WorldWideScience

Sample records for bacterium flavobacterium johnsoniae

  1. Flavobacterium johnsoniae gldN and gldO are partially redundant genes required for gliding motility and surface localization of SprB.

    Science.gov (United States)

    Rhodes, Ryan G; Samarasam, Mudiarasan Napoleon; Shrivastava, Abhishek; van Baaren, Jessica M; Pochiraju, Soumya; Bollampalli, Sreelekha; McBride, Mark J

    2010-03-01

    Cells of the gliding bacterium Flavobacterium johnsoniae move rapidly over surfaces. Mutations in gldN cause a partial defect in gliding. A novel bacteriophage selection strategy was used to aid construction of a strain with a deletion spanning gldN and the closely related gene gldO in an otherwise wild-type F. johnsoniae UW101 background. Bacteriophage transduction was used to move a gldN mutation into F. johnsoniae UW101 to allow phenotypic comparison with the gldNO deletion mutant. Cells of the gldN mutant formed nonspreading colonies on agar but retained some ability to glide in wet mounts. In contrast, cells of the gldNO deletion mutant were completely nonmotile, indicating that cells require GldN, or the GldN-like protein GldO, to glide. Recent results suggest that Porphyromonas gingivalis PorN, which is similar in sequence to GldN, has a role in protein secretion across the outer membrane. Cells of the F. johnsoniae gldNO deletion mutant were defective in localization of the motility protein SprB to the cell surface, suggesting that GldN may be involved in secretion of components of the motility machinery. Cells of the gldNO deletion mutant were also deficient in chitin utilization and were resistant to infection by bacteriophages, phenotypes that may also be related to defects in protein secretion. PMID:20038590

  2. Phenotypic and molecular characterisation of fish-borne Flavobacterium johnsoniae-like isolates from aquaculture systems in South Africa.

    Science.gov (United States)

    Flemming, Leonard; Rawlings, Douglas; Chenia, Hafizah

    2007-01-01

    Fish infections caused by pathogenic Flavobacterium species are a major problem in the aquaculture industry worldwide, often leading to large economic losses. Thirty-two Flavobacterium spp. isolates, obtained from various diseased fish species and biofilm growth, were characterised genetically using 16S rDNA PCR restriction fragment length polymorphism (RFLP), randomly amplified polymorphic DNA (RAPD) PCR, repetitive extragenic palindromic (REP) element PCR, plasmid profiling, whole cell protein (WCP) and outer membrane protein (OMP) analyses. Although the Flavobacterium spp. isolates displayed a high degree of genetic heterogeneity when differentiated by RAPD-PCR, REP-PCR and OMP fingerprinting techniques, isolates appeared very homogeneous by plasmid profiling and WCP analysis. No specific correlation was observed between the RAPD, REP and/or OMP profiles and fish host, site of isolation, geographic location or date of isolation of the Flavobacterium spp. isolates. Experimental infection of tilapia fish revealed variable levels of virulence and pathogenicity by isolates following handling stress and could not be linked to specific molecular types. This is the first reported isolation and characterisation of Flavobacterium johnsoniae-like spp. isolated from diseased fish in Southern Africa. PMID:17113757

  3. Flavobacterium ceti sp. nov., isolated from beaked whales (Ziphius cavirostris).

    Science.gov (United States)

    Vela, A I; Fernandez, A; Sánchez-Porro, C; Sierra, E; Mendez, M; Arbelo, M; Ventosa, A; Domínguez, L; Fernández-Garayzábal, J F

    2007-11-01

    Three isolates of a Gram-negative, catalase- and oxidase-positive, rod-shaped bacterium, isolated from the lung and liver of two beaked whales, were characterized by phenotypic and molecular genetic methods. Based on cellular morphology and biochemical criteria, the isolates were tentatively assigned to the family Flavobacteriaceae, although they did not appear to correspond to any recognized species. Comparative 16S rRNA gene sequencing showed that the three new isolates shared 100% sequence similarity. The unknown bacterium was phylogenetically closely related to, but distinct from the type strains of Flavobacterium johnsoniae (93.7% sequence similarity), Flavobacterium frigidimaris (93.4%), Flavobacterium aquidurense (93.4%), Flavobacterium hibernum (93.4%) and Flavobacterium degerlachei (93.4%). The novel isolates were readily distinguished from these and other related Flavobacterium species by physiological and biochemical tests. On the basis of phenotypic and phylogenetic evidence, it is proposed that the unknown isolates from whales are classified as a novel species of the genus Flavobacterium, Flavobacterium ceti sp. nov. The type strain is 454-2T (=CECT 7184T=CCUG 52969T).

  4. Identification of a 4-Deoxy-l-erythro-5-hexoseulose Uronic Acid Reductase, FlRed, in an Alginolytic Bacterium Flavobacterium sp. Strain UMI-01

    Directory of Open Access Journals (Sweden)

    Akira Inoue

    2015-01-01

    Full Text Available In alginate-assimilating bacteria, alginate is depolymerized to unsaturated monosaccharide by the actions of endolytic and exolytic alginate lyases (EC 4.2.2.3 and EC 4.2.2.11. The monosaccharide is non-enzymatically converted to 4-deoxy-l-ery thro-5-hexoseulose uronic acid (DEH, then reduced to 2-keto-3-deoxy-d-gluconate (KDG by a specific reductase, and metabolized through the Entner–Doudoroff pathway. Recently, the NADPH-dependent reductase A1-R that belongs to short-chain dehydrogenases/reductases (SDR superfamily was identified as the DEH-reductase in Sphingomonas sp. A1. We have subsequently noticed that an SDR-like enzyme gene, flred, occurred in the genome of an alginolytic bacterium Flavobacterium sp. strain UMI-01. In the present study, we report on the deduced amino-acid sequence of flred and DEH-reducing activity of recombinant FlRed. The deduced amino-acid sequence of flred comprised 254 residues and showed 34% amino-acid identities to that of A1-R from Sphingomonas sp. A1 and 80%–88% to those of SDR-like enzymes from several alginolytic bacteria. Common sequence motifs of SDR-superfamily enzymes, e.g., the catalytic tetrad Asn-Lys-Tyr-Ser and the cofactor-binding sequence Thr-Gly-x-x-x-Gly-x-Gly in Rossmann fold, were completely conserved in FlRed. On the other hand, an Arg residue that determined the NADPH-specificity of Sphingomonas A1-R was replaced by Glu in FlRed. Thus, we investigated cofactor-preference of FlRed using a recombinant enzyme. As a result, the recombinant FlRed (recFlRed was found to show high specificity to NADH. recFlRed exhibited practically no activity toward variety of aldehyde, ketone, keto ester, keto acid and aldose substrates except for DEH. On the basis of these results, we conclude that FlRed is the NADH-dependent DEH-specific SDR of Flavobacterium sp. strain UMI-01.

  5. The Screw-Like Movement of a Gliding Bacterium Is Powered by Spiral Motion of Cell-Surface Adhesins.

    Science.gov (United States)

    Shrivastava, Abhishek; Roland, Thibault; Berg, Howard C

    2016-09-01

    Flavobacterium johnsoniae, a rod-shaped bacterium, glides over surfaces at speeds of ∼2 μm/s. The propulsion of a cell-surface adhesin, SprB, is known to enable gliding. We used cephalexin to generate elongated cells with irregular shapes and followed their displacement in three dimensions. These cells rolled about their long axes as they moved forward, following a right-handed trajectory. We coated gold nanoparticles with an SprB antibody and tracked them in three dimensions in an evanescent field where the nanoparticles appeared brighter when they were closer to the glass. The nanoparticles followed a right-handed spiral trajectory on the surface of the cell. Thus, if SprB were to adhere to the glass rather than to a nanoparticle, the cell would move forward along a right-handed trajectory, as observed, but in a direction opposite to that of the nanoparticle. PMID:27602728

  6. Gene deletion strategy to examine the involvement of the two chondroitin lyases in Flavobacterium columnare virulence.

    Science.gov (United States)

    Li, Nan; Qin, Ting; Zhang, Xiao Lin; Huang, Bei; Liu, Zhi Xin; Xie, Hai Xia; Zhang, Jin; McBride, Mark J; Nie, Pin

    2015-11-01

    Flavobacterium columnare is an important bacterial pathogen of freshwater fish that causes high mortality of infected fish and heavy economic losses in aquaculture. The pathogenesis of this bacterium is poorly understood, in part due to the lack of efficient methods for genetic manipulation. In this study, a gene deletion strategy was developed and used to determine the relationship between the production of chondroitin lyases and virulence. The F. johnsoniae ompA promoter (PompA) was fused to sacB to construct a counterselectable marker for F. columnare. F. columnare carrying PompA-sacB failed to grow on media containing 10% sucrose. A suicide vector carrying PompA-sacB was constructed, and a gene deletion strategy was developed. Using this approach, the chondroitin lyase-encoding genes, cslA and cslB, were deleted. The ΔcslA and ΔcslB mutants were both partially deficient in digestion of chondroitin sulfate A, whereas a double mutant (ΔcslA ΔcslB) was completely deficient in chondroitin lyase activity. Cells of F. columnare wild-type strain G4 and of the chondroitin lyase-deficient ΔcslA ΔcslB mutant exhibited similar levels of virulence toward grass carp in single-strain infections. Coinfections, however, revealed a competitive advantage for the wild type over the chondroitin lyase mutant. The results indicate that chondroitin lyases are not essential virulence factors of F. columnare but may contribute to the ability of the pathogen to compete and cause disease in natural infections. The gene deletion method developed in this study may be employed to investigate the virulence factors of this bacterium and may have wide application in many other members of the phylum Bacteroidetes.

  7. Parasitism enhances tilapia susceptibility to Flavobacterium columnare

    Science.gov (United States)

    Flavobacterium columnare, a Gram-negative bacterium, is the causative agent of columnaris disease. Many commercially important freshwater fish worldwide are susceptible to columnaris disease that can result in high fish mortality. Ichthyophthirius multifiliis (Ich) is a protozoan parasite in many ...

  8. Flavobacterium shanxiense sp. nov., isolated from soil.

    Science.gov (United States)

    Yang, Fan; Liu, Hong-Ming; Zhang, Rong; Chen, Ding-Bin; Wang, Xiang; Yan, Xin; Hong, Qing; Li, Shun-Peng

    2015-06-01

    Strain YF-2(T), a Gram-staining-negative, non-motile, non-spore-forming, light-yellow-pigmented bacterium, was isolated from soil samples collected in the city of Yuncheng, Shanxi province of China. Strain YF-2(T) grew over a temperature range of 25-37 °C, at pH 5.0-8.0 and with 0-5 % (w/v) NaCl. Phylogenetic analysis based on sequence of the 16S rRNA gene showed that strain YF-2(T) was closely related to strains Flavobacterium akiainvivens CIP 110358(T) and Flavobacterium hauense KCTC 32147(T) with 95.99 and 95.92 % sequence similarity, respectively. The dominant fatty acids of strain YF-2(T) were Summed Feature 3 (comprising C16:1 ω7c and/or C16:1 ω6c) (21.97 %), iso-C15:0 (18.65 %), iso-C17:0 3OH (11.41 %), C16:0 (9.92 %), and anteiso-C15:0 (6.21 %). It contained phosphatidylethanolamine and menaquinone MK-6 as major polar lipid and respiratory quinone, respectively. Strain YF-2(T) differs from other Flavobacterium species in many characteristics and represents a novel species, for which the name Flavobacterium shanxiense sp. nov. is proposed. The type strain is strain YF-2(T) (=CCTCC AB 2014079(T) = JCM 30153(T)). PMID:25726422

  9. Flavobacterium procerum sp. nov., isolated from freshwater.

    Science.gov (United States)

    Feng, Qingqing; Han, Lu; Yuan, Xin; Tan, Xu; Gao, Yuan; Lv, Jie

    2015-08-01

    A Gram-reaction-negative, strictly aerobic, yellow-pigmented, rod-shaped bacterium, designated strain T3T, was isolated from freshwater of Chishui River flowing through Maotai town, Guizhou, south-west China. Analysis of the16S rRNA gene sequence indicated that strain T3T was a member of the genus Flavobacterium and closely related to Flavobacterium resistens DSM 19382T (96.8 %). The novel strain was able to grow at 10-34 °C (optimum 28 °C), pH 6.0-11.0 (optimum pH 8.0-9.0) and with 0-2.0 % (w/v) NaCl (optimum 0 %). The major polar lipids were phosphatidylethanolamine, two unknown glycolipids, five unknown aminolipids and four unidentified lipids, and the major respiratory quinone was MK-6. The predominant fatty acids were C16  :  1ω7c and/or C16  :  1ω6c and iso-C15  :  0. The DNA G+C content of the strain was 36 mol  %. Based on these data, strain T3T represents a novel species of the genus Flavobacterium, for which the name Flavobacterium procerum sp. nov. is proposed. The type strain is T3T ( = CGMCC 1.12926T = JCM 30113T). PMID:25969476

  10. Parasitism by Ich enhanced susceptibility of tilapia to Flavobacterium columnare

    Science.gov (United States)

    In aquaculture systems, fish are commonly infected by two or more pathogens. Bacterium Flavobacterium columnare and parasite Ichthyophthirius multifiliis (Ich) are two common pathogens of cultured fish and result in heavy economic losses for aquaculture. There is no published information available ...

  11. Chemical characterization of Flavobacterium odoratum, Flavobacterium breve, and Flavobacterium-like groups IIe, IIh, and IIf.

    OpenAIRE

    Dees, S B; Moss, C W; Hollis, D G; Weaver, R E

    1986-01-01

    The cellular fatty acid, sphingolipid, and isoprenoid quinone compositions of Flavobacterium odoratum, Flavobacterium breve, and Flavobacterium-like groups IIe, IIh, and IIf were determined, using thin-layer, gas-liquid, and reverse-phase high-performance liquid chromatography. The fatty acid data showed that groups IIe, IIh, and IIf were similar to recognized Flavobacterium species by the presence of relatively large amounts of iso-branched hydroxy and nonhydroxy acids. Groups IIe and IIh we...

  12. Purification and Characterization of a Psychrophilic, Calcium-Induced, Growth-Phase-Dependent Metalloprotease from the Fish Pathogen Flavobacterium psychrophilum

    OpenAIRE

    Secades, P; Alvarez, B.; Guijarro, J. A.

    2001-01-01

    Flavobacterium psychrophilum is a fish pathogen that commonly affects salmonids. This bacterium produced an extracellular protease with an estimated molecular mass of 55 kDa. This enzyme, designated Fpp1 (F. psychrophilum protease 1), was purified to electrophoretic homogeneity from the culture supernatant by using ammonium sulfate precipitation, ion-exchange chromatography, hydrophobic chromatography, and size exclusion chromatography. On the basis of its biochemical characteristics, Fpp1 ca...

  13. Rainbow Trout Innate Immunity against Flavobacterium psychrophilum

    Science.gov (United States)

    Flavobacterium psychrophilum infection is associated with significant loss of rainbow trout production in the U.S. and other parts of the world. In 2005, a selective breeding program was initiated at the National Center for Cool and Cold Water Aquaculture to improve rainbow trout innate resistance ...

  14. In situ enhanced bioremediation of dichlorvos by a phyllosphere Flavobacterium strain

    Institute of Scientific and Technical Information of China (English)

    Jiying NING; Gang GANG; Zhihui BAI; Qing HU; Hongyan QI; Anzhou MA; Xuliang ZHUAN; Guoqiang ZHUANG

    2012-01-01

    A bacterium capable of degrading dichlorvos was isolated from the rape phyllosphere and designated YD4. The strain was identified as Flavobacterium sp., based on its phenotypic features and 16S rRNA gene sequence. Strain YD4 was able to utilize dichlorvos as the sole source of phosphorus. In situ enhanced bioremedia- tion of dichlorvos by YD4 was hereafter studied. Chlorpyrifos and phoxim could also be degraded by this strain as the sole phosphorus source. A higher degradation rate of dichlorvos was observed after spraying YD4 onto the surface of rape leaves when compared to the sterilized- YD4 and water-treated samples. The results indicated that pesticide-degrading epiphytic bacterium could become a new way for in situ phyllosphere bioremediation where the hostile niche is unsuitable for other pesticide-degrading bacteria isolated from soil and water.

  15. Production of viable cultures of Flavobacterium psychrophilum: approach and control.

    Science.gov (United States)

    Michel, C; Antonio, D; Hedrick, R P

    1999-06-01

    Although the fish pathogen Flavobacterium psychrophilum is a major source of concern in salmonid hatcheries, few studies have been conducted on its pathogenicity. Difficulties are often experienced when trying to control or quantify standard procedures for in vitro culture of the bacterium. Plate enumeration and counting chamber enumeration combined with epifluorescent microscopy with fluorescent dyes determined that no more than 25% of the bacterial cells present in the cultures were able to produce colonies on agar media. This was strongly dependent upon different medium components. Tryptone-enriched Anacker and Ordal medium proved more suitable than tryptone-yeast extract-salts with skimmed milk. Adding horse serum and trace elements in controlled proportions offered the most reproducible results. Viable but nonculturable forms were apparently not responsible for the difficulties in production of F. psychrophilum, but the cells were highly susceptible to osmotic conditions. Improvements in the media and careful handling of the bacteria in isotonic suspension media resulted in predictable production of viable bacteria and allowed an absorbance/colony-forming-units relation curve to be established.

  16. Virulence of Flavobacterium columnare genomovars in rainbow trout Oncorhynchus mykiss.

    Science.gov (United States)

    Evenhuis, Jason P; LaFrentz, Benjamin R

    2016-08-01

    Flavobacterium columnare is the causative agent of columnaris disease and is responsible for significant economic losses in aquaculture. F. columnare is a Gram-negative bacterium, and 5 genetic types or genomovars have been described based on restriction fragment length polymorphism of the 16S rRNA gene. Previous research has suggested that genomovar II isolates are more virulent than genomovar I isolates to multiple species of fish, including rainbow trout Oncorhynchus mykiss. In addition, improved genotyping methods have shown that some isolates previously classified as genomovar I, and used in challenge experiments, were in fact genomovar III. Our objective was to confirm previous results with respect to genomovar II virulence, and to determine the susceptibility of rainbow trout to other genomovars. The virulence of 8 genomovar I, 4 genomovar II, 3 genomovar II-B, and 5 genomovar III isolates originating from various sources was determined through 3 independent challenges in rainbow trout using an immersion challenge model. Mean cumulative percent mortality (CPM) of ~49% for genomovar I isolates, ~1% for genomovar II, ~5% for the II-B isolates, and ~7% for the III isolates was observed. The inability of genomovar II isolates to produce mortalities in rainbow trout was unanticipated based on previous studies, but may be due to a number of factors including rainbow trout source and water chemistry. The source of fish and/or the presence of sub-optimal environment may influence the susceptibility of rainbow trout to different F. columnare genomovars. PMID:27503917

  17. Flavobacterium psychrophilum - Experimental challenge and immune response

    DEFF Research Database (Denmark)

    Henriksen, Maya Maria Mihályi

    The disease rainbow trout fry syndrome (RTFS) is caused by the bacterial fish pathogen Flavobacterium psychrophilum. It has been the cause of great losses of rainbow trout in aquacultures both in Denmark and around the world. It was estimated that RTFS resulted in the death of 88 million fry...... the immune system of the fry is not fully developed. Theoretically, the infection pressure could be subdued by vaccinating larger fish, but no commercial vaccine is yet available. Diagnostic methods are well described and the disease is treated with antibiotics. To prevent disease outbreaks and subsequent...... and periods without disease. The main purpose and focus of the present thesis was to increase knowledge of the immune response following infection with F. psychrophilum, which may contribute to the future development of vaccines and other preventive measures. The project consisted of three main tasks: 1...

  18. Flavobacterium psychrophilum, prevention and immune response

    DEFF Research Database (Denmark)

    Henriksen, Maya Maria Mihályi; Dalsgaard, Inger

    The fish pathogen Flavobacterium psychrophilum is one of the main causes of mortality in farmed rainbow trout and other salmonid fish. The disease following infection is often called bacterial coldwater disease (BCWD) in USA or rainbow trout fry syndrome (RTFS) in Europe. An infected farm can...... expect mortality rates around 50-60% in fry and 2-10% in juvenile fish within few weeks, which causes significant economical losses worldwide. Presently no commercial vaccine exists, and fish farmers control the disease with antibiotics. The project is currently in its preliminary phase but the overall...... goal is to examine gene expression and location of transcription products in rainbow trout fry, in order to optimize vaccination or immune-stimulation. The presentation will focus on the future plans for the project, since no data have yet been obtained....

  19. Epidemiological cut-off values for Flavobacterium psychrophilum MIC data generated by a standard test protocol

    DEFF Research Database (Denmark)

    Smith, P.; Endris, R.; Kronvall, G.;

    2016-01-01

    Epidemiological cut-off values were developed for application to antibiotic susceptibility data for Flavobacterium psychrophilum generated by standard CLSI test protocols. The MIC values for ten antibiotic agents against Flavobacterium psychrophilum were determined in two laboratories. For five...

  20. Flavobacterium panacis sp. nov., isolated from rhizosphere of Panax ginseng.

    Science.gov (United States)

    Kim, Dong Hyun; Singh, Priyanka; Farh, Mohamed El-Agamy; Kim, Yeon-Ju; Nguyen, Ngoc-Lan; Lee, Hyun A; Yang, Deok-Chun

    2016-09-01

    A novel bacterial strain, designated DCY106(T), was isolated from soil collected from the rhizosphere of ginseng (Panax ginseng), in Gochang, Republic of Korea. Strain DCY106(T) is Gram-negative, yellow-pigmented, non-flagellate, motile, non-spore-forming, rod-shaped, and strictly aerobic. The strain grows optimally at 25-30 °C and pH 6.5-7.5. Phylogenetically, strain DCY106(T) is closely related to Flavobacterium arsenitoxidans KCTC 22507(T) (98.41 %), followed by Flavobacterium cutihirudini LMG 26922(T) (97.67 %), Flavobacterium nitrogenifigens LMG 28694(T) (97.59 %), Flexibacter auranticus LMG 3987(T) (97.38 %), Flavobacterium defluvi KCTC 12612(T) (97.21 %) and Flavobacterium chilense LMG 26360(T) (97.05 %). The 16S rRNA gene sequence similarities to all other Flavobacterium species were below 97 %. The DNA G+C content of strain DCY106(T) is 34.2 mol% and the DNA-DNA relatedness between strain DCY106(T) and F. cutihirudini LMG 26922(T), F. auranticus LMG 3987(T), F. defluvi KCTC 12612(T) and F. chilense LMG 26360(T) were below 40.0 %. The menaquinone of the type MK-6 was found to be the predominant respiratory quinone. The major polar lipids were identified as phosphatidylethanolamine, phosphatidylserine, two unidentified aminolipids (APL1, APL6) and one unidentified lipid L2. C15:0, iso-C15:0 and summed feature 3 (iso-C15:0 2OH/C16:1 ω7c) were identified as the major fatty acids present in DCY106(T). The results of physiological and biochemical tests allowed strain DCY106(T) to be differentiated phenotypically from other recognized species belonging to the genus Flavobacterium. Therefore, it is suggested that the newly isolated organism represents a novel species, for which the name Flavobacterium panacis sp. nov. is proposed with the type strain designated as DCY106(T) (= JCM 31468(T)= KCTC 42747(T)). PMID:27357576

  1. 21 CFR 866.3270 - Flavobacterium spp. serological reagents.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Flavobacterium spp. serological reagents. 866.3270 Section 866.3270 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... meningitis (inflammation of the membranes of the brain) and is usually attributable to contaminated...

  2. Treatment of Trichodina sp reduced load of Flavobacterium columnare and improved survival of hybrid tilapia

    Directory of Open Access Journals (Sweden)

    De-Hai Xu

    2015-11-01

    Full Text Available Bacterium Flavobacterium columnare and protozoan Trichodina spp are common pathogens of cultured fish. Studies of parasite–bacterium interaction show evidence that concurrent infections increase severity of some infectious diseases, especially bacterial diseases. The effect of parasite treatment on F. columnare infection in tilapia is currently unknown. This study evaluated whether treatment of Trichodina sp parasitized hybrid tilapia (Oreochromis niloticus × Oreochromis aureus with formalin would improve fish survival and reduce F. columnare infection in fish after F. columnare exposure. Hybrid tilapia parasitized by Trichodina sp were divided into 3 treatment groups. The first group of fish received no parasite treatment. The second group of fish were bath treated with 150 mg L−1 formalin for 1 h. The third group of fish treated twice with 150 mg L−1 formalin bath for 1 h each at 2 day intervals. All fish were then exposed to F. columnare by immersion challenge. The tilapia not treated with formalin showed significantly higher mortality (37.5% than those treated with formalin (≤16.7% after exposure to F. columnare. Fish treated twice showed lower mortality (6.37% than those treated only once (16.7%. The non-treated fish showed significantly higher load of F. columnare in gill, kidney and liver compared to those treated with formalin following exposure to F. columnare. The bacterial load of non-treated fish was 27075 genome equivalents per mg of gill tissue (GEs/mg, 12 fold higher than those treated once with formalin (2250 GEs/mg or 39 fold higher than those treated twice with formalin (699 GEs/mg after exposure to F. columnare. This study demonstrated that formalin treatment for Trichodina sp parasitism reduced bacterial infection as suggested by reduced loads of bacteria in fish tissues and subsequently decreased fish mortality.

  3. Flavobacterium nitratireducens sp. nov., an amylolytic bacterium of the family Flavobacteriaceae isolated from coastal surface seawater

    Digital Repository Service at National Institute of Oceanography (India)

    Nupur; Bhumika, V.; Srinivas, T.N.R.; AnilKumar, P.

    growth occurred at salinities up to 0-1% (w/v). Positive for ornithine decarboxylase activity and negative for catalase, oxidase, lysine decarboxylase and arginine dihydrolase actitivities. Indole and H2S production is absent. Methyl red and Voges... utilization. All strains were negative for indole production, methyl red and Voges Proskauer’s reactions, agar and Tween 20/40/60/80 hydrolysis, lysine decarboxylase, arginine dihydrolase, γ-glutamyl-transferase, β-xylosidase, β- alanine arylamidase, glycine...

  4. A bacterium capable of using phytol as its sole carbon source, isolated from algal sediment of Mud Lake, Florida.

    Science.gov (United States)

    Hoag, K B; Bradley, W H; Tousimis, A J; Price, D L

    1969-07-01

    A species of Flavobacterium that consistently attacks pure phytol and can use it as a sole source of carbon has been isolated from the blue-green algal sediment of Mud Lake, Florida. Biochemical tests demonstrate that this bacterium also readily uses various other organic compounds. This bacterium may account for the degradation products of chlorophyll and its side chain phytol, which have been found in the Mud Lake algal sediment. Phytol and its degradation products play a role in Refsum's disease, but phytol is also the most promising precursor of the isoprenoid hydrocarbons found in oil shale of the Green River Formation (Eocene) of Colorado, Utah, and Wyoming. The discovery of this species of Flavobacterium is a significant product of a protracted study of the bacteriology, phycology, zoology, and geochemistry of the algal sediment forming in Mud Lake, which is believed to be a modern analogue of the kind of algal sediment that, through geologic time, became oil shale.

  5. Adaptive response to starvation in the fish pathogen Flavobacterium columnare: cell viability and ultrastructural changes

    Directory of Open Access Journals (Sweden)

    Arias Covadonga R

    2012-11-01

    Full Text Available Abstract Background The ecology of columnaris disease, caused by Flavobacterium columnare, is poorly understood despite the economic losses that this disease inflicts on aquaculture farms worldwide. Currently, the natural reservoir for this pathogen is unknown but limited data have shown its ability to survive in water for extended periods of time. The objective of this study was to describe the ultrastructural changes that F. columnare cells undergo under starvation conditions. Four genetically distinct strains of this pathogen were monitored for 14 days in media without nutrients. Culturability and cell viability was assessed throughout the study. In addition, cell morphology and ultrastructure was analyzed using light microscopy, scanning electron microscopy, and transmission electron microscopy. Revival of starved cells under different nutrient conditions and the virulence potential of the starved cells were also investigated. Results Starvation induced unique and consistent morphological changes in all strains studied. Cells maintained their length and did not transition into a shortened, coccus shape as observed in many other Gram negative bacteria. Flavobacterium columnare cells modified their shape by morphing into coiled forms that comprised more than 80% of all the cells after 2 weeks of starvation. Coiled cells remained culturable as determined by using a dilution to extinction strategy. Statistically significant differences in cell viability were found between strains although all were able to survive in absence of nutrients for at least 14 days. In later stages of starvation, an extracellular matrix was observed covering the coiled cells. A difference in growth curves between fresh and starved cultures was evident when cultures were 3-months old but not when cultures were starved for only 1 month. Revival of starved cultures under different nutrients revealed that cells return back to their original elongated rod shape upon

  6. Draft genomes of two strains of flavobacterium isolated from lake washington sediment.

    Science.gov (United States)

    McTaggart, Tami L; Shapiro, Nicole; Woyke, Tanja; Chistoserdova, Ludmila

    2015-01-01

    We report sequencing the genomes of two new Flavobacterium strains isolated from Lake Washington sediment. From genomic contents, versatile lifestyles were predicted but not bona fide methylotrophy. With the availability of their genomic sequences, the new Flavobacterium strains present prospective models for studying microbial communities in lake sediments. PMID:25700420

  7. Complete genome sequence of the fish pathogen Flavobacterium columnare strain C#2

    Science.gov (United States)

    Flavobacterium columnare is a Gram-negative bacterial pathogen that causes columnaris disease of freshwater fish. Flavobacterium columnare strain C#2 was isolated from a diseased warm water fish and is typed as genomovar II. The genome consists of a single 3.33 Mb circular chromosome with 2,689 pred...

  8. Draft Genomes of Two Strains of Flavobacterium Isolated from Lake Washington Sediment

    OpenAIRE

    McTaggart, Tami L.; Shapiro, Nicole; Woyke, Tanja; Chistoserdova, Ludmila

    2015-01-01

    We report sequencing the genomes of two new Flavobacterium strains isolated from Lake Washington sediment. From genomic contents, versatile lifestyles were predicted but not bona fide methylotrophy. With the availability of their genomic sequences, the new Flavobacterium strains present prospective models for studying microbial communities in lake sediments.

  9. Flavobacterium psychrophilum Infections in Salmonid Broodstock and Hatchery-Propagated Stocks of the Great Lakes Basin.

    Science.gov (United States)

    Van Vliet, Danielle; Loch, Thomas P; Faisal, Mohamed

    2015-12-01

    Bacterial coldwater disease (BCWD), caused by Flavobacterium psychrophilum, threatens wild and propagated salmonids worldwide and leads to substantial economic losses. In addition to being horizontally transmitted, F. psychrophilum can be passed from infected parents to their progeny, furthering the negative impacts of this pathogen. In Michigan, both feral and captive salmonid broodstocks are the gamete sources used in fishery propagation efforts. A 5-year study was initiated to follow the prevalence of systemic F. psychrophilum infections in feral broodstocks of four species (steelhead Oncorhynchus mykiss [potadromous Rainbow Trout]; Coho Salmon O. kisutch; Chinook Salmon O. tshawytscha; and Atlantic Salmon Salmo salar) residing in three Great Lakes watersheds. Additionally, captive broodstocks of four species (Rainbow Trout, Brown Trout Salmo trutta, Lake Trout Salvelinus namaycush, and Brook Trout Salvelinus fontinalis) maintained at two facilities were assessed for the presence of F. psychrophilum. The resultant offspring from each broodstock population were sampled for F. psychrophilum infections multiple times throughout hatchery residency. Using selective flavobacterial culture and PCR confirmation, F. psychrophilum was detected in all broodstocks except the captive Lake Trout and Brook Trout. Logistic regression analysis demonstrated that among the infected feral broodstocks, Chinook Salmon from the Lake Michigan watershed had the highest prevalence of systemic F. psychrophilum infection (mean = 63.2%). Among the captive broodstocks, the Gilchrist Creek strain of Brown Trout had the highest infection prevalence (mean = 5%). Collectively, the captive broodstocks were found to have significantly lower infection prevalence than the feral broodstocks. Despite the high prevalence of systemic F. psychrophilum infections in many broodstock populations, the bacterium was rarely detected in their progeny during hatchery rearing. However, heavy losses associated

  10. Flavobacterium psychrophilum Infections in Salmonid Broodstock and Hatchery-Propagated Stocks of the Great Lakes Basin.

    Science.gov (United States)

    Van Vliet, Danielle; Loch, Thomas P; Faisal, Mohamed

    2015-12-01

    Bacterial coldwater disease (BCWD), caused by Flavobacterium psychrophilum, threatens wild and propagated salmonids worldwide and leads to substantial economic losses. In addition to being horizontally transmitted, F. psychrophilum can be passed from infected parents to their progeny, furthering the negative impacts of this pathogen. In Michigan, both feral and captive salmonid broodstocks are the gamete sources used in fishery propagation efforts. A 5-year study was initiated to follow the prevalence of systemic F. psychrophilum infections in feral broodstocks of four species (steelhead Oncorhynchus mykiss [potadromous Rainbow Trout]; Coho Salmon O. kisutch; Chinook Salmon O. tshawytscha; and Atlantic Salmon Salmo salar) residing in three Great Lakes watersheds. Additionally, captive broodstocks of four species (Rainbow Trout, Brown Trout Salmo trutta, Lake Trout Salvelinus namaycush, and Brook Trout Salvelinus fontinalis) maintained at two facilities were assessed for the presence of F. psychrophilum. The resultant offspring from each broodstock population were sampled for F. psychrophilum infections multiple times throughout hatchery residency. Using selective flavobacterial culture and PCR confirmation, F. psychrophilum was detected in all broodstocks except the captive Lake Trout and Brook Trout. Logistic regression analysis demonstrated that among the infected feral broodstocks, Chinook Salmon from the Lake Michigan watershed had the highest prevalence of systemic F. psychrophilum infection (mean = 63.2%). Among the captive broodstocks, the Gilchrist Creek strain of Brown Trout had the highest infection prevalence (mean = 5%). Collectively, the captive broodstocks were found to have significantly lower infection prevalence than the feral broodstocks. Despite the high prevalence of systemic F. psychrophilum infections in many broodstock populations, the bacterium was rarely detected in their progeny during hatchery rearing. However, heavy losses associated

  11. NCBI nr-aa BLAST: CBRC-AGAM-07-0028 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-AGAM-07-0028 ref|YP_001193977.1| hypothetical protein Fjoh_1626 [Flavobacterium john...soniae UW101] gb|ABQ04658.1| hypothetical protein Fjoh_1626 [Flavobacterium johnsoniae UW101] YP_001193977.1 5e-72 44% ...

  12. NCBI nr-aa BLAST: CBRC-ACAR-01-0498 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-ACAR-01-0498 ref|YP_001193539.1| hypothetical protein Fjoh_1188 [Flavobacterium john...soniae UW101] gb|ABQ04220.1| hypothetical protein Fjoh_1188 [Flavobacterium johnsoniae UW101] YP_001193539.1 0.055 28% ...

  13. NCBI nr-aa BLAST: CBRC-ATHA-01-0012 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-ATHA-01-0012 ref|YP_001192932.1| sodium/hydrogen exchanger [Flavobacterium john...soniae UW101] gb|ABQ03613.1| sodium/hydrogen exchanger [Flavobacterium johnsoniae UW101] YP_001192932.1 4e-17 23% ...

  14. NCBI nr-aa BLAST: CBRC-AGAM-07-0041 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-AGAM-07-0041 ref|YP_001193736.1| UbiA prenyltransferase [Flavobacterium johnso...niae UW101] gb|ABQ04417.1| UbiA prenyltransferase [Flavobacterium johnsoniae UW101] YP_001193736.1 4e-31 33% ...

  15. NCBI nr-aa BLAST: CBRC-AGAM-07-0045 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-AGAM-07-0045 ref|YP_001192547.1| heavy metal translocating P-type ATPase [Flavobacterium john...soniae UW101] gb|ABQ03228.1| heavy metal translocating P-type ATPase [Flavobacterium johnsoniae UW101] YP_001192547.1 1e-129 62% ...

  16. NCBI nr-aa BLAST: CBRC-DDIS-02-0191 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-DDIS-02-0191 ref|YP_001193285.1| Mn2+/Fe2+ transporter, NRAMP family [Flavobacterium john...soniae UW101] gb|ABQ03966.1| Mn2+/Fe2+ transporter, NRAMP family [Flavobacterium johnsoniae UW101] YP_001193285.1 9e-75 51% ...

  17. NCBI nr-aa BLAST: CBRC-TTRU-01-0993 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-TTRU-01-0993 ref|YP_001197115.1| vitamin K epoxide reductase [Flavobacterium john...soniae UW101] gb|ABQ07796.1| Vitamin K epoxide reductase [Flavobacterium johnsoniae UW101] YP_001197115.1 0.057 23% ...

  18. NCBI nr-aa BLAST: CBRC-AGAM-07-0044 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-AGAM-07-0044 ref|YP_001193285.1| Mn2+/Fe2+ transporter, NRAMP family [Flavobac...terium johnsoniae UW101] gb|ABQ03966.1| Mn2+/Fe2+ transporter, NRAMP family [Flavobacterium johnsoniae UW101] YP_001193285.1 1e-123 62% ...

  19. NCBI nr-aa BLAST: CBRC-DDIS-02-0255 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-DDIS-02-0255 ref|YP_001197147.1| Urea transporter [Flavobacterium johnsoniae U...W101] gb|ABQ07828.1| Urea transporter [Flavobacterium johnsoniae UW101] YP_001197147.1 3e-50 39% ...

  20. NCBI nr-aa BLAST: CBRC-AGAM-07-0034 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-AGAM-07-0034 ref|YP_001193612.1| major facilitator superfamily MFS_1 [Flavobac...terium johnsoniae UW101] gb|ABQ04293.1| major facilitator superfamily MFS_1 [Flavobacterium johnsoniae UW101] YP_001193612.1 3e-63 49% ...

  1. NCBI nr-aa BLAST: CBRC-MDOM-08-0106 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-MDOM-08-0106 ref|YP_001197055.1| hypothetical protein Fjoh_4737 [Flavobacteriu...m johnsoniae UW101] gb|ABQ07736.1| hypothetical protein Fjoh_4737 [Flavobacterium johnsoniae UW101] YP_001197055.1 0.24 27% ...

  2. NCBI nr-aa BLAST: CBRC-AGAM-07-0007 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-AGAM-07-0007 ref|YP_001197147.1| Urea transporter [Flavobacterium johnsoniae U...W101] gb|ABQ07828.1| Urea transporter [Flavobacterium johnsoniae UW101] YP_001197147.1 4e-69 48% ...

  3. NCBI nr-aa BLAST: CBRC-AGAM-07-0045 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-AGAM-07-0045 ref|YP_001195410.1| heavy metal translocating P-type ATPase [Flavob...acterium johnsoniae UW101] gb|ABQ06091.1| heavy metal translocating P-type ATPase [Flavobacterium johnsoniae UW101] YP_001195410.1 1e-129 64% ...

  4. NCBI nr-aa BLAST: CBRC-CREM-01-1268 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-CREM-01-1268 ref|YP_001193395.1| hypothetical protein Fjoh_1043 [Flavobacteriu...m johnsoniae UW101] gb|ABQ04076.1| hypothetical protein Fjoh_1043 [Flavobacterium johnsoniae UW101] YP_001193395.1 4e-05 24% ...

  5. NCBI nr-aa BLAST: CBRC-AGAM-07-0073 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-AGAM-07-0073 ref|YP_001195652.1| protein of unknown function DUF81 [Flavobacte...rium johnsoniae UW101] gb|ABQ06333.1| protein of unknown function DUF81 [Flavobacterium johnsoniae UW101] YP_001195652.1 4e-97 65% ...

  6. NCBI nr-aa BLAST: CBRC-AGAM-07-0040 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-AGAM-07-0040 ref|YP_001197343.1| MATE efflux family protein [Flavobacterium jo...hnsoniae UW101] gb|ABQ08024.1| MATE efflux family protein [Flavobacterium johnsoniae UW101] YP_001197343.1 6e-52 43% ...

  7. NCBI nr-aa BLAST: CBRC-ACAR-01-0780 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-ACAR-01-0780 ref|YP_001195297.1| protein of unknown function UPF0118 [Flavobac...terium johnsoniae UW101] gb|ABQ05978.1| protein of unknown function UPF0118 [Flavobacterium johnsoniae UW101] YP_001195297.1 0.13 31% ...

  8. Antimicrobial resistance patterns in Danish isolates of Flavobacterium psychrophilum

    DEFF Research Database (Denmark)

    Bruun, Morten Sichlau; Schmidt, A.S.; Madsen, Lone;

    2000-01-01

    were tested and the resulting antibiograms were used to predict the theoretical therapeutic efficacy and to evaluate if resistance had changed as a course of time. Antimicrobial agents included in this investigation were oxolinic acid (OXA), amoxicillin (AMX), potentiated sulfadiazine, oxytetracycline......The resistance pattern of Flavobacterium psychrophilum to the antimicrobial agents used in fish farming in Denmark was assessed in vitro using an agar dilution method. After identification of 387 isolates from clinical outbreaks of rainbow trout fry syndrome (RTFS) and the environment, the isolates...... (OTC) and florfenicol (FLO). We found that F. psychrophilum isolates divided in susceptible and resistant clusters reflecting the reduced efficacy in practice when using OTC and AMX. The most recent isolates were less susceptible to AMX and OXA, whereas resistance to OTC seemed stable over the last 5...

  9. Occurrence of Flavobacterium psychrophilum in fish-farming environments

    DEFF Research Database (Denmark)

    Madetoja, J.; Dalsgaard, Inger; Wiklund, T.

    2002-01-01

    Occurrence of Flavobacterium psychrophilum in fish farms and fish-farming environments was studied using agar plate cultivation,the immunoflourescence antibody technique (IFAT) and nested PCR. Characteristics of 64 F. psychrophilum isolates from rainbow trout Oncorhynchus mykiss, fish farm rearing...... water, ovarian fluid and wild fish were serotyped, ribotyped and compared biochemically. Virulence of F. psychrophilum isolates from different sources was compared by injection into rainbow trout. Additionally, the number of F. psychrophilum cells shed by naturally infected rainbow trout was determined....... F. psychrophilum was detected and isolated from skin mucus, skin lesions and internal organs of diseased rainbow trout and from fish without clinical disease. The pathogen was also present in wild perch Perca fluviatilis, roach Rutilus rutilus, and ovarian fluids of farmed rainbow trout brood fish...

  10. Flavobacterium paronense sp. nov., isolated from freshwater of an artificial vegetated island.

    Science.gov (United States)

    Joung, Yochan; Kang, Heeyoung; Kim, Haneul; Kim, Tae-Su; Han, Ji-Hye; Kim, Seung Bum; Ahn, Tae-Seok; Joh, Kiseong

    2016-01-01

    A Gram-stain-negative, motile by gliding, yellow-pigmented bacterial strain, designated KNUS1T, was isolated from Lake Paro in Korea. The phylogenetic tree based on 16S rRNA gene sequences showed that strain KNUS1T formed a distinct lineage within the genus Flavobacterium. Strain KNUS1T was closely related to Flavobacterium cheonhonense ARSA-15T (96.8 %16S rRNA gene sequence similarity), Flavobacterium pectinovorum DSM 6368T (96.3 %) and Flavobacterium dankookense ARSA-19T (96.1 %). The major fatty acids of strain KNUS1T were iso-C15 : 0 and iso-C15 : 1 G. The major polyamine was sym-homospermidine. The major polar lipids of strain KNUS1T were phosphatidylethanolamine, five unidentified aminolipids and three unidentified polar lipids. The major respiratory'quinone was menaquinone 6 (MK-6). The DNA G+C content of strain KNUS1T was 34.2 mol%. On the basis of the evidence presented in this study, strain KNUS1T represents a novel species of the genus Flavobacterium, for which the name Flavobacterium paronense sp. nov. is proposed. The type strain is KNUS1T ( = KACC 17692T = CECT 8460T). PMID:26530258

  11. Neutrophil Migration in the Activation of the Innate Immune Response to Different Flavobacterium psychrophilum Vaccines in Zebrafish (Danio rerio

    Directory of Open Access Journals (Sweden)

    Camila J. Solís

    2015-01-01

    Full Text Available Flavobacterium psychrophilum is a Gram-negative bacterium, responsible for the bacterial cold-water disease and the rainbow trout fry syndrome in freshwater salmonid fish. At present, there is only one commercial vaccine in Chile, made with two Chilean F. psychrophilum isolates and another licensed in Europe. The present study analyzed neutrophil migration, as a marker of innate immune activation, in zebrafish (Danio rerio in response to different F. psychrophilum bath vaccines, which is the first step in evaluating vaccine effectiveness and efficiency in fish. Results indicated that bacterins of the LM-02-Fp isolate were more immunogenic than those from the LM-13-Fp isolate. However, no differences were observed between the same bacteria inactivated by either formaldehyde or heat. Importantly, the same vaccine formulation without an adjuvant only triggered a mild neutrophil migration compared to the complete vaccine. Observations also found that, after a year of storage at 4°C, the activation of the innate immune system by the different vaccines was considerably decreased. Finally, new vaccine formulations prepared with heat and formaldehyde inactivated LM-02-Fp were significantly more efficient than the available commercial vaccine in regard to stimulating the innate immune system.

  12. Purification and properties of elastolytic enzyme from Flavobacterium immotum.

    Science.gov (United States)

    Ozaki, H; Shiio, I

    1975-01-01

    Elastolytic enzyme was purified and crystallized from culture fluid of Flavobacterium immotum No. 9-35. The purified enzyme was homogeneous on polyacrylamide gel electrophoresis. The molecular weight was determined by Sephadex G-100 gel filtration to be 13,000. The isoelectric point was between pH 8.3 and 8.9. The optimum pH of the enzyme was 7.2 for elastolytic activity. The purified enzyme showed not only elastolytic activity, but also non-specific proteolytic activity against various other proteins. Milk-clotting activity was also observed. The enzyme did not act on keratin, collagen, or fourteen amino acid esters, including N-benzoyl-L-alanine methyl ester, N-benzoyl-L-arginine ethyl ester, and N-acetyl-L-tyrosine ethyl ester, which were typical substrates of pancreatic elastase [EC 3.4.21.11], trypsin [EC 3.4.21.4], and chymotrypsin [EC 3.4.21.1], respectively. However, the enzyme selectively hydrolyzed elastin when both elastin and albumin were present in the reaction mixture. The enzyme was inhibited by o-phenanthroline and various heavy metals such as cadmium, lead, zinc, and mercury. Various inhibitors, such as diisopropyl phosphofluoridate, tosyl-L-lysine chloromethyl ketone, tosyl-L-phenylalanine chloromethyl ketone, trypsin inhibitor, iodoacetamide, etc., had no effect on the elastolytic activity.

  13. Immune response in rainbow trout against infection with Flavobacterium psychrophilum

    DEFF Research Database (Denmark)

    Henriksen, Maya Maria Mihályi; Kania, Per; Madsen, Lone;

    The fish pathogen Flavobacterium psychrophilum is one of the main causes of mortality in farmed rainbow trout and other salmonid fish. An infected farm can expect mortality rates around 50-60% in fry and 2-10% in juvenile fish within few weeks. Presently no commercial vaccine exists, and fish...... farmers control the disease with antibiotics. The pathogen has a limited ability to cause disease in an experimental setting without applying a stressor. A bath-model using 150mg/L H2O2 for 60 minutes as a stressor was used on 1.4g rainbow trout fry in four experimental groups: 1) no H2O2/no bath...... and 4 hours, 2 days, 5 days, 8 days and 17 days after exposure. The samples will be used for examining the gene expression in rainbow trout related to infection with F. psychrophilum and results will be presented. Furthermore, antibody production will be assessed using ELISA on serum samples. The...

  14. Isolation and characterization of a new arsenic methylating bacterium from soil

    Energy Technology Data Exchange (ETDEWEB)

    Honschopp, S. [Bremen Univ. (Germany). Abt. Mikrobiologie; Brunken, N. [Bremen Univ. (Germany). Inst. fuer Anorganische und Physikalische Chemie; Nehrkorn, A. [Bremen Univ. (Germany). Abt. Mikrobiologie; Breunig, H.J. [Bremen Univ. (Germany). Inst. fuer Anorganische und Physikalische Chemie

    1996-12-31

    An arsenic resistant and arsenic methylating bacterium belonging to the Flavobacterium-Cytophaga group was isolated from soil with an arsenic content of 1.5 ppm. The growth of the bacterium is enhanced in the presence of As compounds in concentrations up to 200 ppm in the cultural media with a stronger effect of As(V) than of As(III) compounds. As a volatile product of the methylation of both NaH{sub 2}AsO{sub 3} and NaH{sub 2}AsO{sub 4} exclusively, Me{sub 3}As was formed and detected by mass spectrometry. Quantitative aspects of the methylation were studied with GC/MS. The intracellular accumulation of arsenic in the methylating strain was compared with two non methylating strains from the same soil. (orig.)

  15. IDENTIFICATION OF A FLAVOBACTERIUM STRAIN VIRULENT AGAINT GIARDIA LAMBLIA CYSTS

    Science.gov (United States)

    We have isolated a bacterial strain capable of killing the cyst form of Giardia lamblia, from a Kentucky stream. This bacterium, designated Sun4, is a Gram negative, aerobic rod which produces a yellow pigment, but not of the flexirubin-type. Although true gliding motility has no...

  16. Cortisol directly impacts Flavobacterium columnare in vitro growth characteristics.

    Science.gov (United States)

    Declercq, Annelies Maria; Aerts, Johan; Ampe, Bart; Haesebrouck, Freddy; De Saeger, Sarah; Decostere, Annemie

    2016-01-01

    Teleost fish faced with stressful stimuli launch an endocrine stress response through activation of the hypothalamic-pituitary-interrenal axis to release glucocorticoids, in particular cortisol, into the blood. For the majority of bacterial fish pathogens, stress is considered a key factor in disease outbreaks. Based upon studies in mammals, there is considerable evidence to suggest that, besides impairing the immune system, cortisol can have a direct effect on bacterial cells. Hitherto, this intriguing field of microbial endocrinology has remained largely unexplored in aquatic diseases. The present study investigated in vitro the impact of cortisol on phenotypic traits of the fresh water fish pathogen Flavobacterium columnare. Colonies obtained from the highly virulent (HV) isolates resulted in significantly larger and more spreading colonies compared to those from the low virulent (LV) isolates. High cortisol doses added displayed a direct effect on the bacterial cells and induced a significant decrease in colony size. An additional intriguing finding was the inverse relationship between cortisol concentrations added to the broth and the spreading character of colonies retrieved, with higher cortisol doses resulting in less rhizoid to rough and even smooth colony formation (the latter only in the LV trout isolate), suggesting a dose-response effect. The loss of the rhizoid appearance of the F. columnare colonies upon administration of cortisol, and hence the loss of motility, might indicate a phenotypic change to the biofilm state. These findings form the basis for further research on the impact of glucocorticoids on other virulence factors and biofilm formation of F. columnare. PMID:27530746

  17. Treatment of Trichodina sp. reduced load of Flavobacterium colummnare and improved survival of hybrid tilapia

    Science.gov (United States)

    Parasites and bacteria are common inhabitants in water of fish farms. The effect of parasite treatment on Flavobacterium columnare infection in tilapia is currently unknown. This study evaluated whether treatment of Trichodina sp. parasitized hybrid tilapia (Oreochromis niloticus × O. aureus) would...

  18. Effect of Bacteriophages on the Growth of Flavobacterium psychrophilum and Development of Phage-Resistant Strains

    DEFF Research Database (Denmark)

    Christiansen, Rói Hammershaimb; Madsen, Lone; Dalsgaard, Inger;

    2016-01-01

    The controlling effect of single and multiple phages on the density of Flavobacterium psychrophilum at different initial multiplicity of infection (MOI) was assessed in batch cultures to explore the potential for phage-based treatment of this important fish pathogen. A high initial phage concentr...

  19. Effect of Hydrogen Peroxide on Immersion Challenge of Rainbow Trout Fry with Flavobacterium psychrophilum

    DEFF Research Database (Denmark)

    Henriksen, Maya Maria Mihályi; Madsen, Lone; Dalsgaard, Inger

    2013-01-01

    An experimental model for immersion challenge of rainbow trout fry (Oncorhynchus mykiss) with Flavobacterium psychrophilum, the causative agent of rainbow trout fry syndrome and bacterial cold water disease was established in the present study. Although injection-based infection models are reliable...

  20. Complete Genome Sequence of the Fish Pathogen Flavobacterium columnare Pf1.

    Science.gov (United States)

    Zhang, Yulei; Nie, Pin; Lin, Li

    2016-01-01

    Flavobacterium columnare is the etiologic agent of columnaris disease, a devastating fish disease prevailing in worldwide aquaculture industry. Here, we describe the complete genome of F. columnare strain Pf1, a highly virulent strain isolated from yellow catfish (Pelteobagrus fulvidraco) in China. PMID:27587818

  1. Enrichment and isolation of Flavobacterium strains with tolerance to high concentrations of cesium ion.

    Science.gov (United States)

    Kato, Souichiro; Goya, Eri; Tanaka, Michiko; Kitagawa, Wataru; Kikuchi, Yoshitomo; Asano, Kozo; Kamagata, Yoichi

    2016-01-01

    Interest in the interaction of microorganisms with cesium ions (Cs(+)) has arisen, especially in terms of their potent ability for radiocesium bioaccumulation and their important roles in biogeochemical cycling. Although high concentrations of Cs(+) display toxic effects on microorganisms, there have been only limited reports for Cs(+)-tolerant microorganisms. Here we report enrichment and isolation of Cs(+)-tolerant microorganisms from soil microbiota. Microbial community analysis revealed that bacteria within the phylum Bacteroidetes, especially Flavobacterium spp., dominated in enrichment cultures in the medium supplemented with 50 or 200 mM Cs(+), while Gammaproteobacteria was dominant in the control enrichment cultures (in the presence of 50 and 200 mM K(+) instead of Cs(+)). The dominant Flavobacterium sp. was successfully isolated from the enrichment culture and was closely related to Flavobacterium chungbukense with 99.5% identity. Growth experiments clearly demonstrated that the isolate has significantly higher tolerance to Cs(+) compared to its close relatives, suggesting the Cs(+)-tolerance is a specific trait of this strain, but not a universal trait in the genus Flavobacterium. Measurement of intracellular K(+) and Cs(+) concentrations of the Cs(+)-tolerant isolate and its close relatives suggested that the ability to maintain low intracellular Cs(+) concentration confers the tolerance against high concentrations of external Cs(+). PMID:26883718

  2. Effectiveness of copper sulfate and potassium permanganate on channel catfish infected with Flavobacterium columnare

    Science.gov (United States)

    Copper sulfate (CuSO4) and potassium permanganate (KMnO4) were evaluated for their effectiveness to curtail mortality and decrease bacterial load in fish tissues and water in channel catfish Ictalurus punctatus naturally infected with Flavobacterium columnare, the causative agent of columnaris. Fis...

  3. Development of Culture Medium for the Isolation of Flavobacterium and Chryseobacterium from Rhizosphere Soil.

    Science.gov (United States)

    Nishioka, Tomoki; Elsharkawy, Mohsen Mohamed; Suga, Haruhisa; Kageyama, Koji; Hyakumachi, Mitsuro; Shimizu, Masafumi

    2016-06-25

    An effective medium designated phosphate separately autoclaved Reasoner's 2A supplemented with cycloheximide and tobramycin (PSR2A-C/T) has been developed for the isolation of Flavobacterium and Chryseobacterium strains from the plant rhizosphere. It consists of Reasoner's 2A agar (R2A) prepared by autoclaving phosphate and agar separately and supplementing with 50 mg L(-1) cycloheximide and 1 mg L(-1) tobramycin. A comparison was made among the following nine media: PSR2A-C/T, PSR2A-C/T supplemented with NaCl, R2A agar, R2A agar supplemented with cycloheximide and tobramycin, 1/4-strength tryptic soy agar (TSA), 1/10-strength TSA, soil-extract agar, Schaedler anaerobe agar (SAA), and SAA supplemented with gramicidin, for the recovery of Flavobacterium and Chryseobacterium strains from the Welsh onion rhizosphere. Flavobacterium strains were only isolated on PSR2A-C/T, and the recovery rate of Chryseobacterium strains was higher from PSR2A-C/T than from the eight other media. In order to confirm the effectiveness of PSR2A-C/T, bacteria were isolated from onion rhizosphere soil with this medium. Flavobacterium and Chryseobacterium strains were successfully isolated from this sample at a similar rate to that from the Welsh onion rhizosphere. PMID:27098502

  4. Composition of Extracellular Polymeric Substances (EPS) produced by Flavobacterium columnare isolated from tropical fish in Brazil.

    Science.gov (United States)

    de Alexandre Sebastião, Fernanda; Pilarski, Fabiana; Lemos, Manoel Victor Franco

    2013-01-01

    Thirty nine isolates of Flavobacterium columnare from Brazilian fish farms had their carbohydrate composition of EPS evaluated by high efficiency liquid chromatography, using the phenol-sulfuric acid method of EPS. The occurrence of capsules on F. columnare cells was not directly related to biofilm formation, and the predominant monosaccharide is glucose.

  5. Dactylogyrus intermedius parasitism enhances Flavobacterium columnare invasion and alters immune-related gene expression in Carassius auratus.

    Science.gov (United States)

    Zhang, Chao; Li, Dong-liang; Chi, Cheng; Ling, Fei; Wang, Gao-xue

    2015-09-17

    The monogenean Dactylogyrus intermedius and the bacterium Flavobacterium columnare are 2 common pathogens in aquaculture. The objective of the present study was to examine the effect of prior parasitism by D. intermedius on the susceptibility of goldfish to F. columnare and to explore the potential immune mechanisms related to the parasite infection. A F. columnare challenge trial was conducted between D. intermedius-parasitized and non-parasitized goldfish. The F. columnare load in gill, kidney, spleen and liver were compared. The expression of immune-related genes (IL-1β2, TNF-α1, TGF-β, iNOS-a, C3 and Lyz) in gill and kidney of D. intermedius-only infected and uninfected control fish were evaluated. D. intermedius-parasitized goldfish exhibited higher mortality and significantly higher loads (3051 to 537,379 genome equivalents [GEs] mg(-1)) of F. columnare, which were 1.13 to 50.82-fold higher than non-parasitized fish (389 to 17,829 GEs mg(-1)). Furthermore, the immune genes IL-1β2, TNF-α1, iNOS-a and Lyz were up-regulated while the TGF-β and C3 were down-regulated in the gill and kidney of parasite-infected fish compared to the non-parasitized controls. The down-regulation TGF-β and C3 was especially noteworthy, as this might indicate the suppression of the host immune functions due to the parasitism by D. intermedius. Taken together, these data demonstrate that parasite infection can enhance bacterial invasion and presents a hypothesis, based on gene expression data, that modulation of host immune response could play a role.

  6. Diversity of Flavobacterium psychrophilum and the potential use of its phages for protection against bacterial cold water disease in salmonids

    DEFF Research Database (Denmark)

    Castillo, D.; Higuera, G.; Villa, M.;

    2012-01-01

    Flavobacterium psychrophilum causes rainbow trout fry syndrome (RTFS) and cold water disease (CWD) in salmonid aquaculture. We report characterization of F. psychrophilum strains and their bacteriophages isolated in Chilean salmonid aquaculture. Results suggest that under laboratory conditions...

  7. In vitro comparisons of the inhibitory activity of florfenicol copper sulfate and potassium permanganate towards Aeromonas hydrophila and Flavobacterium columnare

    Science.gov (United States)

    Aeromonas hydrophila and Flavobacterium columnare, the etiological agents of motile aeromonas septicemia (MAS) and columnaris disease, respectively, have been recently causing crippling moralities to the sunshine bass, Morone chrysops female X Morone saxatilis male (Percichthyidae), industry in the ...

  8. Rainbow trout fed diets with varying content of marine and plant origin; how does that influence the outcome of experimental infections of the fry with Flavobacterium psychrophilum and Yersinia ruckeri?

    DEFF Research Database (Denmark)

    Madsen, Lone; Ingerslev, Hans-Christian; Boye, Mette;

    2014-01-01

    Feed for rainbow trout aquaculture has traditionally been based on marine resources such as fish meal and fish oil. Because of a shortage of marine resources as well as the growing production of farmed fish, the feed industry has been forced to partially exchange fish meal protein with proteins...... of the fish. One major cause for losses in Danish freshwater fish farms is the fry disease rainbow trout fry syndrome (RTFS), caused by the bacterium Flavobacterium psychrophilum, and experiences of the fish farmers suggest that the diet type is an important factor for disease development. Enteric redmouth...... disease caused by Yersinia ruckeri is also an economically important disease which causes problems in rainbow trout fry as well as larger fish. Rainbow trout were fed from first-feeding with five different diets; diet A with marine fish oil (conventional fry diet), diet B (an organic version of A), diet C...

  9. Peptidoglycan from Bacillus cereus Mediates Commensalism with Rhizosphere Bacteria from the Cytophaga-Flavobacterium Group

    OpenAIRE

    Peterson, Snow Brook; Dunn, Anne K.; Klimowicz, Amy K.; Handelsman, Jo

    2006-01-01

    Previous research in our laboratory revealed that the introduction of Bacillus cereus UW85 can increase the populations of bacteria from the Cytophaga-Flavobacterium (CF) group of the Bacteroidetes phylum in the soybean rhizosphere, suggesting that these rhizosphere microorganisms have a beneficial relationship (G. S. Gilbert, J. L. Parke, M. K. Clayton, and J. Handelsman, Ecology 74:840-854, 1993). In the present study, we determined the frequency at which CF bacteria coisolated with B. cere...

  10. New host record of five Flavobacterium species associated with tropical fresh water farmed fishes from North India.

    Science.gov (United States)

    Verma, Dev Kumar; Rathore, Gaurav

    2015-01-01

    Yellow pigmented, filamentous, Gram-negative bacteria belonging to genus Flavobacterium are commonly associated with infections in stressed fish. In this study, inter-species diversity of Flavobacterium was studied in apparently healthy freshwater farmed fishes. For this, ninety one yellow pigmented bacteria were isolated from skin and gill samples (n = 38) of three farmed fish species i.e. Labeo rohita, Catla catla and Cyprinus carpio. Among them, only twelve bacterial isolates (13.18%) were identified as Flavobacterium spp. on the basis of morphological, biochemical tests, partial 16S rDNA gene sequencing and phylogenetic analysis. On the basis of 16S rDNA gene sequencing, all the 12 isolates were 97.6-100% similar to six different formally described species of genus Flavobacterium. The 16S rDNA based phylogenetic analysis grouped these strains into six different clades. Of the 12 isolates, six strains (Fl9S1-6) grouped with F. suncheonense, two strains (Fl6I2, Fl6I3) with F. indicum and the rest four strains (Fl1A1, Fl2G1, Fl3H1 and Fl10T1) clustered with F. aquaticum, F. granuli, F. hercynium and F. terrae, respectively. None of these species except, F. hercynium were previously reported from fish. All the isolated Flavobacterium species possessed the ability of adhesion and biofilm formation to colonize the external surface of healthy fish. The present study is the first record of tropical freshwater farmed fishes as hosts to five environmentally associated species of the Flavobacterium.

  11. Flavobacterium faecale sp. nov., an agarase-producing species isolated from stools of Antarctic penguins.

    Science.gov (United States)

    Kim, Jin Ho; Choi, Bo Hyun; Jo, Minho; Kim, Sun Chang; Lee, Pyung Cheon

    2014-08-01

    Taxonomic studies were performed on an agarase-producing strain, designated WV33(T), isolated from faeces of Antarctic penguins. Cells of strain WV33(T) were Gram-staining-negative, strictly aerobic, orange and rod-shaped. Strain WV33(T) displayed agarase activity and was able to utilize galactose as a sole carbon source. 16S rRNA gene sequence analysis revealed that strain WV33(T) was closely related to Flavobacterium algicola TC2(T) (98.0% similarity), F. frigidarium ATCC 700810(T) (96.9%) and F. frigoris LMG 21922(T) (96.1%). The predominant cellular fatty acids were iso-C(15 : 1) G, iso-C(15 : 0), C(15 : 0), C(16 : 0) and summed feature 3 (comprising iso-C(15 : 0) 2-OH and/or C(16 : 1)ω7c). Menaquinone 6 (MK-6) was the sole quinone identified, and the major pigment was zeaxanthin. The major polar lipid was phosphatidylethanolamine. DNA-DNA relatedness of strain WV33(T) with respect to its closest phylogenetic neighbours was 25% for F. algicola NBRC 102673(T), 23% for F. frigidarium DSM 17623(T) and 21% for F. frigoris DSM 15719(T). The DNA G+C content of strain WV33(T) was 37±0.6 mol%. Based on the phenotypic, chemotaxonomic and phylogenetic data, strain WV33(T) is concluded to represent a novel species of the genus Flavobacterium, for which the name Flavobacterium faecale sp. nov. is proposed. The type strain is WV33(T) ( = KCTC 32457(T) = CECT 8384(T)).

  12. Isolation and characterization of Flavobacterium columnare (Bernardet et al. 2002) from four tropical fish species in Brazil.

    Science.gov (United States)

    Pilarski, F; Rossini, A J; Ceccarelli, P S

    2008-05-01

    Flavobacterium columnare is the causative agent of columnaris disease in freshwater fish, implicated in skin and gill disease, often causing high mortality. The aim of this study was the isolation and characterization of Flavobacterium columnare in tropical fish in Brazil. Piracanjuba (Brycon orbignyanus), pacu (Piaractus mesopotamicus), tambaqui (Colossoma macropomum) and cascudo (Hypostomus plecostomus) were examined for external lesions showing signs of colunmaris disease such as greyish white spots, especially on the head, dorsal part and caudal fin of the fish. The sampling comprised 50 samples representing four different fish species selected for study. Samples for culture were obtained by skin and kidney scrapes with a sterile cotton swabs of columnaris disease fish and streaked onto Carlson and Pacha (1968) artificial culture medium (broth and solid) which were used for isolation. The strains in the liquid medium were Gram negative, long, filamentous, exhibited flexing movements (gliding motility), contained a large number of long slender bacteria and gathered into columns'. Strains on the agar produced yellow-pale colonies, rather small, flat that had rhizoid edges. A total of four Flavobacterium columnare were isolated: 01 Brycon orbignyanus strain, 01 Piaractus mesopotamicus strain, 01 Colossoma macropomum strain, and 01 Hypostomus plecostomus strain. Biochemical characterization, with its absorption of Congo red dye, production of flexirubin-type pigments, H2S production and reduction of nitrates proved that the isolate could be classified as Flavobacterium columnare.

  13. Intragenomic heterogeneity in the 16S rRNA genes of Flavobacterium columnare and standard protocol for genomovar assignment

    Science.gov (United States)

    Genetic variability in 16S rRNA gene sequences has been demonstrated among isolates of Flavobacterium columnare and a restriction fragment length polymorphism (RFLP) assay is available for genetic typing this important fish pathogen. Interpretation of restriction patterns can be difficult due to th...

  14. Intragenomic heterogeneity in the 16S rRNA genes of Flavobacterium columnare and relevance to genomovar assignment

    Science.gov (United States)

    Genetic variability in 16S rRNA gene sequences has been demonstrated among isolates of Flavobacterium columnare and a restriction fragment length polymorphism (RFLP) assay is available for genetic typing this important fish pathogen. Interpretation of restriction patterns can be difficult due to th...

  15. Isolation and characterization of Flavobacterium columnare (Bernardet et al. 2002) from four tropical fish species in Brazil.

    Science.gov (United States)

    Pilarski, F; Rossini, A J; Ceccarelli, P S

    2008-05-01

    Flavobacterium columnare is the causative agent of columnaris disease in freshwater fish, implicated in skin and gill disease, often causing high mortality. The aim of this study was the isolation and characterization of Flavobacterium columnare in tropical fish in Brazil. Piracanjuba (Brycon orbignyanus), pacu (Piaractus mesopotamicus), tambaqui (Colossoma macropomum) and cascudo (Hypostomus plecostomus) were examined for external lesions showing signs of colunmaris disease such as greyish white spots, especially on the head, dorsal part and caudal fin of the fish. The sampling comprised 50 samples representing four different fish species selected for study. Samples for culture were obtained by skin and kidney scrapes with a sterile cotton swabs of columnaris disease fish and streaked onto Carlson and Pacha (1968) artificial culture medium (broth and solid) which were used for isolation. The strains in the liquid medium were Gram negative, long, filamentous, exhibited flexing movements (gliding motility), contained a large number of long slender bacteria and gathered into columns'. Strains on the agar produced yellow-pale colonies, rather small, flat that had rhizoid edges. A total of four Flavobacterium columnare were isolated: 01 Brycon orbignyanus strain, 01 Piaractus mesopotamicus strain, 01 Colossoma macropomum strain, and 01 Hypostomus plecostomus strain. Biochemical characterization, with its absorption of Congo red dye, production of flexirubin-type pigments, H2S production and reduction of nitrates proved that the isolate could be classified as Flavobacterium columnare. PMID:18660972

  16. Evaluation of potassium permanganate against an experimental subacute infection of Flavobacterium columnare in channel catfish, Icatlurus punctatus

    Science.gov (United States)

    The efficacy of potassium permanganate (KMnO4) as a prophylactic and therapeutic treatment for subacute infection of Flavobacterium columnare was demonstrated in experimentally infected channel catfish, Ictalurus punctatus. Catfish experimentally infected with F. columnare to mimic a subacute infec...

  17. Comparative effects of copper sulfate or potassium permanganate on channel catfish concurrently infected with Flavobacterium columnare and Ichthyobodo necator

    Science.gov (United States)

    An opportunistic study was conducted to determine the effects of two chemical therapeutants on channel catfish (CCF) Ictalurus punctatus concurrently infected Flavobacterium columnare and Ichthyobodo necator. Copper sulfate (CuSO4) and potassium permanganate (KMnO4) were investigated for their abil...

  18. In vitro and in vivo evaluation of potassium permanganate treatment efficacy for the control of acute experimental infection of flavobacterium columnare in channel catfish

    Science.gov (United States)

    An experimental trial was performed to evaluate the efficacy of potassium permanganate against an acute and systemic experimental infection of Flavobacterium columnare in channel catfish, Ictalurus punctatus. The infection was produced by waterborne exposure to the bacteria after mechanical cutaneo...

  19. Comparative Genome Analysis Provides Insights into the Pathogenicity of Flavobacterium psychrophilum

    DEFF Research Database (Denmark)

    Castillo, Daniel; Christiansen, Rói Hammershaimb; Dalsgaard, Inger;

    2016-01-01

    only matched one sequence in the database, the temperate bacteriophage 6H. Genomic Islands (GIs) were identified in F. psychrophilum isolates 950106-1/1 and CSF 259-93, associated with toxins and antibiotic resistance. Finally, phenotypic characterization revealed a high degree of similarity among......Flavobacterium psychrophilum is a fish pathogen in salmonid aquaculture worldwide that causes cold water disease (CWD) and rainbow trout fry syndrome (RTFS). Comparative genome analyses of 11 F. psychrophilum isolates representing temporally and geographically distant populations were used....... psychrophilum could hold at least 3373 genes, while the core genome contained 1743 genes. On average, 67 new genes were detected for every new genome added to the analysis, indicating that F. psychrophilum possesses an open pan genome. The putative virulence factors were equally distributed among isolates...

  20. Lactococcus lactis - a diploid bacterium

    DEFF Research Database (Denmark)

    Michelsen, Ole; Hansen, Flemming G.; Jensen, Peter Ruhdal

    In contrast to higher eukaryotes, bacteria are haploid, i.e. they store their genetic information in a single chromosome, which is then duplicated during the cell cycle. If the growth rate is sufficiently low, the bacterium is born with only a single copy of the chromosome, which gets duplicated...... before the bacterium divides. Fast-growing bacteria have overlapping rounds of replication, and can contain DNA corresponding to more than four genome equivalents. However, the terminus region of the chromosome is still present in just one copy after division, and is not duplicated until right before...... the next division. Thus, the regions of the chromosome that are the last to be replicated are haploid even in fast-growing bacteria. In contrast to this general rule for bacteria, we found that Lactococcus lactis, a bacterium which has been exploited for thousands of years for the production of fermented...

  1. Single Bacterium Detection Using Sers

    Science.gov (United States)

    Gonchukov, S. A.; Baikova, T. V.; Alushin, M. V.; Svistunova, T. S.; Minaeva, S. A.; Ionin, A. A.; Kudryashov, S. I.; Saraeva, I. N.; Zayarny, D. A.

    2016-02-01

    This work is devoted to the study of a single Staphylococcus aureus bacterium detection using surface-enhanced Raman spectroscopy (SERS) and resonant Raman spectroscopy (RS). It was shown that SERS allows increasing sensitivity of predominantly low frequency lines connected with the vibrations of Amide, Proteins and DNA. At the same time the lines of carotenoids inherent to this kind of bacterium are well-detected due to the resonance Raman scattering mechanism. The reproducibility and stability of Raman spectra strongly depend on the characteristics of nanostructured substrate, and molecular structure and size of the tested biological object.

  2. Bacteriophage Resistance Mechanisms in the Fish Pathogen Flavobacterium psychrophilum: Linking Genomic Mutations to Changes in Bacterial Virulence Factors

    DEFF Research Database (Denmark)

    Castillo, Daniel; Christiansen, Rói Hammershaimb; Dalsgaard, Inger;

    2015-01-01

    Flavobacterium psychrophilum is an important fish pathogen in salmonid aquaculture worldwide. Due to increased antibiotic resistance, pathogen control using bacteriophages has been explored as a possible alternative treatment. However, the effective use of bacteriophages in pathogen control...... resistance and the genetic modifications were supported by direct measurements of bacteriophage adsorption rates, biofilm formation, and secretion of extracellular enzymes, which were all impaired in the resistant strains, probably due to superficial structural changes. The clustered regularly interspaced...

  3. Legionella pneumophila persists within biofilms formed by Klebsiella pneumoniae, Flavobacterium sp., and Pseudomonas fluorescens under dynamic flow conditions.

    Directory of Open Access Journals (Sweden)

    Catherine R Stewart

    Full Text Available Legionella pneumophila, the agent of Legionnaires' disease pneumonia, is transmitted to humans following the inhalation of contaminated water droplets. In aquatic systems, L. pneumophila survives much of time within multi-organismal biofilms. Therefore, we examined the ability of L. pneumophila (clinical isolate 130 b to persist within biofilms formed by various types of aquatic bacteria, using a bioreactor with flow, steel surfaces, and low-nutrient conditions. L. pneumophila was able to intercalate into and persist within a biofilm formed by Klebsiella pneumoniae, Flavobacterium sp. or Pseudomonas fluorescens. The levels of L. pneumophila within these biofilms were as much as 4 × 10(4 CFU per cm(2 of steel coupon and lasted for at least 12 days. These data document that K. pneumoniae, Flavobacterium sp., and P. fluorescens can promote the presence of L. pneumophila in dynamic biofilms. In contrast to these results, L. pneumophila 130 b did not persist within a biofilm formed by Pseudomonas aeruginosa, confirming that some bacteria are permissive for Legionella colonization whereas others are antagonistic. In addition to colonizing certain mono-species biofilms, L. pneumophila 130 b persisted within a two-species biofilm formed by K. pneumoniae and Flavobacterium sp. Interestingly, the legionellae were also able to colonize a two-species biofilm formed by K. pneumoniae and P. aeruginosa, demonstrating that a species that is permissive for L. pneumophila can override the inhibitory effect(s of a non-permissive species.

  4. Morphological and genetic characteristics of Flavobacterium columnare isolates: correlations with virulence in fish.

    Science.gov (United States)

    Thomas-Jinu, S; Goodwin, A E

    2004-01-01

    Variability in pathogenicity of Flavobacterium columnare makes disease treatment difficult because there is currently no way to easily recognize those strains that warrant aggressive treatments. In order to identify suitable virulence markers, 17 isolates of F. columnare were cultured from six different fish species. The DNA from all isolates was analysed using random amplified polymorphic DNA (RAPD). Bootstrap analysis of the RAPD data produced a tree with three major groups supported by bootstrap scores of 80-100%. Virulence of the isolates was determined by bath exposure of channel catfish, Ictaluruspunctatus (Rafinesque), and golden shiners, Notemigonus crysoleucas (Mitchill), to broth cultures of F. columnare. In channel catfish, 13 of 17 isolates produced 100% mortality within 48 h post-exposure. All isolates of cyprinid fish origin clustered in a single RAPD group. At least two of the four isolates that were not virulent in channel catfish were of cyprinid fish origin. There was a wide variation in cell morphology between isolates with lengths of cells or cell chains ranging from 3 to 11 microm, even under identical culture conditions. Most of the shorter or single cell isolates fell into a single RAPD group. No clear association was identified between virulence and any other characteristic, including RAPD group. PMID:14986937

  5. Transcriptional responses of resistant and susceptible fish clones to the bacterial pathogen Flavobacterium psychrophilum.

    Directory of Open Access Journals (Sweden)

    Christelle Langevin

    Full Text Available Flavobacterium psychrophilum is a bacterial species that represents one of the most important pathogens for aquaculture worldwide, especially for salmonids. To gain insights into the genetic basis of the natural resistance to F. psychrophilum, we selected homozygous clones of rainbow trout with contrasted susceptibility to the infection. We compared the transcriptional response to the bacteria in the pronephros of a susceptible and a resistant line by micro-array analysis five days after infection. While the basal transcriptome of healthy fish was significantly different in the resistant and susceptible lines, the transcriptome modifications induced by the bacteria involved essentially the same genes and pathways. The response to F. psychrophilum involved antimicrobial peptides, complement, and a number of enzymes and chemokines. The matrix metalloproteases mmp9 and mmp13 were among the most highly induced genes in both genetic backgrounds. Key genes of both pro- and anti-inflammatory response such as IL1 and IL10, were up-regulated with a greater magnitude in susceptible animals where the bacterial load was also much higher. While higher resistance to F. psychrophilum does not seem to be based on extensive differences in the orientation of the immune response, several genes including complement C3 showed stronger induction in the resistant fish. They may be important for the variation of susceptibility to the infection.

  6. Plasmid control of 6-aminohexanoic acid cyclic dimer degradation enzymes of Flavobacterium sp. KI72.

    Science.gov (United States)

    Negoro, S; Shinagawa, H; Nakata, A; Kinoshita, S; Hatozaki, T; Okada, H

    1980-07-01

    Flavobacterium sp. K172, which is able to grow on 6-aminohexanoic acid cyclic dimer as the sole source of carbon and nitrogen, and plasmid control of the responsible enzymes, 6-aminohexanoic acid cyclic dimer hydrolase and 6-aminohexanoic acid linear oligomer hydrolase, were studied. The wild strain of K172 harbors three kinds of plasmid, pOAD1 (26.2 megadaltons), pOAD2 (28.8 megadaltons), and pOAD3 (37.2 megadaltons). The wild strain K172 was readily cured of its ability to grow on the cyclic dimer by mitomycin C, and the cyclic dimer hydrolase could not be detected either as catalytic activity or by antibody precipitation. No reversion of the cured strains was detected. pOAD2 was not detected in every cured strain tested but was restored in a transformant. The transformant recovered both of the enzyme activities, and the cyclic dimer hydrolase of the transformant was immunologically identical with that of the wild strain. All of the strains tested, including the wild, cured, and transformant ones, possessed identical pOAD3 irrespective of the metabolizing activity. Some of the cured strains possessed pOAD1 identical with the wild strain, but the others harbored plasmids with partially altered structures which were likely to be derived from pOAD1 by genetic rearrangements such as deletion, insertion, or substitution. These results suggested that the genes of the enzymes were borne on pOAD2.

  7. High-quality draft genome sequence of Flavobacterium suncheonense GH29-5T (DSM 17707T) isolated from greenhouse soil in South Korea, and emended description of Flavobacterium suncheonense GH29-5T

    OpenAIRE

    Tashkandy, Nisreen; Sabban, Sari; Fakieh, Mohammad; Meier-Kolthoff, Jan P; Huang, Sixing; Tindall, Brian J.; Rohde, Manfred; Baeshen, Mohammed N; Baeshen, Nabih A.; Lapidus, Alla; Copeland, Alex; Pillay, Manoj; Reddy, T. B. K.; Huntemann, Marcel; Pati, Amrita

    2016-01-01

    Flavobacterium suncheonense is a member of the family Flavobacteriaceae in the phylum Bacteroidetes. Strain GH29-5T (DSM 17707T) was isolated from greenhouse soil in Suncheon, South Korea. F. suncheonense GH29-5T is part of the G enomic E ncyclopedia of B acteria and A rchaea project. The 2,880,663 bp long draft genome consists of 54 scaffolds with 2739 protein-coding genes and 82 RNA genes. The genome of strain GH29-5T has 117 genes encoding peptidases but a small number of genes encoding ca...

  8. Radiological examination of the spinal column in farmed rainbow trout Oncorhynchus mykiss (Walbaum): experiments with Flavobacterium psychrophilum and oxytetracycline

    DEFF Research Database (Denmark)

    Madsen, Lone; Arnbjerg, J.; Dalsgaard, Inger

    2001-01-01

    Flavobacterium psychrophilum and oxytetracycline have both been associated with spinal deformities in salmonids. Experiments were carried out to investigate whether infection with F, psychrophilum or medication with oxytetracycline (OTC) at the fry stage would result in an increased occurrence of...... infected fish. OTC treatments of up to 200 mg of OTC(kgfish)(-1) day(-1) for 10 days and repeated three times did not result in increased spinal deformities relative to untreated control groups; therefore, medication of rainbow trout with oxytetracycline did not cause deformities of the spinal column under...

  9. Effect of Bacteriophages on the Growth of Flavobacterium psychrophilum and Development of Phage-Resistant Strains.

    Science.gov (United States)

    Christiansen, Rói Hammershaimb; Madsen, Lone; Dalsgaard, Inger; Castillo, Daniel; Kalatzis, Panos G; Middelboe, Mathias

    2016-05-01

    The controlling effect of single and multiple phages on the density of Flavobacterium psychrophilum at different initial multiplicity of infection (MOI) was assessed in batch cultures to explore the potential for phage-based treatment of this important fish pathogen. A high initial phage concentration (MOI = 0.3-4) was crucial for efficient viral lysis, resulting in a 10(4)-10(5)-fold reduction of phage-sensitive cells (both single phages and phage cocktails), which was maintained throughout the incubation (>10 days). Following cell lysis, regrowth of phage-resistant strains was examined and resistant strains were isolated for further characterization. The application of a mathematical model allowed simulation of phage-host interactions and resistance development, confirming indications from strain isolations that phage-sensitive strains dominated the regrowing population (>99.8%) at low MOI and phage-resistant strains (>87.8%) dominated at high MOI. A cross-infectivity test covering 68 isolated strains and 22 phages resulted in 23 different host susceptibility patterns, with 20 of the isolates being resistant to all the applied phages. Eleven isolated strains with different susceptibility patterns had lower growth rates (0.093 to 0.31 h(-1)) than the host strain (0.33 h(-1)), while 10 of 14 examined strains had lost the ability to take up specific substrates as shown by BIOLOG profiles. Despite increased selection for phage resistance at high MOI, the results emphasize that high initial MOI is essential for fast and effective control of F. psychrophilum infection and suggest that the small populations of resistant clones had reduced competitive abilities relative to the sensitive ancestral strain.

  10. Comparative Genome Analysis Provides Insights into the Pathogenicity of Flavobacterium psychrophilum

    Science.gov (United States)

    Castillo, Daniel; Christiansen, Rói Hammershaimb; Dalsgaard, Inger; Madsen, Lone; Espejo, Romilio

    2016-01-01

    Flavobacterium psychrophilum is a fish pathogen in salmonid aquaculture worldwide that causes cold water disease (CWD) and rainbow trout fry syndrome (RTFS). Comparative genome analyses of 11 F. psychrophilum isolates representing temporally and geographically distant populations were used to describe the F. psychrophilum pan-genome and to examine virulence factors, prophages, CRISPR arrays, and genomic islands present in the genomes. Analysis of the genomic DNA sequences were complemented with selected phenotypic characteristics of the strains. The pan genome analysis showed that F. psychrophilum could hold at least 3373 genes, while the core genome contained 1743 genes. On average, 67 new genes were detected for every new genome added to the analysis, indicating that F. psychrophilum possesses an open pan genome. The putative virulence factors were equally distributed among isolates, independent of geographic location, year of isolation and source of isolates. Only one prophage-related sequence was found which corresponded to the previously described prophage 6H, and appeared in 5 out of 11 isolates. CRISPR array analysis revealed two different loci with dissimilar spacer content, which only matched one sequence in the database, the temperate bacteriophage 6H. Genomic Islands (GIs) were identified in F. psychrophilum isolates 950106-1/1 and CSF 259–93, associated with toxins and antibiotic resistance. Finally, phenotypic characterization revealed a high degree of similarity among the strains with respect to biofilm formation and secretion of extracellular enzymes. Global scale dispersion of virulence factors in the genomes and the abilities for biofilm formation, hemolytic activity and secretion of extracellular enzymes among the strains suggested that F. psychrophilum isolates have a similar mode of action on adhesion, colonization and destruction of fish tissues across large spatial and temporal scales of occurrence. Overall, the genomic characterization and

  11. Detection and Quantification of Flavobacterium psychrophilum-Specific Bacteriophages In Vivo in Rainbow Trout upon Oral Administration: Implications for Disease Control in Aquaculture

    DEFF Research Database (Denmark)

    Christiansen, Rói Hammershaimb; Dalsgaard, Inger; Middelboe, Mathias;

    2014-01-01

    The use of bacteriophages in the treatment and prevention of infections by the fish pathogen Flavobacterium psychrophilum has attracted increased attention in recent years. It has been shown recently that phage delivery via the parenteral route resulted in immediate distribution of phages...

  12. Assessment of Aquaflor (c), copper sulfate and potassium permanganate for control of Aeromonas hydrophila and Flavobacterium columnare infection in sunshine bass, Morone chrysops female x Morone saxatilis male

    Science.gov (United States)

    Two experiments were conducted to assess different therapeutants against a mixed infection of Aeromonas hydrophila and Flavobacterium columnare in sunshine bass (SB) (Morone chrysops female x Morone saxatilis male). Experiment 1 assessed the efficacy of copper sulfate (CuSO4), florfenicol-medicated...

  13. Evaluation of the therapeutic effect of potassium permanganate at early stages of an experimental acute infection of Flavobacterium columnare in channel catfish (Ictalurus punctatus)

    Science.gov (United States)

    The efficacy of potassium permanganate (KMnO4) against early stages of an experimental acute infection of Flavobacterium columnare in channel catfish (Ictalurus punctatus) was evaluated. Fish were experimentally challenged, by waterborne exposure for 2 h to F. columnare after cutaneous abrasion, an...

  14. Proinflammatory cytokine and cytokine receptor gene expression kinetics following challenge with Flavobacterium psychrophilum in resistant and susceptible lines of rainbow trout (Oncorhynchus mykiss)

    Science.gov (United States)

    Flavobacterium psychrophilum (Fp) is the causative agent of bacterial cold water disease (BCWD) which causes appreciable economic losses in rainbow trout aquaculture. We previously reported development of a genetic line, designated ARS-Fp-R that exhibits higher survival relative to a susceptible lin...

  15. Isolation and characterisation of flavobacteria from wild and cultured freshwater fish species in Hungary.

    Science.gov (United States)

    Varga, Zsuzsanna; Sellyei, Boglárka; Paulus, Petra; Papp, Melitta; Molnár, Kálmán; Székely, Csaba

    2016-03-01

    The objective of this study was to survey the incidence of Flavobacterium columnare in wild and cultured freshwater fish species in Hungary. This bacterium usually causes disease in waters of more than 25 °C temperature. However, with the introduction of intensive fish farming systems, infected fish exposed to stress develop disease signs also at lower temperatures; in addition, the temperature of natural waters rises to the critical level due to global warming. Twenty-five isolates from wild and cultured freshwater fishes were identified as F. columnare by specific PCR, although both the fragment lengths and the results of PCRRFLP genotyping with BsuRI (HaeIII) and RsaI restriction enzymes raised doubts regarding this species classification. Sequencing of the 16S ribosomal RNA gene revealed that 23 isolates belonged to the species F. johnsoniae and two represented Chryseobacterium spp. The isolates were found to have high-level multidrug resistance: all were resistant to ampicillin and polymyxin B, the 23 F. johnsoniae strains to cotrimoxazole, 88% of them to gentamicin, and 72% to chloramphenicol. The majority of the 25 isolates were sensitive to erythromycin (88%), furazolidone (76%), and florfenicol (68%). PMID:26919138

  16. 柱状黄杆菌乙酰辅酶A合成酶基因及其上游调控序列分析%Acetyl-coenzyme A synthetase gene and its upstream promoter in the bacterial pathogen Flavobacterium columnare

    Institute of Scientific and Technical Information of China (English)

    张金; 邹红; 姚卫建; 聂品

    2011-01-01

    Flavobacterium columnare, the etiological agent of columnaris disease, is one of the most important bacterial pathogens of freshwater fish in the world. However, suitable genetic manipulation of this bacterium which has been challenging and producing genetic mutations in this bacterium has not been reported. Therefore, isolation of an effective promoter in F. Columnare may provide tools for the development of a genetic manipulation system in the bacterium. In this study, the acetyl-coenzyme A synthetase gene (acs) and flanking sequences were analyzed to determine promoter function. The acs gene is 2 323 bp long, encoding a protein of 635 amino acids. A TAAAA motif was identified as the conserved sequence for ribosome binding site (RBS) and TATTTTCG and TTG were determined to be -7 and -33 promoter motifs, upstream of the acs start codon. When a plasmid was constructed containing the acs upstream regulation sequence (Pacs) fused upstream of the chloramphenicol ace-tyltransferase (cat) gene and was introduced into F. Columnare G4 strain, the host cells gained chloramphenicol (Cm) resistance. The transcriptional start position (TSP) of acs and cat was both determined to be T locating 46 bp upstream of the start codon. Deletion analysis of the promoter showed that at least 164 bp nucleotides upstream of the start codon were required for promoter activity and for the expression of CAT to sufficiently confer the resistance in F. Columnare. Nucleotide analysis and alignment of the putative RBS for 32 protein-coding genes in F. Columnare G4 revealed the conserved RBS consensus, TAAAA, in Flavobacterium located 10 bp upstream of start codon of acs. The current study described the first successful construction of a plasmid that was able to express cloned genes in F. Columnare, which will allow further studies of the important columnaris disease in fish.%柱状黄杆菌(Flavobacterium columnare)是世界范围内危害淡水鱼类的柱形病的病原.目前对该病原菌

  17. Variable Number of Tandem Repeats (VNTR) analysis of Flavobacterium psychrophilum from salmonids in Chile and Norway

    DEFF Research Database (Denmark)

    Apablaza, Patricia; Brevik, Oyvind J.; Mjos, Svein;

    2015-01-01

    isolates of this bacterium could play an important role in the development of good management strategies. The aim of this study was to identify genetic markers for discrimination between isolates. A selection of eight VNTRs from 53 F. psychrophilum isolates from Norway, Chile, Denmark and Scotland were...... compared to those from Norway, which suggests a more homogenous reservoir in Norway. Transgenerational transmission of F. psychrophilum from other countries, exporting salmon embryos to Chile, may explain the differences in diversity. The same transmission mechanisms could also explain the wide...

  18. 31P nuclear magnetic resonance studies of effects of some chlorophenols on Escherichia coli and a pentachlorophenol-degrading bacterium.

    OpenAIRE

    Steiert, J G; Thoma, W J; Ugurbil, K; Crawford, R L

    1988-01-01

    A Flavobacterium sp. that mineralizes pentachlorophenol degrades some, but not all, of the other chlorinated phenols. Whole-cell 31P nuclear magnetic resonance was used to compare and observe transmembrane pH gradients and nucleotide pools in the Flavobacterium sp. and Escherichia coli after pentachlorophenol and 3,4,5-trichlorophenol were added to the cell suspensions. The data suggest that those chlorinated phenols which are not degraded by the Flavobacterium sp. may be resistant to degrada...

  19. Laboratory challenges with the bacterial pathogen, Flavobacterium columnare and infection of juvenile lost river suckers (Deltistes luxatus) during their exposure to sublethal ammonia concentrations at pH 9.5

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Three Flavobacterium columnare isolates which had been obtained from dying adult suckers at Upper Klamath Lake during a fish kill in August, 1996 and stored by...

  20. Efficiency of oxytetracycline treatment in rainbow trout experimentally infected with Flavobacterium psychrophilum strains having different in vitro antibiotic susceptibilities

    DEFF Research Database (Denmark)

    Bruun, Morten Sichlau; Madsen, Lone; Dalsgaard, Inger

    2003-01-01

    100 mg oxytetracycline/kg fish for 10 days. The three F. psychrophilum strains had different antimicrobial susceptibilities and successful treatment was only obtained in the trial using a strain with a MICOTC of 0.25 mug/ml. No effect of treatment was seen in the group infected with a strain having......The medication effect of oxytetracycline on groups of rainbow trout fry experimentally infected with three strains of Flavobacterium psychrophilum was investigated. The infection model was based on intraperitoneal injection of the pathogen and treatment was done using medicated feed resulting in...... MICOTC of 8.0 mug/ml and only little effect was seen when the strain MICOTC was 4.0 mug/ml. This shows that it is valid to predict the treatment efficiency of OTC from in vitro data facing an outbreak of rainbow trout fry syndrome. The importance of doing susceptibility testing is emphasized, and as...

  1. Real-time kinetics of electrogenic Na+ transport by rhodopsin from the marine flavobacterium Dokdonia sp. PRO95

    OpenAIRE

    Bogachev, Alexander V.; Bertsova, Yulia V.; Verkhovskaya, Marina L.; Mamedov, Mahir D.; Skulachev, Vladimir P.

    2016-01-01

    Discovery of the light-driven sodium-motive pump Na+-rhodopsin (NaR) has initiated studies of the molecular mechanism of this novel membrane-linked energy transducer. In this paper, we investigated the photocycle of NaR from the marine flavobacterium Dokdonia sp. PRO95 and identified electrogenic and Na+-dependent steps of this cycle. We found that the NaR photocycle is composed of at least four steps: NaR 519 + hv → K 585 → (L 450↔M 495) → O 585 → NaR 519. The third step is the only step tha...

  2. Feifantangia zhejiangensis gen. nov., sp. nov., a marine bacterium isolated from seawater of the East China Sea.

    Science.gov (United States)

    Zheng, Gang; Chen, Zuo-Guo; Jiang, Ri-Jin; Yang, Zhi-Jian

    2015-12-01

    A marine bacterium, NMD7(T), was isolated from seawater of the East China Sea. The cells were found to be aerobic, Gram-stain negative, non-motile rods. Growth of strain NMD7(T) could be observed in the medium without Na(+). Flexirubin-type pigments were observed to be produced. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain NMD7(T) is an authentic member of the Cytophaga-Flavobacterium-Bacteroides phylum, forming a monophyletic clade as retrieved in neighbor-joining, maximum-likelihood and maximum-parsimony phylogenetic trees, and is closely related to Formosa spongicola A2(T) (96.0 %). The predominant respiratory quinone was determined to be MK-6. Major cellular fatty acids were identified as iso-C15:0, iso-C15:1 G and iso-C17:0 3-OH. The main polar lipids were found to consist of phosphatidylethanolamine, one aminophospholipid, three aminolipids and five unidentified lipids. Based on phenotypic, chemotaxonomic and phylogenetic characteristics, it is proposed that strain NMD7(T) be classified as representing a new genus, Feifantangia gen. nov. and a new species, Feifantangia zhejiangensis sp. nov. The type strain is NMD7(T) (=KCTC 42445T =MCCC 1K00458T). PMID:26410371

  3. Hematology and productive performance of nile tilapia (Oreochromis niloticus naturally infected with Flavobacterium columnare

    Directory of Open Access Journals (Sweden)

    F. A Sebastião

    2011-03-01

    Full Text Available Columnaris disease is one of the main causes of mortality in tilapia rearing and is responsible for large economic losses worldwide. Hematology is a tool that makes it possible to study organisms' physiological responses to pathogens. It may assist in making diagnoses and prognoses on diseases in fish populations. The hematological variables of nile tilapia were studied in specimens with a clinical diagnosis of columnaris disease and in specimens that were disease-free. The total erythrocyte count, hemoglobin rate, hematocrit percentage, mean corpuscular hemoglobin (MCH, mean corpuscular hemoglobin concentration (MCHC, mean corpuscular volume (MCV, organic defense blood cell percentages (leukocytes and thrombocytes and hepatosomatic and splenosomatic index were determined. The results showed that there were changes in the erythrocytic series and in organic defense blood cells, in the fish infected with the bacterium, with reductions in erythrocytic variables and significant increases in the numbers of circulating lymphocytes and neutrophils.

  4. Influence of organic diets and probiotics on an experimental Flavobacterium psychrophilum infection in rainbow trout fry

    DEFF Research Database (Denmark)

    Madsen, Lone; Ingerslev, Hans-Christian; Boye, Mette;

    2012-01-01

    following exposure to pathogenic microorganisms. The aim of the Danish project OPTIFISH is to optimize growth and survival for organic cultured rainbow trout. OPTIFISH investigates how organic vs. non-organic diet types as well as diets with or without probiotics affect the intestine, the intestinal...... of fry to pathogens, e.g. F .psychrophilum. In the current experiment four diet types were tested on fry, a conventional type (Inicio®, BioMar A/S) with and without probiotics, as well as an organic type with and without probiotic. Bactocell® (Lallemand) was used as the probiotic. Studies were done...... been fed diets that were organic or conventional nor if the feed had been added probiotic. No significance in mortalities was seen between the diet groups. The bacteriological examinations showed that the bacterium had entered the fish, as it was found in inner organs in one fourth of the sampled fish...

  5. Draft Genome Sequence of Flavobacterium sp. Strain TAB 87, Able To Inhibit the Growth of Cystic Fibrosis Bacterial Pathogens Belonging to the Burkholderia cepacia Complex.

    Science.gov (United States)

    Presta, Luana; Inzucchi, Ilaria; Bosi, Emanuele; Fondi, Marco; Perrin, Elena; Miceli, Elisangela; Tutino, Maria Luisa; Lo Giudice, Angelina; de Pascale, Donatella; Fani, Renato

    2016-01-01

    We report here the draft genome sequence of the Flavobacterium sp. TAB 87 strain, isolated from Antarctic seawater during a summer campaign near the French Antarctic station Dumont d'Urville (60°40'S, 40°01'E). It will allow for comparative genomics and the fulfillment of both fundamental and application-oriented investigations. It allowed the recognition of genes associated with the production of bioactive compounds and antibiotic resistance. PMID:27198032

  6. Photocatalytic inactivation of Flavobacterium and E. coli in water by a continuous stirred tank reactor (CSTR) fed with suspended/immobilised TiO2 medium.

    Science.gov (United States)

    Cohen-Yaniv, Vered; Narkis, Nava; Armon, Robert

    2008-01-01

    A photocatalytic continuous stirred tank reactor (CSTR) was built at laboratory scale to inactivate two environmental bacteria strains (Flavobacterium and E. coli) in tap water. Several parameters were found to impact reactor efficiency. Bacterial initial concentration is an important factor in inactivation rate. After 30 minutes of irradiation at 10(8)-10(9) CFU mL(-1) starting concentration, a >5 log reduction was achieved while at 10(4)-10(6) CFU mL(-1) only a 2 log reduction was observed. Water hardness and pH have an important influence on the photocatalytic inactivation process. Soft water, with low Ca(+2) and Mg(+2) at low pH approximately 5.3 resulted in increased inactivation of Flavobacterium reaching >6 orders of magnitude reduction. E. coli and Flavobacterium at pH 5 were inactivated by 3 logs more as compared to pH 7 under similar conditions. pH below TiO2 isoelectric point (approximately 5.6) supports better contact between bacteria and anatase particles resulting in superior inactivation. TiO2 powder suspension was compared with immobilised powder in sol-gel coated glass beads in order to exclude the need for particles separation from the treated water. TiO2 suspension was more effective by 3 orders of magnitude when compared to coated glass beads. An interesting observation was found between the two bacterial strains based on their hydrophobicity/hydrophilicity balance. The more hydrophobic Flavobacterium compared to E. coli was inactivated photocatalytically by >3 logs more then E. coli in the first 30 minutes of irradiation interval. The results indicate the importance of the parameters involved in the contact between TiO2 particles and microorganisms that govern the successful inactivation rate in CSTR.

  7. IDENTIFICATION OF THE BACTERIUM TOMATO STEM CANKER

    Directory of Open Access Journals (Sweden)

    Goner A. Shaker

    2014-01-01

    Full Text Available Diseased tomato samples were collected from green house was evaluated for isolation, pathogenicity and biochemical tests. The symptoms of the infected tomato plants were as sudden wilting after curled on leaves and necrotic streak regions developed at the crown and base of the stem and the cavities deepen and expand up and down, brown discoloration and necrosis occurring on xylem and phloem vasculer. All of ages of tomato plant were susceptible to bacteria when the weather condition favorable and immediately, seen collapse symptom on tomato plant at once fail and die. The bacterium was isolated from diseased plant in all regions on nutrient Agar; a yellow bacterium was isolated from infected tomato plant in green houses and fields in Abu-Ghraib, Rashiedia and Qanat Al-Geiaysh nurseries in Baghdad provinces of Iraq. The bacterium was found gram positive, rod-shaped, non-motile and capable an aerobic growth and based on the morphological and biochemical characteristics revealed that this bacterium belongs to: Clavibacter michiganensis subsp. michiganensis. (smith pathogenicity and hypersensitivity of the bacterium Cmm showed the disease index were 18.33, 6.66, 16.66, 5, 0% for tomato seedlings were inoculated treatments as the wounding roots, without wounding roots, crown of the stem, petiole and control respectively.

  8. Microflora of urogenital tract in pregnancy with asymptomatic bacterium

    International Nuclear Information System (INIS)

    The article contains results of research interrelationship from colonization of vagina and urinary tract diseases. E.coli one of the main factors in development asymptomatic bacterium. Presented high effects of penicillin medicaments and nitrofurans in treatment of asymptomatic bacterium

  9. Zymomonas mobilis: a bacterium for ethanol production

    Energy Technology Data Exchange (ETDEWEB)

    Baratti, J.C.; Bu' Lock, J.D.

    1986-01-01

    Zymomonas mobilis is a facultative anaerobic gram negative bacterium first isolated in tropical countries from alcoholic beverages like the African palm wine, the Mexican pulque and also as a contaminant of cider (cider sickness) or beer in the European countries. It is one of the few facultative anaerobic bacteria degrading glucose by the Entner-Doudoroff pathway usually found in strictly aerobic microorganisms. Some work was devoted to this bacterium in the 50s and 60s and was reviewed by Swings and De Ley in their classical paper published in 1977. During the 70s there was very little work on the bacterium until 1979 and the first report by the Australian group of P.L. Rogers on the great potentialities of Z. mobilis for ethanol production. At that time the petroleum crisis had led the developed countries to search for alternative fuel from renewable resources. The Australian group clearly demonstrated the advantages of the bacterium compared to the yeasts traditionally used for the alcoholic fermentation. As a result, there was a considerable burst in the Zymomonas literature which started from nearly zero in the late 70s to attain 70 papers published in the field in 1984. In this article, papers published from 1982 to 1986 are reviewed.

  10. Optimization Medium Composition for Vitamin K2 by Flavobacterium sp. using Response Surface Methodology and Addition ofArachis hypogaea

    Directory of Open Access Journals (Sweden)

    Mu Tan

    2016-01-01

    Full Text Available ABSTRACT The purpose of this research was to enhance the production of vitamin K2 by fermentation optimization and Arachis hypogaea supplementation in Flavobacterium sp. mutant SP-L-01. Optimized culture condition were as follows: 6-days shake-flask culture at 37oC with initial pH value 7.0 ± 0.2, shaking speed in 120 r/min and medium volume of 30 mL with 2% inoculums. After optimization of fermentation medium by response surface methodology (RSM, optimized medium were maltose 23.8 g/l, glucose 9.69 g/l, beef extract 15 g/l, K2HPO4 4.5 g/l,NaCl 3.0 g/l and MgSO4·7H2O 0.3 g/l. Production of vitamin K2 after optimization reached to 10.97 mg/l, which is 79.25% higher than that before optimization (6.12 mg/l. 3 mg/mL of arachis hypogaea was added into the medium at 72 h of shake-flake cultivation, which improved the production of menaquinone-4 (MK4 up to 371% and menaquinone-6 (MK6 up to 149% higher than those of the original medium. D-(+-catechin, one of the components of arachis hypogaea, was added alone into the medium, which also improved the vitamin K2 synthesis.

  11. Improved husbandry to control an outbreak of rainbow trout fry syndrome caused by infection with Flavobacterium psychrophilum

    Science.gov (United States)

    Bebak, J.A.; Welch, T.J.; Starliper, C.E.; Baya, A.M.; Garner, M.M.

    2007-01-01

    Case Description - A cohort of 35,200, 13-week-old, female rainbow trout at a fish farm was evaluated because of a 2-week history of anorexia and lethargy and a mortality rate of approximately 100 fish/d. Clinical Findings - Affected fish were lethargic and thin and had disequilibrium, bilateral exophthalmia, pale red gills and kidneys, red-tinged coelomic fluid, and pale brown livers. Some fish were differentially pigmented bilaterally. The presumptive diagnosis was bacterial or viral septicemia. The definitive diagnosis was rainbow trout fry syndrome caused by infection with Flavobacterium psychrophilum. Treatment and Outcome - A strategy for controlling the outbreak based on reducing pathogen numbers in affected tanks and reducing pathogen spread among tanks was developed. The option of treating with antimicrobial-medicated feed was discussed with the farmer, but was declined. After changes were made, mortality rate declined quickly, with no more deaths within 10 days after the initial farm visit. Clinical Relevance - Bacterial coldwater disease is the most common manifestation of infection with F psychrophilum in fingerling and adult rainbow trout. However, the organism can also cause rainbow trout fry syndrome. This condition should be included on a list of differential diagnoses for septicemia in hatchery-reared rainbow trout fry.

  12. Computer-aided vaccine designing approach against fish pathogens Edwardsiella tarda and Flavobacterium columnare using bioinformatics softwares.

    Science.gov (United States)

    Mahendran, Radha; Jeyabaskar, Suganya; Sitharaman, Gayathri; Michael, Rajamani Dinakaran; Paul, Agnal Vincent

    2016-01-01

    Edwardsiella tarda and Flavobacterium columnare are two important intracellular pathogenic bacteria that cause the infectious diseases edwardsiellosis and columnaris in wild and cultured fish. Prediction of major histocompatibility complex (MHC) binding is an important issue in T-cell epitope prediction. In a healthy immune system, the T-cells must recognize epitopes and induce the immune response. In this study, T-cell epitopes were predicted by using in silico immunoinformatics approach with the help of bioinformatics tools that are less expensive and are not time consuming. Such identification of binding interaction between peptides and MHC alleles aids in the discovery of new peptide vaccines. We have reported the potential peptides chosen from the outer membrane proteins (OMPs) of E. tarda and F. columnare, which interact well with MHC class I alleles. OMPs from E. tarda and F. columnare were selected and analyzed based on their antigenic and immunogenic properties. The OMPs of the genes TolC and FCOL_04620, respectively, from E. tarda and F. columnare were taken for study. Finally, two epitopes from the OMP of E. tarda exhibited excellent protein-peptide interaction when docked with MHC class I alleles. Five epitopes from the OMP of F. columnare had good protein-peptide interaction when docked with MHC class I alleles. Further in vitro studies can aid in the development of potential peptide vaccines using the predicted peptides. PMID:27284239

  13. Intragenomic heterogeneity in the 16S rRNA genes of Flavobacterium columnare and standard protocol for genomovar assignment.

    Science.gov (United States)

    LaFrentz, B R; Waldbieser, G C; Welch, T J; Shoemaker, C A

    2014-07-01

    Genetic variability in 16S rRNA gene sequences has been demonstrated among isolates of Flavobacterium columnare, and a restriction fragment length polymorphism (RFLP) assay is available for genetic typing of this important fish pathogen. Interpretation of restriction patterns can be difficult due to the lack of a formal description of the expected number and sizes of DNA fragments generated for each of the described genomovars. In this study, partial 16S rRNA gene sequences (ca. 1250-bp fragment) from isolates representing each described genomovar and isolates generating unique restriction patterns were cloned and sequenced. The results demonstrated that some isolates contained up to three different 16S rRNA genes whose sequences generate different RFLP patterns due to intragenomic heterogeneity within HaeIII restriction sites. The occurrence of HaeIII restriction sites within the portion of the 16S rRNA gene used for typing the F. columnare isolates and intragenomic heterogeneity within these sites explained the restriction patterns observed following RFLP analyses. This research provides a standard protocol for typing isolates of F. columnare by RFLP and a formal description of the expected restriction patterns for the previously described genomovars I, II, II-B and III. Additionally, we describe a new genomovar, I/II.

  14. Lack of association between Flavobacterium columnare genomovar and virulence in hybrid tilapia Oreochromis niloticus (L.)×Oreochromis aureus (Steindachner).

    Science.gov (United States)

    Shoemaker, C A; LaFrentz, B R

    2015-05-01

    Columnaris disease can be problematic in tilapia (Oreochromis spp.) production. An understanding of the pathogenesis and virulence of Flavobacterium columnare is needed to develop prevention strategies. The objective of this study was to determine the virulence of genetically defined isolates of F. columnare in sex-reversed hybrid tilapia, Oreochromis niloticus (L.)×O. aureus (Steindachner). A series of immersion challenge trials were performed using isolates of the five established genomovars of F. columnare: I, II, II-B, III and I/II. The mean per cent mortality of fish challenged with genomovar I, II and III isolates ranged from 0 to 100, 3.3-78 and 3.3-75%, respectively. The mean per cent mortality of fish challenged with genomovar II-B ranged from 35 to 96.7%, and the only genomovar I/II isolate tested caused no mortality. Contrary to previous work in other fish species, there did not appear to be an association between F. columnare genomovar and virulence in tilapia. The challenge model used resulted in acute mortality. An alternative challenge model was tested by cohabitating healthy fish with dead fish infected with F. columnare. This method resulted in rapid appearance of clinical signs and mortality, suggesting the potential for F. columnare to increase in virulence upon growth on/in a fish host. PMID:24909885

  15. Genomic makeup of the marine flavobacterium Nonlabens (Donghaeana) dokdonensis and identification of a novel class of rhodopsins.

    Science.gov (United States)

    Kwon, Soon-Kyeong; Kim, Byung Kwon; Song, Ju Yeon; Kwak, Min-Jung; Lee, Choong Hoon; Yoon, Jung-Hoon; Oh, Tae Kwang; Kim, Jihyun F

    2013-01-01

    Rhodopsin-containing marine microbes such as those in the class Flavobacteriia play a pivotal role in the biogeochemical cycle of the euphotic zone (Fuhrman JA, Schwalbach MS, Stingl U. 2008. Proteorhodopsins: an array of physiological roles? Nat Rev Microbiol. 6:488-494). Deciphering the genome information of flavobacteria and accessing the diversity and ecological impact of microbial rhodopsins are important in understanding and preserving the global ecosystems. The genome sequence of the orange-pigmented marine flavobacterium Nonlabens dokdonensis (basonym: Donghaeana dokdonensis) DSW-6 was determined. As a marine photoheterotroph, DSW-6 has written in its genome physiological features that allow survival in the oligotrophic environments. The sequence analysis also uncovered a gene encoding an unexpected type of microbial rhodopsin containing a unique motif in addition to a proteorhodopsin gene and a number of photolyase or cryptochrome genes. Homologs of the novel rhodopsin gene were found in other flavobacteria, alphaproteobacteria, a species of Cytophagia, a deinococcus, and even a eukaryote diatom. They all contain the characteristic NQ motif and form a phylogenetically distinct group. Expression analysis of this rhodopsin gene in DSW-6 indicated that it is induced at high NaCl concentrations, as well as in the presence of light and the absence of nutrients. Genomic and metagenomic surveys demonstrate the diversity of the NQ rhodopsins in nature and the prevalent occurrence of the encoding genes among microbial communities inhabiting hypersaline niches, suggesting its involvement in sodium metabolism and the sodium-adapted lifestyle.

  16. A new species of the genus Flavobacterium%黄杆菌属中的一个新种

    Institute of Scientific and Technical Information of China (English)

    孙谧; 张云波; 洪义国; 王跃军; 邱秀宝; 董美娜; 桑玉泉; 王春波

    2000-01-01

    由海产贝类中分离到一菌株YS-9412-130,为革兰氏阴性短杆菌、末端圆、有鞭毛、不能滑行运动、大小为0.4~0.7μm×1.0~1.5μm,裂殖生殖,不生成芽孢,胞内无多-β-羟基丁酸颗粒。菌落光滑,黄色、半透明,边缘完整。其色素无荧光,含类胡萝卜素,其正己烷提取液经光谱测定最大吸收峰为450nm。该菌生长的温度范围为0~25℃,最适为18~22℃,最高25℃(在25℃生长极弱或几乎不生长)。此菌株于pH7.0~9.0能生长,最适pH为7.5,耐6%NaCl,80μg/m1的链霉素或80μg/ml的氨卞青霉素。YS-9412-130菌株为好气菌,严格的有氧呼吸代谢,过氧化氢酶、氧化酶阳性和磷酸酶阳性,利用多种糖、水解淀粉但不分解纤维素、琼脂和几丁质。水解干酪素、胨化石蕊牛奶最后变碱。液化明胶试验阴性,还原硝酸盐;不产H2S和吲哚;MR和V.P.试验阴性;YS-9412-130菌株DNA中G+C含量为32.2mol%。该菌株的特征符合黄杆菌属的特征,但与此属中的其他种比较又有显著的差别,因此将其定为黄杆菌属一新种,命名为黄海黄杆菌(Flavobacterium yellowsea sp.nov)。%The strain YS-9412-130 is isolated from marine shells. The cells of strain are short rods with rounded ends, measuring 0.4~0.7μm by 1.0~1.5μm, gram-positive, flagellated, not gliding movement, reproduction by schizogenesis. Endospores not formed. Intracellular granules of poly-β-hydroxybutyrate are absent. Colonies of strain YS-9412-130 are yellow colour, translucent and smooth with entire edges. The pigments are non-fluorescent, and include carotenoids. The maximum absorption peak of the pigments in n-hexane is 450nm.The temperature range for growth is 0 to 25℃, minimum, 5℃, optimum, 18 to 22℃; maximum, 25℃(very week growth or almost no growth ); the pH range for growth is 7.0~9.0, optimum growth occurred at pH7.5. This strain may be tolerant of 6%Na

  17. Protection against Flavobacterium psychrophilum infection (cold water disease) in Ayu fish (Plecoglossus altivelis) by oral administration of humus extract.

    Science.gov (United States)

    NAKAGAWA, Jun; IWASAKI, Tadashi; KODAMA, Hiroshi

    2009-11-01

    Humic substances are formed during the decomposition of organic matter in humus, and are found in many natural environments in which organic materials and microorganisms have been present. In the present study, oral administration of humus extract to ayu fish (Plecoglossus altivelis) induced effective protection against experimental Flavobacterium psychrophilum infection (cold water disease). Mortality of fish and development of skin lesions, such as erosion and hemorrhages on the skin, gill cover or mouth, were significantly suppressed in fish treated with 10%, 5% or 1% humus extract adsorbed on dry pellets. Although F. psychrophilum was not re-isolated from gills and erosion lesions of the skin of dead fish, bacterial gyrB DNA could be amplified in these specimens from dead fish and surviving control fish using the polymerase chain reaction. The protective effect of the extract was not the results of direct killing of bacteria or antibiotic activity of the extract since no obvious reduction in the bacterial number was observed at 5 times to 5,000 times dilution of the humus extract having pH 5.45 to 7.40. These results clearly show that treating fish with humus extract is effective in preventing cold water disease.

  18. Novel Waddlia Intracellular Bacterium in Artibeus intermedius Fruit Bats, Mexico.

    Science.gov (United States)

    Pierlé, Sebastián Aguilar; Morales, Cirani Obregón; Martínez, Leonardo Perea; Ceballos, Nidia Aréchiga; Rivero, Juan José Pérez; Díaz, Osvaldo López; Brayton, Kelly A; Setién, Alvaro Aguilar

    2015-12-01

    An intracellular bacterium was isolated from fruit bats (Artibeus intermedius) in Cocoyoc, Mexico. The bacterium caused severe lesions in the lungs and spleens of bats and intracytoplasmic vacuoles in cell cultures. Sequence analyses showed it is related to Waddlia spp. (order Chlamydiales). We propose to call this bacterium Waddlia cocoyoc.

  19. Dicty_cDB: Contig-U03062-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 1.2 11 ( CP000685 ) Flavobacterium johnsoniae UW101, complete genome. 36 1.3 17 ( FG292300 ) 1108457713646 New World... Screwworm Larvae 9387 EST... 36 1.3 2 ( FG293205 ) 1108770666478 New World Screwworm Larvae 9387 ES

  20. Lysine and novel hydroxylysine lipids in soil bacteria: amino acid membrane lipid response to temperature and pH in

    NARCIS (Netherlands)

    Moore, E.K.; Hopmans, E.C.; Rijpstra, W.I.C.; Sánchez-Andrea, I.; Villanueva, L.; Wienk, H.; Schoutsen, F; Stams, A.J.M.; Sinninghe Damsté, J.S.

    2015-01-01

    Microbial decomposition of organic matter is an essential process in the global carbon cycle. The soil bacteria Pseudopedobacter saltans and Flavobacterium johnsoniae are both able to degrade complex organic molecules, but it is not fully known how their membrane structures are adapted to their envi

  1. Flavobacterium psychrophilum y su patología en alevines de Onchorhynchus mykiss del centro piscícola El Ingenio, Huancayo

    OpenAIRE

    Jorge León; Rita Ávalos; Milagros Ponce

    2008-01-01

    En el presente trabajo se reporta la presencia de Flavobacterium psychrophilum, como agente causante de la patología “enfermedad bacteriana del agua fría” en alevines de Onchorhynchus mykiss “trucha arco iris” del Centro Piscícola El Ingenio, Junín (3250 m de altitud). La lesión macroscópica externa más frecuente fue la ulceración profunda de la región dorsal del pez acompañado de un ennegrecimiento localizado de la piel. Internamente se observó una marcada esplenomegalia, palidez del hígado,...

  2. Computer-aided vaccine designing approach against fish pathogens Edwardsiella tarda and Flavobacterium columnare using bioinformatics softwares

    Directory of Open Access Journals (Sweden)

    Mahendran R

    2016-05-01

    Full Text Available Radha Mahendran,1 Suganya Jeyabaskar,1 Gayathri Sitharaman,1 Rajamani Dinakaran Michael,2 Agnal Vincent Paul1 1Department of Bioinformatics, 2Centre for Fish Immunology, School of Life Sciences, Vels University, Pallavaram, Chennai, Tamil Nadu, India Abstract: Edwardsiella tarda and Flavobacterium columnare are two important intracellular pathogenic bacteria that cause the infectious diseases edwardsiellosis and columnaris in wild and cultured fish. Prediction of major histocompatibility complex (MHC binding is an important issue in T-cell epitope prediction. In a healthy immune system, the T-cells must recognize epitopes and induce the immune response. In this study, T-cell epitopes were predicted by using in silico immunoinformatics approach with the help of bioinformatics tools that are less expensive and are not time consuming. Such identification of binding interaction between peptides and MHC alleles aids in the discovery of new peptide vaccines. We have reported the potential peptides chosen from the outer membrane proteins (OMPs of E. tarda and F. columnare, which interact well with MHC class I alleles. OMPs from E. tarda and F. columnare were selected and analyzed based on their antigenic and immunogenic properties. The OMPs of the genes TolC and FCOL_04620, respectively, from E. tarda and F. columnare were taken for study. Finally, two epitopes from the OMP of E. tarda exhibited excellent protein–peptide interaction when docked with MHC class I alleles. Five epitopes from the OMP of F. columnare had good protein–peptide interaction when docked with MHC class I alleles. Further in vitro studies can aid in the development of potential peptide vaccines using the predicted peptides. Keywords: E. tarda, F. columnare, edwardsiellosis, columnaris, T-cell epitopes, MHC class I, peptide vaccine, outer membrane proteins 

  3. Profilings of MicroRNAs in the Liver of Common Carp (Cyprinus carpio Infected with Flavobacterium columnare

    Directory of Open Access Journals (Sweden)

    Lijuan Zhao

    2016-04-01

    Full Text Available MicroRNAs (miRNAs play important roles in regulation of many biological processes in eukaryotes, including pathogen infection and host interactions. Flavobacterium columnare (FC infection can cause great economic loss of common carp (Cyprinus carpio which is one of the most important cultured fish in the world. However, miRNAs in response to FC infection in common carp has not been characterized. To identify specific miRNAs involved in common carp infected with FC, we performed microRNA sequencing using livers of common carp infected with and without FC. A total of 698 miRNAs were identified, including 142 which were identified and deposited in the miRbase database (Available online: http://www.mirbase.org/ and 556 had only predicted miRNAs. Among the deposited miRNAs, eight miRNAs were first identified in common carp. Thirty of the 698 miRNAs were differentially expressed miRNAs (DIE-miRNAs between the FC infected and control samples. From the DIE-miRNAs, seven were selected randomly and their expression profiles were confirmed to be consistent with the microRNA sequencing results using RT-PCR and qRT-PCR. In addition, a total of 27,363 target genes of the 30 DIE-miRNAs were predicted. The target genes were enriched in five Kyoto Encyclopedia of Genes and Genomes (KEGG pathways, including focal adhesion, extracellular matrix (ECM-receptor interaction, erythroblastic leukemia viral oncogene homolog (ErbB signaling pathway, regulation of actin cytoskeleton, and adherent junction. The miRNA expression profile of the liver of common carp infected with FC will pave the way for the development of effective strategies to fight against FC infection.

  4. Immunogenicity and protective role of antigenic regions from five outer membrane proteins of Flavobacterium columnare in grass carp Ctenopharyngodon idella

    Science.gov (United States)

    Luo, Zhang; Liu, Zhixin; Fu, Jianping; Zhang, Qiusheng; Huang, Bei; Nie, Pin

    2016-02-01

    Flavobacterium columnare causes columnaris disease in freshwater fish. In the present study, the antigenic regions of five outer membrane proteins (OMPs), including zinc metalloprotease, prolyl oligopeptidase, thermolysin, collagenase and chondroitin AC lyase, were bioinformatically analyzed, fused together, and then expressed as a recombinant fusion protein in Escherichia coli. The expressed protein of 95.6 kDa, as estimated by 10% sodium dodecyl sulfate-polyacrylamide gel electrophoresis, was consistent with the molecular weight deduced from the amino acid sequence. The purified recombinant protein was used to vaccinate the grass carp, Ctenopharyngodon idella. Following vaccination of the fish their IgM antibody levels were examined, as was the expression of IgM, IgD and IgZ immunoglobulin genes and other genes such as MHC Iα and MHC IIβ, which are also involved in adaptive immunity. Interleukin genes (IL), including IL-1β, IL-8 and IL-10, and type I and type II interferon (IFN) genes were also examined. At 3 and 4 weeks post-vaccination (wpv), significant increases in IgM antibody levels were observed in the fish vaccinated with the recombinant fusion protein, and an increase in the expression levels of IgM, IgD and IgZ genes was also detected following the vaccinations, thus indicating that an adaptive immune response was induced by the vaccinations. Early increases in the expression levels of IL and IFN genes were also observed in the vaccinated fish. At four wpv, the fish were challenged with F. columnare, and the vaccinated fish showed a good level of protection against this pathogen, with 39% relative percent survival (RPS) compared with the control group. It can be concluded, therefore, that the five OMPs, in the form of a recombinant fusion protein vaccine, induced an immune response in fish and protection against F. columnare.

  5. Isolation of a Bacterium Strain Degraded Agar

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    One in 58 strains of bacteria isolated from the compost showed clear colonies after a few days of growth on the plates containing medium made of only agar and water.Water suspension contained only agar (2 and 8g·L -1 ) with two controls (normal saline,LB medium) was inoculated with the bacterium BR5-1 to see whether there was an increasement of the alive bacteria concentration after 48 h of the growth.The results showed that there was a significant rising of the alive bacteria concentration in the agar susp...

  6. Swimming Efficiency of Bacterium Escherichia Coli

    CERN Document Server

    Chattopadhyay, S; Wu, X L; Yeung, C; Chattopadhyay, Suddhashil; Moldovan, Radu; Yeung, Chuck

    2005-01-01

    We use in vivo measurements of swimming bacteria in an optical trap to determine fundamental properties of bacterial propulsion. In particular, we determine the propulsion matrix, which relates the angular velocity of the flagellum to the torques and forces propelling the bacterium. From the propulsion matrix dynamical properties such as forces, torques, swimming speed and power can be obtained from measurements of the angular velocity of the motor. We find significant heterogeneities among different individuals even though all bacteria started from a single colony. The propulsive efficiency, defined as the ratio of the propulsive power output to the rotary power input provided by the motors, is found to be 0.2%.

  7. Efficacy of florfenicol, copper sulfate and potassium permanganate in controlling a natural infection of Aeromonas hydrophila and Flavobacterium columnare in sunshine bass, Morone chrysops female x Morone saxatilis male

    Science.gov (United States)

    Sunshine bass (Morone chrysops female ' Morone saxatilis male) naturally infected with Aeromonas hydrophila and Flavobacterium columnare were randomly assigned to six treatments: 1) two treatments of waterborne exposures to copper sulfate (CuSO4), at 2.1 and at 4.2 mg/L (approximately one and two pe...

  8. Biodegradation of heavy oils by halophilic bacterium

    Institute of Scientific and Technical Information of China (English)

    Ruixia Hao; Anhuai Lu

    2009-01-01

    A halophilic bacterial strain TM-1 was isolated from the reservoir of the Shengli oil field in East China. Strain TM-1, which was found to be able to degrade crude oils, is a gram-positive non-motile bacterium with a coccus shape that can grow at temperatures of up to 58 ℃ and in 18% NaCl solution. Depending on the culture conditions, the organism may occur in tetrads. In addition, strain TM-1 pro-duced acid from glucose without gas formation and was catalase-negative. Furthermore, strain TM-I was found to be a facultative aer-obe capable of growth under anaerobic conditions. Moreover, it produced butylated hydroxytoluene, 1,2-benzenedicarboxylic acid-bis ester and dibutyl phthalate and could use different organic substrates. Laboratory studies indicated that strain TM-1 affected different heavy oils by degrading various components and by changing the chemical properties of the oils. In addition, growth of the bacterium in heavy oils resulted in the loss of aromatic hydrocarbons, resins and asphaltenes, and enrichment with light hydrocarbons and an overall redistribution of these hydrocarbons.

  9. Diffusion of magnetotactic bacterium in rotating magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Cebers, A., E-mail: aceb@tesla.sal.l [Department of Physics, University of Latvia, Zellu 8, Ri-bar ga, LV-1002 (Latvia)

    2011-02-15

    Swimming trajectory of a magnetotactic bacterium in a rotating magnetic field is a circle. Random reversals of the direction of the bacterium motion induces a random walk of the curvature center of the trajectory. In assumption of the distribution of the switching events according to the Poisson process the diffusion coefficient is calculated in dependence on the frequency of the rotating field and the characteristic time between the switching events. It is confirmed by the numerical simulation of the random walk of the bacterium in the rotating magnetic field. - Research highlights: Random switching of the flagella leads to diffusion of a bacterium in the field. Mean square displacement of the curvature center is proportional to time. Diffusion coefficient depends on the period of a rotating field. At zero frequency diffusion coefficient is the same as for a tumbling bacterium.

  10. Fluctuation-Enhanced Sensing of Bacterium Odors

    CERN Document Server

    Chang, Hung-Chih; King, Maria D; Kwan, Chiman

    2009-01-01

    The goal of this paper is to explore the possibility to detect and identify bacteria by sensing their odor via fluctuation-enhanced sensing with commercial Taguchi sensors. The fluctuations of the electrical resistance during exposure to different bacterial odors, Escherichia coli and anthrax-surrogate Bacillus subtilis, have been measured and analyzed. In the present study, the simplest method, the measurement and analysis of power density spectra was used. The sensors were run in the normal heated and the sampling-and-hold working modes, respectively. The results indicate that Taguchi sensors used in these fluctuation-enhanced modes are effective tools of bacterium detection and identification even when they are utilizing only the power density spectrum of the stochastic sensor signal.

  11. The chemical formula of a magnetotactic bacterium.

    Science.gov (United States)

    Naresh, Mohit; Das, Sayoni; Mishra, Prashant; Mittal, Aditya

    2012-05-01

    Elucidation of the chemical logic of life is one of the grand challenges in biology, and essential to the progress of the upcoming field of synthetic biology. Treatment of microbial cells explicitly as a "chemical" species in controlled reaction (growth) environments has allowed fascinating discoveries of elemental formulae of a few species that have guided the modern views on compositions of a living cell. Application of mass and energy balances on living cells has proved to be useful in modeling of bioengineering systems, particularly in deriving optimized media compositions for growing microorganisms to maximize yields of desired bio-derived products by regulating intra-cellular metabolic networks. In this work, application of elemental mass balance during growth of Magnetospirillum gryphiswaldense in bioreactors has resulted in the discovery of the chemical formula of the magnetotactic bacterium. By developing a stoichiometric equation characterizing the formation of a magnetotactic bacterial cell, coupled with rigorous experimental measurements and robust calculations, we report the elemental formula of M. gryphiswaldense cell as CH(2.06)O(0.13)N(0.28)Fe(1.74×10(-3)). Remarkably, we find that iron metabolism during growth of this magnetotactic bacterium is much more correlated individually with carbon and nitrogen, compared to carbon and nitrogen with each other, indicating that iron serves more as a nutrient during bacterial growth rather than just a mineral. Magnetotactic bacteria have not only invoked some interest in the field of astrobiology for the last two decades, but are also prokaryotes having the unique ability of synthesizing membrane bound intracellular organelles. Our findings on these unique prokaryotes are a strong addition to the limited repertoire, of elemental compositions of living cells, aimed at exploring the chemical logic of life.

  12. 机械通气致下呼吸道黄杆菌属感染的临床研究%A clinical study on lower respiratory tract infections caused by Flavobacterium after mechanical ventilation

    Institute of Scientific and Technical Information of China (English)

    孙健龙; 张素梅; 管晓芸; 张仁仙; 宋秀琴

    2012-01-01

    目的 研究机械通气导致下呼吸道黄杆菌属感染的临床特点、黄杆菌属对抗菌药的敏感性,探讨预防措施.方法 对医院加强医疗室2001-2010年30例行机械通气发生下呼吸道黄杆菌属感染的临床资料进行回顾性调查.结果 30例机械通气发生下呼吸道黄杆菌属感染的病例均有基础疾病、长期应用多种抗菌药史;共分离出30株黄杆菌属,主要为脑膜脓毒金黄杆菌,占33.33%;黄杆菌属对红霉素、环丙沙星、磺胺甲噁唑/甲氧苄啶、克林霉素、万古霉素、利福平较敏感;30例患者死亡2例,死亡率为6.7%.结论 黄杆菌属引起的下呼吸道感染多发生在老年、有基础疾病、应用广谱抗菌药、进行机械通气治疗的患者,黄杆菌属耐药率较高;严格落实清洁、消毒、隔离措施、无菌操作规程,可以预防黄杆菌属的感染.%OBJECTIVE To explore the clinical characteristics of lower respiratory tract infections caused by Flavobacterium after mechanical ventilation, the susceptibility of Flavobacterium to antimicrobial agents so as to propose preventive measures. METHODS A total of 30 medical records of patients with lower respiratory tract infection caused by Flavobacterium after mechanical ventilation in ICU during 2001-2010 were investigated retrospectively. RESULTS All of 30 patients with Flavobacterium infections who underwent mechanical ventilation were complicated with underlying diseases and were with long-term use of antibiotics; of 30 strains of Flavobacterium isolated, Staphylococcus bacteria meningeal sepsis was the major species, accounting for 33.33%; Flavobacterium were susceptible to erythromycin, ciprofloxacin, trimethoprim/sulfamethoxazole, clindamycin, vancomycin, and rifampicins2 of 30 patients were dead with the mortality of 6. 1%. CONCLUSION Lower respiratory tract infections caused by Flavobacterium mainly occur in patients who are elderly, suffered from underlying

  13. Dispersal and Survival of Flavobacterium psychrophilum Phages In Vivo in Rainbow Trout and In Vitro under Laboratory Conditions: Implications for Their Use in Phage Therapy

    DEFF Research Database (Denmark)

    Madsen, Lone; Bertelsen, Sif K.; Dalsgaard, Inger;

    2013-01-01

    Attention has been drawn to phage therapy as an alternative approach for controlling pathogenic bacteria such as Flavobacterium psychrophilum in salmonid aquaculture, which can give rise to high mortalities, especially in rainbow trout fry. Recently, phages have been isolated with a broad host...... range and a strong lytic potential against pathogenic F. psychrophilum under experimental conditions. However, little is known about the fate of phages at environmental conditions. Here, we quantified the dispersal and fate of F. psychrophilum phages and hosts in rainbow trout fry after intraperitoneal...... injection. Both phages and bacteria were isolated from the fish organs for up to 10 days after injection, and coinjection with both bacteria and phages resulted in a longer persistence of the phage in the fish organs, than when the fish had been injected with the phages only. The occurrence of both phage...

  14. Immersion exposure of rainbow trout (Oncorhynchus mykiss) fry to wildtype Flavobacterium psychrophilum induces no mortality, but protects against later intraperitoneal challenge

    DEFF Research Database (Denmark)

    Lorenzen, Ellen; Brudeseth, B.E.; Wiklund, T.;

    2010-01-01

    .e. bathing in high titres of non-attenuated isolates of F. psychrophilum, was able to induce immunity to a subsequent ip challenge. Immersion in live bacteria for 30 or 50 min caused no mortality and protected a major fraction of the fry against challenges 26 and 47 days later with RPS values of 88.2 and 60......Flavobacterium psychrophilum, the causative agent of RTFS or rainbow trout fry syndrome, causes high mortality among hatchery reared rainbow trout (Oncorhynchus mykiss) fry in Europe and the USA. Despite several attempts, no efficient vaccines have yet been developed, the main obstacle being that...... the fry have to be vaccinated very early, i.e. around 0.2–0.5 g, where RTFS usually starts to give problems in the fish farms. Consequently, only oral or bath vaccines are relevant. Immersion of fry in inactivated or attenuated bacteria has resulted in RPS values of less than 50%. However, the results...

  15. Characterization of isolates of Flavobacterium psychrophilum associated with coldwater disease or rainbow trout fry syndrome I : phenotypic and genomic studies

    DEFF Research Database (Denmark)

    Lorenzen, Ellen; Dalsgaard, Inger; Bernardet, Jean-Francois

    1997-01-01

    characteristics, and compared with previously characterized French and American strains. DNA hybridization studies showed that the Danish isolates were highly related to the type strain, F. psychrophilum NCIMB 1947(T). Plasmid profiling of Danish isolates and those from other European countries revealed...... differences, which might be related to differences in pathogenicity. European isolates originating from clinical outbreaks of either RTFS or CND usually harboured one plasmid of 3.2 kb, whereas isolates originating from fish with different or no disease signs had other profiles. Phenotypically, the Danish...... isolates appeared very homogeneous and shared most characteristics with the type strain, and with French and American strains studied by other authors. Further studies on the importance of the plasmids and the proteolytic activities of the bacterium might help in elucidating possible virulence factors....

  16. Experimental evolution of aging in a bacterium

    Directory of Open Access Journals (Sweden)

    Stearns Stephen C

    2007-07-01

    Full Text Available Abstract Background Aging refers to a decline in reproduction and survival with increasing age. According to evolutionary theory, aging evolves because selection late in life is weak and mutations exist whose deleterious effects manifest only late in life. Whether the assumptions behind this theory are fulfilled in all organisms, and whether all organisms age, has not been clear. We tested the generality of this theory by experimental evolution with Caulobacter crescentus, a bacterium whose asymmetric division allows mother and daughter to be distinguished. Results We evolved three populations for 2000 generations in the laboratory under conditions where selection was strong early in life, but very weak later in life. All populations evolved faster growth rates, mostly by decreasing the age at first division. Evolutionary changes in aging were inconsistent. The predominant response was the unexpected evolution of slower aging, revealing the limits of theoretical predictions if mutations have unanticipated phenotypic effects. However, we also observed the spread of a mutation causing earlier aging of mothers whose negative effect was reset in the daughters. Conclusion Our results confirm that late-acting deleterious mutations do occur in bacteria and that they can invade populations when selection late in life is weak. They suggest that very few organisms – perhaps none- can avoid the accumulation of such mutations over evolutionary time, and thus that aging is probably a fundamental property of all cellular organisms.

  17. Genome Sequence of the Soil Bacterium Janthinobacterium sp. KBS0711

    OpenAIRE

    Shoemaker, William R.; Muscarella, Mario E.; Lennon, Jay T

    2015-01-01

    We present a draft genome of Janthinobacterium sp. KBS0711 that was isolated from agricultural soil. The genome provides insight into the ecological strategies of this bacterium in free-living and host-associated environments.

  18. Trichloroethylene Biodegradation by a Methane-Oxidizing Bacterium

    OpenAIRE

    Little, C. Deane; Palumbo, Anthony V; Herbes, Stephen E.; Lidstrom, Mary E.; Tyndall, Richard L.; Gilmer, Penny J.

    1988-01-01

    Trichloroethylene (TCE), a common groundwater contaminant, is a suspected carcinogen that is highly resistant to aerobic biodegradation. An aerobic, methane-oxidizing bacterium was isolated that degrades TCE in pure culture at concentrations commonly observed in contaminated groundwater. Strain 46-1, a type I methanotrophic bacterium, degraded TCE if grown on methane or methanol, producing CO2 and water-soluble products. Gas chromatography and 14C radiotracer techniques were used to determine...

  19. Taxonomic characterization of the cellulose-degrading bacterium NCIB 10462

    Energy Technology Data Exchange (ETDEWEB)

    Dees, C.; Ringleberg, D.; Scott, T.C. [Oak Ridge National Lab., TN (United States); Phelps, T. [Univ. of Tennessee, Knoxville, TN (United States)

    1994-06-01

    The gram negative cellulase-producing bacterium NCIB 10462 has been previously named Pseudomonas fluorescens subsp. or var. cellulosa. Since there is renewed interest in cellulose-degrading bacteria for use in bioconversion of cellulose to chemical feed stocks and fuels, we re-examined the characteristics of this microorganism to determine its proper taxonomic characterization and to further define it`s true metabolic potential. Metabolic and physical characterization of NCIB 10462 revealed that this was an alkalophilic, non-fermentative, gram negative, oxidase positive, motile, cellulose-degrading bacterium. The aerobic substrate utilization profile of this bacterium was found to have few characteristics consistent with a classification of P. fluorescens with a very low probability match with the genus Sphingomonas. Total lipid analysis did not reveal that any sphingolipid bases are produced by this bacterium. NCIB 10462 was found to grow best aerobically but also grows well in complex media under reducing conditions. NCIB 10462 grew slowly under full anaerobic conditions on complex media but growth on cellulosic media was found only under aerobic conditions. Total fatty acid analysis (MIDI) of NCIB 10462 failed to group this bacterium with a known pseudomonas species. However, fatty acid analysis of the bacteria when grown at temperatures below 37{degrees}C suggest that the organism is a pseudomonad. Since a predominant characteristic of this bacterium is it`s ability to degrade cellulose, we suggest it be called Pseudomonas cellulosa.

  20. Transcriptomic analysis of the head kidney of Topmouth culter (Culter alburnus) infected with Flavobacterium columnare with an emphasis on phagosome pathway.

    Science.gov (United States)

    Zhao, Lijuan; Tu, Jiagang; Zhang, Yulei; Wang, Jinfu; Yang, Ling; Wang, Weimin; Wu, Zaohe; Meng, Qinglei; Lin, Li

    2016-10-01

    Flavobacterium columnare (FC) has caused worldwide fish columnaris disease with high mortality and great economic losses in cultured fish, including Topmouth culter (Culter alburnus). However, the knowledge about the host factors involved in FC infection is little known. In this study, the transcriptomic profiles of the head kidney from Topmouth culter with or without FC infection were obtained using HiSeq™ 2500 (Illumina). Totally 79,641 unigenes with high quality were obtained. Among them, 4037 differently expressed genes, including 1217 up-regulated and 2820 down-regulated genes, were identified and enriched using databases of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). The differently expressed genes were mainly associated with pathways such as immune response, carbohydrate metabolism, amino acid metabolism, and lipid metabolism. Since phagocytosis is a central mechanism of innate immune response by host cells to defense against infectious agents, genes related to the phagosome pathway were scrutinized and 9 differently expressed phagosome-related genes were identified including 3 up-regulated and 6 down-regulated genes. Five of them were further validated by quantitative real-time polymerase chain reaction (qRT-PCR). This transcriptomic analysis of host genes in response to FC infection provides data towards understanding the infection mechanisms and will shed a new light on the prevention of columnaris. PMID:27601296

  1. Flavobacterium psychrophilum y su patología en alevines de Onchorhynchus mykiss del centro piscícola El Ingenio, Huancayo

    Directory of Open Access Journals (Sweden)

    Jorge León

    2008-12-01

    Full Text Available En el presente trabajo se reporta la presencia de Flavobacterium psychrophilum, como agente causante de la patología “enfermedad bacteriana del agua fría” en alevines de Onchorhynchus mykiss “trucha arco iris” del Centro Piscícola El Ingenio, Junín (3250 m de altitud. La lesión macroscópica externa más frecuente fue la ulceración profunda de la región dorsal del pez acompañado de un ennegrecimiento localizado de la piel. Internamente se observó una marcada esplenomegalia, palidez del hígado, riñón y branquias, inflamación del intestino y acumulación de líquido ascítico en el peritoneo. No se detectó hemorragia interna. En Agar Cytophaga Modificado (ACM según Anaker & Ordal (1959 fueron aisladas inicialmente 29 Gram negativas, de las cuales según la caracterización fenotípica y pruebas bioquímicas 9 fueron consideradas como F. psychrophilum. Pruebas de susceptibilidad antibiótica mostraron alta sensibilidad de las cepas a Gentamicina, Ceftazidina, oxitetraciclina, Norfloxacina, furazolidona, Ciprofloxacina y Cefoxitina.

  2. Transcriptomic analysis of the head kidney of Topmouth culter (Culter alburnus) infected with Flavobacterium columnare with an emphasis on phagosome pathway.

    Science.gov (United States)

    Zhao, Lijuan; Tu, Jiagang; Zhang, Yulei; Wang, Jinfu; Yang, Ling; Wang, Weimin; Wu, Zaohe; Meng, Qinglei; Lin, Li

    2016-10-01

    Flavobacterium columnare (FC) has caused worldwide fish columnaris disease with high mortality and great economic losses in cultured fish, including Topmouth culter (Culter alburnus). However, the knowledge about the host factors involved in FC infection is little known. In this study, the transcriptomic profiles of the head kidney from Topmouth culter with or without FC infection were obtained using HiSeq™ 2500 (Illumina). Totally 79,641 unigenes with high quality were obtained. Among them, 4037 differently expressed genes, including 1217 up-regulated and 2820 down-regulated genes, were identified and enriched using databases of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). The differently expressed genes were mainly associated with pathways such as immune response, carbohydrate metabolism, amino acid metabolism, and lipid metabolism. Since phagocytosis is a central mechanism of innate immune response by host cells to defense against infectious agents, genes related to the phagosome pathway were scrutinized and 9 differently expressed phagosome-related genes were identified including 3 up-regulated and 6 down-regulated genes. Five of them were further validated by quantitative real-time polymerase chain reaction (qRT-PCR). This transcriptomic analysis of host genes in response to FC infection provides data towards understanding the infection mechanisms and will shed a new light on the prevention of columnaris.

  3. Hydrogen Production by the Thermophilic Bacterium Thermotoga neapolitana

    Directory of Open Access Journals (Sweden)

    Nirakar Pradhan

    2015-06-01

    Full Text Available As the only fuel that is not chemically bound to carbon, hydrogen has gained interest as an energy carrier to face the current environmental issues of greenhouse gas emissions and to substitute the depleting non-renewable reserves. In the last years, there has been a significant increase in the number of publications about the bacterium Thermotoga neapolitana that is responsible for production yields of H2 that are among the highest achievements reported in the literature. Here we present an extensive overview of the most recent studies on this hyperthermophilic bacterium together with a critical discussion of the potential of fermentative production by this bacterium. The review article is organized into sections focused on biochemical, microbiological and technical issues, including the effect of substrate, reactor type, gas sparging, temperature, pH, hydraulic retention time and organic loading parameters on rate and yield of gas production.

  4. Rnf Genes in Purple Sulfur Bacterium Allochromatium vinosum

    OpenAIRE

    DİNÇTÜRK, H. Benan; DEMİR, Volkan

    2006-01-01

    Allochromatium vinosum is a photosynthetic, diazotrophic purple sulfur bacterium that oxidizes reduced sulfur compounds hydrogen sulfide, elemental sulfur and thiosulfide. In this article, we report the presence of rnf genes in Allochromatium vinosum, some of which have been reported to take part in nitrogen fixation in some species.

  5. Draft Genome Sequence of Oral Bacterium Streptococcus mutans JH1140

    OpenAIRE

    Escano, Jerome; Deng, Peng; Lu, Shi-En; Smith, Lief

    2016-01-01

    Streptococcus mutans JH1140 is an oral bacterium known to produce the bacteriocin mutacin 1140, and the strain has been genetically engineered to combat dental caries. Here, we report the 2.0-Mb draft genome of S. mutans JH1140. This genome provides new insights into the strain’s superior colonization properties and its utility in replacement therapy.

  6. Genome of a mosquito-killing bacterium decoded

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ Researchers with the CAS Wuhan Institute of Virology (WHIOV) recently completed the genome sequencing of a mosquitocidal bacterium Bacillus shaericus C3-41. The feat, first of its kind in China, is expected to further promote the bio-control studies of mosquitoes.

  7. Cloning of a Chryseobacterium (Flavobacterium) meningosepticum Chromosomal Gene (blaACME) Encoding an Extended-Spectrum Class A β-Lactamase Related to the Bacteroides Cephalosporinases and the VEB-1 and PER β-Lactamases

    OpenAIRE

    Rossolini, Gian Maria; Franceschini, Nicola; Lauretti, Laura; Caravelli, Berardo; Riccio, Maria Letizia; Galleni, Moreno; Frère, Jean-Marie; Amicosante, Gianfranco

    1999-01-01

    In addition to the BlaB metallo-β-lactamase, Chryseobacterium (Flavobacterium) meningosepticum CCUG 4310 (NCTC 10585) constitutively produces a 31-kDa active-site serine β-lactamase, named CME-1, with an alkaline isoelectric pH. The blaACME gene that encodes the latter enzyme was isolated from a genomic library constructed in the Escherichia coli plasmid vector pACYC184 by screening for cefuroxime-resistant clones. Sequence analysis revealed that the CME-1 enzyme is a new class A β-lactamase ...

  8. Shotgun Genome Sequence of the Large Purple Photosynthetic Bacterium Rhodospirillum photometricum DSM122

    OpenAIRE

    Duquesne, K.; Sturgis, James N.

    2012-01-01

    Here, we present the shotgun genome sequence of the purple photosynthetic bacterium Rhodospirillum photometricum DSM122. The photosynthetic apparatus of this bacterium has been particularly well studied by microscopy. The knowledge of the genome of this oversize bacterium will allow us to compare it with the other purple bacterial organisms to follow the evolution of the photosynthetic apparatus.

  9. Generation of Biotechnology-Derived Flavobacterium columnare Ghosts by PhiX174 Gene E-Mediated Inactivation and the Potential as Vaccine Candidates against Infection in Grass Carp

    Directory of Open Access Journals (Sweden)

    Wenxing Zhu

    2012-01-01

    Full Text Available Flavobacterium columnare is a bacterial pathogen causing high mortality rates for many freshwater fish species. Fish vaccination with a safe and effective vaccine is a potential approach for prevention and control of fish disease. Here, in order to produce bacterial ghost vaccine, a specific Flavobacterium lysis plasmid pBV-E-cat was constructed by cloning PhiX174 lysis gene E and the cat gene with the promoter of F. columnare into the prokaryotic expression vector pBV220. The plasmid was successfully electroporated into the strain F. columnare G4cpN22 after curing of its endogenous plasmid. F. columnare G4cpN22 ghosts (FCGs were generated for the first time by gene E-mediated lysis, and the vaccine potential of FCG was investigated in grass carp (Ctenopharyngodon idellus by intraperitoneal route. Fish immunized with FCG showed significantly higher serum agglutination titers and bactericidal activity than fish immunized with FKC or PBS. Most importantly, after challenge with the parent strain G4, the relative percent survival (RPS of fish in FCG group (70.9% was significantly higher than FKC group (41.9%. These results showed that FCG could confer immune protection against F. columnare infection. As a nonliving whole cell envelope preparation, FCG may provide an ideal alternative to pathogen-based vaccines against columnaris in aquaculture.

  10. Rock Phosphate Solubilization Mechanisms of One Fungus and One Bacterium

    Institute of Scientific and Technical Information of China (English)

    LIN Qi-mei; ZHAO Xiao-rong; ZHAO Zi-juan; LI Bao-guo

    2002-01-01

    Many microorganisms can dissolve the insoluble phosphates like apatite. However, the mechanisms are still not clear. This study was an attempt to investigate the mechanisms of rock phosphate solubilization by an Aspergillus 2TCiF2 and an Arthrobacter1TCRi7. The results indicated that the fungus produced a large amount of organic acids, mainly oxalic acid. The total quantity of the organic acids produced by the fungus was 550 times higher than that by the bacterium. Different organic acids had completely different capacities to solubilize the rock. Oxalic acid and citric acid had stronger capacity to dissolve the rock than malic acid, tartaric acid, lactic acid, acetic acid, malonic acid and succinic acid. The fungus solubilized the rock through excreting both proton and organic acids. The rock solubilization of the bacterium depended on only proton.

  11. A Streamlined Strategy for Biohydrogen Production with an Alkaliphilic Bacterium

    Energy Technology Data Exchange (ETDEWEB)

    Elias, Dwayne A [ORNL; Wall, Judy D. [University of Missouri; Mormile, Dr. Melanie R. [Missouri University of Science and Technology; Begemann, Matthew B [University of Wisconsin, Madison

    2012-01-01

    Biofuels are anticipated to enable a shift from fossil fuels for renewable transportation and manufacturing fuels, with biohydrogen considered attractive since it could offer the largest reduction of global carbon budgets. Currently, biohydrogen production remains inefficient and heavily fossil fuel-dependent. However, bacteria using alkali-treated biomass could streamline biofuel production while reducing costs and fossil fuel needs. An alkaliphilic bacterium, Halanaerobium strain sapolanicus, is described that is capable of biohydrogen production at levels rivaling neutrophilic strains, but at pH 11 and hypersaline conditions. H. sapolanicus ferments a variety of 5- and 6- carbon sugars derived from hemicellulose and cellulose including cellobiose, and forms the end products hydrogen and acetate. Further, it can also produce biohydrogen from switchgrass and straw pretreated at temperatures far lower than any previously reported and in solutions compatible with growth. Hence, this bacterium can potentially increase the efficiency and efficacy of biohydrogen production from renewable biomass resources.

  12. A physical map of the hyperthermophilic bacterium Aquifex pyrophilus chromosome.

    OpenAIRE

    Shao, Z; Mages, W; Schmitt, R.

    1994-01-01

    A genomic map of the hyperthermophilic hydrogen-oxidizing bacterium Aquifex pyrophilus was established with NotI (GC/GGCCGC), SpeI (A/CTAGT), and XbaI (T/CTAGA). Linking clones and cross-hybridization of restriction fragments revealed a single circular chromosome of 1.6 Mbp. A single flagellin gene and six rRNA gene units were located on this map by Southern hybridization.

  13. Isolation of a Bacterium Capable of Degrading Peanut Hull Lignin

    OpenAIRE

    Kerr, Thomas J.; Kerr, Robert D.; Benner, Ronald

    1983-01-01

    Thirty-seven bacterial strains capable of degrading peanut hull lignin were isolated by using four types of lignin preparations and hot-water-extracted peanut hulls. One of the isolates, tentatively identified as Arthrobacter sp., was capable of utilizing all four lignin preparations as well as extracted peanut hulls as a sole source of carbon. The bacterium was also capable of degrading specifically labeled [14C]lignin-labeled lignocellulose and [14C]cellulose-labeled lignocellulose from the...

  14. Growth of a Strictly Anaerobic Bacterium on Furfural (2-Furaldehyde)

    OpenAIRE

    Brune, Gerhard; Schoberth, Siegfried M.; Sahm, Hermann

    1983-01-01

    A strictly anaerobic bacterium was isolated from a continuous fermentor culture which converted the organic constituents of sulfite evaporator condensate to methane and carbon dioxide. Furfural is one of the major components of this condensate. This furfural isolate could degrade furfural as the sole source of carbon and energy in a defined mineral-vitamin-sulfate medium. Acetic acid was the major fermentation product. This organism could also use ethanol, lactate, pyruvate, or fumarate and c...

  15. A deep-sea bacterium with unique nitrifying property

    Digital Repository Service at National Institute of Oceanography (India)

    Ram, A.; LokaBharathi, P.A.; Nair, S.; Chandramohan, D.

    cember 2000 A deep - sea bacterium with unique n i trifying property A. S. Pradeep Ram, P. A. Loka Bharathi*, Shanta Nair and D. Chandramohan Department of Microbiology, National Institute of Oceanography, Dona Paula, Goa 403 004..., nitrite oxidizers have been shown to augment chemolithotrophic lifestyle with heterotrophic me tab o lism of simple carbon substrate 17 . Retaining both the traits enables them to exploit unique niches several centimetres bsf, where carbon or energy...

  16. An on-bacterium flow cytometric immunoassay for protein quantification.

    Science.gov (United States)

    Lan, Wen-Jun; Lan, Wei; Wang, Hai-Yan; Yan, Lei; Wang, Zhe-Li

    2013-09-01

    The polystyrene bead-based flow cytometric immunoassay has been widely reported. However, the preparation of functional polystyrene bead is still inconvenient. This study describes a simple and easy on-bacterium flow cytometric immunoassay for protein quantification, in which Staphylococcus aureus (SAC) is used as an antibody-antigen carrier to replace the polystyrene bead. The SAC beads were prepared by carboxyfluorescein diacetate succinimidyl ester (CFSE) labeling, paraformaldehyde fixation and antibody binding. Carcinoembryonic antigen (CEA) and cytokeratin-19 fragment (CYFRA 21-1) proteins were used as models in the test system. Using prepared SAC beads, biotinylated proteins, and streptavidin-phycoerythrin (SA-PE), the on-bacterium flow cytometric immunoassay was validated by quantifying CEA and CYFRA 21-1 in sample. Obtained data demonstrated a concordant result between the logarithm of the protein concentration and the logarithm of the PE mean fluorescence intensity (MFI). The limit of detection (LOD) in this immunoassay was at least 0.25 ng/ml. Precision and accuracy assessments appeared that either the relative standard deviation (R.S.D.) or the relative error (R.E.) was CYFRA 21-1. In conclusion, the on-bacterium flow cytometric immunoassay may be of use in the quantification of serum protein. PMID:23739299

  17. Salt-inducible promoter derivable from a lactic acid bacterium, and its use in a lactic acid bacterium for production of a desired protein

    NARCIS (Netherlands)

    Sanders, Jan Willem; Kok, Jan; Venema, Gerard; Ledeboer, Adrianus Marinus

    1998-01-01

    The invention provides a salt-inducible promoter present in SEQ ID NO: 10 and derivable from a lactic acid bacterium in isolation from the coding sequence normally controlled by said promoter in a wild-type lactic acid bacterium, with modifications and important parts thereof. Also provided are a re

  18. The complete genome, structural proteome, comparative genomics and phylogenetic analysis of a broad host lytic bacteriophage ϕD3 infecting pectinolytic Dickeya spp. : Standards in Genomic Sciences

    NARCIS (Netherlands)

    Czajkowski, Robert; Ozymko, Zofia; Siwinska, Joanna; Ossowicki, Adam; de Jager, Victor; Narajczyk, Magdalena; Łojkowska, Ewa

    2015-01-01

    Flavobacterium seoulense strain EM1321T is the type strain of Flavobacterium seoulense sp. nov., a proposed novel species within the genus Flavobacterium. This strain is a Gram-reaction-negative, aerobic, rod-shaped bacterium isolated from stream water in Bukhansan National Park, Seoul. This organis

  19. Detection and Quantification of Flavobacterium psychrophilum-Specific Bacteriophages In Vivo in Rainbow Trout upon Oral Administration: Implications for Disease Control in Aquaculture

    Science.gov (United States)

    Christiansen, Rói Hammershaimb; Dalsgaard, Inger; Middelboe, Mathias; Lauritsen, Anne H.

    2014-01-01

    The use of bacteriophages in the treatment and prevention of infections by the fish pathogen Flavobacterium psychrophilum has attracted increased attention in recent years. It has been shown recently that phage delivery via the parenteral route resulted in immediate distribution of phages to the circulatory system and the different organs. However, little is known about phage dispersal and survival in vivo in rainbow trout after delivery via the oral route. Here we examined the dispersal and survival of F. psychrophilum phage FpV-9 in vivo in juvenile rainbow trout after administration by three different methods—bath, oral intubation into the stomach, and phage-coated feed—with special emphasis on the oral route of delivery. Phages could be detected in all the organs investigated (intestine, spleen, brain, and kidney) 0.5 h postadministration, reaching concentrations as high as ∼105 PFU mg intestine−1 and ∼103 PFU mg spleen−1 within the first 24 h following the bath and ∼107 PFU mg intestine−1 and ∼104 PFU mg spleen−1 within the first 24 h following oral intubation. The phages were most persistent in the organs for the first 24 h and then decreased exponentially; no phages were detected after 83 h in the organs investigated. Phage administration via feed resulted in the detection of phages in the intestine, spleen, and kidney 1 h after feeding. Average concentrations of ∼104 PFU mg intestine−1 and ∼101 PFU mg spleen−1 were found throughout the experimental period (200 h) following continuous delivery of phages with feed. These experiments clearly demonstrate the ability of the phages to survive passage through the fish stomach and to penetrate the intestinal barrier and enter the circulatory system after oral delivery, although the quantity of phages found in the spleen was 100- to 1,000-fold lower than that in the intestine. It was also shown that phages could tolerate long periods of desiccation on the feed pellets, with 60% survival

  20. Detection and quantification of Flavobacterium psychrophilum-specific bacteriophages in vivo in rainbow trout upon oral administration: implications for disease control in aquaculture.

    Science.gov (United States)

    Christiansen, Rói Hammershaimb; Dalsgaard, Inger; Middelboe, Mathias; Lauritsen, Anne H; Madsen, Lone

    2014-12-01

    The use of bacteriophages in the treatment and prevention of infections by the fish pathogen Flavobacterium psychrophilum has attracted increased attention in recent years. It has been shown recently that phage delivery via the parenteral route resulted in immediate distribution of phages to the circulatory system and the different organs. However, little is known about phage dispersal and survival in vivo in rainbow trout after delivery via the oral route. Here we examined the dispersal and survival of F. psychrophilum phage FpV-9 in vivo in juvenile rainbow trout after administration by three different methods-bath, oral intubation into the stomach, and phage-coated feed-with special emphasis on the oral route of delivery. Phages could be detected in all the organs investigated (intestine, spleen, brain, and kidney) 0.5 h postadministration, reaching concentrations as high as ∼10(5) PFU mg intestine(-1) and ∼10(3) PFU mg spleen(-1) within the first 24 h following the bath and ∼10(7) PFU mg intestine(-1) and ∼10(4) PFU mg spleen(-1) within the first 24 h following oral intubation. The phages were most persistent in the organs for the first 24 h and then decreased exponentially; no phages were detected after 83 h in the organs investigated. Phage administration via feed resulted in the detection of phages in the intestine, spleen, and kidney 1 h after feeding. Average concentrations of ∼10(4) PFU mg intestine(-1) and ∼10(1) PFU mg spleen(-1) were found throughout the experimental period (200 h) following continuous delivery of phages with feed. These experiments clearly demonstrate the ability of the phages to survive passage through the fish stomach and to penetrate the intestinal barrier and enter the circulatory system after oral delivery, although the quantity of phages found in the spleen was 100- to 1,000-fold lower than that in the intestine. It was also shown that phages could tolerate long periods of desiccation on the feed pellets, with 60

  1. Hymenobacter roseosalivarius gen. nov., sp. nov. from continental Antartica soils and sandstone: bacteria of the Cytophaga/Flavobacterium/Bacteroides line of phylogenetic descent.

    Science.gov (United States)

    Hirsch, P; Ludwig, W; Hethke, C; Sittig, M; Hoffmann, B; Gallikowski, C A

    1998-08-01

    Aseptically collected sandstone and soil samples from the antarctic Dry Valleys were inoculated into oligotrophic media and incubated under low light intensities. A total of 41 Gram-negative isolates were obtained with reddish colonies spreading on agar. A sandstone isolate and four soil strains were characterized further. They were nearly identical in morphological, physiological, biochemical and chemotaxonomic properties. They produced large amounts of extracellular polymer and utilized for growth: glucose, saccharose, mannitol, sorbitol, L-aspartate, malate and acetate, but not D-ribose, adonitol, DL-alanine, glutamate, glycolate, lactate or succinate. All strains hydrolyzed gelatin, starch, casein, xylan, Tweens 80 or 60 and dead or living yeast cells, but not cellulose or pectin. Nitrate was not reduced, ethanol was not oxidized and acid was not produced from maltose, mannitol or dulcitol. Ammonia was not produced from peptone. They were strictly aerobic. Major fatty acids were n 16:1 d 9, n 16:1 d 11, n 17:1 d 11, and i 15:0. The strains contained the quinone MK-7 and phosphatidylethanolamine as the main phospholipid. The base ratio ranged from 55 to 61 mol% G+C. A 16S rRNA sequence analysis of strains AA-688 and AA-718 showed these to be identical and to represent a special phylogenetic group within the Cytophaga/Flavobacterium/Bacteroides major line of descent. Three soil strains labeled "Taxeobacter" Txc1, Txg1, and Txo1 (Reichenbach, 1992) belonged to the same group but had lower sequence similarities (<95%). Some of their characteristics were different from those of the antarctic strains: the utilization of C-compounds, hydrolysis of polymers, temperature tolerances, major fatty acids and base ratios. Txc1 and Txg1 may later have to be considered as members of this group, possibly on the species level, while Txo1 could represent a different related genus. It is concluded that the five antarctic strains represent a new genus and species for which the name

  2. Research Progress and Perspectives of Nitrogen Fixing Bacterium, Gluconacetobacter diazotrophicus, in Monocot Plants

    Directory of Open Access Journals (Sweden)

    N. Eskin

    2014-01-01

    Full Text Available Gluconacetobacter diazotrophicus is a nitrogen fixing bacterium originally found in monocotyledon sugarcane plants in which the bacterium actively fixes atmosphere nitrogen and provides significant amounts of nitrogen to plants. This bacterium mainly colonizes intercellular spaces within the roots and stems of plants and does not require the formation of the complex root organ like nodule. The bacterium is less plant/crop specific and indeed G. diazotrophicus has been found in a number of unrelated plant species. Importantly, as the bacterium was of monocot plant origin, there exists a possibility that the nitrogen fixation feature of the bacterium may be used in many other monocot crops. This paper reviews and updates the research progress of G. diazotrophicus for the past 25 years but focuses on the recent research development.

  3. Fast Neutron Irradiation of the Highly Radioresistant Bacterium Deinococcus Radiodurans

    Science.gov (United States)

    Case, Diane Louise

    Fast neutron dose survival curves were generated for the bacterium Deinococcus radiodurans, which is renowned for its unusually high resistance to gamma, x-ray, and ultraviolet radiation, but for which fast neutron response was unknown. The fast neutrons were produced by the University of Massachusetts Lowell 5.5-MV, type CN Van de Graaff accelerator through the ^7Li(p,n)^7 Be reaction by bombarding a thick metallic lithium target with a 4-MeV proton beam. The bacteria were uniformly distributed on 150-mm agar plates and were exposed to the fast neutron beam under conditions of charged particle equilibrium. The plates were subdivided into concentric rings of increasing diameter from the center to the periphery of the plate, within which the average neutron dose was calculated as the product of the precisely known neutron fluence at the average radius of the ring and the neutron energy dependent kerma factor. The neutron fluence and dose ranged from approximately 3 times 1013 n cm^ {-2} to 1 times 1012 n cm^ {-2}, and 200 kilorad to 5 kilorad, respectively, from the center to the periphery of the plate. Percent survival for Deinococcus radiodurans as a function of fast neutron dose was derived from the ability of the irradiated cells to produce visible colonies within each ring compared to that of a nonirradiated control population. The bacterium Escherichia coli B/r (CSH) was irradiated under identical conditions for comparative purposes. The survival response of Deinococcus radiodurans as a result of cumulative fast neutron exposures was also investigated. The quantification of the ability of Deinococcus radiodurans to survive cellular insult from secondary charged particles, which are produced by fast neutron interactions in biological materials, will provide valuable information about damage and repair mechanisms under extreme cellular stress, and may provide new insight into the origin of this bacterium's unprecedented radiation resistance.

  4. Phosphate enhances levan production in the endophytic bacterium Gluconacetobacter diazotrophicus Pal5

    OpenAIRE

    Idogawa, Nao; Amamoto, Ryuta; Murata, Kousaku; Kawai, Shigeyuki

    2014-01-01

    Gluconacetobacter diazotrophicus is a gram-negative and endophytic nitrogen-fixing bacterium that has several beneficial effects in host plants; thus, utilization of this bacterium as a biofertilizer in agriculture may be possible. G. diazotrophicus synthesizes levan, a D-fructofuranosyl polymer with β-(2→6) linkages, as an exopolysaccharide and the synthesized levan improves the stress tolerance of the bacterium. In this study, we found that phosphate enhances levan production by G. diazotro...

  5. A Plant Growth-Promoting Bacterium That Decreases Nickel Toxicity in Seedlings

    OpenAIRE

    Burd, Genrich I.; Dixon, D. George; Glick, Bernard R.

    1998-01-01

    A plant growth-promoting bacterium, Kluyvera ascorbata SUD165, that contained high levels of heavy metals was isolated from soil collected near Sudbury, Ontario, Canada. The bacterium was resistant to the toxic effects of Ni2+, Pb2+, Zn2+, and CrO4−, produced a siderophore(s), and displayed 1-aminocyclopropane-1-carboxylic acid deaminase activity. Canola seeds inoculated with this bacterium and then grown under gnotobiotic conditions in the presence of high concentrations of nickel chloride w...

  6. Magnetic guidance of the magnetotactic bacterium Magnetospirillum gryphiswaldense.

    Science.gov (United States)

    Loehr, Johannes; Pfeiffer, Daniel; Schüler, Dirk; Fischer, Thomas M

    2016-04-21

    Magnetospirillum gryphiswaldense is a magnetotactic bacterium with a permanent magnetic moment capable of swimming using two bipolarly located flagella. In their natural environment these bacteria swim along the field lines of the homogeneous geomagnetic field in a typical run and reversal pattern and thereby create non-differentiable trajectories with sharp edges. In the current work we nevertheless achieve stable guidance along curved lines of mechanical instability by using a heterogeneous magnetic field of a garnet film. The successful guidance of the bacteria depends on the right balance between motility and the magnetic moment of the magnetosome chain. PMID:26972517

  7. Intracellular iron minerals in a dissimilatory iron-reducing bacterium.

    Science.gov (United States)

    Glasauer, Susan; Langley, Sean; Beveridge, Terry J

    2002-01-01

    Among prokaryotes, there are few examples of controlled mineral formation; the formation of crystalline iron oxides and sulfides [magnetite (Fe3O4) or greigite (Fe3S4)] by magnetotactic bacteria is an exception. Shewanella putrefaciens CN32, a Gram-negative, facultative anaerobic bacterium that is capable of dissimilatory iron reduction, produced microscopic intracellular grains of iron oxide minerals during growth on two-line ferrihydrite in a hydrogen-argon atmosphere. The minerals, formed at iron concentrations found in the soil and sedimentary environments where these bacteria are active, could represent an unexplored pathway for the cycling of iron by bacteria. PMID:11778045

  8. Factors Affecting Zebra Mussel Kill by the Bacterium Pseudomonas fluorescens

    Energy Technology Data Exchange (ETDEWEB)

    Daniel P. Molloy

    2004-02-24

    The specific purpose of this research project was to identify factors that affect zebra mussel kill by the bacterium Pseudomonas fluorescens. Test results obtained during this three-year project identified the following key variables as affecting mussel kill: treatment concentration, treatment duration, mussel siphoning activity, dissolved oxygen concentration, water temperature, and naturally suspended particle load. Using this latter information, the project culminated in a series of pipe tests which achieved high mussel kill inside power plants under once-through conditions using service water in artificial pipes.

  9. Screening, identification and desilication of a silicate bacterium

    Institute of Scientific and Technical Information of China (English)

    ZHOU Hong-bo; ZENG Xiao-xi; LIU Fei-fei; QIU Guan-zhou; HU Yue-hua

    2006-01-01

    The strain Lv1-2 isolated from the Henan bauxite was characterized by morphological observation, biochemical and physiological identification, and 16S rDNA sequence analysis. The influences of temperature, initial pH value, the volume of medium, shaking speed and illite concentration on the desilicating ability of the strain Lv1-2 were investigated. The results show that the bacterium is a Gram-negative rod-shaped bacterium with oval endspores and thick capsule, but without flagellum. The biochemical and physiological tests indicate that the strain Lv1-2 is similar to Bacillus mucilaginosus. In GenBank the 16S rDNA sequence similarity of the strain Lv1-2 and the B. mucilaginosus YNUCC0001 (AY571332) is more than 99 %. Based on the above results, the strain Lv1-2 is identified as B. mucilaginosus. The optimum conditions for the strain Lv1-2 to remove silicon from illite are as follows: temperature is 30℃ ;initial pH value is 7.5; medium volume in 200 mL bottle is 60 mL; shaking speed of rotary shaker is 220 r/m; illite concentration is 1%.

  10. Biological Control of Meloidogyne hapla Using an Antagonistic Bacterium

    Directory of Open Access Journals (Sweden)

    Jiyeong Park

    2014-09-01

    Full Text Available We examined the efficacy of a bacterium for biocontrol of the root-knot nematode (RKN Meloidogyne hapla in carrot (Daucus carota subsp. sativus and tomato (Solanum lycopersicum. Among 542 bacterial isolates from various soils and plants, the highest nematode mortality was observed for treatments with isolate C1-7, which was identified as Bacillus cereus based on cultural and morphological characteristics, the Biolog program, and 16S rRNA sequencing analyses. The population density and the nematicidal activity of B. cereus C1-7 remained high until the end of culture in brain heart infusion broth, suggesting that it may have sustainable biocontrol potential. In pot experiments, the biocontrol efficacy of B. cereus C1-7 was high, showing complete inhibition of root gall or egg mass formation by RKN in carrot and tomato plants, and subsequently reducing RKN damage and suppressing nematode population growth, respectively. Light microscopy of RKN-infected carrot root tissues treated with C1-7 showed reduced formation of gall cells and fully developed giant cells, while extensive gall cells and fully mature giant cells with prominent cell wall ingrowths formed in the untreated control plants infected with RKNs. These histopathological characteristics may be the result of residual or systemic biocontrol activity of the bacterium, which may coincide with the biocontrol efficacies of nematodes in pots. These results suggest that B. cereus C1-7 can be used as a biocontrol agent for M. hapla.

  11. Polysaccharide degradation systems of the saprophytic bacterium Cellvibrio japonicus.

    Science.gov (United States)

    Gardner, Jeffrey G

    2016-07-01

    Study of recalcitrant polysaccharide degradation by bacterial systems is critical for understanding biological processes such as global carbon cycling, nutritional contributions of the human gut microbiome, and the production of renewable fuels and chemicals. One bacterium that has a robust ability to degrade polysaccharides is the Gram-negative saprophyte Cellvibrio japonicus. A bacterium with a circuitous history, C. japonicus underwent several taxonomy changes from an initially described Pseudomonas sp. Most of the enzymes described in the pre-genomics era have also been renamed. This review aims to consolidate the biochemical, structural, and genetic data published on C. japonicus and its remarkable ability to degrade cellulose, xylan, and pectin substrates. Initially, C. japonicus carbohydrate-active enzymes were studied biochemically and structurally for their novel polysaccharide binding and degradation characteristics, while more recent systems biology approaches have begun to unravel the complex regulation required for lignocellulose degradation in an environmental context. Also included is a discussion for the future of C. japonicus as a model system, with emphasis on current areas unexplored in terms of polysaccharide degradation and emerging directions for C. japonicus in both environmental and biotechnological applications. PMID:27263016

  12. Structure and morphology of magnetite anaerobically-produced by a marine magnetotactic bacterium and a dissimilatory iron-reducing bacterium

    Science.gov (United States)

    Sparks, N.H.C.; Mann, S.; Bazylinski, D.A.; Lovley, D.R.; Jannasch, H.W.; Frankel, R.B.

    1990-01-01

    Intracellular crystals of magnetite synthesized by cells of the magnetotactic vibroid organism, MV-1, and extracellular crystals of magnetite produced by the non-magnetotactic dissimilatory iron-reducing bacterium strain GS-15, were examined using high-resolution transmission electron microscopy, electron diffraction and 57Fe Mo??ssbauer spectroscopy. The magnetotactic bacterium contained a single chain of approximately 10 crystals aligned along the long axis of the cell. The crystals were essentially pure stoichiometric magnetite. When viewed along the crystal long axis the particles had a hexagonal cross-section whereas side-on they appeared as rectangules or truncated rectangles of average dimension, 53 ?? 35 nm. These findings are explained in terms of a three-dimensional morphology comprising a hexagonal prism of {110} faces which are capped and truncated by {111} end faces. Electron diffraction and lattice imaging studies indicated that the particles were structurally well-defined single crystals. In contrast, magnetite particles produced by the strain, GS-15 were irregular in shape and had smaller mean dimensions (14 nm). Single crystals were imaged but these were not of high structural perfection. These results highlight the influence of intracellular control on the crystallochemical specificity of bacterial magnetites. The characterization of these crystals is important in aiding the identification of biogenic magnetic materials in paleomagnetism and in studies of sediment magnetization. ?? 1990.

  13. Structure and morphology of magnetite anaerobically-produced by a marine magnetotactic bacterium and a dissimilatory iron-reducing bacterium

    Science.gov (United States)

    Sparks, N. H. C.; Mann, S.; Bazylinski, D. A.; Lovley, D. R.; Jannasch, H. W.; Frankel, R. B.

    1990-04-01

    Intracellular crystals of magnetite synthesized by cells of the magnetotactic vibroid organism, MV-1, and extracellular crystals of magnetite produced by the non-magnetotactic dissimilatory iron-reducing bacterium strain GS-15, were examined using high-resolution transmission electron microscopy, electron diffraction and 57Fe Mo¨ssbauer spectroscopy. The magnetotactic bacterium contained a single chain of approximately 10 crystals aligned along the long axis of the cell. The crystals were essentially pure stoichiometric magnetite. When viewed along the crystal long axis the particles had a hexagonal cross-section whereas side-on they appeared as rectangules or truncated rectangles of average dimension, 53 × 35 nm. These findings are explained in terms of a three-dimensional morphology comprising a hexagonal prism of 110 faces which are capped and truncated by 111 end faces. Electron diffraction and lattice imaging studies indicated that the particles were structurally well-defined single crystals. In contrast, magnetite particles produced by the strain, GS-15 were irregular in shape and had smaller mean dimensions (14 nm). Single crystals were imaged but these were not of high structural perfection. These results highlight the influence of intracellular control on the crystallochemical specificity of bacterial magnetites. The characterization of these crystals is important in aiding the identification of biogenic magnetic materials in paleomagnetism and in studies of sediment magnetization.

  14. Simultaneous demonstration of infectious pancreatic necrosis virus (IPNV) and Flavobacterium psychrophilum in paraffin-embedded specimens of rainbow trout Oncorhynchus mykiss fry by use of paired immunohistochemistry

    DEFF Research Database (Denmark)

    Evensen, Ø.; Lorenzen, Ellen

    1997-01-01

    'persistent' cases of RTFS have been observed concomitant with IPNV. Cultivation alone might not be sufficient for evaluation of the disease situation as both pathogens can be cultivated from fish that do not show any clinical signs of disease. In such cases it may be difficult to decide which pathogen should...... be considered the primary cause of the mortality observed. Further, it may be difficult to cultivate the bacterium in later stages of the disease or from dead fish that have been transported without cooling. In the case of (suspected) double infections it is therefore suggested that immunohistochemistry...... by immunohistochemistry and supported by cultivation of the 2 pathogens. The general finding was that single cells of the exocrine pancreas were positive for the virus, whereas bacteria were mainly demonstrated in the interstitial tissue surrounding the pancreatic islets. In some endothelial cells of the head kidney...

  15. Treatment of common warts with the immune stimulant Propionium bacterium parvum Tratamento das verrugas vulgares com o imunoestimulante Propionium bacterium parvum

    OpenAIRE

    Nilton Nasser

    2012-01-01

    BACKGROUND: Warts are epithelial proliferations in the skin and mucous membrane caused by various types of HPV. They can decrease spontaneously or increase in size and number according to the patient's immune status. The Propionium bacterium parvum is a strong immune stimulant and immune modulator and has important effects in the immune system and it is able to produce antibodies in the skin. OBJECTIVE: To show the efficacy of the Propionium bacterium parvum in saline solution in the treatmen...

  16. Draft Genome Sequence of Ensifer adhaerens M78, a Mineral-Weathering Bacterium Isolated from Soil.

    Science.gov (United States)

    Wang, Yuanli; Chen, Wei; He, Linyan; Wang, Qi; Sheng, Xia-Fang

    2016-01-01

    Ensifer adhaerens M78, a bacterium isolated from soil, can weather potash feldspar and release Fe, Si, and Al from rock under nutrient-poor conditions. Here, we report the draft genome sequence of strain M78, which may facilitate a better understanding of the molecular mechanism involved in mineral weathering by the bacterium. PMID:27609930

  17. Draft Genome Sequence of Ensifer adhaerens M78, a Mineral-Weathering Bacterium Isolated from Soil.

    Science.gov (United States)

    Wang, Yuanli; Chen, Wei; He, Linyan; Wang, Qi; Sheng, Xia-Fang

    2016-01-01

    Ensifer adhaerens M78, a bacterium isolated from soil, can weather potash feldspar and release Fe, Si, and Al from rock under nutrient-poor conditions. Here, we report the draft genome sequence of strain M78, which may facilitate a better understanding of the molecular mechanism involved in mineral weathering by the bacterium.

  18. Dense populations of a giant sulfur bacterium in Namibian shelf sediments

    DEFF Research Database (Denmark)

    Schulz, HN; Brinkhoff, T.; Ferdelman, TG;

    1999-01-01

    A previously unknown giant sulfur bacterium is abundant in sediments underlying the oxygen minimum zone of the Benguela Current upwelling system. The bacterium has a spherical cell that exceeds by up to 100-fold the biovolume of the largest known prokaryotes. On the basis of 16S ribosomal DNA...

  19. Burkholderia phytofirmans sp. nov., a novel plant-associated bacterium with plant-beneficial properties

    NARCIS (Netherlands)

    Sessitsch, A; Coenye, T; Sturz, AV; Vandamme, P; Barka, EA; Salles, JF; Van Elsas, JD; Faure, D; Reiter, B; Glick, BR; Wang-Pruski, G; Nowak, J

    2005-01-01

    A Gram-negative, non-sporulating, rod-shaped, motile bacterium, with a single polar flagellum, designated strain PsJNT, was isolated from surface-sterilized onion roots. This isolate proved to be a highly effective plant-beneficial bacterium, and was able to establish rhizosphere and endophytic popu

  20. Algicidal lactones from the marine Roseobacter clade bacterium Ruegeria pomeroyi

    Directory of Open Access Journals (Sweden)

    Ramona Riclea

    2012-06-01

    Full Text Available Volatiles released by the marine Roseobacter clade bacterium Rugeria pomeroyi were collected by use of a closed-loop stripping headspace apparatus (CLSA and analysed by GC–MS. Several lactones were found for which structural proposals were derived from their mass spectra and unambiguously verified by the synthesis of reference compounds. An enantioselective synthesis of two exemplary lactones was performed to establish the enantiomeric compositions of the natural products by enantioselective GC–MS analyses. The lactones were subjected to biotests to investigate their activity against several bacteria, fungi, and algae. A specific algicidal activity was observed that may be important in the interaction between the bacteria and their algal hosts in fading algal blooms.

  1. A bacterium that degrades and assimilates poly(ethylene terephthalate).

    Science.gov (United States)

    Yoshida, Shosuke; Hiraga, Kazumi; Takehana, Toshihiko; Taniguchi, Ikuo; Yamaji, Hironao; Maeda, Yasuhito; Toyohara, Kiyotsuna; Miyamoto, Kenji; Kimura, Yoshiharu; Oda, Kohei

    2016-03-11

    Poly(ethylene terephthalate) (PET) is used extensively worldwide in plastic products, and its accumulation in the environment has become a global concern. Because the ability to enzymatically degrade PET has been thought to be limited to a few fungal species, biodegradation is not yet a viable remediation or recycling strategy. By screening natural microbial communities exposed to PET in the environment, we isolated a novel bacterium, Ideonella sakaiensis 201-F6, that is able to use PET as its major energy and carbon source. When grown on PET, this strain produces two enzymes capable of hydrolyzing PET and the reaction intermediate, mono(2-hydroxyethyl) terephthalic acid. Both enzymes are required to enzymatically convert PET efficiently into its two environmentally benign monomers, terephthalic acid and ethylene glycol.

  2. Characterisation of an unusual bacterium isolated from genital ulcers.

    Science.gov (United States)

    Ursi, J P; van Dyck, E; Ballard, R C; Jacob, W; Piot, P; Meheus, A Z

    1982-02-01

    The preliminary characterisation of an unusual gram-negative bacillus isolated from genital ulcers in Swaziland is reported. Like Haemophilus ducreyi, it is an oxidase positive, nitrate-reductase-positive gram-negative rod that forms streptobacillary chains in some circumstances; it was therefore called the "ducreyi-like bacterium" (DLB). Distinguishing features of DLB are production of alpha-haemolysis on horse-blood agar, stimulation of growth by a microaerophilic atmosphere and by a factor produced by Staphylococcus aureus, a strongly positive porphyrin test, and a remarkable ability to undergo autolysis. DLB had a guanine + cytosine value of c. 50 mole% but it cannot be classified, even at the genus level, until more taxonomic data are obtained.

  3. Genome analysis of the Anerobic Thermohalophilic bacterium Halothermothrix orenii

    Energy Technology Data Exchange (ETDEWEB)

    Mavromatis, Konstantinos; Ivanova, Natalia; Anderson, Iain; Lykidis, Athanasios; Hooper, Sean D.; Sun, Hui; Kunin, Victor; Lapidus, Alla; Hugenholtz, Philip; Patel, Bharat; Kyrpides, Nikos C.

    2008-11-03

    Halothermothirx orenii is a strictly anaerobic thermohalophilic bacterium isolated from sediment of a Tunisian salt lake. It belongs to the order Halanaerobiales in the phylum Firmicutes. The complete sequence revealed that the genome consists of one circular chromosome of 2578146 bps encoding 2451 predicted genes. This is the first genome sequence of an organism belonging to the Haloanaerobiales. Features of both Gram positive and Gram negative bacteria were identified with the presence of both a sporulating mechanism typical of Firmicutes and a characteristic Gram negative lipopolysaccharide being the most prominent. Protein sequence analyses and metabolic reconstruction reveal a unique combination of strategies for thermophilic and halophilic adaptation. H. orenii can serve as a model organism for the study of the evolution of the Gram negative phenotype as well as the adaptation under thermohalophilic conditions and the development of biotechnological applications under conditions that require high temperatures and high salt concentrations.

  4. A bacterium that degrades and assimilates poly(ethylene terephthalate).

    Science.gov (United States)

    Yoshida, Shosuke; Hiraga, Kazumi; Takehana, Toshihiko; Taniguchi, Ikuo; Yamaji, Hironao; Maeda, Yasuhito; Toyohara, Kiyotsuna; Miyamoto, Kenji; Kimura, Yoshiharu; Oda, Kohei

    2016-03-11

    Poly(ethylene terephthalate) (PET) is used extensively worldwide in plastic products, and its accumulation in the environment has become a global concern. Because the ability to enzymatically degrade PET has been thought to be limited to a few fungal species, biodegradation is not yet a viable remediation or recycling strategy. By screening natural microbial communities exposed to PET in the environment, we isolated a novel bacterium, Ideonella sakaiensis 201-F6, that is able to use PET as its major energy and carbon source. When grown on PET, this strain produces two enzymes capable of hydrolyzing PET and the reaction intermediate, mono(2-hydroxyethyl) terephthalic acid. Both enzymes are required to enzymatically convert PET efficiently into its two environmentally benign monomers, terephthalic acid and ethylene glycol. PMID:26965627

  5. Isolation of a bacterium that reductively dechlorinates tetrachloroethene to ethene

    Energy Technology Data Exchange (ETDEWEB)

    Maymo-Gatell, X.; Chien, Yueh-tyng; Zinder, S.H. [Cornell Univ., Ithaca, NY (United States)] [and others

    1997-06-06

    Tetrachloroethene is a prominent groundwater pollutant that can be reductively dechlorinated by mixed anaerobic microbial populations to the nontoxic product ethene. Strain 195, a coccoid bacterium that dechlorinates tetrachlorethene to ethene, was isolated and characterized. Growth of strain 195 with H{sub 2} and tetrachloroethene as the electron donor and acceptor pair required extracts from mixed microbial cultures. Growth of strain 195 was resistant to ampicillin and vancomycin; its cell wall did not react with a peptidoglycan-specific lectin and its ultrastructure resembled S-layers of Archaea. Analysis of the 16S ribosomal DNA sequence of strain 195 indicated that it is a eubacterium without close affiliation to any known groups. 24 refs., 4 figs., 1 tab.

  6. Biological characteristics of marine bacterium S - 9801 strain and its culture conditions of pigment production

    Institute of Scientific and Technical Information of China (English)

    田黎; 何培青; 武洪庆; 温占波; 刘晨临; 李光友

    2002-01-01

    Strain of Flavobacterium sp. (S- 9801), was screened from 207 strains of marine bacteria isolated from the Bohai Sea continental shelf and the Zhujiang Estuary, for its red pigment production. The biological characteristics of strain S- 9801 and culture conditions of pigment production have been checked out in this study. The color of the bacterial colony on 2216E medium was from coccineus to rose bengal. Optimum culture conditions were sodium chloride concentration(g/dm3), 10~30; pH,3~8; temperature, 25~28℃; tryptone and yeast extract as nitrogen sources and gluccse as carbon source. Under optimum conditions, pigment accumulation started after 12 h, reaching a maximum rate of synthesis at 36 h.

  7. Treatment of common warts with the immune stimulant Propionium bacterium parvum Tratamento das verrugas vulgares com o imunoestimulante Propionium bacterium parvum

    Directory of Open Access Journals (Sweden)

    Nilton Nasser

    2012-08-01

    Full Text Available BACKGROUND: Warts are epithelial proliferations in the skin and mucous membrane caused by various types of HPV. They can decrease spontaneously or increase in size and number according to the patient's immune status. The Propionium bacterium parvum is a strong immune stimulant and immune modulator and has important effects in the immune system and it is able to produce antibodies in the skin. OBJECTIVE: To show the efficacy of the Propionium bacterium parvum in saline solution in the treatment of skin warts. METHODS: A randomized double-blind study. Twenty patients with multiple warts were divided into two groups: one received 0,1ml intradermal injection of placebo solution in just one of the warts and the other received 0,1 ml of saline solution of Propionium bacterium parvum, one dose a month, for 3 to 5 months. RESULTS: Among the 20 patients who participated in the study, ten received the placebo and ten received the saline solution with Propionium bacterium parvum. In 9 patients treated with the Propionium bacterium parvum solution the warts disappeared without scars and in 1 patient it decreased in size. In 9 patients who received the placebo no change to the warts was observed and in 1 it decreased in size. CONCLUSIONS: The immune modulator and immune stimulant Propionium bacterium parvum produced antibodies in the skin which destroyed the warts without scars, with statistically significant results (PFUNDAMENTOS: Verrugas são proliferações epiteliais na pele e mucosas causadas por diversos tipos de HPV. Elas podem involuir espontaneameme ou aumentar em número e tamanho de acordo com estado imunitário do paciente. O Propionium bacterium parvum é urn potente imunoestimulador e imunomodulador e tem efeitos importantes no sistema imune e é capaz de produzir anticorpos na pele. OBJETIVO: Mostrar a eficácia do Propionium bacterium parvum diluído em solução salina no tratamento de verrugas cutâneas. MÊTODOS: Estudo duplo

  8. Tracing the run-flip motion of an individual bacterium

    Science.gov (United States)

    Liu, Bin; Morse, Michael; Tang, Jay; Powers, Thomas; Breuer, Kenneth S.

    2012-11-01

    We have developed a digital 3D tracking microscope in which the microscope stage follows the motion of an individual motile microorganism so that the target remains focused at the center of the view-field. The tracking mechanism is achieved by a high-speed feedback control through real-time image analysis and the trace of the microorganism is recorded with submicron accuracy. We apply this tracking microscope to a study of the motion of an individual Caulobacter crescentus, a bacterium that moves up to 100 microns (or 50 body lengths) per second and reverses its direction of motion occasionally by switching the rotation direction of its single helical flagellum. By tracking the motion of a single cell over many seconds, we show how a flip event occurs with submicron resolution and how the speed of a single cell varies over time and with the rotational rate of the flagellum. We also present statistics for the run-reverse dynamics of an ensemble of cells.

  9. Bioconversion of methane to lactate by an obligate methanotrophic bacterium

    Science.gov (United States)

    Henard, Calvin A.; Smith, Holly; Dowe, Nancy; Kalyuzhnaya, Marina G.; Pienkos, Philip T.; Guarnieri, Michael T.

    2016-01-01

    Methane is the second most abundant greenhouse gas (GHG), with nearly 60% of emissions derived from anthropogenic sources. Microbial conversion of methane to fuels and value-added chemicals offers a means to reduce GHG emissions, while also valorizing this otherwise squandered high-volume, high-energy gas. However, to date, advances in methane biocatalysis have been constrained by the low-productivity and limited genetic tractability of natural methane-consuming microbes. Here, leveraging recent identification of a novel, tractable methanotrophic bacterium, Methylomicrobium buryatense, we demonstrate microbial biocatalysis of methane to lactate, an industrial platform chemical. Heterologous overexpression of a Lactobacillus helveticus L-lactate dehydrogenase in M. buryatense resulted in an initial titer of 0.06 g lactate/L from methane. Cultivation in a 5 L continuously stirred tank bioreactor enabled production of 0.8 g lactate/L, representing a 13-fold improvement compared to the initial titer. The yields (0.05 g lactate/g methane) and productivity (0.008 g lactate/L/h) indicate the need and opportunity for future strain improvement. Additionally, real-time analysis of methane utilization implicated gas-to-liquid transfer and/or microbial methane consumption as process limitations. This work opens the door to develop an array of methanotrophic bacterial strain-engineering strategies currently employed for biocatalytic sugar upgrading to “green” chemicals and fuels. PMID:26902345

  10. Denitrification characteristics of a marine origin psychrophilic aerobic denitrifying bacterium.

    Science.gov (United States)

    Zheng, Haiyan; Liu, Ying; Sun, Guangdong; Gao, Xiyan; Zhang, Qingling; Liu, Zhipei

    2011-01-01

    A psychrophilic aerobic denitrifying bacterium, strain S1-1, was isolated from a biological aerated filter conducted for treatment of recirculating water in a marine aquaculture system. Strain S1-1 was preliminarily identified as Psychrobacter sp. based on the analysis of its 16S rRNA gene sequence, which showed 100% sequence similarity to that of Psychrobacter sp. TSBY-70. Strain S1-1 grew well either in high nitrate or high nitrite conditions with a removal of 100% nitrate or 63.50% nitrite, and the total nitrogen removal rates could reach to 46.48% and 31.89%, respectively. The results indicated that nitrate was mainly reduced in its logarithmic growth phase with a very low level accumulation of nitrite, suggesting that the aerobic denitrification process of strain S1-1 occurred mainly in this phase. The GC-MS results showed that N2O was formed as the major intermediate during the aerobic denitrifying process of strain S1-1. Finally, factors affecting the growth of strain S1-1 and its aerobic denitrifying ability were also investigated. Results showed that the optimum aerobic denitrification conditions for strain S1-1 were sodium succinate as carbon source, C/N ratio15, salinity 10 g/L NaCl, incubation temperature 20 degrees C and initial pH 6.5. PMID:22432315

  11. Denitrification characteristics of a marine origin psychrophilic aerobic denitrifying bacterium

    Institute of Scientific and Technical Information of China (English)

    Haiyan Zheng; Ying Liu; Guangdong Sun; Xiyan Gao; Qingling Zhang; Zhipei Liu

    2011-01-01

    A psychrophilic aerobic denitrifying bacterium,strain S1-1,was isolated from a biological aerated filter conducted for treatment of recirculating water in a marine aquaculture system.Strain S1-1 was preliminarily identified as Psychrobacter sp.based on the analysis of its 16S rRNA gene sequence,which showed 100% sequence similarity to that of Psychrobacter sp.TSBY-70.Strain S 1-1 grew well either in high nitrate or high nitrite conditions with a removal of 100% nitrate or 63.50% nitrite,and the total nitrogen removal rates could reach to 46.48% and 31.89%,respectively.The results indicated that nitrate was mainly reduced in its logarithmic growth phase with a very low leve 1 accumulation of nitrite,suggesting that the aerobic denitrification process of strain S l-1 occurred mainly in this phase.The GC-MS results showed that N2O was formed as the major intermediate during the aerobic denitrifying process of strain S1-1.Finally,factors affecting the growth of strain Sl-1 and its aerobic denitrifying ability were also investigated.Results showed that the optimum aerobic denitrification conditions for strain S1-1 were sodium succinate as carbon source,C/N ratio15,salinity 10 g/L NaCl,incubation temperature 20℃ and initial pH 6.5.

  12. Presence of an unusual methanogenic bacterium in coal gasification waste

    Energy Technology Data Exchange (ETDEWEB)

    Tomei, F.A.; Rouse, D.; Maki, J.S.; Mitchell, R.

    1988-12-01

    Methanogenic bacteria growing on a pilot-scale, anaerobic filter processing coal gasification waste were enriched in a mineral salts medium containing hydrogen and acetate as potential energy sources. Transfer of the enrichments to methanol medium resulted in the initial growth of a strain of Methanosarcina barkeri, but eventually small cocci became dominant. The cocci growing on methanol produced methane and exhibited the typical fluorescence of methanogenic bacteria. They grew in the presence of the cell wall synthesis-inhibiting antibiotics D-cycloserine, fosfomycin, penicillin G, and vancomycin as well as in the presence of kanamycin, an inhibitor of protein synthesis in eubacteria. The optimal growth temperature was 37 degrees C, and the doubling time was 7.5 h. The strain lysed after reaching stationary phase. The bacterium grew poorly with hydrogen as the energy source and failed to grow on acetate. Morphologically, the coccus shared similarities with Methanosarcina sp. Cells were 1 ..mu..m wide, exhibited the typical thick cell wall and cross-wall formation, and formed tetrads. Packets and cysts were not formed. 62 refs., 4 figs.

  13. Electromicrobiology of Dissimilatory Sulfur Reducing Bacterium Desulfuromonas acetexigens

    KAUST Repository

    Bin Bandar, Khaled

    2014-12-01

    Bioelectrochmical systems (BES) are engineered electrochemical devices that harness hidden chemical energy of the wastewater in to the form of electricity or hydrogen. Unique microbial communities enrich in these systems for oxidation of organic matter as well as transfer of resulted electron to anode, known them as “electricigens” communities. Exploring novel electricigenesis microbial communities in the nature and understanding their electromicrobiology is one the important aspect for BES systems scale up. Herein, we report first time the electricigenesis property of an anaerobic, fresh water sediment, sulfur reducing bacterium Desulfuromona acetexigens. The electrochemical behavior of D. acetexigens biofilms grown on graphite-rod electrodes in batch-fed mode under an applied potential was investigated with traditional electroanalytical tools, and correlate the electron transfer from biofilms to electrode with a model electricigen Geobacter sulfurreducens electrochemical behavior. Research findings suggest that D. acetexigens has the ability to use electrode as electron acceptor in BES systems through establishing the direct contact with anode by expressing the membrane bound redox proteins, but not due to the secretion of soluble redox mediators. Preliminary results revealed that D. acetexigens express three distinct redox proteins in their membranes for turnover of the electrons from biofilm to electrode, and the 4 whole electricigenesis process observed to be unique in the D. acetexigens compared to that of well-studied model organism G. sulfurreducens.

  14. Bioconversion of methane to lactate by an obligate methanotrophic bacterium.

    Science.gov (United States)

    Henard, Calvin A; Smith, Holly; Dowe, Nancy; Kalyuzhnaya, Marina G; Pienkos, Philip T; Guarnieri, Michael T

    2016-01-01

    Methane is the second most abundant greenhouse gas (GHG), with nearly 60% of emissions derived from anthropogenic sources. Microbial conversion of methane to fuels and value-added chemicals offers a means to reduce GHG emissions, while also valorizing this otherwise squandered high-volume, high-energy gas. However, to date, advances in methane biocatalysis have been constrained by the low-productivity and limited genetic tractability of natural methane-consuming microbes. Here, leveraging recent identification of a novel, tractable methanotrophic bacterium, Methylomicrobium buryatense, we demonstrate microbial biocatalysis of methane to lactate, an industrial platform chemical. Heterologous overexpression of a Lactobacillus helveticus L-lactate dehydrogenase in M. buryatense resulted in an initial titer of 0.06 g lactate/L from methane. Cultivation in a 5 L continuously stirred tank bioreactor enabled production of 0.8 g lactate/L, representing a 13-fold improvement compared to the initial titer. The yields (0.05 g lactate/g methane) and productivity (0.008 g lactate/L/h) indicate the need and opportunity for future strain improvement. Additionally, real-time analysis of methane utilization implicated gas-to-liquid transfer and/or microbial methane consumption as process limitations. This work opens the door to develop an array of methanotrophic bacterial strain-engineering strategies currently employed for biocatalytic sugar upgrading to "green" chemicals and fuels. PMID:26902345

  15. Pandoraea sp. RB-44, A Novel Quorum Sensing Soil Bacterium

    Directory of Open Access Journals (Sweden)

    Robson Ee Han-Jen

    2013-10-01

    Full Text Available Proteobacteria are known to communicate via signaling molecules and this process is known as quorum sensing. The most commonly studied quorum sensing molecules are N-acylhomoserine lactones (AHLs that consists of a homoserine lactone moiety and an N-acyl side chain with various chain lengths and degrees of saturation at the C-3 position. We have isolated a bacterium, RB-44, from a site which was formally a landfill dumping ground. Using matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF mass spectrometry analysis, this isolate was identified as a Pandoraea sp.which was then screened for AHL production using biosensors which indicated its quorum sensing properties. To identify the AHL profile of Pandoraea sp. RB-44, we used high resolution tandem mass spectrometry confirming that this isolate produced N-octanoylhomoserine lactone (C8-HSL. To the best of our knowledge, this is the first report that showed quorum sensing activity exhibited by Pandoraea sp. Our data add Pandoraea sp. to the growing number of bacteria that possess QS systems.

  16. Carbohydrate utilization patterns for the extremely thermophilic bacterium Caldicellulosiruptor saccharolyticus reveal broad growth substrate preferences

    NARCIS (Netherlands)

    Vanfossen, A.L.; Verhaart, M.R.A.; Kengen, S.W.M.; Kelly, R.M.

    2009-01-01

    Co-utilization of hexoses and pentoses derived from lignocellulose is an attractive trait in microorganisms considered for consolidated biomass processing to biofuels. This issue was examined for the H2-producing, extremely thermophilic bacterium Caldicellulosiruptor saccharolyticus growing on indiv

  17. SIMULTANEOUS PHOTOTROPHIC AND CHEMOTROPIC GROWTH IN THE PURPLE SULFUR BACTERIUM THIOCAPSA-ROSEOPERSICINA M1

    NARCIS (Netherlands)

    SCHAUB, BEM; VANGEMERDEN, H

    1994-01-01

    The anoxygenic phototrophic purple sulfur bacterium Thiocapsa roseopersicina was grown in illuminated continuous cultures with thiosulfate as growth limiting substrate. Aeration resulted in completely colorless cells growing chemotrophically, whereafter the conditions were changed to a 23 h oxic/1 h

  18. Isolation and characterization of Caldicellulosiruptor lactoaceticus sp. nov., an extremely thermophilic, cellulolytic, anaerobic bacterium

    DEFF Research Database (Denmark)

    Mladenovska, Zuzana; Mathrani, Indra M.; Ahring, Birgitte Kiær

    1995-01-01

    and ethanol occurred as minor fermentation products. Only a restricted number of carbon sources (cellulose, xylan, starch, pectin, cellobiose, xylose, maltose and lactose) were used as substrates. During growth on Avicel, the bacterium produced free cellulases with carboxymethylcellulase and avicelase...

  19. Turnover of dimethylsulfoniopropionate (DMSP) by the purple sulfur bacterium Thiocapsa roseopersicina M11 : Ecological implications

    NARCIS (Netherlands)

    Jonkers, HM; van Gemerden, H

    1998-01-01

    The use of dimethylsulfoniopropionate (DMSP) by the anoxygenic phototrophic purple sulfur bacterium Thiocapsa roseopersicina M11 under different environmental conditions was studied. Under anoxic/light conditions DMSP cleavage occurred both at low and intermediate salinities but at different growth

  20. Genome Sequence of the Haloalkaliphilic Methanotrophic Bacterium Methylomicrobium alcaliphilum 20Z

    OpenAIRE

    Vuilleumier, Stéphane; Khmelenina, Valentina N; Bringel, Françoise; Reshetnikov, Alexandr S.; Lajus, Aurélie; Mangenot, Sophie; Rouy, Zoé; Op Den Camp, Huub J M; Jetten, Mike S. M.; DiSpirito, Alan A.; Dunfield, Peter; Klotz, Martin G.; Semrau, Jeremy D.; Stein, Lisa Y.; Barbe, Valérie

    2012-01-01

    Methylomicrobium strains are widespread in saline environments. Here, we report the complete genome sequence of Methylomicrobium alcaliphilum 20Z, a haloalkaliphilic methanotrophic bacterium, which will provide the basis for detailed characterization of the core pathways of both single-carbon metabolism and responses to osmotic and high-pH stresses. Final assembly of the genome sequence revealed that this bacterium contains a 128-kb plasmid, making M. alcaliphilum 20Z the first methanotrophic...

  1. Effect of alginic acid decomposing bacterium on the growth of Laminaria japonica (Phaeophyceae)

    Institute of Scientific and Technical Information of China (English)

    WANG You; TANG Xue-xi; YANG Zhen; YU Zhi-ming

    2006-01-01

    We collected the diseased blades of Laminaria japonica from Yantai Sea Farm from October to December 2002, and the alginic acid decomposing bacterium on the diseased blade was isolated and purified, and was identified as Alteromonas espejiana. This bacterium was applied as the causative pathogen to infect the blades of L. japonica under laboratory conditions. The aim of the present study was to identify the effects of the bacterium on the growth of L. japonica, and to find the possibly effective mechanism. Results showed that: (1)The blades of L.japonica exhibited symptoms of lesion,bleaching and deterioration when infected by the bacterium,and their growth and photosynthesis were dramatically suppressed. At the same time, the reactive oxygen species (ROS) generation enhanced obviously, and the relative membrane permeability increased significantly. The contents of malonaldehyde (MDA) and free fatty acid in the microsomol membrane greatly elevated, but the phospholipid content decreased. Result suggested an obvious peroxidation and deesterrification in the blades of L. japonica when infected by the bacterium. (2) The simultaneous assay on the antioxidant enzyme activities demonstrated that superoxide dismutase (SOD) and catalase (CAT) increased greatly when infected by the bacterium, but glutathione peroxidase (Gpx) and ascorbate peroxidase (APX) did not exhibit active responses to the bacterium throughout the experiment. (3) The histomorphological observations gave a distinctive evidence of the severity of the lesions as well as the relative abundance in the bacterial population on the blades after infection. The bacterium firstly invaded into the endodermis of L. japonica and gathered around there, and then resulted in the membrane damage, cells corruption and ultimately, the death of L.japonica.

  2. Draft Genome Sequence of a Dyella-Like Bacterium from the Planthopper Hyalesthes obsoletus.

    Science.gov (United States)

    Lahav, Tamar; Zchori-Fein, Einat; Naor, Vered; Freilich, Shiri; Iasur-Kruh, Lilach

    2016-01-01

    We report here the draft genome sequence of a Dyella-like bacterium (DLB) isolated from Hyalesthes obsoletus, the insect vector of the uncultivable mollicute bacterium "Candidatus Phytoplasma." This isolate inhibits Spiroplasma melliferum, a cultivable mollicute. The draft genome of DLB consists of 4,196,214 bp, with a 68.6% G+C content, and 3,757 genes were predicted. PMID:27445378

  3. Draft Genome Sequence of DLB, a Dyella-Like Bacterium from the Planthopper Hyalesthes obsoletus

    Science.gov (United States)

    Lahav, Tamar; Zchori-Fein, Einat; Naor, Vered; Freilich, Shiri

    2016-01-01

    We report here the draft genome sequence of a Dyella-like bacterium (DLB) isolated from Hyalesthes obsoletus, the insect vector of the uncultivable mollicute bacterium “Candidatus Phytoplasma.” This isolate inhibits Spiroplasma melliferum, a cultivable mollicute. The draft genome of DLB consists of 4,196,214 bp, with a 68.6% G+C content, and 3,757 genes were predicted. PMID:27445378

  4. Biosynthesis Of Gold Nanoparticles By Marine Purple Non Sulphur Bacterium, Rhodopseudomonas Sp.

    OpenAIRE

    Abirami. G; Asmathunisha. N; Kathiresan. K

    2013-01-01

    This paper describes for the first time that an anaerobic marine bacterium is capable of producing gold nanoparticles. A marine purple non-sulphur bacterium was isolated from mangrove sediment and identified as Rhodopseudomonas sp. . The bacterial culture was tested for the synthesis of gold nanoparticles by using aqueous HAuCl4 solution as substrate in darkness. The gold nanoparticles synthesized were found to be of cubical structure in the size range of 10–20 nm.

  5. Carbonate biomineralization induced by soil bacterium Bacillus megaterium

    Science.gov (United States)

    Lian, Bin; Hu, Qiaona; Chen, Jun; Ji, Junfeng; Teng, H. Henry

    2006-11-01

    Biogenic carbonates spawned from microbial activities are common occurrences in soils. Here, we investigate the carbonate biomineralization mediated by the bacterium Bacillus megaterium, a dominant strain separated from a loess profile in China. Upon completing bacterial cultivation, the ensuring products are centrifuged, and the resultant supernatant and the concentrated bacterial sludge as well as the un-separated culture are added separately into a Ca-CO 3 containing solution for crystallization experiments. Results of XRD and SEM analysis indicate that calcite is the dominant mineral phase formed when the bacteria are present. When the supernatant alone is used, however, a significant portion of vaterite is also precipitated. Experimental results further reveal that the bacteria have a strong tendency to colonize the center area of the calcite {1 0 1¯ 4} faces. Observed crystal morphology suggests that the bacterial colony may promote the growth normal to each individual {1 0 1¯ 4} face of calcite when the cell concentration is high, but may retard it or even cause dissolution of the immediate substrate surfaces when the concentration is low. SEM images taken at earlier stages of the crystallization experiments demonstrate the nucleation of calcite on the bacterial cell walls but do not show obvious morphological changes on the nanometer- to submicron-sized nuclei. δ 13C measurements unveil that the crystals grown in the presence of bacteria are further enriched in the heavy carbon isotope, implying that the bacterial metabolism may not be the carbon sources for the mineralization. Based upon these findings, we propose a mechanism for the B. megaterium mediated calcite mineralization and conclude that the whole process involves epi- and inter-cellular growth in the local microenvironments whose conditions may be controlled by cell sequestration and proton pumping during bacterial respiration.

  6. Metabolic evolution of a deep-branching hyperthermophilic chemoautotrophic bacterium.

    Science.gov (United States)

    Braakman, Rogier; Smith, Eric

    2014-01-01

    Aquifex aeolicus is a deep-branching hyperthermophilic chemoautotrophic bacterium restricted to hydrothermal vents and hot springs. These characteristics make it an excellent model system for studying the early evolution of metabolism. Here we present the whole-genome metabolic network of this organism and examine in detail the driving forces that have shaped it. We make extensive use of phylometabolic analysis, a method we recently introduced that generates trees of metabolic phenotypes by integrating phylogenetic and metabolic constraints. We reconstruct the evolution of a range of metabolic sub-systems, including the reductive citric acid (rTCA) cycle, as well as the biosynthesis and functional roles of several amino acids and cofactors. We show that A. aeolicus uses the reconstructed ancestral pathways within many of these sub-systems, and highlight how the evolutionary interconnections between sub-systems facilitated several key innovations. Our analyses further highlight three general classes of driving forces in metabolic evolution. One is the duplication and divergence of genes for enzymes as these progress from lower to higher substrate specificity, improving the kinetics of certain sub-systems. A second is the kinetic optimization of established pathways through fusion of enzymes, or their organization into larger complexes. The third is the minimization of the ATP unit cost to synthesize biomass, improving thermodynamic efficiency. Quantifying the distribution of these classes of innovations across metabolic sub-systems and across the tree of life will allow us to assess how a tradeoff between maximizing growth rate and growth efficiency has shaped the long-term metabolic evolution of the biosphere. PMID:24516572

  7. Interaction of Cadmium With the Aerobic Bacterium Pseudomonas Mendocina

    Science.gov (United States)

    Schramm, P. J.; Haack, E. A.; Maurice, P. A.

    2006-05-01

    The fate of toxic metals in the environment can be heavily influenced by interaction with bacteria in the vadose zone. This research focuses on the interactions of cadmium with the strict aerobe Pseudomonas mendocina. P. mendocina is a gram-negative bacterium that has shown potential in the bioremediation of recalcitrant organic compounds. Cadmium is a common environmental contaminant of wide-spread ecological consequence. In batch experiments P. mendocina shows typical bacterial growth curves, with an initial lag phase followed by an exponential phase and a stationary to death phase; concomitant with growth was an increase in pH from initial values of 7 to final values at 96 hours of 8.8. Cd both delays the onset of the exponential phase and decreases the maximum population size, as quantified by optical density and microscopic cell counts (DAPI). The total amount of Cd removed from solution increases over time, as does the amount of Cd removed from solution normalized per bacterial cell. Images obtained with transmission electron microscopy (TEM) showed the production of a cadmium, phosphorus, and iron containing precipitate that was similar in form and composition to precipitates formed abiotically at elevated pH. However, by late stationary phase, the precipitate had been re-dissolved, perhaps by biotic processes in order to obtain Fe. Stressed conditions are suggested by TEM images showing the formation of pili, or nanowires, when 20ppm Cd was present and a marked decrease in exopolysaccharide and biofilm material in comparison to control cells (no cadmium added).

  8. Metabolic evolution of a deep-branching hyperthermophilic chemoautotrophic bacterium.

    Directory of Open Access Journals (Sweden)

    Rogier Braakman

    Full Text Available Aquifex aeolicus is a deep-branching hyperthermophilic chemoautotrophic bacterium restricted to hydrothermal vents and hot springs. These characteristics make it an excellent model system for studying the early evolution of metabolism. Here we present the whole-genome metabolic network of this organism and examine in detail the driving forces that have shaped it. We make extensive use of phylometabolic analysis, a method we recently introduced that generates trees of metabolic phenotypes by integrating phylogenetic and metabolic constraints. We reconstruct the evolution of a range of metabolic sub-systems, including the reductive citric acid (rTCA cycle, as well as the biosynthesis and functional roles of several amino acids and cofactors. We show that A. aeolicus uses the reconstructed ancestral pathways within many of these sub-systems, and highlight how the evolutionary interconnections between sub-systems facilitated several key innovations. Our analyses further highlight three general classes of driving forces in metabolic evolution. One is the duplication and divergence of genes for enzymes as these progress from lower to higher substrate specificity, improving the kinetics of certain sub-systems. A second is the kinetic optimization of established pathways through fusion of enzymes, or their organization into larger complexes. The third is the minimization of the ATP unit cost to synthesize biomass, improving thermodynamic efficiency. Quantifying the distribution of these classes of innovations across metabolic sub-systems and across the tree of life will allow us to assess how a tradeoff between maximizing growth rate and growth efficiency has shaped the long-term metabolic evolution of the biosphere.

  9. Regulation of Polyhydroxybutyrate Synthesis in the Soil Bacterium Bradyrhizobium diazoefficiens.

    Science.gov (United States)

    Quelas, J I; Mesa, S; Mongiardini, E J; Jendrossek, D; Lodeiro, A R

    2016-07-15

    Polyhydroxybutyrate (PHB) is a carbon and energy reserve polymer in various prokaryotic species. We determined that, when grown with mannitol as the sole carbon source, Bradyrhizobium diazoefficiens produces a homopolymer composed only of 3-hydroxybutyrate units (PHB). Conditions of oxygen limitation (such as microoxia, oxic stationary phase, and bacteroids inside legume nodules) were permissive for the synthesis of PHB, which was observed as cytoplasmic granules. To study the regulation of PHB synthesis, we generated mutations in the regulator gene phaR and the phasin genes phaP1 and phaP4 Under permissive conditions, mutation of phaR impaired PHB accumulation, and a phaP1 phaP4 double mutant produced more PHB than the wild type, which was accumulated in a single, large cytoplasmic granule. Moreover, PhaR negatively regulated the expression of phaP1 and phaP4 as well as the expression of phaA1 and phaA2 (encoding a 3-ketoacyl coenzyme A [CoA] thiolases), phaC1 and phaC2 (encoding PHB synthases), and fixK2 (encoding a cyclic AMP receptor protein [CRP]/fumarate and nitrate reductase regulator [FNR]-type transcription factor of genes for microoxic lifestyle). In addition to the depressed PHB cycling, phaR mutants accumulated more extracellular polysaccharides and promoted higher plant shoot dry weight and competitiveness for nodulation than the wild type, in contrast to the phaC1 mutant strain, which is defective in PHB synthesis. These results suggest that phaR not only regulates PHB granule formation by controlling the expression of phasins and biosynthetic enzymes but also acts as a global regulator of excess carbon allocation and symbiosis by controlling fixK2 IMPORTANCE: In this work, we investigated the regulation of polyhydroxybutyrate synthesis in the soybean-nodulating bacterium Bradyrhizobium diazoefficiens and its influence in bacterial free-living and symbiotic lifestyles. We uncovered a new interplay between the synthesis of this carbon reserve polymer

  10. A plant growth-promoting bacterium that decreases nickel toxicity in seedlings

    Energy Technology Data Exchange (ETDEWEB)

    Burd, G.I.; Dixon, D.G.; Glick, B.R. [Univ. of Waterloo, Ontario (Canada). Dept. of Biology

    1998-10-01

    A plant growth-promoting bacterium, Kluyvera ascorbata SUD165, that contained high levels of heavy metals was isolated from soil collected near Sudbury, Ontario, Canada. The bacterium was resistant to the toxic effects of Ni{sup 2+}, Pb{sup 2+}, Zn{sup 2+}, and CrO{sub 4}{sup {minus}}, produced a siderophore(s), and displayed 1-aminocyclopropane-1-carboxylic acid deaminase activity. Canola seeds inoculated with this bacterium and then grown under gnotobiotic conditions in the presence of high concentrations of nickel chloride were partially protected against nickel toxicity. In addition, protection by the bacterium against nickel toxicity was evident in pot experiments with canola and tomato seeds. The presence of K. ascorbata SUD165 had no measurable influence on the amount of nickel accumulated per milligram (dry weight) of either roots or shoots of canola plants. Therefore, the bacterial plant growth-promoting effect in the presence of nickel was probably not attributable to the reduction of nickel uptake by seedlings. Rather, it may reflect the ability of the bacterium to lower the level of stress ethylene induced by the nickel.

  11. Studies on the pathogenic bacterium of ulcer disease in Epinephelus awoara

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Studies were conducted to determine the cause of the acute mortality of cage-cultured Epinephelus awoara in the Tong'an Bay of Xiamen, China during the summer of 2002. Predominant bacteria strain TS-628 was isolated from the diseased grouper. The virulence test confirmed that TS-628 was the pathogenic bacterium. Biochemical characteristics of the isolates were determined using the automatic bacterial identification system and standard tube tests. To further confirm the identification, a 1 121 bp 16S rRNA gene sequence of the isolate was amplified by PCR, which had been deposited into Genbank (accession number: AY747308). According to the biochemical characteristics and by comparing the 16S rRNA gene homology of the isolate, the pathogenic bacterium was identified as Vibrio harveyi. Drug sensitivity tests showed that this pathogenic bacterium was sensitive to 16 antibacterials, especially to chloramphenicol and actinospectacin, but completely resistant to antibacterials likes vancomycin, penicillin, lincomycin, and so on.

  12. Complete Genome Sequence of a thermotolerant sporogenic lactic acid bacterium, Bacillus coagulans strain 36D1

    Energy Technology Data Exchange (ETDEWEB)

    Rhee, Mun Su [University of Florida, Gainesville; Moritz, Brelan E. [University of Florida, Gainesville; Xie, Gary [Los Alamos National Laboratory (LANL); Glavina Del Rio, Tijana [U.S. Department of Energy, Joint Genome Institute; Dalin, Eileen [U.S. Department of Energy, Joint Genome Institute; Tice, Hope [U.S. Department of Energy, Joint Genome Institute; Bruce, David [Los Alamos National Laboratory (LANL); Goodwin, Lynne A. [Los Alamos National Laboratory (LANL); Chertkov, Olga [Los Alamos National Laboratory (LANL); Brettin, Thomas S [ORNL; Han, Cliff [Los Alamos National Laboratory (LANL); Detter, J. Chris [U.S. Department of Energy, Joint Genome Institute; Pitluck, Sam [U.S. Department of Energy, Joint Genome Institute; Land, Miriam L [ORNL; Patel, Milind [University of Florida, Gainesville; Ou, Mark [University of Florida, Gainesville; Harbrucker, Roberta [University of Florida, Gainesville; Ingram, Lonnie O. [University of Florida; Shanmugam, Keelnathan T. [University of Florida

    2011-01-01

    Bacillus coagulans is a ubiquitous soil bacterium that grows at 50-55 C and pH 5.0 and fer- ments various sugars that constitute plant biomass to L (+)-lactic acid. The ability of this spo- rogenic lactic acid bacterium to grow at 50-55 C and pH 5.0 makes this organism an attrac- tive microbial biocatalyst for production of optically pure lactic acid at industrial scale not only from glucose derived from cellulose but also from xylose, a major constituent of hemi- cellulose. This bacterium is also considered as a potential probiotic. Complete genome se- quence of a representative strain, B. coagulans strain 36D1, is presented and discussed.

  13. Action of the Selenomorpholine Compounds on the Bacterium Growth by Microcalorimetry

    Institute of Scientific and Technical Information of China (English)

    李曦; 刘义; 等

    2002-01-01

    The action of β-(N-selenomorpholine) ethyl phenyl ketone hydrochloride and 4-(N-selenomorpholine)-2-butanone hydro-chloride on Escherichia coli and Staphylococcus aureus was studied by microcalorimetry,Differences in their capacities to affect the metabolism of this bacterium were observed.The kinetics shows that the selenomorpholine compounds had action on the metabolism process of Escherichia coli and Staphylococcus aureus.The rate constant (k) of the studied bacterium in the presence of the drugs are concentration-dependant.The growth rate constants decrease with an increase in the mass of the selenomorpholine compounds ,but their relationship is different.As deduced from the rate constant(k) of the studied bacterium(in log phase )and the half inhibitory concentration (IC50),the experimental results reveal that the studied selenomorpholine compounds all have good antibiotic activity and better antibacterial activity on Staphylcoccus aureus than on Escherichia coli.

  14. Action of the Selenomorpholine Compounds on the Bacterium Growth by Microcalorimetry

    Institute of Scientific and Technical Information of China (English)

    LI,Xi(李曦); LIU,Yi(刘义); WU,Jun(吴军); QU,Song-Sheng(屈松生)

    2002-01-01

    The action of β-(N-selenomorpholine) ethyl phenyl ketone hy drochloride and 4-(N-selenomorpholine)-2-butanone hydrochloride on Escherichia coli and Staphylococcus aureus was studied by microcalorimetry. Differences in their capacities to affect the metabolism of this bacterium were observed. The kinetics shows that the selenomorphline compounds had action on the metabolism process of Escherichia coli and Staphylococcus aureus. The rate constant (k) of the studied bacterium in the presence of the drugs are concentration-dependant. The growth rate constants decrease with an increase in the mass of the selenomorpholine compounds, but their relationship is different. As deduced from the rate constant (k) of the studied bacterium (in log phase) and the half inhibitory concentration (IC50), the experimental results reveal that the studied selenomorphline compounds all have good antibiotic activity and better antibacterial activity on Staphylococcus aureus than on Escherichia coli.

  15. Complete Genome Sequence of a thermotolerant sporogenic lactic acid bacterium, Bacillus coagulans strain 36D1

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Gary [Los Alamos National Laboratory (LANL); Dalin, Eileen [U.S. Department of Energy, Joint Genome Institute; Tice, Hope [U.S. Department of Energy, Joint Genome Institute; Chertkov, Olga [Los Alamos National Laboratory (LANL); Land, Miriam L [ORNL

    2011-01-01

    Bacillus coagulans is a ubiquitous soil bacterium that grows at 50-55 C and pH 5.0 and fer-ments various sugars that constitute plant biomass to L (+)-lactic acid. The ability of this sporogenic lactic acid bacterium to grow at 50-55 C and pH 5.0 makes this organism an attractive microbial biocatalyst for production of optically pure lactic acid at industrial scale not only from glucose derived from cellulose but also from xylose, a major constituent of hemi-cellulose. This bacterium is also considered as a potential probiotic. Complete genome squence of a representative strain, B. coagulans strain 36D1, is presented and discussed.

  16. Removal of corper(II) Ions from aqueous solution by a lactic acid bacterium

    OpenAIRE

    M. Yilmaz(Department of Physics, Gazi University, Ankara); T. Tay; M. Kivanc; H. Turk

    2010-01-01

    Enterococcus faecium, a lactic acid bacterium (LAB), was evaluated for its ability to remove copper(II) ions from water. The effects of the pH, contact time, initial concentration of copper(II) ions, and temperature on the biosorption rate and capacity were studied. The initial concentrations of copper(II) ions used to determine the maximum amount of biosorbed copper(II) ions onto lyophilised lactic acid bacterium varied from 25 mg L-1 to 500 mg L-1. Maximum biosorption capacities were attain...

  17. Sensitivity of the bacterium Bacillus Thuringiensis as an insect disease agent to gamma-rays

    International Nuclear Information System (INIS)

    The effect of gamma radiation on the viability of the entomopathogenic spore-forming bacterium, Bacillus thuringiensis, was tested. The different gamma doses varied much in their effect on such bacterium. All irradiated Bacillus suspensions with doses below 85 krad showed different degrees of inhibitory activity. However, bacterial suspensions irradiated at a dose of 90 krad. proved to promote spore germination. Changes in the physiological, and morphological characters of the irradiated Bacillus at these levels were detected. The new observed characters were induced at a particular dose level of 90 krad. These new characters are assumed to be due to genetic changes induced at this particular gamma dose

  18. Purification and Characterization of Haloalkaline, Organic Solvent Stable Xylanase from Newly Isolated Halophilic Bacterium-OKH

    OpenAIRE

    Sanghvi, Gaurav; Jivrajani, Mehul; Patel, Nirav; Jivrajani, Heta; Bhaskara, Govinal Badiger; Patel, Shivani

    2014-01-01

    A novel, alkali-tolerant halophilic bacterium-OKH with an ability to produce extracellular halophilic, alkali-tolerant, organic solvent stable, and moderately thermostable xylanase was isolated from salt salterns of Mithapur region, Gujarat, India. Identification of the bacterium was done based upon biochemical tests and 16S rRNA sequence. Maximum xylanase production was achieved at pH 9.0 and 37°C temperature in the medium containing 15% NaCl and 1% (w/v) corn cobs. Sugarcane bagasse and whe...

  19. Aminomonas paucivorans gen. nov., sp. nov., a mesophilic, anaerobic, amino-acid-utilizing bacterium

    OpenAIRE

    Baena, S.; Fardeau, Marie-Laure; Ollivier, Bernard; Labat, Marc; Thomas, P; Garcia, Jean-Louis; Patel, B.K.C.

    1999-01-01

    A novel, asaccharolytic, amino-acid-degrading bacterium, designated strain GLU-3T, was isolated from an anaerobic lagoon of a dairy wastewater treatment plant. Strain GLU-3T stained Gram-negative and was an obligately anaerobic, non-spore-forming, slightly curved, rod-shaped bacterium (0.3 x 4.0-6.0 micrometers) which existed singly or in pairs. The DNA G+C content was 43 mol%. Optimum growth occurred at 35°C and pH 7.5 on arginine, histidine, threonine and glycine. Acetate was the end-produc...

  20. Virgibacillus salarius sp. nov., a novel halophilic bacterium isolated from a Saharan salt lake

    OpenAIRE

    Hua, Ngoc-Phuc; Amel, Hamza-Chaffai; Vreeland, Russell H.; Isoda, Hiroko; Naganuma, Takeshi

    2008-01-01

    A Gram-positive, endospore-forming, rod-shaped and moderately halophilic bacterium was isolated from a salt crust sample collected in Gharsa salt lake (Chott el Gharsa), Tunisia. The newly isolated bacterium designated SA-Vb1T was identified based on polyphasic taxonomy including genotypic, phenotypic and chemotaxonomic characterization. Strain SA-Vb1T was closely related to Virgibacillus marismortui and V. olivae with 16S rRNA gene sequence similarities of 99.7% and 99.4%, respectively. Howe...

  1. Marinobacter hydrocarbonoclasticus NY-4, a novel denitrifying, moderately halophilic marine bacterium

    OpenAIRE

    Li, Rongpeng; Zi, Xiaoli; Wang, Xinfeng; Zhang, Xia; Gao, Haofeng; Hu, Nan

    2013-01-01

    The isolation and characterization of a novel halophilic denitrifying marine bacterium is described. The halophilic bacterium, designated as NY-4, was isolated from soil in Yancheng City, China, and identified as Marinobacter hydrocarbonoclasticus by 16S rRNA gene sequence phylogenetic analysis. This organism can grow in NaCl concentrations ranging from 20 to 120 g/L. Optimum growth occurs at 80 g/L NaCl and pH 8.0. The organism can grow on a broad range of carbon sources and demonstrated eff...

  2. Genome sequence of Symbiobacterium thermophilum, an uncultivable bacterium that depends on microbial commensalism

    OpenAIRE

    Ueda, Kenji; YAMASHITA Atsushi; Ishikawa, Jun; Shimada, Masafumi; Watsuji, Tomo-o; Morimura, Kohji; Ikeda, Haruo; Hattori, Masahira; Beppu, Teruhiko

    2004-01-01

    Symbiobacterium thermophilum is an uncultivable bacterium isolated from compost that depends on microbial commensalism. The 16S ribosomal DNA-based phylogeny suggests that this bacterium belongs to an unknown taxon in the Gram-positive bacterial cluster. Here, we describe the 3.57 Mb genome sequence of S.thermophilum. The genome consists of 3338 protein-coding sequences, out of which 2082 have functional assignments. Despite the high G + C content (68.7%), the genome is closest to that of Fir...

  3. Isolation from the Sorghum bicolor Mycorrhizosphere of a Bacterium Compatible with Arbuscular Mycorrhiza Development and Antagonistic towards Soilborne Fungal Pathogens

    Science.gov (United States)

    Budi, S. W.; van Tuinen, D.; Martinotti, G.; Gianinazzi, S.

    1999-01-01

    A gram-positive bacterium with antagonistic activity towards soilborne fungal pathogens has been isolated from the mycorrhizosphere of Sorghum bicolor inoculated with Glomus mosseae. It has been identified as Paenibacillus sp. strain B2 based on its analytical profile index and on 16S ribosomal DNA analysis. Besides having antagonistic activity, this bacterium stimulates mycorrhization. PMID:10543835

  4. Isolation from swine feces of a bacterium which decarboxylates p-hydroxyphenylacetic acid to 4-methylphenol (p-cresol).

    OpenAIRE

    L. A. Ward; Johnson, K A; Robinson, I.M.; Yokoyama, M T

    1987-01-01

    An obligate anaerobe has been isolated from swine feces which decarboxylates p-hydroxyphenylacetic acid to 4-methylphenol (p-cresol). The bacterium was an ovoid rod, gram positive, nonsporeforming, and nonmotile. Lactate and acetate were major end products of glucose fermentation. Based on its characteristics, the bacterium is tentatively assigned to the genus Lactobacillus.

  5. Comment on "A bacterium that degrades and assimilates poly(ethylene terephthalate)".

    Science.gov (United States)

    Yang, Yu; Yang, Jun; Jiang, Lei

    2016-08-19

    Yoshida et al (Report, 11 March 2016, p. 1196) reported that the bacterium Ideonella sakaiensis 201-F6 can degrade and assimilate poly(ethylene terephthalate) (PET). However, the authors exaggerated degradation efficiency using a low-crystallinity PET and presented no straightforward experiments to verify depolymerization and assimilation of PET. Thus, the authors' conclusions are rather misleading. PMID:27540159

  6. Transcriptome analysis of the rhizosphere bacterium Azospirillum brasilense reveals an extensive auxin response.

    Science.gov (United States)

    Van Puyvelde, Sandra; Cloots, Lore; Engelen, Kristof; Das, Frederik; Marchal, Kathleen; Vanderleyden, Jos; Spaepen, Stijn

    2011-05-01

    The rhizosphere bacterium Azospirillum brasilense produces the auxin indole-3-acetic acid (IAA) through the indole-3-pyruvate pathway. As we previously demonstrated that transcription of the indole-3-pyruvate decarboxylase (ipdC) gene is positively regulated by IAA, produced by A. brasilense itself or added exogenously, we performed a microarray analysis to study the overall effects of IAA on the transcriptome of A. brasilense. The transcriptomes of A. brasilense wild-type and the ipdC knockout mutant, both cultured in the absence and presence of exogenously added IAA, were compared.Interfering with the IAA biosynthesis/homeostasis in A. brasilense through inactivation of the ipdC gene or IAA addition results in much broader transcriptional changes than anticipated. Based on the multitude of changes observed by comparing the different transcriptomes, we can conclude that IAA is a signaling molecule in A. brasilense. It appears that the bacterium, when exposed to IAA, adapts itself to the plant rhizosphere, by changing its arsenal of transport proteins and cell surface proteins. A striking example of adaptation to IAA exposure, as happens in the rhizosphere, is the upregulation of a type VI secretion system (T6SS) in the presence of IAA. The T6SS is described as specifically involved in bacterium-eukaryotic host interactions. Additionally, many transcription factors show an altered regulation as well, indicating that the regulatory machinery of the bacterium is changing.

  7. Draft Genome Sequence of a Thermophilic Desulfurization Bacterium, Geobacillus thermoglucosidasius Strain W-2

    Science.gov (United States)

    Zhu, Lin; Li, Mingchang; Guo, Shuyi

    2016-01-01

    Geobacillus thermoglucosidasius strain W-2 is a thermophilic bacterium isolated from a deep-subsurface oil reservoir in northern China, which is capable of degrading organosulfur compounds. Here, we report the draft genome sequence of G. thermoglucosidasius strain W-2, which may help to elucidate the genetic basis of biodegradation of organosulfur pollutants under heated conditions. PMID:27491977

  8. Genome sequence of Citrobacter sp. strain A1, a dye-degrading bacterium.

    Science.gov (United States)

    Chan, Giek Far; Gan, Han Ming; Rashid, Noor Aini Abdul

    2012-10-01

    Citrobacter sp. strain A1, isolated from a sewage oxidation pond, is a facultative aerobe and mesophilic dye-degrading bacterium. This organism degrades azo dyes efficiently via azo reduction and desulfonation, followed by the successive biotransformation of dye intermediates under an aerobic environment. Here we report the draft genome sequence of Citrobacter sp. A1.

  9. Cloning, sequencing, and sequence analysis of two novel plasmids from the thermophilic anaerobic bacterium Anaerocellum thermophilum

    DEFF Research Database (Denmark)

    Clausen, Anders; Mikkelsen, Marie Just; Schrøder, I.;

    2004-01-01

    The nucleotide sequence of two novel plasmids isolated from the extreme thermophilic anaerobic bacterium Anaerocellum thermophilum DSM6725 (A. thermophilum), growing optimally at 70degreesC, has been determined. pBAS2 was found to be a 3653 bp plasmid with a GC content of 43%, and the sequence...

  10. The Mechanism and Usage for Enhanced Oil Recovery by Chemotaxis of Bacterium BS2

    Institute of Scientific and Technical Information of China (English)

    LiYiqian; JingGuicheng; GaoShusheng; XungWei

    2005-01-01

    Due to its chemotaxis, the motion ability of bacterium BS2 is very strong, and under the microscope, the distribution grads of bacterium concentration can be seen at the oil-water interface. During the experiments in glass box, it can be observed, with eyes, because of the chemotaxis, that muddy gets thicker and thicker at the interface gradually, and it is measured there, from sampling, that the bacterium concentration is 109 cells/mL, pH value 4.4 and the concentration of bio-surfactant 2.87%; The microbial oil-displacement experiments are carried out in emulational network models, and the oil-displacement mechanism by the bacterium and its metabolizing production is studied. And, during oil-displacement experiments in the gravel-input glass models, because of the profile control of thalli and the production, the sweep area of subsequent waterflood becomes wider, which can be seen with eyes and the recovery is enhanced by 13.6%. Finally, the successful field test is introduced in brief: the ratio of response producers is 85.7%, and the water-cut degrades by 6.4%, while 20038t oil has increased in accumulative total in 2 years.

  11. Cadmium and zinc interactions with a Gram-positive soil bacterium.

    NARCIS (Netherlands)

    Plette, A.C.C.

    1996-01-01

    A detailed study is presented on the cadmium and zinc sorption to both isolated cell walls and intact, living cells of the Gram-positive soil bacterium Rhodococcus erythropolis A177. Acid/base titrations were performed on isolated cell wall material to characterize the type and amount of reactive si

  12. Active efflux systems in the solvent-tolerant bacterium Pseudomonas putida S12

    NARCIS (Netherlands)

    Kieboom, J.

    2002-01-01

    The aim of the research presented in this thesis was to study the molecular mechanisms of organic solvent tolerance in Pseudomonas putida S12. This bacterium is capable of growth at saturated solvent concentrations, which are lethal to normal bacteria. Organic solve

  13. Complete genome sequence of Pandoraea thiooxydans DSM 25325(T), a thiosulfate-oxidizing bacterium.

    Science.gov (United States)

    Yong, Delicia; Ee, Robson; Lim, Yan-Lue; Yu, Choo-Yee; Ang, Geik-Yong; How, Kah-Yan; Tee, Kok-Keng; Yin, Wai-Fong; Chan, Kok-Gan

    2016-01-10

    Pandoraea thiooxydans DSM 25325(T) is a thiosulfate-oxidizing bacterium isolated from rhizosphere soils of a sesame plant. Here, we present the first complete genome of P. thiooxydans DSM 25325(T). Several genes involved in thiosulfate oxidation and biodegradation of aromatic compounds were identified.

  14. Thermaerobacter litoralis sp. nov., a strictly aerobic and thermophilic bacterium isolated from a coastal hydrothermal field

    DEFF Research Database (Denmark)

    Tanaka, Reiji; Kawaichi, Satoshi; Nishimura, Hiroshi;

    2006-01-01

    A novel thermophilic bacterium, strain KW1T, was isolated from a coastal hydrothermal field on the Satsuma Peninsula, Kagoshima Prefecture, Japan. The variably Gram-stained cells were motile rods with flagella, did not form spores and proliferated at 52-78°C (optimum, 70°C), pH 5-8 (optimum, pH 7...

  15. Draft Genome Sequence of Photorhabdus luminescens subsp. laumondii HP88, an Entomopathogenic Bacterium Isolated from Nematodes.

    Science.gov (United States)

    Ghazal, Shimaa; Oshone, Rediet; Simpson, Stephen; Morris, Krystalynne; Abebe-Akele, Feseha; Thomas, W Kelley; Khalil, Kamal M; Tisa, Louis S

    2016-01-01

    Photorhabdus luminescens subsp. laumondii HP88 is an entomopathogenic bacterium that forms a symbiotic association with Heterorhabditis nematodes. We report here a 5.27-Mbp draft genome sequence for P. luminescens subsp. laumondii HP88, with a G+C content of 42.4% and containing 4,243 candidate protein-coding genes. PMID:26988056

  16. Whole-Genome Shotgun Sequence of Pseudomonas viridiflava, a Bacterium Species Pathogenic to Arabidopsis thaliana

    OpenAIRE

    Lefort, Francois; Calmin, Gautier; Crovadore, Julien; Osteras, Magne; Farinelli, Laurent

    2013-01-01

    We report here the first whole-genome shotgun sequence of Pseudomonas viridiflava strain UASWS38, a bacterium species pathogenic to the biological model plant Arabidopsis thaliana but also usable as a biological control agent and thus of great scientific interest for understanding the genetics of plant-microbe interactions.

  17. Draft Genome Sequence of the Moderately Thermophilic Bacterium Schleiferia thermophila Strain Yellowstone (Bacteroidetes)

    OpenAIRE

    Thiel, Vera; Hamilton, Trinity L.; Tomsho, Lynn P.; Burhans, Richard; Gay, Scott E.; Ramaley, Robert F.; Stephan C Schuster; Steinke, Laurey; Bryant, Donald A.

    2014-01-01

    The draft genome sequence of the moderately thermophilic bacterium Schleiferia thermophila strain Yellowstone (Bacteroidetes), isolated from Octopus Spring (Yellowstone National Park, WY, USA) was sequenced and comprises 2,617,694 bp in 35 contigs. The draft genome is predicted to encode 2,457 protein coding genes and 37 tRNA encoding genes and two rRNA operons.

  18. First Insights into the Genome of the Moderately Thermophilic Bacterium Clostridium tepidiprofundi SG 508T.

    Science.gov (United States)

    Poehlein, Anja; Friedrich, Ines; Krüger, Larissa; Daniel, Rolf

    2016-01-01

    The moderately thermophilic bacterium Clostridium tepidiprofundi is Gram-positive and belongs to clostridial cluster I. It was isolated from a hydrothermal vent chimney. Substrates utilized by C. tepidiprofundi include casein, peptone, tryptone, yeast extract, beef extract, starch, maltose, and glucose. The genome consists of one replicon (3.06 Mb). PMID:27174286

  19. First Insights into the Genome of the Moderately Thermophilic Bacterium Clostridium tepidiprofundi SG 508T

    OpenAIRE

    Poehlein, Anja; Friedrich, Ines; Krüger, Larissa; Daniel, Rolf

    2016-01-01

    The moderately thermophilic bacterium Clostridium tepidiprofundi is Gram-positive and belongs to clostridial cluster I. It was isolated from a hydrothermal vent chimney. Substrates utilized by C. tepidiprofundi include casein, peptone, tryptone, yeast extract, beef extract, starch, maltose, and glucose. The genome consists of one replicon (3.06 Mb).

  20. Modeling of Cd Uptake and Efflux Kinetics in Metal-Resistant Bacterium Cupriavidus metallidurans

    NARCIS (Netherlands)

    Hajdu, R.; Pinheiro, J.P.; Galceran, J.; Slaveykova, V.I.

    2010-01-01

    The Model of Uptake with Instantaneous Adsorption and Efflux, MUIAE, describing and predicting the overall Cd uptake by the metal-resistant bacterium Cupriavidus metallidurans CH34, is presented. MUIAE takes into account different processes at the bacteria-medium interface with specific emphasis on

  1. Two-dimensional gel-based alkaline proteome of the probiotic bacterium Lactobacillus acidophilus NCFM

    DEFF Research Database (Denmark)

    Majumder, Avishek; Cai, Liyang; Ejby, Morten;

    2012-01-01

    Lactobacillus acidophilus NCFM (NCFM) is a well‐documented probiotic bacterium isolated from human gut. Detailed 2D gel‐based NCFM proteomics addressed the so‐called alkaline range, i.e., pH 6–11. Proteins were identified in 150 of the 202 spots picked from the Coomassie Brilliant Blue stained 2D...

  2. Draft Genome Sequence of Photorhabdus luminescens subsp. laumondii HP88, an Entomopathogenic Bacterium Isolated from Nematodes

    OpenAIRE

    Ghazal, Shimaa; Oshone, Rediet; Simpson, Stephen,; Morris, Krystalynne; Abebe-Akele, Feseha; Thomas, W. Kelley; Khalil, Kamal M.; Tisa, Louis S.

    2016-01-01

    Photorhabdus luminescens subsp. laumondii HP88 is an entomopathogenic bacterium that forms a symbiotic association with Heterorhabditis nematodes. We report here a 5.27-Mbp draft genome sequence for P. luminescens subsp. laumondii HP88, with a G+C content of 42.4% and containing 4,243 candidate protein-coding genes.

  3. Genome Sequence of Bacillus mycoides B38V, a Growth-Promoting Bacterium of Sunflower.

    Science.gov (United States)

    Ambrosini, Adriana; Sant'Anna, Fernando Hayashi; de Souza, Rocheli; Tadra-Sfeir, Michele; Faoro, Helisson; Alvarenga, Samuel M; Pedrosa, Fabio Oliveira; Souza, Emanuel Maltempi; Passaglia, Luciane M P

    2015-01-01

    Bacillus mycoides B38V is a bacterium isolated from the sunflower rhizosphere that is able to promote plant growth and N uptake. The genome of the isolate has approximately 5.80 Mb and presents sequence codifiers for plant growth-promoting characteristics, such as nitrate reduction and ammonification and iron-siderophore uptake. PMID:25838494

  4. Genome Sequence of Bacillus mycoides B38V, a Growth-Promoting Bacterium of Sunflower

    OpenAIRE

    Ambrosini, Adriana; Sant’Anna, Fernando Hayashi; de Souza, Rocheli; Tadra-Sfeir, Michele; Faoro, Helisson; Alvarenga, Samuel M.; Pedrosa, Fabio Oliveira; Souza, Emanuel Maltempi; Passaglia, Luciane M. P.

    2015-01-01

    Bacillus mycoides B38V is a bacterium isolated from the sunflower rhizosphere that is able to promote plant growth and N uptake. The genome of the isolate has approximately 5.80 Mb and presents sequence codifiers for plant growth-promoting characteristics, such as nitrate reduction and ammonification and iron-siderophore uptake.

  5. Biohydrogen Production by the Thermophilic Bacterium Caldicellulosiruptor saccharolyticus: Current Status and Perspectives

    NARCIS (Netherlands)

    Bielen, A.A.M.; Verhaart, M.R.A.; Oost, van der J.; Kengen, S.W.M.

    2013-01-01

    Caldicellulosiruptor saccharolyticus is one of the most thermophilic cellulolytic organisms known to date. This Gram-positive anaerobic bacterium ferments a broad spectrum of mono-, di- and polysaccharides to mainly acetate, CO2 and hydrogen. With hydrogen yields approaching the theoretical limit fo

  6. Isolation and algae-lysing characteristics of the algicidal bacterium B5

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Water blooms have become a worldwide environmental problem. Recently, algicidal bacteria have attracted wide attention as possible agents for inhibiting algal water blooms. In this study, one strain of algicidal bacterium B5 was isolated from activated sludge. On the basis of analysis of its physiological characteristics and 16S rDNA gene sequence, it was identified as Bacillus fusiformis. Its algae-lysing characteristics on Microcystis aeruginosa, Chlorella and Scenedesmus were tested. The results showed that: (1) the algicidal bacterium B5 is a Gram-negative bacterium. The 16S rDNA nucleotide sequence homology of strain B5 with 2 strains of B. fusiformis reached 99.86%, so B5 was identified as B. fusiformis; (2) the algal-lysing effects of the algicidal bacterium B5 on M. aeruginosa, Chlorella and Scenedesmus were pronounced. The initial bacterial and algal cell densities strongly influence the removal rates of chlorophyll-a. The greater the initial bacterial cell density, the faster the degradation of chlorophyll-a. The greater the initial algal cell density, the slower the degradation of chlorophyll-a. When the bacterial cell density was 3.6 × 107 cells/ml, nearly 90% of chlorophyll-a was removed. When the chlorophyll-a concentration was less than 550 μg/L, about 70 % was removed; (3) the strain B5 lysed algae not directly but by secreting metabolites and these metabolites could bear heat treatment.

  7. The construction of an engineered bacterium to remove cadmium from wastewater.

    Science.gov (United States)

    Chang, S; Shu, H

    2014-01-01

    The removal of cadmium (Cd) from wastewater before it is released from factories is important for protecting human health. Although some researchers have developed engineered bacteria, the resistance of these engineered bacteria to Cd have not been improved. In this study, two key genes involved in glutathione synthesis (gshA and gshB), a serine acetyltransferase gene (cysE), a Thlaspi caerulescens phytochelatin synthase gene (TcPCS1), and a heavy metal ATPase gene (TcHMA3) were transformed into Escherichia coli BL21. The resistance of the engineered bacterium to Cd was significantly greater than that of the initial bacterium and the Cd accumulation in the engineered bacterium was much higher than in the initial bacterium. In addition, the Cd resistance of the bacteria harboring gshB, gshA, cysE, and TcPCS1 was higher than that of the bacteria harboring gshA, cysE, and TcPCS1. This finding demonstrated that gshB played an important role in glutathione synthesis and that the reaction catalyzed by glutathione synthase was the limiting step for producing phytochelatins. Furthermore, TcPCS1 had a greater specificity and a higher capacity for removing Cd than SpPCS1, and TcHMA3 not only played a role in T. caerulescens but also functioned in E. coli.

  8. Complete Genome Sequence of Sphingomonas sp. Strain NIC1, an Efficient Nicotine-Degrading Bacterium

    Science.gov (United States)

    Zhu, Xiongyu; Wang, Weiwei; Xu, Ping

    2016-01-01

    Sphingomonas sp. strain NIC1, an efficient nicotine-degrading bacterium, was isolated from tobacco leaves. Here, we present the complete genome sequence of strain NIC1, which contains one circular chromosome and two circular plasmids. The genomic information will provide insights into its molecular mechanism for nicotine degradation. PMID:27417841

  9. Complete genome sequence of the bioleaching bacterium Leptospirillum sp. group II strain CF-1.

    Science.gov (United States)

    Ferrer, Alonso; Bunk, Boyke; Spröer, Cathrin; Biedendieck, Rebekka; Valdés, Natalia; Jahn, Martina; Jahn, Dieter; Orellana, Omar; Levicán, Gloria

    2016-03-20

    We describe the complete genome sequence of Leptospirillum sp. group II strain CF-1, an acidophilic bioleaching bacterium isolated from an acid mine drainage (AMD). This work provides data to gain insights about adaptive response of Leptospirillum spp. to the extreme conditions of bioleaching environments. PMID:26853478

  10. An ATP transport system in the intracellular bacterium, Bdellovibrio bacteriovorus 109J.

    OpenAIRE

    Ruby, E G; McCabe, J B

    1986-01-01

    The intracellularly growing bacterium Bdellovibrio bacteriovorus 109J transports intact ATP by a specific, energy-requiring process. ATP transport does not involve either an ADP-ATP or an AMP-ATP exchange mechanism but, instead, has characteristics of an active transport permease. Kinetically distinct systems for ATP transport are expressed by the two developmental stages of the bdellovibrio life cycle.

  11. Draft Genome Sequence of the Moderately Halophilic Bacterium Pseudoalteromonas ruthenica Strain CP76.

    Science.gov (United States)

    de la Haba, Rafael R; Sánchez-Porro, Cristina; León, María José; Papke, R Thane; Ventosa, Antonio

    2013-05-23

    Pseudoalteromonas ruthenica strain CP76, isolated from a saltern in Spain, is a moderately halophilic bacterium belonging to the Gammaproteobacteria. Here we report the draft genome sequence, which consists of a 4.0-Mb chromosome, of this strain, which is able to produce the extracellular enzyme haloprotease CPI.

  12. Aerobic degradation of highly chlorinated polychlorobiphenyls by a marine bacterium, Pseudomonas CH07

    Digital Repository Service at National Institute of Oceanography (India)

    De, J.; Ramaiah, N.; Sarkar, A.

    and the other coplanar tetrachloro congener CB-77 was degraded by more than 40% within 40 hours by this microorganism. Apparently absence of bphC in this bacterium led to proposition of different mechanism of PCBs degradation. KEY WORDS: Pseudomonas CH07...

  13. Engineering a predatory bacterium as a proficient killer agent for intracellular bio-products recovery

    DEFF Research Database (Denmark)

    Martinez, Virginia; Herencias, Cristina; Jurkevitch, Edouard;

    2016-01-01

    This work examines the potential of the predatory bacterium Bdellovibrio bacteriovorus HD100, an obligate predator of other Gram-negative bacteria, as an external cell-lytic agent for recovering valuable intracellular bio-products produced by prey cultures. The bio-product targets to be recovered...

  14. Genome sequence of the mycorrhizal helper bacterium Pseudomonas fluorescens BBc6R8

    Energy Technology Data Exchange (ETDEWEB)

    Deveau, Aurelie [French National Insitute for Agricultural Research (INRA); Grob, Harald [University of Bonn, Germany; Morin, Emmanuelle [INRA, Nancy, France; Karpinets, Tatiana V [ORNL; Utturkar, Sagar M [ORNL; Mehnaz, Samina [University of the Punjab, Pakistan; Kurz, Sven [University of Bonn, Germany; Martin, Francis [INRA, Nancy, France; Frey-Klett, Pascale [INRA, Nancy, France; Labbe, Jessy L [ORNL

    2014-01-01

    We report the draft genome sequence of the mycorrhiza helper bacterium Pseudomonas fluorescens strain BBc6R8 . Several traits which could be involved in the mycorrhiza helper ability of the bacterial strain such as multiple secretion systems, auxin metabolism and phosphate mobilization were evidenced in the genome.

  15. Mechanisms of Stress Resistance and Gene Regulation in the Radioresistant Bacterium Deinococcus radiodurans.

    Science.gov (United States)

    Agapov, A A; Kulbachinskiy, A V

    2015-10-01

    The bacterium Deinococcus radiodurans reveals extraordinary resistance to ionizing radiation, oxidative stress, desiccation, and other damaging conditions. In this review, we consider the main molecular mechanisms underlying such resistance, including the action of specific DNA repair and antioxidation systems, and transcription regulation during the anti-stress response.

  16. Toxicity of herbicides used in the sugarcane crop to diazotrophic bacterium Herbaspirillum seropedicae

    OpenAIRE

    Sergio de Oliveira Procópio; Marcelo Ferreira Fernandes; Daniele Araújo Teles; José Guedes Sena Filho; Alberto Cargnelutti Filho; Marcelo Araújo Resende; Leandro Vargas

    2014-01-01

    The objective of this work was to identify herbicides used in the sugarcane crop that affects neither the growth, the development, of nor the process of biological nitrogen fixation (BNF) by the diazotrophic bacterium Herbaspirillum seropedicae. Eighteen herbicides (paraquat, ametryne, tebuthiuron, amicarbazone, diuron, metribuzin, [hexazinone + diuron], [hexazinone + clomazone], clomazone, isoxaflutole, sulfentrazone, oxyfluorfen, imazapic, imazapyr, [trifloxysulfuron sodium + ametryne], gly...

  17. A commensal symbiotic interrelationship for the growth of Symbiobacterium toebii with its partner bacterium, Geobacillus toebii

    Directory of Open Access Journals (Sweden)

    Masui Ryoji

    2011-10-01

    Full Text Available Abstract Background Symbiobacterium toebii is a commensal symbiotic thermophile that absolutely requires its partner bacterium Geobacillus toebii for growth. Despite development of an independent cultivation method using cell-free extracts, the growth of Symbiobacterium remains unknown due to our poor understanding of the symbiotic relationship with its partner bacterium. Here, we investigated the interrelationship between these two bacteria for growth of S. toebii using different cell-free extracts of G. toebii. Results Symbiobacterium toebii growth-supporting factors were constitutively produced through almost all growth phases and under different oxygen tensions in G. toebii, indicating that the factor may be essential components for growth of G. toebii as well as S. toebii. The growing conditions of G. toebii under different oxygen tension dramatically affected to the initial growth of S. toebii and the retarded lag phase was completely shortened by reducing agent, L-cysteine indicating an evidence of commensal interaction of microaerobic and anaerobic bacterium S. toebii with a facultative aerobic bacterium G. toebii. In addition, the growth curve of S. toebii showed a dependency on the protein concentration of cell-free extracts of G. toebii, demonstrating that the G. toebii-derived factors have nutrient-like characters but not quorum-sensing characters. Conclusions Not only the consistent existence of the factor in G. toebii during all growth stages and under different oxygen tensions but also the concentration dependency of the factor for proliferation and optimal growth of S. toebii, suggests that an important biosynthetic machinery lacks in S. toebii during evolution. The commensal symbiotic bacterium, S. toebii uptakes certain ubiquitous and essential compound for its growth from environment or neighboring bacteria that shares the equivalent compounds. Moreover, G. toebii grown under aerobic condition shortened the lag phase of S

  18. Draft genome of an Aerophobetes bacterium reveals a facultative lifestyle in deep-sea anaerobic sediments

    Institute of Scientific and Technical Information of China (English)

    Yong Wang; Zhao-Ming Gao; Jiang-Tao Li; Salim Bougouffa; Ren Mao Tian; Vladimir B.Bajic; Pei-Yuan Qian

    2016-01-01

    Aerophobetes (or CD12) is a recently defined bacterial phylum,of which the metabolic processes and ecological importance remain unclear.In the present study,we obtained the draft genome of an Aerophobetes bacterium TCS1 from saline sediment near the Thuwal cold seep in the Red Sea using a genome binning method.Analysis of 16S rRNA genes of TCS1 and close relatives revealed wide distribution of Aerophobetes in deep-sea sediments.Phylogenetic relationships showed affinity between Aerophobetes TCS1 and some thermophilic bacterial phyla.The genome of TCS1 (at least 1.27 Mbp)contains a full set of genes encoding core metabolic pathways,including glycolysis and pyruvate fermentation to produce acetyl-CoA and acetate.The identification of cross-membrane sugar transporter genes further indicates its potential ability to consume carbohydrates preserved in the sediment under the microbial mat.Aerophobetes bacterium TCS1 therefore probably carried out saccharolytic and fermentative metabolism.The genes responsible for autotrophic synthesis of acetyl-CoA via the Wood-Ljungdahl pathway were also found in the genome.Phylogenetic study of the essential genes for the Wood-Ljungdahl pathway implied relative independence of Aerophobetes bacterium from the known acetogens and methanogens.Compared with genomes of acetogenic bacteria,Aerophobetes bacterium TCS 1 genome lacks the genes involved in nitrogen metabolism,sulfur metabolism,signal transduction and cell motility.The metabolic activities of TCS1 might depend on geochemical conditions such as supplies of CO2,hydrogen and sugars,and therefore the TCS1 might be a facultative bacterium in anaerobic saline sediments near cold seeps.

  19. Draft genome of an Aerophobetes bacterium reveals a facultative lifestyle in deep-sea anaerobic sediments

    KAUST Repository

    Wang, Yong

    2016-07-01

    Aerophobetes (or CD12) is a recently defined bacterial phylum, of which the metabolic processes and ecological importance remain unclear. In the present study, we obtained the draft genome of an Aerophobetes bacterium TCS1 from saline sediment near the Thuwal cold seep in the Red Sea using a genome binning method. Analysis of 16S rRNA genes of TCS1 and close relatives revealed wide distribution of Aerophobetes in deep-sea sediments. Phylogenetic relationships showed affinity between Aerophobetes TCS1 and some thermophilic bacterial phyla. The genome of TCS1 (at least 1.27 Mbp) contains a full set of genes encoding core metabolic pathways, including glycolysis and pyruvate fermentation to produce acetyl-CoA and acetate. The identification of cross-membrane sugar transporter genes further indicates its potential ability to consume carbohydrates preserved in the sediment under the microbial mat. Aerophobetes bacterium TCS1 therefore probably carried out saccharolytic and fermentative metabolism. The genes responsible for autotrophic synthesis of acetyl-CoA via the Wood–Ljungdahl pathway were also found in the genome. Phylogenetic study of the essential genes for the Wood–Ljungdahl pathway implied relative independence of Aerophobetes bacterium from the known acetogens and methanogens. Compared with genomes of acetogenic bacteria, Aerophobetes bacterium TCS1 genome lacks the genes involved in nitrogen metabolism, sulfur metabolism, signal transduction and cell motility. The metabolic activities of TCS1 might depend on geochemical conditions such as supplies of CO2, hydrogen and sugars, and therefore the TCS1 might be a facultative bacterium in anaerobic saline sediments near cold seeps. © 2016, Science China Press and Springer-Verlag Berlin Heidelberg.

  20. Production of Functionally Active and Immunogenic Non-Glycosylated Protective Antigen from Bacillus anthracis in Nicotiana benthamiana by Co-Expression with Peptide-N-Glycosidase F (PNGase F) of Flavobacterium meningosepticum.

    Science.gov (United States)

    Mamedov, Tarlan; Chichester, Jessica A; Jones, R Mark; Ghosh, Ananya; Coffin, Megan V; Herschbach, Kristina; Prokhnevsky, Alexey I; Streatfield, Stephen J; Yusibov, Vidadi

    2016-01-01

    Bacillus anthracis has long been considered a potential biological warfare agent, and therefore, there is a need for a safe, low-cost and highly efficient anthrax vaccine with demonstrated long-term stability for mass vaccination in case of an emergency. Many efforts have been made towards developing an anthrax vaccine based on recombinant protective antigen (rPA) of B. anthracis, a key component of the anthrax toxin, produced using different expression systems. Plants represent a promising recombinant protein production platform due to their relatively low cost, rapid scalability and favorable safety profile. Previous studies have shown that full-length rPA produced in Nicotiana benthamiana (pp-PA83) is immunogenic and can provide full protection against lethal spore challenge; however, further improvement in the potency and stability of the vaccine candidate is necessary. PA of B. anthracis is not a glycoprotein in its native host; however, this protein contains potential N-linked glycosylation sites, which can be aberrantly glycosylated during expression in eukaryotic systems including plants. This glycosylation could affect the availability of certain key epitopes either due to masking or misfolding of the protein. Therefore, a non-glycosylated form of pp-PA83 was engineered and produced in N. benthamiana using an in vivo deglycosylation approach based on co-expression of peptide-N-glycosidase F (PNGase F) from Flavobacterium meningosepticum. For comparison, versions of pp-PA83 containing point mutations in six potential N-glycosylation sites were also engineered and expressed in N. benthamiana. The in vivo deglycosylated pp-PA83 (pp-dPA83) was shown to have in vitro activity, in contrast to glycosylated pp-PA83, and to induce significantly higher levels of toxin-neutralizing antibody responses in mice compared with glycosylated pp-PA83, in vitro deglycosylated pp-PA83 or the mutated versions of pp-PA83. These results suggest that pp-dPA83 may offer advantages

  1. Evaluation of Biosynthetic Pathways of 2Н- and 13С-Labeled Amino Acids by an Obligate Methylotrophic Bacterium Methylobacillus Flagellatum and a Facultative Methylotrophic Bacterium Brevibacterium Methylicum

    Directory of Open Access Journals (Sweden)

    Oleg Mosin

    2016-06-01

    Full Text Available By the method of electron impact mass-spectrometry was studied the pathways of biosynthesis of 2H, 13C-labeled amino acids of a facultative methylotrophic bacterium Brevibacterium methylicum and an obligate methylotrophic bacterium Methylobacillus flagellatum obtained on growth media containing as a source of stable isotopes [2H]methanol, [13C]methanol and 2H2O. For mass-spectrometric analysis the multicomponential mixtures of 2H- and 13C-labeled amino acids, derived from cultural media and protein hydrolysates after hydrolysis in 6 M 2HСl (3 % phenol and 2 M Ва(OH2 were modified into N-benzyloxycarbonyl-derivatives of amino acids as well as into methyl esters of N-5-(dimethylaminonaphthalene-1-sulfonyl chloride (dansyl derivatives of [2H, 13С]amino acids, which were preparative separated using a method of reverse-phase HCLP. Biosynthetically obtained 2H- and 13C-labeled amino acids represented the mixtures differing in quantities of isotopes incorporated into molecule. The levels of 2H and 13С enrichment of secreted amino acids and amino acid resigues of protein were found to vary from 20,0 atom % to L-leucine/isoleucine up to 97,5 atom % for L-alanine depending on concentration of 2H- and 13C-labelled substrates.

  2. Influence of pH and Oxidant Ozone to Amount of Bacterium Coliform at Hospital Waste

    International Nuclear Information System (INIS)

    Influence of pH and oxidant ozone to amount of bacterium coliform at hospital waste have been done. As sample is liquid waste Public Hospital of town (RSUD) Yogyakarta. Sample waste processed by 3 kinds of treatment, that is first certain ozone waste during, that is waste given by the third and just chalk of waste given by the certain and ozonization chalk during. From third the treatment, in the reality third treatment which can give the maximal result, that is waste given the chalk until pH waste 8.5 and ozonization during 40 minute give the following result : bacterium coliform from 810.000 MPN become 0 MPN ( cell / 100 mL). This result have fulfilled the conditions as according to decision of Governor of DIY no. 65 year 1999 for the waste of faction II, that is waste used for the irrigation of fishery and agriculture. (author)

  3. Crystal structure of ribosomal protein L1 from the bacterium Aquifex aeolicus

    Science.gov (United States)

    Nikonova, E. Yu.; Tishchenko, S. V.; Gabdulkhakov, A. G.; Shklyaeva, A. A.; Garber, M. B.; Nikonov, S. V.; Nevskaya, N. A.

    2011-07-01

    The crystal structure of ribosomal protein L1 from the bacterium Aquifex aeolicus was solved by the molecular-replacement method and refined to R cryst = 19.4% and R free = 25.1% at 2.1 Å protein consists of two domains linked together by a flexible hinge region. In the structure under consideration, the domains are in close proximity and adopt a closed conformation. Earlier, this conformation has been found in the structure of protein L1 from the bacterium Thermus thermophilus, whereas the structures of archaeal L1 proteins and the structures of all L1 proteins in the RNA-bound form have an open conformation. The fact that a closed conformation was found in the structures of two L1 proteins which crystallize in different space groups and belong to different bacteria suggests that this conformation is a characteristic feature of L1 bacterial proteins in the free form.

  4. Effect of Sulfate Reduced Bacterium on Corrosion Behavior of 10CrMoAl Steel

    Institute of Scientific and Technical Information of China (English)

    WANG Hua; LIANG Cheng-hao

    2007-01-01

    The effects of sulfate reduced bacterium (SRB) on the corrosion behavior of 10CrMoAl steel in seawater were studied by chemical immersion, potentiodynamic polarization, electrochemical impedance spectroscopy measurement, and scanning electron microscope techniques. The results show that the content of element sulfur in the corrosion product of 10CrMoAl steel in seawater with SRB is up to 9.23%, which is higher than that of the same in sterile seawater. X-ray diffraction demonstrates that the main corrosion product is FeS. SRB increases the corrosion rate by anodic depolarization of the metabolized sulfide product. SEM observation indicates that the corrosion product is not distributed continuously; in addition, bacilliform sulfate-reduced bacterium accumulates on the local surface of 10CrMoAl steel. Hence, SRB enhances sensitivity to the localized corrosion of 10CrMoAl steel in seawater.

  5. Economic Game Theory to Model the Attenuation of Virulence of an Obligate Intracellular Bacterium.

    Science.gov (United States)

    Tago, Damian; Meyer, Damien F

    2016-01-01

    Diseases induced by obligate intracellular pathogens have a large burden on global human and animal health. Understanding the factors involved in the virulence and fitness of these pathogens contributes to the development of control strategies against these diseases. Based on biological observations, a theoretical model using game theory is proposed to explain how obligate intracellular bacteria interact with their host. The equilibrium in such a game shows that the virulence and fitness of the bacterium is host-triggered and by changing the host's defense system to which the bacterium is confronted, an evolutionary process leads to an attenuated strain. Although, the attenuation procedure has already been conducted in practice in order to develop an attenuated vaccine (e.g., with Ehrlichia ruminantium), there was a lack of understanding of the theoretical basis behind this process. Our work provides a model to better comprehend the existence of different phenotypes and some underlying evolutionary mechanisms for the virulence of obligate intracellular bacteria.

  6. Economic Game Theory to Model the Attenuation of Virulence of an Obligate Intracellular Bacterium

    Science.gov (United States)

    Tago, Damian; Meyer, Damien F.

    2016-01-01

    Diseases induced by obligate intracellular pathogens have a large burden on global human and animal health. Understanding the factors involved in the virulence and fitness of these pathogens contributes to the development of control strategies against these diseases. Based on biological observations, a theoretical model using game theory is proposed to explain how obligate intracellular bacteria interact with their host. The equilibrium in such a game shows that the virulence and fitness of the bacterium is host-triggered and by changing the host's defense system to which the bacterium is confronted, an evolutionary process leads to an attenuated strain. Although, the attenuation procedure has already been conducted in practice in order to develop an attenuated vaccine (e.g., with Ehrlichia ruminantium), there was a lack of understanding of the theoretical basis behind this process. Our work provides a model to better comprehend the existence of different phenotypes and some underlying evolutionary mechanisms for the virulence of obligate intracellular bacteria. PMID:27610355

  7. Isolation and biological characteristics of aerobic marine magnetotactic bacterium YSC-1

    Science.gov (United States)

    Gao, Jun; Pan, Hongmiao; Yue, Haidong; Song, Tao; Zhao, Yong; Chen, Guanjun; Wu, Longfei; Xiao, Tian

    2006-12-01

    Magnetotactic bacteria have become a hot spot of research in microbiology attracting intensive interest of researchers in multiple disciplinary fields. However, the studies were limited in few fastidious bacteria. The objective of this study aims at isolating new marine magnetic bacteria and better comprehension of magnetotactic bacteria. In this study, an aerobic magnetotactic bacterium YSC-1 was isolated from sediments in the Yellow Sea Cold Water Mass (YSCWM). In TEM, magnetic cells have one or several circular magnetosomes in diameter of 100nm, and consist of Fe and Co shown on energy dispersive X-ray spectrum. The biological and physiological characteristics of this bacterium were also described. The colour of YSC-1 colony is white in small rod. The gram stain is negative. Results showed that Strain YSC-1 differs from microaerophile magnetotactic bacteria MS-1 and WD-1 in biology.

  8. Isolation and biological characteristics of aerobic marine magnetotactic bacterium YSC-1

    Institute of Scientific and Technical Information of China (English)

    GAO Jun; PAN Hongmiao; YUE Haidong; SONG Tao; ZHAO Yong; CHEN Guanjun; Wu Longfei; XIAO Tian

    2006-01-01

    Magnetotactic bacteria have become a hot spot of research in microbiology attracting intensive interest of researchers in multiple disciplinary fields. However, the studies were limited in few fastidious bacteria. The objective of this study aims at isolating new marine magnetic bacteria and better comprehension of magnetotactic bacteria. In this study, an aerobic magnetotactic bacterium YSC-1 was isolated from sediments in the Yellow Sea Cold Water Mass (YSCWM). In TEM, magnetic cells have one or several circular magnetosomes in dimeter of 100nm, and consist of Fe and Co shown on energy dispersive X-ray spectrum. The biological and physiological characteristics of this bacterium were also described. The colour of YSC-1 colony is white in small rod. The gran stain is negative. Results showed that Strain YSC-1 differs from microaerophile magnetotactic bacteria MS-1 and WD-1 in biology.

  9. Microbiologically influenced corrosion of NiZn alloy coatings by Delftia acidovorans bacterium

    International Nuclear Information System (INIS)

    Highlights: ► Delftia acidovorans isolated from water treatment pipe system. ► Bacterium attached to the alloy coatings. ► Ecorr exhibited cathodic shift. ► Mass loss reached highest value after inoculation. ► Crevice corrosion was observed on the surface due to bacterium. - Abstract: In this study, Delftia acidovorans was isolated from water treatment pipe system and used to demonstrate microbiologically influenced corrosion of NiZn alloy coatings using electrochemical techniques. The surface morphologies and the corrosion products were determined using scanning electron microscopy (SEM) and energy dispersive X-ray spectra (EDS) analysis. Results showed that when the metabolic activity reached maximum level, corrosion activity of NiZn alloy coatings significantly increased in correlation with Ecorr, Icorr, QCM and Rct. Furthermore, crevice corrosion which has been seen due to bacterial adhesion confirms that D. acidovorans plays an important role in corrosion of NiZn alloy coating.

  10. Economic Game Theory to Model the Attenuation of Virulence of an Obligate Intracellular Bacterium.

    Science.gov (United States)

    Tago, Damian; Meyer, Damien F

    2016-01-01

    Diseases induced by obligate intracellular pathogens have a large burden on global human and animal health. Understanding the factors involved in the virulence and fitness of these pathogens contributes to the development of control strategies against these diseases. Based on biological observations, a theoretical model using game theory is proposed to explain how obligate intracellular bacteria interact with their host. The equilibrium in such a game shows that the virulence and fitness of the bacterium is host-triggered and by changing the host's defense system to which the bacterium is confronted, an evolutionary process leads to an attenuated strain. Although, the attenuation procedure has already been conducted in practice in order to develop an attenuated vaccine (e.g., with Ehrlichia ruminantium), there was a lack of understanding of the theoretical basis behind this process. Our work provides a model to better comprehend the existence of different phenotypes and some underlying evolutionary mechanisms for the virulence of obligate intracellular bacteria. PMID:27610355

  11. A Streamlined Strategy for Biohydrogen Production with Halanaerobium hydrogeniformans, an Alkaliphilic Bacterium.

    Science.gov (United States)

    Begemann, Matthew B; Mormile, Melanie R; Sitton, Oliver C; Wall, Judy D; Elias, Dwayne A

    2012-01-01

    Biofuels are anticipated to enable a shift from fossil fuels for renewable transportation and manufacturing fuels, with biohydrogen considered attractive since it could offer the largest reduction of global carbon budgets. Currently, lignocellulosic biohydrogen production remains inefficient with pretreatments that are heavily fossil fuel-dependent. However, bacteria using alkali-treated biomass could streamline biofuel production while reducing costs and fossil fuel needs. An alkaliphilic bacterium, Halanaerobiumhydrogeniformans, is described that is capable of biohydrogen production at levels rivaling neutrophilic strains, but at pH 11 and hypersaline conditions. H. hydrogeniformans ferments a variety of 5- and 6-carbon sugars derived from hemicellulose and cellulose including cellobiose, and forms the end products hydrogen, acetate, and formate. Further, it can also produce biohydrogen from switchgrass and straw pretreated at temperatures far lower than any previously reported and in solutions compatible with growth. Hence, this bacterium can potentially increase the efficiency and efficacy of biohydrogen production from renewable biomass resources.

  12. A Streamlined Strategy for Biohydrogen Production with Halanaerobium hydrogeniformans, an Alkaliphilic Bacterium

    Directory of Open Access Journals (Sweden)

    Matthew eBegemann

    2012-03-01

    Full Text Available Biofuels are anticipated to enable a shift from fossil fuels for renewable transportation and manufacturing fuels, with biohydrogen considered attractive since it could offer the largest reduction of global carbon budgets. Currently, lignocellulosic biohydrogen production remains inefficient with pretreatments that are heavily fossil fuel-dependent. However, bacteria using alkali-treated biomass could streamline biofuel production while reducing costs and fossil fuel needs. An alkaliphilic bacterium, Halanaerobium hydrogeniformans, is described that is capable of biohydrogen production at levels rivaling neutrophilic strains, but at pH 11 and hypersaline conditions. H. hydrogeniformans ferments a variety of 5- and 6- carbon sugars derived from hemicellulose and cellulose including cellobiose, and forms the end products hydrogen, acetate and formate. Further, it can also produce biohydrogen from switchgrass and straw pretreated at temperatures far lower than any previously reported and in solutions compatible with growth. Hence, this bacterium can potentially increase the efficiency and efficacy of biohydrogen production from renewable biomass resources.

  13. N-Acyl Dehydrotyrosines, Tyrosinase Inhibitors from the Marine Bacterium Thalassotalea sp. PP2-459.

    Science.gov (United States)

    Deering, Robert W; Chen, Jianwei; Sun, Jiadong; Ma, Hang; Dubert, Javier; Barja, Juan L; Seeram, Navindra P; Wang, Hong; Rowley, David C

    2016-02-26

    Thalassotalic acids A-C and thalassotalamides A and B are new N-acyl dehydrotyrosine derivatives produced by Thalassotalea sp. PP2-459, a Gram-negative bacterium isolated from a marine bivalve aquaculture facility. The structures were elucidated via a combination of spectroscopic analyses emphasizing two-dimensional NMR and high-resolution mass spectrometric data. Thalassotalic acid A (1) displays in vitro inhibition of the enzyme tyrosinase with an IC50 value (130 μM) that compares favorably to the commercially used control compounds kojic acid (46 μM) and arbutin (100 μM). These are the first natural products reported from a bacterium belonging to the genus Thalassotalea. PMID:26824128

  14. Regulation of dissimilatory sulfur oxidation in the purple sulfur bacterium Allochromatium vinosum

    OpenAIRE

    Frauke eGrimm; Bettina eFranz; Christiane eDahl

    2011-01-01

    In the purple sulfur bacterium Allochromatium vinosum, thiosulfate oxidation is strictly dependent on the presence of three periplasmic Sox proteins encoded by the soxBXAK and soxYZ genes. It is also well documented that proteins encoded in the dissimilatory sulfite reductase (dsr) operon, dsrABEFHCMKLJOPNRS, are essential for the oxidation of sulfur that is stored intracellularly as an obligatory intermediate during the oxidation of thiosulfate and sulfide. Until recently, detailed knowledge...

  15. The atherogenic bacterium Porphyromonas gingivalis evades circulating phagocytes by adhering to erythrocytes

    DEFF Research Database (Denmark)

    Belstrøm, Daniel; Holmstrup, Palle; Damgaard, Christian;

    2011-01-01

    A relationship between periodontitis and coronary heart disease has been investigated intensively. A pathogenic role for the oral bacterium Porphyromonas gingivalis has been suggested for both diseases. We examined whether complement activation by P. gingivalis strain ATCC 33277 allows the bacter....... gingivalis exploits RBCs as a transport vehicle, rendering it inaccessible to attack by phagocytes, and by doing so plays a role in the development of systemic diseases....

  16. Chlorhexidine resistance in a Gram-negative bacterium isolated from an aquatic source

    OpenAIRE

    Sekavec, Jeffrey G.; Moore, William T.; Gillock, Eric T.

    2013-01-01

    Aeromonas hydrophila is a Gram-negative bacterium of considerable importance in both clinical, especially nosocomial infections, and zoonotic respects, both aquatic and terrestrial infections. In addition to the ability to thrive in a wide range of conditions, A. hydrophila is resistant to numerous antibiotics and antimicrobials. In conjunction with Kansas State University and the Kansas Water Office, water samples from various locations within Kansas were screened for organisms resistant to ...

  17. A Highly Stable d-Amino Acid Oxidase of the Thermophilic Bacterium Rubrobacter xylanophilus

    OpenAIRE

    Takahashi, Shouji; Furukawara, Makoto; Omae, Keishi; Tadokoro, Namiho; Saito, Yayoi; Abe, Katsumasa; Kera, Yoshio

    2014-01-01

    d-Amino acid oxidase (DAO) is a biotechnologically attractive enzyme that can be used in a variety of applications, but its utility is limited by its relatively poor stability. A search of a bacterial genome database revealed a gene encoding a protein homologous to DAO in the thermophilic bacterium Rubrobacter xylanophilus (RxDAO). The recombinant protein expressed in Escherichia coli was a monomeric protein containing noncovalently bound flavin adenine dinucleotide as a cofactor. This protei...

  18. Calcium-ion mediated assembly and function of glycosylated flagellar sheath of marine magnetotactic bacterium

    OpenAIRE

    Lefèvre, Christopher T; Santini, Claire-Lise; Bernadac, Alain; Zhang, Wei-Jia; Ying LI; Wu, Long-Fei

    2010-01-01

    Abstract Flagella of some pathogens or marine microbes are sheathed by an apparent extension of the outer cell membrane. Although flagellar sheath has been reported for almost 60 years, little is known about its function and the mechanism of its assembly. Recently, we have observed a novel type of sheath that encloses a flagellar bundle, instead of a single flagellum, in a marine magnetotactic bacterium MO-1. Here, we reported isolation and characterization of the sheath which can ...

  19. Sensitivity of ribosomes of the hyperthermophilic bacterium Aquifex pyrophilus to aminoglycoside antibiotics.

    OpenAIRE

    Bocchetta, M; Huber, R.; Cammarano, P

    1996-01-01

    A poly(U)-programmed cell-free system from the hyperthermophilic bacterium Aquifex pyrophilus has been developed, and the susceptibility of Aquifex ribosomes to the miscoding-inducing and inhibitory actions of all known classes of aminoglycoside antibiotics has been assayed at temperatures (75 to 80 degrees C) close to the physiological optimum for cell growth. Unlike Thermotoga maritima ribosomes, which are systematically refractory to all known classes of aminoglycoside compounds (P. Londei...

  20. Campylobacter pylori, the spiral bacterium associated with human gastritis, is not a true Campylobacter sp.

    OpenAIRE

    Romaniuk, P J; Zoltowska, B; Trust, T J; Lane, D J; Olsen, G.J.; Pace, N R; Stahl, D A

    1987-01-01

    Comparison of partial 16S rRNA sequences from representative Campylobacter species indicates that the Campylobacter species form a previously undescribed basic eubacterial group, which is related to the other major groups only by very deep branching. This analysis was extended to include the spiral bacterium associated with human gastritis, Campylobacter pylori (formerly Campylobacter pyloridis). The distance between C. pylori and the other Campylobacter species is sufficient to exclude the p...

  1. Cadmium resistance and uptake by bacterium, Salmonella enterica 43C, isolated from industrial effluent.

    Science.gov (United States)

    Khan, Zaman; Rehman, Abdul; Hussain, Syed Z; Nisar, Muhammad A; Zulfiqar, Soumble; Shakoori, Abdul R

    2016-12-01

    Cadmium resistant bacterium, isolated from industrial wastewater, was characterized as Salmonella enterica 43C on the basis of biochemical and 16S rRNA ribotyping. It is first ever reported S. enterica 43C bared extreme resistance against heavy metal consortia in order of Pb(2+)>Cd(2+)>As(3+)>Zn(2+)>Cr(6+)>Cu(2+)>Hg(2+). Cd(2+) stress altered growth pattern of the bacterium in time dependent manner. It could remove nearly 57 % Cd(2+) from the medium over a period of 8 days. Kinetic and thermodynamic studies based on various adsorption isotherm models (Langmuir and Freundlich) depicted the Cd(2+) biosorption as spontaneous, feasible and endothermic in nature. Interestingly, the bacterium followed pseudo first order kinetics, making it a good biosorbent for heavy metal ions. The S. enterica 43C Cd(2+) processivity was significantly influenced by temperature, pH, initial Cd(2+) concentration, biomass dosage and co-metal ions. FTIR analysis of the bacterium revealed the active participation of amide and carbonyl moieties in Cd(2+) adsorption confirmed by EDX analysis. Electron micrographs beckoned further surface adsorption and increased bacterial size due to intracellular Cd(2+) accumulation. An overwhelming increase in glutathione and other non-protein thiols levels played a significant role in thriving oxidative stress generated by metal cations. Presence of metallothionein clearly depicted the role of such proteins in bacterial metal resistance mechanism. The present study results clearly declare S. enterica 43C a suitable candidate for green chemistry to bioremediate environmental Cd(2+).

  2. Draft Genome Sequence of the Antitrypanosomally Active Sponge-Associated Bacterium Actinokineospora sp. Strain EG49

    KAUST Repository

    Harjes, Janno

    2014-03-06

    The marine sponge-associated bacterium Actinokineospora sp. strain EG49 produces the antitrypanosomal angucycline-like compound actinosporin A. The draft genome of Actinokineospora sp. EG49 has a size of 7.5 megabases and a GC content of 72.8% and contains 6,629 protein-coding sequences (CDS). antiSMASH predicted 996 genes residing in 36 secondary metabolite gene clusters.

  3. Draft Genome Sequence of Uncultured SAR324 Bacterium lautmerah10, Binned from a Red Sea Metagenome

    KAUST Repository

    Haroon, Mohamed F.

    2016-02-11

    A draft genome of SAR324 bacterium lautmerah10 was assembled from a metagenome of a surface water sample from the Red Sea, Saudi Arabia. The genome is more complete and has a higher G+C content than that of previously sequenced SAR324 representatives. Its genomic information shows a versatile metabolism that confers an advantage to SAR324, which is reflected in its distribution throughout different depths of the marine water column.

  4. Five new amicoumacins isolated from a marine-derived Bacterium bacillus subtilis

    KAUST Repository

    Li, Yongxin

    2012-02-03

    Four novel amicoumacins, namely lipoamicoumacins A-D (1-4), and one new bacilosarcin analog (5) were isolated from culture broth of a marine-derived bacterium Bacillus subtilis, together with six known amicoumacins. Their structures were elucidated on the basis of extensive spectroscopic (2D NNR, IR, CD and MS) analysis and in comparison with data in literature. 2012 by the authors; licensee MDPI.

  5. Physiological Adaptation of the Bacterium Lactococcus lactis in Response to the Production of Human CFTR*

    OpenAIRE

    A. Steen; Wiederhold, E.; T Gandhi; Breitling, R.; D. J. Slotboom

    2010-01-01

    Biochemical and biophysical characterization of CFTR (the cystic fibrosis transmembrane conductance regulator) is thwarted by difficulties to obtain sufficient quantities of correctly folded and functional protein. Here we have produced human CFTR in the prokaryotic expression host Lactococcus lactis. The full-length protein was detected in the membrane of the bacterium, but the yields were too low (< 0.1% of membrane proteins) for in vitro functional and structural characterization, and indu...

  6. Complete genome sequence of Rufibacter tibetensis strain 1351, a radiation-resistant bacterium from Tibet plateau.

    Science.gov (United States)

    Zhang, Yi; Yu, Can; Zhou, Mengzhou; Tang, Jingfeng; Li, Xin; Wang, Zhi; Li, Zhijun; Yao, Juan; Li, Pei; Zheng, Guobin; Chen, Xiong; Dai, Jun

    2015-12-20

    Rufibacter tibetensis strain 1351, isolated from the soil of the Tibet plateau of China, belongs to the family of Cytophagaceae. It is a red-pigmented, gram-negative, strictly aerobic and rod-shaped bacterium and shows resistance to UV radiation. Here, we report its complete genome sequence, which can help us find the key genes of the carotenoid biosynthesis and resistance to UV radiation.

  7. Metabolism of 4-chloro-2-nitrophenol in a Gram-positive bacterium, Exiguobacterium sp. PMA

    OpenAIRE

    Arora Pankaj; Sharma Ashutosh; Mehta Richa; Shenoy Belle; Srivastava Alok; Singh Vijay

    2012-01-01

    Abstract Background Chloronitrophenols (CNPs) are widely used in the synthesis of dyes, drugs and pesticides, and constitute a major group of environmental pollutants. 4-Chloro-2-nitrophenol (4C2NP) is an isomer of CNPs that has been detected in various industrial effluents. A number of physicochemical methods have been used for treatment of wastewater containing 4C2NP. These methods are not as effective as microbial degradation, however. Results A 4C2NP-degrading bacterium, Exiguobacterium s...

  8. Sexual transmission of a plant pathogenic bacterium, Candidatus Liberibacter asiaticus, between conspecific insect vectors during mating.

    Directory of Open Access Journals (Sweden)

    Rajinder S Mann

    Full Text Available Candidatus Liberibacter asiaticus is a fastidious, phloem-inhabiting, gram-negative bacterium transmitted by Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae. The bacterium is the presumed causal agent of huanglongbing (HLB, one of the most destructive and economically important diseases of citrus. We investigated whether Las is transmitted between infected and uninfected D. citri adults during courtship. Our results indicate that Las was sexually transmitted from Las-infected male D. citri to uninfected females at a low rate (<4% during mating. Sexual transmission was not observed following mating of infected females and uninfected males or among adult pairs of the same sex. Las was detected in genitalia of both sexes and also in eggs of infected females. A latent period of 7 days or more was required to detect the bacterium in recipient females. Rod shaped as well as spherical structures resembling Las were observed in ovaries of Las-infected females with transmission electron microscopy, but were absent in ovaries from uninfected D. citri females. The size of the rod shaped structures varied from 0.39 to 0.67 µm in length and 0.19 to 0.39 µm in width. The spherical structures measured from 0.61 to 0.80 µm in diameter. This investigation provides convincing evidence that a plant pathogenic bacterium is sexually transmitted from male to female insects during courtship and established evidence that bacteria persist in reproductive organs. Moreover, these findings provide an alternative sexually horizontal mechanism for the spread of Las within populations of D. citri, even in the absence of infected host trees.

  9. Two New Cholic Acid Derivatives from the Marine Ascidian-Associated Bacterium Hasllibacter halocynthiae

    Directory of Open Access Journals (Sweden)

    Sung Hun Kim

    2012-10-01

    Full Text Available The investigation of secondary metabolites in liquid cultures of a recently discovered marine bacterium, Hasllibacter halocynthiae strain KME 002T, led to the isolation of two new cholic acid derivatives. The structures of these compounds were determined to be 3,3,12-trihydroxy-7-ketocholanic acid (1 and 3,3,12-trihydroxy-7-deoxycholanic acid (2 through HRFABMS and NMR data analyses.

  10. Biohydrogen Production by the Thermophilic Bacterium Caldicellulosiruptor saccharolyticus: Current Status and Perspectives

    OpenAIRE

    Kengen, Servé W. M.; Verhaart, Marcel R. A.; John van der Oost; Abraham A. M. Bielen

    2013-01-01

    Caldicellulosiruptor saccharolyticus is one of the most thermophilic cellulolytic organisms known to date. This Gram-positive anaerobic bacterium ferments a broad spectrum of mono-, di- and polysaccharides to mainly acetate, CO2 and hydrogen. With hydrogen yields approaching the theoretical limit for dark fermentation of 4 mol hydrogen per mol hexose, this organism has proven itself to be an excellent candidate for biological hydrogen production. This review provides an overview of the resear...

  11. Degradation of p-nitrophenol by the phototrophic bacterium Rhodobacter capsulatus.

    Science.gov (United States)

    Roldán, M D; Blasco, R; Caballero, F J; Castillo, F

    1998-01-01

    The phototrophic bacterium Rhodobacter capsulatus detoxified p-nitrophenol and 4-nitrocatechol. The bacterium tolerated moderate concentrations of p-nitrophenol (up to 0.5 mM) and degraded it under light at an optimal O2 pressure of 20 kPa. The bacterium did not metabolize the xenobiotic in the dark or under strictly anoxic conditions or high O2 pressure. Bacterial growth with acetate in the presence of p-nitrophenol took place with the simultaneous release of nonstoichiometric amounts of 4-nitrocatechol, which can also be degraded by the bacterium. Crude extracts from R. capsulatus produced 4-nitrocatechol from p-nitrophenol upon the addition of NAD(P)H, although at a very low rate. A constitutive catechol 1, 2-dioxygenase activity yielding cis,cis-muconate was also detected in crude extracts of R. capsulatus. Further degradation of 4-nitrocatechol included both nitrite- and CO2-releasing steps since: (1) a strain of R. capsulatus (B10) unable to assimilate nitrate and nitrite released nitrite into the medium when grown with p-nitrophenol or 4-nitrocatechol, and the nitrite concentration was stoichiometric with the 4-nitrocatechol degraded, and (2) cultures of R. capsulatus growing microaerobically produced low amounts of 14CO2 from radiolabeled p-nitrophenol. The radioactivity was also incorporated into cellular compounds from cells grown with uniformly labeled 14C-p-nitrophenol. From these results we concluded that the xenobiotic is used as a carbon source by R. capsulatus, but that only the strain able to assimilate nitrite (E1F1) can use p-nitrophenol as a nitrogen source.

  12. Purification and Characterization of a Feruloyl Esterase from the Intestinal Bacterium Lactobacillus acidophilus

    OpenAIRE

    Wang, Xiaokun; Geng, Xin; Egashira, Yukari; Sanada, Hiroo

    2004-01-01

    Dietary ferulic acid (FA), a significant antioxidant substance, is currently the subject of extensive research. FA in cereals exists mainly as feruloylated sugar ester. To release FA from food matrices, it is necessary to cleave ester cross-linking by feruloyl esterase (FAE) (hydroxycinnamoyl esterase; EC 3.1.1.73). In the present study, the FAE from a human typical intestinal bacterium, Lactobacillus acidophilus, was isolated, purified, and characterized for the first time. The enzyme was pu...

  13. Isolation and characterization of an anaerobic ruminal bacterium capable of degrading hydrolyzable tannins.

    OpenAIRE

    Nelson, K E; A. N. Pell; Schofield, P; Zinder, S

    1995-01-01

    An anaerobic diplococcoid bacterium able to degrade hydrolyzable tannins was isolated from the ruminal fluid of a goat fed desmodium (Desmodium ovalifolium), a tropical legume which contains levels as high as 17% condensed tannins. This strain grew under anaerobic conditions in the presence of up to 30 g of tannic acid per liter and tolerated a range of phenolic monomers, including gallic, ferulic, and p-coumaric acids. The predominant fermentation product from tannic acid breakdown was pyrog...

  14. Photobacterium damselae subsp. damselae, a bacterium pathogenic for marine animals and humans

    OpenAIRE

    Amable J. Rivas; Lemos, Manuel L.; Osorio, Carlos R.

    2013-01-01

    Photobacterium damselae subsp. damselae (formerly Vibrio damsela) is a pathogen of a variety of marine animals including fish, crustaceans, molluscs, and cetaceans. In humans, it can cause opportunistic infections that may evolve into necrotizing fasciitis with fatal outcome. Although the genetic basis of virulence in this bacterium is not completely elucidated, recent findings demonstrate that the phospholipase-D Dly (damselysin) and the pore-forming toxins HlyApl and HlyAch play a main role...

  15. Physiological features of Halomonas lionensis sp. nov., a novel bacterium isolated from a Mediterranean Sea sediment

    OpenAIRE

    Gaboyer, Frederic; Vandenabeele-Trambouze, Odile; Cao, Junwei; Ciobanu, Maria-Cristina; Jebbar, Mohamed; Le Romancer, Marc; Alain, Karine

    2014-01-01

    A novel halophilic bacterium, strain RHS90T, was isolated from marine sediments from the Gulf of Lions, in the Mediterranean Sea. Its metabolic and physiological characteristics were examined under various cultural conditions, including exposure to stressful ones (oligotrophy, high pressure and high concentrations of metals). Based on phylogenetic analysis of the 16S rRNA gene, the strain was found to belong to the genus Halomonas in the class Gammaproteobacteria. Its closest relatives are H....

  16. The Potential Biotechnological Applications of the Exopolysaccharide Produced by the Halophilic Bacterium Halomonas almeriensis

    OpenAIRE

    Victoria Béjar; Emilia Quesada; Juan Antonio Mata; Inmaculada Llamas; Hakima Amjres

    2012-01-01

    We have studied the extracellular polysaccharide (EPS) produced by the type strain, M8T, of the halophilic bacterium Halomonas almeriensis, to ascertain whether it might have any biotechnological applications. All the cultural parameters tested influenced both bacterial growth and polysaccharide production. EPS production was mainly growth-associated and under optimum environmental and nutritional conditions M8T excreted about...

  17. Genome Sequence of Marine Bacterium Idiomarina sp. Strain 28-8, Isolated from Korean Ark Shells.

    Science.gov (United States)

    Kim, Woo-Jin; Kim, Young-Ok; Kim, Dong-Gyun; Nam, Bo-Hye; Kong, Hee Jeong; Jung, Hyungtaek; Lee, Sang-Jun; Kim, Dong-Wook; Kim, Dae-Soo; Chae, Sung-Hwa

    2013-10-03

    Idiomarina sp. strain 28-8 is an aerobic, Gram-negative, flagellar bacterium isolated from the bodies of ark shells (Scapharca broughtonii) collected from underwater sediments in Gangjin Bay, South Korea. Here, we present the draft genome sequence of Idiomarina sp. 28-8 (2,971,606 bp, with a G+C content of 46.9%), containing 2,795 putative coding sequences.

  18. Insights in Nanoparticle-Bacterium Interactions: New Frontiers to Bypass Bacterial Resistance to Antibiotics.

    Science.gov (United States)

    Diab, Roudayna; Khameneh, Bahman; Joubert, Olivier; Duval, Raphael

    2015-01-01

    Nanotechnology has been revealed as a fundamental approach for antibiotics delivery. In this paper, recent findings demonstrating the superiority of nanocarried-antibiotics over "naked" ones and the ways by which nanoparticles can help to overwhelm bacterial drug resistance are reviewed. The second part of this paper sheds light on nanoparticle-bacterium interaction patterns. Finally, key factors affecting the effectiveness of nanoparticles interactions with bacteria are discussed.

  19. Cadmium resistance and uptake by bacterium, Salmonella enterica 43C, isolated from industrial effluent.

    Science.gov (United States)

    Khan, Zaman; Rehman, Abdul; Hussain, Syed Z; Nisar, Muhammad A; Zulfiqar, Soumble; Shakoori, Abdul R

    2016-12-01

    Cadmium resistant bacterium, isolated from industrial wastewater, was characterized as Salmonella enterica 43C on the basis of biochemical and 16S rRNA ribotyping. It is first ever reported S. enterica 43C bared extreme resistance against heavy metal consortia in order of Pb(2+)>Cd(2+)>As(3+)>Zn(2+)>Cr(6+)>Cu(2+)>Hg(2+). Cd(2+) stress altered growth pattern of the bacterium in time dependent manner. It could remove nearly 57 % Cd(2+) from the medium over a period of 8 days. Kinetic and thermodynamic studies based on various adsorption isotherm models (Langmuir and Freundlich) depicted the Cd(2+) biosorption as spontaneous, feasible and endothermic in nature. Interestingly, the bacterium followed pseudo first order kinetics, making it a good biosorbent for heavy metal ions. The S. enterica 43C Cd(2+) processivity was significantly influenced by temperature, pH, initial Cd(2+) concentration, biomass dosage and co-metal ions. FTIR analysis of the bacterium revealed the active participation of amide and carbonyl moieties in Cd(2+) adsorption confirmed by EDX analysis. Electron micrographs beckoned further surface adsorption and increased bacterial size due to intracellular Cd(2+) accumulation. An overwhelming increase in glutathione and other non-protein thiols levels played a significant role in thriving oxidative stress generated by metal cations. Presence of metallothionein clearly depicted the role of such proteins in bacterial metal resistance mechanism. The present study results clearly declare S. enterica 43C a suitable candidate for green chemistry to bioremediate environmental Cd(2+). PMID:27491862

  20. Bioinformatic Prediction of Gene Functions Regulated by Quorum Sensing in the Bioleaching Bacterium Acidithiobacillus ferrooxidans

    OpenAIRE

    Alvaro Banderas; Nicolas Guiliani

    2013-01-01

    The biomining bacterium Acidithiobacillus ferrooxidans oxidizes sulfide ores and promotes metal solubilization. The efficiency of this process depends on the attachment of cells to surfaces, a process regulated by quorum sensing (QS) cell-to-cell signalling in many Gram-negative bacteria. At. ferrooxidans has a functional QS system and the presence of AHLs enhances its attachment to pyrite. However, direct targets of the QS transcription factor AfeR remain unknown. In this study, a bioinforma...

  1. Comprehensive insights into the response of Alexandrium tamarense to algicidal component secreted by a marine bacterium

    OpenAIRE

    Lei, Xueqian; Li, Dong; Li, Yi; Chen, Zhangran; Chen, Yao; Cai, Guanjing; Yang, Xujun; Zheng, Wei; Zheng, Tianling

    2015-01-01

    Harmful algal blooms occur throughout the world, threatening human health, and destroying marine ecosystems. Alexandrium tamarense is a globally distributed and notoriously toxic dinoflagellate that is responsible for most paralytic shellfish poisoning incidents. The culture supernatant of the marine algicidal bacterium BS02 showed potent algicidal effects on A. tamarense ATGD98-006. In this study, we investigated the effects of this supernatant on A. tamarense at physiological and biochemica...

  2. Dynamic detection of a single bacterium: nonlinear rotation rate shifts of driven magnetic microsphere stages

    OpenAIRE

    McNaughton, Brandon H.; Agayan, Rodney R.; Kopelman, Raoul

    2006-01-01

    We report on a new technique which was used to detect single Escherichia coli that is based on the changes in the nonlinear rotation of a magnetic microsphere driven by an external magnetic field. The presence of one Escherichia Coli bacterium on the surface of a 2.0 micron magnetic microsphere caused an easily measurable change in the drag of the system and, therefore, in the nonlinear rotation rate. The straight-forward measurement uses standard microscopy techniques and the observed averag...

  3. Fourier transform infrared spectroscopic study of intact cells of the nitrogen-fixing bacterium Azospirillum brasilense

    Science.gov (United States)

    Kamnev, A. A.; Ristić, M.; Antonyuk, L. P.; Chernyshev, A. V.; Ignatov, V. V.

    1997-06-01

    The data of Fourier transform infrared (FTIR) spectroscopic measurements performed on intact cells of the soil nitrogen-fixing bacterium Azospirillum brasilense grown in a standard medium and under the conditions of an increased metal uptake are compared and discussed. The structural FTIR information obtained is considered together with atomic absorption spectrometry (AAS) data on the content of metal cations in the bacterial cells. Some methodological aspects concerning preparation of bacterial cell samples for FTIR measurements are also discussed.

  4. Genome Sequence of the Endophytic Bacterium Bacillus thuringiensis Strain KB1, a Potential Biocontrol Agent against Phytopathogens

    OpenAIRE

    Jeong, Haeyoung; Jo, Sung Hee; Hong, Chi Eun; Park, Jeong Mee

    2016-01-01

    Bacillus thuringiensis is the most widely known microbial pesticide used in agricultural applications. Herein, we report a draft genome sequence of the endophytic bacterium Bacillus thuringiensis strain KB1, which exhibits antagonism against phytopathogens.

  5. Genome Sequence of the Endophytic Bacterium Bacillus thuringiensis Strain KB1, a Potential Biocontrol Agent against Phytopathogens.

    Science.gov (United States)

    Jeong, Haeyoung; Jo, Sung Hee; Hong, Chi Eun; Park, Jeong Mee

    2016-04-21

    ITALIC! Bacillus thuringiensisis the most widely known microbial pesticide used in agricultural applications. Herein, we report a draft genome sequence of the endophytic bacterium ITALIC! Bacillus thuringiensisstrain KB1, which exhibits antagonism against phytopathogens.

  6. Draft Genome Sequence of Paenibacillus polymyxa EBL06, a Plant Growth-Promoting Bacterium Isolated from Wheat Phyllosphere

    OpenAIRE

    Liang, Shengxian; Jin, Decai; Wang, Xinxin; Fan, Haiyan; Bai, Zhihui

    2015-01-01

    Paenibacillus polymyxa strain EBL06 is a plant growth-promoting bacterium with high antifungal activity. The estimated genome of this strain is 5.68 Mb in size and harbors 4,792 coding sequences (CDSs).

  7. Genetic Engineering of a Radiation-Resistant Bacterium for Biodegradation of Mixed Wastes--Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Mary E. Lidstrom

    2003-12-26

    Aqueous mixed low level wastes (MLLW) containing radionuclides, solvents, and/or heavy metals represent a serious current and future problem for DOE environmental management and cleanup. In order to provide low-cost treatment alternatives under mild conditions for such contained wastes, we have proposed to use the radiation-resistant bacterium, Deinococcus radiodurans. This project has focused on developing D. radiodurans strains for dual purpose processes: cometabolic treatment of haloorganics and other solvents and removal of heavy metals from waste streams in an above-ground reactor system. The characteristics of effective treatment strains that must be attained are: (a) high biodegradative and metal binding activity; (b) stable treatment characteristics in the absence of selection and in the presence of physiological stress; (c) survival and activity under harsh chemical conditions, including radiation. The result of this project has been a suite of strains with high biodegradative capabilities that are candidates for pilot stage treatment systems. In addition, we have determined how to create conditions to precipitate heavy metals on the surface of the bacterium, as the first step towards creating dual-use treatment strains for contained mixed wastes of importance to the DOE. Finally, we have analyzed stress response in this bacterium, to create the foundation for developing treatment processes that maximize degradation while optimizing survival under high stress conditions.

  8. Programmed cell death in Laminaria japonica (Phaeophyta) tissues infected with alginic acid decomposing bacterium

    Institute of Scientific and Technical Information of China (English)

    WANG Gaoge; LIN Wei; ZHANG Lijing; YAN Xiaojun; DUAN Delin

    2004-01-01

    TdT-mediated dUTP-biotin nick end labeling (TUNEL) is a sensitive and valid method for detecting DNA cleavage in programmed cell death (PCD). Using this method, DNA cleavage was observed in Laminaria japonica sporophytic tissues, which were infected with alginic acid decomposing bacterium. It was found that DNA cleavage occurred 5 min after the infection, the fragments with 3′-OH groups of cleaved nuclear DNA increased with time of infection and spread from the infection site. Although no typical DNA ladder (200 bp/180 bp) was detected by routine agarose gel electrophoresis, the cleavage of nuclear DNA fragments of 97~48.5 kb could be detected by pulsed field gel electrophoresis (PFGE). By using CaspGLOWTM fluorescein active caspase-3 staining method, caspase-3 activity has been detected in response to the infection of alginic acid decomposing bacterium. Our results are similar to the observations in hypersensitive response (HR) of higher plant, suggesting that the rapid cell death of L. Japonica infected by alginic acid decomposing bacterium might be involved in PCD, and indicating that the occurrence of PCD is an active defense process against the pathogen's infection.

  9. Phosphate enhances levan production in the endophytic bacterium Gluconacetobacter diazotrophicus Pal5.

    Science.gov (United States)

    Idogawa, Nao; Amamoto, Ryuta; Murata, Kousaku; Kawai, Shigeyuki

    2014-01-01

    Gluconacetobacter diazotrophicus is a gram-negative and endophytic nitrogen-fixing bacterium that has several beneficial effects in host plants; thus, utilization of this bacterium as a biofertilizer in agriculture may be possible. G. diazotrophicus synthesizes levan, a D-fructofuranosyl polymer with β-(2→6) linkages, as an exopolysaccharide and the synthesized levan improves the stress tolerance of the bacterium. In this study, we found that phosphate enhances levan production by G. diazotrophicus Pal5, a wild type strain that showed a stronger mucous phenotype on solid medium containing 28 mM phosphate than on solid medium containing 7 mM phosphate. A G. diazotrophicus Pal5 levansucrase disruptant showed only a weak mucous phenotype regardless of the phosphate concentration, indicating that the mucous phenotype observed on 28 mM phosphate medium was caused by levan. To our knowledge, this is the first report of the effect of a high concentration of phosphate on exopolysaccharide production. PMID:24717418

  10. The effect of Pseudoxanthomonas sp. as manganese oxidizing bacterium on the corrosion behavior of carbon steel

    Energy Technology Data Exchange (ETDEWEB)

    Ashassi-Sorkhabi, H., E-mail: habib_ashassi@yahoo.com [Electrochemistry Research Laboratory, Physical Chemistry Department, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of); Moradi-Haghighi, M. [Electrochemistry Research Laboratory, Physical Chemistry Department, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of); Zarrini, G. [Microbiology laboratory, Biology Department, Science Faculty, University of Tabriz, Tabriz (Iran, Islamic Republic of)

    2012-02-01

    The present study investigated the role of manganese oxidizing bacterium (MOB), namely Pseudoxanthomonas sp. on the corrosion behavior of carbon steel. This bacterium was isolated from sewage treatment plants and identified by biochemical and molecular methods. The electrochemical techniques such as open circuit potentiometry, electrochemical impedance spectroscopy, potentiodynamic and cyclic polarization were used to measure the corrosion rate and observe the corrosion mechanism. Also, scanning electron microscopy and X-ray diffraction studies were applied to surface analysis. This study revealed the strong adhesion of the biofilm on the metal surface in the presence of Pseudoxanthomonas sp. that enhanced the corrosion of carbon steel. X-ray diffraction patterns identified a high content of MnO{sub 2} deposition within these biofilms. This is the first report that discloses the involvement of Pseudoxanthomonas sp. as manganese oxidizing bacteria on the corrosion of carbon steel. - Highlights: Black-Right-Pointing-Pointer A new type of manganese oxidizing bacteria, namely Pseudoxanthomonas sp. was indicated. Black-Right-Pointing-Pointer This bacterium can create a biofilm on the part of metal surface and affect localized corrosion. Black-Right-Pointing-Pointer In the presence of biofilm, the diffusion of oxygen vacancies and manganese ions has occurred.

  11. Studies on culture condition of new marine bacterium Zooshikella sp. SY01

    Institute of Scientific and Technical Information of China (English)

    Wenjian LAN; Linfeng MO; Chuanghua CAI; Yipin ZHOU; Junhua YAO; Houjin LI

    2008-01-01

    New marine bacterium Zooshikella sp. SY01, producer of prodigiosin, was isolated from the seawaters of Sanya Bay. The culture conditions of this bacterium were investigated. Zooshikella sp. SY01 was cultured in 2216E media which contained tryptophan, histidine, lac-tonic acid, camphor, limonene, casein, diphenyl guani-dine, coumarin and 1,3-dinitrobenzene, respectively. After 5 days cultivation, the extracts of different culture broths were detected by direct infusion mass spectroscopy using positive ESI mode. As the results, tryptophan, his-tidine and casein didn't show any observable influences on the biosynthesis of prodigiosin. Lactonic acid, camphor, limonene, diphenyl guanidine, coumarin could inhibit the bacterium growth and prodigiosin biosynthesis to a cer-tain extent, slower the culture broth to turn red. However, 1, 3-dinitrobenzene inhibited the bacteria to produce pro-digiosin completely. MS data suggested that various metabolites with chemodiversity were produced in differ-ent culture media. In particular, a series of high-molecu-lar-weight compounds with high relative abundances were observed in the medium containing limonene. To further optimize the culture condition, more new prodigiosin ana-logues and lead compounds can be obtained and the goal of "one strain-many compounds" can be achieved.

  12. Genetic Engineering of a Radiation-Resistant Bacterium for Biodegradation of Mixed Wastes. Final Report

    International Nuclear Information System (INIS)

    Aqueous mixed low level wastes (MLLW) containing radionuclides, solvents, and/or heavy metals represent a serious current and future problem for DOE environmental management and cleanup. In order to provide low-cost treatment alternatives under mild conditions for such contained wastes, we have proposed to use the radiation-resistant bacterium, Deinococcus radiodurans. This project has focused on developing D. radiodurans strains for dual purpose processes: cometabolic treatment of haloorganics and other solvents and removal of heavy metals from waste streams in an above-ground reactor system. The characteristics of effective treatment strains that must be attained are: (a) high biodegradative and metal binding activity; (b) stable treatment characteristics in the absence of selection and in the presence of physiological stress; (c) survival and activity under harsh chemical conditions, including radiation. The result of this project has been a suite of strains with high biodegradative capabilities that are candidates for pilot stage treatment systems. In addition, we have determined how to create conditions to precipitate heavy metals on the surface of the bacterium, as the first step towards creating dual-use treatment strains for contained mixed wastes of importance to the DOE. Finally, we have analyzed stress response in this bacterium, to create the foundation for developing treatment processes that maximize degradation while optimizing survival under high stress conditions

  13. The effect of Pseudoxanthomonas sp. as manganese oxidizing bacterium on the corrosion behavior of carbon steel

    International Nuclear Information System (INIS)

    The present study investigated the role of manganese oxidizing bacterium (MOB), namely Pseudoxanthomonas sp. on the corrosion behavior of carbon steel. This bacterium was isolated from sewage treatment plants and identified by biochemical and molecular methods. The electrochemical techniques such as open circuit potentiometry, electrochemical impedance spectroscopy, potentiodynamic and cyclic polarization were used to measure the corrosion rate and observe the corrosion mechanism. Also, scanning electron microscopy and X-ray diffraction studies were applied to surface analysis. This study revealed the strong adhesion of the biofilm on the metal surface in the presence of Pseudoxanthomonas sp. that enhanced the corrosion of carbon steel. X-ray diffraction patterns identified a high content of MnO2 deposition within these biofilms. This is the first report that discloses the involvement of Pseudoxanthomonas sp. as manganese oxidizing bacteria on the corrosion of carbon steel. - Highlights: ► A new type of manganese oxidizing bacteria, namely Pseudoxanthomonas sp. was indicated. ► This bacterium can create a biofilm on the part of metal surface and affect localized corrosion. ► In the presence of biofilm, the diffusion of oxygen vacancies and manganese ions has occurred.

  14. Antagonism and Molecular Identification of an Antibiotic Bacterium BS04 Against Phytopathogenic Fungi and Bacteria

    Institute of Scientific and Technical Information of China (English)

    Xie Jing(谢晶); Ge Shaorong; Tao Yong; Gao Ping; Liu Kun; Liu Shigui

    2004-01-01

    Through a modified agar well diffusion assay, antagonism of bacterium BS04 is tested. The data show that BS04 has antibiotic activity against phytopathogenic fungi and bacteria, including Phoma wasabiae Yokogi, Cochlibolus Heterostrophu, Exserohilum Turcicum, Curuvularia Lunata (Walk) Boed, Thantephorus cucumris, Fusarium graminearum, Xanthomonas axonopodis pv. Citri (Hasse) Dye and Xanthomonas zingiberi (Uyeda) Savulescu. The products of bacterium BS04 can endure the treatment of a wide range of pH, and maintain the antibiotic activity after treatment of 100℃ for 30 min. The result suggests that bacterium BS04 has the potential as a promising biocontrol agent. In order to determine the taxonomic placement, the molecular identification of BS04 is performed. The comparative analysis of 16s rDNA sequences indicates that the 16s rDNA sequence of BS04 is highly homologous with sequences of typical Paenibacillus bacteria from the RPD library (from 92% to 99%). And the constructed phylogenetic tree by using maximum-likelihood method with Bootstrap Trial 1000 proves that BS04 is subjected to Paenibacillus polymyxa.

  15. Anomalous magnetic orientations of magnetosome chains in a magnetotactic bacterium: Magnetovibrio blakemorei strain MV-1.

    Directory of Open Access Journals (Sweden)

    Samanbir S Kalirai

    Full Text Available There is a good deal of published evidence that indicates that all magnetosomes within a single cell of a magnetotactic bacterium are magnetically oriented in the same direction so that they form a single magnetic dipole believed to assist navigation of the cell to optimal environments for their growth and survival. Some cells of the cultured magnetotactic bacterium Magnetovibrio blakemorei strain MV-1 are known to have relatively wide gaps between groups of magnetosomes that do not seem to interfere with the larger, overall linear arrangement of the magnetosomes along the long axis of the cell. We determined the magnetic orientation of the magnetosomes in individual cells of this bacterium using Fe 2p X-ray magnetic circular dichroism (XMCD spectra measured with scanning transmission X-ray microscopy (STXM. We observed a significant number of cases in which there are sub-chains in a single cell, with spatial gaps between them, in which one or more sub-chains are magnetically polarized opposite to other sub-chains in the same cell. These occur with an estimated frequency of 4.0±0.2%, based on a sample size of 150 cells. We propose possible explanations for these anomalous cases which shed insight into the mechanisms of chain formation and magnetic alignment.

  16. The Role of Exopolymers in Protection of Ralstonia sp., a Cadmium-resistant Bacterium, from Cadmium Toxicity

    OpenAIRE

    Anchulee Watcharamusik; Benjaphorn Prapagdee

    2008-01-01

    Production of exopolymers is one of heavy metal resistance mechanisms in bacteria. Ralstonia sp. TAK1, a cadmium-resistant bacterium, was isolated from a high cadmium (Cd) contaminated soil at the zinc mine, Tak province, Thailand. The bacterium was cultivated in LB broth and its growth was monitored. The yields of exopolymers were measured by the phenol-sulfuric method at different growth phases. The levels of Cd resistance were quantitatively determined by survival cell assay. The highest a...

  17. Photoproduction of hydrogen by a non-sulphur bacterium isolated from root zones of water fern Azolla pinnata

    Energy Technology Data Exchange (ETDEWEB)

    Singh, S.P.; Srivastava, S.C.; Pandey, K.D. (Banaras Hindu Univ., Varanasi (IN). Centre of Advanced Study in Botany)

    1990-01-01

    A photosynthetic bacterium Rhodopseudomonas sp. BHU strain 1 was isolated from the root zone of water fern Azolla pinnata. The bacterium was found to produce hydrogen with potato starch under phototrophic conditions. The immobilized bacterial cells showed sustained hydrogen production with a more than 4-fold difference over free cell suspensions. The data have been discussed in the light of possible utilization of relatively cheaper raw materials by non-sulphur bacteria to evolve hydrogen. (author).

  18. Effect of arsenite-oxidizing bacterium B. laterosporus on arsenite toxicity and arsenic translocation in rice seedlings.

    Science.gov (United States)

    Yang, Gui-Di; Xie, Wan-Ying; Zhu, Xi; Huang, Yi; Yang, Xiao-Jun; Qiu, Zong-Qing; Lv, Zhen-Mao; Wang, Wen-Na; Lin, Wen-Xiong

    2015-10-01

    Arsenite [As (III)] oxidation can be accelerated by bacterial catalysis, but the effects of the accelerated oxidation on arsenic toxicity and translocation in rice plants are poorly understood. Herein we investigated how an arsenite-oxidizing bacterium, namely Brevibacillus laterosporus, influences As (III) toxicity and translocation in rice plants. Rice seedlings of four cultivars, namely Guangyou Ming 118 (GM), Teyou Hang II (TH), Shanyou 63 (SY) and Minghui 63 (MH), inoculated with or without the bacterium were grown hydroponically with As (III) to investigate its effects on arsenic toxicity and translocation in the plants. Percentages of As (III) oxidation in the solutions with the bacterium (100%) were all significantly higher than those without (30-72%). The addition of the bacterium significantly decreased As (III) concentrations in SY root, GM root and shoot, while increased the As (III) concentrations in the shoot of SY, MH and TH and in the root of MH. Furthermore, the As (III) concentrations in the root and shoot of SY were both the lowest among the treatments with the bacterium. On the other hand, its addition significantly alleviated the As (III) toxicity on four rice cultivars. Among the treatments amended with B. laterosporus, the bacterium showed the best remediation on SY seedlings, with respect to the subdued As (III) toxicity and decreased As (III) concentration in its roots. These results indicated that As (III) oxidation accelerated by B. laterosporus could be an effective method to alleviate As (III) toxicity on rice seedlings.

  19. Polaribacter gen. nov., with three new species, P. irgensii sp. nov., P. franzmannii sp. nov. and P. filamentus sp. nov., gas vacuolate polar marine bacteria of the Cytophaga-Flavobacterium-Bacteroides group and reclassification of 'Flectobacillus glomeratus' as Polaribacter glomeratus comb. nov

    Science.gov (United States)

    Gosink, J. J.; Woese, C. R.; Staley, J. T.

    1998-01-01

    Several psychrophilic, gas vacuolate strains of the Cytophage-Flavobacterium-Bacteroides (CFB) phylogenetic group were isolated from sea ice and water from the Arctic and the Antarctic. The closest taxonomically defined species by 16S rRNA sequence analysis is 'Flectobacillus glomeratus'. However, 'Flc. glomeratus' is phylogenetically distant from the Flectobacillus type species, Flc. major. On the basis of phenotypic, genotypic and 16S rRNA sequence analyses we propose a new genus, Polaribacter, with three new species, Polaribacter irgensii strain 23-P (ATCC 700398), Polaribacter franzmannii strain 301 (ATCC 700399) and Polaribacter filamentus strain 215 (ATCC 700397). P. filamentus is the type species of the genus. None of these species exhibits a cosmopolitan or bipolar distribution. This is the first taxonomic description of gas vacuolate bacteria in the CFB group. Additionally, we propose that 'Flc. glomeratus' be reclassified to the genus Polaribacter as P. glomeratus, comb. nov.

  20. Iron acquisition mechanisms of Flavobacterium psychrophilum

    DEFF Research Database (Denmark)

    Møller, Jeannette Dan; Ellis, A.E.; Barnes, A.C.;

    2005-01-01

    strains and was lacking from negative strains. While a weak catechol reaction was detectable in CAS+ culture supernatants, the CAS reaction was, to some extent, heat sensitive, questioning whether the positive reaction was caused only by siderophores. The ability to grow in vitro under iron......-restricted conditions did not correlate with the CAS reactivity, as growth of both CAS+ and CAS- strains was similarly impaired under iron restriction induced by 2,2 dipyridyl. Suppressed growth under these conditions was restored by addition of FeCl3, haemoglobin and transferrin for both CAS+ and CAS- strains...

  1. Cloning and characterization of nif structural and regulatory genes in the purple sulfur bacterium, Halorhodospira halophila.

    Science.gov (United States)

    Tsuihiji, Hisayoshi; Yamazaki, Yoichi; Kamikubo, Hironari; Imamoto, Yasushi; Kataoka, Mikio

    2006-03-01

    Halorhodospira halophila is a halophilic photosynthetic bacterium classified as a purple sulfur bacterium. We found that H. halophila generates hydrogen gas during photoautotrophic growth as a byproduct of a nitrogenase reaction. In order to consider the applied possibilities of this photobiological hydrogen generation, we cloned and characterized the structural and regulatory genes encoding the nitrogenase, nifH, nifD and nifA, from H. halophila. This is the first description of the nif genes for a purple sulfur bacterium. The amino-acid sequences of NifH and NifD indicated that these proteins are an Fe protein and a part of a MoFe protein, respectively. The important residues are conserved completely. The sequence upstream from the nifH region and sequence similarities of nifH and nifD with those of the other organisms suggest that the regulatory system might be a NifL-NifA system; however, H. halophila lacks nifL. The amino-acid sequence of H. halophila NifA is closer to that of the NifA of the NifL-NifA system than to that of NifA without NifL. H. halophila NifA does not conserve either the residue that interacts with NifL or the important residues involved in NifL-independent regulation. These results suggest the existence of yet another regulatory system, and that the development of functional systems and their molecular counterparts are not necessarily correlated throughout evolution. All of these Nif proteins of H. halophila possess an excess of acidic residues, which acts as a salt-resistant mechanism.

  2. Treatment of Alkaline Cr(VI)-Contaminated Leachate with an Alkaliphilic Metal-Reducing Bacterium.

    Science.gov (United States)

    Watts, Mathew P; Khijniak, Tatiana V; Boothman, Christopher; Lloyd, Jonathan R

    2015-08-15

    Chromium in its toxic Cr(VI) valence state is a common contaminant particularly associated with alkaline environments. A well-publicized case of this occurred in Glasgow, United Kingdom, where poorly controlled disposal of a cementitious industrial by-product, chromite ore processing residue (COPR), has resulted in extensive contamination by Cr(VI)-contaminated alkaline leachates. In the search for viable bioremediation treatments for Cr(VI), a variety of bacteria that are capable of reduction of the toxic and highly soluble Cr(VI) to the relatively nontoxic and less mobile Cr(III) oxidation state, predominantly under circumneutral pH conditions, have been isolated. Recently, however, alkaliphilic bacteria that have the potential to reduce Cr(VI) under alkaline conditions have been identified. This study focuses on the application of a metal-reducing bacterium to the remediation of alkaline Cr(VI)-contaminated leachates from COPR. This bacterium, belonging to the Halomonas genus, was found to exhibit growth concomitant to Cr(VI) reduction under alkaline conditions (pH 10). Bacterial cells were able to rapidly remove high concentrations of aqueous Cr(VI) (2.5 mM) under anaerobic conditions, up to a starting pH of 11. Cr(VI) reduction rates were controlled by pH, with slower removal observed at pH 11, compared to pH 10, while no removal was observed at pH 12. The reduction of aqueous Cr(VI) resulted in the precipitation of Cr(III) biominerals, which were characterized using transmission electron microscopy and energy-dispersive X-ray analysis (TEM-EDX) and X-ray photoelectron spectroscopy (XPS). The effectiveness of this haloalkaliphilic bacterium for Cr(VI) reduction at high pH suggests potential for its use as an in situ treatment of COPR and other alkaline Cr(VI)-contaminated environments. PMID:26048926

  3. Pontibacter diazotrophicus sp. nov., a novel nitrogen-fixing bacterium of the family Cytophagaceae.

    Directory of Open Access Journals (Sweden)

    Linghua Xu

    Full Text Available Few diazotrophs have been found to belong to the family Cytophagaceae so far. In the present study, a Gram-negative, rod-shaped bacterium that forms red colonies, was isolated from sands of the Takalamakan desert. It was designated H4XT. Phylogenetic and biochemical analysis indicated that the isolate is a new species of the genus Pontibacter. The 16S rRNA gene of H4XT displays 94.2-96.8% sequence similarities to those of other strains in Pontibacter. The major respiratory quinone is menaquinone-7 (MK-7. The DNA G+C content is 46.6 mol%. The major cellular fatty acids are iso-C15∶0, C16∶1ω5c, summed feature 3 (containing C16∶1ω6c and/or C16∶1ω7c and summed feature 4 (comprising anteiso-C17∶1B and/or iso-C17∶1I. The major polar lipids are phosphatidylethanolamine (PE, one aminophospholipid (APL and some unknown phospholipids (PLs. It is interesting to see that this bacterium can grow very well in a nitrogen-free medium. PCR amplification suggested that the bacterium possesses at least one type of nitrogenase gene. Acetylene reduction assay showed that H4XT actually possesses nitrogen-fixing activity. Therefore, it can be concluded that H4XT is a new diazotroph. We thus referred it to as Pontibacter diazotrophicus sp. nov. The type strain is H4XT ( = CCTCC AB 2013049T = NRRL B-59974T.

  4. Biochemical Analyses of Multiple Endoxylanases from the Rumen Bacterium Ruminococcus albus 8 and Their Synergistic Activities with Accessory Hemicellulose-Degrading Enzymes ▿ †

    OpenAIRE

    Moon, Young Hwan; Iakiviak, Michael; Bauer, Stefan; Roderick I. Mackie; Cann, Isaac K. O.

    2011-01-01

    Ruminococcus albus 8 is a ruminal bacterium capable of metabolizing hemicellulose and cellulose, the major components of the plant cell wall. The enzymes that allow this bacterium to capture energy from the two polysaccharides, therefore, have potential application in plant cell wall depolymerization, a process critical to biofuel production. For this purpose, a partial genome sequence of R. albus 8 was generated. The genomic data depicted a bacterium endowed with multiple forms of plant cell...

  5. Leucyl-tRNA synthetase from the ancestral bacterium Aquifex aeolicus contains relics of synthetase evolution

    OpenAIRE

    Zhao, Ming-Wei; Zhu, Bin; Hao, Rui; Xu, Min-Gang; Eriani, Gilbert; Wang, En-Duo

    2005-01-01

    The editing reactions catalyzed by aminoacyl-tRNA synthetases are critical for the faithful protein synthesis by correcting misactivated amino acids and misaminoacylated tRNAs. We report that the isolated editing domain of leucyl-tRNA synthetase from the deep-rooted bacterium Aquifex aeolicus (αβ-LeuRS) catalyzes the hydrolytic editing of both mischarged tRNALeu and minihelixLeu. Within the domain, we have identified a crucial 20-amino-acid peptide that confers editing capacity when transplan...

  6. Biodegradation of bisphenol A and other bisphenols by a gram-negative aerobic bacterium.

    OpenAIRE

    Lobos, J. H.; Leib, T K; Su, T. M.

    1992-01-01

    A novel bacterium designated strain MV1 was isolated from a sludge enrichment taken from the wastewater treatment plant at a plastics manufacturing facility and shown to degrade 2,2-bis(4-hydroxyphenyl)propane (4,4'-isopropylidenediphenol or bisphenol A). Strain MV1 is a gram-negative, aerobic bacillus that grows on bisphenol A as a sole source of carbon and energy. Total carbon analysis for bisphenol A degradation demonstrated that 60% of the carbon was mineralized to CO2, 20% was associated...

  7. Exoelectrogenic bacterium phylogenetically related to Citrobacter freundii, isolated from anodic biofilm of a microbial fuel cell.

    Science.gov (United States)

    Huang, Jianjian; Zhu, Nengwu; Cao, Yanlan; Peng, Yue; Wu, Pingxiao; Dong, Wenhao

    2015-02-01

    An electrogenic bacterium, named Citrobacter freundii Z7, was isolated from the anodic biofilm of microbial fuel cell (MFC) inoculated with aerobic sewage sludge. Cyclic voltammetry (CV) analysis exhibited that the strain Z7 had relatively high electrochemical activity. When the strain Z7 was inoculated into MFC, the maximum power density can reach 204.5 mW/m(2) using citrate as electron donor. Series of substrates including glucose, glycerol, lactose, sucrose, and rhammose could be utilized to generate power. CV tests and the addition of anode solution as well as AQDS experiments indicated that the strain Z7 might transfer electrons indirectly via secreted mediators.

  8. Coarse grained simulation reveals antifreeze properties of hyperactive antifreeze protein from Antarctic bacterium Colwellia sp.

    Science.gov (United States)

    Nguyen, Hung; Van, Thanh Dac; Le, Ly

    2015-10-01

    The novel hyperactive antifreeze protein (AFP) of Antarctic sea ice bacterium Colwellia sp. provides a target for studying the protection of psychrophilic microgoranisms against freezing environment. Interestingly, the Colwellia sp. hyperactive antifreeze protein (ColAFP) was crystallized without the structural dynamic characteristics. Here, the result indicated, through coarse grained simulation of ColAFP under various subfreezing temperature, that ColAFP remains active at temperature of equal and greater than 275 K (∼2 °C). Extensive simulation analyses also revealed the adaptive mechanism of ColAFP in subfreezing environment. Our result provides a structural dynamic understanding of the ColAFP.

  9. Response to Comments on "A Bacterium That Can Grow Using Arsenic Instead of Phosphorus"

    Energy Technology Data Exchange (ETDEWEB)

    Wolfe-Simon, F; Blum, J S; Kulp, T R; Gordon, G W; Hoeft, S E; Pett-Ridge, J; Stolz, J F; Webb, S M; Weber, P K; Davies, P W; Anbar, A D; Oremland, R S

    2011-03-07

    Concerns have been raised about our recent study describing a bacterium that can grow using arsenic (As) instead of phosphorus (P). Our data suggested that As could act as a substitute for P in major biomolecules in this organism. Although the issues raised are of investigative interest, we contend that they do not invalidate our conclusions. We argue that while no single line of evidence we presented was sufficient to support our interpretation of the data, taken as an entire dataset we find no plausible alternative to our conclusions. Here we reply to the critiques and provide additional arguments supporting the assessment of the data we reported.

  10. A bacterium that can grow by using arsenic instead of phosphorus

    Energy Technology Data Exchange (ETDEWEB)

    Wolfe-Simon, F; Blum, J S; Kulp, T R; Gordon, G W; Hoeft, S E; Pett-Ridge, J; Stolz, J F; Webb, S M; Weber, P K; Davies, P W; Anbar, A D; Oremland, R S

    2010-11-01

    Life is mostly composed of the elements carbon, hydrogen, nitrogen, oxygen, sulfur and phosphorus. Although these six elements make up nucleic acids, proteins and lipids and thus the bulk of living matter, it is theoretically possible that some other elements in the periodic table could serve the same functions. Here we describe a bacterium, strain GFAJ-1 of the Halomonadaceae, isolated from Mono Lake, CA, which substitutes arsenic for phosphorus to sustain its growth. Our data show evidence for arsenate in macromolecules that normally contain phosphate, most notably nucleic acids and proteins. Exchange of one of the major bio-elements may have profound evolutionary and geochemical significance.

  11. Improved manganese-oxidizing activity of DypB, a peroxidase from a lignolytic bacterium

    OpenAIRE

    Singh, Rahul; Grigg, Jason C.; Qin, Wei; Kadla, John F.; Murphy, Michael E. P.; Eltis, Lindsay D.

    2013-01-01

    DypB, a dye-decolorizing peroxidase from the lignolytic soil bacterium Rhodococcus jostii RHA1, catalyzes the peroxide-dependent oxidation of divalent manganese (Mn2+), albeit less efficiently than fungal manganese peroxidases. Substitution of Asn246, a distal heme residue, with alanine, increased the enzyme’s apparent kcat and kcat/Km values for Mn2+ by 80- and 15-fold, respectively. A 2.2 Å resolution X-ray crystal structure of the N246A variant revealed the Mn2+ to be bound within a pocket...

  12. Genome sequence of the marine bacterium Corynebacterium maris type strain Coryn-1T (= DSM 45190T)

    OpenAIRE

    Schaffert, Lena; Albersmeier, Andreas; Bednarz, Hanna; Niehaus, Karsten; Kalinowski, Jörn; Rückert, Christian

    2013-01-01

    Corynebacterium maris Coryn-1T Ben-Dov et al. 2009 is a member of the genus Corynebacterium which contains Gram-positive, non-spore forming bacteria with a high G+C content. C. maris was isolated from the mucus of the Scleractinian coral Fungia granulosa and belongs to the aerobic and non-haemolytic corynebacteria. It displays tolerance to salts (up to 10%) and is related to the soil bacterium Corynebacterium halotolerans . As this is a type strain in a subgroup of Corynebacterium without com...

  13. Complete Genome Sequence of the Filamentous Anoxygenic Phototrophic Bacterium Chloroflexus aurantiacus

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Kuo-Hsiang [Washington University, St. Louis; Barry, Kerrie [U.S. Department of Energy, Joint Genome Institute; Chertkov, Olga [Los Alamos National Laboratory (LANL); Dalin, Eileen [U.S. Department of Energy, Joint Genome Institute; Han, Cliff [Los Alamos National Laboratory (LANL); Hauser, Loren John [ORNL; Honchak, Barbara M [Washington University, St. Louis; Karbach, Lauren E [Washington University, St. Louis; Land, Miriam L [ORNL; Lapidus, Alla L. [Joint Genome Institute, Walnut Creek, California; Larimer, Frank W [ORNL; Mikhailova, Natalia [U.S. Department of Energy, Joint Genome Institute; Pitluck, Sam [Joint Genome Institute, Walnut Creek, California; Pierson, Beverly K [University of Puget Sound, Tacoma, WA

    2011-01-01

    Chloroflexus aurantiacus is a thermophilic filamentous anoxygenic phototrophic (FAP) bacterium, and can grow phototrophically under anaerobic conditions or chemotrophically under aerobic and dark conditions. According to 16S rRNA analysis, Chloroflexi species are the earliest branching bacteria capable of photosynthesis, and Cfl. aurantiacus has been long regarded as a key organism to resolve the obscurity of the origin and early evolution of photosynthesis. Cfl. aurantiacus contains a chimeric photosystem that comprises some characters of green sulfur bacteria and purple photosynthetic bacteria, and also has some unique electron transport proteins compared to other photosynthetic bacteria.

  14. Dynamic detection of a single bacterium: nonlinear rotation rate shifts of driven magnetic microsphere stages

    CERN Document Server

    McNaughton, B H; Kopelman, R; Agayan, Rodney R.; Kopelman, Raoul; Naughton, Brandon H. Mc

    2006-01-01

    We report on a new technique which was used to detect single Escherichia coli that is based on the changes in the nonlinear rotation of a magnetic microsphere driven by an external magnetic field. The presence of one Escherichia Coli bacterium on the surface of a 2.0 micron magnetic microsphere caused an easily measurable change in the drag of the system and, therefore, in the nonlinear rotation rate. The straight-forward measurement uses standard microscopy techniques and the observed average shift in the nonlinear rotation rate changed by a factor of ~3.8.

  15. Characterization of Two New Glycosyl Hydrolases from the Lactic Acid Bacterium Carnobacterium piscicola Strain BA

    OpenAIRE

    Coombs, Jonna; Brenchley, Jean E.

    2001-01-01

    Three genes with homology to glycosyl hydrolases were detected on a DNA fragment cloned from a psychrophilic lactic acid bacterium isolate, Carnobacterium piscicola strain BA. A 2.2-kb region corresponding to an α-galactosidase gene, agaA, was followed by two genes in the same orientation, bgaB, encoding a 2-kb β-galactosidase, and bgaC, encoding a structurally distinct 1.76-kb β-galactosidase. This gene arrangement had not been observed in other lactic acid bacteria, including Lactococcus la...

  16. Genome Sequence of the Boron-Tolerant and -Requiring Bacterium Bacillus boroniphilus

    OpenAIRE

    ÇÖL, Bekir; Özkeserli, Zeynep; Kumar, Dibyendu; ÖZDAĞ, Hilal; Alakoç, Yeşim D.

    2014-01-01

    Bacillus boroniphilus is a highly boron-tolerant bacterium that also requires this element for its growth. The complete genome sequence of B. boroniphilus was determined by a combination of shotgun sequencing and paired-end sequencing using 454 pyrosequencing technology. A total of 84,872,624 reads from shotgun sequencing and a total of 194,092,510 reads from paired-end sequencing were assembled using Newbler 2.3. The estimated size of the draft genome is 5.2 Mb.

  17. Halomonas olivaria sp nov., a moderately halophilic bacterium isolated from olive-processing effluents

    OpenAIRE

    Amouric, A.; Liebgott, Pierre-Pol; Joseph, Manon; Brochier-Armanet, C; LORQUIN, Jean

    2014-01-01

    A moderately halophilic, Gram-stain-negative, non-sporulating bacterium designed as strain TYRC17(T) was isolated from olive-processing effluents. The organism was a straight rod, motile by means of peritrichous flagella and able to respire both oxygen and nitrate. Growth occurred with 0-25 % (w/v) NaCl (optimum, 7%), at pH 5-11 (optimum, pH 7.0) and at 4-50 degrees C (optimally at 35 degrees C). It accumulated poly-beta-hydroxyalkanoate granules and produced exopolysaccharides. The predomina...

  18. Sequencing and Characterization of the xyl Operon of a Gram-Positive Bacterium, Tetragenococcus halophila

    OpenAIRE

    TAKEDA, YASUO; Takase, Kazuma; Yamato, Ichiro; Abe, Keietsu

    1998-01-01

    The xyl operon of a gram-positive bacterium, Tetragenococcus halophila (previously called Pediococcus halophilus), was cloned and sequenced. The DNA was about 7.7 kb long and contained genes for a ribose binding protein and part of a ribose transporter, xylR (a putative regulatory gene), and the xyl operon, along with its regulatory region and transcription termination signal, in this order. The DNA was AT rich, the GC content being 35.8%, consistent with the GC content of this gram-positive ...

  19. Mageeibacillus indolicus gen. nov., sp. nov: A novel bacterium isolated from the female genital tract

    OpenAIRE

    Austin, Michele N.; Rabe, Lorna K.; Srinivasan, Sujatha; Fredricks, David N.; Wiesenfeld, Harold C.; Hillier, Sharon L.

    2014-01-01

    Three isolates of a bacterium recovered from human endometrium using conventional culture methods were characterized biochemically and subjected to 16S rRNA gene sequencing and phylogenetic analysis. Isolates were non-motile, obligately anaerobic, non-spore forming, asaccharolytic, non-cellulolytic, indole positive, Gram positive rods. Cell wall fatty acid profiling revealed C14:0, C16:0, C18:2 ω6, 9c, C18:1 ω9c and C18:0 to be the major fatty acid composition. The DNA mol % G+C was determine...

  20. Ercella succinigenes gen. nov., sp. nov., ananaerobic succinate-producing bacterium

    OpenAIRE

    Van Gelder, A.H.; Sousa, D.Z.; Rijpstra, W.I.C.; J. S. Sinninghe Damsté; Stams, A. J. M.; Sánchez-Andrea, I.

    2014-01-01

    A novel anaerobic succinate-producing bacterium, strain ZWBT, was isolated from sludge collected from a biogas desulfurization bioreactor (Eerbeek, The Netherlands). Cells were non-spore forming, motile, slightly curved rods (0.4 to 0.5 µm in diameter and 2 to 3 µm in length), and stained Gram-negative. The temperature range for growth was 25 to 40°C, with an optimum at 37°C. The pH range for growth was 7.0 to 9.0, with an optimum at pH 7.5. Strain ZWBT ferments glycerol and several carbohydr...

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

    International Nuclear Information System (INIS)

    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

  2. Whole genome shotgun sequence of Bacillus amyloliquefaciens TF28, a biocontrol entophytic bacterium.

    Science.gov (United States)

    Zhang, Shumei; Jiang, Wei; Li, Jing; Meng, Liqiang; Cao, Xu; Hu, Jihua; Liu, Yushuai; Chen, Jingyu; Sha, Changqing

    2016-01-01

    Bacillus amyloliquefaciens TF28 is a biocontrol endophytic bacterium that is capable of inhibition of a broad range of plant pathogenic fungi. The strain has the potential to be developed into a biocontrol agent for use in agriculture. Here we report the whole-genome shotgun sequence of the strain. The genome size of B. amyloliquefaciens TF28 is 3,987,635 bp which consists of 3754 protein-coding genes, 65 tandem repeat sequences, 47 minisatellite DNA, 2 microsatellite DNA, 63 tRNA, 7rRNA, 6 sRNA, 3 prophage and CRISPR domains. PMID:27688836

  3. Penetration of the Coral-Bleaching Bacterium Vibrio shiloi into Oculina patagonica

    OpenAIRE

    Banin, E.; Israely, T.; Kushmaro, A.; Y. Loya; Orr, E; Rosenberg, E

    2000-01-01

    Inoculation of the coral-bleaching bacterium Vibrio shiloi into seawater containing its host Oculina patagonica led to adhesion of the bacteria to the coral surface via a β-d-galactose receptor, followed by penetration of the bacteria into the coral tissue. The internalized V. shiloi cells were observed inside the exodermal layer of the coral by electron microscopy and fluorescence microscopy using specific anti-V. shiloi antibodies to stain the intracellular bacteria. At 29°C, 80% of the bac...

  4. Complete genome sequence of Enterobacter cloacae GGT036: a furfural tolerant soil bacterium.

    Science.gov (United States)

    Gong, Gyeongtaek; Um, Youngsoon; Park, Tai Hyun; Woo, Han Min

    2015-01-10

    Enterobacter cloacae is a facultative anaerobic bacterium to be an important cause of nosocomial infection. However, the isolated E. cloacae GGT036 showed higher furfural-tolerant cellular growth, compared to industrial relevant strains such as Escherichia coli and Corynebacterium glutamicum. Here, we report the complete genome sequence of E. cloacae GGT036 isolated from Mt. Gwanak, Seoul, Republic of Korea. The genomic DNA sequence of E. cloacae GGT036 will provide valuable genetic resources for engineering of industrially relevant strains being tolerant to cellular inhibitors present in lignocellulosic hydrolysates.

  5. Clostridium peptidivorans sp. nov., a peptide-fermenting bacterium from an olive mill wastewater treatment digester

    OpenAIRE

    Mechichi, T.; Fardeau, Marie-Laure; Labat, Marc; Garcia, Jean-Louis; Verhé, F.; Patel, B.K.C.

    2000-01-01

    A new peptid-degrading, strictly anaerobic bacterium, designated strain TMC4T, was isolated from an olive mill wastewater treatment digester. Cells of strain TMC4T were motile, rod-shaped (5-10 x 0.6-1.2 microns), stained Gram-positive and formed terminal to subterminal spores that distended the cells. Optimal growth occurred at 37°C and pH 7 in an anaerobic basal medium containing 0.5% Casamino acids. Arginine, lysine, cysteine, methionine, histidine, serine, isoleucine, yeast extract, pepto...

  6. p-cresol methylhydroxylase from a denitrifying bacterium involved in anaerobic degradation of p-cresol.

    OpenAIRE

    Hopper, D. J.; Bossert, I D; Rhodes-Roberts, M E

    1991-01-01

    A bacterium, strain PC-07, previously isolated as part of a coculture capable of growing on p-cresol under anaerobic conditions with nitrate as the acceptor was identified as an Achromobacter sp. The first enzyme of the pathway, p-cresol methylhydroxylase, which converts its substrate into p-hydroxybenzyl alcohol, was purified. The enzyme had an Mr of 130,000 and the spectrum of a flavocytochrome. It was composed of flavoprotein subunits of Mr 54,000 and cytochrome subunits of Mr 12,500. The ...

  7. FACTORS LIMITING BACTERIAL GROWTH : III. CELL SIZE AND "PHYSIOLOGIC YOUTH" IN BACTERIUM COLI CULTURES.

    Science.gov (United States)

    Hershey, A D; Bronfenbrenner, J

    1938-07-20

    1. Measurements of the rate of oxygen uptake per cell in transplants of Bacterium coli from cultures of this organism in different phases of growth have given results in essential agreement with the observations of others. 2. Correlations of viable count, centrifugable nitrogen, and turbidity, with oxygen consumption, indicate that the increased metabolism during the early portion of the growth period is quantitatively referable to increased average size of cells. 3. Indirect evidence has suggested that the initial rate of growth of transplants is not related to the phase of growth of the parent culture.

  8. Aggregation of the rhizospheric bacterium Azospirillum brasilense in response to oxygen

    Science.gov (United States)

    Abdoun, Hamid; McMillan, Mary; Pereg, Lily

    2016-04-01

    Azospirillum brasilense spp. have ecological, scientific and agricultural importance. As model plant growth promoting rhizobacteria they interact with a large variety of plants, including important food and cash crops. Azospirillum strains are known for their production of plant growth hormones that enhance root systems and for their ability to fix nitrogen. Azospirillum cells transform in response to environmental cues. The production of exopolysaccharides and cell aggregation during cellular transformation are important steps in the attachment of Azospirillum to roots. We investigate signals that induce cellular transformation and aggregation in the Azospirillum and report on the importance of oxygen to the process of aggregation in this rhizospheric bacterium.

  9. Melanin from the nitrogen-fixing bacterium Azotobacter chroococcum: a spectroscopic characterization.

    Directory of Open Access Journals (Sweden)

    Aulie Banerjee

    Full Text Available Melanins, the ubiquitous hetero-polymer pigments found widely dispersed among various life forms, are usually dark brown/black in colour. Although melanins have variety of biological functions, including protection against ultraviolet radiation of sunlight and are used in medicine, cosmetics, extraction of melanin from the animal and plant kingdoms is not an easy task. Using complementary physicochemical techniques (i.e. MALDI-TOF, FTIR absorption and cross-polarization magic angle spinning solid-state (13C NMR, we report here the characterization of melanins extracted from the nitrogen-fixing non-virulent bacterium Azotobacter chroococcum, a safe viable source. Moreover, considering dihydroxyindole moiety as the main constituent, an effort is made to propose the putative molecular structure of the melanin hetero-polymer extracted from the bacterium. Characterization of the melanin obtained from Azotobacter chroococcum would provide an inspiration in extending research activities on these hetero-polymers and their use as protective agent against UV radiation.

  10. Economic game theory to model the attenuation of virulence of an obligate intracellular bacterium

    Directory of Open Access Journals (Sweden)

    Damian Tago

    2016-08-01

    Full Text Available Diseases induced by obligate intracellular pathogens have a large burden on global human and animal health. Understanding the factors involved in the virulence and fitness of these pathogens contributes to the development of control strategies against these diseases. Based on biological observations, a theoretical model using game theory is proposed to explain how obligate intracellular bacteria interact with their host. The equilibrium in such a game shows that the virulence and fitness of the bacterium is host-triggered and by changing the host’s defense system to which the bacterium is confronted, an evolutionary process leads to an attenuated strain. Although, the attenuation procedure has already been conducted in practice in order to develop an attenuated vaccine (e.g. with Ehrlichia ruminantium, there was a lack of understanding of the theoretical basis behind this process. Our work provides a model to better comprehend the existence of different phenotypes and some underlying evolutionary mechanisms for the virulence of obligate intracellular bacteria.

  11. Hyperthermostable and oxygen resistant hydrogenases from a hyperthermophilic bacterium Aquifex aeolicus: Physicochemical properties

    Energy Technology Data Exchange (ETDEWEB)

    Guiral, Marianne; Tron, Pascale; Belle, Valerie; Aubert, Corinne; Leger, Christophe; Guigliarelli, Bruno; Giudici-Orticoni, Marie-Therese [Laboratoire de Bioenergetique et Ingenierie des Proteines (BIP) IBSM, CNRS, 31 Chemin Joseph Aiguier, 13402 Marseille cedex 20 (France)

    2006-09-15

    The discovery of hydrogenases in hyperthermophiles has important ramifications not only in microbial physiology and evolution but also in biotechnologies. These organisms are the source of extremely stable enzymes (regarding temperature, pressure, and O{sub 2}). Aquifex aeolicus is a microaerophilic, hyperthermophilic bacterium containing three [NiFe] hydrogenases. It is the most hyperthermophilic bacterium known to date and grows at 85{sup o}C under a H{sub 2}/CO{sub 2}/O{sub 2} atmosphere. The Aquificales represent the earliest branching order of the bacterial domain indicating that they are the most ancient bacteria. Two Aquifex hydrogenases (one membrane-bound and one soluble) have been purified and characterized. In contrast to the majority of the [NiFe] hydrogenases, the hydrogenases from A. aeolicus are rather tolerant to oxygen. The molecular basis of the oxygen resistance of Aquifex hydrogenases has been investigated. The great stability of Aquifex hydrogenases with respect to oxygen and high temperatures make these enzymes good candidates for biotechnological uses. (author)

  12. Data supporting functional diversity of the marine bacterium Cobetia amphilecti KMM 296.

    Science.gov (United States)

    Balabanova, Larissa; Nedashkovskaya, Olga; Podvolotskaya, Anna; Slepchenko, Lubov; Golotin, Vasily; Belik, Alexey; Shevchenko, Ludmila; Son, Oksana; Rasskazov, Valery

    2016-09-01

    Data is presented in support of functionality of hyper-diverse protein families encoded by the Cobetia amphilecti KMM 296 (formerly Cobetia marina KMM 296) genome ("The genome of the marine bacterium Cobetia marina KMM 296 isolated from the mussel Crenomytilus grayanus (Dunker, 1853)" [1]) providing its nutritional versatility, adaptability and biocontrol that could be the basis of the marine bacterium evolutionary and application potential. Presented data include the information of growth and biofilm-forming properties of the food-associated isolates of Pseudomonas, Bacillus, Listeria, Salmonella and Staphylococcus under the conditions of their co-culturing with C. amphilecti KMM 296 to confirm its high inter-species communication and anti-microbial activity. Also included are the experiments on the crude petroleum consumption by C. amphilecti KMM 296 as the sole source of carbon in the presence of sulfate or nitrate to ensure its bioremediation capacity. The multifunctional C. amphilecti KMM 296 genome is a promising source for the beneficial psychrophilic enzymes and essential secondary metabolites. PMID:27508225

  13. Evaluation of nitrate removal by continuous culturing of an aerobic denitrifying bacterium, Paracoccus pantotrophus.

    Science.gov (United States)

    Hasegawa-Kurisu, K; Otani, Y; Hanaki, K

    2006-01-01

    Nitrate removal under aerobic conditions was investigated using pure cultures of Paracoccus pantotrophus, which is a well-known aerobic-denitrifying (AD) bacterium. When a high concentration of cultures with a high carbon/nitrogen (C/N) ratio was preserved at the beginning of batch experiments, subsequently added nitrate was completely removed. When continuous culturing was perpetuated, a high nitrate removal rate (66.5%) was observed on day 4 post-culture, although gradual decreases in AD ability with time were observed. The attenuation in AD ability was probably caused by carbon limitation, because when carbon concentration of inflow water was doubled, nitrate removal efficiency improved from 18.1% to 59.6%. Bacterial community analysis using the polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) method showed that P. pantotrophus disappeared in the suspended medium on day 8 post-culture, whereas other bacterial communities dominated by Acidovorax sp. appeared. Interestingly, this replaced bacterial community also showed AD ability. As P. pantotrophus was detected as attached colonies around the membrane and bottom of the reactor, this bacterium can therefore be introduced in a fixed form for treatment of wastewater containing nitrate with a high C/N ratio. PMID:17163031

  14. Non-specific immune response of bullfrog Rana catesbeiana to intraperitoneal injection of bacterium Aeromonas hydrophila

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Non-specific immune response of bullfrog Rana catesbeiana to pathogenic Aeromonas hydrophila was studied to 60 individuals in two groups. Each bullfrog in bacterium-injected group was injected intraperitoneally (i.p.) with 0.2 ml bacterial suspension at a density of 5.2 × 106 CFU/ml, while each one in control group injected i.p. with 0.2 ml sterile saline solution (0.85%, w/v). Three bullfrogs in both groups were sampled at 0, 1, 3, 7, 11, 15 and 20 days post-injection (dpi) for the evaluation of non-specific immune parameters. It was observed that intraperitoneal injection of A. hydrophila significantly increased the number of leucocytes and that of NBT-positive cells in peripheral blood. Significant increases in serum bactericidal activity and serum acid phosphatase activity were also observed in the bacterium-injected frogs when compared with those in the control group. However, a significant reduction was detected in vitro in phagocytosis activity of peripheral blood phagocytes. No significant difference in changes in the number of peripheral erythrocytes, serum superoxide dismutase (SOD) activity, and lysozyme activity was detected between the two groups. It is suggested that bullfrogs may produce a series of non-specific immune reactions in response to the A. hydrophila infection.

  15. (Per)chlorate reduction by an acetogenic bacterium, Sporomusa sp., isolated from an underground gas storage.

    KAUST Repository

    Balk, Melike

    2010-08-03

    A mesophilic bacterium, strain An4, was isolated from an underground gas storage reservoir with methanol as substrate and perchlorate as electron acceptor. Cells were Gram-negative, spore-forming, straight to curved rods, 0.5-0.8 microm in diameter, and 2-8 microm in length, growing as single cells or in pairs. The cells grew optimally at 37 degrees C, and the pH optimum was around 7. Strain An4 converted various alcohols, organic acids, fructose, acetoin, and H(2)/CO(2) to acetate, usually as the only product. Succinate was decarboxylated to propionate. The isolate was able to respire with (per)chlorate, nitrate, and CO(2). The G+C content of the DNA was 42.6 mol%. Based on the 16S rRNA gene sequence analysis, strain An4 was most closely related to Sporomusa ovata (98% similarity). The bacterium reduced perchlorate and chlorate completely to chloride. Key enzymes, perchlorate reductase and chlorite dismutase, were detected in cell-free extracts.

  16. Cold adaptation in the marine bacterium, Sphingopyxis alaskensis, assessed using quantitative proteomics.

    Science.gov (United States)

    Ting, Lily; Williams, Timothy J; Cowley, Mark J; Lauro, Federico M; Guilhaus, Michael; Raftery, Mark J; Cavicchioli, Ricardo

    2010-10-01

    The cold marine environment constitutes a large proportion of the Earth's biosphere. Sphingopyxis alaskensis was isolated as a numerically abundant bacterium from several cold marine locations, and has been extensively studied as a model marine bacterium. Recently, a metabolic labelling platform was developed to comprehensively identify and quantify proteins from S. alaskensis. The approach incorporated data normalization and statistical validation for the purpose of generating highly confident quantitative proteomics data. Using this approach, we determined quantitative differences between cells grown at 10°C (low temperature) and 30°C (high temperature). Cold adaptation was linked to specific aspects of gene expression: a dedicated protein-folding system using GroESL, DnaK, DnaJ, GrpE, SecB, ClpB and PPIase; polyhydroxyalkanoate-associated storage materials; a link between enzymes in fatty acid metabolism and energy generation; de novo synthesis of polyunsaturated fatty acids in the membrane and cell wall; inorganic phosphate ion transport by a phosphate import PstB homologue; TonB-dependent receptor and bacterioferritin in iron homeostasis; histidine, tryptophan and proline amino acid metabolism; and a large number of proteins without annotated functions. This study provides a new level of understanding on how important marine bacteria can adapt to compete effectively in cold marine environments. This study is also a benchmark for comparative proteomic analyses with other important marine bacteria and other cold-adapted organisms. PMID:20482592

  17. 趋磁细菌研究进展%Progress in studies on magnetotactic bacterium

    Institute of Scientific and Technical Information of China (English)

    孙秀兰; 刘伟伟; 张银志; 樊惠良; 陈文君

    2011-01-01

    Study on the magnetotactic bacterium in our country has a late start, with rare relevant reports.This paper mainly describes the research in this field at home and abroad, and the role of magnetotactic bacterium in food detection is also referred.The paper aims to help to promote the ongoing work in our country.It will lay a great basis for better development and utilization of this new environmental microorganism resources in the rapid and diversified detection methods of food.%趋磁细菌的研究在我国起步较晚,也少见有相关报道,本文主要介绍国内外这一领域的研究进展,并提到了趋磁细菌在食品检测中的应用,旨在促进国内此工作的开展,以便更好的开发利用这一新的环境微生物资源,为食品检测方法的快速化多样化奠定基础.

  18. Nitrite-Oxidizing Bacterium Nitrobacter winogradskyi Produces N-Acyl-Homoserine Lactone Autoinducers.

    Science.gov (United States)

    Mellbye, Brett L; Bottomley, Peter J; Sayavedra-Soto, Luis A

    2015-09-01

    Nitrobacter winogradskyi is a chemolithotrophic bacterium that plays a role in the nitrogen cycle by oxidizing nitrite to nitrate. Here, we demonstrate a functional N-acyl-homoserine lactone (acyl-HSL) synthase in this bacterium. The N. winogradskyi genome contains genes encoding a putative acyl-HSL autoinducer synthase (nwi0626, nwiI) and a putative acyl-HSL autoinducer receptor (nwi0627, nwiR) with amino acid sequences 38 to 78% identical to those in Rhodopseudomonas palustris and other Rhizobiales. Expression of nwiI and nwiR correlated with acyl-HSL production during culture. N. winogradskyi produces two distinct acyl-HSLs, N-decanoyl-l-homoserine lactone (C10-HSL) and a monounsaturated acyl-HSL (C10:1-HSL), in a cell-density- and growth phase-dependent manner, during batch and chemostat culture. The acyl-HSLs were detected by bioassay and identified by ultraperformance liquid chromatography with information-dependent acquisition mass spectrometry (UPLC-IDA-MS). The C=C bond in C10:1-HSL was confirmed by conversion into bromohydrin and detection by UPLC-IDA-MS.

  19. Microfabrication of patterns of adherent marine bacterium Phaeobacter inhibens using soft lithography and scanning probe lithography.

    Science.gov (United States)

    Zhao, Chuan; Burchardt, Malte; Brinkhoff, Thorsten; Beardsley, Christine; Simon, Meinhard; Wittstock, Gunther

    2010-06-01

    Two lithographic approaches have been explored for the microfabrication of cellular patterns based on the attachment of marine bacterium Phaeobacter inhibens strain T5. Strain T5 produces a new antibiotic that makes this bacterium potentially interesting for the pharmaceutical market and as a probiotic organism in aquacultures and in controlling biofouling. The microcontact printing (microCP) method is based on the micropatterning of self-assembled monolayers (SAMs) terminated with adhesive end groups such as CH(3) and COOH and nonadhesive groups (e.g., short oligomers of ethylene glycol (OEG)) to form micropatterned substrates for the adhesion of strain T5. The scanning probe lithographic method is based on the surface modification of OEG SAM by using a microelectrode, the probe of a scanning electrochemical microscope (SECM). Oxidizing agents (e.g., Br(2)) were electrogenerated in situ at the microelectrodes from Br(-) in aqueous solution to remove OEG SAMs locally, which allows the subsequent adsorption of bacteria. Various micropatterns of bacteria could be formed in situ on the substrate without a prefabricated template. The fabricated cellular patterns may be applied to a variety of marine biological studies that require the analysis of biofilm formation, cell-cell and cell-surface interactions, and cell-based biosensors and bioelectronics. PMID:20397716

  20. Engineering of a psychrophilic bacterium for the bioremediation of aromatic compounds.

    Science.gov (United States)

    Parrilli, Ermengilda; Papa, Rosanna; Tutino, Maria Luisa; Sannia, Giovanni

    2010-01-01

    Microbial degradation of aromatic hydrocarbons has been studied with the aim of developing applications for the removal of toxic compounds. Efforts have been directed toward the genetic manipulation of mesophilic bacteria to improve their ability to degrade pollutants, even though many pollution problems occur in sea waters and in effluents of industrial processes which are characterized by low temperatures. From these considerations the idea of engineering a psychrophilic microorganism for the oxidation of aromatic compounds was developed.In a previous paper it was demonstrated that the recombinant Antarctic Pseudoalteromonas haloplanktis TAC125 (PhTAC/tou) expressing a toluene-o-xylene monooxygenase (ToMO) is able to convert several aromatic compounds into corresponding catechols. In our work we improved the metabolic capability of PhTAC/tou cells by combining action of recombinant ToMO enzyme with that of the endogenous P. haloplanktis TAC125 laccase-like protein. This strategy allowed conferring new and specific degradative capabilities to a bacterium isolated from an unpolluted environment; indeed engineered PhTAC/tou cells are able to grow on aromatic compounds as sole carbon and energy sources. Our approach demonstrates the possibility to use the engineered psychrophilic bacterium for the bioremediation of chemically contaminated marine environments and/or cold effluents.

  1. Photobacterium damselae subsp. damselae, a bacterium pathogenic for marine animals and humans

    Directory of Open Access Journals (Sweden)

    Amable J. Rivas

    2013-09-01

    Full Text Available Photobacterium damselae subsp. damselae (formerly Vibrio damsela is a pathogen of a variety of marine animals including fish, crustaceans, molluscs and cetaceans. In humans, it can cause opportunistic infections that may evolve into necrotizing fasciitis with fatal outcome. Although the genetic basis of virulence in this bacterium is not completely elucidated, recent findings demonstrate that the phospholipase-D Dly (damselysin and the pore-forming toxins HlyApl and HlyAch play a main role in virulence for homeotherms and poikilotherms. The acquisition of the virulence plasmid pPHDD1 that encodes Dly and HlyApl has likely constituted a main driving force in the evolution of a highly hemolytic lineage within the subspecies. Interestingly, strains that naturally lack pPHDD1 show a strong pathogenic potential for a variety of fish species, indicating the existence of yet uncharacterized virulence factors. Future and deep analysis of the complete genome sequence of P. damselae subsp. damselae will surely provide a clearer picture of the virulence factors employed by this bacterium to cause disease in such a varied range of hosts.

  2. Photobacterium damselae subsp. damselae, a bacterium pathogenic for marine animals and humans.

    Science.gov (United States)

    Rivas, Amable J; Lemos, Manuel L; Osorio, Carlos R

    2013-01-01

    Photobacterium damselae subsp. damselae (formerly Vibrio damsela) is a pathogen of a variety of marine animals including fish, crustaceans, molluscs, and cetaceans. In humans, it can cause opportunistic infections that may evolve into necrotizing fasciitis with fatal outcome. Although the genetic basis of virulence in this bacterium is not completely elucidated, recent findings demonstrate that the phospholipase-D Dly (damselysin) and the pore-forming toxins HlyApl and HlyAch play a main role in virulence for homeotherms and poikilotherms. The acquisition of the virulence plasmid pPHDD1 that encodes Dly and HlyApl has likely constituted a main driving force in the evolution of a highly hemolytic lineage within the subspecies. Interestingly, strains that naturally lack pPHDD1 show a strong pathogenic potential for a variety of fish species, indicating the existence of yet uncharacterized virulence factors. Future and deep analysis of the complete genome sequence of Photobacterium damselae subsp. damselae will surely provide a clearer picture of the virulence factors employed by this bacterium to cause disease in such a varied range of hosts. PMID:24093021

  3. Structural characterization of the lipid A from the LPS of the haloalkaliphilic bacterium Halomonas pantelleriensis.

    Science.gov (United States)

    Carillo, Sara; Pieretti, Giuseppina; Casillo, Angela; Lindner, Buko; Romano, Ida; Nicolaus, Barbara; Parrilli, Michelangelo; Giuliano, Mariateresa; Cammarota, Marcella; Lanzetta, Rosa; Corsaro, Maria Michela

    2016-09-01

    Halomonas pantelleriensis DSM9661(Τ) is a Gram-negative haloalkaliphilic bacterium isolated from the sand of the volcanic Venus mirror lake, closed to seashore in the Pantelleria Island in the south of Italy. It is able to optimally grow in media containing 3-15 % (w/v) total salt and at pH between 9 and 10. To survive in these harsh conditions, the bacterium has developed several strategies that probably concern the bacteria outer membrane, a barrier regulating the exchange with the environment. In such a context, the lipopolysaccharides (LPSs), which are among the major constituent of the Gram-negative outer membrane, are thought to contribute to the restrictive membrane permeability properties. The structure of the lipid A family derived from the LPS of Halomonas pantelleriensis DSM 9661(T) is reported herein. The lipid A was obtained from the purified LPS by mild acid hydrolysis. The lipid A, which contains different numbers of fatty acids residues, and its partially deacylated derivatives were completely characterized by means of ESI FT-ICR mass spectrometry and chemical analysis. Preliminary immunological assays were performed, and a comparison with the lipid A structure of the phylogenetic proximal Halomonas magadiensis is also reported. PMID:27329160

  4. Isolation, cloning and characterization of an azoreductase from the halophilic bacterium Halomonas elongata.

    Science.gov (United States)

    Eslami, Maryam; Amoozegar, Mohammad Ali; Asad, Sedigheh

    2016-04-01

    Azo dyes are a major class of colorants used in various industries including textile, paper and food. These dyes are regarded as pollutant since they are not readily reduced under aerobic conditions. Halomonas elongata, a halophilic bacterium, has the ability to decolorize different mono and di-azo dyes in anoxic conditions. In this study the putative azoreductase gene of H. elongata, formerly annotated as acp, was isolated, heterologously expressed in Escherichia coli, purified and characterized. The gene product, AzoH, was found to have a molecular mass of 22 kDa. The enzyme requires NADH, as an electron donor for its activity. The apparent Km was 63 μM for NADH and 12 μM for methyl red as a mono-azo dye substrate. The specific activity for methyl red was 0.27 μmol min(-1)mg(-1). The optimum enzyme activity was achieved in 50mM sodium phosphate buffer at pH 6. Although increased salinity resulted in reduced activity, AzoH could decolorize azo dye at NaCl concentrations up to 15% (w/v). The enzyme was also shown to be able to decolorize remazol black B as a representative of di-azo dyes. This is the first report describing the sequence and activity of an azo-reducing enzyme from a halophilic bacterium. PMID:26724685

  5. INDISIM-Paracoccus, an individual-based and thermodynamic model for a denitrifying bacterium.

    Science.gov (United States)

    Araujo Granda, Pablo; Gras, Anna; Ginovart, Marta; Moulton, Vincent

    2016-08-21

    We have developed an individual-based model for denitrifying bacteria. The model, called INDISIM-Paracoccus, embeds a thermodynamic model for bacterial yield prediction inside the individual-based model INDISIM, and is designed to simulate the bacterial cell population behavior and the product dynamics within the culture. The INDISIM-Paracoccus model assumes a culture medium containing succinate as a carbon source, ammonium as a nitrogen source and various electron acceptors such as oxygen, nitrate, nitrite, nitric oxide and nitrous oxide to simulate in continuous or batch culture the different nutrient-dependent cell growth kinetics of the bacterium Paracoccus denitrificans. The individuals in the model represent microbes and the individual-based model INDISIM gives the behavior-rules that they use for their nutrient uptake and reproduction cycle. Three previously described metabolic pathways for P. denitrificans were selected and translated into balanced chemical equations using a thermodynamic model. These stoichiometric reactions are an intracellular model for the individual behavior-rules for metabolic maintenance and biomass synthesis and result in the release of different nitrogen oxides to the medium. The model was implemented using the NetLogo platform and it provides an interactive tool to investigate the different steps of denitrification carried out by a denitrifying bacterium. The simulator can be obtained from the authors on request. PMID:27179457

  6. Biogenesis of antibacterial silver nanoparticles using the endophytic bacterium Bacillus cereus isolated from Garcinia xanthochymus

    Institute of Scientific and Technical Information of China (English)

    Swetha Sunkar; C Valli Nachiyar

    2012-01-01

    Objective:To synthesize the ecofriendly nanoparticles, which is viewed as an alternative to the chemical method which initiated the use of microbes like bacteria and fungi in their synthesis. Methods: The current study uses the endophytic bacterium Bacillus cereus isolated from the Garcinia xanthochymus to synthesize the silver nanoparticles (AgNPs). The AgNPs were synthesized by reduction of silver nitrate solution by the endophytic bacterium after incubation for 3-5 d at room temperature. The synthesis was initially observed by colour change from pale white to brown which was confirmed by UV-Vis spectroscopy. The AgNPs were further characterized using FTIR, SEM-EDX and TEM analyses. Results:The synthesized nanoparticles were found to be spherical with the size in the range of 20-40 nm which showed a slight aggregation. The energy-dispersive spectra of the nanoparticle dispersion confirmed the presence of elemental silver. The AgNPs were found to have antibacterial activity against a few pathogenic bacteria like Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Salmonella typhi and Klebsiella pneumoniae. Conclusions:The endophytic bacteria identified as Bacillus cereus was able to synthesize silver nanoparticles with potential antibacterial activity.

  7. Enzymatic properties of chitinase-producing antagonistic bacterium Paenibacillus chitinolyticus with various substrates.

    Science.gov (United States)

    Song, Yong-Su; Seo, Dong-Jun; Ju, Wan-Taek; Lee, Yong-Seong; Jung, Woo-Jin

    2015-12-01

    Various chitin substrates were used to investigate the properties of enzymes produced from the chitinase-producing bacterium Paenibacillus chitinolyticus MP-306 against phytopathogens. The MP-306 bacterium was incubated in nine culture media [crab shell powder chitin (CRS), chitin-protein complex powder (CPC), carboxymethyl-chitin powder (CMC), yeast extract only (YE), LB (Trypton, NaCl, and yeast extract), GT (Trypton, NaCl, and glucose), crab shell colloidal chitin (CSC), squid pen powder chitin (SPC), and cicada slough powder chitin (CSP)] at 30 °C for 3 days. Chitinase isozymes in CPC medium were expressed strongly as CN1, CN2, CN3, CN4, CN5, and CN6 bands on native-PAGE gels. Chitinase isozymes in CPC and CMC medium were expressed as 13 bands (CS1-CS13) on SDS-PAGE gels. Chitinase isozymes were expressed strongly on SDS-PAGE gels as two bands (CS6 and CS8) on YE and LB medium and 13 bands (CS1-CS13) on SPC medium. In crude enzyme, chitinase isozymes at pH 7 and pH 9 in chitin media appeared strongly on SDS-PAGE gels. Partial purified enzyme indicated high stability of enzyme activity at various temperatures and pHs in chitin medium, while these enzymes indicated low activity staining of enzyme on electrophoresis gels at various temperatures and pHs condition of chitin medium.

  8. Extreme furfural tolerance of a soil bacterium Enterobacter cloacae GGT036.

    Science.gov (United States)

    Choi, Sun Young; Gong, Gyeongtaek; Park, Hong-Sil; Um, Youngsoon; Sim, Sang Jun; Woo, Han Min

    2015-01-10

    Detoxification process of cellular inhibitors including furfural is essential for production of bio-based chemicals from lignocellulosic biomass. Here we isolated an extreme furfural-tolerant bacterium Enterobacter cloacae GGT036 from soil sample collected in Mt. Gwanak, Republic of Korea. Among isolated bacteria, only E. cloacae GGT036 showed cell growth with 35 mM furfural under aerobic culture. Compared to the maximal half inhibitory concentration (IC50) of well-known industrial strains Escherichia coli (24.9 mM furfural) and Corynebacterium glutamicum (10 mM furfural) based on the cell density, IC50 of E. cloacae GGT036 (47.7 mM) was significantly higher after 24 h, compared to E. coli and C. glutamicum. Since bacterial cell growth was exponentially inhibited depending on linearly increased furfural concentrations in the medium, we concluded that E. cloacae GGT036 is an extreme furfural-tolerant bacterium. Recently, the complete genome sequence of E. cloacae GGT036 was announced and this could provide an insight for engineering of E. cloacae GGT036 itself or other industrially relevant bacteria.

  9. Production and characterization of bioemulsifier from a marine bacterium, Acinetobacter calcoaceticus subsp. anitratus SM7

    Directory of Open Access Journals (Sweden)

    Kulnaree Phetrong

    2008-05-01

    Full Text Available Marine bacterium strain SM7 was isolated as a bioemulsifier-producing bacterium from oil-spilled seawater in Songkhla lagoon, Thailand. It was identified as Acinetobacter calcoaceticus subsp. anitratus based on morphology, biochemicalcharacteristics and 16S rRNA sequence. A. calcoaceticus subsp. anitratus SM7 produced an extracellular emulsifying agent when grown in a minimal salt medium (pH 7.0 containing 0.3% (v/v n-heptadecane and 0.1% (w/v ammoniumhydrogen carbonate as carbon source and nitrogen source, respectively, at 30oC with agitation rate of 200 rpm. Crude bioemulsifier was recovered from the culture supernatant by ethanol precipitation with a yield of 2.94 g/l and had a criticalemulsifier concentration of 0.04 g/ml. The crude bioemulsifier was capable of emulsifying n-hexadecane in a broad pH range (6-12, temperatures (30-121oC and in the presence of NaCl up to 12% (w/v. The bioemulsifier was stable in saltsolution ranging from 0 to 0.1% (w/v of MgCl2 and CaCl2. The broad range of pH stability, thermostability and salt tolerance suggested that the bioemulsifier from A. calcoaceticus subsp. anitratus SM7 could be useful in environmentalapplication, especially bioremediation of oil-polluted seawater.

  10. The bacterium endosymbiont of Crithidia deanei undergoes coordinated division with the host cell nucleus.

    Directory of Open Access Journals (Sweden)

    Maria Cristina Machado Motta

    Full Text Available In trypanosomatids, cell division involves morphological changes and requires coordinated replication and segregation of the nucleus, kinetoplast and flagellum. In endosymbiont-containing trypanosomatids, like Crithidia deanei, this process is more complex, as each daughter cell contains only a single symbiotic bacterium, indicating that the prokaryote must replicate synchronically with the host protozoan. In this study, we used light and electron microscopy combined with three-dimensional reconstruction approaches to observe the endosymbiont shape and division during C. deanei cell cycle. We found that the bacterium replicates before the basal body and kinetoplast segregations and that the nucleus is the last organelle to divide, before cytokinesis. In addition, the endosymbiont is usually found close to the host cell nucleus, presenting different shapes during the protozoan cell cycle. Considering that the endosymbiosis in trypanosomatids is a mutualistic relationship, which resembles organelle acquisition during evolution, these findings establish an excellent model for the understanding of mechanisms related with the establishment of organelles in eukaryotic cells.

  11. Enhanced Cadmium (Cd Phytoextraction from Contaminated Soil using Cd-Resistant Bacterium

    Directory of Open Access Journals (Sweden)

    Kunchaya Setkit

    2014-01-01

    Full Text Available A cadmium (Cd-resistant bacterium, Micrococcus sp. MU1, is able to produce indole-3-acetic acid and promotes root elongation and plant growth. The potential of this bacterium on enhancement of Cd uptake and bioaccumulation of Cd in Helianthus annuus L. planted in Cd-contaminated soil was evaluated in greenhouse condition. The results showed that Micrococcus sp. MU1promoted the growth of H. annuus L. by increasing the root length, stem height, dry biomass, root to shoot ratio and also significantly increased Cd accumulation in the root and above-ground tissues of H. annuus L. compared to uninoculated control. Re-inoculation with Micrococcus sp. MU1in contaminated soil helped in promoting plant growth and Cd phytoextraction throughout the cultivation period. In addition, phytoextraction coefficient and translocation factor (TF of H. annuus L. inoculated with Micrococcus sp. MU1were higher than that of uninoculated control and TF continuously increased with time. Our results suggested that Micrococcus sp. MU1 has an ability to enhance plant growth and Cd uptake in H. annuus L. Synergistic interaction between Micrococcus sp. MU1 and H. annuus L. could be further applied for Cd phytoextraction in polluted areas.

  12. The algae-lytic ability of bacterium DC10 and the influence of environmental factors on the ability

    Institute of Scientific and Technical Information of China (English)

    SHI; Shunyu; LIU; Yongding; SHEN; Yinwu; LI; Genbao

    2005-01-01

    A lysing-bacterium DC10, isolated from Dianchi Lake of Yunnan Province, was characterized to be Pseudomonas sp. It was able to lyse some algae well, such as Microcystis viridis, Selenastrum capricornutum, and so on. In this study, it was shown that the bacterium lysed the algae by releasing a substance; the best lytic effects were achieved at Iow temperatures and in the dark. Different concentrations of CaCI2 and NaNO3 influenced the lytic effects;the ability to lyse algae decreased in the following order: pH 4 > pH 9 > pH 7 > pH 5.5. It was significant to develop a special technology with this kind of bacterium for controlling the bloomforming planktonic microalgae.

  13. Cloning of the cnr operon into a strain of Bacillaceae bacterium for the development of a suitable biosorbent.

    Science.gov (United States)

    Fosso-Kankeu, Elvis; Mulaba-Bafubiandi, Antoine F; Piater, Lizelle A; Tlou, Matsobane G

    2016-07-01

    In this study, a potential microbial biosorbent was engineered to improve its capacity to remediate heavy metal contaminated water resources. A Bacillaceae bacterium isolated from a mining area was transformed with a plasmid carrying the (pECD312)-based cnr operon that encodes nickel and cobalt resistance. The bioadsorption ability of the transformed strain was evaluated for removal of nickel from metallurgical water relative to the wildtype strain. Results showed that transformation improved the adsorption capacity of the bacterium by 37 % at nickel concentrations equivalent to 150 mg/L. Furthermore it was possible to apply prediction modelling to study the bioadsorption behaviour of the transformed strain. As such, this work may be extended to the design of a nickel bioremediation plant utilising the newly developed Bacillaceae bacterium as a biosorbent. PMID:27263009

  14. Bacterium-like Particles for efficient immune stimulation of existing vaccines and new subunit vaccines in mucosal applications

    Directory of Open Access Journals (Sweden)

    Natalija eVan Braeckel-Budimir

    2013-09-01

    Full Text Available The successful development of a mucosal vaccine critically depends on the use of a safe and effective immunostimulant and/or carrier system. This review describes the effectiveness and mode of action of an immunostimulating particle derived from bacteria in mucosal subunit vaccines. The non-living particles, designated Bacterium-like Particles (BLPs are based on the food-grade bacterium Lactococcus lactis. The focus of the overview is on the development of intranasal BLP-based vaccines to prevent diseases caused by influenza and respiratory syncytial virus, and includes a selection of Phase I clinical data for the intranasal FluGEM vaccine.

  15. Draft Genome Sequence of the Endophytic Bacterium Enterobacter spp. MR1, Isolated from Drought Tolerant Plant (Butea monosperma)

    OpenAIRE

    Parakhia, Manoj V.; Tomar, Rukam S.; Malaviya, Bipin J.; Dhingani, Rashmin M.; Rathod, Visha M.; Thakkar, Jalpa R.; Golakiya, B. A.

    2013-01-01

    Enterobacter sp. MR1 an endophytic plant growth promoting bacterium was isolated from the roots of Butea monosperma, a drought tolerant plant. Genome sequencing of Enterobacter spp. MR1 was carried out in Ion Torrent (PGM), Next Generation Sequencer. The data obtained revealed 640 contigs with genome size of 4.58 Mb and G+C content of 52.8 %. This bacterium may contain genes responsible for inducing drought tolerance in plant, including genes for phosphate solubilization, growth hormones and ...

  16. Bacterium-Like Particles for Efficient Immune Stimulation of Existing Vaccines and New Subunit Vaccines in Mucosal Applications

    Science.gov (United States)

    Van Braeckel-Budimir, Natalija; Haijema, Bert Jan; Leenhouts, Kees

    2013-01-01

    The successful development of a mucosal vaccine depends critically on the use of a safe and effective immunostimulant and/or carrier system. This review describes the effectiveness and mode of action of an immunostimulating particle, derived from bacteria, used in mucosal subunit vaccines. The non-living particles, designated bacterium-like particles are based on the food-grade bacterium Lactococcus lactis. The focus of the overview is on the development of intranasal BLP-based vaccines to prevent diseases caused by influenza and respiratory syncytial virus, and includes a selection of Phase I clinical data for the intranasal FluGEM vaccine. PMID:24062748

  17. Effect of antagonistic bacteria and soil disinfectant on soil bacterium community in banana fusarium wilt disease area%施用拮抗菌饼肥发酵液和土壤消毒剂对香蕉枯萎病病区土壤细菌群落的影响

    Institute of Scientific and Technical Information of China (English)

    周登博; 井涛; 谭昕; 陈波; 张锡炎; 高祝芬

    2013-01-01

    [Objective] The objective of the present study is to elucidate the effects of the application of cake fertilizer fermentation fluid with antagonistic bacteria and soil disinfectant chlorine dioxide on the occurrence of banana fusarium wilt disease and soil bacterium community.[Method] Under the field cultivation conditions,the Biolog and T-RFLP method was used to investigate the soil bacterium diversity and community features in different treatments at different periods.[Result] The results show that both cake fertilizer fermentation fluid with antagonistic bacteria and soil disinfectant could reduce disease index of banana fusarium wilt disease significantly,the highest control effect could reach 60.82% with the combined application of these two methods.The result of Biolog eco plate shows that the application of cake fertilizer fermentation fluid with antagonistic bacteria could improve soil microbial AWCD (average well color development) and population uniformity,the use of soil disinfectant significantly reduced the soil microbial population' s abundance and the uniformity.Principal component analysis shows that the soil microbial population using carbon source had an increasing trend throughout the banana growing season,the main carbon sources in the early stage were amino acids,carboxylic acids,amphiphilic compounds and carbohydrates,and the increased main carbon sources in the later stage were carboxylic acids and amphiphilic compounds.Soil bacterial diversity analysis by T-RFLP shows that the treatments of cake fertilizer fermentation fluid with antagonistic bacteria had the highest bacterial TRFs (Terminal restriction fragment)fragments,which resulted from the increase of Flavobacterium,Pseudomona and Lactobacillus population in the soil.[Conclusion]The application of cake fertilizer fermentation fluid with antagonistic bacteria combining soil disinfectant could increase antagonistic microorganisms species,enhance soil microbial diversity,improve soil

  18. Biochemical Characterization and Relative Expression Levels of Multiple Carbohydrate Esterases of the Xylanolytic Rumen Bacterium Prevotella ruminicola 23 Grown on an Ester-Enriched Substrate

    NARCIS (Netherlands)

    Kabel, M.A.; Yeoman, C.J.; Han, Y.; Dodd, D.; Abbas, C.A.; Bont, de J.A.M.; Morrison, M.; Cann, I.K.O.; Mackie, R.I.

    2011-01-01

    We measured expression and used biochemical characterization of multiple carbohydrate esterases by the xylanolytic rumen bacterium Prevotella ruminicola 23 grown on an ester-enriched substrate to gain insight into the carbohydrate esterase activities of this hemicellulolytic rumen bacterium. The P.

  19. Dehalobacter restrictus gen. nov. and sp. nov., a strictly anaerobic bacterium that reductively dechlorinates tetra- and trichloroethene in an anaerobic respiration

    NARCIS (Netherlands)

    Holliger, C; Hahn, D; Harmsen, H; Ludwig, W; Schumacher, W; Tindall, B; Vazquez, F; Weiss, N; Zehnder, AJB

    1998-01-01

    The highly enriched anaerobic bacterium that couples the reductive dechlorination of tetrachloroethene to growth, previously referred to as PER-K23, was obtained in pure culture and characterized. The bacterium, which does not form spores, is a small, gram-negative rod with one lateral flagellum. It

  20. High Prevalence of Antibodies against the Bacterium Treponema pallidum in Senegalese Guinea Baboons (Papio papio.

    Directory of Open Access Journals (Sweden)

    Sascha Knauf

    Full Text Available The bacterium Treponema pallidum is known to cause syphilis (ssp. pallidum, yaws (ssp. pertenue, and endemic syphilis (ssp. endemicum in humans. Nonhuman primates have also been reported to be infected with the bacterium with equally versatile clinical manifestations, from severe skin ulcerations to asymptomatic. At present all simian strains are closely related to human yaws-causing strains, an important consideration for yaws eradication. We tested clinically healthy Guinea baboons (Papio papio at Parc National Niokolo Koba in south eastern Senegal for the presence of anti-T. pallidum antibodies. Since T. pallidum infection in this species was identified 50 years ago, and there has been no attempt to treat non-human primates for infection, it was hypothesized that a large number of West African baboons are still infected with simian strains of the yaws-bacterium. All animals were without clinical signs of treponematoses, but 18 of 20 (90% baboons tested positive for antibodies against T. pallidum based on treponemal tests. Yet, Guinea baboons seem to develop no clinical symptoms, though it must be assumed that infection is chronic or comparable to the latent stage in human yaws infection. The non-active character is supported by the low anti-T. pallidum serum titers in Guinea baboons (median = 1:2,560 versus serum titers that are found in genital-ulcerated olive baboons with active infection in Tanzania (range of medians among the groups of initial, moderate, and severe infected animals = 1:15,360 to 1:2.097e+7. Our findings provide evidence for simian infection with T. pallidum in wild Senegalese baboons. Potentially, Guinea baboons in West Africa serve as a natural reservoir for human infection, as the West African simian strain has been shown to cause sustainable yaws infection when inoculated into humans. The present study pinpoints an area where further research is needed to support the currently on-going second WHO led yaws eradication

  1. Metabolism of 4-chloro-2-nitrophenol in a Gram-positive bacterium, Exiguobacterium sp. PMA

    Directory of Open Access Journals (Sweden)

    Arora Pankaj

    2012-11-01

    Full Text Available Abstract Background Chloronitrophenols (CNPs are widely used in the synthesis of dyes, drugs and pesticides, and constitute a major group of environmental pollutants. 4-Chloro-2-nitrophenol (4C2NP is an isomer of CNPs that has been detected in various industrial effluents. A number of physicochemical methods have been used for treatment of wastewater containing 4C2NP. These methods are not as effective as microbial degradation, however. Results A 4C2NP-degrading bacterium, Exiguobacterium sp. PMA, which uses 4C2NP as the sole carbon and energy source was isolated from a chemically-contaminated site in India. Exiguobacterium sp. PMA degraded 4C2NP with the release of stoichiometeric amounts of chloride and ammonium ions. The effects of different substrate concentrations and various inoculum sizes on degradation of 4C2NP were investigated. Exiguobacterium sp. PMA degraded 4C2NP up to a concentration of 0.6 mM. High performance liquid chromatography and gas chromatography–mass spectrometry identified 4-chloro-2-aminophenol (4C2AP and 2-aminophenol (2AP as possible metabolites of the 4C2NP degradation pathway. The crude extract of 4C2NP-induced PMA cells contained enzymatic activity for 4C2NP reductase and 4C2AP dehalogenase, suggesting the involvement of these enzymes in the degradation of 4C2NP. Microcosm studies using sterile and non-sterile soils spiked with 4C2NP were carried out to monitor the bioremediation potential of Exiguobacterium sp. PMA. The bioremediation of 4C2NP by Exiguobacterium sp. PMA was faster in non-sterilized soil than sterilized soil. Conclusions Our studies indicate that Exiguobacterium sp. PMA may be useful for the bioremediation of 4C2NP-contaminated sites. This is the first report of (i the formation of 2AP in the 4C2NP degradation pathway by any bacterium and (iii the bioremediation of 4C2NP by any bacterium.

  2. Genetic manipulation of carotenoid biosynthesis in the green sulfur bacterium Chlorobium tepidum

    DEFF Research Database (Denmark)

    Frigaard, Niels-Ulrik; Maresca, Julia A; Yunker, Colleen E;

    2004-01-01

    The green sulfur bacterium Chlorobium tepidum is a strict anaerobe and an obligate photoautotroph. On the basis of sequence similarity with known enzymes or sequence motifs, nine open reading frames encoding putative enzymes of carotenoid biosynthesis were identified in the genome sequence of C....... tepidum, and all nine genes were inactivated. Analysis of the carotenoid composition in the resulting mutants allowed the genes encoding the following six enzymes to be identified: phytoene synthase (crtB/CT1386), phytoene desaturase (crtP/CT0807), zeta-carotene desaturase (crtQ/CT1414), gamma......-carotene desaturase (crtU/CT0323), carotenoid 1',2'-hydratase (crtC/CT0301), and carotenoid cis-trans isomerase (crtH/CT0649). Three mutants (CT0180, CT1357, and CT1416 mutants) did not exhibit a discernible phenotype. The carotenoid biosynthetic pathway in C. tepidum is similar to that in cyanobacteria and plants...

  3. Isolation of pigmentation mutants of the green filamentous photosynthetic bacterium Chloroflexus aurantiacus

    International Nuclear Information System (INIS)

    Mutants deficient in the production of bateriochlorophyll c (Bchl c) and one mutant lacking colored carotenoids were isolated from the filamentous gliding bacterium Chloroflexus aurantiacus, Mutagenesis was achieved by using UV radiation or N-methyl-N'-nitro-N-nitrosoguanidine. Several clones were isolated that were deficient in Bchl c synthesis. All reverted. One double mutant deficient both in Bchl c synthesis and in the synthesis of colored carotenoids under anaerobic conditions was isolated. Isolation of a revertant in Bchl c synthesis from this double mutant produced a mutant strain of Chloroflexus that grew photosynthetically under anaerobic conditions and lacked colored carotenoids. Analysis of pigment contents and growth rates of the mutants revealed a positive association between growth rate and content of Bchl c under light-limiting conditions. 11 references, 4 figures, 3 tables

  4. Draft whole genome sequence of the cyanide-degrading bacterium Pseudomonas pseudoalcaligenes CECT5344.

    Science.gov (United States)

    Luque-Almagro, Víctor M; Acera, Felipe; Igeño, Ma Isabel; Wibberg, Daniel; Roldán, Ma Dolores; Sáez, Lara P; Hennig, Magdalena; Quesada, Alberto; Huertas, Ma José; Blom, Jochen; Merchán, Faustino; Escribano, Ma Paz; Jaenicke, Sebastian; Estepa, Jessica; Guijo, Ma Isabel; Martínez-Luque, Manuel; Macías, Daniel; Szczepanowski, Rafael; Becerra, Gracia; Ramirez, Silvia; Carmona, Ma Isabel; Gutiérrez, Oscar; Manso, Isabel; Pühler, Alfred; Castillo, Francisco; Moreno-Vivián, Conrado; Schlüter, Andreas; Blasco, Rafael

    2013-01-01

    Pseudomonas pseudoalcaligenes CECT5344 is a Gram-negative bacterium able to tolerate cyanide and to use it as the sole nitrogen source. We report here the first draft of the whole genome sequence of a P. pseudoalcaligenes strain that assimilates cyanide. Three aspects are specially emphasized in this manuscript. First, some generalities of the genome are shown and discussed in the context of other Pseudomonadaceae genomes, including genome size, G + C content, core genome and singletons among other features. Second, the genome is analysed in the context of cyanide metabolism, describing genes probably involved in cyanide assimilation, like those encoding nitrilases, and genes related to cyanide resistance, like the cio genes encoding the cyanide insensitive oxidases. Finally, the presence of genes probably involved in other processes with a great biotechnological potential like production of bioplastics and biodegradation of pollutants also is discussed. PMID:22998548

  5. Identification of a denitrifying bacterium and verification of its anaerobic ammonium oxidation ability

    Institute of Scientific and Technical Information of China (English)

    HU; Baolan; ZHENG; Ping; LI; Jinye; XU; Xiangyang; JIN; Rencun

    2006-01-01

    A strain D3 of denitrifying bacterium was isolated from an anammox reactor, and identified as Pseudomonas mendocina based on the morphological and physiological assay, Vitek test,Biolog test, (G+C) mol% content, and 16S rDNA phylogenetic analysis. As a typical denitrifying bactration of 88.5 mg N/L. The optimal pH and growth temperature were 7.84 and 34.9℃, respectively.Strain D3 was able to oxidize ammonia under anaerobic condition. The maximum nitrate and ammoof ammonia to nitrate was 1:1.91. Electron microscopic observation revealed peculiar cell inclusions in strain D3. Because of its relation to anammox activity, strain D3 was presumed to be anammoxosome.The present investigation proved that denitrifying bacteria have the anammox ability, and the results have engorged the range of anammox populations.

  6. A Mutant Strain of a Surfactant-Producing Bacterium with Increased Emulsification Activity

    Institute of Scientific and Technical Information of China (English)

    Liu Qingmei; Yao Jianming; Pan Renrui; Yu Zengliang

    2005-01-01

    As reported in this paper, a strain of oil-degrading bacterium Sp- 5- 3 was determined to belong to Enterobacteriaceae, which would be useful for microbial enhanced oil recovery(MEOR). The aim of our study was to generate a mutant using low energy N+ beam implantation. With 10 keV of energy and 5.2 × 10TM N+/cm2 of dose - the optimum condition, a mutant,S - 34, was obtained, which had nearly a 5-fold higher surface and a 13-fold higher of emulsification activity than the wild type. The surface activity was measured by two methods, namely, a surface tension measuring instrument and a recording of the repulsive circle of the oil film; the emulsification activity was scaled through measuring the separating time of the oil-fermentation mixture. The metabolic acid was determined as methane by means of gas chromatography.

  7. Heterotrophic ammonium removal characteristics of an aerobic heterotrophic nitrifying-denitrifying bacterium, Providencia rettgeri YL

    Institute of Scientific and Technical Information of China (English)

    TAYLOR Shauna M; HE Yiliang; ZHAO Bin; HUANG Jue

    2009-01-01

    Bacterium Providencia rettgeri YL was found to exhibit an unusual ability to heterotrophically nitrify and aerobically denitrify various concentrations of ammonium (NH4+-N). In order to further analyze its removal ability, several experiments were conducted to identify the growth and ammonium removal response in different carbon to nitrogen (C/N) mass ratios, shaking speeds, temperatures, ammonium concentrations and to qualitatively verify the production of nitrogen gas using gas chromatography techniques. Results showed that under optimum conditions (C/N 10, 30℃, 120 r/min), YL can significantly remove low and high concentrations of ammonium within 12 to 48 h of growth. The nitrification products hydroxylamine (NH2OH), nitrite (NO2-) and nitrate (NO3-) as well as the denitrification product, nitrogen gas (N2), were detected under completely aerobic conditions.

  8. Structure of ribose 5-phosphate isomerase from the probiotic bacterium Lactobacillus salivarius UCC118

    International Nuclear Information System (INIS)

    The crystal structure of ribose 5-phosphate isomerase has been determined to 1.72 Å resolution and is presented with a brief comparison to other known ribose 5-phosphate isomerase A structures. The structure of ribose 5-phosphate isomerase from the probiotic bacterium Lactobacillus salivarius UCC188 has been determined at 1.72 Å resolution. The structure was solved by molecular replacement, which identified the functional homodimer in the asymmetric unit. Despite only showing 57% sequence identity to its closest homologue, the structure adopted the typical α and β d-ribose 5-phosphate isomerase fold. Comparison to other related structures revealed high homology in the active site, allowing a model of the substrate-bound protein to be proposed. The determination of the structure was expedited by the use of in situ crystallization-plate screening on beamline I04-1 at Diamond Light Source to identify well diffracting protein crystals prior to routine cryocrystallography

  9. A Mutant Strain of a Surfactant-Producing Bacterium with Increased Emulsification Activity

    Science.gov (United States)

    Liu, Qingmei; Yao, Jianming; Pan, Renrui; Yu, Zengliang

    2005-06-01

    As reported in this paper, a strain of oil-degrading bacterium Sp-5-3 was determined to belong to Enterobacteriaceae, which would be useful for microbial enhanced oil recovery (MEOR). The aim of our study was to generate a mutant using low energy N+ beam implantation. With 10 keV of energy and 5.2 × 1014 N+/cm2 of dose - the optimum condition, a mutant, S-34, was obtained, which had nearly a 5-fold higher surface and a 13-fold higher of emulsification activity than the wild type. The surface activity was measured by two methods, namely, a surface tension measuring instrument and a recording of the repulsive circle of the oil film; the emulsification activity was scaled through measuring the separating time of the oil-fermentation mixture. The metabolic acid was determined as methane by means of gas chromatography.

  10. Brevibacterium rufescens nov. comb. , a facultative anaerobic methylotrophic bacterium from oil-bearing strata

    Energy Technology Data Exchange (ETDEWEB)

    Nazina, T.N.

    1981-03-01

    The paper presents the results of studying the bacterial population from the microaerophilic zone of oil-bearing strata of the Apsheron Peninsula. The incidence of bacteria capable of growing at the account of organic substances present in stratal water could reach dozens of thousands of cells in 1 ml. A bacterium predominant in the bacterial cenosis of the microaerophilic zone was islated as a pure culture. A new combination, Brevibacterium rufescens nov. comb. was created on the basis of morphological, physiologo-biochemical properties and the GC content in the DNA of the organism under study. The microorganism is adapted to its habitat in a number of properties. The necessity of recreating the genus Brevibacterium is discussed.

  11. Genome sequence of the marine bacterium Corynebacterium maris type strain Coryn-1(T) (= DSM 45190(T)).

    Science.gov (United States)

    Schaffert, Lena; Albersmeier, Andreas; Bednarz, Hanna; Niehaus, Karsten; Kalinowski, Jörn; Rückert, Christian

    2013-07-30

    Corynebacterium maris Coryn-1(T) Ben-Dov et al. 2009 is a member of the genus Corynebacterium which contains Gram-positive, non-spore forming bacteria with a high G+C content. C. maris was isolated from the mucus of the Scleractinian coral Fungia granulosa and belongs to the aerobic and non-haemolytic corynebacteria. It displays tolerance to salts (up to 10%) and is related to the soil bacterium Corynebacterium halotolerans. As this is a type strain in a subgroup of Corynebacterium without complete genome sequences, this project, describing the 2.78 Mbp long chromosome and the 45.97 kbp plasmid pCmaris1, with their 2,584 protein-coding and 67 RNA genes, will aid the G enomic E ncyclopedia of Bacteria and Archaea project. PMID:24501635

  12. Triplet excited state spectra and dynamics of carotenoids from the thermophilic purple photosynthetic bacterium Thermochromatium tepidum

    Energy Technology Data Exchange (ETDEWEB)

    Niedzwiedzki, Dariusz; Kobayashi, Masayuki; Blankenship, R. E.

    2011-01-13

    Light-harvesting complex 2 from the anoxygenic phototrophic purple bacterium Thermochromatium tepidum was purified and studied by steady-state absorption, fluorescence and flash photolysis spectroscopy. Steady-state absorption and fluorescence measurements show that carotenoids play a negligible role as supportive energy donors and transfer excitation to bacteriochlorophyll-a with low energy transfer efficiency of ~30%. HPLC analysis determined that the dominant carotenoids in the complex are rhodopin and spirilloxanthin. Carotenoid excited triplet state formation upon direct (carotenoid) or indirect (bacteriochlorophyll-a Q{sub x} band) excitation shows that carotenoid triplets are mostly localized on spirilloxanthin. In addition, no triplet excitation transfer between carotenoids was observed. Such specific carotenoid composition and spectroscopic results strongly suggest that this organism optimized carotenoid composition in the light-harvesting complex 2 in order to maximize photoprotective capabilities of carotenoids but subsequently drastically suppressed their supporting role in light-harvesting process.

  13. The Antitumor Components from Marine-derived Bacterium Streptoverticillium luteoverticillatum 11014 Ⅱ

    Institute of Scientific and Technical Information of China (English)

    LI Dehai; ZHU Tianjiao; FANG Yuchun; LIU Hongbing; GU Qianqun; ZHU Weiming

    2007-01-01

    Eight known compounds were isolated from a marine-derived bacterium Streptoverticillium luteoverticillatum 11014 using bioassay-guided fractionations. Their structures were identified by spectral analysis as bis (4-hydroxybenzyl) ether (1), p-hydroxyphenylethyl alcohol (2), N-(4-hydroxyphenethyl) acetamide (3), indole-3 carboxylic acid methyl ester (4), dibenzo[b,e] [1,4]dioxine (5), thymine (6), cytosine deoxyribonucleoside (7) and 2, 3-butanediol (8). These compounds were evaluated for their cytotoxic activities against K562 cell line with the SRB method for the first time. Compounds 2 and 4 showed cytotoxcities with IC50 values of 101.1 and 165.3 μmolL-1, respectively. All compounds were isolated from S. luteoverticillatum 11014 for the first time.

  14. Chemical compounds effective against the citrus Huanglongbing bacterium 'Candidatus Liberibacter asiaticus' in planta.

    Science.gov (United States)

    Zhang, Muqing; Powell, Charles A; Zhou, Lijuan; He, Zhenli; Stover, Ed; Duan, Yongping

    2011-09-01

    Citrus Huanglongbing (HLB) is one of the most destructive diseases of citrus worldwide and is threatening the survival of the Floridian citrus industry. Currently, there is no established cure for this century-old and emerging disease. As a possible control strategy for citrus HLB, therapeutic compounds were screened using a propagation test system with 'Candidatus Liberibacter asiaticus'-infected periwinkle and citrus plants. The results demonstrated that the combination of penicillin and streptomycin (PS) was effective in eliminating or suppressing the 'Ca. L. asiaticus' bacterium and provided a therapeutically effective level of control for a much longer period of time than when administering either antibiotic separately. When treated with the PS, 'Ca. L. asiaticus'-infected periwinkle cuttings achieved 70% of regeneration rates versus citrus plants. This may provide a useful tool for the management of citrus HLB and other Liberibacter-associated diseases.

  15. Capnocytophaga ochracea-related Bacterium Bacteremia in a Hypertrophic Cardiomyopathy Patient without Neutropenia.

    Science.gov (United States)

    Ito, Shimpei; Hagiya, Hideharu; Kimura, Keigo; Nishi, Isao; Yoshida, Hisao; Kioka, Hidetaka; Ohtani, Tomohito; Yamaguchi, Osamu; Tanabe, Kazuaki; Tomono, Kazunori; Sakata, Yasushi

    2016-01-01

    Gram-negative fusiform rods were detected in a blood culture obtained from a 63-year-old man who had been hospitalized for a long duration for severe heart failure. Although the organism could not be identified using a conventional method, it was finally identified as a bacterium of the Capnocytophaga ochracea group based on the results of biochemical testing, 16S rRNA sequencing and a matrix-assisted laser desorption ionization time-of-flight mass spectrometry analysis. Although neutropenic patients with poor oral hygiene are exclusively vulnerable to Capnocytophaga bacteremia, this case was unique because such predisposing conditions were not noted. A multi-centered investigation is warranted for a better understanding of this clinically rare, but potentially pathogenic organism. PMID:27629977

  16. Plague bacterium as a transformer species in prairie dogs and the grasslands of western North America.

    Science.gov (United States)

    Eads, David A; Biggins, Dean E

    2015-08-01

    Invasive transformer species change the character, condition, form, or nature of ecosystems and deserve considerable attention from conservation scientists. We applied the transformer species concept to the plague bacterium Yersinia pestis in western North America, where the pathogen was introduced around 1900. Y. pestis transforms grassland ecosystems by severely depleting the abundance of prairie dogs (Cynomys spp.) and thereby causing declines in native species abundance and diversity, including threatened and endangered species; altering food web connections; altering the import and export of nutrients; causing a loss of ecosystem resilience to encroaching invasive plants; and modifying prairie dog burrows. Y. pestis poses an important challenge to conservation biologists because it causes trophic-level perturbations that affect the stability of ecosystems. Unfortunately, understanding of the effects of Y. pestis on ecosystems is rudimentary, highlighting an acute need for continued research. PMID:25817984

  17. Phylogeny of the filamentous bacterium 'Nostocoida limicola' III from activated sludge.

    Science.gov (United States)

    Liu, J R; McKenzie, C A; Seviour, E M; Webb, R I; Blackall, L L; Saint, C P; Seviour, R J

    2001-01-01

    Five strains of the filamentous bacterium 'Nostocoida limicola' III were successfully isolated into pure culture from samples of activated sludge biomass from five plants in Australia. 16S rRNA gene sequence analyses showed that all isolates were members of the Planctomycetales, most closely related to Isosphaera pallida, but they differed phenotypically from this species in that they did not glide and were not thermotolerant. The ultrastructure of these 'N. limicola' III isolates was also consistent with them being Planctomycetales, in that they possessed complex intracellular membrane systems compartmentalizing the cells. However, the arrangements of these intracellular membranes differed between isolates. These data confirm that 'N. limicola' III is phylogenetically unrelated to both 'N. limicola' I and 'N. limicola' II, activated sludge filamentous bacteria which share morphological features in common with 'N. limicola' III and which have been presumed historically to be the same or very similar bacteria. PMID:11211260

  18. The structure of ferricytochrome c552 from the psychrophilic marine bacterium Colwellia psychrerythraea 34H

    Science.gov (United States)

    Harvilla, Paul B.; Wolcott, Holly N.

    2014-01-01

    Approximately 40% of all proteins are metalloproteins, and approximately 80% of Earth’s ecosystems are at temperatures ≤ 5 °C, including 90% of the global ocean. Thus, an essential aspect of marine metallobiochemistry is an understanding of the structure, dynamics, and mechanisms of cold adaptation of metalloproteins from marine microorganisms. Here, the molecular structure of the electron-transfer protein cytochrome c552 from the psychrophilic marine bacterium Colwellia psychrerythraea 34H has been determined by X-ray crystallography (PDB: 4O1W). The structure is highly superimposable with that of the homologous cytochrome from the mesophile Marinobacter hydrocarbonoclasticus. Based on structural analysis and comparison of psychrophilic, psychrotolerant, and mesophilic sequences, a methionine-based ligand-substitution mechanism for psychrophilic protein stabilization is proposed. PMID:24727932

  19. [Expression of phosphofructokinase gene from Escherichia coli K-12 in obligately autotrophic bacterium Acidithiobacillus thiooxidans].

    Science.gov (United States)

    Tian, Keli; Lin, Jianqun; Liu, Xiangmei; Liu, Ying; Zhang, Changkai

    2003-10-01

    A plasmid pSDK-1 containing the Escherichia coli phosphofructokinase-1 (EC 2.7.1. 11) gene (pfkA) was constructed and transferred into Acidithiobacillus thiooxidans Tt-Z2 by conjugation. The transfer frequency of plasmid from E. coli to Tt-Z2 was 2.6 x 10(-6). More than 68% of Tt-Z2 cells carried the recombinant plasmids after being cultured for 50 generations without selective pressure, which showed that pSDK-1 was maintained consistently in Tt-Z2. The pfkA gene from E. coli could be expressed in this obligately autotrophic bacterium but the enzyme activity (14 U/g was lower than that in E. coli (K-12: 86 U/g; DF1010 carrying plasmid pSDK-1: 97 U/g). In th presence of glucose, the Tt-Z2 transconjugant consumed glucose leading to a better growth yield.

  20. DNA Microarray Analysis of Gene Expression in Antifungal Bacterium of Bacillus lenthmorbus WJ5

    International Nuclear Information System (INIS)

    This simultaneous expression levels of antifungal activity related was analyzed by DNA microarray. We constructured DNA chips contained 2,000 randomly digested genome spots of the antifungal bacterium of Bacillus lentimorbus WJ5 and compared it squantitative aspect with 7 antifungal activity deficient mutants induced by gamma radiation . From the analysis of microarray hybridization by the Gene Cluster, totally 408 genes were expressed and 20 genes among them were significantly suppressed in mutants. pbuX, ywbA, ptsG,yufO, and ftsY were simultaneously down-regulated in all muatants. It suggested that they were supposed to be related to the antifungal activity of B. lentimorbus WJ5

  1. A Marine Sulfate-Reducing Bacterium Producing Multiple Antibiotics: Biological and Chemical Investigation

    Directory of Open Access Journals (Sweden)

    Xiaoliang Wang

    2009-07-01

    Full Text Available A marine sulfate-reducing bacterium SRB-22 was isolated by means of the agar shake dilution method and identified as Desulfovibrio desulfuricans by morphological, physiological and biochemical characteristics and 16S rDNA analysis. In the bioassay, its extract showed broad-spectrum antimicrobial activity using the paper disc agar diffusion method. This isolate showed a different antimicrobial profile than either ampicillin or nystatin and was found to produce at least eight antimicrobial components by bioautography. Suitable fermentation conditions for production of the active constituents were determined to be 28 day cultivation at 25 °C to 30 °C with a 10% inoculation ratio. Under these conditions, the SRB-22 was fermented, extracted and chemically investigated. So far an antimicrobial compound, mono-n-butyl phthalate, and an inactive compound, thymine, have been isolated and characterized.

  2. Molecular Mechanisms of Adaptation of the Moderately Halophilic Bacterium Halobacillis halophilus to Its Environment

    Science.gov (United States)

    Hänelt, Inga; Müller, Volker

    2013-01-01

    The capability of osmoadaptation is a prerequisite of organisms that live in an environment with changing salinities. Halobacillus halophilus is a moderately halophilic bacterium that grows between 0.4 and 3 M NaCl by accumulating both chloride and compatible solutes as osmolytes. Chloride is absolutely essential for growth and, moreover, was shown to modulate gene expression and activity of enzymes involved in osmoadaptation. The synthesis of different compatible solutes is strictly salinity- and growth phase-dependent. This unique hybrid strategy of H. halophilus will be reviewed here taking into account the recently published genome sequence. Based on identified genes we will speculate about possible scenarios of the synthesis of compatible solutes and the uptake of potassium ion which would complete our knowledge of the fine-tuned osmoregulation and intracellular osmolyte balance in H. halophilus. PMID:25371341

  3. The glucose transport system of the hyperthermophilic anaerobic bacterium Thermotoga neapolitana

    Energy Technology Data Exchange (ETDEWEB)

    Galperin, M.Y.; Noll, K.M.; Romano, A.H. [Univ. of Connecticut, Storrs, CT (United States)

    1996-08-01

    The glucose transport system of the extremely thermophilic anaerobic bacterium Thermotoga neapolitana was studied with the nonmetabolizable glucose analog 2-deoxy-D-glucose (2-DOG). T. neapolitana accumulated 2-DOG against a concentration gradient in an intracellular free sugar pool that was exchangeable with external D-glucose. This active transport of 2-DOG was dependent upon the presence of sodium ion and an external source of energy, such as pyruvate, and was inhibited by arsenate and gramicidin D. There was no phosphoenolpyruvate-dependent phosphorylation of glucose, 2-DOG, or fructose by cell extracts or toluene-treated cells, indicating the absence of a phosphoenolpyruvate:sugar phosphotransferase system. These data indicate that D-glucose is taken up by T.neapolitana via an active transport system that is energized by an ion gradient generated by ATP, derived from substrate-level phosphorylation. 33 refs., 3 figs., 1 tab.

  4. Microbially influenced corrosion of stainless steel by marine bacterium Vibrio natriegens: (I) Corrosion behavior

    Energy Technology Data Exchange (ETDEWEB)

    Cheng Sha; Tian Jintao [Institute of Materials Science and Engineering, Ocean University of China, Qingdao 266100 (China); Chen Shougang, E-mail: sgchen@ouc.edu.cn [Institute of Materials Science and Engineering, Ocean University of China, Qingdao 266100 (China); Lei Yanhua; Chang Xueting; Liu Tao [Institute of Materials Science and Engineering, Ocean University of China, Qingdao 266100 (China); Yin Yansheng, E-mail: yys2006@ouc.edu.cn [Institute of Materials Science and Engineering, Ocean University of China, Qingdao 266100 (China)

    2009-04-30

    The microbially influenced corrosion of stainless steel (SS) by marine bacterium Vibrio natriegens (V. natriegens) was investigated using surface analysis (atomic force microscopy (AFM), scanning electron microscopy (SEM), and energy dispersive X-ray analysis (EDXA)) and electrochemical techniques (the open circuit potential, electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization curves ). AFM images corroborated the results from the EIS models which show biofilm attachment and subsequent detachment over time. The SEM images revealed the occurrence of micro-pitting corrosion underneath the biofilms on the metal surface after the biofilm removal. The presence of carbon, oxygen, phosphor and sulfur obtained from EDXA proved the formation of biofilm. The electrochemical results showed that the corrosion of SS was accelerated in the presence of V. natriegens based on the decrease in the resistance of the charge transfer resistance (R{sub ct}) obtained from EIS and the increase in corrosion current densities obtained from potentiodynamic polarization curves.

  5. Microbially influenced corrosion of 303 stainless steel by marine bacterium Vibrio natriegens: (II) Corrosion mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Yin Yansheng, E-mail: yys2006@ouc.edu.cn [Institute of Ocean Materials and Engineering, Shanghai Maritime University, Shanghai 200135 (China); Cheng Sha [Institute of Materials Science and Engineering, Ocean University of China, Qingdao 266100 (China); Chen Shougang, E-mail: sgchen@ouc.edu.cn [Institute of Materials Science and Engineering, Ocean University of China, Qingdao 266100 (China); Tian Jintao; Liu Tao; Chang Xueting [Institute of Materials Science and Engineering, Ocean University of China, Qingdao 266100 (China)

    2009-04-30

    Electrochemical techniques (electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization curves) and surface analysis (scanning electron microscopy (SEM)) were carried out to determine the possible mechanism of the microbially influenced corrosion of 303 stainless steel (303 SS) by marine bacterium Vibrio natriegens (V. natriegens). In order to clarify the mechanism, 303 SS coupons were immersed in four different mediums. EIS results were interpreted with different equivalent circuits to model the physicoelectric characteristics of the electrode/biofilm/solution interface. The results showed that N{sub 2}-fixation actually promoted the corrosion of 303 SS; however, the influence of the produced NH{sub 3} was negligible. It can be speculated that the electron transfer and/or the nitrogenase catalyzing the process may influence the corrosion.

  6. Uncoupling effect of fatty acids in halo- and alkalotolerant bacterium Bacillus pseudofirmus FTU.

    Science.gov (United States)

    Popova, I V; Bodrova, M E; Mokhova, E N; Muntyan, M S

    2004-10-01

    Natural uncouplers of oxidative phosphorylation, long-chain non-esterified fatty acids, cause uncoupling in the alkalo- and halotolerant bacterium Bacillus pseudofirmus FTU. The uncoupling effect in the bacterial cells was manifested as decrease of membrane potential and increase of respiratory activity. The membrane potential decrease was detected only in bacterial cells exhausted by their endogenous substrates. In proteoliposomes containing reconstituted bacterial cytochrome c oxidase, fatty acids caused a "mild" uncoupling effect by reducing membrane potential only at low rate of membrane potential generation. "Free respiration" induced by the "mild" uncouplers, the fatty acids, can be considered as possible mechanism responsible for adaptation of the bacteria to a constantly changed environment. PMID:15527418

  7. Vibrio ruber (S2A1, a Marine Bacterium that Exhibits Significant Antimicrobial Activity

    Directory of Open Access Journals (Sweden)

    Wan Norhana, N.

    2005-01-01

    Full Text Available A potential antimicrobial-producing marine bacterium, designated as S2A1, was isolated from a seagrass collected in Setiu Lagoon, Terengganu. S2A1 was a Gram negative rod that was motile by means of a polar flagellum. Phenotypic and genotypic characterisation indicated that strain S2A1 represented a species in the genus Vibrio. The antimicrobial activities of S2A1 against a number of test microorganisms showed a broad antimicrobial spectrum property with inhibition towards 25 out of 29 test microorganisms. The antimicrobial compound(s of S2A1 was more effective against Gram-positive bacteria with 100% inhibition, compared to yeast (88.8% and Gram-negative bacteria (75.0% tested. High activity scores were observed when using whole cells compared to cell free extract.

  8. New features of the cell wall of the radio-resistant bacterium Deinococcus radiodurans.

    Science.gov (United States)

    Farci, Domenica; Bowler, Matthew W; Kirkpatrick, Joanna; McSweeney, Sean; Tramontano, Enzo; Piano, Dario

    2014-07-01

    We have analyzed the cell wall of the radio-resistant bacterium Deinococcus radiodurans. Unexpectedly, the bacterial envelope appears to be organized in different complexes of high molecular weight. Each complex is composed of several proteins, most of which are coded by genes of unknown function and the majority are constituents of the inner/outer membrane system. One of the most abundant complexes is constituted by the gene DR_0774. This protein is a type of secretin which is a known subunit of the homo-oligomeric channel that represents the main bulk of the type IV piliation family. Finally, a minor component of the pink envelope consists of several inner-membrane proteins. The implications of these findings are discussed.

  9. [Electrooptical properties of soil nitrogen-fixing bacterium Azospirillum brasilense: effect of copper ions].

    Science.gov (United States)

    Ignatov, O V; Kamnev, A A; Markina, L N; Antoniuk, L P; Kolina, M; Ignatov, V V

    2001-01-01

    The effects of copper ions on the uptake of some essential metals in the biomass and the electrooptical properties of cell suspensions of the nitrogen-fixing soil bacterium Azospirillum brasilense sp. 245 were studied. Copper cations were shown to be effectively taken up by the cell biomass from the culture medium. The addition of copper ions increased the rate of uptake of some other metals present in the culture medium. This was accompanied by changes in the electrooptical characteristics of cell suspension as measured within the orienting electric field frequency range of 10 to 10,000 kHz. The effects observed during short-term incubation of A. brasilense in the presence of copper cations were less significant than during long-term incubation. These results can be used for rapid screening of microbial cultures for enhanced efficiency of sorption and uptake of metals.

  10. A cultured greigite-producing magnetotactic bacterium in a novel group of sulfate-reducing bacteria.

    Science.gov (United States)

    Lefèvre, Christopher T; Menguy, Nicolas; Abreu, Fernanda; Lins, Ulysses; Pósfai, Mihály; Prozorov, Tanya; Pignol, David; Frankel, Richard B; Bazylinski, Dennis A

    2011-12-23

    Magnetotactic bacteria contain magnetosomes--intracellular, membrane-bounded, magnetic nanocrystals of magnetite (Fe(3)O(4)) or greigite (Fe(3)S(4))--that cause the bacteria to swim along geomagnetic field lines. We isolated a greigite-producing magnetotactic bacterium from a brackish spring in Death Valley National Park, California, USA, strain BW-1, that is able to biomineralize greigite and magnetite depending on culture conditions. A phylogenetic comparison of BW-1 and similar uncultured greigite- and/or magnetite-producing magnetotactic bacteria from freshwater to hypersaline habitats shows that these organisms represent a previously unknown group of sulfate-reducing bacteria in the Deltaproteobacteria. Genomic analysis of BW-1 reveals the presence of two different magnetosome gene clusters, suggesting that one may be responsible for greigite biomineralization and the other for magnetite. PMID:22194580

  11. New evidence for 250 Ma age of halotolerant bacterium from a Permian salt crystal

    Science.gov (United States)

    Satterfield, Cindy L.; Lowenstein, Tim K.; Vreeland, Russell H.; Rosenzweig, William D.; Powers, Dennis W.

    2005-04-01

    The purported oldest living organism, the spore-forming bacterium Virgibacillus sp. Permian strain 2 9-3, was recently cultured from a brine inclusion in halite of the 250 Ma Permian Salado Formation. However, the antiquity of Virgibacillus sp. 2 9-3 has been challenged; it has been argued that the halite crystal and the fluid inclusion from which the bacterial spores were extracted may be younger than the Permian Salado salts. Here we report that brine inclusions from the same layer of salt that housed Virgibacillus sp. 2 9-3 are composed of evaporated Late Permian seawater that was trapped in halite cement crystals precipitated syndepositionally from shallow groundwater brines at temperatures of 17 37 °C. These results support the 250 Ma age of the fluid inclusions, and by inference, the long-term survivability of microorganisms such as Virgibacillus sp. 2 9-3.

  12. [Isolation and characteristic of a moderately halophilic bacterium accumulated ectoine as main compatible solute].

    Science.gov (United States)

    He, Jian; Wang, Ting; Sun, Ji-Quan; Gu, Li-Feng; Li, Shun-Peng

    2005-12-01

    A moderately halophilic bacterium(designated strain I15) was isolated from lawn soil. Based on the analysis of 16S rDNA (GenBank accession number DQ010162), morphology, physiological and biochemical characteristics, strain I15 was identified as Virgibacillus marismortuii. This strain was capable of growing under 0% approximately 25% NaCl, and exhibited an optimum NaCl concentration of 10% and an optimum temperature of 30 degrees C and an optimum pH of 7.5 - 8.0 for its growth, respectively. Under hyperosmotic stress, strain 115 accumulated ectoine as the main compatible solute. Under 15% NaCl conditions the intracellar ectoine can reach to 1.608 mmol/(g x cdw), accounted for 89.6% of the total compatible solutes. The biosynthesis of ectoine was under the control of osmotic, and the accumulated ectoine synthesized intraceilularly can released under hypoosmotic shocks and resynthesis under hyperosmotic shock rapidly. PMID:16496700

  13. An outbreak in 1965 of severe respiratory illness caused by the Legionnaires' disease bacterium.

    Science.gov (United States)

    Thacker, S B; Bennett, J V; Tsai, T F; Fraser, D W; McDade, J E; Shepard, C C; Williams, K H; Stuart, W H; Dull, H B; Eickhoff, T C

    1978-10-01

    In January 1977 an unsolved outbreak of infection at St. Elizabeth's Hospital (Washington, D.C.) that occurred in 1965 was linked with Legionnaires' disease. The link was made by fluorescent antibody testing with the bacterium isolated from tissues of persons with Legionnaires' disease in the 1976 outbreak in Philadelphia. In July and August 1965, an epidemic of severe respiratory disease characterized by abrupt onset of high fever, weakness, malaise, and nonproductive cough, frequently accompanied by radiographic evidence of pneumonia, affected at least 81 patients at St. Elizabeth's Hospital, a general psychiatric hospital. Fourteen (17%) of the affected patients died. Intensive epidemiologic and laboratory investigations in 1965 did not determine the etiology. The etiologic organism may have become airborne from sites of soil excavation. PMID:361897

  14. Extraction and physicochemical characteristics of a red pigment produced by marine bacterium strain S-9801

    Institute of Scientific and Technical Information of China (English)

    田黎; 何培青; 刘晨临; 边际; 苗金来

    2002-01-01

    -- A red pigment that has better biological properties is produced by marine bacterium strain S- 9801. The extraction methods, physicochemical and toxicity of the pigment have been studied.Dissolubility of pigment in the five organic solvent has been tested, and ethanol is optimally chosen for extraction. Physicochemical characteristics of this pigment was stable. The absorbance of the pigment solution was no losing when put under natural light for 10 days or treated by UV for 30 minutes, color of the pigment unchanged after 100 ℃ hythere for 1 h or 80 ℃ xerother for 2 h. The median lethal dose (LD50) of the rat by celiac injection was 670.04 mg/kg and minimum lethal dose of oral was greater than 2 000 mg/kg.

  15. Bioluminescent reporter bacterium for toxicity monitoring in biological wastewater treatment systems

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, C.J.; Lajoie, C.A.; Layton, A.C.; Sayler, G.S.

    1999-01-01

    Toxic shock due to certain chemical loads in biological wastewater treatment systems can result in death of microorganisms and loss of floc structure. To overcome the limitations of existing approaches to toxicity monitoring, genes encoding enzymes for light production were inserted to a bacterium (Shk 1) isolated from activated sludge. The Shk 1 bioreporter indicated a toxic response to concentrations of cadmium, 2,4-dinitrophenol, and hydroquinone by reductions in initial levels of bioluminescence on exposure to the toxicant. The decrease in bioluminescence was more severe with increasing toxicant concentration. Bioluminescence did not decrease in response to ethanol concentrations up to 1,000 mg/L or to pH conditions between 6.1 and 7.9. A continuous toxicity monitoring system using this bioreporter was developed for influent wastewater and tested with hydroquinone. The reporter exhibited a rapid and proportional decrease in bioluminescence in response to increasing hydroquinone concentrations.

  16. Genomic Sequence of Burkholderia multivorans NKI379, a Soil Bacterium That Inhibits the Growth of Burkholderia pseudomallei

    OpenAIRE

    Hsueh, Pei-Tan; Liu, Jong-Kang; Chen, Ya-Lei; Liu, Pei-Ju; Ni, Wen-Fan; Chen, Yao-Shen; Wu, Keh-Ming; Lin, Hsi-Hsun

    2015-01-01

    Burkholderia multivorans NKI379 is a soil bacterium that exhibits an antagonistic effect against the growth of Burkholderia pseudomallei, the causative agent of the infectious disease melioidosis. We report the draft genomic sequence of B. multivorans NKI379, which has a G+C content of 67% and 5,203 candidate protein-encoding genes.

  17. Characterization of cytochrome P450 monooxygenase CYP154H1 from the thermophilic soil bacterium Thermobifida fusca

    NARCIS (Netherlands)

    Schallmey, Anett; den Besten, Gijs; Teune, Ite G. P.; Kembaren, Roga F.; Janssen, Dick B.

    2011-01-01

    Cytochrome P450 monooxygenases are valuable biocatalysts due to their ability to hydroxylate unactivated carbon atoms using molecular oxygen. We have cloned the gene for a new cytochrome P450 monooxygenase, named CYP154H1, from the moderately thermophilic soil bacterium Thermobifida fusca. The enzym

  18. Complete Genome Sequence of the Bacterium Aalborg_AAW-1, Representing a Novel Family within the Candidate Phylum SR1

    DEFF Research Database (Denmark)

    Dueholm, Morten Simonsen; Albertsen, Mads; Stokholm-Bjerregaard, Mikkel;

    2015-01-01

    Here, we present the complete genome sequence of the candidate phylum SR1 bacterium Aalborg_AAW-1. Its 16S rRNA gene is only 85.5% similar to that of the closest relative, RAAC1_SR1, and the genome of Aalborg_AAW-1 consequently represents the first of a novel family within the candidate phylum SR1....

  19. Complete Genome Sequence of Spiroplasma turonicum Tab4cT, a Bacterium Isolated from Horse Flies (Haematopota sp.)

    Science.gov (United States)

    Lo, Wen-Sui; Gasparich, Gail E.

    2016-01-01

    Spiroplasma turonicum Tab4cT was isolated from a horse fly (Haematopota sp.; probably Haematopota pluvialis) collected at Champchevrier, Indre-et-Loire, Touraine, France, in 1991. Here, we report the complete genome sequence of this bacterium to facilitate the investigation of its biology and the comparative genomics among Spiroplasma spp. PMID:27660788

  20. Differential proteome and cellular adhesion analyses of the probiotic bacterium Lactobacillus acidophilus NCFM grown on raffinose - an emerging prebiotic

    DEFF Research Database (Denmark)

    Celebioglu, Hasan Ufuk; Hansen, Morten Ejby; Majumder, Avishek;

    2016-01-01

    Whole cell and surface proteomes were analyzed together with adhesive properties of the probiotic bacterium Lactobacillus acidophilus NCFM (NCFM) grown on the emerging prebiotic raffinose, exemplifying a synbiotic. Adhesion of NCFM to mucin and intestinal HT-29 cells increased three-fold after...

  1. Complete Genome Sequence of Streptococcus salivarius HSISS4, a Human Commensal Bacterium Highly Prevalent in the Digestive Tract.

    Science.gov (United States)

    Mignolet, Johann; Fontaine, Laetitia; Kleerebezem, Michiel; Hols, Pascal

    2016-01-01

    The human commensal bacterium Streptococcus salivarius plays a major role in the equilibrium of microbial communities of the digestive tract. Here, we report the first complete genome sequence of a Streptococcus salivarius strain isolated from the small intestine, namely, HSISS4. Its circular chromosome comprises 1,903 coding sequences and 2,100,988 nucleotides. PMID:26847886

  2. Draft Genome Sequence of Lactobacillus delbrueckii subsp. bulgaricus CFL1, a Lactic Acid Bacterium Isolated from French Handcrafted Fermented Milk

    Science.gov (United States)

    Meneghel, Julie; Irlinger, Françoise; Loux, Valentin; Vidal, Marie; Passot, Stéphanie; Béal, Catherine; Layec, Séverine

    2016-01-01

    Lactobacillus delbrueckii subsp. bulgaricus (L. bulgaricus) is a lactic acid bacterium widely used for the production of yogurt and cheeses. Here, we report the genome sequence of L. bulgaricus CFL1 to improve our knowledge on its stress-induced damages following production and end-use processes. PMID:26941141

  3. Biological control of postharvest spoilage caused by Penicillium expansum and Botrytis cinerea in apple by using the bacterium Rahnella aquatilis.

    Science.gov (United States)

    Calvo, Juan; Calvente, Viviana; de Orellano, María Edith; Benuzzi, Delia; Sanz de Tosetti, Maria Isabel

    2007-02-15

    The epiphytic bacterium Rahnella aquatilis, isolated from fruit and leaves of apples, was tested for antagonistic properties against Penicillium expansum and Botrytis cinerea on Red Delicious apple fruit. In "in vitro" assays, this bacterium inhibited completely the germination of P. expansum and B. cinerea spores, but it needed direct contact with the spores to do it. However the putative mechanism seemed be different for the two pathogens. The bacterium did not produce extracellular antibiotic substances and when the acute toxicity test was performed no mortality, toxicity symptoms or organ alterations of the test animals (Wistar rats) were observed. Assays of biological control of P. expansum and B. cinerea on apple fruit were carried out at different temperatures. At 15 degrees C and 90% RH, the incidence of disease caused by P. expansum on apples stored for 20 days, was reduced by nearly 100% by R. aquatilis (10(6) cells/ml), while in the case of B. cinerea, the reduction of decay severity was nearly 64% but there was no reduction in the incidence of disease. At 4 degrees C and 90% RH the treatment with the bacterium significantly inhibited the development of B. cinerea on apples stored for 40 days and the incidence of disease was reduced by nearly 100%, while the incidence of disease caused by P. expansum at 4 degrees C was 60%. The results obtained show that R. aquatilis would be an interesting microorganism to be used as a biocontrol agent.

  4. Draft Genome Sequence of Lactobacillus delbrueckii subsp. bulgaricus CFL1, a Lactic Acid Bacterium Isolated from French Handcrafted Fermented Milk.

    Science.gov (United States)

    Meneghel, Julie; Dugat-Bony, Eric; Irlinger, Françoise; Loux, Valentin; Vidal, Marie; Passot, Stéphanie; Béal, Catherine; Layec, Séverine; Fonseca, Fernanda

    2016-03-03

    Lactobacillus delbrueckii subsp. bulgaricus (L. bulgaricus) is a lactic acid bacterium widely used for the production of yogurt and cheeses. Here, we report the genome sequence of L. bulgaricus CFL1 to improve our knowledge on its stress-induced damages following production and end-use processes.

  5. Draft Genome Sequence of Photorhabdus luminescens Strain BA1, an Entomopathogenic Bacterium Isolated from Nematodes Found in Egypt.

    Science.gov (United States)

    Ghazal, Shimaa; Hurst, Sheldon G; Morris, Krystalynne; Abebe-Akele, Feseha; Thomas, W Kelley; Badr, Usama M; Hussein, Mona A; Abouzaied, Mohamed A; Khalil, Kamal M; Tisa, Louis S

    2014-01-01

    Photorhabdus luminescens strain BA1 is an entomopathogenic bacterium that forms a symbiotic association with Heterorhabditis nematodes. We report here a 5.0-Mbp draft genome sequence for P. luminscens strain BA1, with a G+C content of 42.46% and 4,250 candidate protein-coding genes. PMID:24786955

  6. Draft Genome Sequence of Photorhabdus temperata Strain Meg1, an Entomopathogenic Bacterium Isolated from Heterorhabditis megidis Nematodes

    OpenAIRE

    Hurst, Sheldon G.; Ghazal, Shimaa; Morris, Krystalynne; Abebe-Akele, Feseha; Thomas, W Kelley; Badr, Usama M.; Hussein, Mona A.; AbouZaied, Mohamed A.; Khalil, Kamal M.; Tisa, Louis S.

    2014-01-01

    Photorhabdus temperata strain Meg1 is an entomopathogenic bacterium that forms a symbiotic association with Heterorhabditis nematodes. We report here a 4.9-Mbp draft genome sequence for P. temperata strain Meg1, with a G+C content of 43.18% and containing 4,340 candidate protein-coding genes.

  7. Draft Genome Sequence of Photorhabdus temperata Strain Meg1, an Entomopathogenic Bacterium Isolated from Heterorhabditis megidis Nematodes.

    Science.gov (United States)

    Hurst, Sheldon G; Ghazal, Shimaa; Morris, Krystalynne; Abebe-Akele, Feseha; Thomas, W Kelley; Badr, Usama M; Hussein, Mona A; AbouZaied, Mohamed A; Khalil, Kamal M; Tisa, Louis S

    2014-01-01

    Photorhabdus temperata strain Meg1 is an entomopathogenic bacterium that forms a symbiotic association with Heterorhabditis nematodes. We report here a 4.9-Mbp draft genome sequence for P. temperata strain Meg1, with a G+C content of 43.18% and containing 4,340 candidate protein-coding genes. PMID:25502670

  8. Draft Genome Sequence of Photorhabdus luminescens Strain BA1, an Entomopathogenic Bacterium Isolated from Nematodes Found in Egypt

    OpenAIRE

    Ghazal, Shimaa; Hurst, Sheldon G.; Morris, Krystalynne; Abebe-Akele, Feseha; Thomas, W Kelley; Badr, Usama M.; Hussein, Mona A.; AbouZaied, Mohamed A.; Khalil, Kamal M.; Tisa, Louis S.

    2014-01-01

    Photorhabdus luminescens strain BA1 is an entomopathogenic bacterium that forms a symbiotic association with Heterorhabditis nematodes. We report here a 5.0-Mbp draft genome sequence for P. luminscens strain BA1, with a G+C content of 42.46% and 4,250 candidate protein-coding genes.

  9. Antioxidants keep the potentially probiotic but highly oxygen-sensitive human gut bacterium Faecalibacterium prausnitzii alive at ambient air

    NARCIS (Netherlands)

    Khan, M. Tanweer; van Dijl, Jan Maarten; Harmsen, Hermie J M

    2014-01-01

    The beneficial human gut microbe Faecalibacterium prausnitzii is a 'probiotic of the future' since it produces high amounts of butyrate and anti-inflammatory compounds. However, this bacterium is highly oxygen-senstive, making it notoriously difficult to cultivate and preserve. This has so far precl

  10. Complete Genome Sequence of Streptococcus salivarius HSISS4, a Human Commensal Bacterium Highly Prevalent in the Digestive Tract

    Science.gov (United States)

    Fontaine, Laetitia; Kleerebezem, Michiel

    2016-01-01

    The human commensal bacterium Streptococcus salivarius plays a major role in the equilibrium of microbial communities of the digestive tract. Here, we report the first complete genome sequence of a Streptococcus salivarius strain isolated from the small intestine, namely, HSISS4. Its circular chromosome comprises 1,903 coding sequences and 2,100,988 nucleotides. PMID:26847886

  11. A Comparative biochemical study on two marine endophytes, Bacterium SRCnm and Bacillus sp. JS, Isolated from red sea algae.

    Science.gov (United States)

    Ahmed, Eman Fadl; Hassan, Hossam Mokhtar; Rateb, Mostafa Ezzat; Abdel-Wahab, Noha; Sameer, Somayah; Aly Taie, Hanan Anwar; Abdel-Hameed, Mohammed Sayed; Hammouda, Ola

    2016-01-01

    Two marine endophytic bacteria were isolated from the Red Sea algae; a red alga; Acanthophora dendroides and the brown alga Sargassum sabrepandum. The isolates were identified based on their 16SrRNA sequences as Bacterium SRCnm and Bacillus sp. JS. The objective of this study was to investigate the potential anti-microbial and antioxidant activities of the extracts of the isolated bacteria grown in different nutrient conditions. Compared to amoxicillin (25μg/disk) and erythromycin (15μg/disk), the extracts of Bacterium SRCn min media II, III, IV and V were potent inhibitors of the gram-positive bacterium Sarcina maxima even at low concentrations. Also, the multidrug resistant Staphylococcus aureus(MRSA) was more sensitive to the metabolites produced in medium (II) of the same endophyte than erythromycin (15μg/disk). A moderate activity of the Bacillus sp. JS extracts of media I and II was obtained against the same pathogen. The total compounds (500ug/ml) of both isolated endophytes showed moderate antioxidant activities (48.9% and 46.1%, respectively). LC/MS analysis of the bacterial extracts was carried out to investigate the likely natural products produced. Cyclo(D-cis-Hyp-L-Leu), dihydrosphingosine and 2-Amino-1,3-hexadecanediol were identified in the fermentation medium of Bacterium SRCnm, whereas cyclo (D-Pro-L-Tyr) and cyclo (L-Leu-L-Pro) were the suggested compounds of Bacillus sp. JS. PMID:26826831

  12. Complete genome of Pandoraea pnomenusa RB-38, an oxalotrophic bacterium isolated from municipal solid waste landfill site.

    Science.gov (United States)

    Lim, Yan-Lue; Ee, Robson; Yong, Delicia; Tee, Kok-Keng; Yin, Wai-Fong; Chan, Kok-Gan

    2015-11-20

    Pandoraea pnomenusa RB-38 is a bacterium isolated from a former sanitary landfill site. Here, we present the complete genome of P. pnomenusa RB38 in which an oxalate utilization pathway was identified. The genome analysis suggested the potential of this strain as an effective biocontrol agent against oxalate-producing phytopathogens. PMID:26393955

  13. Draft Genome Sequence of the Extremely Halophilic Bacterium Halomonas salina Strain CIFRI1, Isolated from the East Coast of India

    OpenAIRE

    Behera, Bijay Kumar; Das, Priyanka; Maharana, Jitendra; Paria, Prasenjit; Mandal, Shambhu Nath; Meena, Dharmendra Kumar; Sharma, Anil Prakash; Jayarajan, Rijith; Dixit, Vishal; Verma, Ankit; Vellarikkal, Shamsudheen Karuthedath; Scaria, Vinod; Sivasubbu, Sridhar; Rao, Atmakuri Ramakrishna; Mohapatra, Trilochan

    2015-01-01

    Halomonas salina strain CIFRI1 is an extremely salt-stress-tolerant bacterium isolated from the salt crystals of the east coast of India. Here we report the annotated 3.45-Mb draft genome sequence of strain CIFRI1 having 86 contigs with 3,139 protein coding loci, including 62 RNA genes.

  14. Complete Genome Sequence of Raoultella ornithinolytica Strain S12, a Lignin-Degrading Bacterium Isolated from Forest Soil.

    Science.gov (United States)

    Bao, Wenying; Zhou, Yun; Jiang, Jingwei; Xu, Zhihui; Hou, Liyuan; Leung, Frederick Chi-Ching

    2015-03-19

    We report the complete genome sequence of Raoultella ornithinolytica strain S12, isolated from a soil sample collected from areas bordering rotten wood and wet soil on Mt. Zijin, Nanjing. The complete genome of this bacterium may contribute toward the discovery of efficient lignin-degrading pathways.

  15. Whole-Genome Shotgun Sequence of the Keratinolytic Bacterium Lysobacter sp. A03, Isolated from the Antarctic Environment

    OpenAIRE

    Pereira, Jamile Queiroz; Ambrosini, Adriana; Sant’Anna, Fernando Hayashi; Tadra-Sfeir, Michele; Faoro, Helisson; Pedrosa, Fábio de Oliveira; Souza, Emanuel Maltempi; Adriano BRANDELLI; Passaglia, Luciane M. P.

    2015-01-01

    Lysobacter sp. strain A03 is a protease-producing bacterium isolated from decomposing-penguin feathers collected in the Antarctic environment. This strain has the ability to degrade keratin at low temperatures. The A03 genome sequence provides the possibility of finding new genes with biotechnological potential to better understand its cold-adaptation mechanism and survival in cold environments.

  16. Whole-Genome Shotgun Sequence of the Keratinolytic Bacterium Lysobacter sp. A03, Isolated from the Antarctic Environment.

    Science.gov (United States)

    Pereira, Jamile Queiroz; Ambrosini, Adriana; Sant'Anna, Fernando Hayashi; Tadra-Sfeir, Michele; Faoro, Helisson; Pedrosa, Fábio Oliveira; Souza, Emanuel Maltempi; Brandelli, Adriano; Passaglia, Luciane M P

    2015-01-01

    Lysobacter sp. strain A03 is a protease-producing bacterium isolated from decomposing-penguin feathers collected in the Antarctic environment. This strain has the ability to degrade keratin at low temperatures. The A03 genome sequence provides the possibility of finding new genes with biotechnological potential to better understand its cold-adaptation mechanism and survival in cold environments. PMID:25838495

  17. Complete Genome Sequence of Spiroplasma turonicum Tab4cT, a Bacterium Isolated from Horse Flies (Haematopota sp.).

    Science.gov (United States)

    Lo, Wen-Sui; Gasparich, Gail E; Kuo, Chih-Horng

    2016-01-01

    Spiroplasma turonicum Tab4c(T) was isolated from a horse fly (Haematopota sp.; probably Haematopota pluvialis) collected at Champchevrier, Indre-et-Loire, Touraine, France, in 1991. Here, we report the complete genome sequence of this bacterium to facilitate the investigation of its biology and the comparative genomics among Spiroplasma spp. PMID:27660788

  18. Draft Genome Sequence of Lactobacillus delbrueckii subsp. bulgaricus CFL1, a Lactic Acid Bacterium Isolated from French Handcrafted Fermented Milk.

    Science.gov (United States)

    Meneghel, Julie; Dugat-Bony, Eric; Irlinger, Françoise; Loux, Valentin; Vidal, Marie; Passot, Stéphanie; Béal, Catherine; Layec, Séverine; Fonseca, Fernanda

    2016-01-01

    Lactobacillus delbrueckii subsp. bulgaricus (L. bulgaricus) is a lactic acid bacterium widely used for the production of yogurt and cheeses. Here, we report the genome sequence of L. bulgaricus CFL1 to improve our knowledge on its stress-induced damages following production and end-use processes. PMID:26941141

  19. Towards the entire proteome of the model bacterium Bacillus subtilis by gel-based and gel-free approaches

    NARCIS (Netherlands)

    Wolff, Susanne; Antelmann, Haike; Albrecht, Dirk; Becher, Doerte; Bernhardt, Joerg; Bron, Sierd; Buettner, Knut; van Dijl, Jan Maarten; Eymann, Christine; Otto, Andreas; Tam, Le Thi; Hecker, Michael

    2007-01-01

    With the emergence of mass spectrometry in protein science and the availability of complete genome sequences, proteomics has gone through a rapid development. The soil bacterium Bacillus subtilis, as one of the first DNA sequenced species, represents a model for Gram-positive bacteria and its proteo

  20. THE ENDOPHYTE CURTOBACTERIUM FLACCUMFACIENS REDUCES SYMPTOMS CAUSED BY XYLELLA FASTIDIOSA IN CATHARANTHUS ROSEUSAN ENDOPHYTIC BACTERIUM FROM CITRUS

    Science.gov (United States)

    Citrus variegated chlorosis (CVC) is a disease of sweet orange (Citrus sinensis (L.)) caused by Xylella fastidiosa subsp. pauca, a phytopathogenic bacterium that can infect all sweet orange cultivars. Sweet orange trees are sometimes observed to be infected by Xylella fastidiosa without showing seve...

  1. Draft Genome Sequence of Bacillus pseudalcaliphilus PN-137T (DSM 8725), an Alkaliphilic Halotolerant Bacterium Isolated from Garden Soils.

    Science.gov (United States)

    Wang, Jie-Ping; Liu, Bo; Liu, Guo-Hong; Xiao, Rong-Feng; Zheng, Xue-Fang; Shi, Huai; Ge, Ci-Bin

    2015-01-01

    Bacillus pseudalcaliphilus PN-137(T) (DSM 8725) is a Gram-positive, spore-forming, alkaliphilic, and halotolerant bacterium. Here, we report the 4.49-Mb genome sequence of B. pseudalcaliphilus PN-137(T), which will accelerate the application of this alkaliphile and provide useful information for genomic taxonomy and phylogenomics of Bacillus-like bacteria.

  2. Draft Genome Sequence of Nitrosospira sp. Strain APG3, a Psychrotolerant Ammonia-Oxidizing Bacterium Isolated from Sandy Lake Sediment

    OpenAIRE

    Garcia, Juan C.; Urakawa, Hidetoshi; Le, Vang Q.; Stein, Lisa Y.; Klotz, Martin G; Nielsen, Jeppe L.

    2013-01-01

    Bacteria in the genus Nitrosospira play vital roles in the nitrogen cycle. Nitrosospira sp. strain APG3 is a psychrotolerant betaproteobacterial ammonia-oxidizing bacterium isolated from freshwater lake sediment. The draft genome revealed that it represents a new species of cluster 0 Nitrosospira, which is presently not represented by described species.

  3. Complete Genome Sequence of Dyella thiooxydans ATSB10, a Thiosulfate-Oxidizing Bacterium Isolated from Sunflower Fields in South Korea.

    Science.gov (United States)

    Hwangbo, Kyeong; Um, Yurry; Chung, Hee; Yoo, Jemin; Kim, Ki Yoon; Madhaiyan, Munusamy; Sa, Tong Min; Lee, Yi

    2016-01-01

    Dyella thiooxydans ATSB10 (KACC 12756(T) = LMG 24673(T)) is a thiosulfate-oxidizing bacterium isolated from rhizosphere soils of sunflower plants. In this study, we completely sequenced the genome of D. thiooxydans ATSB10 and identified the genes involved in thiosulfate oxidation and the metabolism of aromatic intermediates. PMID:27340060

  4. Draft Genome Sequence of Anaeromyxobacter sp. Strain PSR-1, an Arsenate-Respiring Bacterium Isolated from Arsenic-Contaminated Soil

    OpenAIRE

    Tonomura, Mimori; Ehara, Ayaka; Suzuki, Haruo; Amachi, Seigo

    2015-01-01

    Here, we report a draft genome sequence of Anaeromyxobacter sp. strain PSR-1, an arsenate-respiring bacterium isolated from arsenic-contaminated soil. It contained three distinct arsenic resistance gene clusters (ars operons), while no respiratory arsenate reductase gene (arr) was identified.

  5. Genome Sequence of Pseudomonas sp. Strain S9, an Extracellular Arylsulfatase-Producing Bacterium Isolated from Mangrove Soil ▿

    OpenAIRE

    Long, Mengxian; Ruan, Lingwei; Yu, Ziniu; Xu, Xun

    2011-01-01

    Pseudomonas sp. strain S9 was originally isolated from mangrove soil in Xiamen, China. It is an aerobic bacterium which shows extracellular arylsulfatase activity. Here, we describe the 4.8-Mb draft genome sequence of Pseudomonas sp. S9, which exhibits novel cysteine-type sulfatases.

  6. Complete Genome Sequence of Raoultella ornithinolytica Strain S12, a Lignin-Degrading Bacterium Isolated from Forest Soil

    OpenAIRE

    Bao, Wenying; Zhou, Yun; Jiang, Jingwei; Xu, Zhihui; Hou, Liyuan; Leung, Frederick Chi-Ching

    2015-01-01

    We report the complete genome sequence of Raoultella ornithinolytica strain S12, isolated from a soil sample collected from areas bordering rotten wood and wet soil on Mt. Zijin, Nanjing. The complete genome of this bacterium may contribute toward the discovery of efficient lignin-degrading pathways.

  7. Genome Sequence of Virgibacillus pantothenticus DSM 26T (ATCC 14576), a Mesophilic and Halotolerant Bacterium Isolated from Soil.

    Science.gov (United States)

    Wang, Jie-Ping; Liu, Bo; Liu, Guo-Hong; Chen, De-Ju; Zhu, Yu-Jing; Chen, Zheng; Che, Jian-Mei

    2015-01-01

    Virgibacillus pantothenticus DSM 26(T) is a Gram-positive, spore-forming, aerobic, mesophilic, and halotolerant bacterium. Here, we report its 4.76-Mb draft genome sequence, which is the first genome information of V. pantothenticus and will promote biological research and biotechnological application for the species. PMID:26383648

  8. Genome Sequence of Virgibacillus pantothenticus DSM 26T (ATCC 14576), a Mesophilic and Halotolerant Bacterium Isolated from Soil

    OpenAIRE

    Wang, Jie-ping; Liu, Bo; Liu, Guo-hong; Chen, De-ju; Zhu, Yu-jing; Chen, Zheng; Che, Jian-mei

    2015-01-01

    Virgibacillus pantothenticus DSM 26T is a Gram-positive, spore-forming, aerobic, mesophilic, and halotolerant bacterium. Here, we report its 4.76-Mb draft genome sequence, which is the first genome information of V. pantothenticus and will promote biological research and biotechnological application for the species.

  9. The use of fluorescent probes to assess viability of the plant pathogenic bacterium Clavibacter michiganensis subsp. michiganensis by flow cytometry

    NARCIS (Netherlands)

    Chitarra, L.G.; Breeuwer, P.; Abee, T.; Bulk, van den R.W.

    2006-01-01

    Determination of the viability of bacteria by the conventional plating technique is a time-consuming process. Methods based on enzyme activity or membrane integrity are much faster and may be good alternatives. Assessment of the viability of suspensions of the plant pathogenic bacterium Clavibacter

  10. Methanol coneversion by a novel thermophilic homoacetogenic bacterium Moorella mulderi sp.nov. isolated from a bioreactor

    NARCIS (Netherlands)

    Balk, M.; Weijma, J.; Friedrich, M.W.; Stams, A.J.M.

    2003-01-01

    A thermophilic, anaerobic, spore-forming bacterium (strain TMS) was isolated from a thermophilic bioreactor operated at 65 degreesC with methanol as the energy source. Cells were gram-positive straight rods, 0.4-0.6 mum x 2-8 mum, growing as single cells or in pairs. The temperature range for growth

  11. Metabolism of Kaempferia parviflora polymethoxyflavones by human intestinal bacterium Bautia sp. MRG-PMF1.

    Science.gov (United States)

    Kim, Mihyang; Kim, Nayoung; Han, Jaehong

    2014-12-24

    Poylmethoxyflavones (PMFs) are major bioactive flavonoids, which exhibit various biological activities, such as anticancer effects. The biotransformation of PMFs and characterization of a PMF-metabolizing human intestinal bacterium were studied herein for the first time. Hydrolysis of aryl methyl ether functional groups by human fecal samples was observed from the bioconversion of various PMFs. Activity-guided screening for PMF-metabolizing intestinal bacteria under anaerobic conditions resulted in the isolation of a strict anaerobic bacterium, which was identified as Blautia sp. MRG-PMF1. The isolated MRG-PMF1 was able to metabolize various PMFs to the corresponding demethylated flavones. The microbial conversion of bioactive 5,7-dimethoxyflavone (5,7-DMF) and 5,7,4'-trimethoxyflavone (5,7,4'-TMF) was studied in detail. 5,7-DMF and 5,7,4'-TMF were completely metabolized to 5,7-dihydroxyflavone (chrysin) and 5,7,4'-trihydroxyflavone (apigenin), respectively. From a kinetics study, the methoxy group on the flavone C-7 position was found to be preferentially hydrolyzed. 5-Methoxychrysin, the intermediate of 5,7-DMF metabolism by Blautia sp. MRG-PMF1, was isolated and characterized by nuclear magnetic resonance spectroscopy. Apigenin was produced from the sequential demethylation of 5,7,4'-TMF, via 5,4'-dimethoxy-7-hydroxyflavone and 7,4'-dihydroxy-5-methoxyflavone (thevetiaflavone). Not only demethylation activity but also deglycosylation activity was exhibited by Blautia sp. MRG-PMF1, and various flavonoids, including isoflavones, flavones, and flavanones, were found to be metabolized to the corresponding aglycones. The unprecedented PMF demethylation activity of Blautia sp. MRG-PMF1 will expand our understanding of flavonoid metabolism in the human intestine and lead to novel bioactive compounds. PMID:25437273

  12. Co-metabolism of DDT by the newly isolated bacterium, Pseudoxanthomonas sp. wax

    Directory of Open Access Journals (Sweden)

    Guangli Wang

    2010-06-01

    Full Text Available Microbial degradation of 1,1,1-trichloro-2,2-bis(p-chlorophenylethane (DDT is the most promising way to clean up DDT residues found in the environment. In this paper, a bacterium designated as wax, which was capable of co-metabolizing DDT with other carbon sources, was isolated from a long-term DDT-contaminated soil sample by an enrichment culture technique. The new isolate was identified as a member of the Pseudoxanthomonas sp., based on its morphological, physiological and biochemical properties, as well as by 16S rRNA gene analysis. In the presence of 100 mg l-1 glucose, the wax strain could degrade over 95% of the total DDT, at a concentration of 20 mg l-1, in 72 hours, and could degrade over 60% of the total DDT, at a concentration of 100 mg l-1, in 144 hours. The wax strain had the highest degradation efficiency among all of the documented DDT-degrading bacteria. The wax strain could efficiently degrade DDT at temperatures ranging from 20 to 37ºC, and with initial pH values ranging from 7 to 9. The bacterium could also simultaneously co-metabolize 1,1-dichloro-2,2-bis(p-chlorophenylethane (DDD, 2,2-bis(p-chlorophenyl-1,1-dichlorethylene (DDE, and other organochlorine compounds. The wax strain could also completely remove 20 mg kg-1 of DDT from both sterile and non-sterile soils in 20 days. This study demonstrates the significant potential use of Pseudoxanthomonas sp. wax for the bioremediation of DDT in the environment.

  13. Virgibacillus salarius sp. nov., a halophilic bacterium isolated from a Saharan salt lake.

    Science.gov (United States)

    Hua, Ngoc-Phuc; Hamza-Chaffai, Amel; Vreeland, Russell H; Isoda, Hiroko; Naganuma, Takeshi

    2008-10-01

    A Gram-positive, endospore-forming, rod-shaped and moderately halophilic bacterium was isolated from a salt-crust sample collected from Gharsa salt lake (Chott el Gharsa), Tunisia. The newly isolated bacterium, designated SA-Vb1(T), was identified based on polyphasic taxonomy including genotypic, phenotypic and chemotaxonomic characterization. Strain SA-Vb1(T) was closely related to the type strains of Virgibacillus marismortui and Virgibacillus olivae, with 16S rRNA gene sequence similarities of 99.7 and 99.4 %, respectively. However, strain SA-Vb1(T) was distinguished from these two type strains on the basis of phenotypic characteristics and DNA-DNA relatedness (29.4 and 5.1 %, respectively). The genetic relationship between strain SA-Vb1(T) and Virgibacillus pantothenticus IAM 11061(T) (the type strain of the type species) and other type strains of the genus was 96-98 % based on 16S rRNA gene sequence similarity and 18.3-22.3 % based on DNA-DNA hybridization. Biochemical analysis resulted in determination of major fatty acids iso-C(15 : 0), anteiso-C(15 : 0) and anteiso-C(17 : 0) (33.3, 29.2 and 9.8 %, respectively); phosphatidylglycerol, diphosphatidylglycerol and phosphatidylethanolamine were the main polar lipids and MK-7 was the predominant menaquinone ( approximately 100 %). The distinct characteristics demonstrated by strain SA-Vb1(T) represent properties of a novel species of the genus Virgibacillus, for which the name Virgibacillus salarius sp. nov. is proposed. The type strain is SA-Vb1(T) (=JCM 12946(T) =DSM 18441(T)). PMID:18842865

  14. Solution and crystal structure of BA42, a protein from the Antarctic bacterium Bizionia argentinensis comprised of a stand-alone TPM domain.

    Science.gov (United States)

    Aran, Martin; Smal, Clara; Pellizza, Leonardo; Gallo, Mariana; Otero, Lisandro H; Klinke, Sebastián; Goldbaum, Fernando A; Ithurralde, Esteban R; Bercovich, Andrés; Mac Cormack, Walter P; Turjanski, Adrián G; Cicero, Daniel O

    2014-11-01

    The structure of the BA42 protein belonging to the Antarctic flavobacterium Bizionia argentinensis was determined by nuclear magnetic resonance and X-ray crystallography. This is the first structure of a member of the PF04536 family comprised of a stand-alone TPM domain. The structure reveals a new topological variant of the four β-strands constituting the central β-sheet of the αβα architecture and a double metal binding site stabilizing a pair of crossing loops, not observed in previous structures of proteins belonging to this family. BA42 shows differences in structure and dynamics in the presence or absence of bound metals. The affinity for divalent metal ions is close to that observed in proteins that modulate their activity as a function of metal concentration, anticipating a possible role for BA42.

  15. Enhanced bactericidal potency of nanoliposomes by modification of the fusion activity between liposomes and bacterium

    Directory of Open Access Journals (Sweden)

    Ma YF

    2013-06-01

    Full Text Available Yufan Ma,1 Zhao Wang,1,2 Wen Zhao,1 Tingli Lu,1 Rutao Wang,1,2 Qibing Mei,1 Tao Chen1–3 1Key Laboratory for Space Bioscience and Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, People's Republic of China; 2Shaanxi Liposome Research Center, Xi'an, Shaanxi, People's Republic of China; 3Xi'an Libang Pharmaceuticals Co, Ltd, Xi'an, People's Republic of China Background: Pseudomonas aeruginosa represents a good model of antibiotic resistance. These organisms have an outer membrane with a low level of permeability to drugs that is often combined with multidrug efflux pumps, enzymatic inactivation of the drug, or alteration of its molecular target. The acute and growing problem of antibiotic resistance of Pseudomonas to conventional antibiotics made it imperative to develop new liposome formulations to overcome these mechanisms, and investigate the fusion between liposome and bacterium. Methods: The rigidity, stability and charge properties of phospholipid vesicles were modified by varying the cholesterol, 1,2-dioleoyl-sn-glycero-3-phosphatidylethanolamine (DOPE, and negatively charged lipids 1,2-dimyristoyl-sn-glycero-3-phosphoglycerol sodium salt (DMPG, 1,2-dimyristoyl-sn-glycero-3-phopho-L-serine sodium salt (DMPS, 1,2-dimyristoyl-sn-glycero-3-phosphate monosodium salt (DMPA, nature phosphatidylserine sodium salt from brain and nature phosphatidylinositol sodium salt from soybean concentrations in liposomes. Liposomal fusion with intact bacteria was monitored using a lipid-mixing assay. Results: It was discovered that the fluid liposomes-bacterium fusion is not dependent on liposomal size and lamellarity. A similar degree of fusion was observed for liposomes with a particle size from 100 to 800 nm. The fluidity of liposomes is an essential pre-request for liposomes fusion with bacteria. Fusion was almost completely inhibited by incorporation of cholesterol into fluid liposomes. The increase in the

  16. A Novel Treatment Protects Chlorella at Commercial Scale from the Predatory Bacterium Vampirovibrio chlorellavorus.

    Science.gov (United States)

    Ganuza, Eneko; Sellers, Charles E; Bennett, Braden W; Lyons, Eric M; Carney, Laura T

    2016-01-01

    The predatory bacterium, Vampirovibrio chlorellavorus, can destroy a Chlorella culture in just a few days, rendering an otherwise robust algal crop into a discolored suspension of empty cell walls. Chlorella is used as a benchmark for open pond cultivation due to its fast growth. In nature, V. chlorellavorus plays an ecological role by controlling this widespread terrestrial and freshwater microalga, but it can have a devastating effect when it attacks large commercial ponds. We discovered that V. chlorellavorus was associated with the collapse of four pilot commercial-scale (130,000 L volume) open-pond reactors. Routine microscopy revealed the distinctive pattern of V. chlorellavorus attachment to the algal cells, followed by algal cell clumping, culture discoloration and ultimately, growth decline. The "crash" of the algal culture coincided with increasing proportions of 16s rRNA sequencing reads assigned to V. chlorellavorus. We designed a qPCR assay to predict an impending culture crash and developed a novel treatment to control the bacterium. We found that (1) Chlorella growth was not affected by a 15 min exposure to pH 3.5 in the presence of 0.5 g/L acetate, when titrated with hydrochloric acid and (2) this treatment had a bactericidal effect on the culture (2-log decrease in aerobic counts). Therefore, when qPCR results indicated a rise in V. chlorellavorus amplicons, we found that the pH-shock treatment prevented the culture crash and doubled the productive longevity of the culture. Furthermore, the treatment could be repeatedly applied to the same culture, at the beginning of at least two sequential batch cycles. In this case, the treatment was applied preventively, further increasing the longevity of the open pond culture. In summary, the treatment reversed the infection of V. chlorellavorus as confirmed by observations of bacterial attachment to Chlorella cells and by detection of V. chlorellavorus by 16s rRNA sequencing and qPCR assay. The p

  17. Computational prediction of essential genes in an unculturable endosymbiotic bacterium, Wolbachia of Brugia malayi

    Directory of Open Access Journals (Sweden)

    Carlow Clotilde KS

    2009-11-01

    Full Text Available Abstract Background Wolbachia (wBm is an obligate endosymbiotic bacterium of Brugia malayi, a parasitic filarial nematode of humans and one of the causative agents of lymphatic filariasis. There is a pressing need for new drugs against filarial parasites, such as B. malayi. As wBm is required for B. malayi development and fertility, targeting wBm is a promising approach. However, the lifecycle of neither B. malayi nor wBm can be maintained in vitro. To facilitate selection of potential drug targets we computationally ranked the wBm genome based on confidence that a particular gene is essential for the survival of the bacterium. Results wBm protein sequences were aligned using BLAST to the Database of Essential Genes (DEG version 5.2, a collection of 5,260 experimentally identified essential genes in 15 bacterial strains. A confidence score, the Multiple Hit Score (MHS, was developed to predict each wBm gene's essentiality based on the top alignments to essential genes in each bacterial strain. This method was validated using a jackknife methodology to test the ability to recover known essential genes in a control genome. A second estimation of essentiality, the Gene Conservation Score (GCS, was calculated on the basis of phyletic conservation of genes across Wolbachia's parent order Rickettsiales. Clusters of orthologous genes were predicted within the 27 currently available complete genomes. Druggability of wBm proteins was predicted by alignment to a database of protein targets of known compounds. Conclusion Ranking wBm genes by either MHS or GCS predicts and prioritizes potentially essential genes. Comparison of the MHS to GCS produces quadrants representing four types of predictions: those with high confidence of essentiality by both methods (245 genes, those highly conserved across Rickettsiales (299 genes, those similar to distant essential genes (8 genes, and those with low confidence of essentiality (253 genes. These data facilitate

  18. Halomonas urumqiensis sp. nov., a moderately halophilic bacterium isolated from a saline-alkaline lake.

    Science.gov (United States)

    Zhang, Shanshan; Pan, Jiao; Lu, Weidong; Yan, Yanchun; Wang, Haisheng; Wiegel, Jurgen; Zhao, Baisuo

    2016-05-01

    A moderately halophilic, aerobic bacterium, strain BZ-SZ-XJ27T, belonging to the genus Halomonas, was isolated from a saline-alkaline lake in the Xinjiang Uyghur Autonomous Region of China. Phylogenetic analysis based on 16S rRNA gene sequences and a multilocus sequence analysis using the 16S rRNA, gyrB and rpoD genes demonstrated that strain BZ-SZ-XJ27T represents a member of the genus Halomonas. On the basis of 16S rRNA gene sequence similarity, the closest relatives were Halomonas campaniensis 5AGT, H. fontilapidosi 5CRT, H. korlensis XK1T and H. sinaiensis ALO SharmT, with similarities of 96.2-97.2 %. DNA-DNA hybridization with H. korlensis CGMCC 1.6981T (the nearest phylogenetic neighbour) and H. campaniensis DSM 15293T (the highest 16S rRNA gene sequence similarity) showed relatedness values of 53 and 38 %, respectively, demonstrating the separateness of the three taxa. The bacterium stained Gram-negative and the cells were motile and rod-shaped. The strain formed creamy-white colonies and grew under optimal conditions of 1.42 M Na+ (range 0.22-4.32 M Na+), pH 8.0-8.5 (range pH 6.0-10.0) and 39 °C (range 4-43 °C). The dominant fatty acids were summed feature 8 (C18 : 1ω7c/C18 : 1ω6c; 36.6 %), C16 : 0 (25.9 %) and summed feature 3 (C16 : 1ω7c/C16 : 1ω6c; 21.2 %). The dominant polar lipids were two unknown phospholipids, phosphatidylethanolamine and phosphatidylglycerol, and the main respiratory quinones were ubiquinone 9 (Q-9; 89 %) and ubiquinone 8 (Q-8; 10 %). The genomic DNA G+C content was 61.7 ± 0.8 mol% (Tm). On the basis of phenotypic, chemotaxonomic and phylogenetic features, strain BZ-SZ-XJ27T is proposed to represent a novel species, Halomonas urumqiensis sp. nov., within the genus Halomonas of the family Halomonadaceae. The type strain is BZ-SZ-XJ27T ( = JCM 30202T = CGMCC 1.12917T). PMID:26873696

  19. Sequencing and characterization of the xyl operon of a gram-positive bacterium, Tetragenococcus halophila.

    Science.gov (United States)

    Takeda, Y; Takase, K; Yamato, I; Abe, K

    1998-07-01

    The xyl operon of a gram-positive bacterium, Tetragenococcus halophila (previously called Pediococcus halophilus), was cloned and sequenced. The DNA was about 7.7 kb long and contained genes for a ribose binding protein and part of a ribose transporter, xylR (a putative regulatory gene), and the xyl operon, along with its regulatory region and transcription termination signal, in this order. The DNA was AT rich, the GC content being 35.8%, consistent with the GC content of this gram-positive bacterium. The xyl operon consisted of three genes, xylA, encoding a xylose isomerase, xylB, encoding a xylulose kinase, and xylE, encoding a xylose transporter, with predicted molecular weights of 49,400, 56,400, and 51,600, respectively. The deduced amino acid sequences of the XylR, XylA, XylB, and XylE proteins were similar to those of the corresponding proteins in other gram-positive and -negative bacteria, the similarities being 37 to 64%. Each polypeptide of XylB and XylE was expressed functionally in Escherichia coli. XylE transported D-xylose in a sodium ion-dependent manner, suggesting that it is the first described xylose/Na+ symporter. The XylR protein contained a consensus sequence for binding catabolites of glucose, such as glucose-6-phosphate, which has been discovered in glucose and fructose kinases in bacteria. Correspondingly, the regulatory region of this operon contained a putative binding site of XylR with a palindromic structure. Furthermore, it contained a consensus sequence, CRE (catabolite-responsive element), for binding CcpA (catabolite control protein A). We speculate that the transcriptional regulation of this operon resembles the regulation of catabolite-repressible operons such as the amy, lev, xyl, and gnt operons in various gram-positive bacteria. We discuss the significance of the regulation of gene expression of this operon in T. halophila. PMID:9647823

  20. Production of polyhydroxybutyrate by the marine photosynthetic bacterium Rhodovulum sulfidophilum P5

    Institute of Scientific and Technical Information of China (English)

    CAI Jinling; WEI Ying; ZHAO Yupeng; PAN Guanghua; WANG Guangce

    2012-01-01

    The effects of different NaCl concentrations,nitrogen sources,carbon sources,and carbon to nitrogen molar ratios on biomass accumulation and polyhydroxybutyrate (PHB) production were studied in batch cultures of the marine photosynthetic bacterium Rhodovulum sulfidophilum P5 under aerobic-dark conditions.The results show that the accumulation of PHB in strain P5 is a growth-associated process.Strain P5 had maximum biomass and PHB accumulation at 2%-3% NaCl,suggesting that the bacterium can maintain growth and potentially produce PHB at natural seawater salinity.In the nitrogen source test,the maximum biomass accumulation (8.10±0.09 g/L) and PHB production (1.11±0.13 g/L and 14.62%±2.25%of the cell dry weight) were observed when peptone and ammonium chloride were used as the sole nitrogen source.NH+4-N was better for PHB production than other nitrogen sources.In the carbon source test,the maximum biomass concentration (7.65±0.05 g/L) was obtained with malic acid as the sole carbon source,whereas the maximum yield of PHB (5.03±0.18 g/L and 66.93%±1.69% of the cell dry weight) was obtained with sodium pyruvate as the sole carbon source.In the carbon to nitrogen ratios test,sodium pyruvate and ammonium chloride were selected as the carbon and nitrogen sources,respectively.The best carbon to nitrogen molar ratio for biomass accumulation (8.77±0.58 g/L) and PHB production (6.07±0.25 g/L and 69.25%±2.05% of the cell dry weight) was 25.The results provide valuable data on the production of PHB by R.sulfidophilum P5 and further studies are on-going for best cell growth and PHB yield.

  1. Complete genome sequence of the filamentous anoxygenic phototrophic bacterium Chloroflexus aurantiacus

    Directory of Open Access Journals (Sweden)

    Larimer Frank W

    2011-06-01

    Full Text Available Abstract Background Chloroflexus aurantiacus is a thermophilic filamentous anoxygenic phototrophic (FAP bacterium, and can grow phototrophically under anaerobic conditions or chemotrophically under aerobic and dark conditions. According to 16S rRNA analysis, Chloroflexi species are the earliest branching bacteria capable of photosynthesis, and Cfl. aurantiacus has been long regarded as a key organism to resolve the obscurity of the origin and early evolution of photosynthesis. Cfl. aurantiacus contains a chimeric photosystem that comprises some characters of green sulfur bacteria and purple photosynthetic bacteria, and also has some unique electron transport proteins compared to other photosynthetic bacteria. Methods The complete genomic sequence of Cfl. aurantiacus has been determined, analyzed and compared to the genomes of other photosynthetic bacteria. Results Abundant genomic evidence suggests that there have been numerous gene adaptations/replacements in Cfl. aurantiacus to facilitate life under both anaerobic and aerobic conditions, including duplicate genes and gene clusters for the alternative complex III (ACIII, auracyanin and NADH:quinone oxidoreductase; and several aerobic/anaerobic enzyme pairs in central carbon metabolism and tetrapyrroles and nucleic acids biosynthesis. Overall, genomic information is consistent with a high tolerance for oxygen that has been reported in the growth of Cfl. aurantiacus. Genes for the chimeric photosystem, photosynthetic electron transport chain, the 3-hydroxypropionate autotrophic carbon fixation cycle, CO2-anaplerotic pathways, glyoxylate cycle, and sulfur reduction pathway are present. The central carbon metabolism and sulfur assimilation pathways in Cfl. aurantiacus are discussed. Some features of the Cfl. aurantiacus genome are compared with those of the Roseiflexus castenholzii genome. Roseiflexus castenholzii is a recently characterized FAP bacterium and phylogenetically closely related to Cfl

  2. Sphaerotilus natans, a neutrophilic iron-related filamentous bacterium : mechanisms of uranium scavenging

    International Nuclear Information System (INIS)

    Heavy metals and radionuclides are present in some ecosystems worldwide due to natural contaminations or anthropogenic activities. The use of microorganisms to restore those polluted ecosystems, a process known as bioremediation, is of increasing interest, especially under near-neutral pH conditions. Iron minerals encrusting neutrophilic iron-related bacteria, especially Bacterio-genic Iron Oxides (BIOS), have a poorly crystalline structure, which in addition to their large surface area and reactivity make them excellent scavengers for inorganic pollutants. In this PhD work we studied the different mechanisms of uranium scavenging by the neutrophilic bacterium Sphaerotilus natans, chosen as a model bacterium for iron-related sheath-forming filamentous microorganisms. S. natans can grow as single cells and filaments. The latter were used to investigate U(VI) bio-sorption and U(VI) sorption onto BIOS. In addition, uranium sorption onto the abiotic analogues of such iron minerals was assessed. In order to use S. natans filaments for U(VI) scavenging, it was necessary to identify factors inducing S. natans filamentation. The influence of oxygen was ascertained by using molecular biology techniques and our results revealed that while saturated oxygen conditions resulted in single cell growth, a moderate oxygen depletion to ∼ 3 mg O2.L-1 led to the desired filamentous growth of S. natans. BIOS attached to S. natans filaments as well as the abiotic analogues were analysed by XAS at Fe K-edge. Both materials were identified as amorphous iron(III) phosphates with a small component of Fe(II), with a high reactivity towards scavenging of inorganic pollutants. In addition, EXAFS at the U LIII-edge revealed a common structure for the O shells, while those for P, Fe and C were different for each sorbent. An integrated approach combining experimental techniques and speciation calculations made it possible to describe U(VI) adsorption isotherms by using a surface complexation

  3. A Novel Treatment Protects Chlorella at Commercial Scale from the Predatory Bacterium Vampirovibrio chlorellavorus

    Science.gov (United States)

    Ganuza, Eneko; Sellers, Charles E.; Bennett, Braden W.; Lyons, Eric M.; Carney, Laura T.

    2016-01-01

    The predatory bacterium, Vampirovibrio chlorellavorus, can destroy a Chlorella culture in just a few days, rendering an otherwise robust algal crop into a discolored suspension of empty cell walls. Chlorella is used as a benchmark for open pond cultivation due to its fast growth. In nature, V. chlorellavorus plays an ecological role by controlling this widespread terrestrial and freshwater microalga, but it can have a devastating effect when it attacks large commercial ponds. We discovered that V. chlorellavorus was associated with the collapse of four pilot commercial-scale (130,000 L volume) open-pond reactors. Routine microscopy revealed the distinctive pattern of V. chlorellavorus attachment to the algal cells, followed by algal cell clumping, culture discoloration and ultimately, growth decline. The “crash” of the algal culture coincided with increasing proportions of 16s rRNA sequencing reads assigned to V. chlorellavorus. We designed a qPCR assay to predict an impending culture crash and developed a novel treatment to control the bacterium. We found that (1) Chlorella growth was not affected by a 15 min exposure to pH 3.5 in the presence of 0.5 g/L acetate, when titrated with hydrochloric acid and (2) this treatment had a bactericidal effect on the culture (2-log decrease in aerobic counts). Therefore, when qPCR results indicated a rise in V. chlorellavorus amplicons, we found that the pH-shock treatment prevented the culture crash and doubled the productive longevity of the culture. Furthermore, the treatment could be repeatedly applied to the same culture, at the beginning of at least two sequential batch cycles. In this case, the treatment was applied preventively, further increasing the longevity of the open pond culture. In summary, the treatment reversed the infection of V. chlorellavorus as confirmed by observations of bacterial attachment to Chlorella cells and by detection of V. chlorellavorus by 16s rRNA sequencing and qPCR assay. The p

  4. Draft genome sequence of Bacillus okhensis Kh10-101T, a halo-alkali tolerant bacterium from Indian saltpan

    Directory of Open Access Journals (Sweden)

    Pilla Sankara Krishna

    2015-12-01

    Full Text Available We report the 4.86-Mb draft genome sequence of Bacillus okhensis strain Kh10-101T, a halo-alkali tolerant rod shaped bacterium isolated from a salt pan near port of Okha, India. This bacterium is a potential model to study the molecular response of bacteria to salt as well as alkaline stress, as it thrives under both high salt and high pH conditions. The draft genome consist of 4,865,284 bp with 38.2% G + C, 4952 predicted CDS, 157 tRNAs and 8 rRNAs. Sequence was deposited at DDBJ/EMBL/GenBank under the project accession JRJU00000000.

  5. Isolation and characterization of Bacillus subtilis EB-28, an endophytic bacterium strain displaying biocontrol activity against Botrytis cinerea Pers

    Institute of Scientific and Technical Information of China (English)

    Shutong WANG; Tongle HU; Yanling JIAO; Jianjian WEI; Keqiang CAO

    2009-01-01

    The fungal pathogen Botrytis cinerea Pers. causes severe rotting on tomato fruits during storage and shelf life. As a biological control agent, endophytic bacterium was regarded as an effective alternative to chemical control. Out of 238 endophytic bacterial isolates, three strains (EB-15, EB-28, and EB-122) isolated from Lycopersicum esculentum Mill., Speranskia tuberculata (Bge.) Baill, and Dictamnus dasycarpus Turcz. respectively were found to be strongly antagonistic to the pathogen in vitro and were selected for further in vivo tests. One endophytic bacterium strain, encoded EB-28, was selected from the three in vivo tested isolates. The inhibitive rate of EB-28 reached 71.1% in vitro and 52.4% in vivo. EB-28 was identified as Bacillus subtilis according to its morphological, physiological, and biochemical characteristics and 16S rDNA sequence analysis.

  6. Microbial selenite reduction with organic carbon and electrode as sole electron donor by a bacterium isolated from domestic wastewater.

    Science.gov (United States)

    Nguyen, Van Khanh; Park, Younghyun; Yu, Jaecheul; Lee, Taeho

    2016-07-01

    Selenium is said to be multifaceted element because it is essential at a low concentration but very toxic at an elevated level. For the purpose of screening a potential microorganism for selenite bioremediation, we isolated a bacterium, named strain THL1, which could perform both heterotrophic selenite reduction, using organic carbons such as acetate, lactate, propionate, and butyrate as electron donors under microaerobic condition, and electrotrophic selenite reduction, using an electrode polarized at -0.3V (vs. standard hydrogen electrode) as the sole electron donor under anaerobic condition. This bacterium determined to be a new strain of the genus Cronobacter, could remove selenite with an efficiency of up to 100%. This study is the first demonstration on a pure culture could take up electrons from an electrode to perform selenite reduction. The selenium nanoparticles produced by microbial selenite reduction might be considered for recovery and use in the nanotechnology industry. PMID:27099943

  7. Abscesses associated with a Brucella inopinata-like bacterium in a big-eyed tree frog (Leptopelis vermiculatus).

    Science.gov (United States)

    Fischer, Dominik; Lorenz, Nadja; Heuser, Wenke; Kämpfer, Peter; Scholz, Holger C; Lierz, Michael

    2012-09-01

    A 4-yr-old big-eyed tree frog (Leptopelis vermiculatus) was submitted with two pea-sized (4-mm diameter), firm, and painful masses on the right side of its back. The two abscess-like masses were surgically opened, and a whitish-yellow pasty content was removed. A Brucella inopinata-like bacterium was obtained in pure culture and was resistant against ampicillin and tylosin but sensitive to the 8 other antibiotics tested. The organism was identified by polymerase chain reaction and sequencing of the 16S ribosomal ribonucleic acid (acc. no. HE608873) and recA (acc. no. HE608874) genes after preliminary misidentification as Ochrobactrum anthropi when using a commercial identification system. To the authors' knowledge, a B. inopinata-like bacterium has not been reported previously in amphibians. The organism is a potential human pathogen and may present a risk for people handling amphibians. PMID:23082529

  8. Complete genome sequence of the complex carbohydrate-degrading marine bacterium, Saccharophagus degradans strain 2-40 T.

    Directory of Open Access Journals (Sweden)

    Ronald M Weiner

    2008-05-01

    Full Text Available The marine bacterium Saccharophagus degradans strain 2-40 (Sde 2-40 is emerging as a vanguard of a recently discovered group of marine and estuarine bacteria that recycles complex polysaccharides. We report its complete genome sequence, analysis of which identifies an unusually large number of enzymes that degrade >10 complex polysaccharides. Not only is this an extraordinary range of catabolic capability, many of the enzymes exhibit unusual architecture including novel combinations of catalytic and substrate-binding modules. We hypothesize that many of these features are adaptations that facilitate depolymerization of complex polysaccharides in the marine environment. This is the first sequenced genome of a marine bacterium that can degrade plant cell walls, an important component of the carbon cycle that is not well-characterized in the marine environment.

  9. Isolation and characterization of endophytic bacterium LRE07 from cadmium hyperaccumulator Solanum nigrum L. and its potential for remediation.

    Science.gov (United States)

    Luo, Shenglian; Wan, Yong; Xiao, Xiao; Guo, Hanjun; Chen, Liang; Xi, Qiang; Zeng, Guangming; Liu, Chengbin; Chen, Jueliang

    2011-03-01

    Valuable endophytic strains facilitating plants growth and detoxification of heavy metals are required because the application of plant-endophyte symbiotic system is a promising potential technique to improve efficiency of phytoremediation. In this study, endophytic bacterium LRE07 was isolated from cadmium hyperaccumulator Solanum nigrum L. It was identified as Serratia sp. by 16S rRNA sequence analysis. The endophytic bacterium LRE07 was resistant to the toxic effects of heavy metals, solubilized mineral phosphate, and produced indoleacetic acid and siderophore. The heavy metal detoxification was studied in growing LRE07 cells. The strain bound over 65% of cadmium and 35% of zinc in its growing cells from single metal solutions 72 h after inoculation. Besides the high removal efficiencies in single-ion system, an analogous removal phenomenon was also observed in multi-ions system, indicating that the endophyte possesses specific and remarkable heavy metal remediation abilities. PMID:20953602

  10. Interaction between the bacterium Pseudomonas fluorescens and vermiculite: Effects on chemical, mineralogical, and mechanical properties of vermiculite

    Science.gov (United States)

    Müller, Barbara; DéFago, GenèVieve

    2006-06-01

    On an expanded and crushed vermiculite, changes in chemical, mineralogical, and rheological properties of the mineral affected by microbial activity were investigated. Determination of the water content, grain size, X-ray diffraction pattern, intercrystalline swelling with glycerol, layer charge, CEC, exchangeable cations, BET surface, and rheology provided the necessary information about the differences between pure vermiculite, vermiculite suspensions containing the nutrient medium, and vermiculite suspensions containing the nutrient medium and the bacterium Pseudomonas fluorescens strain CHA0. The aerobic bacterium Pseudomonas fluorescens causes a decrease in grain size, aggregation of vermiculite grains as evidenced by smaller BET surfaces, and enhanced viscosity of the bacteria containing slurries. Layer charge, intercrystalline swelling, and CEC were not affected by the microbial activity, nor did the bacteria count for the exchange of potassium and magnesium against sodium in the vermiculite. The microbes inhibited this exchange process during the first stage of the experiments; however, increasing run time favors the exchange as well.

  11. DNA cloning, characterization, and inhibition studies of an α-carbonic anhydrase from the pathogenic bacterium Vibrio cholerae.

    Science.gov (United States)

    Del Prete, Sonia; Isik, Semra; Vullo, Daniela; De Luca, Viviana; Carginale, Vincenzo; Scozzafava, Andrea; Supuran, Claudiu T; Capasso, Clemente

    2012-12-13

    We have cloned, purified, and characterized an α-carbonic anhydrase (CA, EC 4.2.1.1) from the human pathogenic bacterium Vibrio cholerae, VchCA. The new enzyme has significant catalytic activity, and an inhibition study with sulfonamides and sulfamates led to the detection of a large number of low nanomolar inhibitors, among which are methazolamide, acetazolamide, ethoxzolamide, dorzolamide, brinzolamide, benzolamide, and indisulam (KI values in the range 0.69-8.1 nM). As bicarbonate is a virulence factor of this bacterium and since ethoxzolamide was shown to inhibit the in vivo virulence, we propose that VchCA may be a target for antibiotic development, exploiting a mechanism of action rarely considered until now. PMID:23181552

  12. Lysing activity of an indigenous algicidal bacterium Aeromonas sp. against Microcystis spp. isolated from Lake Taihu.

    Science.gov (United States)

    Yang, Fei; Li, Xiaoqin; Li, Yunhui; Wei, Haiyan; Yu, Guang; Yin, Lihong; Liang, Geyu; Pu, Yuepu

    2013-01-01

    This study aimed to isolate and characterize an indigenous algicidal bacterium named LTH-1 and its algae-lysing compounds active against three Microcystis aeruginosa strains (toxic TH1, nontoxic TH2 and standard FACHB 905). The LTH-1 isolated from Lake Taihu, near Wuxi City in China, was identified as Aeromonas sp. based on its morphological characteristic features and phylogenetic analysis by sequencing of 16S rDNA. Extracellular compounds produced by LTH-1 showed strong algaelysing activity, and they were water-soluble and heat-tolerant, with a molecular mass lower than 2 kDa. Two algae-lysing compounds were isolated and purified from extracellular filtrate using silica gel column chromatography. One of these was identified as phenylalanine (C9H11NO2, m/z 166.0862) and the other (C8H16N2O3, m/z 189.1232) was unidentified by hybrid ion trap/time-of-flight mass spectrometry coupled with a high-performance liquid chromatography (LC/MS-IT-TOF) system. The half maximal effective concentration (EC50) of phenylalanine produced by LTH-1 against FACHB 905 was 68.2 +/- 8.2 microg mL(-1) in 48h. These results suggest that the algicidal Aeromonas sp. LTH-1 could play a role in controlling Microcystis blooms, and its extracellular compounds are also potentially useful for regulating blooms of the harmful M. aeruginosa. PMID:24191475

  13. A simple assay for determining activities of phosphopentomutase from a hyperthermophilic bacterium Thermotoga maritima.

    Science.gov (United States)

    Moustafa, Hanan M A; Zaghloul, Taha I; Zhang, Y-H Percival

    2016-05-15

    Phosphopentomutase (PPM) catalyzes the interconversion of α-D-(deoxy)-ribose 1-phosphate and α-D-(deoxy)-ribose 5-phosphate. We developed a coupled or uncoupled enzymatic assay with an enzyme nucleoside phosphorylase for determining PPM activities on D-ribose 5-phosphate at a broad temperature range from 30 to 90 °C. This assay not only is simple and highly sensitive but also does not require any costly special instrument. Via this technology, an open reading frame TM0167 from a thermophilic bacterium Thermotoga maritima putatively encoding PPM was cloned. The recombinant PPM was overexpressed in Escherichia coli Rosetta. This enzyme has the highest activity at 90 °C. MnCl2 (0.1 mM) and 50 μM α-D-glucose 1,6-bisphosphate are cofactors. The kinetic parameters of Km and kcat are 1.2 mM and 185 s(-1) at 90 °C, respectively. The enzyme has a half-life time of up to 156 min at 90 °C. This enzyme is the most active and thermostable PPM reported to date. PMID:26924489

  14. Two New Xylanases with Different Substrate Specificities from the Human Gut Bacterium Bacteroides intestinalis DSM 17393

    KAUST Repository

    Hong, Pei-Ying

    2014-01-24

    Xylan is an abundant plant cell wall polysaccharide and is a dominant component of dietary fiber. Bacteria in the distal human gastrointestinal tract produce xylanase enzymes to initiate the degradation of this complex heteropolymer. These xylanases typically derive from glycoside hydrolase (GH) families 10 and 11; however, analysis of the genome sequence of the xylan-degrading human gut bacterium Bacteroides intestinalis DSM 17393 revealed the presence of two putative GH8 xylanases. In the current study, we demonstrate that the two genes encode enzymes that differ in activity. The xyn8A gene encodes an endoxylanase (Xyn8A), and rex8A encodes a reducing-end xylose-releasing exo-oligoxylanase (Rex8A). Xyn8A hydrolyzed both xylopentaose (X5) and xylohexaose (X6) to a mixture of xylobiose (X2) and xylotriose (X3), while Rex8A hydrolyzed X3 through X6 to a mixture of xylose (X1) and X2. Moreover, rex8A is located downstream of a GH3 gene (xyl3A) that was demonstrated to exhibit β-xylosidase activity and would be able to further hydrolyze X2 to X1. Mutational analyses of putative active site residues of both Xyn8A and Rex8A confirm their importance in catalysis by these enzymes. Recent genome sequences of gut bacteria reveal an increase in GH8 Rex enzymes, especially among the Bacteroidetes, indicating that these genes contribute to xylan utilization in the human gut.

  15. Roles of Thioredoxins in the Obligate Anaerobic Green Sulfur Photosynthetic Bacterium Chlorobaculum tepidum

    Institute of Scientific and Technical Information of China (English)

    Naomi Hosoya-Matsuda; Kazuhito Inoue; Toru Hisabori

    2009-01-01

    Thioredoxin is a small ubiquitous protein that is involved in the dithiol-disulfide exchange reaction, by way of two cysteine residues located on the molecule surface. In order to elucidate the role of thioredoxin in Chlorobaculum tepidum, an anaerobic green sulfur bacterium that uses various inorganic sulfur compounds and H2S as electron donors under strict anaerobic conditions for growth, we applied the thioredoxin affinity chromatography method (Motohashi et al., 2001). In this study, 37 cytoplasmic proteins were captured as thioredoxin target candidates, including proteins involved in sulfur assimilation. Furthermore, six of the candidate proteins were members of the reductive tricarboxylic acid cycle (pyruvate orthophosphate dikinase, pyruvate flavodoxin/ferredoxin oxidoreductase, α-oxoglutarate synthase, citrate lyase, citrate synthase, malate dehydrogenase). The redox sensitivity of three enzymes was then examined: citrate lyase, citrate synthase, and malate dehydrogenase, using their recombinant proteins. Based on the information relating to the target proteins, the significance of thioredoxin as a reductant for the metabolic pathway in the anaerobic photosyn-thetic bacteria is discussed.

  16. Synergism between gamma and ultrasonic irradiation of the bacterium E. coli. B

    International Nuclear Information System (INIS)

    Using simple and conventional culture techniques for the bacterium E.Coli.B synergism between independently lethal doses of ultrasonic and cobalt-60 gamma irradiation is established by comparing the observed surviving fractions for sequential irradiations with the values expected from independent measurements. The effects on gamma irradiation of three different preliminary doses of ultrasonic irradiation at 13 kHz, which independently yield surviving fractions of the order of 0.5, 0.05 and 0.005, are investigated by measuring at various gamma ray surviving fractions, down to 0.001, the relative sensitivity of sonicated and non-sonicated samples. The results of these investigations indicate two things: pre-sonicated samples are relatively more sensitive than non-treated samples by a factor which increases with the magnitude of the ultrasonic dose; the relative sensitivity of samples with identical presonication doses decreases with increasing gamma ray dose, ie in simple terms a shouldered survival curve becomes less shouldered following presonication. Gamma ray dosimetry was performed by the Fricke method and ultrasonic dosimetry by measuring the initial rate of increase in temperature. This thermometric method of ultrasonic dosimetry also permitted an investigation into the temperature behavior of the samples during sonication and from these measurements the authors deduce that the observed synergism cannot be explained in terms of the heating effect reported to be of critical importance in previously observed synergism between non-lethal ultrasonic doses and X-rays

  17. Sulfonamide inhibition studies of the β-carbonic anhydrase from the pathogenic bacterium Vibrio cholerae.

    Science.gov (United States)

    Del Prete, Sonia; Vullo, Daniela; De Luca, Viviana; Carginale, Vincenzo; Ferraroni, Marta; Osman, Sameh M; AlOthman, Zeid; Supuran, Claudiu T; Capasso, Clemente

    2016-03-01

    The genome of the pathogenic bacterium Vibrio cholerae encodes for three carbonic anhydrases (CAs, EC 4.2.1.1) belonging to the α-, β- and γ-classes. VchCA, the α-CA from this species was investigated earlier, whereas the β-class enzyme, VchCAβ was recently cloned, characterized kinetically and its X-ray crystal structure reported by this group. Here we report an inhibition study with sulfonamides and one sulfamate of this enzyme. The best VchCAβ inhibitors were deacetylated acetazolamide and methazolamide and hydrochlorothiazide, which showed inhibition constants of 68.2-87.0nM. Other compounds, with medium potency against VchCAβ, (KIs in the range of 275-463nM), were sulfanilamide, metanilamide, sulthiame and saccharin whereas the clinically used agents such as acetazolamide, methazolamide, ethoxzolamide, dorzolamide, zonisamide and celecoxib were micromolar inhibitors (KIs in the range of 4.51-8.57μM). Identification of potent and possibly selective inhibitors of VchCA and VchCAβ over the human CA isoforms, may lead to pharmacological tools useful for understanding the physiological role(s) of this under-investigated enzymes. PMID:26850377

  18. Anion inhibition studies of the β-carbonic anhydrase from the pathogenic bacterium Vibrio cholerae.

    Science.gov (United States)

    Vullo, Daniela; Del Prete, Sonia; De Luca, Viviana; Carginale, Vincenzo; Ferraroni, Marta; Dedeoglu, Nurcan; Osman, Sameh M; AlOthman, Zeid; Capasso, Clemente; Supuran, Claudiu T

    2016-03-01

    The genome of the pathogenic bacterium Vibrio cholerae encodes for three carbonic anhydrases (CAs, EC 4.2.1.1) belonging to the α-, β- and γ-classes. Here we report and anion inhibition study of the β-CA, VchCAβ with anions and other small molecules which inhibit metalloenzymes. The best VchCAβ anion inhibitors were sulfamide, sulfamate, phenylboronic acid and phenylarsonic acid, which showed KIs in the range of 54-86μM. Diethyldithiocarbonate was also an effective VchCAβ inhibitor, with an inhibition constant of 0.73mM. The halides, cyanate, thiocyanate, cyanide, bicarbonate, carbonate, nitrate, nitrite, stannate, selenate, tellurate, divanadate, tetraborate, perrhenate, perruthenate, peroxydisulfate, selenocyanide, trithiocarbonate, and fluorosulfonate showed affinity in the low millimolar range, with KIs of 2.3-9.5mM. Identification of selective inhibitors of VchCAβ (over the human CA isoforms) may lead to pharmacological tools useful for understanding the physiological role(s) of this under-investigated enzyme. PMID:26853167

  19. Isolation and characterization of a marine bacterium producing protease from Chukchi Sea, Arctic

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A Gram negative bacterium Ar/W/b/75°25'N/1 producing extracellular alkaline protease was isolated from surface water of latitude 75°25'N, and longitude 162°25'W in Chukchi sea, Arctic. The strain can grow at the temperature range from 7℃ to 30℃, and grow better at 30(℃. It can not grow at 40℃. Keeping certain salinity concentration in medium is necessary for cell growth. It grows well in medium containing salinity concentration from 0. 5 % to 10 % sodium chloride. Glucose, sucrose and soluble starch can be utilized by the strain, among which glucose is the optimal carbon source. Peptone is the optimal organic nitrogen source for cell growth and protease producing, and ammonium nitrate is the optimal inorganic nitrogen source.About 75.7% of total protease of the strain are extracellular enzyme. Optimal temperature for proteolytic activity is at 40℃. Protease of the strain keeps stable below 40℃, and shows high proteolytic activity within the pH range from 7 to 11.

  20. Purification and Characterization of Catalase from Marine Bacterium Acinetobacter sp. YS0810

    Directory of Open Access Journals (Sweden)

    Xinhua Fu

    2014-01-01

    Full Text Available The catalase from marine bacterium Acinetobacter sp. YS0810 (YS0810CAT was purified and characterized. Consecutive steps were used to achieve the purified enzyme as follows: ethanol precipitation, DEAE Sepharose ion exchange, Superdex 200 gel filtration, and Resource Q ion exchange. The active enzyme consisted of four identical subunits of 57.256 kDa. It showed a Soret peak at 405 nm, indicating the presence of iron protoporphyrin IX. The catalase was not apparently reduced by sodium dithionite but was inhibited by 3-amino-1,2,4-triazole, hydroxylamine hydrochloride, and sodium azide. Peroxidase-like activity was not found with the substrate o-phenylenediamine. So the catalase was determined to be a monofunctional catalase. N-terminal amino acid of the catalase analysis gave the sequence SQDPKKCPVTHLTTE, which showed high degree of homology with those of known catalases from bacteria. The analysis of amino acid sequence of the purified catalase by matrix-assisted laser desorption ionization time-of-flight mass spectrometry showed that it was a new catalase, in spite of its high homology with those of known catalases from other bacteria. The catalase showed high alkali stability and thermostability.

  1. Sodium-driven energy conversion for flagellar rotation of the earliest divergent hyperthermophilic bacterium.

    Science.gov (United States)

    Takekawa, Norihiro; Nishiyama, Masayoshi; Kaneseki, Tsuyoshi; Kanai, Tamotsu; Atomi, Haruyuki; Kojima, Seiji; Homma, Michio

    2015-01-01

    Aquifex aeolicus is a hyperthermophilic, hydrogen-oxidizing and carbon-fixing bacterium that can grow at temperatures up to 95 °C. A. aeolicus has an almost complete set of flagellar genes that are conserved in bacteria. Here we observed that A. aeolicus has polar flagellum and can swim with a speed of 90 μm s(-1) at 85 °C. We expressed the A. aeolicus mot genes (motA and motB), which encode the torque generating stator proteins of the flagellar motor, in a corresponding mot nonmotile mutant of Escherichia coli. Its motility was slightly recovered by expression of A. aeolicus MotA and chimeric MotB whose periplasmic region was replaced with that of E. coli. A point mutation in the A. aeolicus MotA cytoplasmic region remarkably enhanced the motility. Using this system in E. coli, we demonstrate that the A. aeolicus motor is driven by Na(+). As motor proteins from hyperthermophilic bacteria represent the earliest motor proteins in evolution, this study strongly suggests that ancient bacteria used Na(+) for energy coupling of the flagellar motor. The Na(+)-driven flagellar genes might have been laterally transferred from early-branched bacteria into late-branched bacteria and the interaction surfaces of the stator and rotor seem not to change in evolution. PMID:26244427

  2. Applicability of recombinant β-xylosidase from the extremely thermophilic bacterium Geobacillus thermodenitrificans in synthesizing alkylxylosides.

    Science.gov (United States)

    Jain, Ira; Kumar, Vikash; Satyanarayana, T

    2014-10-01

    The β-xylosidase encoding gene (XsidB) of the extremely thermophilic bacterium Geobacillus thermodenitrificans has been cloned and expressed in Escherichia coli. The homotrimeric recombinant XsidB is of 204.0kDa, which is optimally active at 60°C and pH 7.0 with T1/2 of 58min at 70°C. The β-xylosidase remains unaffected in the presence of most metal ions and organic solvents. The Km [p-nitrophenyl β-xyloside (pNPX)], Vmax and kcat values of the enzyme are 2×10(-3)M, 1250μmolesmg(-1)min(-1) and 13.20×10(5)min(-1), respectively. The enzyme catalyzes transxylosylation reactions in the presence of alcohols as acceptors. The pharmaceutically important β-methyl-d-xylosides could be produced using pNPX as the donor and methanol as acceptor. The products of transxylosylation were identified by TLC and HPLC, and the structure was confirmed by (1)H NMR analysis. The enzyme is also useful in synthesizing transxylosylation products from the wheat bran hydrolysate.

  3. A pseudokinase couples signaling pathways to enable asymmetric cell division in a bacterium

    Directory of Open Access Journals (Sweden)

    W. Seth Childers

    2014-12-01

    Full Text Available Bacteria face complex decisions when initiating developmental events such as sporulation, nodulation, virulence, and asymmetric cell division. These developmental decisions require global changes in genomic readout, and bacteria typically employ intricate (yet poorly understood signaling networks that enable changes in cell function. The bacterium Caulobacter crescentus divides asymmetrically to yield two functionally distinct cells: a motile, chemotactic swarmer cell, and a sessile stalked cell with replication and division capabilities. Work from several Caulobacter labs has revealed that differentiation requires concerted regulation by several two-component system (TCS signaling pathways that are differentially positioned at the poles of the predivisional cell (Figure 1. The strict unidirectional flow from histidine kinase (HK to the response regulator (RR, observed in most studied TCS, is difficult to reconcile with the notion that information can be transmitted between two or more TCS signaling pathways. In this study, we uncovered a mechanism by which daughter cell fate, which is specified by the DivJ-DivK-PleC system and effectively encoded in the phosphorylation state of the single-domain RR DivK, is communicated to the CckA-ChpT-CtrA signaling pathway that regulates more than 100 genes for polar differentiation, replication initiation and cell division. Using structural biology and biochemical findings we proposed a mechanistic basis for TCS pathway coupling in which the DivL pseudokinase is repurposed as a sensor rather than participant in phosphotransduction.

  4. Molecular cloning and characterization of a new peptide deformylase from human pathogenic bacterium Helicobacter pylori

    International Nuclear Information System (INIS)

    Helicobacter pylori is a gram-negative pathogenic bacterium, which is associated with peptic ulcer disease and gastric cancer. It is urgent to discover novel drug targets for appropriate antimicrobial agents against this human pathogen. In bacteria, peptide deformylase (PDF) catalyzes the removal of a formyl group from the N-termini of nascent polypeptides. Due to its essentiality and absence in mammalian cells, PDF has been considered as an attractive target for the discovery of novel antibiotics. In this work, a new PDF gene (def) from H. pylori strain SS1 was cloned, expressed, and purified in Escherichia coli system. Sequence alignment shows that H. pylori PDF (HpPDF) shares about 40% identity to E. coli PDF (EcPDF). The enzymatic properties of HpPDF demonstrate its relatively high activity toward formyl-Met-Ala-Ser, with Kcat of 3.4 s-1, Km of 1.7 mM, and Kcat/Km of 2000 M-1 s-1. HpPDF enzyme appears to be fully active at pH between 8.0 and 9.0, and temperature 50 deg. C. The enzyme activity of Co2+-containing HpPDF is apparently higher than that of Zn2+-containing HpPDF. This present work thereby supplies a potential platform that facilitates the discovery of novel HpPDF inhibitors and further of possible antimicrobial agents against H. pylori

  5. Remediation of contaminated subsurface materials by a metal-reducing bacterium

    Energy Technology Data Exchange (ETDEWEB)

    Gorby, Y.A.; Amonette, J.E.; Fruchter, J.S.

    1994-11-01

    A biotic approach for remediating subsurface sediments and groundwater contaminated with carbon tetrachloride (CT) and chromium was evaluated. Cells of the Fe(iii)-reducing bacterium strain BrY were added to sealed, anoxic flasks containing Hanford groundwater, natural subsurface sediments, and either carbon tetrachloride, CT, or oxidized chromium, Cr(VI). With lactate as the electron donor, BrY transformed CT to chloroform (CF), which accumulated to about 1 0 % of the initial concentration of CT. The remainder of the CT was transformed to unidentified, nonvolatile compounds. Transformation of CT by BrY was an indirect process Cells reduced solid phase Fe(ill) to chemically reactive FE(II) that chemically transformed the chlorinated contaminant. Cr(VI), in contrast, was reduced by a direct enzymatic reaction in the presence or absence of Fe(III)-bearing sediments. These results demonstrate that Fe(ill)-reducing bacteria provide potential for transforming CT and for reducing CR(VI) to less toxic Cr(III). Technologies for stimulating indigenous populations of metal-reducing bacteria or for introducing specific metal-reducing bacteria to the subsurface are being investigated.

  6. Optimization, purification, and characterization of L-asparaginase from Actinomycetales bacterium BkSoiiA.

    Science.gov (United States)

    Dash, Chitrangada; Mohapatra, Sukanti Bala; Maiti, Prasanta Kumar

    2016-01-01

    Actinobacteria are promising source of a wide range of important enzymes, some of which are produced in industrial scale, with others yet to be harnessed. L-Asparaginase is used as an antineoplastic agent. The present work deals with the production and optimization of L-asparaginase from Actinomycetales bacterium BkSoiiA using submerged fermentation in M9 medium. Production optimization resulted in a modified M9 medium with yeast extract and fructose as carbon and nitrogen sources, respectively, at pH 8.0, incubated for 120 hr at 30 ± 2 °C. The crude enzyme was purified to near homogeneity by ammonium sulfate precipitation following dialysis, ion-exchange column chromatography, and finally gel filtration. The sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis (PAGE) revealed an apparent molecular weight of 57 kD. The enzyme was purified 95.06-fold and showed a final specific activity of 204.37 U/mg with 3.49% yield. The purified enzyme showed maximum activity at a pH 10.0 and was stable at pH 7.0 to 9.0. The enzyme was activated by Mn(2+) and strongly inhibited by Ba(2+). All these preliminary characterization suggests that the L-asparaginase from the source may be a tool useful to pharmaceutical industries after further research.

  7. Selective Capture of Transcribed Sequences: A Promising Approach for Investigating Bacterium-Insect Interactions

    Directory of Open Access Journals (Sweden)

    Ruisheng An

    2012-03-01

    Full Text Available Bacterial interactions with eukaryotic hosts are complex processes which vary from pathogenic to mutualistic. Identification of bacterial genes differentially expressed in the host, promises to unravel molecular mechanisms driving and maintaining such interactions. Several techniques have been developed in the past 20 years to investigate bacterial gene expression within their hosts. The most commonly used techniques include in-vivo expression technology, signature-tagged mutagenesis, differential fluorescence induction, and cDNA microarrays. However, the limitations of these techniques in analyzing bacterial in-vivo gene expression indicate the need to develop alternative tools. With many advantages over the other methods for analyzing bacterial in-vivo gene expression, selective capture of transcribed sequences (SCOTS technique has the prospect of becoming an elegant tool for discovery of genes involved in the bacterium-host interaction. Here, we summarize the advances in SCOTS technique, including its current and potential applications in bacterial gene expression studies under a variety of conditions from in-vitro to in-vivo and from mammals to insects.

  8. Free-living freshwater amoebae differ in their susceptibility to the pathogenic bacterium Legionella pneumophila.

    Science.gov (United States)

    Dey, Rafik; Bodennec, Jacques; Mameri, Mouh Oulhadj; Pernin, Pierre

    2009-01-01

    Legionella pneumophila is known as a facultative intracellular parasite of free-living soil and freshwater amoebae, of which several species have been shown to support the growth of the pathogenic bacteria. We report for the first time the behaviour of two strains (c2c and Z503) of the amoeba Willaertia magna towards different strains of L. pneumophila serogroup 1 and compared it with Acanthamoeba castellanii and Hartmannella vermiformis, known to be L. pneumophila permissive. In contrast to the results seen with other amoebae, W. magna c2c inhibited the growth of one strain of Legionella (L. pneumophila, Paris), but not of others belonging to the same serogroup (L. pneumophila, Philadelphia and L. pneumophila, Lens). Also, the different L. pneumophila inhibited cell growth and induced cell death in A. castellanii, H. vermiformis and W. magna Z503 within 3-4 days while W. magna c2c strain remained unaffected even up to 7 days. Electron microscopy demonstrated that the formation of numerous replicative phagosomes observed within Acanthamoeba and Hartmannella is rarely seen in W. magna c2c cocultured with L. pneumophila. Moreover, the morphological differences were observed between L. pneumophila cultured either with Willaertia or other amoebae. These observations show that amoebae are not all equally permissive to L. pneumophila and highlight W. magna c2c as particularly resistant towards some strains of this bacterium.

  9. Cold stress promoting a psychrotolerant bacterium Pseudomonas fragi P121 producing trehaloase.

    Science.gov (United States)

    Mei, Yan-Zhen; Huang, Peng-Wei; Liu, Yang; He, Wei; Fang, Wen-Wan

    2016-08-01

    A newly isolated Pseudomonas fragi P121 strain in a soil sample taken from the Arctic Circle is able to produce trehalose. The P121 strain was able to grow at temperatures ranging from 4 to 25 °C, had an optimum pH of 6.5, and an optimum salt concentration of 2 %. The P121 strain had a survival rate of 29.1 % after being repeatedly frozen and thawed five times, and a survival rate of 78.9 % when placed in physiological saline for 15 days at 20 °C after cold shock, which is far higher than the type strain Pseudomonas fragi ATCC 4973. The P121 strain could produce 2.89 g/L trehalose, which was 18.6 % of dry cell weight within 52 h in a 25 L fermention tank using the malt extract prepared from barley as medium at 15 °C, while only 11.8 % of dry cell weight at 20 °C. These results suggested that cold stress promoted the strain producing trehalose. It is the first reported cold-tolerant bacterium that produces trehalose, which may protect cells against the cold environment. PMID:27339315

  10. Screening and optimization of EPA-producing antarctic psychrophilic bacterium Shewanella sp.NJ136

    Institute of Scientific and Technical Information of China (English)

    Zhang Botao; Miao Jinlai; Ma Jinhai; Zheng Zhou; Wang Guodong; Wang Quanfu; Li Guangyou; Liu Wanshun

    2007-01-01

    Two hundred strains of bacteria from Antarctic sea ice were collected and screened for their ability of producing eicosapentaenoic acid(EPA, 20:5ω3)by means of Gas Chromatography/Mass Spetrometry (GC/MS). Eight strains of bacteria containing EPA were investigated, among which the outstanding one was recorded as NJl36. This bacterium was identified as Shewanella by the biochemical characteristics and 16S rRNA sequence. Response surface methodology(RSM)was applied to optimize the medium ingredients. A 24full factorial central composite design(FFCCD)was employed to determine the maximum EPA production at optimum levels of pH, NaCl, glucose and yeast extract. The predicted optimal combination of media constituents for maximum 14.02 mg/g(about 1.7-fold increase)EPA production were determined as 30.15‰(m/v)NaCl, 9.98g/L glucose, 4.42g/L yeast extract and pH 6.08. The actual experimental results were in agreement with the prediction.

  11. Construction of the astaxanthin biosynthetic pathway in a methanotrophic bacterium Methylomonas sp. strain 16a.

    Science.gov (United States)

    Ye, Rick W; Yao, Henry; Stead, Kristen; Wang, Tao; Tao, Luan; Cheng, Qiong; Sharpe, Pamela L; Suh, Wonchul; Nagel, Eva; Arcilla, Dennis; Dragotta, Dominic; Miller, Edward S

    2007-04-01

    Methylomonas sp. strain 16a is an obligate methanotrophic bacterium that uses methane or methanol as the sole carbon source. An effort was made to engineer this organism for astaxanthin production. Upon expressing the canthaxanthin gene cluster under the control of the native hps promoter in the chromosome, canthaxanthin was produced as the main carotenoid. Further conversion to astaxanthin was carried out by expressing different combinations of crtW and crtZ genes encoding the beta-carotenoid ketolase and hydroxylase. The carotenoid intermediate profile was influenced by the copy number of these two genes under the control of the hps promoter. Expression of two copies of crtZ and one copy of crtW led to the accumulation of a large amount of the mono-ketolated product adonixanthin. On the other hand, expression of two copies of crtW and one copy of crtZ resulted in the presence of non-hydroxylated carotenoid canthaxanthin and the mono-hydroxylated adonirubin. Production of astaxanthin as the predominant carotenoid was obtained in a strain containing two complete sets of carotenoid biosynthetic genes. This strain had an astaxanthin titer ranging from 1 to 2.4 mg g(-1) of dry cell biomass depending on the growth conditions. More than 90% of the total carotenoid was astaxanthin, of which the majority was in the form of E-isomer. This result indicates that it is possible to produce astaxanthin with desirable properties in methanotrophs through genetic engineering.

  12. Role of extracellular compounds in Cd-sequestration relative to Cd uptake by bacterium Sinorhizobium meliloti

    Energy Technology Data Exchange (ETDEWEB)

    Slaveykova, Vera I., E-mail: vera.slaveykova@epfl.c [Environmental Biophysical Chemistry, IIE-ENAC, Ecole Polytechnique Federale de Lausanne (EPFL), Station 2, CH-1015 Lausanne (Switzerland); Parthasarathy, Nalini [Department of Inorganic, Analytic and Applied Chemistry, University of Geneva, Sciences II, 30 Quai Ernest Ansermet, 1211 Geneva 4 (Switzerland); Dedieu, Karine; Toescher, Denis [Environmental Biophysical Chemistry, IIE-ENAC, Ecole Polytechnique Federale de Lausanne (EPFL), Station 2, CH-1015 Lausanne (Switzerland)

    2010-08-15

    The role of bacterially derived compounds in Cd(II) complexation and uptake by bacterium Sinorhizobium meliloti wild type (WT) and genetically modified ExoY-mutant, deficient in exopolysaccharide production, was explored combining chemical speciation measurements and assays with living bacteria. Obtained results demonstrated that WT- and ExoY-strains excreted siderophores in comparable amounts, while WT-strain produced much higher amount of exopolysaccharides and less exoproteins. An evaluation of Cd(II) distribution in bacterial suspensions under short term exposure conditions, showed that most of the Cd is bound to bacterial surface envelope, including Cd bound to the cell wall and to the attached extracellular polymeric substances. However, the amount of Cd bound to the dissolved extracellular compounds increases at high Cd(II) concentrations. The implications of these findings to more general understanding of the Cd(II) fate and cycling in the environment is discussed. - Bacterial excreted extracellular compounds play minor role in Cd(II) sequestration relative to bacteria.

  13. Sulfonamide inhibition studies of the β-carbonic anhydrase from the pathogenic bacterium Vibrio cholerae.

    Science.gov (United States)

    Del Prete, Sonia; Vullo, Daniela; De Luca, Viviana; Carginale, Vincenzo; Ferraroni, Marta; Osman, Sameh M; AlOthman, Zeid; Supuran, Claudiu T; Capasso, Clemente

    2016-03-01

    The genome of the pathogenic bacterium Vibrio cholerae encodes for three carbonic anhydrases (CAs, EC 4.2.1.1) belonging to the α-, β- and γ-classes. VchCA, the α-CA from this species was investigated earlier, whereas the β-class enzyme, VchCAβ was recently cloned, characterized kinetically and its X-ray crystal structure reported by this group. Here we report an inhibition study with sulfonamides and one sulfamate of this enzyme. The best VchCAβ inhibitors were deacetylated acetazolamide and methazolamide and hydrochlorothiazide, which showed inhibition constants of 68.2-87.0nM. Other compounds, with medium potency against VchCAβ, (KIs in the range of 275-463nM), were sulfanilamide, metanilamide, sulthiame and saccharin whereas the clinically used agents such as acetazolamide, methazolamide, ethoxzolamide, dorzolamide, zonisamide and celecoxib were micromolar inhibitors (KIs in the range of 4.51-8.57μM). Identification of potent and possibly selective inhibitors of VchCA and VchCAβ over the human CA isoforms, may lead to pharmacological tools useful for understanding the physiological role(s) of this under-investigated enzymes.

  14. A Minimal Model of the E. Coli Bacterium in Exponential Phase Growth

    Science.gov (United States)

    Maitra, Arijit; Dill, Ken

    2013-03-01

    We study the fundamental process of exponential cell growth in the E. Coli bacterium under conditions of extracellular glucose limitations using a minimalistic reaction framework by accounting for energy metabolism and protein synthesis. The cell model has three nodes: ATP, the ribosomal and the non-ribosomal proteins. Their interdependencies and dynamics are wrapped in a system of ordinary differential equations. The formulations of their interactive fluxes capture the essence of cellular physiology under conditions of growth. We solve the model numerically for different glucose concentrations, and, where possible, explore the cell states analytically under steady state conditions. We verify the model predictions with available experimental data. The model lets us quantify the coupling between energy generation and biomass growth. An implication of this model is that it provides a layout to compute the fitness landscape in terms of the parameters of the cells, such as the protein translation rates, to make hypotheses about possible routes for cellular evolution under glucose limitation. Laufer Center for Phys. and Quant. Biology.

  15. Genome sequence of Enterobacter sp. ST3, a quorum sensing bacterium associated with marine dinoflagellate

    Directory of Open Access Journals (Sweden)

    Jin Zhou

    2016-03-01

    Full Text Available Phycosphere environment is a typical marine niche, harbor diverse populations of microorganisms, which are thought to play a critical role in algae host and influence mutualistic and competitive interactions. Understanding quorum sensing-based acyl-homoserine lactone (AHL language may shed light on the interaction between algal-associated microbial communities in the native environment. In this work, we isolated an epidermal bacterium (was tentatively named Enterobacter sp. ST3, and deposited in SOA China, the number is MCCC1K02277-ST3 from the marine dinoflagellate Scrippsiella trochoidea, and found it has the ability to produce short-chain AHL signal. In order to better understand its communication information at molecular level, the genomic map was investigated. The genome size was determined to be 4.81 Mb with a G + C content of 55.59%, comprising 6 scaffolds of 75 contigs containing 4647 protein-coding genes. The functional proteins were predicted, and 3534 proteins were assigned to COG functional categories. An AHL-relating gene, LuxR, was found in upstream position at contig 1. This genome data may provide clues to increase understanding of the chemical characterization and ecological behavior of strain ST3 in the phycosphere microenvironment.

  16. Augmenting Iron Accumulation in Cassava by the Beneficial Soil Bacterium Bacillus subtilis (GBO3

    Directory of Open Access Journals (Sweden)

    Monica A Freitas

    2015-08-01

    Full Text Available Cassava (Manihot esculenta, a major staple food in the developing world, provides a basic carbohydrate diet for over half a billion people living in the tropics. Despite the iron abundance in most soils, cassava provides insufficient iron for humans as the edible roots contain 3-12 times less iron than other traditional food crops such as wheat, maize, and rice. With the recent identification that the beneficial soil bacterium Bacillus subtilis (strain GB03 activates iron acquisition machinery to increase metal ion assimilation in Arabidopsis, the question arises as to whether this plant-growth promoting rhizobacterium (PGPR also augments iron assimilation to increase endogenous iron levels in cassava. Biochemical analyses reveal that shoot-propagated cassava with GB03-inoculation exhibit elevated iron accumulation after 140 days of plant growth as determined by X-ray microanalysis and total foliar iron analysis. Growth promotion and increased photosynthetic efficiency were also observed for greenhouse-grown plants with GB03-exposure. These results demonstrate the potential of microbes to increase iron accumulation in an important agricultural crop and is consistent with idea that microbial signaling can regulate plant photosynthesis.

  17. Isolation of Aureimonas altamirensis, a Brucella canis-like bacterium, from an edematous canine testicle.

    Science.gov (United States)

    Reilly, Thomas J; Calcutt, Michael J; Wennerdahl, Laura A; Williams, Fred; Evans, Tim J; Ganjam, Irene K; Bowman, Jesse W; Fales, William H

    2014-11-01

    Microbiological and histological analysis of a sample from a swollen testicle of a 2-year-old Border Collie dog revealed a mixed infection of the fungus Blastomyces dermatitidis and the Gram-negative bacterium Aureimonas altamirensis. When subjected to an automated microbial identification system, the latter isolate was provisionally identified as Psychrobacter phenylpyruvicus, but the organism shared several biochemical features with Brucella canis and exhibited agglutination, albeit weakly, with anti-B. canis antiserum. Unequivocal identification of the organism was only achieved by 16S ribosomal RNA gene sequencing, ultimately establishing the identity as A. altamirensis. Since its first description in 2006, this organism has been isolated infrequently from human clinical samples, but, to the authors' knowledge, has not been reported from a veterinary clinical sample. While of unknown clinical significance with respect to the pathology observed for the polymicrobial infection described herein, it highlights the critical importance to unambiguously identify the microbe for diagnostic, epidemiological, infection control, and public health purposes. PMID:25292192

  18. A vaccine and diagnostic target for Clostridium bolteae, an autism-associated bacterium.

    Science.gov (United States)

    Pequegnat, Brittany; Sagermann, Martin; Valliani, Moez; Toh, Michael; Chow, Herbert; Allen-Vercoe, Emma; Monteiro, Mario A

    2013-06-10

    Constipation and diarrhea are common in autistic patients. Treatment with antibiotics against bacteria appears to partially alleviate autistic-related symptoms. Clostridium bolteae is a bacterium that has been shown to be overabundant in the intestinal tract of autistic children suffering from gastric intestinal ailments, and as such is an organism that could potentially aggravate gastrointestinal symptoms. We set out to investigate the cell-wall polysaccharides of C. bolteae in order to evaluate their structure and immunogenicity. Our explorations revealed that C. bolteae produces a conserved specific capsular polysaccharide comprised of rhamnose and mannose units: [→3)-α-D-Manp-(1→4)-β-d-Rhap-(1→], which is immunogenic in rabbits. These findings are the first description of a C. bolteae immunogen and indicate the prospect of using this polysaccharide as a vaccine to reduce or prevent C. bolteae colonization of the intestinal tract in autistic patients, and as a diagnostic marker for the rapid detection of C. bolteae in a clinical setting.

  19. Landscape changes influence the occurrence of the melioidosis bacterium Burkholderia pseudomallei in soil in northern Australia.

    Directory of Open Access Journals (Sweden)

    Mirjam Kaestli

    Full Text Available BACKGROUND: The soil-dwelling saprophyte bacterium Burkholderia pseudomallei is the cause of melioidosis, a severe disease of humans and animals in southeast Asia and northern Australia. Despite the detection of B. pseudomallei in various soil and water samples from endemic areas, the environmental habitat of B. pseudomallei remains unclear. METHODOLOGY/PRINCIPAL FINDINGS: We performed a large survey in the Darwin area in tropical Australia and screened 809 soil samples for the presence of these bacteria. B. pseudomallei were detected by using a recently developed and validated protocol involving soil DNA extraction and real-time PCR targeting the B. pseudomallei-specific Type III Secretion System TTS1 gene cluster. Statistical analyses such as multivariable cluster logistic regression and principal component analysis were performed to assess the association of B. pseudomallei with environmental factors. The combination of factors describing the habitat of B. pseudomallei differed between undisturbed sites and environmentally manipulated areas. At undisturbed sites, the occurrence of B. pseudomallei was found to be significantly associated with areas rich in grasses, whereas at environmentally disturbed sites, B. pseudomallei was associated with the presence of livestock animals, lower soil pH and different combinations of soil texture and colour. CONCLUSIONS/SIGNIFICANCE: This study contributes to the elucidation of environmental factors influencing the occurrence of B. pseudomallei and raises concerns that B. pseudomallei may spread due to changes in land use.

  20. Metabolism of nitrodiphenyl ether herbicides by dioxin-degrading bacterium Sphingomonas wittichii RW1.

    Science.gov (United States)

    Keum, Young Soo; Lee, Young Ju; Kim, Jeong-Han

    2008-10-01

    Nitrodiphenyl ether herbicides, including chlomethoxyfen, nitrofen, and oxyfluorfen are potent herbicides. Some metabolites and parent compounds are considered as possible mutagens and endocrine disruptors. Both properties pose serious hygienic and environmental risks. Sphingomonas wittichii RW1 is a well-known degrader of polychlorinated dibenzo- p-dioxins, dibenzofurans, and diphenyl ethers. However, no detailed research of its metabolic activity has been performed against pesticides with a diphenyl ether scaffold. In this study, we report S. wittichii RW1 as a very potent diphenyl ether herbicide-metabolizing bacterium with broad substrate specificity. The structures of metabolites were determined by instrumental analysis and synthetic standards. Most pesticides were rapidly removed from the culture medium in the order of nitrofen > oxyfluorfen > chlomethoxyfen. In general, herbicides were degraded through the initial reduction and N-acetylation of nitro groups, followed by ether bond cleavage. Relatively low concentrations of phenolic and catecholic metabolites throughout the study suggested that these metabolites were rapidly metabolized and incorporated into primary metabolism. These results indicate that strain RW1 has very versatile metabolic activities over a wide range of environmental contaminants. PMID:18778066