it was suggested that the strain S1-1 has a new metabolic pathway of 2. In addition, 6 was expected to be less toxic among the metabolites of 1 because of its higher water-solubility. -- Highlights: •A novel endosulfan sulfate-degrading bacterium was isolated and named strain S1-1. •Strain S1-1 degraded endosulfan sulfate into a novel metabolite endosulfan diol monosulfate. •Endosulfan diol monosulfate showed higher polarity than other known metabolites of endosulfan. •We proposed the plausible metabolic pathway of endosulfan in terms of organic chemistry.

Isolation of endosulfan sulfate-degrading Rhodococcus koreensis strain S1-1 from endosulfan contaminated soil and identification of a novel metabolite, endosulfan diol monosulfate

Energy Technology Data Exchange (ETDEWEB)

Ito, Koji; Kawashima, Fujimasa [Department of Applied Biology and Chemistry, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo, 156-8502 (Japan); Organochemicals Division, National Institute for Agro-Environmental Sciences, 3-1-3 Kannondai, Tsukuba, Ibaraki, 305-8604 (Japan); Takagi, Kazuhiro, E-mail: ktakagi@affrc.go.jp [Department of Applied Biology and Chemistry, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo, 156-8502 (Japan); Organochemicals Division, National Institute for Agro-Environmental Sciences, 3-1-3 Kannondai, Tsukuba, Ibaraki, 305-8604 (Japan); Kataoka, Ryota [Department of Environmental Science, University of Yamanashi, 41-4-37 Takeda, Kofu, Yamanashi (Japan); Kotake, Masaaki [Graduate School of Agricultural Science, Tohoku University, Aoba-ku, Sendai 981-8555 (Japan); Kiyota, Hiromasa [Graduate School of Environmental & Life Science, Okayama University, 1-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530 (Japan); Yamazaki, Kenichi [Organochemicals Division, National Institute for Agro-Environmental Sciences, 3-1-3 Kannondai, Tsukuba, Ibaraki, 305-8604 (Japan); Sakakibara, Futa [Organochemicals Division, National Institute for Agro-Environmental Sciences, 3-1-3 Kannondai, Tsukuba, Ibaraki, 305-8604 (Japan); The Japan Society for the Promotion of Science(JSPS), 1-8 Chiyoda-ku, Tokyo (Japan); Okada, Sanae [Department of Applied Biology and Chemistry, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo, 156-8502 (Japan)

2016-05-13

An aerobic endosulfan sulfate-degrading bacterium, Rhodococcus koreensis strain S1-1, was isolated from soil to which endosulfan had been applied annually for more than 10 years until 2008. The strain isolated in this work reduced the concentration of endosulfan sulfate (2) from 12.25 μM to 2.11 μM during 14 d at 30 °C. Using ultra performance liquid chromatography-electrospray ionization-mass spectroscopy (UPLC-ESI-MS), a new highly water-soluble metabolite possessing six chlorine atoms was found to be endosulfan diol monosulfate (6), derived from 2 by hydrolysis of the cyclic sulfate ester ring. The structure of 6 was elucidated by chemical synthesis of the candidate derivatives and by HR-MS and UPLC-MS analyses. Therefore, it was suggested that the strain S1-1 has a new metabolic pathway of 2. In addition, 6 was expected to be less toxic among the metabolites of 1 because of its higher water-solubility. -- Highlights: •A novel endosulfan sulfate-degrading bacterium was isolated and named strain S1-1. •Strain S1-1 degraded endosulfan sulfate into a novel metabolite endosulfan diol monosulfate. •Endosulfan diol monosulfate showed higher polarity than other known metabolites of endosulfan. •We proposed the plausible metabolic pathway of endosulfan in terms of organic chemistry.

Effect of nutrition, vitamin, grains, and temperature on the mycelium growth and antioxidant capacity of Cordyceps militaris (strains AG-1 and PSJ-1

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Hung-Ngoc Dang

2018-04-01

Full Text Available Effects of subculture conditions on the mycelium growth and antioxidant capacity assessment of Cordyceps militaris trains AG-1 and PSJ-1 were carried out in laboratory during the autumn-winter season of 2015. Different temperature regimes and nutrition, vitamins levels, grain in substrate were evaluated for optimization on mycelium growth. The results showed that two strains AG-1 and PSJ-1 can grow the maximum mycelium radial at the temperature of 24 °C. The mycelium growth was improved by carbon sources such as glucose, dextrose, fructose, and maltose at 30 g/L concentration. Whereas glucose achieved the highest value of mycelium colony diameter in strains AG-1 and PSJ-1. Vitamins B1 concentrations at 0.03 g/L also gave the great values in mycelium colony diameter of both strains AG-1 and PSJ-1. The studies depicted that a substrate mixed with various grains sources (brown rice, white rice, and wheat, black glutinous rice Vietnam, and corn cultured at 24 °C, for 12 days supported maximum mycelia growth of the two strains AG-1 and PSJ-1 of C. militaris. The effect of liquid culture medium (MYPS and PD with mycelium on the anti-oxidation capacity was assessed. The results showed that the increasing of DPPH radical scavenging capacity with the extract concentration exist a proportional relation and Fe2+-chelating capacity as well. The cultured Cordyceps mycelium of two strains AG-1 and PSJ-1had the equally strong antioxidant capacity. Keywords: Cordyceps militaris, Mycelium growth, Nutritional condition, Temperature, Vitamins, Anti-oxidation activity

Isolation and characterization of a biosurfactant producing strain, Brevibacilis brevis HOB1.

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Haddad, Namir I A; Wang, Ji; Mu, Bozhong

2008-12-01

Biosurfactant-producing bacteria were isolated from the production water of an oil field. Isolates were screened for biosurfactant production using surface tension test. The highest reduction of surface tension was achieved with a bacterial strain which was identified by 16S rRNA gene sequencing as Brevibacilis brevis HOB1. It has been investigated using different carbon and nitrogen sources. It showed that the strain was able to grow and reduce the surface tension of the broth to 29 mN/m on commercial sugar and maltose, and to 32 mN/m on glucose after 72 h of growth. The maximum amount of biosurfactant was obtained when nitrate ions were supplied as nitrogen source. Biosurfactant produced by Brevibacilis brevis HOB1 was confirmed as a lipopeptide class of biosurfactant using TLC test and mass spectra. Lipopeptide isoforms were isolated from cell-free supernatants by acid-precipitation followed by one step of chromatographic separation on solid-phase ODS C18 column. The separation was confirmed by HPLC and ESI Q-TOF MS spectroscopy. Comparing the mass data obtained and the mass numbers reported for the lipopeptide complexes from other strains, it can be concluded that the major lipopeptide product of Brevibacilis brevis HOB1 is the surfactin isoform. This lipopeptide showed strong antibacterial and antifungal activity. It is a candidate for the biocontrol of pathogens in agriculture and other industries.

Genome Sequences of Two Pseudomonas syringae pv. tomato Race 1 Strains, Isolated from Tomato Fields in California

OpenAIRE

Thapa, Shree P.; Coaker, Gitta

2016-01-01

Pseudomonas syringae pv. tomato race 1 strains have evolved to overcome genetic resistance in tomato. Here, we present the draft genome sequences of two race 1 P.?syringae pv. tomato strains, A9 and 407, isolated from diseased tomato plants in California.

New Topical Treatment Options for Actinic Keratosis: A Systematic Review.

Science.gov (United States)

Stockfleth, Eggert; Sibbring, Gillian C; Alarcon, Ivette

2016-01-01

This systematic review compared the relative efficacy of 5-fluorouracil 0.5% in salicylic acid 10% (5-FU/SA), ingenol mebutate (IMB) and imiquimod 2.5%/3.75% (IMI) for actinic keratosis on the face, forehead or scalp. Only 11 publications, relating to 7 randomised controlled trials, met inclusion criteria and it was only possible to compare the effect of all 3 treatments on complete clinical clearance, and the effect of 5-FU/SA and IMB on actinic keratosis recurrence rate. Despite a higher vehicle response rate for 5-FU/SA, complete clinical clearance was higher than IMB and IMI (55.4, 42.2, and 25.0-30.6/34.0-35.6%, [corrected] respectively). 5-FU/SA was also associated with lower actinic keratosis recurrence rate than IMB at 12 months post-treatment (32.7 vs. 53.9%). Although qualitative assessment suggested a numerical advantage of 5-FU/SA over IMB and IMI in terms of complete clinical clearance and sustained clearance, clinical data from longer term trials, with comparable outcome measures, are required to corroborate these findings.

Genomic characterization of a large outbreak of Legionella pneumophila serogroup 1 strains in Quebec City, 2012.

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Simon Lévesque

Full Text Available During the summer of 2012, a major Legionella pneumophila serogroup 1 outbreak occurred in Quebec City, Canada, which caused 182 declared cases of Legionnaire's disease and included 13 fatalities. Legionella pneumophila serogroup 1 isolates from 23 patients as well as from 32 cooling towers located in the vicinity of the outbreak were recovered for analysis. In addition, 6 isolates from the 1996 Quebec City outbreak and 4 isolates from patients unrelated to both outbreaks were added to allow comparison. We characterized the isolates using pulsed-field gel electrophoresis, sequence-based typing, and whole genome sequencing. The comparison of patients-isolated strains to cooling tower isolates allowed the identification of the tower that was the source of the outbreak. Legionella pneumophila strain Quebec 2012 was identified as a ST-62 by sequence-based typing methodology. Two new Legionellaceae plasmids were found only in the epidemic strain. The LVH type IV secretion system was found in the 2012 outbreak isolates but not in the ones from the 1996 outbreak and only in half of the contemporary human isolates. The epidemic strains replicated more efficiently and were more cytotoxic to human macrophages than the environmental strains tested. At least four Icm/Dot effectors in the epidemic strains were absent in the environmental strains suggesting that some effectors could impact the intracellular replication in human macrophages. Sequence-based typing and pulsed-field gel electrophoresis combined with whole genome sequencing allowed the identification and the analysis of the causative strain including its likely environmental source.

Complete genome sequence of 'Thermobaculum terrenum' type strain (YNP1).

Science.gov (United States)

Kiss, Hajnalka; Cleland, David; Lapidus, Alla; Lucas, Susan; Del Rio, Tijana Glavina; Nolan, Matt; Tice, Hope; Han, Cliff; Goodwin, Lynne; Pitluck, Sam; Liolios, Konstantinos; Ivanova, Natalia; Mavromatis, Konstantinos; Ovchinnikova, Galina; Pati, Amrita; Chen, Amy; Palaniappan, Krishna; Land, Miriam; Hauser, Loren; Chang, Yun-Juan; Jeffries, Cynthia D; Lu, Megan; Brettin, Thomas; Detter, John C; Göker, Markus; Tindall, Brian J; Beck, Brian; McDermott, Timothy R; Woyke, Tanja; Bristow, James; Eisen, Jonathan A; Markowitz, Victor; Hugenholtz, Philip; Kyrpides, Nikos C; Klenk, Hans-Peter; Cheng, Jan-Fang

2010-10-27

'Thermobaculum terrenum' Botero et al. 2004 is the sole species within the proposed genus 'Thermobaculum'. Strain YNP1(T) is the only cultivated member of an acid tolerant, extremely thermophilic species belonging to a phylogenetically isolated environmental clone group within the phylum Chloroflexi. At present, the name 'Thermobaculum terrenum' is not yet validly published as it contravenes Rule 30 (3a) of the Bacteriological Code. The bacterium was isolated from a slightly acidic extreme thermal soil in Yellowstone National Park, Wyoming (USA). Depending on its final taxonomic allocation, this is likely to be the third completed genome sequence of a member of the class Thermomicrobia and the seventh type strain genome from the phylum Chloroflexi. The 3,101,581 bp long genome with its 2,872 protein-coding and 58 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project.

MUTANT STRAIN of Bacillus subtilis IFBG MC-1 WITH INCREASED TRYPTOPHAN SYNTHESIS

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A. F. Tkachenko

2013-12-01

Full Text Available Scientific research of essential amino acids biotechnology is directed both to create optimum conditions for producer’s cultivation and economically viable raw materials selection for these technologies, so as breeding the more productive microorganisms strains capable of extracellular producing amino acids. For successful microbial synthesis it is necessary to have an excellent crop’s metabolism knowledge and ensure that the composition of growth medium have no repressing substances. Bacterial cultures from «Collection microorganism’s stains and plants line for food and agriculture biotechnology» from Institute of Food Biotechnology and Genomics of National Academy of Sciences of Ukraine have been studied. Tryptophan producer Bacillus subtilis have been selected, which accumulated the greatest amount of this amino acid in the cultivation liquid. The optimal culture producer conditions were selected. Using selection methods, namely mutagenesis with UV irradiation and sequential stepwise selection, mutant strain Bacillus subtilis IFBG MC-1 were obtained which produced nearly 50% more tryptophan (13.9 g/l than the parent strain.

Aeromonas caviae strain induces Th1 cytokine response in mouse intestinal tract

Energy Technology Data Exchange (ETDEWEB)

Hayes, S L; Lye, D J; McKinstry, Craig A.; Vesper, Sephen J.

2010-01-01

Aeromonas caviae has been associated with human gastrointestinal disease. Strains of this species typically lack virulence factors (VFs) such as enterotoxins and hemolysins that are produced by other human pathogens of the Aeromonas genus. Microarray profiling of murine small intestinal extracts, 24 hours after oral infection with an A. caviae strain, provides evidence of a Th1 type immune response. A large number of gamma-interferon (γ-IFN) induced genes are up-regulated as well as several tumor necrosis factor-alpha (TNF-α) transcripts. A. caviae has always been considered as opportunistic pathogen because it lacks obvious virulence factors. This current effort suggests that an A. caviae strain can colonize the murine intestinal tract and cause what has been described by others as a dysregulatory cytokine response. This response could explain why a number of diarrheal waterborne disease cases have been attributed to A. caviae even though it lacks obvious enteropathogenic properties.

Vitamin K epoxide reductase complex subunit 1 (Vkorc1 haplotype diversity in mouse priority strains

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Kohn Michael H

2008-12-01

Full Text Available Abstract Background Polymorphisms in the vitamin K-epoxide reductase complex subunit 1 gene, Vkorc1, could affect blood coagulation and other vitamin K-dependent proteins, such as osteocalcin (bone Gla protein, BGP. Here we sequenced the Vkorc1 gene in 40 mouse priority strains. We analyzed Vkorc1 haplotypes with respect to prothrombin time (PT and bone mineral density and composition (BMD and BMC; phenotypes expected to be vitamin K-dependent and represented by data in the Mouse Phenome Database (MPD. Findings In the commonly used laboratory strains of Mus musculus domesticus we identified only four haplotypes differing in the intron or 5' region sequence of the Vkorc1. Six haplotypes differing by coding and non-coding polymorphisms were identified in the other subspecies of Mus. We detected no significant association of Vkorc1 haplotypes with PT, BMD and BMC within each subspecies of Mus. Vkorc1 haplotype sequences divergence between subspecies was associated with PT, BMD and BMC. Conclusion Phenotypic variation in PT, BMD and BMC within subspecies of Mus, while substantial, appears to be dominated by genetic variation in genes other than the Vkorc1. This was particularly evident for M. m. domesticus, where a single haplotype was observed in conjunction with virtually the entire range of PT, BMD and BMC values of all 5 subspecies of Mus included in this study. Differences in these phenotypes between subspecies also should not be attributed to Vkorc1 variants, but should be viewed as a result of genome wide genetic divergence.

Strain-dependent magnetism and electrical conductivity of La1-xSrxCoO3

International Nuclear Information System (INIS)

Zeneli, Orkidia

2011-01-01

In this work, the effects of epitaxial strain and film thickness on the lattice structure, microstructure, magnetization and electrical conduction of La 1-x Sr x CoO 3 (LSCO) (x=0.18 and 0.30) thin films have been studied using thickness-dependent film series on several types of single-crystalline substrates. Alternatively, the direct effect of strain has been probed using a piezoelectric substrate. La 0.7 Sr 0.3 CoO 3 is a ferromagnetic metal, whereas La 0.82 Sr 0.18 CoO 3 is at the phase boundary between the ferromagnetic metal and an insulating spin glass phase. Epitaxial biaxial strain in La 1-x Sr x CoO 3 (x=0.18-0.3) films is known to reduce the ferromagnetic double exchange interactions. It has further been suggested for the control of the crystal field splitting of the Co ions which may be utilized to manipulate the spin state. The LSCO (x = 0.18 and 0.30) films have been grown by pulsed laser deposition (PLD) on substrates of LaAlO 3 , SrTiO 3 , (PbMg 1/3 Nb 2/3 O 3 ) 0.72 (PbTiO 3 ) 0.28 (PMN-PT) and (LaAlO 3 ) 0.3 (Sr 2 TaAlO 6 ) 0.7 (LSAT), which provide different strain states and, in the case of PMN-PT, a reversibly controllable strain. Thickness-dependent series of La 0.82 Sr 0.18 CoO 3 on SrTiO 3 and LaAlO 3 as well as of La 0.7 Sr 0.3 CoO 3 on LSAT have been studied. The lattice parameters of the epitaxially grown films were determined from X-ray diffraction measurements (Bragg-Brentano method and reciprocal space mapping). Large tensile strains of 2% can be achieved in thicker films of up to 100 nm. On the other hand, the films under larger tensile strain have cracks and reveal ordered superstructures in HRTEM images which are tentatively attributed to ordered oxygen vacancies. The Curie temperature and the magnetic moment of the x=0.18 films increases towards larger film thickness in qualitative agreement with the joined effects of strain relaxation and finite thickness on magnetic ordering. In order to separate the direct strain effect from the

Culture supernatants from V. cholerae O1 El Tor strains isolated from different geographic areas induce cell vacuolation and cytotoxicity.

Science.gov (United States)

Vidal, Jorge E; Enríquez-Rincón, Fernando; Giono-Cerezo, Silvia; Ribas-Aparicio, Rosa María; Figueroa-Arredondo, Paula

2009-01-01

To investigate whether the HlyA-induced vacuolating effect is produced by V. cholerae O1 ElTor strains isolated from different geographic origins, including Mexico. Supernatant-induced haemolysis, vacuolating activity and cytotoxicity in Vero cells were recorded. PCR, RFLP analysis and molecular cloning were performed. All ElTor strains analyzed induced cellular vacuolation. Ribotype 2 strains isolates from the U.S. gulf coast yielded the highest titer of vacuolating activity. Eight of nine strains were haemolytic, while all strains were PCR positive for the hlyA gene. We cloned the hlyA gene from two ElTor strains, a toxigenic (2514-88, ctxAB+) and a non-toxigenic Mexican strain (CM 91-3, ctxAB-). Supernatant from those recombinant E. coli strains induced haemolysis, cell vacuolation and cytotoxicity. RFLP-PCR analysis revealed similarities in the hlyA gene from all strains tested. The HlyA-induced vacuolating effect is a widespread phenotype of epidemic V. cholerae O1 ElTor strains.

Genomic differentiation among two strains of the PS1 clade isolated from geographically separated marine habitats

KAUST Repository

Jimenez Infante, Francy M.; Ngugi, David; Alam, Intikhab; Rashid, Mamoon; Ba Alawi, Wail; Kamau, Allan; Bajic, Vladimir B.; Stingl, Ulrich

2014-01-01

Using dilution-to-extinction cultivation, we isolated a strain affiliated with the PS1 clade from surface waters of the Red Sea. Strain RS24 represents the second isolate of this group of marine Alphaproteobacteria after IMCC14465 that was isolated

Effect of Aspergillus versicolor strain JASS1 on low density polyethylene degradation

Science.gov (United States)

Gajendiran, A.; Subramani, S.; Abraham, J.

2017-11-01

Low density polyethylene (LDPE) waste disposal remains one of the major environmental concerns faced by the world today. In past decades, major focus has been given to enhance the biodegradation of LDPE by microbial species. In this present study, Aspergillus versicolor with the ability to degrade LDPE was isolated from municipal landfill area using enrichment technique. Based on 18S rRNA gene sequencing confirmed its identity as Aspergillus versicolor. The biodegradation study was carried out for 90 d in M1 medium. The degradation behaviour of LDPE films by Aspergillus versicolor strain JASS1 were confirmed by weight loss, CO2 evolution, Scanning electron microscopy (SEM) analysis, Atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR) technique. From current investigation, it can be concluded that our isolated strain JASS1 had the potential to degrade LDPE films and it can be useful in solving the problem caused by polyethylene in the environment.

Assessing the in vitro fitness of an oseltamivir-resistant seasonal A/H1N1 influenza strain using a mathematical model.

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Benjamin P Holder

2011-03-01

Full Text Available In 2007, the A/Brisbane/59/2007 (H1N1 seasonal influenza virus strain acquired the oseltamivir-resistance mutation H275Y in its neuraminidase (NA gene. Although previous studies had demonstrated that this mutation impaired the replication capacity of the influenza virus in vitro and in vivo, the A/Brisbane/59/2007 H275Y oseltamivir-resistant mutant completely out-competed the wild-type (WT strain and was, in the 2008-2009 influenza season, the primary A/H1N1 circulating strain. Using a combination of plaque and viral yield assays, and a simple mathematical model, approximate values were extracted for two basic viral kinetics parameters of the in vitro infection. In the ST6GalI-MDCK cell line, the latent infection period (i.e., the time for a newly infected cell to start releasing virions was found to be 1-3 h for the WT strain and more than 7 h for the H275Y mutant. The infecting time (i.e., the time for a single infectious cell to cause the infection of another one was between 30 and 80 min for the WT, and less than 5 min for the H275Y mutant. Single-cycle viral yield experiments have provided qualitative confirmation of these findings. These results, though preliminary, suggest that the increased fitness success of the A/Brisbane/59/2007 H275Y mutant may be due to increased infectivity compensating for an impaired or delayed viral release, and are consistent with recent evidence for the mechanistic origins of fitness reduction and recovery in NA expression. The method applied here can reconcile seemingly contradictory results from the plaque and yield assays as two complementary views of replication kinetics, with both required to fully capture a strain's fitness.

Exploring effects of self-management on glycemic control using a modified information-motivation-behavioral skills model in type 2 diabetes mellitus patients in Shanghai, China: A cross-sectional study.

Science.gov (United States)

Chen, Qi; Wang, Huwen; Wang, Yichen; Wang, Zezhou; Zhao, Daijun; Cai, Yong

2018-02-19

The original information-motivation-behavioral skills (IMB) model has been verified in type 2 diabetes mellitus (T2DM) patients, but the effects of the model on glycemic control remain unclear. The aim of this study was to modify the IMB model to explore the effects of self-management on glycemic control in T2DM patients in Shanghai, China. A cross-sectional study was conducted on participants recruited using a convenience sampling method between June and August 2015 in three tertiary hospitals and four community health service centers; 796 participants meeting the inclusion criteria (age ≥18 years and a diagnosis of T2DM) completed a questionnaire and blood test for glycemic control. Structural equation models were used to test the IMB framework. The modified model demonstrated an acceptable fit of the data. Paths from information to self-management behaviors (β = 0.119, P = 0.001) and HbA1c (β = -0.140, P motivation to behavioral skills (β = 0.670, P motivation varied with each other (r = 0.350, P Type 2 diabetes mellitus patients with poor control of glucose levels may be a better target population for application of the modified IMB model. © 2018 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and John Wiley & Sons Australia, Ltd.

Comparative Genomics and Identification of an Enterotoxin-Bearing Pathogenicity Island, SEPI-1/SECI-1, in Staphylococcus epidermidis Pathogenic Strains.

Science.gov (United States)

Argemi, Xavier; Nanoukon, Chimène; Affolabi, Dissou; Keller, Daniel; Hansmann, Yves; Riegel, Philippe; Baba-Moussa, Lamine; Prévost, Gilles

2018-02-25

Staphylococcus epidermidis is a leading cause of nosocomial infections, majorly resistant to beta-lactam antibiotics, and may transfer several mobile genetic elements among the members of its own species, as well as to Staphylococcus aureus ; however, a genetic exchange from S. aureus to S. epidermidis remains controversial. We recently identified two pathogenic clinical strains of S. epidermidis that produce a staphylococcal enterotoxin C3-like (SEC) similar to that by S. aureus pathogenicity islands. This study aimed to determine the genetic environment of the SEC-coding sequence and to identify the mobile genetic elements. Whole-genome sequencing and annotation of the S. epidermidis strains were performed using Illumina technology and a bioinformatics pipeline for assembly, which provided evidence that the SEC-coding sequences were located in a composite pathogenicity island that was previously described in the S. epidermidis strain FRI909, called SePI-1/SeCI-1, with 83.8-89.7% nucleotide similarity. Various other plasmids were identified, particularly p_3_95 and p_4_95, which carry antibiotic resistance genes ( hsrA and dfrG , respectively), and share homologies with SAP085A and pUSA04-2-SUR11, two plasmids described in S. aureus . Eventually, one complete prophage was identified, ΦSE90, sharing 30 out of 52 coding sequences with the Acinetobacter phage vB_AbaM_IME200. Thus, the SePI-1/SeCI-1 pathogenicity island was identified in two pathogenic strains of S. epidermidis that produced a SEC enterotoxin causing septic shock. These findings suggest the existence of in vivo genetic exchange from S. aureus to S. epidermidis .

Comparative Genomics and Identification of an Enterotoxin-Bearing Pathogenicity Island, SEPI-1/SECI-1, in Staphylococcus epidermidis Pathogenic Strains

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Xavier Argemi

2018-02-01

Full Text Available Staphylococcus epidermidis is a leading cause of nosocomial infections, majorly resistant to beta-lactam antibiotics, and may transfer several mobile genetic elements among the members of its own species, as well as to Staphylococcus aureus; however, a genetic exchange from S. aureus to S. epidermidis remains controversial. We recently identified two pathogenic clinical strains of S. epidermidis that produce a staphylococcal enterotoxin C3-like (SEC similar to that by S. aureus pathogenicity islands. This study aimed to determine the genetic environment of the SEC-coding sequence and to identify the mobile genetic elements. Whole-genome sequencing and annotation of the S. epidermidis strains were performed using Illumina technology and a bioinformatics pipeline for assembly, which provided evidence that the SEC-coding sequences were located in a composite pathogenicity island that was previously described in the S. epidermidis strain FRI909, called SePI-1/SeCI-1, with 83.8–89.7% nucleotide similarity. Various other plasmids were identified, particularly p_3_95 and p_4_95, which carry antibiotic resistance genes (hsrA and dfrG, respectively, and share homologies with SAP085A and pUSA04-2-SUR11, two plasmids described in S. aureus. Eventually, one complete prophage was identified, ΦSE90, sharing 30 out of 52 coding sequences with the Acinetobacter phage vB_AbaM_IME200. Thus, the SePI-1/SeCI-1 pathogenicity island was identified in two pathogenic strains of S. epidermidis that produced a SEC enterotoxin causing septic shock. These findings suggest the existence of in vivo genetic exchange from S. aureus to S. epidermidis.

Emergence of a virulent porcine reproductive and respiratory syndrome virus (PRRSV 1 strain in Lower Austria

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Leonie J Sinn

2016-11-01

Full Text Available Abstract Background In spring 2015, an outbreak of porcine reproductive and respiratory syndrome (PRRS struck Lower Austria caused by a PRRS virus (PRRSV strain spreading rapidly among both previously PRRSV negative and vaccinated pig herds. This case report describes the first well-documented emergence of the PRRSV strain responsible for this outbreak. Case presentation A PRRSV seronegative piglet-producing farm in Lower Austria encountered losses in foetuses and suckling piglets of up to 90 %; clinical signs in sows and nursery piglets included fever and reduced feed intake. Additionally, high percentages of repeat breeders and losses of up to 40 % in nursery piglets occurred. An infection with PRRSV was suggested by the detection of antibodies by enzyme linked immunosorbent assay and confirmed by quantitative real time PCR. The underlying PRRSV strain, termed AUT15-33, was isolated by passage on porcine alveolar macrophages, partially sequenced (ORF2-7 and grouped as PRRSV-1, subtype 1. In phylogenetic analysis of the genome region coding for the structural proteins, ORF2-7, AUT15-33 clustered with Belgian strains but identities were as low as 88 %. In contrast, analysis of ORF7 sequences revealed a close relationship to Croatian strains from 2012 with an identity of 94 – 95 %. Conclusions In the year following the outbreak, the same PRRSV strain was identified repeatedly in different regions of Austria. It can be speculated that the new strain has novel advantageous properties.

Distribution and content of class 1 integrons in different Vibrio cholerae O-serotype strains isolated in Thailand

DEFF Research Database (Denmark)

Dalsgaard, Anders; Forslund, Anita; Serichantalergs, Oralak

2000-01-01

only a single antibiotic resistance gene. Although resistance genes in class 1 integrons were found in strains from the same epidemic, as well as in unrelated non-O1, non-O139 strains isolated from children with diarrhea, they were found to encode only some of the antibiotic resistance expressed...

Strain Tuning of the Charge Density Wave in Monolayer and Bilayer 1T-TaS2

KAUST Repository

Gan, Liyong; Zhang, Lihong; Zhang, Qingyun; Guo, Chunsheng; Schwingenschlö gl, Udo; Zhao, Yong

2015-01-01

By first-principles calculations, we investigate the strain effects on the charge density wave states of monolayer and bilayer 1T-TaS2. The modified stability of the charge density wave in the monolayer is understood in terms of the strain dependent

R5 strains of human immunodeficiency virus type 1 from rapid progressors lacking X4 strains do not possess X4-type pathogenicity in human thymus

NARCIS (Netherlands)

Berkowitz, R. D.; van't Wout, A. B.; Kootstra, N. A.; Moreno, M. E.; Linquist-Stepps, V. D.; Bare, C.; Stoddart, C. A.; Schuitemaker, H.; McCune, J. M.

1999-01-01

Some individuals infected with only R5 strains of human immunodeficiency virus type 1 progress to AIDS as quickly as individuals harboring X4 strains. We determined that three R5 viruses were much less pathogenic than an X4 virus in SCID-hu Thy/Liv mice, suggesting that R5 virus-mediated rapid

Enhanced Electron Mobility in Nonplanar Tensile Strained Si Epitaxially Grown on SixGe1-x Nanowires.

Science.gov (United States)

Wen, Feng; Tutuc, Emanuel

2018-01-10

We report the growth and characterization of epitaxial, coherently strained Si x Ge 1-x -Si core-shell nanowire heterostructure through vapor-liquid-solid growth mechanism for the Si x Ge 1-x core, followed by an in situ ultrahigh-vacuum chemical vapor deposition for the Si shell. Raman spectra acquired from individual nanowire reveal the Si-Si, Si-Ge, and Ge-Ge modes of the Si x Ge 1-x core and the Si-Si mode of the shell. Because of the compressive (tensile) strain induced by lattice mismatch, the core (shell) Raman modes are blue (red) shifted compared to those of unstrained bare Si x Ge 1-x (Si) nanowires, in good agreement with values calculated using continuum elasticity model coupled with lattice dynamic theory. A large tensile strain of up to 2.3% is achieved in the Si shell, which is expected to provide quantum confinement for electrons due to a positive core-to-shell conduction band offset. We demonstrate n-type metal-oxide-semiconductor field-effect transistors using Si x Ge 1-x -Si core-shell nanowires as channel and observe a 40% enhancement of the average electron mobility compared to control devices using Si nanowires due to an increased electron mobility in the tensile-strained Si shell.

Measurement of Strain and Strain Rate during the Impact of Tennis Ball Cores

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Ben Lane

2018-03-01

Full Text Available The aim of this investigation was to establish the strains and strain rates experienced by tennis ball cores during impact to inform material characterisation testing and finite element modelling. Three-dimensional surface strains and strain rates were measured using two high-speed video cameras and corresponding digital image correlation software (GOM Correlate Professional. The results suggest that material characterisation testing to a maximum strain of 0.4 and a maximum rate of 500 s−1 in tension and to a maximum strain of −0.4 and a maximum rate of −800 s−1 in compression would encapsulate the demands placed on the material during impact and, in turn, define the range of properties required to encapsulate the behavior of the material during impact, enabling testing to be application-specific and strain-rate-dependent properties to be established and incorporated in finite element models.

Identification of Brucella melitensis Rev.1 vaccine-strain genetic markers: Towards understanding the molecular mechanism behind virulence attenuation.

Science.gov (United States)

Issa, Mohammad Nouh; Ashhab, Yaqoub

2016-09-22

Brucella melitensis Rev.1 is an avirulent strain that is widely used as a live vaccine to control brucellosis in small ruminants. Although an assembled draft version of Rev.1 genome has been available since 2009, this genome has not been investigated to characterize this important vaccine. In the present work, we used the draft genome of Rev.1 to perform a thorough genomic comparison and sequence analysis to identify and characterize the panel of its unique genetic markers. The draft genome of Rev.1 was compared with genome sequences of 36 different Brucella melitensis strains from the Brucella project of the Broad Institute of MIT and Harvard. The comparative analyses revealed 32 genetic alterations (30 SNPs, 1 single-bp insertion and 1 single-bp deletion) that are exclusively present in the Rev.1 genome. In silico analyses showed that 9 out of the 17 non-synonymous mutations are deleterious. Three ABC transporters are among the disrupted genes that can be linked to virulence attenuation. Out of the 32 mutations, 11 Rev.1 specific markers were selected to test their potential to discriminate Rev.1 using a bi-directional allele-specific PCR assay. Six markers were able to distinguish between Rev.1 and a set of control strains. We succeeded in identifying a panel of 32 genome-specific markers of the B. melitensis Rev.1 vaccine strain. Extensive in silico analysis showed that a considerable number of these mutations could severely affect the function of the associated genes. In addition, some of the discovered markers were able to discriminate Rev.1 strain from a group of control strains using practical PCR tests that can be applied in resource-limited settings. Copyright © 2016 Elsevier Ltd. All rights reserved.

Draft Genome Sequence of Sphingopyxis sp. Strain MWB1, a Crude-Oil-Degrading Marine Bacterium

Science.gov (United States)

Kim, Jonghyun; Kim, Soo Jung; Kim, Seon Hee; Kim, Seung Il; Moon, Yoon-Jung; Park, Sung-Joon

2014-01-01

Sphingopyxis sp. strain MWB1, which is capable of degrading crude oil, diesel, and kerosene, was isolated from crude oil–contaminated seashore in Tae-an, South Korea. Here, we report the draft genome sequence of this strain, which comprises 3,118,428 bp with a G+C content of 62.85 mol%. PMID:25477411

Monoclonal antibodies to polioviruses; comparison of intratypic strain differentiation of poliovirus type 1 using monoclonal antibodies versus cross-absorbed antisera.

NARCIS (Netherlands)

A.D.M.E. Osterhaus (Albert); A.L. van Wezel; T.G. Hazendonk; F.G.C.M. Uytdehaag (Fons); J.A.A.M. van Asten (Jack); G. van Steenis (Bert)

1983-01-01

textabstractA panel of 10 monoclonal antibodies raised to 3 different poliovirus type 1 strains was tested in a micro-enzyme-linked immunosorbent assay and in a micro-neutralization test against 87 poliovirus type 1 strains. The results, evaluated in a newly developed system for intratypic strain

Clostridium scatologenes strain SL1 isolated as an acetogenic bacterium from acidic sediments.

Science.gov (United States)

Küsel, K; Dorsch, T; Acker, G; Stackebrandt, E; Drake, H L

2000-03-01

A strictly anaerobic, H2-utilizing bacterium, strain SL1, was isolated from the sediment of an acidic coal mine pond. Cells of strain SL1 were sporulating, motile, long rods with a multilayer cell wall. Growth was observed at 5-35 degrees C and pH 3.9-7.0. Acetate was the sole end product of H2 utilization and was produced in stoichiometries indicative of an acetyl-CoA-pathway-dependent metabolism. Growth and substrate utilization also occurred with CO/CO2, vanillate, syringate, ferulate, ethanol, propanol, 1-butanol, glycerine, cellobiose, glucose, fructose, mannose, xylose, formate, lactate, pyruvate and gluconate. With most substrates, acetate was the main or sole product formed. Growth in the presence of H2/CO2 or CO/CO2 was difficult to maintain in laboratory cultures. Methoxyl, carboxyl and acrylate groups of various aromatic compounds were O-demethylated, decarboxylated and reduced, respectively. Small amounts of butyrate were produced during the fermentation of sugars. The acrylate group of ferulate was reduced. Nitrate, sulfate, thiosulfate, dimethylsulfoxide and Fe(III) were not utilized as electron acceptors. Analysis of the 16S rRNA gene sequence of strain SL1 demonstrated that it is closely related to Clostridium scatologenes (99.6% sequence similarity), an organism characterized as a fermentative anaerobe but not previously shown to be capable of acetogenic growth. Comparative experiments with C. scatologenes DSM 757T demonstrated that it utilized H2/CO2 (negligible growth), CO/CO2 (negligible growth), formate, ethanol and aromatic compounds according to stoichiometries indicative of the acetyl-CoA pathway. CO dehydrogenase, formate dehydrogenase and hydrogenase activities were present in both strain SL1 and C. scatologenes DSM 757T. These results indicate that (i) sediments of acidic coal mine ponds harbour acetogens and (ii) C. scatologenes is an acetogen that tends to lose its capacity to grow acetogenically under H2/CO2 or CO/CO2 after prolonged

Factors affecting finite strain estimation in low-grade, low-strain clastic rocks

Science.gov (United States)

Pastor-Galán, Daniel; Gutiérrez-Alonso, Gabriel; Meere, Patrick A.; Mulchrone, Kieran F.

2009-12-01

The computer strain analysis methods SAPE, MRL and DTNNM have permitted the characterization of finite strain in two different regions with contrasting geodynamic scenarios; (1) the Talas Ala Tau (Tien Shan, Kyrgyzs Republic) and (2) the Somiedo Nappe and Narcea Antiform (Cantabrian to West Asturian-Leonese Zone boundary, Variscan Belt, NW of Iberia). The performed analyses have revealed low-strain values and the regional strain trend in both studied areas. This study also investigates the relationship between lithology (grain size and percentage of matrix) and strain estimates the two methodologies used. The results show that these methods are comparable and the absence of significant finite strain lithological control in rocks deformed under low metamorphic and low-strain conditions.

Generation of uniaxial tensile strain of over 1% on a Ge substrate for short-channel strained Ge n-type Metal–Insulator–Semiconductor Field-Effect Transistors with SiGe stressors

International Nuclear Information System (INIS)

Moriyama, Yoshihiko; Kamimuta, Yuuichi; Ikeda, Keiji; Tezuka, Tsutomu

2012-01-01

Tensile strain of over 1% in Ge stripes sandwiched between a pair of SiGe source-drain stressors was demonstrated. The Metal–Oxide–Semiconductor Field-Effect Transistor (MOSFET)-like structures were fabricated on a (001)-Ge substrate having SiO 2 dummy-gate stripes with widths down to 26 nm. Recess-regions adjacent to the dummy-gate stripes were formed by an anisotropic wet etching technique. A damage-free and well-controlled anisotropic wet etching process is developed in order to avoid plasma-induced damage during a conventional Reactive-ion Etching process. The SiGe stressors were epitaxially grown on the recesses to simulate strained Ge n-channel Metal–Insulator–Semiconductor Field-Effect Transistors (MISFETs) having high electron mobility. A micro-Raman spectroscopy measurement revealed tensile strain in the narrow Ge regions which became higher for narrower regions. Tensile strain of up to 1.2% was evaluated from the measurement under an assumption of uniaxial strain configuration. These results strongly suggest that higher electron mobility than the upper limit for a Si-MOSFET is obtainable in short-channel strained Ge-nMISFETs with the embedded SiGe stressors.

Complete genome sequence of Leptospira alstonii serovar room 22, strain GWTS#1

Science.gov (United States)

We report the complete genome sequence of Leptospira alstonii serovar room 22 strain GWTS#1. This is the first isolate of L. alstonii to be cultured from a mammal, in Western Europe, and represents a new serovar of pathogenic leptospires....

Hamstring strain - aftercare

Science.gov (United States)

Pulled hamstring muscle; Sprain - hamstring ... There are 3 levels of hamstring strains: Grade 1 -- mild muscle strain or pull Grade 2 -- partial muscle tear Grade 3 -- complete muscle tear Recovery time depends ...

S1 gene sequence analysis of infectious bronchitis virus vaccinal strains (H120 & H52 and their embryo-passaged derivatives

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Bakhshesh, M.

2016-07-01

Full Text Available Avian infectious bronchitis is an acute and highly contagious disease that mainly causes respiratory symptoms in poultry. A number of serotypes and variants of the viral agent with poor cross-protection are the major problem to achieve desired immunity from vaccination. The S1 subunit of S glycoprotein (spike is the major determinant of IBV so that a minor change in amino acid sequence of this protein, alters the virus strain. Therefore, characterization of the sequence of S1 gene is necessary to identify virus strains and their similarities with the vaccinal strains. In this research, the S1 sequence of H52 and H120 vaccinal strains of Razi Institute was fully characterized, and also the effect of serial passages in embryonated - eggs (5 passages beyond the master seed on the S1 gene was investigated. The results showed that H120 and H52 strains of Razi Institute are 100% identical to the reference vaccine strains available in the GenBank. In addition, the H52 strain showed one amino acid substitution from the 3rd passage in which Glycine (G was replaced by Valine (V at position 118 making these passages exactly identical to the H120 strain while no change occurred for the H120 strain during these passages. Analysis of the original vaccinal strains which are widely administered in Iran, is definitely useful for prevention and control strategies against the circulating viruses. To identify the genetic change(s responsible for attenuation of these strains during passages in embryonated-egg, characterization of other genes, especially those involved in replication is recommended.

Analysis of Coinfections with A/H1N1 Strain Variants among Pigs in Poland by Multitemperature Single-Strand Conformational Polymorphism

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Krzysztof Lepek

2015-01-01

Full Text Available Monitoring and control of infections are key parts of surveillance systems and epidemiological risk prevention. In the case of influenza A viruses (IAVs, which show high variability, a wide range of hosts, and a potential of reassortment between different strains, it is essential to study not only people, but also animals living in the immediate surroundings. If understated, the animals might become a source of newly formed infectious strains with a pandemic potential. Special attention should be focused on pigs, because of the receptors specific for virus strains originating from different species, localized in their respiratory tract. Pigs are prone to mixed infections and may constitute a reservoir of potentially dangerous IAV strains resulting from genetic reassortment. It has been reported that a quadruple reassortant, A(H1N1pdm09, can be easily transmitted from humans to pigs and serve as a donor of genetic segments for new strains capable of infecting humans. Therefore, it is highly desirable to develop a simple, cost-effective, and rapid method for evaluation of IAV genetic variability. We describe a method based on multitemperature single-strand conformational polymorphism (MSSCP, using a fragment of the hemagglutinin (HA gene, for detection of coinfections and differentiation of genetic variants of the virus, difficult to identify by conventional diagnostic.

Characterization of Clostridium difficile Strains in British Columbia, Canada: A Shift from NAP1 Majority (2008 to Novel Strain Types (2013 in One Region

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Agatha N. Jassem

2016-01-01

Full Text Available Background. Clostridium difficile is a major cause of gastrointestinal illness. Epidemic NAP1 strains contain toxins A and B, a deletion in repressor tcdC, and a binary toxin. Objectives. To determine the molecular epidemiology of C. difficile in British Columbia and compare between two time points in one region. Methods. C. difficile isolates from hospital and community laboratories (2008 and one Island Health hospital laboratory (2013 were characterized by pulsed-field gel electrophoresis, PCR-ribotyping, toxin possession, tcdC genotype, and antimicrobial susceptibility. Results. In 2008, 42.7% of isolates had NAP1 designation. Hospital-collected isolates were associated with older patients and more NAP1 types. Unlike other isolates, most NAP1 isolates possessed binary toxin and a 19 bp loss in tcdC. All isolates were susceptible to metronidazole and vancomycin. A 2013 follow-up revealed a 28.9% decrease in NAP1 isolates and 20.0% increase in isolates without NAP designation in one region. Then, community-associated cases were seen in younger patients, while NAP types were evenly distributed. Isolates without NAP designation did not cluster with a PFGE pattern or ribotype. Conclusions. Evaluation of C. difficile infections within British Columbia revealed demographic associations, epidemiological shifts, and characteristics of strain types. Continuous surveillance of C. difficile will enable detection of emerging strains.

Phage-resistance linked to cell heterogeneity in the commercial strain Lactobacillus delbrueckii subsp. lactis Ab1.

Science.gov (United States)

Suárez, Viviana B; Maciel, Natalia; Guglielmotti, Daniela; Zago, Miriam; Giraffa, Giorgio; Reinheimer, Jorge

2008-12-10

The aim of this work was to study the relationship between the cell morphological heterogeneity and the phage-resistance in the commercial strain Lactobacillus delbrueckii subsp. lactis Ab1. Two morphological variants (named C and T) were isolated from this strain. Phage-resistant derivatives were isolated from them and the percentage of occurrence of confirmed phage-resistant cells was 0.001% of the total cellular population. Within these phage-resistant cell derivatives there were T (3 out of 4 total isolates) and C (1 out of 4 total isolates) variants. The study of some technological properties (e.g. proteolytic and acidifying activities) demonstrated that most of phage-resistant derivatives were not as good as the parental strain. However, for one derivative (a T variant), the technological properties were better than those of the parental strain. On the other hand, it was possible to determinate that the system of phage-resistance in the T variants was interference in adsorption step, with adsorption rates M.

[Morphological characteristics and physiological properties of aflatoxin B1 producing and non-producing Aspergillus flavus strains].

Science.gov (United States)

Kogbo, W; Lemarinier, S; Boutibonnes, P

1985-09-01

Comparison between about 80 strains of Aspergillus flavus, belonging to the series flavus and oryzae, obtained from international collections but also isolated from French or African substrates revealed the following observations: 1. Cultural and morphological characteristics of toxicogenic and atoxicogenic strains of A. flavus are similar. However, the former produce a diffusible yellow pigment in 83% of isolates. 2. The two groups of conidiospores have the same resistance to UV irradiation (254 nm, 5 and 10 min). All the strains are equally sensitive to 4 antifungal antibiotics: nystatine, ketoconazole, clotrimazole and amphotericine. 3. A difference was seen in the capacity to produce enzymes as alpha-galactosidase, beta-galactosidase and beta-glucosidase, implicated in the glucid metabolism. The specific hydrolytic activity has been confirmed by the characterization of a large amount of beta-galactosidase and by a diauxic growth on glucose medium supplemented by lactose. Possible relationship between these characters and aflatoxin B1 production by A. flavus strains is discussed.

Non-toxigenic environmental Vibrio cholerae O1 strain from Haiti provides evidence of pre-pandemic cholera in Hispaniola

Science.gov (United States)

Azarian, Taj; Ali, Afsar; Johnson, Judith A.; Jubair, Mohammad; Cella, Eleonora; Ciccozzi, Massimo; Nolan, David J.; Farmerie, William; Rashid, Mohammad H.; Sinha-Ray, Shrestha; Alam, Meer T.; Morris, J. Glenn; Salemi, Marco

2016-01-01

Vibrio cholerae is ubiquitous in aquatic environments, with environmental toxigenic V. cholerae O1 strains serving as a source for recurrent cholera epidemics and pandemic disease. However, a number of questions remain about long-term survival and evolution of V. cholerae strains within these aquatic environmental reservoirs. Through monitoring of the Haitian aquatic environment following the 2010 cholera epidemic, we isolated two novel non-toxigenic (ctxA/B-negative) Vibrio cholerae O1. These two isolates underwent whole-genome sequencing and were investigated through comparative genomics and Bayesian coalescent analysis. These isolates cluster in the evolutionary tree with strains responsible for clinical cholera, possessing genomic components of 6th and 7th pandemic lineages, and diverge from “modern” cholera strains around 1548 C.E. [95% HPD: 1532–1555]. Vibrio Pathogenicity Island (VPI)-1 was present; however, SXT/R391-family ICE and VPI-2 were absent. Rugose phenotype conversion and vibriophage resistance evidenced adaption for persistence in aquatic environments. The identification of V. cholerae O1 strains in the Haitian environment, which predate the first reported cholera pandemic in 1817, broadens our understanding of the history of pandemics. It also raises the possibility that these and similar environmental strains could acquire virulence genes from the 2010 Haitian epidemic clone, including the cholera toxin producing CTXϕ. PMID:27786291

Hypothalamic involvement in stress-induced hypocalcemia in rats.

Science.gov (United States)

Aou, S; Ma, J; Hori, T

1993-08-20

Although hormonal regulation of blood calcium homeostasis has been intensively investigated in the peripheral organs, the involvement of the central nervous system in calcium regulation is still poorly understood. In the present study, we found that (1) bilateral lesions of the ventromedial nucleus of the hypothalamus (VMH), but not those of the paraventricular hypothalamic nucleus or the lateral hypothalamic area, eliminated immobilization (IMB)-induced hypocalcemia, and (2) electrical stimulation of the VMH decreased the blood calcium level. The results suggest that the VMH has a hypocalcemic function and plays a role in IMB-induced hypocalcemia.

Characterization of a novel biosurfactant produced by Staphylococcus sp. strain 1E with potential application on hydrocarbon bioremediation.

Science.gov (United States)

Eddouaouda, Kamel; Mnif, Sami; Badis, Abdelmalek; Younes, Sonia Ben; Cherif, Slim; Ferhat, Samira; Mhiri, Najla; Chamkha, Mohamed; Sayadi, Sami

2012-08-01

A biosurfactant-producing bacterium (Staphylococcus sp. strain 1E) was isolated from an Algerian crude oil contaminated soil. Biosurfactant production was tested with different carbon sources using the surface tension measurement and the oil displacement test. Olive oil produced the highest reduction in surface tension (25.9 dynes cm(-1)). Crude oil presented the best substrate for 1E biosurfactant emulsification activity. The biosurfactant produced by strain 1E reduced the growth medium surface tension below 30 dynes cm(-1). This reduction was also obtained in cell-free filtrates. Biosurfactant produced by strain 1E showed stability in a wide range of pH (from 2 to 12), temperature (from 4 to 55 °C) and salinity (from 0 to 300 g l(-1)) variations. The biosurfactant produced by strain 1E belonged to lipopeptide group and also constituted an antibacterial activity againt the pathogenic bacteria such as Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Bacillus subtilis. Phenanthrene solubility in water was enhanced by biosurfactant addition. Our results suggest that the 1E biosurfactant has interesting properties for its application in bioremediation of hydrocarbons contaminated sites. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Conduction band structure and electron mobility in uniaxially strained Si via externally applied strain in nanomembranes

Energy Technology Data Exchange (ETDEWEB)

Chen Feng [Xi' an Jiaotong University, Xi' an, Shaanxi 710049 (China); Euaruksakul, Chanan; Himpsel, F J; Lagally, Max G [University of Wisconsin-Madison, Madison, WI 53706 (United States); Liu Zheng; Liu Feng, E-mail: lagally@engr.wisc.edu [University of Utah, Salt Lake City, UT 84112 (United States)

2011-08-17

Strain changes the band structure of semiconductors. We use x-ray absorption spectroscopy to study the change in the density of conduction band (CB) states when silicon is uniaxially strained along the [1 0 0] and [1 1 0] directions. High stress can be applied to silicon nanomembranes, because their thinness allows high levels of strain without fracture. Strain-induced changes in both the sixfold degenerate {Delta} valleys and the eightfold degenerate L valleys are determined quantitatively. The uniaxial deformation potentials of both {Delta} and L valleys are directly extracted using a strain tensor appropriate to the boundary conditions, i.e., confinement in the plane in the direction orthogonal to the straining direction, which correspond to those of strained CMOS in commercial applications. The experimentally determined deformation potentials match the theoretical predictions well. We predict electron mobility enhancement created by strain-induced CB modifications.

Isolating Sperm from Cell Mixtures Using Magnetic Beads Coupled with an Anti-PH-20 Antibody for Forensic DNA Analysis.

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Xing-Chun Zhao

Full Text Available Vaginal swabs taken in rape cases usually contain epithelial cells from the victim and sperm from the assailant and forensic DNA analysis requires separation of sperm from these cell mixtures. PH-20, which is a glycosylphosphatidylinositol-anchored hyaluronidase located on the head of sperm, has important functions in fertilization. Here we describe a newly developed method for sperm isolation using anti-PH-20 antibody-coupled immunomagnetic beads (anti-PH-20 IMBs. Optical microscopy and scanning electron microscopy showed the IMBs recognized the head of sperm specifically and exhibited a great capacity to capture sperm cells. However, we found it necessary to incubate the IMB-sperm complex with DNase I before sperm lysis in order to remove any female DNA completely. We compared the sensitivity of anti-PH-20 IMBs in sperm and epithelial cell discrimination to those coated with a different anti-sperm antibody (anti-SP-10, anti-ADAM2 or anti-JLP. Only the anti-PH-20 IMBs succeeded in isolating sperm from cell mixtures at a sperm/epithelial cell ratio of 103:105. Further, our method exhibited greater power and better stability for sperm isolation compared to the traditional differential lysis strategy. Taken together, the anti-PH-20 IMB method described here could be effective for the isolation of sperm needed to obtain a single-sourced DNA profile as an aid to identifying the perpetrator in sexual assault cases.

Microstructure and annealing behavior of a modified 9Cr−1Mo steel after dynamic plastic deformation to different strains

International Nuclear Information System (INIS)

Zhang, Z.B.; Mishin, O.V.; Tao, N.R.; Pantleon, W.

2015-01-01

The microstructure, hardness and tensile properties of a modified 9Cr−1Mo steel processed by dynamic plastic deformation (DPD) to different strains (0.5 and 2.3) have been investigated in the as-deformed and annealed conditions. It is found that significant structural refinement and a high level of strength can be achieved by DPD to a strain of 2.3, and that the microstructure at this strain contains a large fraction of high angle boundaries. The ductility of the DPD processed steel is however low. Considerable structural coarsening of the deformed microstructure without pronounced recrystallization takes place during annealing of the low-strain and high-strain samples for 1 h at 650 °C and 600 °C, respectively. Both coarsening and partial recrystallization occur in the high-strain sample during annealing at 650 °C for 1 h. For this sample, it is found that whereas coarsening alone results in a loss of strength with only a small gain in ductility, coarsening combined with pronounced partial recrystallization enables a combination of appreciably increased ductility and comparatively high strength

Effects of the Strain Rate Sensitivity and Strain Hardening on the Saturated Impulse of Plates

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Ling Zhu

Full Text Available Abstract This paper studies the stiffening effects of the material strain rate sensitivity and strain hardening on the saturated impulse of elastic, perfectly plastic plates. Finite element (FE code ABAQUS is employed to simulate the elastoplastic response of square plates under rectangular pressure pulse. Rigid-plastic analyses for saturated impulse, which consider strain rate sensitivity and strain hardening, are conducted. Satisfactory agreement between the finite element models (FEM and predictions of the rigid-plastic analysis is obtained, which verifies that the proposed rigid-plastic methods are effective to solve the problem including strain rate sensitivity and strain hardening. The quantitative results for the scale effect of the strain rate sensitivity are given. The results for the stiffening effects suggest that two general stiffening factors n 1 and n 2, which characterizes the strain rate sensitivity and strain hardening effect, respectively can be defined. The saturated displacement is inversely proportional to the stiffening factors (i.e. n 1 and n 2 and saturated impulse is inversely proportional to the square roots of the stiffening factors (i.e. n 1 and n 2. Formulae for displacement and saturated impulse are proposed based on the empirical analysis.

Enterobacterial repetitive intergenic consensus sequences and the PCR to generate fingerprints of genomic DNAs from Vibrio cholerae O1, O139, and non-O1 strains.

OpenAIRE

Rivera, I G; Chowdhury, M A; Huq, A; Jacobs, D; Martins, M T; Colwell, R R

1995-01-01

Enterobacterial repetitive intergenic consensus (ERIC) sequence polymorphism was studied in Vibrio Cholerae strains isolated before and after the cholera epidemic in Brazil (in 1991), along with epidemic strains from Peru, Mexico, and India, by PCR. A total of 17 fingerprint patterns (FPs) were detected in the V. cholerae strains examined; 96.7% of the toxigenic V. cholerae O1 strains and 100% of the O139 serogroup strains were found to belong to the same FP group comprising four fragments (F...

Microbial community dynamics during the bioremediation process of chlorimuron-ethyl-contaminated soil by Hansschlegelia sp. strain CHL1.

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Liqiang Yang

Full Text Available Long-term and excessive application of chlorimuron-ethyl has led to a series of environmental problems. Strain Hansschlegelia sp. CHL1, a highly efficient chlorimuron-ethyl degrading bacterium isolated in our previous study, was employed in the current soil bioremediation study. The residues of chlorimuron-ethyl in soils were detected, and the changes of soil microbial communities were investigated by phospholipid fatty acid (PLFA analysis. The results showed that strain CHL1 exhibited significant chlorimuron-ethyl degradation ability at wide range of concentrations between 10μg kg-1 and 1000μg kg-1. High concentrations of chlorimuron-ethyl significantly decreased the total concentration of PLFAs and the Shannon-Wiener indices and increased the stress level of microbes in soils. The inoculation with strain CHL1, however, reduced the inhibition on soil microbes caused by chlorimuron-ethyl. The results demonstrated that strain CHL1 is effective in the remediation of chlorimuron-ethyl-contaminated soil, and has the potential to remediate chlorimuron-ethyl contaminated soils in situ.

Microbial Community Dynamics during the Bioremediation Process of Chlorimuron-Ethyl-Contaminated Soil by Hansschlegelia sp. Strain CHL1

Science.gov (United States)

Yang, Liqiang; Li, Xinyu; Li, Xu; Su, Zhencheng; Zhang, Chenggang; Zhang, Huiwen

2015-01-01

Long-term and excessive application of chlorimuron-ethyl has led to a series of environmental problems. Strain Hansschlegelia sp. CHL1, a highly efficient chlorimuron-ethyl degrading bacterium isolated in our previous study, was employed in the current soil bioremediation study. The residues of chlorimuron-ethyl in soils were detected, and the changes of soil microbial communities were investigated by phospholipid fatty acid (PLFA) analysis. The results showed that strain CHL1 exhibited significant chlorimuron-ethyl degradation ability at wide range of concentrations between 10μg kg-1 and 1000μg kg-1. High concentrations of chlorimuron-ethyl significantly decreased the total concentration of PLFAs and the Shannon-Wiener indices and increased the stress level of microbes in soils. The inoculation with strain CHL1, however, reduced the inhibition on soil microbes caused by chlorimuron-ethyl. The results demonstrated that strain CHL1 is effective in the remediation of chlorimuron-ethyl-contaminated soil, and has the potential to remediate chlorimuron-ethyl contaminated soils in situ. PMID:25689050

Immunity status of adults and children against poliomyelitis virus type 1 strains CHAT and Sabin (LSc-2ab) in Germany.

Science.gov (United States)

Eggers, Maren; Terletskaia-Ladwig, Elena; Rabenau, Holger F; Doerr, Hans W; Diedrich, Sabine; Enders, Gisela; Enders, Martin

2010-12-09

In October 2007, the working group CEN/TC 216 of the European Committee for standardisation suggested that the Sabin oral poliovirus vaccine type 1 strain (LSc-2ab) presently used for virucidal tests should be replaced by another attenuated vaccine poliovirus type 1 strain, CHAT. Both strains were historically used as oral vaccines, but the Sabin type 1 strain was acknowledged to be more attenuated. In Germany, vaccination against poliomyelitis was introduced in 1962 using the oral polio vaccine (OPV) containing Sabin strain LSc-2ab. The vaccination schedule was changed from OPV to an inactivated polio vaccine (IPV) containing wild polio virus type 1 strain Mahoney in 1998. In the present study, we assessed potential differences in neutralising antibody titres to Sabin and CHAT in persons with a history of either OPV, IPV, or OPV with IPV booster. Neutralisation poliovirus antibodies against CHAT and Sabin 1 were measured in sera of 41 adults vaccinated with OPV. Additionally, sera from 28 children less than 10 years of age and immunised with IPV only were analysed. The neutralisation assay against poliovirus was performed according to WHO guidelines. The neutralisation activity against CHAT in adults with OPV vaccination history was significantly lower than against Sabin poliovirus type 1 strains (Wilcoxon signed-rank test P Sabin 1 varied between 8 and 64. Following IPV booster, anti-CHAT antibodies increased rapidly in sera of CHAT-negative adults with OPV history. Sera from children with IPV history neutralised CHAT and Sabin 1 strains equally. The lack of neutralising antibodies against the CHAT strain in persons vaccinated with OPV might be associated with an increased risk of reinfection with the CHAT polio virus type 1, and this implies a putative risk of transmission of the virus to polio-free communities. We strongly suggest that laboratory workers who were immunised with OPV receive a booster vaccination with IPV before handling CHAT in the laboratory.

Detection of Methylobacterium radiotolerans IMBG290 in potato plants by in situ hybridization

OpenAIRE

Pirttila A. M.; Kozyrovska N. O.; Ovcharenko L. P.; Podolich O. V.

2009-01-01

A new bacterial strain of pink-pigmented facultative methylotroph (M. radiotolerans IMBG290) which was previously isolated from in vitro grown potato plantlets after their inoculation with Pseudomonas fluorescens IMBG163 was detected in tissues by in situ hybridization method (ISH/FISH). The presence of Methylobacterium rRNA was observed in leaves and stems of potato plantlets, whereas no signal was detected in potato roots. The signal was less abundant in the untreated plants than in the pla...

Quantitative strain mapping of InAs/InP quantum dots with 1 nm spatial resolution using dark field electron holography

DEFF Research Database (Denmark)

Cooper, David; Rouviere, Jean-Luc; Béché, Armand

2011-01-01

The optical properties of semiconductor quantum dots are greatly influenced by their strain state. Dark field electron holography has been used to measure the strain in InAs quantum dots grown in InP with a spatial resolution of 1 nm. A strain value of 5.4%60.1% has been determined which...

Electronic Structures of Strained InAs x P1-x by Density Functional Theory.

Science.gov (United States)

Lee, Seung Mi; Kim, Min-Young; Kim, Young Heon

2018-09-01

We investigated the effects of strain on the electronic structures of InAsxP1-x using quantum mechanical density functional theory calculations. The electronic band gap and electron effective mass decreased with the increase of the uniaxial tensile strain along the [0001] direction of wurtzite InAs0.75P0.25. Therefore, faster electron movements are expected. These theoretical results are in good agreement with the experimental measurements of InAs0.75P0.25 nanowire.

ITS1/5.8S/ITS2, a Good Marker for Initial Classification of Shiitake Culinary-Medicinal Lentinus edodes (Agaricomycetes) Strains in China.

Science.gov (United States)

Song, Xiao-Xia; Zhao, Yan; Song, Chun-Yan; Li, Chuan-Hua; Song, Ying; Chen, Ming-Jie; Bao, Da-Peng; Tan, Qi

2018-01-01

China is home to rich wild and cultivated strains of Lentinus edodes, an important edible and medicinal mushroom. Artificial selection of L. edodes has a long history, and the widely cultivated strains belong to populations different from those of most wild strains. Internal transcribed spacer (ITS) regions have been used as good markers to identify L. edodes populations. But because ITS regions exhibit incomplete concerted evolution, the use of an ITS to identify L. edodes populations has been questioned. The objective of this study was to determine whether the ITS region is suitable for identifying L. edodes populations and which populations the widely cultivated strains and the most wild strains belong to by investigating intraindividual and differential ITS polymorphisms between 44 cultivars and 44 wild strains of L. edodes in China. Intraindividual ITS polymorphism is common in L. edodes strains, and most strains possessed 2 different ITS sequences, which came from their heterokaryons. The genetic polymorphisms of ITS1, 5.8S, and ITS2 in L. edodes strains are distinct. All strains were divided into one 5.8S type (5.8S-A), 2 ITS1 types (ITS1-A and ITS1-B), and 2 ITS2 types (ITS2-A and ITS2-B), which were subdivided into 2 branches (ITS2-A1 and ITS2-A2; ITS2-B1 and ITS2-B2). ITS1/5.8S/ITS2 could be used as a good marker in preliminary classification of L. edodes strains in China. It not only exhibited classified information of ITS1, 5.8S, and ITS2 for each strain at the same time, it also indicated whether the strain was heterozygous. The 44 cultivated strains were mainly the A/A/A1 type, and the 44 wild strains were mainly the A/A/A2 and other mixed types.

An information-motivation-behavioral skills analysis of diet and exercise behavior in Puerto Ricans with diabetes.

Science.gov (United States)

Osborn, Chandra Y; Rivet Amico, K; Fisher, William A; Egede, Leonard E; Fisher, Jeffrey D

2010-11-01

Frameworks are needed to inform diabetes self-care programs for diverse populations. We tested the Information-Motivation-Behavioral Skills (IMB) model in a sample of Puerto Ricans with Type 2 diabetes (N = 118). Structural equation models evaluated model fit and interrelations between IMB constructs. For diet behavior, information and motivation related to behavioral skills ( r = 0.19, p motivation related to behavioral skills (r = 0.53, p < .001), and behavioral skills related to behavior (r = 0.45, p < .001). The IMB model could inform interventions targeting these behaviors in diabetes.

Neutralizing antibodies against two HIV-1 strains in consecutively collected serum samples: cross neutralization and association to HIV-1 related disease

DEFF Research Database (Denmark)

Arendrup, M; Nielsen, C M; Hansen, J E

1992-01-01

97 sera collected during a 10-year period from 10 HIV-1 infected individuals were tested for neutralizing capacity against a virus isolate FICPH-22 obtained from a Danish AIDS patient, and the laboratory strain HTLV-IIIB. Three patterns of serum neutralizing activity were demonstrated: (a) patients...... developing high neutralizing activity against both HIV strains; (b) patients developing high neutralizing activity against the Danish virus isolate; and (c) patients developing only low titers of neutralizing antibodies (NA) against both HIV strains. The HTLV-IIIB strain was less sensitive to serum...... neutralization than the FICPH-22 isolate and the appearance of NA against HTLV-IIIB was typically lacking several years behind that against FICPH-22 indicating a broadening of the NA response over time. No difference in clinical outcome was observed comparing patients reaching high titers of NA and patients...

Strains of avian paramyxovirus type 1 of low pathogenicity for chickens isolated from poultry and wild birds in Denmark

DEFF Research Database (Denmark)

Jørgensen, Poul Henrik; Handberg, Kurt; Ahrens, Peter

2004-01-01

Twenty-one strains of avian paramyxovirus type 1 of low virulence for chickens were isolated in Denmark between 1996 and the beginning of 2003. The low virulence of the strains was demonstrated by sequencing the fusion (F) gene at the cleavage site motif and in some cases by determining the intra......Twenty-one strains of avian paramyxovirus type 1 of low virulence for chickens were isolated in Denmark between 1996 and the beginning of 2003. The low virulence of the strains was demonstrated by sequencing the fusion (F) gene at the cleavage site motif and in some cases by determining...

Amerindian Helicobacter pylori strains go extinct, as european strains expand their host range.

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Maria G Domínguez-Bello

Full Text Available We studied the diversity of bacteria and host in the H. pylori-human model. The human indigenous bacterium H. pylori diverged along with humans, into African, European, Asian and Amerindian groups. Of these, Amerindians have the least genetic diversity. Since niche diversity widens the sets of resources for colonizing species, we predicted that the Amerindian H. pylori strains would be the least diverse. We analyzed the multilocus sequence (7 housekeeping genes of 131 strains: 19 cultured from Africans, 36 from Spanish, 11 from Koreans, 43 from Amerindians and 22 from South American Mestizos. We found that all strains that had been cultured from Africans were African strains (hpAfrica1, all from Spanish were European (hpEurope and all from Koreans were hspEAsia but that Amerindians and Mestizos carried mixed strains: hspAmerind and hpEurope strains had been cultured from Amerindians and hpEurope and hpAfrica1 were cultured from Mestizos. The least genetically diverse H. pylori strains were hspAmerind. Strains hpEurope were the most diverse and showed remarkable multilocus sequence mosaicism (indicating recombination. The lower genetic structure in hpEurope strains is consistent with colonization of a diversity of hosts. If diversity is important for the success of H. pylori, then the low diversity of Amerindian strains might be linked to their apparent tendency to disappear. This suggests that Amerindian strains may lack the needed diversity to survive the diversity brought by non-Amerindian hosts.

Sparse "1"3C labelling for solid-state NMR studies of P. pastoris expressed eukaryotic seven-transmembrane proteins

International Nuclear Information System (INIS)

Liu, Jing; Liu, Chang; Fan, Ying; Munro, Rachel A.; Ladizhansky, Vladimir; Brown, Leonid S.; Wang, Shenlin

2016-01-01

We demonstrate a novel sparse "1"3C labelling approach for methylotrophic yeast P. pastoris expression system, towards solid-state NMR studies of eukaryotic membrane proteins. The labelling scheme was achieved by co-utilizing natural abundance methanol and specifically "1"3C labelled glycerol as carbon sources in the expression medium. This strategy improves the spectral resolution by 1.5 fold, displays site-specific labelling patterns, and has advantages for collecting long-range distance restraints for structure determination of large eukaryotic membrane proteins by solid-state NMR.

Evaluation test of high temperature strain gages used in a stethoscope for OGL-1 components in an elevated temperature service

Energy Technology Data Exchange (ETDEWEB)

Sato, Toshimi (Kyowa Electronic Inst. Co. Ltd. (Japan)); Tanaka, Isao; Komori, Yoshihiro; Suzuki; Toshiaki

1982-08-01

The stethoscope for OGL-1 components in a elevated temperature service (SOCETS) is a measuring system of evaluation integrity of structures for high temperature pipings during operations of Japan Material Testing Reactor. This paper is described about the results on fundamental performance on high temperature strain gages. From their test results that have been based on correlation of temperature-timestrain factors, it became clear that two weldable strain gages and a capacitance strain gage were available for strain measurements of OGL-1 components.

Enzyme markers in inbred rat strains: genetics of new markers and strain profiles.

Science.gov (United States)

Adams, M; Baverstock, P R; Watts, C H; Gutman, G A

1984-08-01

Twenty-six inbred strains of the laboratory rat (Rattus norvegicus) were examined for electrophoretic variation at an estimated 97 genetic loci. In addition to previously documented markers, variation was observed for the enzymes aconitase, aldehyde dehydrogenase, and alkaline phosphatase. The genetic basis of these markers (Acon-1, Ahd-2, and Akp-1) was confirmed. Linkage analysis between 35 pairwise comparisons revealed that the markers Fh-1 and Pep-3 are linked. The strain profiles of the 25 inbred strains at 11 electrophoretic markers are given.

Sequence analysis of Drd2, Drd4, and Dat1 in SHR and WKY rat strains

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Mill Jonathan

2005-12-01

Full Text Available Abstract Background The Spontaneously Hypertensive Rat (SHR shows a number of behaviours that closely parallel those seen in children with attention-deficit hyperactivity disorder. These include motor hyperactivity, excessive responses under a fixed-interval/extinction schedule, difficulty in acquiring operant tasks and increased sensitivity to immediate behavioural reinforcement. As in children with ADHD, the behavioural and cognitive deficits in the SHR are responsive to stimulants, including d-amphetamine and d,l-methylphenidate. The non-hyperactive Wistar Kyoto (WKY rat strain is often used as a control in behavioural studies of the SHR, and WKY itself has been suggested to be a useful animal model of depression. Numerous studies have shown that dopaminergic neurotransmission is altered between the two strains. Human genetic studies have found associations between several dopaminergic genes and both ADHD and depression. Methods We sequenced three candidate dopaminergic genes (Drd2, Drd4, and Dat1 in the SHR and WKY to identify between-strain sequence differences. Results No between-strain sequence differences were found in either Drd2 or Drd4, but several variations were found in the Dat1 gene that encodes the dopamine transporter. Conclusion It is plausible that DNA sequence changes in the Dat1 gene account for some of the behavioural differences observed between the SHR and WKY strains. Future work will focus on elucidating the functional effects of the observed polymorphisms.

Installation Restoration Program. Phase 2. Confirmation/Quantification. Stage 1 for Pease Air Force Base, New Hampshire. Volume 2. Appendices.

Science.gov (United States)

1987-08-01

san Agency Judgment on an amn pces that are more sensitive The .vlaldt’a . acca ~ble" siskieavel. . that those tested. Mortality to early life...METHOD -30 c 7P~4- 1]I07- .ps cC4 Zw /5(,ov 12򒵃 /I04dOSIT/ - RIEP PIIS Bi,0614 L 1 111 16" AL F6 t 7 9 2349, -* ,* I- ~CL */1.CIIIT C-CL).1- LI tNT I...LWpCL MAILSE ORIGINALD (.. .I hla REPRT 7e__ _ __ _ __ _ 1" -L 5.um.Iwf TOr4 c0opy 131210421, ( ^i F6 .,Ol+,3uicj.Imb3 COPYS 2L0 _______COLLCTEDB_____

A Novel Duplex Real-Time Reverse-Transcription PCR Assay for the Detection of Influenza A and the Novel Influenza A(H1N1 Strain

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Theo P. Sloots

2009-12-01

Full Text Available Timely implementation of antiviral treatment and other public health based responses are dependent on accurate and rapid diagnosis of the novel pandemic influenza A(H1N1 strain. In this study we developed a duplex real-time PCR (RT-PCR (dFLU-TM assay for the simultaneous detection of a broad range of influenza A subtypes and specific detection of the novel H1N1 2009 pandemic strain. The assay was compared to the combined results of two previously described monoplex RT-PCR assays using 183 clinical samples and 10 seasonal influenza A isolates. Overall, the results showed that the dFLU-TM RT-PCR method is suitable for detection of influenza A, including the novel H1N1 pandemic strain, in clinical samples.

Methanolobus psychrotolerans sp. nov., a psychrotolerant methanoarchaeon isolated from a saline meromictic lake in Siberia.

Science.gov (United States)

Chen, Sheng-Chung; Huang, Hsing-Hua; Lai, Mei-Chin; Weng, Chieh-Yin; Chiu, Hsiu-Hui; Tang, Sen-Lin; Rogozin, Denis Yu; Degermendzhy, Andrey G

2018-04-01

A psychrotolerant, methylotrophic methanogen, strain YSF-03 T , was isolated from the saline meromictic Lake Shira in Siberia. Cells of strain YSF-03 T were non-motile, irregular cocci and 0.8-1.2 µm in diameter. The methanogenic substrates utilized by strain YSF-03 T were methanol and trimethylamine. The temperature range of growth for strain YSF-03 T was from 0 to 37 °C. The optimum growth conditions were 30-37 °C, pH 7.0-7.4 and 0.17 M NaCl. The G+C content of the genome of strain YSF-03 T was 41.3 mol%. Phylogenetic analysis revealed that strain YSF-03 T was most closely related to Methanolobus profundi MobM T (98.15 % similarity in 16S rRNA gene sequence). Genome relatedness between strain YSF-03 T and MobM T was computed using the Genome-to-Genome Distance Calculator and average nucleotide identity, which gave values of 23.5 and 79.3 %, respectively. Based on the morphological, phenotypic, phylogenetic and genomic relatedness data presented here, it is evident that strain YSF-03 T represents a novel species of the genus Methanolobus, for which the name Methanolobus psychrotolerans sp. nov. is proposed. The type strain is YSF-03 T (=BCRC AR10049 T =DSM 104044 T =NBRC 112514 T ).

Evaluation test of high temperature strain gages used in a stethoscope for OGL-1 components in an elevated temperature service

International Nuclear Information System (INIS)

Sato, Toshimi; Tanaka, Isao; Komori, Yoshihiro; Suzuki; Toshiaki.

1982-01-01

The stethoscope for OGL-1 components in a elevated temperature service (SOCETS) is a measuring system of evaluation integrity of structures for high temperature pipings during operations of Japan Material Testing Reactor. This paper is described about the results on fundamental performance on high temperature strain gages. From their test results that have been based on correlation of temperature-timestrain factors, it became clear that two weldable strain gages and a capacitance strain gage were available for strain measurements of OGL-1 components. (author)

Immunity status of adults and children against poliomyelitis virus type 1 strains CHAT and Sabin (LSc-2ab in Germany

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Diedrich Sabine

2010-12-01

Full Text Available Abstract Background In October 2007, the working group CEN/TC 216 of the European Committee for standardisation suggested that the Sabin oral poliovirus vaccine type 1 strain (LSc-2ab presently used for virucidal tests should be replaced by another attenuated vaccine poliovirus type 1 strain, CHAT. Both strains were historically used as oral vaccines, but the Sabin type 1 strain was acknowledged to be more attenuated. In Germany, vaccination against poliomyelitis was introduced in 1962 using the oral polio vaccine (OPV containing Sabin strain LSc-2ab. The vaccination schedule was changed from OPV to an inactivated polio vaccine (IPV containing wild polio virus type 1 strain Mahoney in 1998. In the present study, we assessed potential differences in neutralising antibody titres to Sabin and CHAT in persons with a history of either OPV, IPV, or OPV with IPV booster. Methods Neutralisation poliovirus antibodies against CHAT and Sabin 1 were measured in sera of 41 adults vaccinated with OPV. Additionally, sera from 28 children less than 10 years of age and immunised with IPV only were analysed. The neutralisation assay against poliovirus was performed according to WHO guidelines. Results The neutralisation activity against CHAT in adults with OPV vaccination history was significantly lower than against Sabin poliovirus type 1 strains (Wilcoxon signed-rank test P Conclusion The lack of neutralising antibodies against the CHAT strain in persons vaccinated with OPV might be associated with an increased risk of reinfection with the CHAT polio virus type 1, and this implies a putative risk of transmission of the virus to polio-free communities. We strongly suggest that laboratory workers who were immunised with OPV receive a booster vaccination with IPV before handling CHAT in the laboratory.

Stereospecific oxidation of (R)- and (S)-1-indanol by naphthalene dioxygenase from Pseudomonas sp. strain NCIB 9816-4.

OpenAIRE

Lee, K; Resnick, S M; Gibson, D T

1997-01-01

A recombinant Escherichia coli strain which expresses naphthalene dioxygenase (NDO) from Pseudomonas sp. strain NCIB 9816-4 oxidized (S)-1-indanol to trans-(1S,3S)-indan-1,3-diol (95.5%) and (R)-3-hydroxy-1-indanone (4.5%). The same cells oxidized (R)-1-indanol to cis-1,3-indandiol (71%), (R)-3-hydroxy-1-indanone (18.2%), and cis-1,2,3-indantriol (10.8%). Purified NDO oxidized (S)-1-indenol to both syn- and anti-2,3-dihydroxy-1-indanol.

Stereospecific oxidation of (R)- and (S)-1-indanol by naphthalene dioxygenase from Pseudomonas sp. strain NCIB 9816-4.

Science.gov (United States)

Lee, K; Resnick, S M; Gibson, D T

1997-05-01

A recombinant Escherichia coli strain which expresses naphthalene dioxygenase (NDO) from Pseudomonas sp. strain NCIB 9816-4 oxidized (S)-1-indanol to trans-(1S,3S)-indan-1,3-diol (95.5%) and (R)-3-hydroxy-1-indanone (4.5%). The same cells oxidized (R)-1-indanol to cis-1,3-indandiol (71%), (R)-3-hydroxy-1-indanone (18.2%), and cis-1,2,3-indantriol (10.8%). Purified NDO oxidized (S)-1-indenol to both syn- and anti-2,3-dihydroxy-1-indanol.

Whole genome PCR scanning reveals the syntenic genome structure of toxigenic Vibrio cholerae strains in the O1/O139 population.

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Bo Pang

Full Text Available Vibrio cholerae is commonly found in estuarine water systems. Toxigenic O1 and O139 V. cholerae strains have caused cholera epidemics and pandemics, whereas the nontoxigenic strains within these serogroups only occasionally lead to disease. To understand the differences in the genome and clonality between the toxigenic and nontoxigenic strains of V. cholerae serogroups O1 and O139, we employed a whole genome PCR scanning (WGPScanning method, an rrn operon-mediated fragment rearrangement analysis and comparative genomic hybridization (CGH to analyze the genome structure of different strains. WGPScanning in conjunction with CGH revealed that the genomic contents of the toxigenic strains were conservative, except for a few indels located mainly in mobile elements. Minor nucleotide variation in orthologous genes appeared to be the major difference between the toxigenic strains. rrn operon-mediated rearrangements were infrequent in El Tor toxigenic strains tested using I-CeuI digested pulsed-field gel electrophoresis (PFGE analysis and PCR analysis based on flanking sequence of rrn operons. Using these methods, we found that the genomic structures of toxigenic El Tor and O139 strains were syntenic. The nontoxigenic strains exhibited more extensive sequence variations, but toxin coregulated pilus positive (TCP+ strains had a similar structure. TCP+ nontoxigenic strains could be subdivided into multiple lineages according to the TCP type, suggesting the existence of complex intermediates in the evolution of toxigenic strains. The data indicate that toxigenic O1 El Tor and O139 strains were derived from a single lineage of intermediates from complex clones in the environment. The nontoxigenic strains with non-El Tor type TCP may yet evolve into new epidemic clones after attaining toxigenic attributes.

Biodegradation of malathion by Bacillus licheniformis strain ML-1

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Khan Sara

2016-01-01

Full Text Available Malathion, a well-known organophosphate pesticide, has been used in agriculture over the last two decades for controlling pests of economically important crops. In the present study, a single bacterium, ML-1, was isolated by soil-enrichment technique and identified as Bacillus licheniformis on the basis of the 16S rRNA technique. The bacterium was grown in carbon-free minimal salt medium (MSM and was found to be very efficient in utilizing malathion as the sole source of carbon. Biodegradation experiments were performed in MSM without carbon source to determine the malathion degradation by the selected strain, and the residues of malathion were determined quantitatively using HPLC techniques. Bacillus licheniformis showed very promising results and efficiently consumed malathion as the sole carbon source via malathion carboxylesterase (MCE, and about 78% malathion was degraded within 5 days. The carboxylesterase activity was determined by using crude extract while using malathion as substrate, and the residues were determined by HPLC. It has been found that the MCE hydrolyzed 87% malathion within 96 h of incubation. Characterization of crude MCE revealed that the enzyme is robust in nature in terms of organic solvents, as it was found to be stable in various concentrations of ethanol and acetonitrile. Similarly, and it can work in a wide pH and temperature range. The results of this study highlighted the potential of Bacillus licheniformis strain ML-1 as a biodegrader that can be used for the bioremediation of malathion-contaminated soil.

Selective epitaxial growth properties and strain characterization of Si1- x Ge x in SiO2 trench arrays

Science.gov (United States)

Koo, Sangmo; Jang, Hyunchul; Ko, Dae-Hong

2017-04-01

In this study, we investigated the formation of a Si1- x Ge x fin structure in SiO2 trench arrays via an ultra-high-vacuum chemical-vapor deposition (UHV-CVD) selective epitaxial growth (SEG) process. Defect generation and microstructures of Si1- x Ge x fin structures with different Ge concentrations ( x = 0.2, 0.3 and 0.45) were examined. In addition, the strain evolution of a Si1- x Ge x fin structure was analyzed by using reciprocal space mapping (RSM). An (111) facet was formed from the Si1- x Ge x epi-layer and SiO2 trench wall interface to minimize the interface and the surface energy. The Si1- x Ge x fin structures were fully relaxed along the direction perpendicular to the trenches regardless of the Ge concentration. On the other hand, the fin structures were fully or partially strained along the direction parallel to the trenches depending on the Ge concentration: fully strained Si0.8Ge0.2 and Si0.7Ge0.3, and a Si0.55Ge0.45 strain-relaxed buffer. We further confirmed that the strain on the Si1- x Ge x fin structures remained stable after oxide removal and H2/N2 post-annealing.

Genome-Wide Transcription Study of Cryptococcus neoformans H99 Clinical Strain versus Environmental Strains.

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Elaheh Movahed

Full Text Available The infection of Cryptococcus neoformans is acquired through the inhalation of desiccated yeast cells and basidiospores originated from the environment, particularly from bird's droppings and decaying wood. Three environmental strains of C. neoformans originated from bird droppings (H4, S48B and S68B and C. neoformans reference clinical strain (H99 were used for intranasal infection in C57BL/6 mice. We showed that the H99 strain demonstrated higher virulence compared to H4, S48B and S68B strains. To examine if gene expression contributed to the different degree of virulence among these strains, a genome-wide microarray study was performed to inspect the transcriptomic profiles of all four strains. Our results revealed that out of 7,419 genes (22,257 probes examined, 65 genes were significantly up-or down-regulated in H99 versus H4, S48B and S68B strains. The up-regulated genes in H99 strain include Hydroxymethylglutaryl-CoA synthase (MVA1, Mitochondrial matrix factor 1 (MMF1, Bud-site-selection protein 8 (BUD8, High affinity glucose transporter 3 (SNF3 and Rho GTPase-activating protein 2 (RGA2. Pathway annotation using DAVID bioinformatics resource showed that metal ion binding and sugar transmembrane transporter activity pathways were highly expressed in the H99 strain. We suggest that the genes and pathways identified may possibly play crucial roles in the fungal pathogenesis.

Virulence of a Klebsiella pneumoniae strain carrying the New Delhi metallo-beta-lactamase-1 (NDM-1)

DEFF Research Database (Denmark)

Fuursted, Kurt; Schøler, Lone; Hansen, Frank

2011-01-01

, and in vitro virulence by assessing various virulence factors. The NDM-1 carrying K. pneumoniae isolate was the most virulent in the murine sepsis model but there was no clear cut correlation to in vitro virulence factors or killing in C. elegans. It is concluded that K. pneumoniae carrying NDM-1 have......The aim of the study was to compare and evaluate virulence in five strains of Klebsiella pneumoniae, including an isolate carrying New Delhi metallo-beta-lactamase-1 (NDM-1). In vivo virulence was assessed using a murine sepsis model and using the nematode Caenorhabditis elegans killing model...

Life Stress, Strain, and Deviance Across Schools: Testing the Contextual Version of General Strain Theory in China.

Science.gov (United States)

Zhang, Jinwu; Liu, Jianhong; Wang, Xin; Zou, Anquan

2017-08-01

General Strain Theory delineates different types of strain and intervening processes from strain to deviance and crime. In addition to explaining individual strain-crime relationship, a contextualized version of general strain theory, which is called the Macro General Strain Theory, has been used to analyze how aggregate variables influence aggregate and individual deviance and crime. Using a sample of 1,852 students (Level 1) nested in 52 schools (Level 2), the current study tests the Macro General Strain Theory using Chinese data. The results revealed that aggregate life stress and strain have influences on aggregate and individual deviance, and reinforce the individual stress-deviance association. The current study contributes by providing the first Macro General Strain Theory test based on Chinese data and offering empirical evidence for the multilevel intervening processes from strain to deviance. Limitations and future research directions are discussed.

Expression profiling of the VKORC1 and Calumenin gene in a Danish strain of bromadiolone-resistant Norway rats

DEFF Research Database (Denmark)

Markussen, Mette Drude; Heiberg, Ann-Charlotte; Fredholm, Merete

2008-01-01

in European strains of Norway rats while high hepatic levels of calumenin has been suggested responsible for resistance in an US strain of rats. To characterize the resistance mechanism in a Danish strain of bromadiolone-resistant Norway rats (with an Y139C-VKORC1 mutation), we compared VKORC1 and Calumenin......Anticoagulant resistance in Norway rats (Rattus norvegicus) has been associated with two genes, VKORC1 and Calumenin, which encodes proteins essential to the vitamin K-dependent gamma-carboxylation system. Mutations in the VKORC1 gene are considered the genetic basis for anticoagulant resistance...... liver gene expression between resistant and anticoagulant-susceptible rats upon saline and bromadiolone-administration. The resistant male and female rats had significantly lower constitutive VKORC1 expression (57 % and 63 %) compared to the susceptible rats (100 %) while the constitutive Calumenin...

Isolation and partial characterization of a new strain of Klebsiella pneumoniae capable of high 1,3 propanediol production from glycerol

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B. Sen

2015-04-01

Full Text Available Glycerol is a promising feedstock for microbial cultivation and production of 1,3 propanediol (1,3 PDO. Here we report a newly isolated bacterial strain BA11 from soil, capable of fermenting glycerol to 1,3 PDO, and has been identified to be a strain of Klebsiella pneumoniae. Strain BA11 was fast growing showing peak 1,3 PDO production in 6 h of cultivation with productivity of 1.2 g/L-h without the addition of Vitamin B12. Based on the optimum glycerol utilization (75% and 1,3 PDO production (8.3 g/L and yield (0.56 mol/mol glycerol utilized, the most appropriate glycerol concentration for cultivation was 20 g/L. The strain BA11 could tolerate the pH range of 6 to 8.5 as no inhibitory effects were seen on growth as well as 1,3 PDO production. Strain BA11 was most active and could produce high 1,3 PDO in the incubation temperature range of 25 to 40 oC. The production of 1,3 PDO was maximum (9.3 g/L under aerobic condition with 95.8% glycerol utilization. Addition of glucose to the glycerol fermentation led to increased cell mass but no improvement in the 1,3 PDO production.

Strain and strain rate by two-dimensional speckle tracking echocardiography in a maned wolf Strain e strain rate por meio de ecocardiogratia speckle traking bidimensional em um lobo-guará

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Matheus M. Mantovani

2012-12-01

Full Text Available The measurement of cardiovascular features of wild animals is important, as is the measurement in pets, for the assessment of myocardial function and the early detection of cardiac abnormalities, which could progress to heart failure. Speckle tracking echocardiography (2D STE is a new tool that has been used in veterinary medicine, which demonstrates several advantages, such as angle independence and the possibility to provide the early diagnosis of myocardial alterations. The aim of this study was to evaluate the left myocardial function in a maned wolf by 2D STE. Thus, the longitudinal, circumferential and radial strain and strain rate were obtained, as well as, the radial and longitudinal velocity and displacement values, from the right parasternal long axis four-chamber view, the left parasternal apical four chamber view and the parasternal short axis at the level of the papillary muscles. The results of the longitudinal variables were -13.52±7.88, -1.60±1.05, 4.34±2.52 and 3.86±3.04 for strain (%, strain rate (1/s, displacement (mm and velocity (cm/s, respectively. In addition, the radial and circumferential Strain and Strain rate were 24.39±14.23, 1.86±0.95 and -13.69±6.53, -1.01±0.48, respectively. Thus, the present study provides the first data regarding the use of this tool in maned wolves, allowing a more complete quantification of myocardial function in this species.A obtenção de parâmetros cardiovasculares em animais selvagens são importantes de serem avaliados, assim como em animais de companhia, para a obtenção da função miocárdica e determinação precoce de alterações cardíacas que poderiam evoluir para insuficiência cardíaca . A ecocardiografia speckle tracking (2D STE é uma ferramenta nova que tem sido utilizada em medicina veterinária, a qual tem demonstrado várias vantagens quanto ao seu uso, como a independência do ângulo de insonação e a possibilidade de se obter o diagnóstico precoce de altera

Raoultella sp. SM1, a novel iron-reducing and uranium-precipitating strain.

Science.gov (United States)

Sklodowska, Aleksandra; Mielnicki, Sebastian; Drewniak, Lukasz

2018-03-01

The main aim of this study was the characterisation of novel Raoutella isolate, an iron-reducing and uranium-precipitating strain, originating from microbial mats occurring in the sediments of a closed down uranium mine in Kowary (SW Poland). Characterisation was done in the context of its potential role in the functioning of these mats and the possibility to use them in uranium removal/recovery processes. In our experiment, we observed the biological precipitation of iron and uranium's secondary minerals containing oxygen, potassium, sodium and phosphor, which were identified as ningyoite-like minerals. The isolated strain, Raoultella sp. SM1, was also able to dissimilatory reduce iron (III) and uranium (VI) in the presence of citrate as an electron donor. Our studies allowed us to characterise a new strain which may be used as a model microorganism in the study of Fe and U respiratory processes and which may be useful in the bioremediation of uranium-contaminated waters and sediments. During this process, uranium may be immobilised in ningyoite-like minerals and can then be recovered in nano/micro-particle form, which may be easily transformed to uraninite. Copyright © 2017 Elsevier Ltd. All rights reserved.

Nitrogen Source Stabilization of Quorum Sensing in the Pseudomonas aeruginosa Bioaugmentation Strain SD-1.

Science.gov (United States)

Wang, Mei-Zhen; Lai, Bai-Min; Dandekar, Ajai A; Yang, Yu-Sheng; Li, Na; Yin, Jun; Shen, Dong-Sheng

2017-08-15

Pseudomonas aeruginosa SD-1 is efficient at degrading aromatic compounds and can therefore contribute to the bioremediation of wastewater. P. aeruginosa uses quorum sensing (QS) to regulate the production of numerous secreted "public goods." In wastewater bioaugmentation applications, there are myriad nitrogen sources, and we queried whether various nitrogen sources impact the stabilities of both QS and the bacterial populations. In a laboratory strain of P. aeruginosa , PAO1, the absence of a nitrogen source has been shown to destabilize these populations through the emergence of QS mutant "cheaters." We tested the ability of SD-1 to grow in casein broth, a condition that requires QS for growth, when the nitrogen source with either NH 4 Cl, NaNO 3 , or NaNO 2 or with no added nitrogen source. There was great variability in susceptibility to invasion by QS mutant cheaters and, by extension, the stability of the SD-1 population. When grown with NH 4 Cl as an extra nitrogen source, no population collapse was observed; by contrast, two-thirds of cultures grown in the presence of NaNO 2 collapsed. In the populations that collapsed, the frequency of social cheaters exceeded 40%. NaNO 3 and NaNO 2 directly favor QS mutants of P. aeruginosa SD-1. Although the mechanism by which these nitrogen sources act is not clear, these data indicate that the metabolism of nitrogen can affect the stability of bacterial populations, an important observation for continuing industrial applications with this species. IMPORTANCE Bioaugmentation as a method to help remediate wastewater pollutant streams holds significant potential to enhance traditional methods of treatment. Addition of microbes that can catabolize organic pollutants can be an effective method to remove several toxic compounds. Such bioaugmented strains of bacteria have been shown to be susceptible to competition from the microbiota that are present in wastewater streams, limiting their potential effectiveness. Here, we

Genetic Characterization of the Carotenoid Biosynthetic Pathway in Methylobacterium extorquens AM1 and Isolation of a Colorless Mutant

OpenAIRE

Van Dien, Stephen J.; Marx, Christopher J.; O'Brien, Brooke N.; Lidstrom, Mary E.

2003-01-01

Genomic searches were used to reconstruct the putative carotenoid biosynthesis pathway in the pink-pigmented facultative methylotroph Methylobacterium extorquens AM1. Four genes for putative phytoene desaturases were identified. A colorless mutant was obtained by transposon mutagenesis, and the insertion was shown to be in one of the putative phytoene desaturase genes. Mutations in the other three did not affect color. The tetracycline marker was removed from the original transposon mutant, r...

Characterization of field isolates of Suid herpesvirus 1 (Aujeszky's disease virus) as derivatives of attenuated vaccine strains

DEFF Research Database (Denmark)

Christensen, Laurids Siig; Medveczky, I.; Strandbygaard, Bertel

1992-01-01

Field isolates of suid herpesvirus 1 (Aujeszky's disease virus) from Poland and Hungary were identified by restriction fragment pattern analysis as derivatives of attenuated vaccine strains. The Polish isolates were found to be related to the BUK-TK-900 strain (Suivac A) which is widely used...

Isolation and characterization of butachlor-catabolizing bacterial strain Stenotrophomonas acidaminiphila JS-1 from soil and assessment of its biodegradation potential.

Science.gov (United States)

Dwivedi, S; Singh, B R; Al-Khedhairy, A A; Alarifi, S; Musarrat, J

2010-07-01

Isolation, characterization and assessment of butachlor-degrading potential of bacterial strain JS-1 in soil. Butachlor-degrading bacteria were isolated using enrichment culture technique. The morphological, biochemical and genetic characteristics based on 16S rDNA sequence homology and phylogenetic analysis confirmed the isolate as Stenotrophomonas acidaminiphila strain JS-1. The strain JS-1 exhibited substantial growth in M9 mineral salt medium supplemented with 3.2 mmol l(-1) butachlor, as a sole source of carbon and energy. The HPLC analysis revealed almost complete disappearance of butachlor within 20 days in soil at a rate constant of 0.17 day(-1) and half-life (t((1/2))) of 4.0 days, following the first-order rate kinetics. The strain JS-1 in stationary phase of culture also produced 21.0 microg ml(-1) of growth hormone indole acetic acid (IAA) in the presence of 500 microg ml(-1) of tryptophan. The IAA production was stimulated at lower concentrations of butachlor, whereas higher concentrations above 0.8 mmol l(-1) were found inhibitory. The isolate JS-1 characterized as Stenotrophomonas acidaminiphila was capable of utilizing butachlor as sole source of carbon and energy. Besides being an efficient butachlor degrader, it substantially produces IAA. The bacterial strain JS-1 has a potential for butachlor remediation with a distinctive auxiliary attribute of plant growth stimulation.

Swahili Learners' Views on the Need for a Monolingual Swahili ...

African Journals Online (AJOL)

This statement is valid today as it was in 1962 at the Bloomington Lexicogra- phy Conference. .... imb.ana v. 'sing to one another' ji.imb.ia v. ... learners of Swahili would be in a position to appreciate the questions on. Swahili grammar and the ...

Partner dependence and sexual risk behavior among STI clinic patients.

Science.gov (United States)

Senn, Theresa E; Carey, Michael P; Vanable, Peter A; Coury-Doniger, Patricia

2010-01-01

To investigate the relation between partner dependence and sexual risk behavior in the context of the information-motivation-behavioral skills (IMB) model. STI clinic patients (n = 1432) completed a computerized interview assessing partner dependence, condom use, and IMB variables. Men had higher partner-dependence scores than women did. Patients reporting greater dependence reported less condom use. Gender did not moderate the partner dependence-condom-use relationship. Partner dependence did not moderate the relation between IMB constructs and condom use. Further research is needed to determine how partner dependence can be incorporated into conceptual models of safer sex behaviors.

Electric-field-induced strain contributions in morphotropic phase boundary composition of (Bi{sub 1/2}Na{sub 1/2})TiO{sub 3}-BaTiO{sub 3} during poling

Energy Technology Data Exchange (ETDEWEB)

Khansur, Neamul H.; Daniels, John E. [School of Materials Science and Engineering, UNSW Australia, New South Wales 2052 (Australia); Hinterstein, Manuel [School of Materials Science and Engineering, UNSW Australia, New South Wales 2052 (Australia); Institute for Applied Materials, Karlsruhe Institute for Technology, P.O. Box 3640, 76021 Karlsruhe (Germany); Wang, Zhiyang [School of Materials Science and Engineering, UNSW Australia, New South Wales 2052 (Australia); The Australian Synchrotron, Clayton, Victoria 3168 (Australia); Groh, Claudia [Institute of Materials Science, Technische Universität Darmstadt, Alarich-Weiss-Straße 2, 64287 Darmstadt (Germany); Jo, Wook [School of Materials Science and Engineering, Ulsan National Institute of Science and Technology, Ulsan 44919 (Korea, Republic of)

2015-12-14

The microscopic contributions to the electric-field-induced macroscopic strain in a morphotropic 0.93(Bi{sub 1/2}Na{sub 1/2}TiO{sub 3})−0.07(BaTiO{sub 3}) with a mixed rhombohedral and tetragonal structure have been quantified using full pattern Rietveld refinement of in situ high-energy x-ray diffraction data. The analysis methodology allows a quantification of all strain mechanisms for each phase in a morphotropic composition and is applicable to use in a wide variety of piezoelectric compositions. It is shown that during the poling of this material 24%, 44%, and 32% of the total macroscopic strain is generated from lattice strain, domain switching, and phase transformation strains, respectively. The results also suggest that the tetragonal phase contributes the most to extrinsic domain switching strain, whereas the lattice strain primarily stems from the rhombohedral phase. The analysis also suggests that almost 32% of the total strain is lost or is a one-time effect due to the irreversible nature of the electric-field-induced phase transformation in the current composition. This information is relevant to on-going compositional development strategies to harness the electric-field-induced phase transformation strain of (Bi{sub 1/2}Na{sub 1/2})TiO{sub 3}-based lead-free piezoelectric materials for actuator applications.

Applying the information-motivation-behavioral skills model in medication adherence among Thai youth living with HIV: a qualitative study.

Science.gov (United States)

Rongkavilit, Chokechai; Naar-King, Sylvie; Kaljee, Linda M; Panthong, Apirudee; Koken, Juline A; Bunupuradah, Torsak; Parsons, Jeffrey T

2010-12-01

With disproportionately higher rates of HIV/AIDS among youth and increasing access to antiretroviral therapy (ART) in Thailand, there is a growing urgency in understanding the challenges to medication adherence confronting this population and in developing theory-based interventions to address these challenges. One potentially relevant model, the information-motivation-behavioral skills (IMB) model of adherence, was developed in Western settings characterized by a more individualistic culture in contrast to the more collectivistic culture of Thailand. We explored the application and adaptability of IMB on ART adherence among HIV-positive Thai youth through the analysis of qualitative data from a pilot motivational interviewing study. Twenty-two interview sessions from 10 HIV-positive Thai youth (17-24 years) were analyzed; 6 youth were on ART. Data support the utility of IMB as a potential framework for understanding ART adherence in this population. However, data indicate a consideration to expand the motivation construct of IMB to incorporate youths' perceived familial and social responsibilities and the need to adhere to medications for short- and long-term well-being of self, family, and society in a context of Buddhist values. These modifications to IMB could be relevant in other cultural settings with more collectivistic worldviews.

Applying the Information-Motivation-Behavioral Skills Model in Medication Adherence Among Thai Youth Living with HIV: A Qualitative Study

Science.gov (United States)

Naar-King, Sylvie; Kaljee, Linda M.; Panthong, Apirudee; Koken, Juline A.; Bunupuradah, Torsak; Parsons, Jeffrey T.

2010-01-01

Abstract With disproportionately higher rates of HIV/AIDS among youth and increasing access to antiretroviral therapy (ART) in Thailand, there is a growing urgency in understanding the challenges to medication adherence confronting this population and in developing theory-based interventions to address these challenges. One potentially relevant model, the information-motivation-behavioral skills (IMB) model of adherence, was developed in Western settings characterized by a more individualistic culture in contrast to the more collectivistic culture of Thailand. We explored the application and adaptability of IMB on ART adherence among HIV-positive Thai youth through the analysis of qualitative data from a pilot motivational interviewing study. Twenty-two interview sessions from 10 HIV-positive Thai youth (17–24 years) were analyzed; 6 youth were on ART. Data support the utility of IMB as a potential framework for understanding ART adherence in this population. However, data indicate a consideration to expand the motivation construct of IMB to incorporate youths' perceived familial and social responsibilities and the need to adhere to medications for short- and long-term well-being of self, family, and society in a context of Buddhist values. These modifications to IMB could be relevant in other cultural settings with more collectivistic worldviews. PMID:21091238

A wide extent of inter-strain diversity in virulent and vaccine strains of alphaherpesviruses.

Science.gov (United States)

Szpara, Moriah L; Tafuri, Yolanda R; Parsons, Lance; Shamim, S Rafi; Verstrepen, Kevin J; Legendre, Matthieu; Enquist, L W

2011-10-01

Alphaherpesviruses are widespread in the human population, and include herpes simplex virus 1 (HSV-1) and 2, and varicella zoster virus (VZV). These viral pathogens cause epithelial lesions, and then infect the nervous system to cause lifelong latency, reactivation, and spread. A related veterinary herpesvirus, pseudorabies (PRV), causes similar disease in livestock that result in significant economic losses. Vaccines developed for VZV and PRV serve as useful models for the development of an HSV-1 vaccine. We present full genome sequence comparisons of the PRV vaccine strain Bartha, and two virulent PRV isolates, Kaplan and Becker. These genome sequences were determined by high-throughput sequencing and assembly, and present new insights into the attenuation of a mammalian alphaherpesvirus vaccine strain. We find many previously unknown coding differences between PRV Bartha and the virulent strains, including changes to the fusion proteins gH and gB, and over forty other viral proteins. Inter-strain variation in PRV protein sequences is much closer to levels previously observed for HSV-1 than for the highly stable VZV proteome. Almost 20% of the PRV genome contains tandem short sequence repeats (SSRs), a class of nucleic acids motifs whose length-variation has been associated with changes in DNA binding site efficiency, transcriptional regulation, and protein interactions. We find SSRs throughout the herpesvirus family, and provide the first global characterization of SSRs in viruses, both within and between strains. We find SSR length variation between different isolates of PRV and HSV-1, which may provide a new mechanism for phenotypic variation between strains. Finally, we detected a small number of polymorphic bases within each plaque-purified PRV strain, and we characterize the effect of passage and plaque-purification on these polymorphisms. These data add to growing evidence that even plaque-purified stocks of stable DNA viruses exhibit limited sequence

Development of stable Vibrio cholerae O1 Hikojima type vaccine strains co-expressing the Inaba and Ogawa lipopolysaccharide antigens.

Directory of Open Access Journals (Sweden)

Stefan L Karlsson

Full Text Available We describe here the development of stable classical and El Tor V. cholerae O1 strains of the Hikojima serotype that co-express the Inaba and Ogawa antigens of O1 lipopolysaccharide (LPS. Mutation of the wbeT gene reduced LPS perosamine methylation and thereby gave only partial transformation into Ogawa LPS on the cell surface. The strains express approximately equal amounts of Inaba- and Ogawa-LPS antigens which are preserved after formalin-inactivation of the bacteria. Oral immunizations of both inbred and outbred mice with formalin-inactivated whole-cell vaccine preparations of these strains elicited strong intestinal IgA anti-LPS as well as serum vibriocidal antibody responses against both Inaba and Ogawa that were fully comparable to the responses induced by the licensed Dukoral vaccine. Passive protection studies in infant mice showed that immune sera raised against either of the novel Hikojima vaccine strains protected baby mice against infection with virulent strains of both serotypes. This study illustrates the power of using genetic manipulation to improve the properties of bacteria strains for use in killed whole-cell vaccines.

Pullulan-hyperproducing color variant strain of Aureobasidium pullulans FB-1 newly isolated from phylloplane of Ficus sp.

Science.gov (United States)

Singh, R S; Saini, G K

2008-06-01

The studies were carried out for the isolation of efficient pullulan producing strains of Aureobasidium pullulans. Five strains were isolated from phylloplane of different plants. Amongst these, three were producing black pigment melanin, while the remaining two produced pink pigment. These two color variant isolates of A. pullulans were designated as FB-1 and FG-1, and obtained from phylloplane of Ficus benjamina and Ficus glometa, respectively. The parameters employed for the identification of the isolates included morphology, nutritional assimilation patterns and exopolysaccharide (EPS) production. Isolates were compared with standard cultures for EPS production. A. pullulans FB-1 was the best producer of pullulan giving up to 1.9, 1.4 and 1.7 times more pullulan than the control of A. pullulans NCIM 976, NCIM 1048 and NCIM 1049, respectively. The IR spectra of the isolates and standard strains revealed that the polysaccharide was pullulan, but not aubasidan. The study also supported the fact that A. pullulans is a ubiquitous organism and phylloplane being the important niche of the organism.

Hydrogen-induced delayed cracking: 1. Strain energy effects on hydrogen solubility

International Nuclear Information System (INIS)

Puls, M.P.

1978-08-01

Based on Li, Oriani and Darken's derivation of the chemical potential of a solute in a stressed solid and Eshelby's method for obtaining the strain energy of solids containing coherent inhomogeneous inclusions, we have carried out a detailed theoretical analysis of the factors governing hydrogen solubility in stressed and unstressed zirconium and its alloys. Specifically, the analysis demonstrates the strong influence hydride self-stresses may have on the terminal solid solubility of hydrogen in zirconium. The self-energy arises due to the misfit strains between matrix and precipitate. We have calculated the total molal self-strain energy of some commonly observed δ and γ-hydride shapes and orientations. The magnitude of this energy is substantial. Thus for γ-hydride plates lying on basal planes, it is 4912 J/mol, while for γ-hydride needles with the needle axis parallel to the directions of the α-zirconium matrix, it is 2662 J/mol. This self-strain energy causes a shift in the terminal solid solubility. For example, at 77 o C, assuming fully constrained basal plane δ-hydride plates, the terminal solid solubility is increased 5.4 times over the stress-free case. We have also calculated the effect of external stress on the terminal solid solubility. This is governed by the interaction energy arising from the interaction of the applied stresses with the precipitate's misfit strain components. The interaction energy has been calculated for δ and γ-hydride plates and needles, taking full account of the anisotropy of the misfit. The interaction energy is negative for tensile applied stresses and, as a result of the anisotropic misfit, is texture-dependent. Its magnitude is small for most applied stresses but can achieve values of the order of the self-strain energy in the plastic zone of a plane-strain crack. We have also carried out a careful analysis of the solubility data of Kearns and Erickson and Hardie. This analysis is based partly on the theoretical

Segregation of genes from donor strain during the production of recombinant congenic strains.

Science.gov (United States)

van Zutphen, L F; Den Bieman, M; Lankhorst, A; Demant, P

1991-07-01

Recombinant congenic strains (RCS) constitute a set of inbred strains which are designed to dissect the genetic control of multigenic traits, such as tumour susceptibility or disease resistance. Each RCS contains a small fraction of the genome of a common donor strain, while the majority of genes stem from a common background strain. We tested at two stages of the inbreeding process in 20 RCS, derived from BALB/cHeA and STS/A, to see whether alleles from the STS/A donor strain are distributed over the RCS in a ratio as would theoretically be expected. Four marker genes (Pep-3; Pgm-1; Gpi-1 and Es-3) located at 4 different chromosomes were selected and the allelic distribution was tested after 3-4 and after 12 generations of inbreeding. The data obtained do not significantly deviate from the expected pattern, thus supporting the validity of the concept of RCS.

Microcystis aeruginos strain [D-Leu1] Mcyst-LR producer, from Buenos Aires province, Argentina

Directory of Open Access Journals (Sweden)

Lorena Rosso

2014-04-01

Full Text Available Objective: To show the toxicological and phylogenetic characterization of a native Microcystis aeruginosa (M. aeruginosa strain (named CAAT 2005-3 isolated from a water body of Buenos Aires province, Argentine. Methods: A M. aeruginosa strain was isolated from the drainage canal of the sewage treatment in the town of Pila, Buenos Aires province, Argentina and acclimated to laboratory conditions. The amplification of cpcBA-IGS Phcocyanin (PC, intergenic spacer and flanking regions was carried out in order to build a phylogenetic tree. An exactive/orbitrap mass spectrometer equipped with an electrospray ionization source (Thermo Fisher Scientific, Bremen, Germany was used for the LC/ESI-HRMS microcystins analysis. The number of cell/mL and [D-Leu1] Mcyst-LR production obtained as a function of time was modelled using the Gompertz equation. Results: The phylogenetic analysis showed that the sequence clustered with others M. aeruginosa sequences obtained from NCBI. The first Argentinian strain of M. aeruginosa (CAAT 2005-3 growing under culture conditions maintains the typical colonial architecture of M. aeruginosa with profuse mucilage. M. aeruginosa CAAT 2005-3 expresses a toxin variant, that was identified by LC-HRMS/Orbitrapas as [D-Leu1] microcystin-LR ([M+H]+=1 037.8 m/z. Conclusions: [D-Leu1] microcystin-LR has been also detected in M. aeruginosa samples from Canada, Brazil and Argentina. This work provides the basis for technological development and production of analytical standards of toxins present in our region.

Parental Information, Motivation, and Behavioral Skills Correlate with Child Sweetened Beverage Consumption

Science.gov (United States)

Goodell, L. Suzanne; Pierce, Michelle B.; Amico, K. Rivet; Ferris, Ann M.

2012-01-01

Objective: To evaluate fit of the Information-Motivation-Behavioral Skills (IMB) model applied to sweetened beverage (SB) consumption in children. Design: Cross-sectional. Parents completed a home beverage inventory and IMB survey regarding SB consumption. Setting: Health fairs, Special Supplemental Nutrition Program for Women, Infants, and…

Thermoresistant revertants of an Escherichia coli strain carrying tif-1 and ruv mutations: non-suppressibility of ruv by sfi

International Nuclear Information System (INIS)

Otsuji, N.; Iyehara-Ogawa, H.

1979-01-01

Spontaneous thermoresistant revertants were isolated from Tif1 Ruv - and Tif1 Ruv + strains of Escherichia coli K-12. They were divided into five groups; backmutants to tif + and recA structural gene mutants accounted for at least two of these groups. Mutations with an unconditional RecA - phenotype were detected at a higher frequency in the Tif1 Ruv - strains (65%) than in the Tif1 Ruv + strains (25%). A third group consisted of revertants exhibiting a RecA - phenotype at low temperature. Revertants with normal recombination ability and uv resistance, but with a thermosensitive defect in propagating lambda bio11 phage, were also isolated (group 4). The alleles responsible for this property were cotransducible with the srl gene, suggesting that they are located at the recA locus. Other revertants, which might carry lexA, lexB, or zab mutations, were uv sensitive and were able to propagate lambda bio11 phage (group 5). The sfi mutation, which suppresses filamentation in the Tif1 and uv-sensitive Lon - strains, does not restore uv resistance of the Ruv - mutant

Genomic Comparison of Escherichia coli K1 Strains Isolated from the Cerebrospinal Fluid of Patients with Meningitis †

OpenAIRE

Yao, Yufeng; Xie, Yi; Kim, Kwang Sik

2006-01-01

Escherichia coli is a major cause of enteric/diarrheal diseases, urinary tract infections, and sepsis. E. coli K1 is the leading gram-negative organism causing neonatal meningitis, but the microbial basis of E. coli K1 meningitis is incompletely understood. Here we employed comparative genomic hybridization to investigate 11 strains of E. coli K1 isolated from the cerebrospinal fluid (CSF) of patients with meningitis. These 11 strains cover the majority of common O serotypes in E. coli K1 iso...

The mechanism of Lactobacillus strains for their ability to remove fumonisins B1 and B2.

Science.gov (United States)

Zhao, Hongfei; Wang, Xiao; Zhang, Junwen; Zhang, Jun; Zhang, Bolin

2016-11-01

Two Lactobacillus strains, L. plantarum B7 and L. pentosus X8, exhibited high efficiency in removing fumonisins (FB1 and FB2) from aqueous medium. 52.9% FB1 and 85.2% FB2 were bound by L. plantarum B7, and 58.0% FB1 and 86.5% FB2 by L. pentosus X8, respectively. Temperature, incubation time, and pH affected the binding ability of two strains. Cell viability was not necessary for the binding ability. The various components of cell wall were determined for their ability to absorb FBS. The results revealed that the intact peptidoglycans exhibited the greatest capacity in binding FBs. Especially the better structural integrity of the peptidoglycans the more FBs was bound. Thus, the absorption of two bacterial cells to FBs is proposed to be a physical process, and peptidoglycans should be the main binding site. Additionally, Caco-2 cell lines were used to evaluate the ability of the two strains to reduce the damage of FBs in vitro. Caco-2 cell's death was reduced after the cell lines were subjected to both viable and non-viable L. pentosus X8, respectively. The two Lactobacillus strains might be used as a biological detoxification for the removal of FBs from diet and feed in the future. Copyright © 2016 Elsevier Ltd. All rights reserved.

Clostridium geopurificans strain MJ1 sp. nov., a strictly anaerobic bacterium that grows via fermentation and reduces the cyclic nitramine explosive hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX).

Science.gov (United States)

Kwon, Man Jae; Wei, Na; Millerick, Kayleigh; Popovic, Jovan; Finneran, Kevin

2014-06-01

A fermentative, non-spore forming, motile, rod-shaped bacterium, designated strain MJ1(T), was isolated from an RDX contaminated aquifer at a live-fire training site in Northwest NJ, United States. On the basis of 16S rRNA gene sequencing and DNA base composition, strain MJ1(T) was assigned to the Firmicutes. The DNA G+C content was 42.8 mol%. Fermentative growth was supported by glucose and citrate in a defined basal medium. The bacterium is a strict anaerobe that grows between at pH 6.0 and pH 8.0 and 18 and 37 °C. The culture did not grow with hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) as the electron acceptor or mineralize RDX under these conditions. However, MJ1(T) transformed RDX into MNX, methylenedinitramine, formaldehyde, formate, ammonium, nitrous oxide, and nitrate. The nearest phylogenetic relative with a validly published name was Desulfotomaculum guttoideum (95 % similarity). However, MJ1(T) was also related to Clostridium celerecrescens DSM 5628 (95 %), Clostridium indolis DSM 755 (94 %), and Clostridium sphenoides DSM 632 (94 %). DNA:DNA hybridization with these strains was between 6.7 and 58.7 percent. The dominant cellular fatty acids (greater than 5 % of the total, which was 99.0 % recovery) were 16:0 fatty acid methyl ester (FAME) (32.12 %), 18:1cis 11 dimethyl acetal (DMA) (16.47 %), 16:1cis 9 DMA (10.28 %), 16:1cis 9 FAME (8.10 %), and 18:1cis 9 DMA (5.36 %). On the basis of morphological, physiological, and phylogenetic data, Clostridium geopurificans is proposed as a new species in genus Clostridium, with strain MJ1(T) as the type strain.

Organization of nif gene cluster in Frankia sp. EuIK1 strain, a symbiont of Elaeagnus umbellata.

Science.gov (United States)

Oh, Chang Jae; Kim, Ho Bang; Kim, Jitae; Kim, Won Jin; Lee, Hyoungseok; An, Chung Sun

2012-01-01

The nucleotide sequence of a 20.5-kb genomic region harboring nif genes was determined and analyzed. The fragment was obtained from Frankia sp. EuIK1 strain, an indigenous symbiont of Elaeagnus umbellata. A total of 20 ORFs including 12 nif genes were identified and subjected to comparative analysis with the genome sequences of 3 Frankia strains representing diverse host plant specificities. The nucleotide and deduced amino acid sequences showed highest levels of identity with orthologous genes from an Elaeagnus-infecting strain. The gene organization patterns around the nif gene clusters were well conserved among all 4 Frankia strains. However, characteristic features appeared in the location of the nifV gene for each Frankia strain, depending on the type of host plant. Sequence analysis was performed to determine the transcription units and suggested that there could be an independent operon starting from the nifW gene in the EuIK strain. Considering the organization patterns and their total extensions on the genome, we propose that the nif gene clusters remained stable despite genetic variations occurring in the Frankia genomes.

Strain tolerance of Bi2Sr2Ca1Cu2O8-δ/Ag composites at high field

International Nuclear Information System (INIS)

Li, Q.; Ostenson, J.E.; Finnemore, D.K.

1991-01-01

Strain tolerance of Bi 2 Sr 2 Ca 1 Cu 2 O 8-δ /Ag composites have been studied at fields up to 20 T and bending strains up to 2.6% in order to determine the factors that control the critical current density. The goal is to find the best way to distribute Ag such as to give both high strain tolerance and high critical current density. Partial melt processed samples prepared from micromilled mixtures containing 30% Ag by volume show a gradually decreasing critical current all the way out to 2.6% strain. Samples typically show about 1000 A/cm 2 at 4.2 K, 20 T, and 0.75% strain. At 20 K, these values occur at 4 T and 0.75% strain

Anisotropic Raman scattering and mobility in monolayer 1T_d-ReS_2 controlled by strain engineering

International Nuclear Information System (INIS)

Zhou, Z.H.; Wei, B.C.; He, C.Y.; Min, Y.M.; Chen, C.H.; Liu, L.Z.; Wu, X.L.

2017-01-01

Highlights: • Symmetry breaking is achieved by strain that modulates the band structure and carrier population. • Mobility cunt-on rate can be enhanced by structural transformation. • The angle-dependent Raman spectrum of A_g-like, E_g-like and C_p models are used to discriminate and analysis structural anisotropy. • Strain engineering is a useful method to design the anisotropic Raman scattering and mobility. - Abstract: Regulation of electronic structure and mobility cut-on rate in two-dimensional transition metal dichalcogenides (TMDs) has attracted much attention because of its potential in electronic device design. The anisotropic Raman scattering and mobility cut-on rate of monolayer unique distorted-1T (1T_d) ReS_2 with external strain are determined theoretically based on the density function theory. The angle-dependent Raman spectrum of A_g-like, E_g-like and C_p models are used to discriminate and analysis structural anisotropy; the strain is exploited to adjust the structural symmetry and electronic structure of ReS_2 so as to enhance mobility cut-on rate to almost 6 times of the original value. Our results suggest the use of the strain engineering in high-quality semiconductor switch device.

Large Scale Genome Analysis Shows that the Epitopes for Broadly Cross-Reactive Antibodies Are Predominant in the Pandemic 2009 Influenza Virus A H1N1 Strain

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Edgar E. Lara-Ramírez

2013-11-01

Full Text Available The past pandemic strain H1N1 (A (H1N1pdm09 has now become a common component of current seasonal influenza viruses. It has changed the pre-existing immunity of the human population to succeeding infections. In the present study, a total of 14,210 distinct sequences downloaded from National Center for Biotechnology Information (NCBI database were used for the analysis. The epitope compositions in A (H1N1pdm09, classic seasonal strains, swine strains as well as highly virulent avian strain H5N1, identified with the aid of the Immune Epitope DataBase (IEDB, were compared at genomic level. The result showed that A (H1N1 pdm09 contains the 90% of B-cell epitopes for broadly cross-reactive antibodies (EBCA, which is in consonance with the recent reports on the experimental identification of new epitopes or antibodies for this virus and the binding tests with influenza virus protein HA of different subtypes. Our analysis supports that high proportional EBCA depends on the epitope pattern of A (H1N1pdm09 virus. This study may be helpful for better understanding of A (H1N1pdm09 and the production of new influenza vaccines.

In planta gene expression analysis of Xanthomonas oryzae pathovar oryzae, African strain MAI1

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Verdier Valérie

2010-06-01

Full Text Available Abstract Background Bacterial leaf blight causes significant yield losses in rice crops throughout Asia and Africa. Although both the Asian and African strains of the pathogen, Xanthomonas oryzae pv. oryzae (Xoo, induce similar symptoms, they are nevertheless genetically different, with the African strains being more closely related to the Asian X. oryzae pv. oryzicola (Xoc. Results Changes in gene expression of the African Xoo strain MAI1 in the susceptible rice cultivar Nipponbare were profiled, using an SSH Xoo DNA microarray. Microarray hybridization was performed comparing bacteria recovered from plant tissues at 1, 3, and 6 days after inoculation (dai with bacteria grown in vitro. A total of 710 bacterial genes were found to be differentially expressed, with 407 up-regulated and 303 down-regulated. Expression profiling indicated that less than 20% of the 710 bacterial transcripts were induced in the first 24 h after inoculation, whereas 63% were differentially expressed at 6 dai. The 710 differentially expressed genes were one-end sequenced. 535 sequences were obtained from which 147 non-redundant sequences were identified. Differentially expressed genes were related to metabolism, secretion and transport, pathogen adherence to plant tissues, plant cell-wall degradation, IS elements, and virulence. In addition, various other genes encoding proteins with unknown function or showing no similarity to other proteins were also induced. The Xoo MAI1 non-redundant set of sequences was compared against several X. oryzae genomes, revealing a specific group of genes that was present only in MAI1. Numerous IS elements were also found to be differentially expressed. Quantitative real-time PCR confirmed 86% of the identified profile on a set of 14 genes selected according to the microarray analysis. Conclusions This is the first report to compare the expression of Xoo genes in planta across different time points during infection. This work shows that

Genome sequence of Shigella flexneri strain SP1, a diarrheal isolate that encodes an extended-spectrum β-lactamase (ESBL).

Science.gov (United States)

Shen, Ping; Fan, Jianzhong; Guo, Lihua; Li, Jiahua; Li, Ang; Zhang, Jing; Ying, Chaoqun; Ji, Jinru; Xu, Hao; Zheng, Beiwen; Xiao, Yonghong

2017-05-12

Shigellosis is the most common cause of gastrointestinal infections in developing countries. In China, the species most frequently responsible for shigellosis is Shigella flexneri. S. flexneri remains largely unexplored from a genomic standpoint and is still described using a vocabulary based on biochemical and serological properties. Moreover, increasing numbers of ESBL-producing Shigella strains have been isolated from clinical samples. Despite this, only a few cases of ESBL-producing Shigella have been described in China. Therefore, a better understanding of ESBL-producing Shigella from a genomic standpoint is required. In this study, a S. flexneri type 1a isolate SP1 harboring bla CTX-M-14 , which was recovered from the patient with diarrhea, was subjected to whole genome sequencing. The draft genome assembly of S. flexneri strain SP1 consisted of 4,592,345 bp with a G+C content of 50.46%. RAST analysis revealed the genome contained 4798 coding sequences (CDSs) and 100 RNA-encoding genes. We detected one incomplete prophage and six candidate CRISPR loci in the genome. In vitro antimicrobial susceptibility testing demonstrated that strain SP1 is resistant to ampicillin, amoxicillin/clavulanic acid, cefazolin, ceftriaxone and trimethoprim. In silico analysis detected genes mediating resistance to aminoglycosides, β-lactams, phenicol, tetracycline, sulphonamides, and trimethoprim. The bla CTX-M-14 gene was located on an IncFII2 plasmid. A series of virulence factors were identified in the genome. In this study, we report the whole genome sequence of a bla CTX-M-14 -encoding S. flexneri strain SP1. Dozens of resistance determinants were detected in the genome and may be responsible for the multidrug-resistance of this strain, although further confirmation studies are warranted. Numerous virulence factors identified in the strain suggest that isolate SP1 is potential pathogenic. The availability of the genome sequence and comparative analysis with other S

[Molecular epidemiological characteristics of HIV-1 strains isolated from newly diagnosed MSM subjects (2006-2010) in Beijing, China].

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Ye, Jing-Rong; Zang, Wan-Chun; Su, Xue-Li; Lu, Hong-Yan; Hao, Ming-Qiang; Xin, Ruo-Lei; Chen, Guo-Min; He, Xiong; Zeng, Yi

2014-03-01

This study aims to analyze the molecular epidemiological characteristics of HIV-1 strains prevailing among men who have sex with men (MSM) in Beijing, China. The pol gene fragments from 250 newly diagnosed HIV-1-infected MSM individuals during 2006-2010 in Beijing were amplified by RT-nested PCR, sequenced, and phylogenetically analyzed. HIV-1 pol gene from 189 individuals were amplified and analyzed; 81 (42. 9%), 3 (1. 6%), 2 (1.0%), 88 (46. 6%), and 15 (7.9%) individuals were infected with HIV-1 subtypes B, B', C, CRF01_AE, and CRF07_BC, respectively. The subtypes B and CRF01_AE could both be grouped into two clusters, and CRFO7_BC strains shared high homology and were presumed to originate from a common ancestor. The HIV-1 circulating in MSM in Beijing had a lower genetic diversity than in heterosexuals. The HIV-1 epidemic (2006-2010) in MSM in Beijing was actually a rapid spread of HIV-1 CRF01 AE and B, or rather native strains of the two viruses.

Strain and strain rate by two-dimensional speckle tracking echocardiography in a maned wolf

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Matheus M. Mantovani

2012-12-01

Full Text Available The measurement of cardiovascular features of wild animals is important, as is the measurement in pets, for the assessment of myocardial function and the early detection of cardiac abnormalities, which could progress to heart failure. Speckle tracking echocardiography (2D STE is a new tool that has been used in veterinary medicine, which demonstrates several advantages, such as angle independence and the possibility to provide the early diagnosis of myocardial alterations. The aim of this study was to evaluate the left myocardial function in a maned wolf by 2D STE. Thus, the longitudinal, circumferential and radial strain and strain rate were obtained, as well as, the radial and longitudinal velocity and displacement values, from the right parasternal long axis four-chamber view, the left parasternal apical four chamber view and the parasternal short axis at the level of the papillary muscles. The results of the longitudinal variables were -13.52±7.88, -1.60±1.05, 4.34±2.52 and 3.86±3.04 for strain (%, strain rate (1/s, displacement (mm and velocity (cm/s, respectively. In addition, the radial and circumferential Strain and Strain rate were 24.39±14.23, 1.86±0.95 and -13.69±6.53, -1.01±0.48, respectively. Thus, the present study provides the first data regarding the use of this tool in maned wolves, allowing a more complete quantification of myocardial function in this species.

Construction of insertion and deletion mxa mutants of Methylobacterium extorquens AM1 by electroporation.

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Toyama, H; Anthony, C; Lidstrom, M E

1998-09-01

Methylobacterium extorquens AM1 is a pink-pigmented facultative methylotroph which is widely used for analyzing pathways of C1 metabolism with biochemical and molecular biological techniques. To facilitate this approach, we have applied a new method to construct insertion or disruption mutants with drug resistance genes by electroporation. By using this method, mutants were obtained in four genes present in the mxa methylotrophy gene cluster for which the functions were unknown, mxaR, mxaS, mxaC and mxaD. These mutants were unable to grow on methanol except the mutant of mxaD, which showed reduced growth on methanol.

Biological Efficacy of Streptomyces sp. Strain BN1 against the Cereal Head Blight Pathogen Fusarium graminearum

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Boknam Jung

2013-03-01

Full Text Available Fusarium head blight (FHB caused by the filamentous fungus Fusarium graminearum is one of the most severe diseases threatening the production of small grains. Infected grains are often contaminated with mycotoxins such as zearalenone and trichothecences. During survey of contamination by FHB in rice grains, we found a bacterial isolate, designated as BN1, antagonistic to F. graminearum. The strain BN1 had branching vegetative hyphae and spores, and its aerial hyphae often had long, straight filaments bearing spores. The 16S rRNA gene of BN1 had 100% sequence identity with those found in several Streptomyces species. Phylogenetic analysis of ITS regions showed that BN1 grouped with S. sampsonii with 77% bootstrap value, suggesting that BN1 was not a known Streptomyces species. In addition, the efficacy of the BN1 strain against F. graminearum strains was tested both in vitro and in vivo. Wheat seedling length was significantly decreased by F. graminearum infection. However, this effect was mitigated when wheat seeds were treated with BN1 spore suspension prior to F. graminearum infection. BN1 also significantly decreased FHB severity when it was sprayed onto wheat heads, whereas BN1 was not effective when wheat heads were point inoculated. These results suggest that spraying of BN1 spores onto wheat heads during the wheat flowering season can be efficient for plant protection. Mechanistic studies on the antagonistic effect of BN1 against F. graminearum remain to be analyzed.

Identification of pOENI-1 and Related Plasmids in Oenococcus oeni Strains Performing the Malolactic Fermentation in Wine

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Favier, Marion; Bilhère, Eric; Lonvaud-Funel, Aline; Moine, Virginie; Lucas, Patrick M.

2012-01-01

Plasmids in lactic acid bacteria occasionally confer adaptive advantages improving the growth and behaviour of their host cells. They are often associated to starter cultures used in the food industry and could be a signature of their superiority. Oenococcus oeni is the main lactic acid bacteria species encountered in wine. It performs the malolactic fermentation that occurs in most wines after alcoholic fermentation and contributes to their quality and stability. Industrial O. oeni starters may be used to better control malolactic fermentation. Starters are selected empirically by virtue of their fermentation kinetics and capacity to survive in wine. This study was initiated with the aim to determine whether O. oeni contains plasmids of technological interest. Screening of 11 starters and 33 laboratory strains revealed two closely related plasmids, named pOENI-1 (18.3-kb) and pOENI-1v2 (21.9-kb). Sequence analyses indicate that they use the theta mode of replication, carry genes of maintenance and replication and two genes possibly involved in wine adaptation encoding a predicted sulphite exporter (tauE) and a NADH:flavin oxidoreductase of the old yellow enzyme family (oye). Interestingly, pOENI-1 and pOENI-1v2 were detected only in four strains, but this included three industrial starters. PCR screenings also revealed that tauE is present in six of the 11 starters, being probably inserted in the chromosome of some strains. Microvinification assays performed using strains with and without plasmids did not disclose significant differences of survival in wine or fermentation kinetics. However, analyses of 95 wines at different phases of winemaking showed that strains carrying the plasmids or the genes tauE and oye were predominant during spontaneous malolactic fermentation. Taken together, the results revealed a family of related plasmids associated with industrial starters and indigenous strains performing spontaneous malolactic fermentation that possibly

Empirical Validation of the Information–Motivation–Behavioral Skills Model of Diabetes Medication Adherence: A Framework for Intervention

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Mayberry, Lindsay S.; Osborn, Chandra Y.

2014-01-01

OBJECTIVE Suboptimal adherence to diabetes medications is prevalent and associated with unfavorable health outcomes, but it remains unclear what intervention content is necessary to effectively promote medication adherence in diabetes. In other disease contexts, the Information–Motivation–Behavioral skills (IMB) model has effectively explained and promoted medication adherence and thus may have utility in explaining and promoting adherence to diabetes medications. We tested the IMB model’s hypotheses in a sample of adults with type 2 diabetes. RESEARCH DESIGN AND METHODS Participants (N = 314) completed an interviewer-administered survey and A1C test. Structural equation models tested the effects of diabetes medication adherence-related information, motivation, and behavioral skills on medication adherence and the effect of medication adherence on A1C. RESULTS The IMB elements explained 41% of the variance in adherence, and adherence explained 9% of the variance in A1C. As predicted, behavioral skills had a direct effect on adherence (β = 0.59; P motivation (indirect effect 0.12 [0.05–0.20]) on adherence. Medication adherence significantly predicted glycemic control (β = −0.30; P motivation, and behavioral skills and assessing the degree to which change in these determinants leads to changes in medication adherence behavior. PMID:24598245

Empirical validation of the information-motivation-behavioral skills model of diabetes medication adherence: a framework for intervention.

Science.gov (United States)

Mayberry, Lindsay S; Osborn, Chandra Y

2014-01-01

Suboptimal adherence to diabetes medications is prevalent and associated with unfavorable health outcomes, but it remains unclear what intervention content is necessary to effectively promote medication adherence in diabetes. In other disease contexts, the Information-Motivation-Behavioral skills (IMB) model has effectively explained and promoted medication adherence and thus may have utility in explaining and promoting adherence to diabetes medications. We tested the IMB model's hypotheses in a sample of adults with type 2 diabetes. Participants (N = 314) completed an interviewer-administered survey and A1C test. Structural equation models tested the effects of diabetes medication adherence-related information, motivation, and behavioral skills on medication adherence and the effect of medication adherence on A1C. The IMB elements explained 41% of the variance in adherence, and adherence explained 9% of the variance in A1C. As predicted, behavioral skills had a direct effect on adherence (β = 0.59; P information (indirect effect 0.08 [0.01-0.15]) and motivation (indirect effect 0.12 [0.05-0.20]) on adherence. Medication adherence significantly predicted glycemic control (β = -0.30; P information, motivation, and behavioral skills and assessing the degree to which change in these determinants leads to changes in medication adherence behavior.

5-Fluorouracil-resistant strain of Methanobacterium thermoautortrophicum

International Nuclear Information System (INIS)

Nagle, D.P. Jr.; Teal, R.; Eisenbraun, A.

1987-01-01

Growth of Methanobacterium thermoautotrophicum Marburg is inhibited by the pyrimidine, 5-fluorouracil (FU). It was shown previously that methanogenesis is not inhibited to the same extent as growth. A spontaneously occurring FU-resistant strain (RTAE-1) was isolated from a culture of strain Marburg. The growth of both strains was inhibited by 5-fluorodeoxyuridine but not 5-fluorocytosine, and the wild type was more susceptible to inhibition by 5-azauracil and 6-azauracil than was strain RTAE-1. The cellular targets for the pyrimidine analogs are not known. When the accumulation of 14 C-labeled uracil or FU by the two strains was compared, the wilt type took up 15-fold more radiolabel per cell than did the FU-resistant strain. In the wild type, radiolabel from uracil was incorporated into the soluble pool, RNA, and DNA. The metabolism of uracil appeared to involve a uracil phosphoribosyltransferase activity. Strain Marburg extracts contained this enzyme, whereas FU-resistant strain RTAE-1 extracts had less than 1/10 as much activity. Although it is possible that a change in permeability to the compounds plays a role in the stable resistance of strain RTAE-1, the fact that it lacks the ability to metabolize pyrimidines to nucleotides is sufficient to account for its phenotype