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Sample records for pseudomonas sp nars9

  1. Pseudomonas kuykendallii sp. nov.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This is a submission to the list of microorganisms with standing in nomenclature maintained by the International Journal of Systematic and Evolutionary Microbiology. We wish to have Pseudomonas kuykendallii sp. nov. added to the list as a valid species belonging to the genus Pseudomonas. Three str...

  2. Glyphosate catabolism by Pseudomonas sp

    SciTech Connect

    Shinabarger, D.L.

    1986-01-01

    The pathway for the degradation of glyphosate (N-phosphonomethylglycine) by Pseudomonas sp. PG2982 has been determined using metabolic radiolabeling experiments. Radiorespirometry experiments utilizing (3-/sup 14/C) glyphosate revealed that approximately 50-59% of the C3 carbon was oxidized to CO/sub 2/. Fractionation of stationary phase cells labeled with (3-/sup 14/C)glyphosate revealed that from 45-47% of the assimilated C3 carbon is distributed to proteins and that amino acids methionine and serine are highly labeled. The nucleic acid bases adenine and guanine received 90% of the C3 label that was incorporated into nucleic acids, and the only pyrimidine base labeled was thymine. Pulse labeling of PG2982 cells with (3-/sup 14/C)glyphosate revealed that (3-/sup 14/C)sarcosine is an intermediate in glyphosate degradation. Examination of crude extracts prepared from PG2982 cells revealed the presence of an enzyme that oxidizes sarcosine to glycine and formaldehyde. These results indicate that the first step in glyphosate degradation by PG2982 is cleavage of the carbon-phosphorus bond, resulting in the release of sarcosine and a phosphate group. The phosphate group is utilized as a source of phosphorus, and the sarcosine is degraded to glycine and formaldehyde. Phosphonate utilization by Pseudomonas sp. PG2982 was investigated. Each of the ten phosphonates tested were utilized as a sole source of phosphorus by PG2982. Representative compounds tested included alkylphosphonates, 1-amino-substituted alkylphosphonates, amino-terminal phosphonates, and an arylphosphonate. PG2982 cultures degraded phenylphosphonate to benzene and produced methane from methylphosphonate. The data indicate that PG2982 is capable of cleaving the carbon-phosphorus bond of several structurally different phosphonates.

  3. Development and Dynamics of Pseudomonas sp. Biofilms

    PubMed Central

    Tolker-Nielsen, Tim; Brinch, Ulla C.; Ragas, Paula C.; Andersen, Jens Bo; Jacobsen, Carsten Suhr; Molin, Søren

    2000-01-01

    Pseudomonas sp. strain B13 and Pseudomonas putida OUS82 were genetically tagged with the green fluorescent protein and the Discosoma sp. red fluorescent protein, and the development and dynamics occurring in flow chamber-grown two-colored monospecies or mixed-species biofilms were investigated by the use of confocal scanning laser microscopy. Separate red or green fluorescent microcolonies were formed initially, suggesting that the initial small microcolonies were formed simply by growth of substratum attached cells and not by cell aggregation. Red fluorescent microcolonies containing a few green fluorescent cells and green fluorescent microcolonies containing a few red fluorescent cells were frequently observed in both monospecies and two-species biofilms, suggesting that the bacteria moved between the microcolonies. Rapid movement of P. putida OUS82 bacteria inside microcolonies was observed before a transition from compact microcolonies to loose irregularly shaped protruding structures occurred. Experiments involving a nonflagellated P. putida OUS82 mutant suggested that the movements between and inside microcolonies were flagellum driven. The results are discussed in relation to the prevailing hypothesis that biofilm bacteria are in a physiological state different from planktonic bacteria. PMID:11053394

  4. Pseudomonas punonensis sp. nov., isolated from straw.

    PubMed

    Ramos, Elena; Ramírez-Bahena, Martha-Helena; Valverde, Angel; Velázquez, Encarna; Zúñiga, Doris; Velezmoro, Carmen; Peix, Alvaro

    2013-05-01

    During a study of the 'tunta' (frozen-dry potato) production process in Peru, a bacterial strain, LMT03(T), was isolated from the straw grass in which the potatoes are dried. This strain was classified into the genus Pseudomonas on the basis of the 16S rRNA gene sequence analysis, and is most closely related to Pseudomonas argentinensis CH01(T) with 99.3 % identity in this gene and 96 %, 92 % and 86 % identities in rpoB, rpoD and gyrB genes, respectively. Strain LMT03(T) has a single polar flagellum, like other related yellow-pigment-producing pseudomonads. The major quinone is Q-9. The major fatty acids are C18 : 1ω7c in summed feature 8 (40.82 %), C16 : 1ω6c/C16 : 1ω6c in summed feature 3 (23.72 %) and C16 : 0 (15.20 %). The strain produces oxidase but it does not produce gelatinase, indole, urease, arginine dihydrolase or β-galactosidase. Catalase production was very weak after 28 and 48 h incubation on nutrient agar medium. Nitrate reduction is negative. It does not hydrolyse aesculin. The DNA G+C content is 57.8 mol%. DNA-DNA hybridization results showed lower than 52 % relatedness with respect to the type strain of P. argentinensis, CH01(T). These results, together with other phenotypic characteristics, support the definition of a novel species within the genus Pseudomonas, for which the name Pseudomonas punonensis sp. nov. is proposed. The type strain is LMT03(T) ( = LMG 26839(T) = CECT 8089(T)).

  5. Oxidation of polychlorinated biphenyls by Pseudomonas sp. strain LB400 and Pseudomonas pseudoalcaligenes KF707.

    PubMed Central

    Gibson, D T; Cruden, D L; Haddock, J D; Zylstra, G J; Brand, J M

    1993-01-01

    Biphenyl-grown cells and cell extracts prepared from biphenyl-grown cells of Pseudomonas sp. strain LB400 oxidize a much wider range of chlorinated biphenyls than do analogous preparations from Pseudomonas pseudoalcaligenes KF707. These results are attributed to differences in the substrate specificity of the biphenyl 2,3-dioxygenases from both organisms. PMID:8331086

  6. OXIDATION OF POLYCHLORINATED BIPHENYLS BY PSEUDOMONAS SP. STRAIN LB400 AND PSEUDOMONAS PSEUDOALCALIGENES KF707

    EPA Science Inventory

    Biphenyl-grown cells and cell extracts prepared from biphenyl-grown cells of Pseudomonas sp. strain LB400 oxidize a much wider range of chlorinated biphenyls than do analogous preparations from Pseudomonas pseudoalcaligenes KF707. These results are attributed to differences in th...

  7. Recharacterization of Pseudomonas fulva Iizuka and Komagata 1963, and proposals of Pseudomonas parafulva sp. nov. and Pseudomonas cremoricolorata sp. nov.

    PubMed

    Uchino, Masataka; Shida, Osamu; Uchimura, Tai; Komagata, Kazuo

    2001-10-01

    Seven Pseudomonas fulva strains obtained from culture collections were taxonomically studied. The seven strains were separated into three clusters (Clusters I to III) on the basis of 16S rRNA gene sequences, and located phylogenetically in the genus Pseudomonas sensu stricto. Further, the strains were classified into 4 groups (Groups I to IV) on the basis of DNA-DNA similarity. As a result, Cluster I was split into Groups I and II. Group I included the type strain of P. fulva and two strains, and levels of DNA-DNA similarity ranged from 88 to 100% among the strains. Group II contained two strains, and the level between the two strains ranged from 91 to 100%. Group III consisted of one strain. Group IV included one strain, and this strain showed a high level of DNA-DNA similarity with the type strain of Pseudomonas straminea NRIC 0164(T). Clusters II and III corresponded to Groups III and IV, respectively. The four groups were separated from one another and from related Pseudomonas species at the level from 3 to 45% of DNA-DNA similarity. The strains of Groups I, II, and III had ubiquinone 9 as the major quinone. According to numerical analysis by the use of 133 phenotypic characteristics, the seven P. fulva strains were split into four phenons (Phenons I to IV). The groups by DNA-DNA similarity corresponded well with the phenons produced by numerical taxonomy, and differential characteristics were recognized. Consequently, Group I was regarded as P. fulva because the type strain (NRIC 0180(T)) of this species was included in this group. Strains in Group II were identified as a new species, Pseudomonas parafulva sp. nov., and the type strain is AJ 2129 (=IFO 16636=JCM 11244=NRIC 0501). NRIC 0181 in Group III was identified as a new species, Pseudomonas cremoricolorata sp. nov., and the type strain is NRIC 0181 (=IFO 16634=JCM 11246). NRIC 0182 in Group IV was identified as P. straminea on the basis of the high level of DNA-DNA similarity with the type strain of this

  8. Pseudomonas pachastrellae sp. nov., isolated from a marine sponge.

    PubMed

    Romanenko, Lyudmila A; Uchino, Masataka; Falsen, Enevold; Frolova, Galina M; Zhukova, Natalia V; Mikhailov, Valery V

    2005-03-01

    Two Gram-negative, non-fermentative, non-denitrifying, non-pigmented, rod-shaped bacteria that were motile by means of polar flagella, designated strains KMM 330(T) and KMM 331, were isolated from a deep-sea sponge specimen and subjected to a polyphasic taxonomic study. The new isolates exhibited 16S rRNA gene sequence similarity of 99.9 %, and their mean level of DNA-DNA relatedness was 82 %. Phylogenetic analysis based on their 16S rRNA gene sequences placed the strains within the genus Pseudomonas as an independent deep clade. Strain KMM 330(T) shared highest sequence similarity (96.3 %) with each of Pseudomonas fulva NRIC 0180(T), Pseudomonas parafulva AJ 2129(T) and Pseudomonas luteola IAM 13000(T); sequence similarity to other recognized species of the genus Pseudomonas was below 95.7 %. The marine sponge isolates KMM 330(T) and KMM 331 could be distinguished from the other recognized Pseudomonas species based on a unique combination of their phenotypic characteristics, including growth in 8 or 10 % NaCl, the absence of pigments, the inability to denitrify and lack of carbohydrate utilization. On the basis of phylogenetic analysis, physiological and biochemical characterization, strains KMM 330(T) and KMM 331 should be classified as a novel species of the genus Pseudomonas, for which the name Pseudomonas pachastrellae sp. nov. is proposed. The type strain is KMM 330(T) (=JCM 12285(T)=NRIC 0583(T)=CCUG 46540(T)).

  9. Metabolism of glyphosate in Pseudomonas sp. strain LBr.

    PubMed

    Jacob, G S; Garbow, J R; Hallas, L E; Kimack, N M; Kishore, G M; Schaefer, J

    1988-12-01

    Metabolism of glyphosate (N-phosphonomethylglycine) by Pseudomonas sp. strain LBr, a bacterium isolated from a glyphosate process waste stream, was examined by a combination of solid-state 13C nuclear magnetic resonance experiments and analysis of the phosphonate composition of the growth medium. Pseudomonas sp. strain LBr was capable of eliminating 20 mM glyphosate from the growth medium, an amount approximately 20-fold greater than that reported for any other microorganism to date. The bacterium degraded high levels of glyphosate, primarily by converting it to aminomethylphosphonate, followed by release into the growth medium. Only a small amount of aminomethylphosphonate (about 0.5 to 0.7 mM), which is needed to supply phosphorus for growth, could be metabolized by the microorganism. Solid-state 13C nuclear magnetic resonance analysis of strain LBr grown on 1 mM [2-13C,15N]glyphosate showed that about 5% of the glyphosate was degraded by a separate pathway involving breakdown of glyphosate to glycine, a pathway first observed in Pseudomonas sp. strain PG2982. Thus, Pseudomonas sp. strain LBr appears to possess two distinct routes for glyphosate detoxification.

  10. Production of extracellular water-insoluble polysaccharide from Pseudomonas sp.

    PubMed

    Cui, Jian-Dong; Qiu, Ji Qing

    2012-05-16

    Curdlan is a microbial polysaccharide composed exclusively of β-(1,3)-linked glucose residues. Until now only bacteria belonging to the Alcaligenes and Agrobacterium species have been reported to produce Curdlan. In this study, a bacterium capable of producing extracellular Curdlan, identified as Pseudomonas sp. on the basis of 16S rDNA gene sequencing, was isolated from soil samples. From the HPLC, permethylation linkage analysis, (13)C NMR, and FT-IR analytical data, the polysaccharide consisted exclusively of glucose; the most prominent sugar was 1,3-linked glucose, and most glycosidic bonds joining these sugar residues were of the β-type. This also supported that the exopolysaccharide produced by Pseudomonas sp. was actually Curdlan. In addition, the Pseudomonas sp. was studied for the production of Curdlan by conventional "one-factor-at-a-time technique" and response surface methodology (RSM). It was observed that glucose and yeast extract were the most suitable carbon source and nitrogen source for Curdlan production, respectively. By using RSM, Curdlan production was increased significantly by 188%, from 1.25 to 2.35 g/L, when the strain was cultivated in the optimal condition developed by RSM, and the highest Curdlan production rate of 0.81 g/(L h) was obtained. To the best of the authors' knowledge, this is the first report on Curdlan production by Pseudomonas sp.

  11. Pseudomonas helmanticensis sp. nov., isolated from forest soil.

    PubMed

    Ramírez-Bahena, Martha-Helena; Cuesta, Maria José; Flores-Félix, José David; Mulas, Rebeca; Rivas, Raúl; Castro-Pinto, Joao; Brañas, Javier; Mulas, Daniel; González-Andrés, Fernando; Velázquez, Encarna; Peix, Alvaro

    2014-07-01

    A bacterial strain, OHA11(T), was isolated during the course of a study of phosphate-solubilizing bacteria occurring in a forest soil from Salamanca, Spain. The 16S rRNA gene sequence of strain OHA11(T) shared 99.1% similarity with respect to Pseudomonas baetica a390(T), and 98.9% similarity with the type strains of Pseudomonas jessenii, Pseudomonas moorei, Pseudomonas umsongensis, Pseudomonas mohnii and Pseudomonas koreensis. The analysis of housekeeping genes rpoB, rpoD and gyrB confirmed its phylogenetic affiliation to the genus Pseudomonas and showed similarities lower than 95% in almost all cases with respect to the above species. Cells possessed two polar flagella. The respiratory quinone was Q9. The major fatty acids were C16 : 0, C18 : 1ω7c and summed feature 3 (C16 : 1ω7c/iso-C15 : 0 2-OH). The strain was oxidase-, catalase- and urease-positive, positive for arginine dihydrolase but negative for nitrate reduction, β-galactosidase production and aesculin hydrolysis. It was able to grow at 31 °C and at pH 11. The DNA G+C content was 58.1 mol%. DNA-DNA hybridization results showed values lower than 49% relatedness with respect to the type strains of the seven closest related species. Therefore, the combined genotypic, phenotypic and chemotaxonomic data support the classification of strain OHA11(T) to a novel species of the genus Pseudomonas, for which the name Pseudomonas helmanticensis sp. nov. is proposed. The type strain is OHA11(T) ( = LMG 28168(T) = CECT 8548(T)).

  12. Pseudomonas soli sp. nov., a novel producer of xantholysin congeners.

    PubMed

    Pascual, Javier; García-López, Marina; Carmona, Cristina; Sousa, Thiciana da S; de Pedro, Nuria; Cautain, Bastien; Martín, Jesús; Vicente, Francisca; Reyes, Fernando; Bills, Gerald F; Genilloud, Olga

    2014-09-01

    A chemoorganotrophic Gram-negative bacterium was isolated by means of a diffusion sandwich system from a soil sample from the Sierra Nevada National Park, Spain. Strain F-279,208(T) was oxidase and catalase positive, strictly aerobic, non-spore-forming and motile by single polar flagellum. Phylogenetic analysis of the 16S rRNA, gyrB, rpoB and rpoD genes revealed that strain F-279,208(T) belongs to the Pseudomonas putida group with Pseudomonas mosselii and Pseudomonas entomophila as its closest relatives. DNA-DNA hybridization assays and phenotypic traits confirmed that this strain belongs to a novel species of the genus Pseudomonas, for which the name Pseudomonas soli sp. nov. is proposed. The type strain is F-279,208(T) (=DSM 28043(T)=LMG 27941(T)), and during fermentation it produces xantholysins, a family of lipodepsipeptides. The major compound, xantholysin A, showed an interesting activity in a RCC4 kidney tumor cell line with inactivation of VHL linked with the HIF pathway, without any cytotoxic effects against other human tumor cell lines tested including, liver, pancreas and breast.

  13. Pseudomonas chengduensis sp. nov., isolated from landfill leachate.

    PubMed

    Tao, Yong; Zhou, Yan; He, Xiaohong; Hu, Xiaohong; Li, Daping

    2014-01-01

    Strain MBR(T) was isolated from landfill leachate in a solid-waste disposal site in Chengdu, Sichuan, China. An analysis of 16S rRNA gene sequences revealed that the isolate was closely related to members of the genus Pseudomonas, sharing the highest sequence similarities with Pseudomonas toyotomiensis HT-3(T) (99.8 %), Pseudomonas alcaliphila AL15-21(T) (99.7 %) and Pseudomonas oleovorans ATCC 8062(T) (99.4 %). Multi-locus sequence analysis based on three housekeeping genes (gyrB, rpoB and rpoD) provided higher resolution at the species level than that based on 16S rRNA gene sequences, which was further confirmed by less than 70 % DNA-DNA relatedness between the new isolate and P. toyotomiensis HT-3(T) (61.3 %), P. alcaliphila AL15-21(T) (51.5 %) and P. oleovorans ATCC 8062(T) (57.8 %). The DNA G+C content of strain MBR(T) was 61.9 mol% and the major ubiquinone was Q-9. The major cellular fatty acids (>10 %) were C18 : 1ω7c and/or C18 : 1ω6c, C16 : 0, and C16 : 1ω7c and/or C16 : 1ω6c. Polyphasic analysis indicates that strain MBR(T) represents a novel species of the genus Pseudomonas, for which the name Pseudomonas chengduensis sp. nov. is proposed. The type strain is MBR(T) ( = CGMCC 2318(T) = DSM 26382(T)).

  14. Pseudomonas asturiensis sp. nov., isolated from soybean and weeds.

    PubMed

    González, Ana J; Cleenwerck, Ilse; De Vos, Paul; Fernández-Sanz, Ana M

    2013-07-01

    Five strains of gram negative bacteria, isolated from soybean (LPPA 221(T), 222 and 223) and weeds (LPPA 816 and 1442), were analyzed by a polyphasic approach. The isolates showed variation in their phenotypic traits and were placed in the Pseudomonas fluorescens lineage, based on 16S rRNA gene sequence phylogeny, as a single but well separated cluster. MLSA analysis based on gyrB and rpoD sequences clustered the strains in a single branch in the Pseudomonas syringae group, and revealed P. viridiflava as closest relative. DNA-DNA hybridizations showed medium levels of DNA-DNA relatedness with the type strain of P. viridiflava (50%) and lower levels (<32%) with other type strains of the P. syringae group, supporting classification within a novel species of the genus Pseudomonas. The strains can be distinguished from species of the P. syringae group by the fatty acid C17:0 cyclo that is present in a low amount (2.5%) and from P. viridiflava by their inability to assimilate d-tartrate and d-sorbitol, and by the formation of red colonies on TTC medium. For this new species, the name Pseudomonas asturiensis sp. nov. is proposed. The type strain is LPPA 221(T) (=LMG 26898(T)=CECT 8095(T)).

  15. Pseudomonas zhaodongensis sp. nov., isolated from saline and alkaline soils.

    PubMed

    Zhang, Lei; Pan, Yuanyuan; Wang, Kaibiao; Zhang, Xiaoxia; Zhang, Cheng; Zhang, Shuang; Fu, Xiaowei; Jiang, Juquan

    2015-03-01

    Strain NEAU-ST5-21(T) was isolated from saline and alkaline soils in Zhaodong City, Heilongjiang Province, China. It was aerobic, Gram-stain-negative, rod-shaped and motile with a polar flagellum. It produced yellow-orange colonies with a smooth surface, and grew in the presence of 0-5 % (w/v) NaCl (optimum 0 %, w/v), at temperatures of 20-40 °C (optimum 28 °C) and at pH 7-11 (optimum pH 7). Phylogenetic analyses based on the separate 16S rRNA gene sequences and concatenated 16S rRNA, gyrB and rpoD gene sequences indicated that strain NEAU-ST5-21(T) belongs to the genus Pseudomonas in the class Gammaproteobacteria. The most closely related species is Pseudomonas xanthomarina, whose type strain (KMM 1447(T)) showed gene sequence similarities of 99.0 % for 16S rRNA, 81.8 % for gyrB and 85.0 % for rpoD with strain NEAU-ST5-21(T). DNA-DNA hybridization values between strain NEAU-ST5-21(T) and P. xanthomarina DSM 18231(T), Pseudomonas kunmingensis CGMCC 1.12273(T), Pseudomonas stutzeri DSM 5190(T), Pseudomonas oleovorans subsp. lubricantis DSM 21016(T), Pseudomomas chengduensis CGMCC 2318(T), Pseudomonas alcaliphila DSM 17744(T) and Pseudomonas toyotomiensis DSM 26169(T) were 52±0 % to 25±2 %. The DNA G+C content of strain NEAU-ST5-21(T) was 65 mol%. The major fatty acids (>10 %) were C18 : 1ω7c and/or C18 : 1ω6c, C16 : 1ω7c and/or C16 : 1ω6c and C16 : 0, the predominant respiratory quinone was ubiquinone 9, and polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, one unknown phospholipid, phosphatidylglycerol, one unknown aminolipid, one unknown lipid and a glycolipid. The proposed name is Pseudomonas zhaodongensis sp. nov., NEAU-ST5-21(T) ( = ACCC 06362(T) = DSM 27559(T)) being the type strain.

  16. Mineralization of a Malaysian crude oil by Pseudomonas sp. and Achromabacter sp. isolated from coastal waters

    SciTech Connect

    Ahmad, J.; Ahmad, M.F.

    1995-12-31

    Regarded as being a potentially effective tool to combat oil pollution, bioremediation involves mineralization, i.e., the conversion of complex hydrocarbons into harmless CO{sub 2} and water by action of microorganisms. Therefore, in achieving optimum effectiveness from the application of these products on crude oil in local environments, the capability of the bacteria to mineralize hydrocarbons was evaluated. The microbial laboratory testing of mineralization on local oil degraders involved, first, isolation of bacteria found at a port located on the west coast of Peninsular Malaysia. Subsequently, these bacteria were identified by means of Biomereux`s API 20E and 20 NE systems and later screened by their growth on a Malaysian crude oil. Selected strains of Pseudomonas sp. and Achromabacter sp. were then exposed individually to a similar crude oil in a mineralization unit and monitored for 16 days for release of CO{sub 2}. Pseudomonas paucimobilis was found to produce more CO{sub 2} than Achromobacter sp. When tested under similar conditions, mixed populations of these two taxa produced more CO{sub 2} than that produced by any individual strain. Effective bioremediation of local crude in Malaysian waters can therefore be achieved from biochemically developed Pseudomonas sp. strains.

  17. Biodegradation of 2,4-dinitrotoluene by a Pseudomonas sp.

    PubMed Central

    Spanggord, R J; Spain, J C; Nishino, S F; Mortelmans, K E

    1991-01-01

    Previous studies of the biodegradation of nonpolar nitroaromatic compounds have suggested that microorganisms can reduce the nitro groups but cannot cleave the aromatic ring. We report here the initial steps in a pathway for complete biodegradation of 2,4-dinitrotoluene (DNT) by a Pseudomonas sp. isolated from a four-member consortium enriched with DNT. The Pseudomonas sp. degraded DNT as the sole source of carbon and energy under aerobic conditions with stoichiometric release of nitrite. During induction of the enzymes required for growth on DNT, 4-methyl-5-nitrocatechol (MNC) accumulated transiently in the culture fluid when cells grown on acetate were transferred to medium containing DNT as the sole carbon and energy source. Conversion of DNT to MNC in the presence of 18O2 revealed the simultaneous incorporation of two atoms of molecular oxygen, which demonstrated that the reaction was catalyzed by a dioxygenase. Fully induced cells degraded MNC rapidly with stoichiometric release of nitrite. The results indicate an initial dioxygenase attack at the 4,5 position of DNT with the concomitant release of nitrite. Subsequent reactions lead to complete biodegradation and removal of the second nitro group as nitrite. PMID:1781682

  18. Dienelactone hydrolase from Pseudomonas sp. strain B13.

    PubMed Central

    Ngai, K L; Schlömann, M; Knackmuss, H J; Ornston, L N

    1987-01-01

    Dienelactone hydrolase (EC 3.1.1.45) catalyzes the conversion of cis- or trans-4-carboxymethylenebut-2-en-4-olide (dienelactone) to maleylacetate. An approximately 24-fold purification from extracts of 3-chlorobenzoate-grown Pseudomonas sp. strain B13 yielded a homogeneous preparation of the enzyme. The purified enzyme crystallized readily and proved to be a monomer with a molecular weight of about 30,000. Each dienelactone hydrolase molecule contains two cysteinyl side chains. One of these was readily titrated by stoichiometric amounts of p-chloromercuribenzoate, resulting in inactivation of the enzyme; the inactivation could be reversed by the addition of dithiothreitol. The other cysteinyl side chain appeared to be protected in the native protein against chemical reaction with p-chloromercuribenzoate. The properties of sulfhydryl side chains in dienelactone hydrolase resembled those that have been characterized for bacterial 4-carboxymethylbut-3-en-4-olide (enol-lactone) hydrolases (EC 3.1.1.24), which also are monomers with molecular weights of about 30,000. The amino acid composition of the dienelactone hydrolase resembled the amino acid composition of enol-lactone hydrolase from Pseudomonas putida, and alignment of the NH2-terminal amino acid sequence of the dienelactone hydrolase with the corresponding sequence of an Acinetobacter calcoaceticus enol-lactone hydrolase revealed sequence identity at 8 of the 28 positions. These observations foster the hypothesis that the lactone hydrolases share a common ancestor. The lactone hydrolases differed in one significant property: the kcat of dienelactone hydrolase was 1,800 min-1, an order of magnitude below the kcat observed with enol-lactone hydrolases. The relatively low catalytic activity of dienelactone hydrolase may demand its production at the high levels observed for induced cultures of Pseudomonas sp. strain B13. PMID:3804973

  19. Draft Genome Sequence of Pseudomonas sp. LAB-08 Isolated from Trichloroethene-Contaminated Aquifer Soil

    PubMed Central

    Aziz, Fatma A. A.; Inuzuka, Yuma; Tashiro, Yosuke

    2016-01-01

    Pseudomonas sp. LAB-08 was isolated from a phenol-fed bioreactor constructed with contaminated aquifer soil as the inoculum. Strain LAB-08 utilized phenol as a sole carbon and energy source. Here, we report the genome sequence and annotation of Pseudomonas sp. LAB-08. PMID:27660772

  20. Pseudomonas salegens sp. nov., a halophilic member of the genus Pseudomonas isolated from a wetland.

    PubMed

    Amoozegar, Mohammad Ali; Shahinpei, Azadeh; Sepahy, Abbas Akhavan; Makhdoumi-Kakhki, Ali; Seyedmahdi, Shima Sadat; Schumann, Peter; Ventosa, Antonio

    2014-10-01

    A novel Gram-stain-negative, aerobic, non-endospore-forming, non-pigmented, rod-shaped, slightly halophilic bacterium, designated GBPy5(T), was isolated from aquatic plants of the Gomishan wetland, Iran. Cells of strain GBPy5(T) were motile. Growth occurred with between 1 and 10% (w/v) NaCl and the isolate grew optimally with 3% (w/v) NaCl. The optimum pH and temperature for growth of the strain were pH 8.0 and 30 °C, respectively, while it was able to grow over a pH range of 6.5-9.0 and a temperature range of 4-35 °C. Phylogenetic analysis, based on 16S rRNA gene sequences, revealed that strain GBPy5(T) is a member of the genus Pseudomonas forming a monophyletic branch. The novel strain exhibited 16S rRNA gene sequence similarity of 95.4% with type strains of Pseudomonas guariconensis PCAVU11(T) and Pseudomonas sabulinigri J64(T), respectively. The major cellular fatty acids of the isolate were C18:1ω7c (37.8%), C16:0 (14.9%), C16:1ω7c (12.9%), C12:0 3-OH (7.1%) and C12:0 (7.0%). The polar lipid pattern of strain GBPy5(T) comprised phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine and one phospholipid. Ubiquinone 9 (Q-9) was the predominant lipoquinone. The G+C content of the genomic DNA of strain GBPy5(T) was 59.2 mol%. On the basis of the phenotypic and phylogenetic data, strain GBPY5(T) represents a novel species of the genus Pseudomonas, for which the name Pseudomonas salegens sp. nov. is proposed. The type strain is GBPy5(T) ( = IBRC-M 10762(T) = CECT 8338(T)).

  1. Pseudomonas matsuisoli sp. nov., isolated from a soil sample.

    PubMed

    Lin, Shih-Yao; Hameed, Asif; Hung, Mei-Hua; Liu, You-Cheng; Hsu, Yi-Han; Young, Li-Sen; Young, Chiu-Chung

    2015-03-01

    An aerobic, Gram-stain-negative, rod-shaped and polar-flagellated bacterium, designated strain CC-MHH0089(T), was isolated from a soil sample taken on Matsu Island (Taiwan). Strain CC-MHH0089(T) grew at 15-30 °C and pH 5.0-10.0 and tolerated ≤8 % (w/v) NaCl. 16S rRNA gene sequence analysis showed high pairwise sequence similarity to Pseudomonas azotifigens 6H33b(T) (97.3 %) and Pseudomonas balearica SP1402(T) (96.7 %) and lower sequence similarity to other strains (<96.0 %). In DNA-DNA reassociation experiments, the relatedness of strain CC-MHH0089(T) to P. azotifigens JCM 12708(T) was 38.3 % (reciprocal value 19.5 %). Evolutionary trees reconstructed on the basis of 16S rRNA, gyrB and rpoB gene sequences revealed a varying phylogenetic neighbourhood of strain CC-MHH0089(T) with regard to the most closely related type strains. The predominant quinone system was ubiquinone 9 (Q-9) and the DNA G+C content was 63.6 mol%. The major fatty acids were C12 : 0, C16 : 0, C17 : 0, C19 : 0 cyclo ω8c and summed features 2 (C14 : 0 3-OH/iso-C16 : 1 I), 3 (C16 : 1ω7c/C16 : 1ω6c) and 8 (C18 : 1ω7c/C18 : 1ω6c). The major polar lipids were phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine and diphosphatidylglycerol. According to its distinct phylogenetic, phenotypic and chemotaxonomic features, strain CC-MHH0089(T) is proposed to represent a novel species within the genus Pseudomonas, for which the name Pseudomonas matsuisoli sp. nov. is proposed. The type strain is CC-MHH0089(T) ( = BCRC 80771(T) = JCM 30078(T)).

  2. Pseudomonas salina sp. nov., isolated from a salt lake.

    PubMed

    Zhong, Zhi-Ping; Liu, Ying; Hou, Ting-Ting; Liu, Hong-Can; Zhou, Yu-Guang; Wang, Fang; Liu, Zhi-Pei

    2015-09-01

    A Gram-staining-negative, facultatively aerobic bacterium, strain XCD-X85(T), was isolated from Xiaochaidan Lake, a salt lake (salinity 9.9%, w/v) in Qaidam basin, Qinghai province, China. Its taxonomic position was determined by using a polyphasic approach. Cells of strain XCD-X85(T) were non-endospore-forming rods, 0.4-0.6 μm wide and 1.0-1.6 μm long, and motile by means of a single polar flagellum. Strain XCD-X85(T) was catalase- and oxidase-positive. Growth was observed in the presence of 0-12.0% (w/v) NaCl (optimum, 1.0-2.0%) and at 4-35 °C (optimum, 25-30 °C) and pH 6.5-10.5 (optimum, pH 8.0-8.5). Strain XCD-X85(T) contained (>10%) summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), C12 : 0, C16 : 0 and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) as the predominant fatty acids. The major respiratory quinone was ubiquinone 9 (Q-9). The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. The DNA G+C content was 57.4 mol%. Phylogenetic trees based on 16S rRNA gene sequences showed that strain XCD-X85(T) was associated with the genus Pseudomonas, and showed highest 16S rRNA gene sequence similarities to Pseudomonas pelagia CL-AP6(T) (99.0%) and Pseudomonas bauzanensis BZ93(T) (96.8%). DNA-DNA relatedness of strain XCD-X85T to P. pelagia JCM 15562(T) was 19 ± 1%. On the basis of the data presented above, it is concluded that strain XCD-X85(T) represents a novel species of the genus Pseudomonas, for which the name Pseudomonas salina sp. nov. is proposed. The type strain is XCD-X85(T) ( = CGMCC 1.12482(T) = JCM 19469(T)).

  3. Biodegradation of 2-nitrotoluene by Pseudomonas sp. strain JS42.

    PubMed Central

    Haigler, B E; Wallace, W H; Spain, J C

    1994-01-01

    A strain of Pseudomonas sp. was isolated from nitrobenzene-contaminated soil and groundwater on 2-nitrotoluene as the sole source of carbon, energy, and nitrogen. Bacterial cells growing on 2-nitrotoluene released nitrite into the growth medium. The isolate also grew on 3-methylcatechol, 4-methylcatechol, and catechol. 2-Nitrotoluene, 3-methylcatechol, and catechol stimulated oxygen consumption by intact cells regardless of the growth substrate. Crude extracts from the isolate contained catechol 2,3-dioxygenase and 2-hydroxy-6-oxohepta-2,4-dienoate hydrolase activity. The results suggest that 2-nitrotoluene is subject to initial attack by a dioxygenase enzyme that forms 3-methylcatechol with concomitant release of nitrite. The 3-methylcatechol is subsequently degraded via the meta ring fission pathway. PMID:7944378

  4. Anthranilate degradation by a cold-adapted Pseudomonas sp.

    PubMed

    Kim, Dockyu; Yoo, Miyoun; Kim, Eungbin; Hong, Soon Gyu

    2015-03-01

    An alpine soil bacterium Pseudomonas sp. strain PAMC 25931 was characterized as eurypsychrophilic (both psychrophilic and mesotolerant) with a broad temperature range of 5-30 °C both for anthranilate (2-aminobenzoate) degradation and concomitant cell growth. Two degradative gene clusters (antABC and catBCA) were detected from a fosmid clone in the PAMC 25931 genomic library; each cluster was confirmed to be specifically induced by anthranilate. When expressed in Escherichia coli, the recombinant AntABC (anthranilate 1,2-dioxygenase, AntDO) converted anthranilate into catechol, exhibiting strict specificity toward anthranilate. Recombinant CatA (catechol 1,2-dioxygenase, C12O) from the organism was active over a broad temperature range (5-37 °C). However, CatA rapidly lost the enzyme activity when incubated at above 25 °C. For example, 1 h-preincubation at 37 °C resulted in 100% loss of enzyme activity, while a counterpart from mesophilic Pseudomonas putida mt-2 did not show any negative effect on the initial enzyme activity. These results suggest that CatA is a new cold-adapted thermolabile enzyme, which might be a product through the adaptation process of PAMC 25931 to naturally cold environments and contribute to its ability to grow on anthranilate there.

  5. Kinetics of styrene biodegradation by Pseudomonas sp. E-93486.

    PubMed

    Gąszczak, Agnieszka; Bartelmus, Grażyna; Greń, Izabela

    2012-01-01

    The research into kinetics of styrene biodegradation by bacterial strain Pseudomonas sp. E-93486 coming from VTT Culture Collection (Finland) was presented in this work. Microbial growth tests in the presence of styrene as the sole carbon and energy source were performed both in batch and continuous cultures. Batch experiments were conducted for initial concentration of styrene in the liquid phase changed in the range of 5-90 g m(-3). The Haldane model was found to be the best to fit the kinetic data, and the estimated constants of the equation were: μ (m) = 0.1188 h(-1), K(S) = 5.984 mg l(-1), and K (i) = 156.6 mg l(-1). The yield coefficient mean value [Formula in text] for the batch culture was 0.72 g(dry cells weight) (g(substrate))(-1). The experiments conducted in a chemostat at various dilution rates (D = 0.035-0.1 h(-1)) made it possible to determine the value of the coefficient for maintenance metabolism m (d) = 0.0165 h(-1) and the maximum yield coefficient value [Formula in text]. Chemostat experiments confirmed the high value of yield coefficient [Formula in text] observed in the batch culture. The conducted experiments showed high activity of the examined strain in the styrene biodegradation process and a relatively low sensitivity to inhibition of its growth at higher concentrations of styrene in the solution. Such exceptional features of Pseudomonas sp. E-93486 make this bacterial strain the perfect candidate for technical applications.

  6. Pseudomonas hussainii sp. nov., isolated from droppings of a seashore bird, and emended descriptions of Pseudomonas pohangensis, Pseudomonas benzenivorans and Pseudomonas segetis.

    PubMed

    Hameed, Asif; Shahina, Mariyam; Lin, Shih-Yao; Liu, You-Cheng; Young, Chiu-Chung

    2014-07-01

    Two Gram-staining-negative, aerobic, rod-shaped, non-spore-forming bacterial strains that are motile by a monopolar flagellum, designated CC-AMH-11(T) and CC-AMHZ-5, were isolated from droppings of a seashore bird off the coast of Hualien, Taiwan. The strains showed 99.7% mutual pairwise 16S rRNA gene sequence similarity, while exhibiting <96.2% sequence similarity to strains of other species of the genus Pseudomonas (95.7-95.9% similarity with type species, Pseudomonas aeruginosa LMG 1242T), and formed a distinct co-phyletic lineage in the phylogenetic trees. The common major fatty acids (>5% of the total) were C18 : 1ω7c and/or C18 : 1ω6c (summed feature 8), C16 : 1ω6c and/or C16 : 1ω7c (summed feature 3), C16 : 0 and C12 : 0. Phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylserine, an unidentified lipid and an unidentified phospholipid were detected as common polar lipids. The DNA G+C contents of strains CC-AMH-11(T) and CC-AMHZ-5 were 61.1 and 61.6 mol%, respectively. The common major respiratory quinone was ubiquinone 9 (Q-9), and the predominant polyamine was putrescine. The DNA-DNA hybridization obtained between the two strains was 79.0% (reciprocal value 89.4% using CC-AMHZ-5 DNA as the probe). The very high 16S rRNA gene sequence similarity and DNA-DNA relatedness and the poorly distinguishable phenotypic features witnessed between CC-AMH-11(T) and CC-AMHZ-5 suggested unambiguously that they are two distinct strains of a single genomic species. However, the strains also showed several genotypic and phenotypic characteristics that distinguished them from other closely related species of Pseudomonas. Thus, the strains are proposed to represent a novel species of Pseudomonas, for which the name Pseudomonas hussainii sp. nov. is proposed. The type strain is CC-AMH-11(T) ( = JCM 19513(T) = BCRC 80696(T)); a second strain of the same species is CC-AMHZ-5 ( = JCM 19512 = BCRC 80697). In addition, emended descriptions

  7. Identification and genomic analysis of antifungal property of a tomato root endophyte Pseudomonas sp. p21.

    PubMed

    Ma, Rongqin; Cao, Yi; Cheng, Zhiqiang; Lei, Shaonan; Huang, Wei; Li, Xin; Song, Yongkang; Tian, Baoyu

    2017-03-01

    Pseudomonas sp., which occupy a variety of ecological niches, have been widely studied for their versatile metabolic capacity to promote plant growth, suppress microbial pathogens, and induce systemic resistance in plants. In this study, a Pseudomonas sp. strain p21, which was isolated from tomato root endophytes, was identified as having antagonism against Aspergillus niger. Further analysis showed that this strain had the ability to biosynthesise siderophores and was less effective in inhibiting the growth of A. niger with the supplementation of Fe(3+) in the agar medium. Genomic sequencing and the secondary metabolite cluster analysis demonstrated that Pseudomonas sp. p21 harboured 2 pyoverdine biosynthetic gene clusters, which encode compounds with predicted core structures and two variable tetra-peptide or eleven-peptide chains. The results indicated that siderophore-mediated competition for iron might be an important mechanism in Pseudomonas suppression of the fungal pathogen A. niger and in microbe-pathogen-plant interactions.

  8. Kinetics of p-nitrophenol mineralization by a Pseudomonas sp. : effects of sound substrates

    SciTech Connect

    Schmidt, S.K.; Scow, K.M.; Alexander, M.

    1987-11-01

    The kinetics of simultaneous mineralization of p-nitrophenol (PNP) and glucose by Pseudomonas sp. were evaluated by nonlinear regression analysis. Pseudomonas sp. did not mineralize PNP at a concentration of 10 ng/ml but metabolized it at concentrations of 50 ng/ml or higher. The K/sub s/ value for PNP mineralization by Pseudomonas sp. was 1.1 ..mu..g/ml, whereas the K/sub s/ values for phenol and glucose mineralization were 0.10 and 0.25 ..mu..g/ml respectively. The addition of glucose to the media did not enable Pseudomonas sp. to mineralize 10 ng of PNP per ml but did enhance the degradation of higher concentrations of PNP. This enhanced degradation resulted from the simultaneous use of glucose and PNP and the increased rate of growth of Pseudomonas sp. on glucose. The Monod equation and a dual-substrate model fit these data equally well. The dual-substrate model was used to analyze the data because the theoretical assumptions of the Monod equation were not met. Phenol inhibited PNP mineralization and changed the kinetics of PNP mineralization so that the pattern appeared to reflect growth, when in fact growth was not occurring. Thus, the fitting of models to substrate depletion curves may lead to erroneous interpretations of data if the effects of second substrates on population dynamics are not considered.

  9. Pseudomonas yangmingensis sp. nov., an alkaliphilic denitrifying species isolated from a hot spring.

    PubMed

    Wong, Biing-Teo; Lee, Duu-Jong

    2014-01-01

    This study isolated and identified a facultative, alkaliphilic, denitrifying Pseudomonas strain designed as CRS1 from a hot spring, Yang-Ming Mountain, Taiwan. The biochemical characterization, phenotypic characteristics and phylogenetic relationship of strain CRS1 were studied. On the basis of the 16S rRNA sequence similarity, phenotypic and genotypic characteristics and chemotaxonomic data, the strain CRS1 represents a novel species of the genus Pseudomonas, for which the name Pseudomonas yangmingensis sp. nov., is proposed. The strain CRS1 is a facultative autotrophic bacterium that has capability of mixotrophic and heterotrophic denitrification.

  10. Comparative studies on crosslinked and uncrosslinked natural rubber biodegradation by Pseudomonas sp.

    PubMed

    Roy, Ram Vinod; Das, Mithu; Banerjee, Rintu; Bhowmick, Anil K

    2006-12-01

    A comparative study on biodegradation of di-cumyl peroxide (DCP) crosslinked and uncrosslinked natural rubber by Pseudomonas sp. was carried out. Decrease in organic carbon content along with the changes in tensile strength of the treated rubber, both DCP crosslinked and uncrosslinked natural rubber, indicated rubber hydrocarbon utilization by the Pseudomonas sp. A decrease in 60.88% MPa and 41.66% MPa was observed after five month's old treated uncrosslinked natural rubber and DCP crosslinked rubber, respectively. Biodegradation was more pronounced in natural uncrosslinked rubber, which was further confirmed by the formation of aldehydic compounds with decrease in CH2 stretching frequencies.

  11. Draft genome sequence of Pseudomonas sp. strain M47T1, carried by Bursaphelenchus xylophilus isolated from Pinus pinaster.

    PubMed

    Proença, Diogo Neves; Espírito Santo, Christophe; Grass, Gregor; Morais, Paula V

    2012-09-01

    The draft genome sequence of Pseudomonas sp. strain M47T1, carried by the Bursaphelenchus xylophilus pinewood nematode, the causative agent of pine wilt disease, is presented. In Pseudomonas sp. strain M47T1, genes that make this a plant growth-promoting bacterium, as well as genes potentially involved in nematotoxicity, were identified.

  12. Pseudomonas creosotenesis sp. n., a Creosote-tolerant Marine Bacterium

    PubMed Central

    O'Neill, Thomas B.; Drisko, Richard W.; Hochman, Harry

    1961-01-01

    In a study of the marine biological environment in which creosoted pilings are located, a previously unreported species of bacteria was isolated. This species was detected on creosoted piling from 11 widely differing locations and was the predominant species of bacteria found on these piling. The new organism was identified as a gram-negative rod belonging to the genus Pseudomonas and has been named Pseudomonas creosotensis. It has been completely described by the standard morphological and biochemical tests. Images FIG. 1 PMID:14480909

  13. [A sarcoma-static new species of Pseudomonas, Pseudomonas jinanensis sp. nov].

    PubMed

    Cai, M Y; Lu, D S; Wang, D S; He, Z Z; Wang, J H

    1989-06-01

    A strain of Gram negative bacteria was isolated from the surface soil of Wuying Hill at Jinan, Shandong province with Gause's medium in 1973. It is a strain of antagonistic bacteria for hysterocervicoma, hepatoma and melanoma of mice screened from 2100 strains of bacteria. It is also antagonistic to Staphylococcus aureus, Bacillus subtilis and Micrococcus. It is a Gram negative bacterium with lophotrichous polar flagella. Straight rods in shape or with a little slightly curved rods, 0.5-0.6 X 1-2 microns, randomly arranged, poly-beta-hydroxybutyrate granules are accumulated in cells after 2-5 days cultivation. Water green soluble pigment and green fluorescent pigment are produced. Respiratory metabolism, chemoorganotroph, many carbon-containing organic compounds can be used as carbon sources, such as glucose, trehalose, ethanol, cellulobiose, fucose, arginine and betaine, but propionic acid or tartaric acid is not utilized. Inorganic nitrogen containing compounds can be used ae the sole source of nitrogen. No growth factor is necessary for growth. Gelatin is hydrolyzed. Starch and cellulose are not hydrolyzed. Nitrate is not reduced. Arginine dihydrolase is produced. Levan is produced from sucrose. Growth occurs from 7 degrees C to 37 degrees C and from pH 5.65-8.40. No growth occurs at 40 degrees C and at pH value below 4.86. It can not grow autotrophically with hydrogen. Its G + C contents in DNA is 58.1 mol%. DNA-DNA hybridization experiments reveals a relatedness value of 58.6% between this strain and Ps. fluorescens. The above evidence shows that this strain differs from all species known in Pseudomonas, such as Pseudomonas fluorescens group. Pseudomonas caryophylli, Pseudomonas cepacia, Pseudomonas marginata, Pseudomonas acidovorans, Pseudomonas testosteroni and Pseudomonas delafieldii.(ABSTRACT TRUNCATED AT 250 WORDS)

  14. Antagonistic Effect of Pseudomonas sp. CMI-1 on
Foodborne Pathogenic Listeria monocytogenes.

    PubMed

    Belák, Ágnes; Maráz, Anna

    2015-06-01

    Bacterial isolates derived from food or raw food materials of animal origin were screened for potential antagonistic activity against foodborne pathogenic Listeria monocytogenes. Using the agar spot method, ten out of the 94 tested bacteria showed antilisterial activity. All of the antagonistic isolates identified by sequence analysis as strains of the genus Pseudomonas were able to inhibit the growth of all the examined Listeria species including the ruminal pathogenic L. ivanovii and the opportunistic human pathogenic L. innocua. Pseudomonas sp. CMI-1 had the highest inhibitory effect on the growth of different Listeria strains. Co-culturing studies revealed that the inhibition of L. monocytogenes could not be achieved efficiently. Although the population of the Pseudomonas sp. CMI-1 strain increased by up to 10 orders of magnitude during 2 days of culturing period at 20 °C in the presence of L. monocytogenes, the cell count of the pathogen also increased by approx. 6 orders of magnitude. At the same time, appropriate inhibition of cell-free supernatants generated from 6-day-old cultures of Pseudomonas sp. CMI-1 was observed. The inhibitory compound of this antagonistic strain is presumably a chromopeptide siderophore, whose activity and production can be affected by iron supplementation, and which had an absorption maximum typical of siderophores of fluorescent Pseudomonas species. Production of the antilisterial substance was influenced by the oxygen concentration, as in static cultures the concentration of the siderophore was higher than in shake flask cultures.

  15. Antagonistic Effect of Pseudomonas sp. CMI-1 on
Foodborne Pathogenic Listeria monocytogenes

    PubMed Central

    Maráz, Anna

    2015-01-01

    Summary Bacterial isolates derived from food or raw food materials of animal origin were screened for potential antagonistic activity against foodborne pathogenic Listeria monocytogenes. Using the agar spot method, ten out of the 94 tested bacteria showed antilisterial activity. All of the antagonistic isolates identified by sequence analysis as strains of the genus Pseudomonas were able to inhibit the growth of all the examined Listeria species including the ruminal pathogenic L. ivanovii and the opportunistic human pathogenic L. innocua. Pseudomonas sp. CMI-1 had the highest inhibitory effect on the growth of different Listeria strains. Co-culturing studies revealed that the inhibition of L. monocytogenes could not be achieved efficiently. Although the population of the Pseudomonas sp. CMI-1 strain increased by up to 10 orders of magnitude during 2 days of culturing period at 20 °C in the presence of L. monocytogenes, the cell count of the pathogen also increased by approx. 6 orders of magnitude. At the same time, appropriate inhibition of cell-free supernatants generated from 6-day-old cultures of Pseudomonas sp. CMI-1 was observed. The inhibitory compound of this antagonistic strain is presumably a chromopeptide siderophore, whose activity and production can be affected by iron supplementation, and which had an absorption maximum typical of siderophores of fluorescent Pseudomonas species. Production of the antilisterial substance was influenced by the oxygen concentration, as in static cultures the concentration of the siderophore was higher than in shake flask cultures. PMID:27904352

  16. Genome Sequence of Pseudomonas sp. HUK17, Isolated from Hexachlorocyclohexane-Contaminated Soil

    PubMed Central

    Gasc, Cyrielle; Richard, Jean-Yves

    2016-01-01

    Pseudomonas sp. HUK17 has been isolated from hexachlorocyclohexane (HCH) long-term contaminated soil. The genome of strain HUK17 was sequenced to elucidate its adaptation toward HCH and to evaluate the presence of pesticide degradation pathways. Here, we report the annotated draft genome sequence (~2.6 Mbp) of this strain. PMID:27081140

  17. OXIDATION OF BIPHENYL BY A MULTICOMPONENT ENZYME SYSTEM FROM PSEUDOMONAS SP. STRAIN LB400

    EPA Science Inventory

    Pseudomonas sp. strain LB400 grows on biphenyl as the sole carbon and energy source. This organism also cooxidizes several chlorinated biphenyl congeners. Biphenyl dioxygenase activity in cell extract required addition of NAD(P)H as an electron donor for the conversion of bipheny...

  18. Distribution and survival of Pseudomonas sp. on Italian ryegrass and Curly dock in Georgia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yellow bud, caused by Pseudomonas sp. is an emerging bacterial disease of onion. Polymerase chain reaction (PCR) assay based on the coronafacate ligase (cfl) and HrpZ genes were used to detect initial suspected bacteria on weeds. Growth on an agar medium, ability to cause a hypersensitive response i...

  19. Reduction of Selenite to Elemental Red Selenium by Pseudomonas sp. strain CA5

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A Pseudomonas sp. that may be useful in bioremediation projects was isolated from soil. The strain is of potential value because it reduces selenite to elemental red selenium and is unusual in that it was resistant to high concentrations of both selenate and selenite. Cell of the strain removed 1....

  20. Draft Genome Sequence of Pseudomonas sp. Strain CCA1, Isolated from Leaf Soil

    PubMed Central

    Kimura, Zen-ichiro; Hoshino, Tamotsu

    2016-01-01

    Pseudomonas sp. strain CCA1 was isolated from leaf soil collected in Higashi-Hiroshima City in Hiroshima Prefecture, Japan. Here, we present a draft genome sequence of this strain. The genome consists of 24 contigs for a total of 6,993,992 bp, 8,917 predicted coding sequences, and a GC content of 67.2%. PMID:27932657

  1. Draft Genome Sequence of Antarctic Pseudomonas sp. Strain KG01 with Full Potential for Biotechnological Applications

    PubMed Central

    Pavlov, María S.; Lira, Felipe; Martínez, José L.; Olivares, Jorge

    2015-01-01

    We report here the draft genome sequence of a free-living psychrotolerant, Pseudomonas sp. strain KG01, isolated from an Antarctic soil sample and displaying interesting antimicrobial and surfactant activities. The sequence is 6.3 Mb long and includes 5,648 predicted-coding sequences. PMID:26294625

  2. Draft Genome Sequence of Antarctic Pseudomonas sp. Strain KG01 with Full Potential for Biotechnological Applications.

    PubMed

    Pavlov, María S; Lira, Felipe; Martínez, José L; Olivares, Jorge; Marshall, Sergio H

    2015-08-20

    We report here the draft genome sequence of a free-living psychrotolerant, Pseudomonas sp. strain KG01, isolated from an Antarctic soil sample and displaying interesting antimicrobial and surfactant activities. The sequence is 6.3 Mb long and includes 5,648 predicted-coding sequences.

  3. Transformation of carbon tetrachloride via sulfur and oxygen substitution by Pseudomonas sp. strain KC.

    PubMed Central

    Lewis, T A; Crawford, R L

    1995-01-01

    Pseudomonas sp. strain KC transforms carbon tetrachloride into carbon dioxide and nonvolatile products, without chloroform as an intermediate. To define the pathway for hydrolysis, nonvolatile products were analyzed. Condensation products containing the carbon atom of carbon tetrachloride as carbonyl and thioxo moieties were identified, indicating the intermediacy of phosgene and thiophosgene in the pathway. PMID:7721711

  4. Degradation of 4-chloro-3-nitrophenol via a novel intermediate, 4-chlororesorcinol by Pseudomonas sp. JHN

    NASA Astrophysics Data System (ADS)

    Arora, Pankaj Kumar; Srivastava, Alok; Singh, Vijay Pal

    2014-03-01

    A 4-chloro-3-nitrophenol (4C3NP)-mineralizing bacterium, Pseudomonas sp. JHN was isolated from a waste water sample collected from a chemically-contaminated area, India by an enrichment method. Pseudomonas sp. JHN utilized 4C3NP as a sole carbon and energy source and degraded it with the release of stoichiometric amounts of chloride and nitrite ions. Gas chromatography and gas chromatography-mass spectrometry detected 4-chlororesorcinol as a major metabolite of the 4C3NP degradation pathway. Inhibition studies using 2,2'-dipyridyl showed that 4-chlororesorcinol is a terminal aromatic compound in the degradation pathway of 4C3NP. The activity for 4C3NP-monooxygenase was detected in the crude extracts of the 4C3NP-induced JHN cells that confirmed the formation of 4-chlororesorcinol from 4C3NP. The capillary assay showed that Pseudomonas sp. JHN exhibited chemotaxis toward 4C3NP. The bioremediation capability of Pseudomonas sp. JHN was monitored to carry out the microcosm experiments using sterile and non-sterile soils spiked with 4C3NP. Strain JHN degraded 4C3NP in sterile and non-sterile soil with same degradation rates. This is the first report of (i) bacterial degradation and bioremediation of 4C3NP, (ii) formation of 4-chlororesorcinol in the degradation pathway of 4C3NP, (iii) bacterial chemotaxis toward 4C3NP.

  5. Pseudomonas frederiksbergensis sp. nov., isolated from soil at a coal gasification site.

    PubMed

    Andersen, S M; Johnsen, K; Sørensen, J; Nielsen, P; Jacobsen, C S

    2000-11-01

    Phenotypic and genotypic characterization indicated that a group of 29 closely related phenanthrene-degrading bacteria from a coal gasification site in Frederiksberg, Copenhagen, Denmark, belonged to the genus Pseudomonas. The strains were isolated at two sampling occasions 2 years apart. The isolates were phenotypically different from any known species of the genus Pseudomonas and were therefore subject to further identification. Colonies were smooth and pale yellowish and did not produce pigments fluorescent in UV light when grown on King's B agar. Cells were rod-shaped, approximately 0.5-0.8 x 1.5-3.0 microm, and grew at 4 and 30 degrees C, but not 37 degrees C. The bacteria were oxidase- and catalase-positive, accumulated poly-beta-hydroxybutyrate and denitrified, but did not utilize D-xylose. The mean G+C content was 59.6 mol%. Phenotypic data and 16S rDNA sequence data information for Pseudomonas amygdali and Pseudomonas corrugata, and 16S rDNA sequence data for Pseudomonas chlororaphis and Pseudomonas syringae showed close relationships to these strains. However, DNA-DNA hybridization data showed that the isolates belong to a new species, for which the name Pseudomonas frederiksbergensis sp. nov. is proposed. The type strain is JAJ28T (DSM 13022T).

  6. Pseudomonas sagittaria sp. nov., a siderophore-producing bacterium isolated from oil-contaminated soil.

    PubMed

    Lin, Shih-Yao; Hameed, Asif; Liu, You-Cheng; Hsu, Yi-Han; Lai, Wei-An; Chen, Wen-Ming; Shen, Fo-Ting; Young, Chiu-Chung

    2013-07-01

    An aerobic, Gram-stain-negative, rod-shaped bacterium with a single polar flagellum, designated CC-OPY-1(T), was isolated from an oil-contaminated site in Taiwan. CC-OPY-1(T) produces siderophores, and can grow at temperatures of 25-37 °C and pH 5.0-9.0 and tolerate <5 % (w/v) NaCl. The 16S rRNA gene sequence analysis of CC-OPY-1(T) showed high pairwise sequence similarity to Pseudomonas alcaligenes BCRC 11893(T) (97.1 %), Pseudomonas. alcaliphila DSM 17744(T) (97.1 %), Pseudomonas tuomuerensis JCM 14085(T) (97.1 %), Pseudomonas toyotomiensis JCM 15604(T) (96.9 %) and lower sequence similarity to remaining species of the genus Pseudomonas. The phylogenetic trees reconstructed based on gyrB and rpoB gene sequences supported the classification of CC-OPY-1(T) as a novel member of the genus Pseudomonas. The predominant quinone system of strain CC-OPY-1T was ubiquinone (Q-9) and the DNA G+C content was 68.4 ± 0.3 mol%. The major fatty acids were C12 : 0, C16 : 0, C17 : 0 cyclo and summed features 3 and 8 consisting of C16 : 1ω7c/C16 : 1ω6c and C18 : 1ω7c/C18 : 1ω6c, respectively. The major polar lipids were phosphatidylethanolamine (PE), phosphatidylglycerol (PG), diphosphatidylglycerol (DPG), phosphatidylcholine (PC) and two unknown phospholipids (PL1-2). Due to distinct phylogenetic, phenotypic and chemotaxonomic features, CC-OPY-1(T) is proposed to represent a novel species within the genus Pseudomonas for which the name Pseudomonas sagittaria sp. nov. is proposed. The type strain is CC-OPY-1(T) ( = BCRC 80399(T) = JCM 18195(T)).

  7. Pseudomonas hunanensis sp. nov., isolated from soil subjected to long-term manganese pollution.

    PubMed

    Gao, Jian; Li, Bai-Yuan; Wang, Hai-Hua; Liu, Zhi-Qiang

    2014-07-01

    A Gram-negative, polar flagella, rod-shaped bacterium LV (T) was isolated from a soil sample subjected to long-term manganese pollution in Hunan Province, China. Cells grow optimally on Luria-Bertani agar medium at 30 °C in the presence of 0-5.0 % (w/v) NaCl and pH 7-8. 16S rRNA gene sequence analysis revealed that strain LV (T) belonged to the genus Pseudomonas, with sequence similarity values of 98.6, 98.2, 98.7, and 97.3 % to Pseudomonas monteilii BCRC 17520 (T) , Pseudomonas putida BCRC 10459 (T) , Pseudomonas plecoglossicida BCRC 17517 (T) , and Pseudomonas asplenii BCRC 17131 (T) , respectively. The level of DNA-DNA relatedness between the five strains was <30 %. The DNA G+C content of strain LV (T) is 68.8 mol%. Chemotaxonomic data revealed that the strain LV(T) possesses ubiquinone Q-9. The polar lipid profile of strain LV (T) contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, and phosphatidylethanolamine. The major cellular fatty acids present are C10:03-OH (12.33 %), C16:0 (23.99 %), summed feature 3(C16:1ω7c and/or C16:1ω6c), and summed feature 8(C18:1 ω7c and C18:1 ω6c). Based on the genotypic, chemotaxonomic and phenotypic data, strain LV (T) is distinguishable from related members of the genus Pseudomonas. Thus, strain LV (T) represents a novel species of the genus Pseudomonas, for which the name Pseudomonas hunanensis sp. nov. is proposed. The type strain is LV (T) (=CICC 10558(T) = NCCB 100446(T)).

  8. Utilization of Phenylpropanoids by Newly Isolated Bacterium Pseudomonas sp. TRMK1.

    PubMed

    T R, Monisha; I, Mukram; B, Kirankumar; Reddy, Pooja V; Nayak, Anand S; Karegoudar, T B

    2017-01-25

    A bacterium Pseudomonas sp. TRMK1 capable of utilizing various phenylpropanoids was isolated from agro-industrial waste by enrichment culture technique. It is gram-negative, motile, aerobic, and able to utilize three different phenolic acids such as p-coumaric, ferulic, and caffeic acids at concentrations of 5, 10, and 15 mM in 18 h of incubation. The residual concentration of phenolic acids was analyzed by HPLC. The catabolic pathway of p-coumaric, ferulic, and caffeic acids is suggested based on the characterization of metabolic intermediates by GC, GC-HRMS, and different enzymatic assays. Further, Pseudomonas sp. TRMK1 utilizes a wide range of mixture of phenolic acids present in the synthetic effluent.

  9. Secondary substrate utilization of methylene chloride by an isolated strain of Pseudomonas sp.

    PubMed Central

    LaPat-Polasko, L T; McCarty, P L; Zehnder, A J

    1984-01-01

    Secondary substrate utilization of methylene chloride was analyzed by using Pseudomonas sp. strain LP. Both batch and continuously fed reactors demonstrated that this strain was capable of simultaneously consuming two substrates at different concentrations: the primary substrate at the higher concentration (milligrams per liter) and the secondary substrate at the lower concentration (micrograms per liter). The rate of methylene chloride utilization at trace concentrations was greater in the presence of the primary substrate, acetate, than without it. However, when the substrate roles were changed, the acetate secondary substrate utilization rate was less when methylene chloride was present. Thus, substrate interactions are important in the kinetics of secondary substrate utilization. Pseudomonas sp. strain LP showed a preference toward degrading methylene chloride over acetate, whether it was the primary or secondary substrate, providing it was below an inhibitory concentration of ca. 10 mg/liter. PMID:6721491

  10. Pseudomonas glareae sp. nov., a marine sediment-derived bacterium with antagonistic activity.

    PubMed

    Romanenko, Lyudmila A; Tanaka, Naoto; Svetashev, Vassilii I; Mikhailov, Valery V

    2015-06-01

    An aerobic, Gram-negative, motile, rod-shaped bacterium designated KMM 9500(T) was isolated from a sediment sample collected from the Sea of Japan seashore. Comparative 16S rRNA gene sequence analysis affiliated strain KMM 9500(T) to the genus Pseudomonas as a distinct subline clustered with Pseudomonas marincola KMM 3042(T) and Pseudomonas segetis KCTC 12331(T) sharing the highest similarities of 98 and 97.9 %, respectively. Strain KMM 9500(T) was characterized by mainly possessing ubiquinone Q-9, and by the predominance of C18:1 ω7c, C16:1 ω7c, and C16:0 followed by C12:0 in its fatty acid profile. Polar lipids consisted of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, an unknown aminophospholipid, and unknown phospholipids. Strain KMM 9500(T) was found to inhibit growth of Gram-negative and Gram-positive indicatory microorganisms. Based on the phylogenetic analysis and distinctive phenotypic characteristics, strain 9500(T) is concluded to represent a novel species of the genus Pseudomonas, for which the name Pseudomonas glareae sp. nov. is proposed. The type strain of the species is strain KMM 9500(T) (=NRIC 0939(T)).

  11. New emulsifying and cryoprotective exopolysaccharide from Antarctic Pseudomonas sp. ID1.

    PubMed

    Carrión, Ornella; Delgado, Lidia; Mercade, Elena

    2015-03-06

    Pseudomonas sp. ID1 is a cold-adapted bacterium isolated from a marine sediment sample collected from South Shetland Islands (Antarctica) that is noted for the highly mucous appearance of its colonies. In this work, we have characterized an exopolysaccharide (EPS) produced by this strain, which is mainly composed of glucose, galactose and fucose, and has a molecular mass higher than 2×10(6) Da. We have also studied its potential biotechnological applications as an emulsifier and cryoprotectant agent. The EPS emulsifying activity against different food and cosmetic oils was much higher than commercial gums such as xanthan gum and arabic gum, and surfarctants such as Span 20. It formed highly stable emulsions against the cosmetic oil cetiol V, exhibiting pseudoplastic flow behavior, low thixotrophy and yield stress. The EPS of Pseudomonas sp. ID1 conferred significant cryoprotection for the strain itself as well as for other bacteria, including Escherichia coli, suggesting a universal cryoprotectant role. The cryoprotective activity of the EPS showed a clear dose-response relation at -20 °C and -80 °C and was significantly higher than that observed for the membrane stabilizer fetal bovine serum (FBS). These properties make the EPS of Pseudomonas sp. ID1 a promising alternative to commercial polysaccharides as an emulsifier and cryoprotectant agent for food, pharmaceutical and cosmetic industries.

  12. Biodegradation of Methyl tert-Butyl Ether by Co-Metabolism with a Pseudomonas sp. Strain

    PubMed Central

    Li, Shanshan; Wang, Shan; Yan, Wei

    2016-01-01

    Co-metabolic bioremediation is supposed to be an impressive and promising approach in the elimination technology of methyl tert-butyl ether (MTBE), which was found to be a common pollutant worldwide in the ground or underground water in recent years. In this paper, bacterial strain DZ13 (which can co-metabolically degrade MTBE) was isolated and named as Pseudomonas sp. DZ13 based on the result of 16S rRNA gene sequencing analysis. Strain DZ13 could grow on n-alkanes (C5-C8), accompanied with the co-metabolic degradation of MTBE. Diverse n-alkanes with different carbon number showed a significant influence on the degradation rate of MTBE and accumulation of tert-butyl alcohol (TBA). When Pseudomonas sp. DZ13 co-metabolically degraded MTBE with n-pentane as the growth substrate, a higher MTBE-degrading rate (Vmax = 38.1 nmol/min/mgprotein, Ks = 6.8 mmol/L) and lower TBA-accumulation was observed. In the continuous degradation experiment, the removal efficiency of MTBE by Pseudomonas sp. Strain DZ13 did not show an obvious decrease after five times of continuous addition. PMID:27608032

  13. Kinetics of growth and caffeine demethylase production of Pseudomonas sp. in bioreactor.

    PubMed

    Gummadi, Sathyanarayana N; Santhosh, Devarai

    2010-09-01

    The effect of various initial caffeine concentrations on growth and caffeine demethylase production by Pseudomonas sp. was studied in bioreactor. At initial concentration of 6.5 g l(-1) caffeine, Pseudomonas sp. showed a maximum specific growth rate of 0.2 h(-1), maximum degradation rate of 1.1 g h(-1), and caffeine demethylase activity of 18,762 U g CDW(-1) (CDW: cell dry weight). Caffeine degradation rate was 25 times higher in bioreactor than in shake flask. For the first time, we show highest degradation of 75 g caffeine (initial concentration 20 g l(-1)) in 120 h, suggesting that the tested strain has potential for successful bioprocess for caffeine degradation. Growth kinetics showed substrate inhibition phenomenon. Various substrate inhibition models were fitted to the kinetic data, amongst which the double-exponential (R(2) = 0.94), Luong (R(2) = 0.92), and Yano and Koga 2 (R(2) = 0.94) models were found to be the best. The Luedeking-Piret model showed that caffeine demethylase production kinetics was growth related. This is the first report on production of high levels of caffeine demethylase in batch bioreactor with faster degradation rate and high tolerance to caffeine, hence clearly suggesting that Pseudomonas sp. used in this study is a potential biocatalyst for industrial decaffeination.

  14. Isolation and Characterization of a Pseudomonas sp. That Mineralizes the s-Triazine Herbicide Atrazine

    PubMed Central

    Mandelbaum, R. T.; Allan, D. L.; Wackett, L. P.

    1995-01-01

    A bacterium that was capable of metabolizing atrazine at very high concentrations (>1,000 ppm) was isolated from a herbicide spill site. The organism was differentiated by observing clearing zones on indicator agar plates containing 1,000 ppm atrazine. Detailed taxonomic studies identified the organism as a Pseudomonas sp., designated ADP, that was dissimilar to currently known species. Pseudomonas sp. strain ADP metabolized atrazine as its sole nitrogen source. Nongrowing suspended cells also metabolized atrazine rapidly; for example, 9 x 10(sup9) cells per ml degraded 100 ppm of atrazine in 90 min. Atrazine was metabolized to hydroxyatrazine, polar metabolites, and carbon dioxide. When uniformly ring-labeled [(sup14)C]atrazine was used, 80% of the radioactivity was liberated as (sup14)CO(inf2). These data indicated the triazine ring was completely mineralized. The isolation and characterization of Pseudomonas sp. strain ADP may contribute to efforts on atrazine bioremediation, particularly in environments containing very high pesticide levels. PMID:16534995

  15. Pseudomonas endophytica sp. nov., isolated from stem tissue of Solanum tuberosum L. in Spain.

    PubMed

    Ramírez-Bahena, Martha-Helena; Cuesta, Maria José; Tejedor, Carmen; Igual, José Mariano; Fernández-Pascual, Mercedes; Peix, Álvaro

    2015-07-01

    A bacterial strain named BSTT44(T) was isolated in the course of a study of endophytic bacteria occurring in stems and roots of potato growing in a soil from Salamanca, Spain. The 16S rRNA gene sequence had 99.7% identity with respect to that of its closest relative, Pseudomonas psychrophila E-3T, and the next most closely related type strains were those of Pseudomonas fragi, with 99.6% similarity, Pseudomonas deceptionensis, with 99.2% similarity, and Pseudomonas lundensis, with 99.0% similarity; these results indicate that BSTT44(T) should be classified within the genus Pseudomonas. Analysis of the housekeeping genes rpoB, rpoD and gyrB confirmed its phylogenetic affiliation and showed identities lower than 92% in all cases with respect to the above-mentioned closest relatives. Cells of the strain bore one polar-subpolar flagellum. The respiratory quinone was Q-9.The major fatty acids were C16:0, C18:1ω7c and summed feature 3 (C16:1ω7c and/or C16:1ω6c). The strain was oxidase-, catalase- and urease-positive and the arginine dihydrolase system was present, but tests for nitrate reduction, β-galactosidase production and aesculin hydrolysis were negative. It could grow at 35 °C and at pH 5-9.The DNA G+C content was 60.2 mol%. DNA-DNA hybridization results showed less than 48% relatedness with respect to the type strains of the four most closely related species. Therefore, the combined results of genotypic, phenotypic and chemotaxonomic analyses support the classification of strain BSTT44 into a novel species of the genus Pseudomonas, for which the name Pseudomonas endophytica sp. nov. is proposed. The type strain is BSTT44(T) ( = LMG 28456(T) = CECT 8691(T)).

  16. Biodegradation of 4-nitrotoluene by Pseudomonas sp. strain 4NT.

    PubMed Central

    Haigler, B E; Spain, J C

    1993-01-01

    A strain of Pseudomonas spp. was isolated from nitrobenzene-contaminated soil on 4-nitrotoluene as the sole source of carbon, nitrogen, and energy. The organism also grew on 4-nitrobenzaldehyde, and 4-nitrobenzoate. 4-Nitrobenzoate and ammonia were detected in the culture fluid of glucose-grown cells after induction with 4-nitrotoluene. Washed suspensions of 4-nitrotoluene- or 4-nitrobenzoate-grown cells oxidized 4-nitrotoluene, 4-nitrobenzaldehyde, 4-nitrobenzyl alcohol, and protocatechuate. Extracts from induced cells contained 4-nitrobenzaldehyde dehydrogenase, 4-nitrobenzyl alcohol dehydrogenase, and protocatechuate 4,5-dioxygenase activities. Under anaerobic conditions, cell extracts converted 4-nitrobenzoate or 4-hydroxylaminobenzoate to protocatechuate. Conversion of 4-nitrobenzoate to protocatechuate required NADPH. These results indicate that 4-nitrotoluene was degraded by an initial oxidation of the methyl group to form 4-nitrobenzyl alcohol, which was converted to 4-nitrobenzoate via 4-nitrobenzaldehyde. The 4-nitrobenzoate was reduced to 4-hydroxylaminobenzoate, which was converted to protocatechuate. A protocatechuate 4,5-dioxygenase catalyzed meta-ring fission of the protocatechuate. The detection of 4-nitrobenzaldehyde and 4-nitrobenzyl alcohol dehydrogenase and 4-nitrotoluene oxygenase activities in 4-nitrobenzoate-grown cells suggests that 4-nitrobenzoate is an inducer of the 4-nitrotoluene degradative pathway. PMID:8357257

  17. Enzymes responsible for chlorate reduction by Pseudomonas sp. are different from those used for perchlorate reduction by Azospira sp.

    PubMed

    Steinberg, Lisa M; Trimble, John J; Logan, Bruce E

    2005-06-15

    Pseudomonas sp. PDA is an unusual bacterium due to its ability to respire using chlorate under aerobic conditions. The chlorate reductase produced by PDA was shown to be intrinsically different from the enzyme responsible for chlorate and perchlorate [(per)chlorate] reduction produced by Azospira sp. KJ based on subunit composition and other enzyme properties. The perchlorate reductase from strain KJ appeared to have two subunits (100 and 40 kDa) while the chlorate reductase from PDA had three subunits (60, 48, and 27 kDa). N-terminal amino acid sequencing of the 100 kDa protein from strain KJ showed a 77% similarity with the perchlorate reductase alpha subunit from another perchlorate-respiring bacterium, Dechloromonas agitata, while the N-terminus amino acid sequence of the 60 kDa protein from strain PDA did not show a similarity to previously isolated chlorate or perchlorate reductases.

  18. The Complete Genome Sequence of the Plant Growth-Promoting Bacterium Pseudomonas sp. UW4

    PubMed Central

    Duan, Jin; Jiang, Wei; Cheng, Zhenyu; Heikkila, John J.; Glick, Bernard R.

    2013-01-01

    The plant growth-promoting bacterium (PGPB) Pseudomonas sp. UW4, previously isolated from the rhizosphere of common reeds growing on the campus of the University of Waterloo, promotes plant growth in the presence of different environmental stresses, such as flooding, high concentrations of salt, cold, heavy metals, drought and phytopathogens. In this work, the genome sequence of UW4 was obtained by pyrosequencing and the gaps between the contigs were closed by directed PCR. The P. sp. UW4 genome contains a single circular chromosome that is 6,183,388 bp with a 60.05% G+C content. The bacterial genome contains 5,423 predicted protein-coding sequences that occupy 87.2% of the genome. Nineteen genomic islands (GIs) were predicted and thirty one complete putative insertion sequences were identified. Genes potentially involved in plant growth promotion such as indole-3-acetic acid (IAA) biosynthesis, trehalose production, siderophore production, acetoin synthesis, and phosphate solubilization were determined. Moreover, genes that contribute to the environmental fitness of UW4 were also observed including genes responsible for heavy metal resistance such as nickel, copper, cadmium, zinc, molybdate, cobalt, arsenate, and chromate. Whole-genome comparison with other completely sequenced Pseudomonas strains and phylogeny of four concatenated “housekeeping” genes (16S rRNA, gyrB, rpoB and rpoD) of 128 Pseudomonas strains revealed that UW4 belongs to the fluorescens group, jessenii subgroup. PMID:23516524

  19. Description of Pseudomonas gregormendelii sp. nov., a Novel Psychrotrophic Bacterium from James Ross Island, Antarctica.

    PubMed

    Kosina, Marcel; Švec, Pavel; Černohlávková, Jitka; Barták, Miloš; Snopková, Kateřina; De Vos, Paul; Sedláček, Ivo

    2016-07-01

    During the microbiological research performed within the scope of activities of Czech expeditions based at the Johann Gregor Mendel Station at James Ross Island, Antarctica, two psychrotrophic gram-stain negative non-fluorescent strains CCM 8506T and CCM 8507 from soil were extensively characterized using genotypic and phenotypic methods. Initial characterization using ribotyping with HindIII restriction endonuclease and phenotyping implies that both isolates belong to a single Pseudomonas species. Sequencing of rrs, rpoB, rpoD and glnA genes of strain CCM 8506(T) confirmed affiliation of investigated strains within the genus Pseudomonas. Further investigation using automated ribotyping with EcoRI (RiboPrinter(®) Microbial Characterisation System), whole-cell protein profiling using the Agilent 2100 Bioanalyzer system, extensive biochemical testing and DNA-DNA hybridization experiments confirmed that both investigated strains are members of a single taxon which is clearly separated from all hitherto described Pseudomonas spp. Based on all findings, we describe a novel species Pseudomonas gregormendelii sp. nov. with the type strain CCM 8506(T) (=LMG 28632T).

  20. Discovery of a cutinase-producing Pseudomonas sp. cohabiting with an apparently nitrogen-fixing Corynebacterium sp. in the phyllosphere.

    PubMed Central

    Sebastian, J; Chandra, A K; Kolattukudy, P E

    1987-01-01

    A phyllospheric bacterial culture, previously reported to partially replace nitrogen fertilizer (B. R. Patti and A. K. Chandra, Plant Soil 61:419-427, 1981) was found to contain a fluorescent pseudomonas which was identified as Pseudomonas putida and a Corynebacterium sp. The P. putida isolate was found to produce an extracellular cutinase when grown in a medium containing cutin, the polyester structural component of plant cuticle. The Corynebacterium sp. grew on nitrogen-free medium but could not produce cutinase under any induction conditions tested, whereas P. putida could not grow on nitrogen-free medium. When cocultured with the nitrogen-fixing Corynebacterium sp., the P. putida isolate grew in a nitrogen-free medium, suggesting that the former provided fixed N2 for the latter. These results suggest that the two species coexist on the plant surface, with one providing carbon and the other providing reduced nitrogen for their growth. The presence of cutin in the medium induced cutinase production by P. putida. However, unlike the previously studied fungal systems, cutin hydrolysate did not induce cutinase. Thin-layer chromatographic analysis of the products released from labeled apple fruit cutin showed that the extracellular enzyme released all classes of cutin monomers. This enzyme also catalyzed hydrolysis of the model ester substrates, p-nitrophenyl esters of fatty acids, and optimal conditions were determined for a spectrophotometric assay with p-nitrophenyl butyrate as the substrate. It did not hydrolyze triacyl glycerols, indicating that the cutinase activity was not due to a nonspecific lipase. It showed a broad pH optimum between 8.0 and 10.5 with 3H-labeled apple cutin as the substrate.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3793714

  1. Interaction between fish spoilage bacteria Pseudomonas sp. and Shewanella putrefaciens in fish extracts and on fish tissue.

    PubMed

    Gram, L; Melchiorsen, J

    1996-06-01

    The interaction between fish spoilage bacteria, Pseudomonas sp. and Shewanella putrefaciens, was investigated using fish extract and fish tissue as model systems. Isolates of Pseudomonas that produced iron chelators, siderophores, inhibited growth of S. putrefaciens in a fish-extract-agar diffusion assay but no, or only weak, antagonistic activity was seen when the medium was supplemented with iron. Sterile-filtered supernatant fluid from a siderophore-producing Pseudomonas grown in fish extract was inhibitory to S. putrefaciens if the number of Psudomonas was above 10(8) cfu ml-1. In contrast, supernatant fluids from siderophore-negative Pseudomonas isolates did not inhibit growth of S. putrefaciens. The inhibitory effect was, except for one strain of Pseudomonas, not seen in supernatant fluids from iron-enriched cultures of Pseudomonas sp. Finally, siderophore-producing Pseudomonas sp. lowered the maximum cell level of S. putrefaciens 1-2 log units from 10(9) to 10(10) cfu g-1 when the strains were grown on fish muscle blocks at 0 degrees C but the growth rate of S. putrefaciens was not affected.

  2. Conversion of the Pseudomonas aeruginosa Quinolone Signal and Related Alkylhydroxyquinolines by Rhodococcus sp. Strain BG43

    PubMed Central

    Müller, Christine; Birmes, Franziska S.; Niewerth, Heiko

    2014-01-01

    A bacterial strain, which based on the sequences of its 16S rRNA, gyrB, catA, and qsdA genes, was identified as a Rhodococcus sp. closely related to Rhodococcus erythropolis, was isolated from soil by enrichment on the Pseudomonas quinolone signal [PQS; 2-heptyl-3-hydroxy-4(1H)-quinolone], a quorum sensing signal employed by the opportunistic pathogen Pseudomonas aeruginosa. The isolate, termed Rhodococcus sp. strain BG43, cometabolically degraded PQS and its biosynthetic precursor 2-heptyl-4(1H)-quinolone (HHQ) to anthranilic acid. HHQ degradation was accompanied by transient formation of PQS, and HHQ hydroxylation by cell extracts required NADH, indicating that strain BG43 has a HHQ monooxygenase isofunctional to the biosynthetic enzyme PqsH of P. aeruginosa. The enzymes catalyzing HHQ hydroxylation and PQS degradation were inducible by PQS, suggesting a specific pathway. Remarkably, Rhodococcus sp. BG43 is also capable of transforming 2-heptyl-4-hydroxyquinoline-N-oxide to PQS. It thus converts an antibacterial secondary metabolite of P. aeruginosa to a quorum sensing signal molecule. PMID:25239889

  3. Conversion of the Pseudomonas aeruginosa Quinolone Signal and Related Alkylhydroxyquinolines by Rhodococcus sp. Strain BG43.

    PubMed

    Müller, Christine; Birmes, Franziska S; Niewerth, Heiko; Fetzner, Susanne

    2014-12-01

    A bacterial strain, which based on the sequences of its 16S rRNA, gyrB, catA, and qsdA genes, was identified as a Rhodococcus sp. closely related to Rhodococcus erythropolis, was isolated from soil by enrichment on the Pseudomonas quinolone signal [PQS; 2-heptyl-3-hydroxy-4(1H)-quinolone], a quorum sensing signal employed by the opportunistic pathogen Pseudomonas aeruginosa. The isolate, termed Rhodococcus sp. strain BG43, cometabolically degraded PQS and its biosynthetic precursor 2-heptyl-4(1H)-quinolone (HHQ) to anthranilic acid. HHQ degradation was accompanied by transient formation of PQS, and HHQ hydroxylation by cell extracts required NADH, indicating that strain BG43 has a HHQ monooxygenase isofunctional to the biosynthetic enzyme PqsH of P. aeruginosa. The enzymes catalyzing HHQ hydroxylation and PQS degradation were inducible by PQS, suggesting a specific pathway. Remarkably, Rhodococcus sp. BG43 is also capable of transforming 2-heptyl-4-hydroxyquinoline-N-oxide to PQS. It thus converts an antibacterial secondary metabolite of P. aeruginosa to a quorum sensing signal molecule.

  4. Localization of polyamine enhancement of protein synthesis to subcellular components of Escherichia coli and Pseudomonas sp. strain Kim.

    PubMed Central

    Rosano, C L; Bunce, S C; Hurwitz, C

    1983-01-01

    At 5 mM Mg2+, spermidine stimulation of polyphenylalanine synthesis by cell-free extracts of Escherichia coli was found to be about 30 times greater than that by extracts of Pseudomonas sp. strain Kim, a unique organism which lacks detectable levels of spermidine. By means of reconstitution experiments, the target of spermidine stimulation was localized to the protein fraction of the highspeed supernatant component (S-100) of E. coli and was absent from, or deficient in, the S-100 fraction of Pseudomonas sp. strain Kim. The spermidine stimulation did not appear to be due to the presence in the E. coli S-100 fraction of ribosomal protein S1, elongation factors, or E. coli aminoacyl-tRNA synthetases. The failure to observe spermidine stimulation by the Pseudomonas sp. strain Kim S-100 fraction was also not due to a spermidine-enhanced polyuridylic acid degradation. The synthesis of polyphenylalanine by Pseudomonas sp. strain Kim extracts was stimulated by putrescine and by S-(+)-2-hydroxyputrescine to a greater degree than was synthesis by E. coli extracts. The enhancement by putrescine and by S-(+)-2-hydroxyputrescine with Pseudomonas sp. strain Kim extracts was found to be due to effects on its ribosomes. PMID:6336736

  5. Pseudomonas toyotomiensis sp. nov., a psychrotolerant facultative alkaliphile that utilizes hydrocarbons.

    PubMed

    Hirota, Kikue; Yamahira, Keiko; Nakajima, Kenji; Nodasaka, Yoshinobu; Okuyama, Hidetoshi; Yumoto, Isao

    2011-08-01

    A psychrotolerant, facultatively alkaliphilic strain, HT-3(T), was isolated from a sample of soil immersed in hot-spring water containing hydrocarbons in Toyotomi, Hokkaido, Japan. 16S rRNA gene sequence-based phylogeny suggested that strain HT-3(T) is a member of the genus Pseudomonas and belongs to the Pseudomonas oleovorans group. Cells of the isolate were Gram-negative, aerobic, straight rods, motile by a single polar flagellum. The strain grew at 4-42 °C, with optimum growth at 35 °C at pH 7, and at pH 6-10. It hydrolysed Tweens 20, 40, 60 and 80, but not casein, gelatin, starch or DNA. Its major isoprenoid quinone was ubiquinone-9 (Q-9) and the DNA G+C content was 65.1 mol%. The whole-cell fatty acid profile consisted mainly of C(16 : 0), C(16 : 1)ω9c and C(18 : 1)ω9c. Phylogenetic analyses based on gyrB, rpoB and rpoD sequences revealed that the isolate could be discriminated from Pseudomonas species that exhibited more than 97 % 16S rRNA gene sequence similarity and phylogenetic neighbours belonging to the P. oleovorans group including the closest relative of the isolate, Pseudomonas alcaliphila. DNA-DNA hybridization with P. alcaliphila AL15-21(T) revealed 51 ± 5 % relatedness. Owing to differences in phenotypic properties and phylogenetic analyses based on multilocus gene sequence analysis and DNA-DNA relatedness data, the isolate merits classification in a novel species, for which the name Pseudomonas toyotomiensis sp. nov. is proposed. The type strain is HT-3(T) ( = JCM 15604(T)  = NCIMB 14511(T)).

  6. Pseudomonas sp. BUP6, a novel isolate from Malabari goat produces an efficient rhamnolipid type biosurfactant.

    PubMed

    Priji, Prakasan; Sajith, Sreedharan; Unni, Kizhakkepowathial Nair; Anderson, Robin C; Benjamin, Sailas

    2017-01-01

    This study describes the characteristics of a biosurfactant produced by Pseudomonas sp. BUP6, a rumen bacterium, and optimization of parameters required for its production. Initial screening of five parameters (pH, temperature, agitation, incubation, and substrate concentration) was carried out employing Plackett-Burman design, which reduced the number of parameters to 3 (pH, temperature, and incubation) according to their significance on the yield of biosurfactant. A suitable statistical model for the production of biosurfactant by Pseudomonas sp. BUP6 was established according to Box-Behnken design, which resulted in 11% increase (at pH 7, 35 °C, incubation 75 h) in the yield (2070 mg L(-1) ) of biosurfactant. The biosurfactant was found stable at a wide range of pH (3-9) with 48 mg L(-1) critical micelle concentration; and maintained over 90% of its emulsification ability even after boiling and in presence of sodium chloride (0.5%). The highest cell hydrophobicity (37%) and emulsification (69%) indices were determined with groundnut oil and kerosene, respectively. The biosurfactant was found to inhibit the growth and adhesion of E. coli and S. aureus significantly. From the phytotoxicity studies, the biosurfactant did not show any adverse effect on the germinating seeds of rice and green gram. The structural characterization of biosurfactant employing orcinol method, thin layer chromatography and FT-IR indicated that it is a rhamnolipid (glycolipid). Thus, Pseudomonas sp. BUP6, a novel isolate from Malabari goat is demonstrated as a producer of an efficient rhamnolipid type biosurfactant suitable for application in various industries.

  7. X-ray crystal structure of a malonate-semialdehyde dehydrogenase from Pseudomonas sp. strain AAC.

    PubMed

    Wilding, Matthew; Scott, Colin; Peat, Thomas S; Newman, Janet

    2017-01-01

    The NAD-dependent malonate-semialdehyde dehydrogenase KES23460 from Pseudomonas sp. strain AAC makes up half of a bicistronic operon responsible for β-alanine catabolism to produce acetyl-CoA. The KES23460 protein has been heterologously expressed, purified and used to generate crystals suitable for X-ray diffraction studies. The crystals belonged to space group P212121 and diffracted X-rays to beyond 3 Å resolution using the microfocus beamline of the Australian Synchrotron. The structure was solved using molecular replacement, with a monomer from PDB entry 4zz7 as the search model.

  8. Arsenic redox transformation by Pseudomonas sp. HN-2 isolated from arsenic-contaminated soil in Hunan, China.

    PubMed

    Zhang, Zhennan; Yin, Naiyi; Cai, Xiaolin; Wang, Zhenzhou; Cui, Yanshan

    2016-09-01

    A mesophilic, Gram-negative, arsenite[As(III)]-oxidizing and arsenate[As(V)]-reducing bacterial strain, Pseudomonas sp. HN-2, was isolated from an As-contaminated soil. Phylogenetic analysis based on 16S rRNA gene sequencing indicated that the strain was closely related to Pseudomonas stutzeri. Under aerobic conditions, this strain oxidized 92.0% (61.4μmol/L) of arsenite to arsenate within 3hr of incubation. Reduction of As(V) to As(III) occurred in anoxic conditions. Pseudomonas sp. HN-2 is among the first soil bacteria shown to be capable of both aerobic As(III) oxidation and anoxic As(V) reduction. The strain, as an efficient As(III) oxidizer and As(V) reducer in Pseudomonas, has the potential to impact arsenic mobility in both anoxic and aerobic environments, and has potential application in As remediation processes.

  9. Draft whole-genome sequence of the antibiotic-producing soil isolate Pseudomonas sp. strain 250J.

    PubMed

    Molina-Santiago, Carlos; Udaondo, Zulema; Ramos, Juan-Luis

    2015-04-01

    Bacteria of the genus Pseudomonas are becoming increasing well known for their ability to produce a wide range of antimicrobial compounds. In a large-scale screening for antibiotic producers, we identified a soil isolate that uses 4-hydroxyphenylacetate as the sole carbon source, Pseudomonas sp. strain 250J, which produces cyclic lipodepsipeptides of the xantholysin family during the stationary phase of growth. The closest relatives of this strain are Pseudomonas mosselii, Pseudomonas soli and Pseudomonas entomophila. Sequencing of the 250J genome allowed us to find the genes relevant to antibiotic production, those which allow utilization of 4-hydroxyphenylacetate as a sole carbon source and a set of genes potentially involved in biocontrol.

  10. Pseudomonas extremaustralis sp. nov., a Poly(3-hydroxybutyrate) producer isolated from an antarctic environment.

    PubMed

    López, Nancy I; Pettinari, M Julia; Stackebrandt, Erko; Tribelli, Paula M; Põtter, Markus; Steinbüchel, Alexander; Méndez, Beatriz S

    2009-11-01

    A Gram-negative, mobile, rod-shaped, non-spore-forming bacterium (strain 14-3(T)) was isolated from a temporary pond in Antarctica. On the basis of 16S rRNA gene sequence similarity, strain 14-3(T) was shown to belong to the genus Pseudomonas sensu stricto. Physiological and biochemical tests supported the phylogenetic affiliation. Strain 14-3(T) is closely related to Pseudomonas veronii DSM 11331(T), sharing 99.7% sequence similarity. DNA-DNA hybridization experiments between the two strains showed only moderate reassociation similarity (35.1%). Tests for arginine dihydrolase and nitrate reduction were positive, while those for denitrification, indol production, glucose acidification, urease, ss-galactosidase, esculin, caseine and gelatin hydrolysis were negative. Growth of this bacterium occurred in a range from 4 to 37 degrees C but not at 42 degrees C. It accumulated poly(3-hydroxybutyrate) when grown on sodium octanoate medium. Strain 14-3(T) therefore represents the type strain of a new species, for which the name Pseudomonas extremaustralis sp. nov. is proposed. The type strain 14-3(T) has been deposited as DSM 17835(T) and as CIP 109839(T).

  11. Methylphosphonate Metabolism by Pseudomonas sp. Populations Contributes to the Methane Oversaturation Paradox in an Oxic Freshwater Lake.

    PubMed

    Wang, Qian; Dore, John E; McDermott, Timothy R

    2017-04-03

    The "CH4 oversaturation paradox" has been observed in oxygen-rich marine and lake waters, and viewed to significantly contribute to biosphere cycling of methane, a potent greenhouse gas. Our study focused on the intriguing well-defined pelagic methane enriched zone (PMEZ) in freshwater lakes. Spiking Yellowstone Lake PMEZ samples with (13) C-labeled potential methanogenesis substrates found only (13) C-methylphosphonate (MPn) resulted in (13) CH4 generation. In 16S rRNA gene Illumina libraries, four Pseudomonas sp. operational taxonomic units surprisingly accounted for ∼11% abundance in the PMEZ community. Pseudomonas sp. isolates were also obtained from MPn enrichments with PMEZ water; they were most aggressive in MPn metabolism and their 16S rRNA gene sequences matched 35% of the Illumina PMEZ Pseudomonas reads. Further, two key genes encoding C-P lyase (phnJL, an important enzyme for dealkylation of MPn), were only amplifiable from PMEZ DNA and all PCR generated phnJL clones matched those of the Pseudomonas sp. isolates. Notably, methanogen 16S rRNA signatures were absent in all Illumina libraries and mcrA was not detected via PCR. Collectively, these observations are consistent with the conclusion that MPn metabolism contributes significantly to CH4 oversaturation in Yellowstone Lake and likely other oxic freshwater lake environments, and that Pseudomonas sp. populations are critical participants. This article is protected by copyright. All rights reserved.

  12. Physiological factors affecting carbon tetrachloride dehalogenation by the denitrifying bacterium Pseudomonas sp. strain KC.

    PubMed Central

    Lewis, T A; Crawford, R L

    1993-01-01

    Pseudomonas sp. strain KC was grown on a medium with a low content of transition metals in order to examine the conditions for carbon tetrachloride (CT) transformation. Several carbon sources, including acetate, glucose, glycerol, and glutamate, were able to support CT transformation. The chelators 2,2'-dipyridyl and 1,10-phenanthroline stimulated CT transformation in a rich medium that otherwise did not support this activity. Low (< 10 microM) additions of dissolved iron(II), iron(III), and cobalt(II), as well as an insoluble iron(III) compound, ferric oxyhydroxide, inhibited CT transformation. The addition of 50 microM iron to actively growing cultures resulted in delayed inhibition of CT transformation. CT transformation was seen in aerobic cultures of KC, but with reduced efficiency compared with denitrifying cultures. Inhibition of CT transformation by iron was also seen in aerobically grown cultures. Optimal conditions were used in searching for effective CT transformation activity among denitrifying enrichments grown from samples of aquifer material. No activity comparable to that of Pseudomonas sp. strain KC was found among 16 samples tested. PMID:8517754

  13. Phospholipids and protein adaptation of Pseudomonas sp. to the xenoestrogen tributyltin chloride (TBT).

    PubMed

    Bernat, Przemysław; Siewiera, Paulina; Soboń, Adrian; Długoński, Jerzy

    2014-09-01

    A tributyltin (TBT)-resistant strain of Pseudomonas sp. isolated from an overworked car filter was tested for its adaptation to TBT. The isolate was checked for organotin degradation ability, as well as membrane lipid and cellular protein composition in the presence of TBT. The phospholipid profiles of bacteria, grown with and without increased amounts of TBT, were characterized using liquid chromatography/electrospray ionization/mass spectrometry. The strain reacted to the biocide by changing the composition of its phospholipids. TBT induced a twofold decline in the amounts of many molecular species of phosphatidylglycerol and an increase in the levels of phosphatidic acid (by 58%) and phosphatidylethanolamine (by 70%). An increase in the degree of saturation of phospholipid fatty acids of TBT exposed Pseudomonas sp. was observed. These changes in the phospholipid composition and concentration reflect the mechanisms which support optimal lipid ordering in the presence of toxic xenobiotic. In the presence of TBT the abundances of 16 proteins, including TonB-dependent receptors, porins and peroxidases were modified, which could indicate a contribution of some enzymes to TBT resistance.

  14. Production and optimization of curdlan produced by Pseudomonas sp. QL212.

    PubMed

    Yang, Min; Zhu, Ying; Li, Yumei; Bao, Jie; Fan, Xiangyu; Qu, Yanhong; Wang, Yiwei; Hu, Zhiheng; Li, Qiang

    2016-08-01

    Curdlan is a polysaccharide that consists of β-1,3-linked glucose residues. A polysaccharide-producing bacterium isolated from soil samples was identified as Pseudomonas sp. QL212. The polysaccharide was purified to homogeneity via sequential ethanol precipitation, deproteinization, CM ion-exchange, and gel chromatography sequentially. Analysis of the purified polysaccharide revealed that it consisted of many glucosyl residues, and its molecular weight was only 6.18×10(5)Da. This low molecular weight endowed it with excellent solubility. Infrared and nuclear magnetic resonance spectral analysis confirmed that the polysaccharide was curdlan. Single-factor and Response surface methodology experiments were used to optimize the culture medium and conditions. The optimal culture conditions consisted of seed culture age of 12h, and an incubation temperature of 30°C, with 10% inoculum and a total fluid volume of 75mL in a 250-mL Erlenmeyer flask. The maximum curdlan yield of about 5.92gL(-1) was achieved with an optimal medium consisting of 30.11gL(-1) of sucrose, 5.94gL(-1) of yeast extract, and an initial pH of 8.03. To our best knowledge, this is the highest reported yield of curdlan produced by Pseudomonas sp., and the curdlan production medium components were much simpler than those in previous reports.

  15. Pseudomonas kribbensis sp. nov., isolated from garden soils in Daejeon, Korea.

    PubMed

    Chang, Dong-Ho; Rhee, Moon-Soo; Kim, Ji-Sun; Lee, Yookyung; Park, Mi Young; Kim, Haseong; Lee, Seung-Goo; Kim, Byoung-Chan

    2016-11-01

    Two bacterial strains, 46-1 and 46-2(T), were isolated from garden soil. These strains were observed to be aerobic, Gram-stain negative, rod-shaped, non-spore-forming, motile and catalase and oxidase positive. Phylogenetic analysis based on 16S rRNA gene sequences showed that the two strains shared 100 % sequence similarity with each other and belong to the genus Pseudomonas in the class Gammaproteobacteria. The concatenated 16S rRNA, gyrB, rpoB and rpoD gene sequences further confirmed that the isolates belong to the Pseudomonas koreensis subgroup (SG), with P. koreensis Ps 9-14(T), Pseudomonas moraviensis 1B4(T) and Pseudomonas granadensis F-278,770(T) as their close relatives (>96 % pairwise similarity). DNA-DNA hybridization with the closely related type strain P. koreensis SG revealed a low level of relatedness (<50 %). A cladogram constructed using whole-cell matrix-assisted laser desorption/ionization time-of-flight (WC-MALDI-TOF) MS analysis showed the isolates formed a completely separate monophyletic group. The isolates were negative for utilization of glycogen, D-psicose, α-keto butyric acid, α-keto valeric acid, succinamic acid and D, L-α-glycerol phosphate. In contrast, all these reactions were positive in P. koreensis JCM 14769(T) and P. moraviensis DSM 16007(T). The fatty acid C17:0 cyclo was detected as one of the major cellular fatty acids (>15 %) in the isolates but it was a minor component (<4 %) in both reference type strains. In contrast, the fatty acid, C12:0 was not observed in the isolates but was present in both reference strains. Based on differences such as phylogenetic position, low-level DNA-DNA hybridization, WC-MALDI-TOF MS analysis, fluorescence pigmentation, fatty acid profiles, and substrate utilization, we propose that the isolates 46-1 and 46-2(T) represent a novel species of the genus Pseudomonas, for which the name Pseudomonas kribbensis sp. nov. is proposed; the type strain is 46-2(T) (=KCTC 32541(T) = DSM 100278(T)).

  16. Pseudomonas coleopterorum sp. nov., a cellulase-producing bacterium isolated from the bark beetle Hylesinus fraxini.

    PubMed

    Menéndez, Esther; Ramírez-Bahena, Martha H; Fabryová, Anna; Igual, José M; Benada, Oldrich; Mateos, Pedro F; Peix, Alvaro; Kolařík, Miroslav; García-Fraile, Paula

    2015-09-01

    We isolated a strain coded Esc2Am(T) during a study focused on the microbial diversity of adult specimens of the bark beetle Hylesinus fraxini. Its 16S rRNA gene sequence had 99.4% similarity with respect to its closest relative, Pseudomonas rhizosphaerae IH5(T). The analysis of partial sequences of the housekeeping genes rpoB, rpoD and gyrB confirmed that strain Esc2Am(T) formed a cluster with P. rhizosphaerae IH5(T) clearly separated from the remaining species of the genus Pseudomonas. Strain Esc2Am(T) had polar flagella and could grow at temperatures from 4 °C to 30 °C. The respiratory quinone was Q9 and the main fatty acids were C16 : 0, C18 : 1ω7c and/or C18 : 1ω6c in summed feature 8 and C16 : 1ω7c and/or C16 : 1ω6c in summed feature 3. DNA-DNA hybridization results showed 51% relatedness with respect to P. rhizosphaerae IH5(T). Oxidase, catalase and urease-positive, the arginine dihydrolase system was present but nitrate reduction and β-galactosidase production were negative. Aesculin hydrolysis was positive. Based on the results from the genotypic, phenotypic and chemotaxonomic analyses, we propose the classification of strain Esc2Am(T) as representing a novel species of the genus Pseudomonas, for which we propose the name Pseudomonas coleopterorum sp. nov. The type strain is Esc2Am(T) ( = LMG 28558(T)= CECT 8695(T)).

  17. Metabolism of 2-, 3- and 4-hydroxybenzoates by soil isolates Alcaligenes sp. strain PPH and Pseudomonas sp. strain PPD.

    PubMed

    Deveryshetty, Jaigeeth; Suvekbala, V; Varadamshetty, Gautham; Phale, Prashant S

    2007-03-01

    Pseudomonas sp. strain PPD and Alcaligenes sp. strain PPH isolated from soil by enrichment culture technique utilize 2-, 3- and 4-hydroxybenzoates as the sole source of carbon and energy. The degradation pathways were elucidated by performing whole-cell O(2) uptake, enzyme activity and induction studies. Depending on the mixture of carbon source and the preculture condition, strain PPH was found to degrade 2-hydroxybenzoate either via the catechol or gentisate route and has both salicylate 1-hydroxylase and salicylate 5-hydroxylase. Strain PPD utilizes 2-hydroxybenzoate via gentisate. Both strains degrade 3- and 4-hydroxybenzoate via gentisate and protocatechuate, respectively. Enzymes were induced by respective hydroxybenzoate. Growth pattern, O(2) uptake and enzyme activity profiles on the mixture of three hydroxybenzoates as a carbon source suggest coutilization by both strains. When 3- or 4-hydroxybenzoate grown culture was used as an inoculum, strain PPH failed to utilize 2-hydroxybenzoate via catechol, indicating the modulation of the metabolic pathways, thus generating metabolic diversity.

  18. The nitrogen-fixation island insertion site is conserved in diazotrophic Pseudomonas stutzeri and Pseudomonas sp. isolated from distal and close geographical regions.

    PubMed

    Venieraki, Anastasia; Dimou, Maria; Vezyri, Eleni; Vamvakas, Alexandros; Katinaki, Pagona-Artemis; Chatzipavlidis, Iordanis; Tampakaki, Anastasia; Katinakis, Panagiotis

    2014-01-01

    The presence of nitrogen fixers within the genus Pseudomonas has been established and so far most isolated strains are phylogenetically affiliated to Pseudomonas stutzeri. A gene ortholog neighborhood analysis of the nitrogen fixation island (NFI) in four diazotrophic P. stutzeri strains and Pseudomonas azotifigens revealed that all are flanked by genes coding for cobalamin synthase (cobS) and glutathione peroxidise (gshP). The putative NFIs lack all the features characterizing a mobilizable genomic island. Nevertheless, bioinformatic analysis P. stutzeri DSM 4166 NFI demonstrated the presence of short inverted and/or direct repeats within both flanking regions. The other P. stutzeri strains carry only one set of repeats. The genetic diversity of eleven diazotrophic Pseudomonas isolates was also investigated. Multilocus sequence typing grouped nine isolates along with P. stutzeri and two isolates are grouped in a separate clade. A Rep-PCR fingerprinting analysis grouped the eleven isolates into four distinct genotypes. We also provided evidence that the putative NFI in our diazotrophic Pseudomonas isolates is flanked by cobS and gshP genes. Furthermore, we demonstrated that the putative NFI of Pseudomonas sp. Gr65 is flanked by inverted repeats identical to those found in P. stutzeri DSM 4166 and while the other P. stutzeri isolates harbor the repeats located in the intergenic region between cobS and glutaredoxin genes as in the case of P. stutzeri A1501. Taken together these data suggest that all putative NFIs of diazotrophic Pseudomonas isolates are anchored in an intergenic region between cobS and gshP genes and their flanking regions are designated by distinct repeats patterns. Moreover, the presence of almost identical NFIs in diazotrophic Pseudomonas strains isolated from distal geographical locations around the world suggested that this horizontal gene transfer event may have taken place early in the evolution.

  19. Pseudomonas guguanensis sp. nov., a gammaproteobacterium isolated from a hot spring.

    PubMed

    Liu, You-Cheng; Young, Li-Sen; Lin, Shih-Yao; Hameed, Asif; Hsu, Yi-Han; Lai, Wei-An; Shen, Fo-Ting; Young, Chiu-Chung

    2013-12-01

    An aerobic, Gram-stain-negative, rod-shaped bacterium (designated strain CC-G9A(T)), motile by a polar-flagellum, was isolated from a hot spring water sample in Taiwan. Strain CC-G9A(T) could grow at 20-42 °C, pH 6.0-10.0 and tolerate up to 7% (w/v) NaCl. The 16S rRNA gene sequence analysis of strain CC-G9A(T) showed pairwise sequence similarity to Pseudomonas mendocina LMG 1223(T) (97.7%), Pseudomonas alcaligenes ATCC 14909(T) (97.8 %), Pseudomonas alcaliphila DSM 17744(T) (97.8 %), Pseudomonas toyotomiensis JCM 15604(T) (97.6 %), Pseudomonas oleovorans subsp. lubricantis DSM 21016(T) (97.6 %) and Pseudomonas argentinensis BCRC 17807(T) (97.5 %), and lower sequence similarity to other species of the genus Pseudomonas. According to DNA-DNA association analysis, the relatedness of strain CC-G9A(T) to P. mendocina BCRC 10458(T), P. alcaliphila DSM 17744(T), P. alcaligenes BCRC 11893(T), P. oleovorans subsp. lubricantis DSM 21016(T), P. argentinensis BCRC 17807(T) and P. oleovorans subsp. oleovorans BCRC 11902 was 55.1±3.1, 13.7±1.5, 14.1±1.8, 58.5±1.1, 28.9±2.0 and 28.6±1.8 %, respectively. The evolutionary trees reconstructed based on 16S rRNA, gyrB and rpoB gene sequences revealed varying phylogenetic neighbourhoods of strain CC-G9A(T) with regard to the most closely related type strains. The predominant quinone system was ubiquinone (Q-9) and the DNA G+C content was 64.3±1.3 mol%. The major fatty acids were C10 : 0 3-OH, C12 : 0, C12 : 0 3-OH, C16 : 0 and summed features 3 and 8 consisting of C16 : 1ω7c/C16 : 1ω6c and C18 : 1ω7c/C18 : 1ω6c, respectively. The major polar lipids were diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine and phosphatidylglycerol. According to distinct phylogenetic, phenotypic and chemotaxonomic features, strain CC-G9A(T) is proposed to represent a novel species within the genus Pseudomonas for which the name Pseudomonas guguanensis sp. nov. is proposed. The type

  20. Pseudomonas yamanorum sp. nov., a psychrotolerant bacterium isolated from a subantarctic environment.

    PubMed

    Arnau, Víctor Gonzalo; Sánchez, Leandro Arturo; Delgado, Osvaldo Daniel

    2015-02-01

    A psychrotolerant strain, 8H1(T), was isolated from soil samples collected in Isla de los Estados, Ushuaia, Argentina. Cells were Gram-negative, aerobic, straight rods, occurring singly or in pairs, non-spore-forming and motile by means of two polar flagella. The isolate was able to grow in the range 4-35 °C, with optimum growth at 28 °C. The predominant cellular fatty acids were summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c), C16 : 0 and summed feature 8 (C18 : 1ω6c and/or C18 : 1ω7c). The polar lipid pattern of strain 8H1(T) comprised phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine and an unknown phospholipid. Ubiquinone 9 (Q-9) was the predominant lipoquinone. The DNA G+C content was 59.8 mol%. 16S rRNA gene sequence-based phylogeny suggested the affiliation of strain 8H1(T) to the 'Pseudomonas fluorescens group', displaying ≥98.5 % sequence similarity to 29 type strains. A multilocus sequence analysis (MLSA) study performed by concatenating 16S rRNA, gyrB, rpoD and rpoB gene sequences showed that isolate 8H1(T) could be discriminated from closely related species of the genus Pseudomonas and placed in the 'Pseudomonas gessardii subgroup', including the species with the highest MLSA sequence similarities: Pseudomonas brenneri (96.2 %), P. gessardii (96.1 %), P. proteolytica (96.0 %), P. meridiana (96.0 %) and P. mucidolens (95.4 %). DNA-DNA hybridization analysis between 8H1(T) and the type strains of these closely related species revealed relatedness values of 27.0, 8.8, 41.2, 39.7 and 46.1 %, respectively. These results, together with differences in several phenotypic features, support the classification of a novel species, for which the name Pseudomonas yamanorum sp. nov. is proposed. The type strain is 8H1(T) ( = DSM 26522(T) = CCUG 63249(T) = LMG 27247(T)).

  1. Pseudomonas songnenensis sp. nov., isolated from saline and alkaline soils in Songnen Plain, China.

    PubMed

    Zhang, Lei; Pan, Yuanyuan; Wang, Kaibiao; Zhang, Xiaoxia; Zhang, Shuang; Fu, Xiaowei; Zhang, Cheng; Jiang, Juquan

    2015-03-01

    The strain NEAU-ST5-5(T) was isolated from the saline and alkaline soil in Songnen Plain, North East of China. The bacterium was found to be aerobic, Gram-stain negative, rod-shaped and motile by means of several polar flagella. It forms yellow-orange colonies with a radial wrinkled surface. Phylogenetic analyses based on the separate 16S rRNA gene sequences and concatenated 16S rRNA, gyrB and rpoD gene sequences indicated that it belongs to the genus Pseudomonas in the class Gammaproteobacteria. Strain NEAU-ST5-5(T) shows gene sequence similarities of 98.8-97.1 % for 16S rRNA, 90.5-78.4 % for gyrB and 90.4-71.1 % for rpoD with type strains of the closely related species of the genus Pseudomonas, respectively. DNA-DNA hybridization relatedness between strain NEAU-ST5-5(T) and type strains of the most closely related species, Pseudomonas stutzeri DSM 5190(T), P. xanthomarina DSM 18231(T), P. kunmingensis CGMCC 1.12273(T), P. alcaliphila DSM 17744(T) and P. oleovorans subsp. lubricantis DSM 21016(T) were 43 ± 1 to 25 ± 2 %. The major fatty acids (>10 %) were determined to be C18:1 ω7c/C18:1 ω6c, C16:1 ω7c/C16:1 ω6c and C16:0, the predominant respiratory quinone was identified as ubiquinone 9 and polar lipids were found to consist of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, one unknown phospholipid, one unidentified aminophospholipid and one unknown lipid. The genotypic, chemotaxonomic and phenotypic analysis indicated that strain NEAU-ST5-5(T) represents a novel species of the genus Pseudomonas, for which the name Pseudomonas songnenensis sp. nov. is proposed. The type strain is NEAU-ST5-5(T) (=ACCC 06361(T) = DSM 27560(T)).

  2. Genome Sequence of the Deep-Sea Denitrifier Pseudomonas sp. Strain MT-1, Isolated from the Mariana Trench.

    PubMed

    Fujinami, Shun; Oikawa, Yuji; Araki, Takuma; Shinmura, Yui; Midorikawa, Ryota; Ishizaka, Hikari; Kato, Chiaki; Horikoshi, Koki; Ito, Masahiro; Tamegai, Hideyuki

    2014-12-18

    Pseudomonas sp. strain MT-1 was the first deep-sea denitrifier isolated and characterized from mud recovered from a depth of 11,000 m in the Mariana Trench. We report here the genome sequence of this bacterium, which contributes to our understanding of denitrification and bioenergetics in the deep sea.

  3. Involvement of phenazines and biosurfactants in biocontrol of Pythium myriotylum root rot on cocoyam by Pseudomonas sp. CMR12A

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pseudomonas sp. CMR12a was isolated from the rhizosphere of the tropical tuber crop cocoyam and produces both phenazines and cyclic lipopeptide (CLP) biosurfactants. CMR12a was shown to be an efficient biocontrol agent of P. myriotylum on cocoyam. To assess the importance of phenazine and biosurfact...

  4. Pseudomonas sp. xylanase for clarification of Mausambi and Orange fruit juice

    NASA Astrophysics Data System (ADS)

    Sharma, Pawan Kumar; Chand, Duni

    2012-07-01

    Xylanase can be usd for many Industrial applications and juice clarification is one of them. Pseudomonas sp. xylanase was used for fruit juice clarification in free State. Maximum amount of juice clarification was in case of Mausambi juice was observed at 40 C∞ and 52 hours, in case of free enzyme treated juice there is 46.9% increase in clarity and 1.7 fold increase in reducing sugars of the juice and enzyme dose was optimized as 8U with maximum flow rate of 6 ml/min at this dose. In case of orange juice in free enzyme treated juice maximum clarity was observed at 40 C∞ and 52 hours, juice was found to be 42.14 % clear with increase of 1.9 fold of reducing sugars, enzyme dose optimized was 8.06U with maximum flow rate of 0.86 ml/min.

  5. Indigo production by Pseudomonas sp. J26, a marine naphthalene-degrading strain.

    PubMed

    Mercadal, Juan Pablo Riva; Isaac, Paula; Siñeriz, Faustino; Ferrero, Marcela Alejandra

    2010-06-01

    A technique developed to determine naphthalene dioxygenase (NDO) activity was optimized and used to study the biotransformation of indole to indigo by Pseudomonas sp. J26 whole cells. The maximum production of indigo was achieved at 25 degrees C using 2.5 mM indole when J26 was grown in the complex medium JPP, while indole concentrations higher than 4 mM proved toxic for cells. The maximum rate of indigo production was 0.56 nmol min(-1) mg dry biomass(-1), obtaining 75.5 microM of indigo after 8 h of incubation, while a maximal concentration (138.1 microM) of indigo was obtained after 20 h.

  6. Oxidation of biphenyl by a multicomponent enzyme system from Pseudomonas sp. strain LB400.

    PubMed Central

    Haddock, J D; Nadim, L M; Gibson, D T

    1993-01-01

    Pseudomonas sp. strain LB400 grows on biphenyl as the sole carbon and energy source. This organism also cooxidizes several chlorinated biphenyl congeners. Biphenyl dioxygenase activity in cell extract required addition of NAD(P)H as an electron donor for the conversion of biphenyl to cis-2,3-dihydroxy-2,3-dihydrobiphenyl. Incorporation of both atoms of molecular oxygen into the substrate was shown with 18O2. The nonlinear relationship between enzyme activity and protein concentration suggested that the enzyme is composed of multiple protein components. Ion-exchange chromatography of the cell extract gave three protein fractions that were required together to restore enzymatic activity. Similarities with other multicomponent aromatic hydrocarbon dioxygenases indicated that biphenyl dioxygenase may consist of a flavoprotein and iron-sulfur proteins that constitute a short electron transport chain involved in catalyzing the incorporation of both atoms of molecular oxygen into the aromatic ring. Images PMID:8419290

  7. Physical comparison of parathion hydrolase plasmids from Pseudomonas diminuta and Flavobacterium sp.

    PubMed

    Mulbry, W W; Kearney, P C; Nelson, J O; Karns, J S

    1987-09-01

    Restriction maps of two plasmids encoding parathion hydrolase have been determined. pPDL2 is a 39-kb plasmid harbored by Flavobacterium sp. (ATCC 27551), while pCMS1 is a 70-kb plasmid found in Pseudomonas diminuta (strain MG). Both plasmids previously have been shown to share homologous parathion hydrolase genes (termed opd for organophosphate degradation) as judged by DNA-DNA hybridization and restriction mapping. In the present study, we conducted DNA hybridization experiments using each of nine PstI restriction fragments from pCMS1 as probes against Flavobacterium plasmid DNA. The opd genes of both plasmids are located within a highly conserved region of approximately 5.1 kb. This region of homology extends approximately 2.6 kb upstream and 1.7 kb downstream from the opd genes. No homology between the two plasmids is evident outside of this region.

  8. Effect of shutdown on styrene removal in a biofilter inoculated with Pseudomonas sp. SR-5.

    PubMed

    Jang, Jong Hee; Hirai, Mitsuyo; Shoda, Makoto

    2006-02-28

    Styrene gas removal was carried out in a biofilter inoculated with a styrene-degrading Pseudomonas sp. SR-5 using a mixed packing material of peat and ceramic under the non-sterile condition. More than 86% removal efficiency was obtained at styrene load of 5-93 g m(-3) h(-1) for 62 days operation period and 78% carbon of removed styrene was converted to CO2. Thereafter, three kinds of styrene shutdown experiments were conducted: (i) air and mineral medium were supplied for 4 days, (ii) complete shutdown, namely no styrene, air and moisture supply was conducted for 3 days, and (iii) only air was supplied for 11 days. When styrene gas was re-supplied after (i) and (iii) shutdown experiments, styrene removal efficiency rapidly recovered, but after (ii) shutdown, recovery of styrene removal was significantly delayed. Supply of air during shutdown period was found to be enough to resume microbial activity to degrade styrene.

  9. Natural Electrotransformation of Lightning-Competent Pseudomonas sp. Strain N3 in Artificial Soil Microcosms

    PubMed Central

    Cérémonie, Hélène; Buret, François; Simonet, Pascal; Vogel, Timothy M.

    2006-01-01

    The lightning-competent Pseudomonas sp. strain N3, recently isolated from soil, has been used to study the extent of natural electrotransformation (NET) or lightning transformation as a horizontal gene transfer mechanism in soil. The variation of electrical fields applied to the soil with a laboratory-scale lightning system provides an estimate of the volume of soil affected by NET. Based on the range of the electric field that induces NET of Pseudomonas strain N3, the volume of soil, where NET could occur, ranges from 2 to 950 m3 per lightning strike. The influence of DNA parameters (amount, size, and purity) and DNA soil residence time were also investigated. NET frequencies (electrotransformants/recipient cells) ranged from 10−8 for cell lysate after 1 day of residence in soil to 4 × 10−7 with a purified plasmid added immediately before the lightning. The electrical field gradient (in kilovolts per cm) also played a role as NET frequencies ranging from 1 × 10−5 at 2.3 kV/cm to 1.7 × 10−4 at 6.5 kV/cm. PMID:16597934

  10. Degradation characteristics of methyl ethyl ketone by Pseudomonas sp. KT-3 in liquid culture and biofilter.

    PubMed

    Lee, Tae Ho; Kim, Jaisoo; Kim, Min-Joo; Ryu, Hee Wook; Cho, Kyung-Suk

    2006-04-01

    With ketone pollution forming an ever-growing problem, it is important to identify a ketone-degrading microorganism and establish its effect. Here, a methyl ethyl ketone (MEK)-degrading bacterium, Pseudomonas sp. KT-3, was isolated and its MEK degradation characteristics were examined in liquid cultures and a polyurethane-packed biofilter. In liquid cultures, strain KT-3 could degrade other ketone solvents, including diethyl ketone (DK), methyl propyl ketone (MPK), methyl isopropyl ketone (MIPK), methyl isobutyl ketone (MIBK), methyl butyl ketone (MBK) and methyl isoamyl ketone (MIAK). The maximum specific growth rate (mumax) of the isolate was 0.136 h(-1) in MEK medium supplemented with MEK as a sole carbon source, and kinetically, the maximum removal rate (Vm) and saturation constant (Km) for MEK were 12.28 mM g(-1)DCW h(-1) (DCW: dry cell weight) and 1.64 mM, respectively. MEK biodegradation by KT-3 was suppressed by the addition of MIBK or acetone, but not by toluene. In the tested biofilter, KT-3 exhibited a>90% removal efficiency for MEK inlet concentrations of around 500 ppmv at a space velocity (SV) of 150 h(-1). The elimination capacity of MEK was more influenced by SV than by the inlet concentration. Kinetic analysis showed that the maximum MEK removal rate (Vm) was 690 g m(-3) h(-1) and the saturation constant (Km) was 490 ppmv. Collectively, these results indicate the polyurethane sequencing batch biofilter with Pseudomonas sp. KT-3 will provide an excellent performance in the removal of gaseous MEK.

  11. Deciphering a survival strategy during the interspecific competition between Bacillus cereus MSM-S1 and Pseudomonas sp. MSM-M1

    PubMed Central

    Annagiri, Sumana

    2016-01-01

    Interspecific competition in bacteria governs colony growth dynamics and pattern formation. Here, we demonstrate an interesting phenomenon of interspecific competition between Bacillus cereus MSM-S1 and Pseudomonas sp. MSM-M1, where secretion of an inhibitor by Pseudomonas sp. is used as a strategy for survival. Although B. cereus grows faster than Pseudomonas sp., in the presence of Pseudomonas sp. the population of B. cereus reduces significantly, whereas Pseudomonas sp. do not show any marked alteration in their population growth. Appearance of a zone of inhibition between growing colonies of two species on nutrient agar prevents the expanding front of the MSM-S1 colony from accessing and depleting nutrients in the region occupied by MSM-M1, thereby aiding the survival of the slower growing MSM-M1 colonies. To support our experimental results, we present simulations, based on a chemotactic model of colony growth dynamics. We demonstrate that the chemical(s) secreted by Pseudomonas sp. is responsible for the observed inhibition of growth and spatial pattern of the B. cereus MSM-S1 colony. Our experimental results are in excellent agreement with the numerical results and confirm that secreted inhibitors enable Pseudomonas sp. to survive and coexist in the presence of faster growing B. cereus, in a common niche. PMID:28018625

  12. Biodegradation of the organophosphorus insecticide diazinon by Serratia sp. and Pseudomonas sp. and their use in bioremediation of contaminated soil.

    PubMed

    Cycoń, Mariusz; Wójcik, Marcin; Piotrowska-Seget, Zofia

    2009-07-01

    An enrichment culture technique was used for the isolation of bacteria responsible for biodegradation of diazinon in soil. Three bacterial strains were screened and identified by MIDI-FAME profiling as Serratia liquefaciens, Serratia marcescens and Pseudomonas sp. All isolates were able to grow in mineral salt medium (MSM) supplemented with diazinon (50 mgL(-1)) as a sole carbon source, and within 14d 80-92% of the initial dose of insecticide was degraded by the isolates and their consortium. Degradation of diazinon was accelerated when MSM was supplemented with glucose. However, this process was linked with the decrease of pH values, after glucose utilization. Studies on biodegradation in sterilized soil showed that isolates and their consortium exhibited efficient degradation of insecticide (100mg kg(-1) soil) with a rate constant of 0.032-0.085d(-1), and DT(50) for diazinon was ranged from 11.5d to 24.5d. In contrast, degradation of insecticide in non-sterilized soil, non-supplemented earlier with diazinon, was characterized by a rate constant of 0.014d(-1) and the 7-d lag phase, during which only 2% of applied dose was degraded. The results suggested a strong correlation between microbial activity and chemical processes during diazinon degradation. Moreover, isolated bacterial strains may have potential for use in bioremediation of diazinon-contaminated soils.

  13. Nitrate removal efficiency of bacterial consortium (Pseudomonas sp. KW1 and Bacillus sp. YW4) in synthetic nitrate-rich water.

    PubMed

    Rajakumar, Sundaram; Ayyasamy, Pudukadu Munusamy; Shanthi, Kuppusamy; Thavamani, Palanisami; Velmurugan, Palanivel; Song, Young Chae; Lakshmanaperumalsamy, Perumalsamy

    2008-09-15

    The efficiency of bacterial isolates to reduce nitrate from synthetic nitrate-rich water was tested using a batch scale process. Two efficient nitrate reducing bacterial species were isolated from water samples collected from Kodaikanal and Yercaud lakes. Bacterial analysis of the samples revealed the presence of nitrate reducing bacteria belonging to the genera Pseudomonas, Bacillus, Micrococcus and Alcaligenes. Among the isolates, the consortium of Pseudomonas sp. KW1 and Bacillus sp. YW4 was found to be efficient in nitrate reduction. Influences of various carbon sources, incubation temperature and pH on nitrate reduction from synthetic wastewater were also studied. The results showed a rapid and efficient process of nitrate removal (99.4%) from synthetic wastewater supplemented with starch (1%), inoculated by bacterial consortium (Pseudomonas sp. KW1 and Bacillus sp. YW4) at incubation temperature of 30 degrees C at pH 7. This observation has led to the conclusion that the bacterial consortium was responsible for nitrate removal from synthetic nitrate-rich wastewater.

  14. Description of Pseudomonas asuensis sp. nov. from biological soil crusts in the Colorado plateau, United States of America.

    PubMed

    Reddy, Gundlapally Sathyanarayana; Garcia-Pichel, Ferran

    2015-01-01

    A Gram-negative, aerobic, non spore-forming, non-motile, rod-shaped, yellow pigmented bacterium CP155-2(T) was isolated from a biological soil crusts sample collected in the Colorado plateau, USA and subjected to polyphasic taxonomic characterization. Strain CP155-2(T) contained summed feature 3 (C(16:1)ω5c/C(16:1)ω7c) and C(18:1)ω7c as major fatty acids and diphosphatidylglycerol (DPG) along with phosphatidylethanolamine (PE) and phosphatidylglycerol (PG) as major polar lipids. Based on these characteristics CP155-2(T) was assigned to the genus Pseudomonas. Phylogenetic analysis based on 16S rRNA gene sequence further confirmed the affiliation of CP155-2(T) to the genus Pseudomonas and showed a 16S rRNA gene sequence similarity of less than 98.7% with already described species of the genus. Pseudomonas luteola, Pseudomonas zeshuii, and Pseudomonas duriflava were identified as the closest species of the genus Pseudomonas with 16S rRNA gene sequence similarities of 98.7%, 98.6%, and 96.9%, respectively. The values for DNA¨CDNA relatedness between CP155-2(T) and Pseudomonas luteola and Pseudomonas zeshuii were 23% and 14% respectively a value below the 70% threshold value, indicating that strain CP155-2(T) belongs to a novel taxon of the genus Pseudomonas lineage. The novel taxon status was strengthened by a number of phenotypic differences wherein CP155-2(T) was positive for oxidase, negative for gelatin hydrolysis, could utilize D-cellobiose, D-raffinose, L-rhamnose, D-sorbitol but not L-aspartic acid and L-glutamic acid. Based on the collective differences strain CP155-2(T) exhibited, it was identified as a novel species and the name Pseudomonas asuensis sp. nov. was proposed. The type strain of Pseudomonas asuensis sp. nov. is CP155-2(T) (DSM 17866(T) =ATCC BAA-1264(T) =JCM13501(T) =KCTC 32484(T)).

  15. Molecular characterization of a novel family-46 chitosanase from Pseudomonas sp. A-01.

    PubMed

    Ando, Akikazu; Saito, Akihiro; Arai, Sayaka; Usuda, Sakiko; Furuno, Maiko; Kaneko, Naomi; Shida, Osamu; Nagata, Yoshiho

    2008-08-01

    Pseudomonas sp. A-01, isolated as a strain with chitosan-degrading activity, produced a 28 kDa chitosanase. Following purification of the chitosanase (Cto1) and determination of its N-terminal amino acid sequence, the corresponding gene (cto1) was cloned by a reverse-genetic technique. The gene encoded a protein, composed of 266 amino acids, including a putative signal sequence (1-28), that showed an amino acid sequence similar to known family-46 chitosanases. Cto1 was successfully overproduced and was secreted by a Brevibacillus choshinensis transformant carrying the cto1 gene on expression plasmid vector pNCMO2. The purified recombinant Cto1 protein was stable at pH 5-8 and showed the best chitosan-hydrolyzing activity at pH 5. Replacement of two acidic amino acid residues, Glu23 and Asp41, which correspond to previously identified active centers in Streptomyces sp. N174 chitosanase, with Gln and Asn respectively caused a defect in the hydrolyzing activity of the enzyme.

  16. Pseudomonas cuatrocienegasensis sp. nov., isolated from an evaporating lagoon in the Cuatro Cienegas valley in Coahuila, Mexico.

    PubMed

    Escalante, Ana E; Caballero-Mellado, Jesús; Martínez-Aguilar, Lourdes; Rodríguez-Verdugo, Alejandra; González-González, Andrea; Toribio-Jiménez, Jeiry; Souza, Valeria

    2009-06-01

    Nine Gram-negative, rod-shaped, non-spore-forming isolates with identical or very similar repetitive-sequence-based PCR profiles were recovered from an evaporative lagoon in Mexico. Two strains, designated 1N(T) and 3N, had virtually identical 16S rRNA gene sequences and, on the basis of these sequences, were identified as members of the genus Pseudomonas, with Pseudomonas peli R-20805(T) as the closest relative. All nine isolates had practically identical whole-cell protein profiles. The major fatty acids [C(16 : 0,) C(18 : 1)omega7c and summed feature a (C(16 : 1)omega7 and/or C(16 : 1)omega6c)] of strains 1N(T) and 3N supported their affiliation with the genus Pseudomonas. The DNA-DNA reassociation values with respect to P. peli LMG 23201(T) and other closely related Pseudomonas species were <15 %. Physiological and biochemical tests allowed phenotypic differentiation of the strains analysed, including strain 1N(T), from the five phylogenetically closest Pseudomonas species. On the basis of the data obtained by using this polyphasic taxonomic approach, the nine strains represent a novel species, for which the name Pseudomonas cuatrocienegasensis sp. nov. is proposed. The type strain is 1N(T) (=LMG 24676(T)=CIP 109853(T)).

  17. Pseudomonas granadensis sp. nov., a new bacterial species isolated from the Tejeda, Almijara and Alhama Natural Park, Granada, Spain.

    PubMed

    Pascual, Javier; García-López, Marina; Bills, Gerald F; Genilloud, Olga

    2015-02-01

    During the course of screening bacterial isolates as sources of as-yet unknown bioactive compounds with pharmaceutical applications, a chemo-organotrophic, Gram-negative bacterium was isolated from a soil sample taken from the Tejeda, Almijara and Alhama Natural Park, Granada, Spain. Strain F-278,770(T) was oxidase- and catalase-positive, aerobic, with a respiratory type of metabolism with oxygen as the terminal electron acceptor, non-spore-forming and motile by one polar flagellum, although some cells had two polar flagella. Phylogenetic analysis of the 16S rRNA, gyrB, rpoB and rpoD genes revealed that strain F-278,770(T) belongs to the Pseudomonas koreensis subgroup (Pseudomonas fluorescens lineage), with Pseudomonas moraviensis, P. koreensis, P. baetica and P. helmanticensis as its closest relatives. Chemotaxonomic traits such as polar lipid and fatty acid compositions and G+C content of genomic DNA corroborated the placement of strain F-278,770(T) in the genus Pseudomonas. DNA-DNA hybridization assays and phenotypic traits confirmed that this strain represents a novel species of the genus Pseudomonas, for which the name Pseudomonas granadensis sp. nov. is proposed. The type strain is F-278,770(T) ( = DSM 28040(T) = LMG 27940(T)).

  18. Pseudomonas kuykendallii sp. nov.: a novel γ-proteobacteria isolated from a hexazinone degrading bioreactor.

    PubMed

    Hunter, William J; Manter, Daniel K

    2012-08-01

    Three strains of Gram-negative bacteria designated strains H2(T), H6, and H7 were isolated from bioreactors that degraded the herbicide hexazinone. Similar morphological characteristics, cellular fatty acid profiles, and 16S rRNA gene sequences show that the isolates are members of the same species. These characteristics also show that the isolates belong to the genus Pseudomonas with P. graminis, P. putida, and P. stutzeri as close relatives. The 16S rRNA gene of the H2(T) strain differed from that of type strains for P. graminis, P. putida, and P. stutzeri by 1.9, 2.5, and 2.7 %, respectively, indicating that the H2(T), H6, and H7 strains are related to P. graminis, P. putida, and P. stutzeri but are different enough to represent a novel species. The G+C content of the three strains averaged 61.2 ± 0.8 mol% which is similar to the values reported for P. graminis (61), P. putida (61.6), and P. stutzeri (62.2-65.5). The major cellular fatty acids present in the H2(T) strain were C(18:1) ω7c/C (18:1) ω6c (34.3 %), C(16:1) ω6c/C(16:1) ω7c (27.4 %), C(16:0) (20.6 %), C(12:0) (7.9 %), C(12:0) 3-OH (4.5 %), and C(10:0) 3-OH (3.1 %). The name Pseudomonas kuykendallii sp. nov. is proposed for these bacteria.

  19. Evidence for a novel pathway in the degradation of fluorene by Pseudomonas sp. strain F274.

    PubMed Central

    Grifoll, M; Selifonov, S A; Chapman, P J

    1994-01-01

    A fluorene-utilizing microorganism, identified as a species of Pseudomonas, was isolated from soil severely contaminated from creosote use and was shown to accumulate six major metabolites from fluorene in washed-cell incubations. Five of these products were identified as 9-fluorenol, 9-fluorenone, (+)-1,1a-dihydroxy-1-hydro-9-fluorenone, 8-hydroxy-3,4-benzocoumarin, and phthalic acid. This last compound was also identified in growing cultures supported by fluorene. Fluorene assimilation into cell biomass was estimated to be approximately 50%. The structures of accumulated products indicate that a previously undescribed pathway of fluorene catabolism is employed by Pseudomonas sp. strain F274. This pathway involves oxygenation of fluorene at C-9 to give 9-fluorenol, which is then dehydrogenated to the corresponding ketone, 9-fluorenone. Dioxygenase attack on 9-fluorenone adjacent to the carbonyl group gives an angular diol, 1,1a-dihydroxy-1-hydro-9-fluorenone. Identification of 8-hydroxy-3,4-benzocoumarin and phthalic acid suggests that the five-membered ring of the angular diol is opened first and that the resulting 2'-carboxy derivative of 2,3-dihydroxy-biphenyl is catabolized by reactions analogous to those of biphenyl degradation, leading to the formation of phthalic acid. Cell extracts of fluorene-grown cells possessed high levels of an enzyme characteristic of phthalate catabolism, 4,5-dihydroxyphthalate decarboxylase, together with protocatechuate 4,5-dioxygenase. On the basis of these findings, a pathway of fluorene degradation is proposed to account for its conversion to intermediary metabolites. A range of compounds with structures similar to that of fluorene was acted on by fluorene-grown cells to give products consistent with the initial reactions proposed. PMID:8074523

  20. Cloning and sequencing of beta-1,4-endoglucanase gene (celA) from Pseudomonas sp. YD-15.

    PubMed

    Her, S; Lee, H S; Choi, S J; Choi, S W; Choi, H J; Yoon, S S; Oh, D H

    1999-12-01

    A beta-1,4-endoglucanase gene (celA) from Pseudomonas sp. YD-15 was cloned in Escherichia coli DH5 alpha and its nucleotide sequence determined. The open reading frame of celA was 1830 base pairs and the enzyme was composed of 609 amino acids with a molecular weight of 63,617 Da. The deduced amino acid sequence and putative active site of CelA had high amino acid homology with family E cellulases. By dot blot analysis, the induction of celA according to carbon sources was determined. The transcripts hybridizing to the internal fragment of celA were detected in total RNA isolated from Pseudomonas sp. YD-15 cells grown on avicel and glycerol, but not from cells grown on glucose and cellobiose.

  1. Biosurfactant produced by novel Pseudomonas sp. WJ6 with biodegradation of n-alkanes and polycyclic aromatic hydrocarbons.

    PubMed

    Xia, Wenjie; Du, Zhifeng; Cui, Qingfeng; Dong, Hao; Wang, Fuyi; He, Panqing; Tang, YongChun

    2014-07-15

    Alkanes and polycyclic aromatic hydrocarbons (PAHs) have threatened the environment due to toxicity and poor bioavailability. Interest in degradation of these hazardous materials by biosurfactant-producing bacteria has been steadily increasing in recent years. In this work, a novel biosurfactant-producing Pseudomonas sp. WJ6 was isolated to degrade a wide range of n-alkanes and polycyclic aromatic hydrocarbons. Production of lipopeptide biosurfactant was observed in all biodegradable studies. These lipopeptides were purified and identified by C18 RP-HPLC system and electrospray ionization-mass spectrometry. Results of structural analysis showed that these lipopeptides generated from different hydrocarbons were classified to be surfactin, fengycin and lichenysin. Heavy-oil sludge washing experiments demonstrated that lipopeptides produced by Pseudomonas sp. WJ6 have 92.46% of heavy-oil washing efficiency. The obtained results indicate that this novel bacterial strain and its lipopeptides have great potentials in the environmental remediation and petroleum recovery.

  2. Purification and properties of ferredoxinNAP, a component of naphthalene dioxygenase from Pseudomonas sp. strain NCIB 9816.

    PubMed Central

    Haigler, B E; Gibson, D T

    1990-01-01

    One of the three components of the naphthalene dioxygenase occurring in induced cells of Pseudomonas sp. strain NCIB 9816 has been purified to homogeneity. The protein contained 2 g-atoms each of iron and acid-labile sulfur and had an apparent molecular weight of 13,600. The evidence indicates that it is a ferredoxin-type protein that functions as an intermediate electron transfer protein in naphthalene dioxygenase activity. PMID:2294093

  3. Dissimilar plasmids isolated from Pseudomonas diminuta MG and a Flavobacterium sp. (ATCC 27551) contain identical opd genes.

    PubMed

    Harper, L L; McDaniel, C S; Miller, C E; Wild, J R

    1988-10-01

    The opd (organophosphate-degrading) gene derived from a 43-kilobase-pair plasmid (pSM55) of a Flavobacterium sp. (ATCC 27551) has a sequence identical to that of the plasmid-borne gene of Pseudomonas diminuta. Hybridization studies with DNA fragments obtained by restriction endonuclease digestion of plasmid DNAs demonstrated that the identical opd sequences were encoded on dissimilar plasmids from the two sources.

  4. Dissimilar plasmids isolated from Pseudomonas diminuta MG and a Flavobacterium sp. (ATCC 27551) contain identical opd genes.

    PubMed Central

    Harper, L L; McDaniel, C S; Miller, C E; Wild, J R

    1988-01-01

    The opd (organophosphate-degrading) gene derived from a 43-kilobase-pair plasmid (pSM55) of a Flavobacterium sp. (ATCC 27551) has a sequence identical to that of the plasmid-borne gene of Pseudomonas diminuta. Hybridization studies with DNA fragments obtained by restriction endonuclease digestion of plasmid DNAs demonstrated that the identical opd sequences were encoded on dissimilar plasmids from the two sources. Images PMID:3202637

  5. Pseudomonas linyingensis sp. nov.: a novel bacterium isolated from wheat soil subjected to long-term herbicides application.

    PubMed

    He, Wei-Hong; Wang, Ya-Nan; Du, Xun; Zhou, Yang; Jia, Bin; Bian, Jiang; Liu, Shuang-Jiang; Chen, Guo-Can

    2012-11-01

    A strain of genus Pseudomonas, LYBRD3-7(T) was isolated from long-term sulfonylurea herbicides applied wheat-field soil in Linying located in Henan province of China. This strain is a strictly aerobic and Gram-negative short rod-shaped bacterium with single flagellum. Phylogenetic evaluation based on 16S rRNA gene sequence analysis placed this isolate as a member of Pseudomonas, and most closely to Pseudomonas tuomuerensis CGMCC 1.1365(T) (97.1 %) and P. alcaligenes IAM12411(T) (97.1 %). Morphological characters and chemotaxonomic data confirmed the affiliation of strain LYBRD3-7(T) to the genus Pseudomonas. The results of phylogenetic analysis, physiological and biochemical studies, and DNA-DNA hybridization allowed the differentiation of genotype and phenotype between strain LYBRD3-7(T) and the phylogenetic closest species with valid names. The name proposed for the new species is Pseudomonas linyingensis sp. nov. The type strain is LYBRD3-7(T) (=CGMCC 1.10701(T ) =LMG 25967(T)).

  6. Decolorization and detoxification of Congo red and textile industry effluent by an isolated bacterium Pseudomonas sp. SU-EBT.

    PubMed

    Telke, Amar A; Joshi, Swati M; Jadhav, Sheetal U; Tamboli, Dhawal P; Govindwar, Sanjay P

    2010-04-01

    The 16S rRNA sequence and biochemical characteristics revealed the isolated organism as Pseudomonas sp. SU-EBT. This strain showed 97 and 90% decolorization of a recalcitrant dye, Congo red (100 mg l(-1)) and textile industry effluent with 50% reduction in COD within 12 and 60 h, respectively. The optimum pH and temperature for the decolorization was 8.0 and 40 degrees C, respectively. Pseudomonas sp. SU-EBT was found to tolerate the dye concentration up to 1.0 g l(-1). Significant induction in the activity of intracellular laccase suggested its involvement in the decolorization of Congo red. The metabolites formed after decolorization of Congo red, such as p-dihydroxy biphenyl, 8-amino naphthol 3-sulfonic acid and 3-hydroperoxy 8-nitrosonaphthol were characterized using FTIR and GC-MS. Phytotoxicity study revealed nontoxic nature of the degradation metabolites to Sorghum bicolor, Vigna radiata, Lens culinaris and Oryza sativa plants as compared to Congo red and textile industry effluent. Pseudomonas sp. SU-EBT decolorized several individual textile dyes, dye mixtures and textile industry effluent, thus it is a useful strain for the development of effluent treatment methods in textile processing industries.

  7. Insecticidal activity of rhamnolipid isolated from pseudomonas sp. EP-3 against green peach aphid (Myzus persicae).

    PubMed

    Kim, Seul Ki; Kim, Young Cheol; Lee, Sunwoo; Kim, Jin Cheol; Yun, Mi Young; Kim, In Seon

    2011-02-09

    Microorganisms capable of growth on oils are potential sources of biopesticides, as they produce complex molecules such as biosurfactants and lipopeptides. These molecules have antimicrobial activity against plant pathogens, but few data are available on their insecticidal activity. The present study describes the insecticidal activity of a rhamnolipid isolated from diesel oil-degrading Pseudomonas sp. EP-3 (EP-3). The treatment of cell-free supernatants of EP-3 grown on glucose-mineral medium for 96 h led to > 80% mortality of aphids (Myzus persicae) within 24 h. Bioassay-guided chromatography coupled with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MADLDI-TOF MS) and (¹H, ¹³C) nuclear magnetic resonance (NMR) analyses was employed to isolate and identify the EP-3 insecticidal metabolites. Dirhamnolipid, with molecular formulas of C₃₂H₅₈O₁₃ and C₃₄H₆₂O₁₃, was identified as a main metabolite exhibiting insecticidal activity against aphids. Dirhamnolipid showed a dose-dependent mortality against aphids, producing about 50% mortality at 40 μg/mL and 100% mortality at 100 μg/mL. Microscopy analyses of aphids treated with dirhamnolipid revealed that dirhamnolipid caused insect death by affecting cuticle membranes. This is the first report of rhamnolipid as an insecticidal metabolite against M. persicae. Rhamnolipid shows potential for use as a pesticide to control agricultural pests.

  8. Degradation of chloronitrobenzenes by a coculture of Pseudomonas putida and a Rhodococcus sp.

    SciTech Connect

    Park, H.S.; Lim, S.J.; Chang, Y.K.; Kim, H.S.; Livingston, A.G.

    1999-03-01

    A single microorganism able to mineralize chloronitrobenzenes (CNBs) has not been reported, and degradation of CNBs of coculture of two microbial strains was attempted. Pseudomonas putida HS12 was first isolated by analogue enrichment culture using nitrobenzene (NB) as the substrate, and this strain was observed to possess a partial reductive pathway for the degradation of NB. From high-performance liquid chromatography-mass spectrometry and {sup 1}H nuclear magnetic resonance analyses, NB-grown cells of P. putida HS12 were found to convert 3- and 4-CNBs to the corresponding 5- and 4-chloro-2-hydroxyacetanilides, respectively, by partial reduction and subsequent acetylation. For the degradation of CNBs, Rhodococcus sp. strain HS51, which degrades 4- and 5-chloro-2-hydroxyacetanilides, was isolated and combined with P. putida HS12 to give a coculture. This coculture was confirmed to mineralize 3- and 4-CNBs in the presence of an additional carbon source. A degradation pathway for 3- and 4-CNBs by the two isolated strains was also proposed.

  9. Metabolism of dibenzofuran by pseudomonas sp. strain HH69 and the mixed culture HH27

    SciTech Connect

    Fortnagel, P.; Harms, H.; Wittich, R.M. ); Krohn, S.; Meyer, H.; Sinnwell, V.; Wilkes, H.; Francke, W. )

    1990-04-01

    A Pseudomonas sp. strain, HH69, and a mixed culture, designated HH27, were isolated by selective enrichment from soil samples. The pure strain and the mixed culture grew aerobically on dibenzofuran as the sole source of carbon and energy. Degradation proceeded via salicylic acid which was branched into the gentisic acid and the catechol pathway. Both salicylic acid and gentisic acid accumulated in the culture medium of strain HH69. The acids were slowly metabolized after growth ceased. The enzymes responsible for their metabolism showed relatively low activities. Besides the above-mentioned acids, 2-hydroxyacetophenone, benzopyran-4-one (chrome), several 2-substituted chroman-4-ones, and traces of the four isomeric monohydroxydibenzofurans were identified in the culture medium. 2,2{prime},3-Trihydroxybiphenyl was isolated from the medium of a dibenzofuran-converting mutant derived from parent strain HH69, which can no longer grow on dibenzofuran. This gives evidence for a novel type of dioxygenases responsible for the attack on the biarylether structure of the dibenzofuran molecule. A meta-fission mechanism for cleavage of the dihydroxylated aromatic nucleus of 2,2{prime},3-trihydroxybiphenyl is suggested as the next enzymatic step in the degradative pathway.

  10. Characterization of a sodium dodecyl sulphate-degrading Pseudomonas sp. strain DRY15 from Antarctic soil.

    PubMed

    Halmi, M I E; Hussin, W S W; Aqlima, A; Syed, M A; Ruberto, L; MacCormack, W P; Shukor, M Y

    2013-11-01

    A bacterium capable of biodegrading surfactant sodium dodecyl sulphate (SDS) was isolated from Antarctic soil. The isolate was tentatively identified as Pseudomonas sp. strain DRY15 based on carbon utilization profiles using Biolog GN plates and partial 16S rDNA molecular phylogeny. Growth characteristic studies showed that the bacterium grew optimally at 10 degrees C, 7.25 pH, 1 g l(-1) SDS as a sole carbon source and 2 g l(-1) ammonium sulphate as nitrogen source. Growth was completely inhibited at 5 g l(-1) SDS. At a tolerable initial concentration of 2 g l(-1), approximately 90% of SDS was degraded after an incubation period of eight days. The best growth kinetic model to fit experimental data was the Haldane model of substrate inhibition with a correlation coefficient value of 0.97. The maximum growth rate was 0.372 hr(-1) while the saturation constant or half velocity constant (Ks) and inhibition constant (Ki), were 0.094% and 11.212 % SDS, respectively. Other detergent tested as carbon sources at 1 g l(-1) was Tergitol NP9, Tergitol 15S9, Witconol 2301 (methyl oleate), sodium dodecylbenzene sulfonate (SDBS), benzethonium chloride, and benzalkonium chloride showed Tergitol NP9, Tergitol 15S9, Witconol 2301 and the anionic SDBS supported growth with the highest growth exhibited by SDBS.

  11. Biodegradation of Phenanthrene by Pseudomonas sp. JPN2 and Structure-Based Degrading Mechanism Study.

    PubMed

    Jin, Jingnan; Yao, Jun; Zhang, Qingye

    2016-11-01

    The strain Pseudomonas sp. JPN2 had a high potential to degrade phenanthrene degrading 98.52 % of the initial amount of 100 mg L(-1) after 10 days incubation. The analysis of metabolites demonstrated that the cleavage of phenanthrene started at the C9 and C10 positions on the aromatic ring by the dioxygenation reaction, and then further degraded via a phthalate pathway. To understand the interaction between phenanthrene and the amino acid residues in the active site of the target enzyme, a molecular docking simulation was performed. The results showed that the distances of C9-O1 and C10-O2 atoms were 3.47 and 3.67 Å, respectively. The C9 and C10 positions of the phenanthrene ring are much closer to the dioxygen molecule in the active site relative to the other atoms. Therefore, the C9 and C10 positions are vulnerable to attack in the initial oxygenation process.

  12. Toluene and ethylbenzene oxidation by purified naphthalene dioxygenase from Pseudomonas sp. strain NCIB 9816-4.

    PubMed

    Lee, K; Gibson, D T

    1996-09-01

    Purified naphthalene dioxygenase (NDO) from Pseudomonas sp. strain NCIB 9816-4 oxidized toluene to benzyl alcohol and benzaldehyde by reactions involving benzylic monooxygenation and dioxygen-dependent alcohol oxidation, respectively. Xylene and nitrotoluene isomers were also oxidized to substituted benzyl alcohol and benzaldehyde derivatives. NDO oxidized ethylbenzene sequentially through (S)-1-phenethyl alcohol (77% enantiomeric excess) and acetophenone to 2-hydroxyacetophenone. In addition, NDO also oxidized ethylbenzene through styrene to (R)-1-phenyl-1,2-ethanediol (74% enantiomeric excess) by reactions involving desaturation and dihydroxylation, respectively. Isotope experiments with 18O2, H2 18O, and D2O suggest that 1-phenethyl alcohol is oxidized to acetophenone by a minor reaction involving desaturation followed by tautomerization. The major reaction in the conversion of 1-phenethyl alcohol and benzyl alcohol to acetophenone and benzaldehyde, respectively, probably involves monohydroxylation to form a gem-diol intermediate which stereospecifically loses the incoming hydroxyl group to leave the carbonyl product. These results are compared with similar reactions catalyzed by cytochrome P-450.

  13. Monooxygenase-mediated 1,2-dichloroethane degradation by Pseudomonas sp. strain DCA1

    SciTech Connect

    Hage, J.C.; Hartmans, S.

    1999-06-01

    A bacterial strain, designated Pseudomonas sp. strain DCA1, was isolated from a 1,2-dichloroethane (DCA)-degrading biofilm. Strain DCA1 utilizes DCA as the sole carbon and energy source and does not require additional organic nutrients, such as vitamins, for optimal growth. The affinity of strain DCA1 for DCA is very high, with a K{sub m} value below the detection limit of 0.5 {micro}M. Instead of a hydrolytic dehalogenation, as in other DCA utilizers, the first step in DCA degradation in strain DCA1 is an oxidation reaction. Oxygen and NAD(P)H are required for this initial step. Propene was converted to 1,2-epoxypropane by DCA-grown cells and competitively inhibited DCA degradation. The authors concluded that a monooxygenase is responsible for the first step in DCA degradation in strain DCA1. Oxidation of DCA probably results in the formation of the unstable intermediate 1,2-dichloroethanol, which spontaneously releases chloride, yielding chloroacetaldehyde. The DCA degradation pathway is strain DCA1 proceeds from chloroacetaldehyde via chloroacetic acid and presumably glycolic acid, which is similar to degradation routes observed in other DCA-utilizing bacteria.

  14. Degradation of Chloronitrobenzenes by a Coculture of Pseudomonas putida and a Rhodococcus sp.

    PubMed Central

    Park, Hee-Sung; Lim, Sung-Jin; Chang, Young Keun; Livingston, Andrew G.; Kim, Hak-Sung

    1999-01-01

    A single microorganism able to mineralize chloronitrobenzenes (CNBs) has not been reported, and degradation of CNBs by coculture of two microbial strains was attempted. Pseudomonas putida HS12 was first isolated by analogue enrichment culture using nitrobenzene (NB) as the substrate, and this strain was observed to possess a partial reductive pathway for the degradation of NB. From high-performance liquid chromatography-mass spectrometry and 1H nuclear magnetic resonance analyses, NB-grown cells of P. putida HS12 were found to convert 3- and 4-CNBs to the corresponding 5- and 4-chloro-2-hydroxyacetanilides, respectively, by partial reduction and subsequent acetylation. For the degradation of CNBs, Rhodococcus sp. strain HS51, which degrades 4- and 5-chloro-2-hydroxyacetanilides, was isolated and combined with P. putida HS12 to give a coculture. This coculture was confirmed to mineralize 3- and 4-CNBs in the presence of an additional carbon source. A degradation pathway for 3- and 4-CNBs by the two isolated strains was also proposed. PMID:10049867

  15. Simultaneous heterotrophic nitrification and aerobic denitrification by the marine origin bacterium Pseudomonas sp. ADN-42.

    PubMed

    Jin, Ruofei; Liu, Tianqi; Liu, Guangfei; Zhou, Jiti; Huang, Jianyu; Wang, Aijie

    2015-02-01

    Recent research has highlighted the existence of some bacteria that are capable of performing heterotrophic nitrification and have a phenomenal ability to denitrify their nitrification products under aerobic conditions. A high-salinity-tolerant strain ADN-42 was isolated from Hymeniacidon perleve and found to display high heterotrophic ammonium removal capability. This strain was identified as Pseudomonas sp. via 16S rRNA gene sequence analysis. Gene cloning and sequencing analysis indicated that the bacterial genome contains N2O reductase function (nosZ) gene. NH3-N removal rate of ADN-42 was very high. And the highest removal rate was 6.52 mg/L · h in the presence of 40 g/L NaCl. Under the condition of pure oxygen (DO >8 mg/L), NH3-N removal efficiency was 56.9 %. Moreover, 38.4 % of oxygen remained in the upper gas space during 72 h without greenhouse gas N2O production. Keeping continuous and low level of dissolved oxygen (DO <3 mg/L) was helpful for better denitrification performance. All these results indicated that the strain has heterotrophic nitrification and aerobic denitrification abilities, which guarantee future application in wastewater treatment.

  16. Statistical media design for efficient polyhydroxyalkanoate production in Pseudomonas sp. MNNG-S.

    PubMed

    Saranya, V; Rajeswari, V; Abirami, P; Poornimakkani, K; Suguna, P; Shenbagarathai, R

    2016-07-03

    Polyhydroxyalkanoate (PHA) is a promising polymer for various biomedical applications. There is a high need to improve the production rate to achieve end use. When a cost-effective production was carried out with cheaper agricultural residues like molasses, traces of toxins were incorporated into the polymer, which makes it unfit for biomedical applications. On the other hand, there is an increase in the popularity of using chemically defined media for the production of compounds with biomedical applications. However, these media do not exhibit favorable characteristics such as efficient utilization at large scale compared to complex media. This article aims to determine the specific nutritional requirement of Pseudomonas sp. MNNG-S for efficient production of polyhydroxyalkanoate. Response surface methodology (RSM) was used in this study to statistically design for PHA production based on the interactive effect of five significant variables (sucrose; potassium dihydrogen phosphate; ammonium sulfate; magnesium sulfate; trace elements). The interactive effects of sucrose with ammonium sulfate, ammonium sulfate with combined potassium phosphate, and trace element with magnesium sulfate were found to be significant (p < .001). The optimization approach adapted in this study increased the PHA production more than fourfold (from 0.85 g L(-1) to 4.56 g L(-1)).

  17. Oxidation of naphthalene by a multicomponent enzyme system from Pseudomonas sp. strain NCIB 9816.

    PubMed Central

    Ensley, B D; Gibson, D T; Laborde, A L

    1982-01-01

    The initial reactions in the oxidation of naphthalene by Pseudomonas sp. strain NCIB 9816 involves the enzymatic incorporation of one molecule of oxygen into the aromatic nucleus to form (+)-cis-(1R,2S)-dihydroxy-1,2-dihydronaphthalene. The enzyme catalyzing this reaction, naphthalene dioxygenase, was resolved into three protein components, designated A, B, and C, by DEAE-cellulose chromatography. Incubation of naphthalene with components A, B, and C in the presence of NADH resulted in the formation of (+)-cis-(1R,2S)-dihydroxy-1,2-dihydronaphthalene. The ratio of oxygen and NADH utilization to product formation was 1:1:1. NADPH also served as an electron donor for naphthalene oxygenation. However, its activity was less than 50% of that observed with NADH. Component A showed NAD(P)H-cytochrome c reductase activity which was stimulated by the addition of flavin adenine dinucleotide and flavin mononucleotide. A similar stimulation was observed when these flavin nucleotides were added to the naphthalene dioxygenase assay system. These preliminary observations indicate that naphthalene dioxygenase has properties in common with both monooxygenase and dioxygenase multicomponent enzyme systems. Images PMID:7037744

  18. A specific antimicrobial protein CAP-1 from Pseudomonas sp. isolated from the jellyfish Cyanea capillata.

    PubMed

    Yin, Manman; Liu, Dan; Xu, Feng; Xiao, Liang; Wang, Qianqian; Wang, Beilei; Chang, Yinlong; Zheng, Jiemin; Tao, Xia; Liu, Guoyan; Zhang, Liming

    2016-01-01

    A bacterium strain, designated as CMF-2, was isolated from the jellyfish Cyanea capillata and its culture supernatant exhibited a significant antimicrobial activity. The strain CMF-2 was identified as Pseudomonas sp. based on the morphological, biochemical and physiological characteristics as well as 16S rRNA sequence analysis. In this study, an antimicrobial protein, named as CAP-1, was isolated from the culture of CMF-2 through ammonium sulfate precipitation and gel filtration chromatography. According to the result of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), a major band indicated that the antimicrobial protein had a molecular mass of about 15 kDa, and it was identified as a hypothetical protein by MALDI-TOF-MS analysis and Mascot searching. CAP-1 displayed a broad antimicrobial spectrum against the indicator bacteria and fungus, including Staphylococcus aureus, Escherichia coli, Bacillus subtilis and Candida albicans, especially some marine-derived microorganisms such as Vibrio vulnificus, Vibrio alginolyticus, Vibrio parahaemolyticus, Vibrio cholera, and Vibrio anguillarum, but showed little impact on tumor cells and normal human cells. The protein CAP-1 remained a stable antimicrobial activity in a wide range of temperature (20-80°C) and pH (2-10) conditions. These results suggested that CAP-1 might have a specific antimicrobial function not due to cytotoxicity.

  19. Response surface optimization for efficient dye removal by isolated strain Pseudomonas sp.

    NASA Astrophysics Data System (ADS)

    Senthilkumar, Shanmugam; Perumalsamy, Muthiah; Prabhuy, Harinarayan Janardhana; AhmedBasha, Chiya; Anantharaman, Narayan

    2012-09-01

    Response surface methodology (RSM) involving the central composite design (CCD) was employed to optimize three important process variables for the decolourization of synthetic dye solutions containing Remazol Turquoise Blue (RTB) and Reactive Black 5 (RB5) with isolated bacterial strain Pseudomonas sp. The interaction between three variables i.e. Initial concentration of dye, carbon source and nitrogen source were studied and modeled. According to the Analysis of variance (ANOVA) results the predicted results were found to be in good agreement with experimental results ( R 2: 0.9726; Adj R 2: 0.9480 for RTB and R 2: 0.9789; Adj R 2: 0.9750 for RB5) which indicated excellent evaluation of experimental data from the second order polynomial regression model. Mathematical models were developed by the proposed system, for each process variable showed the effect of each factor and their interactions on biodecolourization process. The optimum concentrations of Dye, Carbon source, and Nitrogen source were found to be 20 mgL-1, 1.5 g/L and 1.5 g/L, respectively for RTB and RB5 to obtain maximum dye removing capacity. Predicted values were validated with experimental results, which indicated appropriateness of the employed model and the success of RSM.

  20. Response surface optimization for efficient dye removal by isolated strain Pseudomonas sp.

    NASA Astrophysics Data System (ADS)

    Senthilkumar, Shanmugam; Perumalsamy, Muthiah; Prabhuy, Harinarayan; AhmedBasha, Chiya; Anantharaman, Narayan

    2012-09-01

    Response surface methodology (RSM) involving the central composite design (CCD) was employed to optimize three important process variables for the decolourization of synthetic dye solutions containing Remazol Turquoise Blue (RTB) and Reactive Black 5 (RB5) with isolated bacterial strain Pseudomonas sp. The interaction between three variables i.e. Initial concentration of dye, carbon source and nitrogen source were studied and modeled. According to the Analysis of variance (ANOVA) results the predicted results were found to be in good agreement with experimental results (R 2: 0.9726; Adj R 2: 0.9480 for RTB and R 2: 0.9789; Adj R 2: 0.9750 for RB5) which indicated excellent evaluation of experimental data from the second order polynomial regression model. Mathematical models were developed by the proposed system, for each process variable showed the effect of each factor and their interactions on biodecolourization process. The optimum concentrations of Dye, Carbon source, and Nitrogen source were found to be 20 mgL-1, 1.5 g/L and 1.5 g/L, respectively for RTB and RB5 to obtain maximum dye removing capacity. Predicted values were validated with experimental results, which indicated appropriateness of the employed model and the success of RSM.

  1. Isolation and characterization of Pseudomonas sp. CBW capable of degrading carbendazim.

    PubMed

    Fang, Hua; Wang, Yiqi; Gao, Chunming; Yan, Hu; Dong, Bin; Yu, Yunlong

    2010-11-01

    With the intensive application of carbendazim in greenhouse production of vegetables and the production of medicinal herbs, there is an increasing need to find a way to remediate carbendazim-contaminated soil. A bacterial stain capable of utilizing carbendazim as the sole source of carbon and energy was isolated from soil. The isolate was designated CBW and identified as a member of Pseudomonas sp. based on its colony morphology, 16S rRNA gene sequencing and Biolog analysis. About 87.1 and 99.1% of carbendazim at concentrations of 1.0 and 10.0 mg l(-1) in mineral salts medium were removed by the isolate CBW after incubation for 3 days, respectively. The optimal pH value for the isolate CBW to degrade carbendazim was 7.0. The degradation rate of carbendazim by the isolate CBW was found to increase slightly with temperature. According to the metabolites detected and identified in the present study, it was proposed that carbendazim was first converted to 2-aminobenzimidazole, which was then transformed to 2-hydroxybenzimidazole, 1,2-diaminobenzene, catechol, and finally to carbon dioxide. The results indicate that the isolate CBW is a new bacterial resource for biodegrading carbendazim and might be used for bioremediation of sites heavily contaminated by carbendazim and its derivatives.

  2. Genome mining and metabolic profiling of the rhizosphere bacterium Pseudomonas sp. SH-C52 for antimicrobial compounds

    PubMed Central

    Van Der Voort, Menno; Meijer, Harold J. G.; Schmidt, Yvonne; Watrous, Jeramie; Dekkers, Ester; Mendes, Rodrigo; Dorrestein, Pieter C.; Gross, Harald; Raaijmakers, Jos M.

    2015-01-01

    The plant microbiome represents an enormous untapped resource for discovering novel genes and bioactive compounds. Previously, we isolated Pseudomonas sp. SH-C52 from the rhizosphere of sugar beet plants grown in a soil suppressive to the fungal pathogen Rhizoctonia solani and showed that its antifungal activity is, in part, attributed to the production of the chlorinated 9-amino-acid lipopeptide thanamycin (Mendes et al., 2011). To get more insight into its biosynthetic repertoire, the genome of Pseudomonas sp. SH-C52 was sequenced and subjected to in silico, mutational and functional analyses. The sequencing revealed a genome size of 6.3 Mb and 5579 predicted ORFs. Phylogenetic analysis placed strain SH-C52 within the Pseudomonas corrugata clade. In silico analysis for secondary metabolites revealed a total of six non-ribosomal peptide synthetase (NRPS) gene clusters, including the two previously described NRPS clusters for thanamycin and the 2-amino acid antibacterial lipopeptide brabantamide. Here we show that thanamycin also has activity against an array of other fungi and that brabantamide A exhibits anti-oomycete activity and affects phospholipases of the late blight pathogen Phytophthora infestans. Most notably, mass spectrometry led to the discovery of a third lipopeptide, designated thanapeptin, with a 22-amino-acid peptide moiety. Seven structural variants of thanapeptin were found with varying degrees of activity against P. infestans. Of the remaining four NRPS clusters, one was predicted to encode for yet another and unknown lipopeptide with a predicted peptide moiety of 8-amino acids. Collectively, these results show an enormous metabolic potential for Pseudomonas sp. SH-C52, with at least three structurally diverse lipopeptides, each with a different antimicrobial activity spectrum. PMID:26217324

  3. Atrazine chlorohydrolase from Pseudomonas sp. strain ADP: gene sequence, enzyme purification, and protein characterization.

    PubMed Central

    de Souza, M L; Sadowsky, M J; Wackett, L P

    1996-01-01

    Pseudomonas sp. strain ADP metabolizes atrazine to carbon dioxide and ammonia via the intermediate hydroxyatrazine. The genetic potential to produce hydroxyatrazine was previously attributed to a 1.9-kb AvaI DNA fragment from strain ADP (M. L. de Souza, L. P. Wackett, K. L. Boundy-Mills, R. T. Mandelbaum, and M. J. Sadowsky, Appl. Environ. Microbiol. 61:3373-3378, 1995). In this study, sequence analysis of the 1.9-kb AvaI fragment indicated that a single open reading frame, atzA, encoded an activity transforming atrazine to hydroxyatrazine. The open reading frame for the chlorohydrolase was determined by sequencing to be 1,419 nucleotides and encodes a 473-amino-acid protein with a predicted subunit molecular weight of 52,421. The deduced amino acid sequence matched the first 10 amino acids determined by protein microsequencing. The protein AtzA was purified to homogeneity by ammonium sulfate precipitation and anion-exchange chromatography. The subunit and holoenzyme molecular weights were 60,000 and 245,000 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gel filtration chromatography, respectively. The purified enzyme in H2(18)O yielded [18O]hydroxyatrazine, indicating that AtzA is a chlorohydrolase and not an oxygenase. The most related protein sequence in GenBank was that of TrzA, 41% identity, from Rhodococcus corallinus NRRL B-15444R. TrzA catalyzes the deamination of melamine and the dechlorination of deethylatrazine and desisopropylatrazine but is not active with atrazine. AtzA catalyzes the dechlorination of atrazine, simazine, and desethylatrazine but is not active with melamine, terbutylazine, or desethyldesisopropylatrazine. Our results indicate that AtzA is a novel atrazine-dechlorinating enzyme with fairly restricted substrate specificity and contributes to the microbial hydrolysis of atrazine to hydroxyatrazine in soils and groundwater. PMID:8759853

  4. Characterisation of a cold adapted esterase and mutants from a psychotolerant Pseudomonas sp. strain.

    PubMed

    Dong, Juan; Gasmalla, Mohammed A A; Zhao, Wei; Sun, Jingtao; Liu, Wenyu; Wang, Mingming; Han, Liang; Yang, Ruijin

    2016-07-13

    A cold-adapted esterase-producing strain named T1-39 was isolated from Glacier No.1, Tianshan, China, and identified as Pseudomonas sp. from 16S rRNA sequence analysis. The esterase (EstT1-39) secreted by this strain preferentially hydrolyzed esters of glycerol with short- and medium-chain fatty acids. Mutants of T1-39 were generated by the atmospheric and room-temperature plasma (ARTP) method and screened for enhanced esterase activity. Among all the mutants, strain TB11 had 4.45-fold higher esterase productivity than T1-39, with high genetic stability over 10 generations of continuous cultivation. Maximum activity of EstT1-39 and EstTB11 was observed at 30°C, pH 9.0 and 25°C, pH 8.5, respectively. EstTB11 was thermally more stable (50°C for 1 hour) and active over a broader pH range than EstT1-39. EstTB11 also retained 38% of its maximal activity at 0°C and was found to be able to hydrolyze milk fats into short- and medium-chain fatty acids at 4°C. The characteristics of EstT1-39 made it a cold-adapted enzyme and the EstTB11 from the mutant, with its higher activity at lower temperatures, may be suitable for the production of aromas and flavors in the dairy industry. This article is protected by copyright. All rights reserved.

  5. Cloning, expression and functional characterization of a novel trehalose synthase from marine Pseudomonas sp. P8005.

    PubMed

    Gao, Yun; Xi, Yue; Lu, Xiao-Ling; Zheng, Heng; Hu, Bo; Liu, Xiao-Yu; Jiao, Bing-Hua

    2013-11-01

    Trehalose synthase (TreS) catalyzes the reversible interconversion of maltose and trehalose. A novel treS gene with a length of 3,369 bp, encoding a protein of 1,122 amino acid residues with a predicted molecular mass of 126 kDa, was cloned from a marine Pseudomonas sp. P8005 (CCTCC: M2010298) and expressed in Escherichia coli. The amino acid sequence identities between this novel TreS and other reported TreS is relatively low. The purified recombinant TreS showed an optimum pH and temperature of 7.2 and 37 °C, respectively. The enzyme displayed a high conversion rate (70 %) of maltose to trehalose during equilibrium and had a higher catalytic efficiency (k cat/K m) for maltose than for trehalose, suggesting its application in the production of trehalose. In addition to maltose and trehalose, this enzyme can also act on sucrose, although this activity is relatively low. Mutagenesis studies demonstrated that enzymatic activity was reduced dramatically by individually substitution with alanine for D78, Y81, H121, D219, E261, H331 or D332, which implied that these residues might be important in P8005-TreS. Experiments using isotope-labeled substrates showed that [(2)H2]trehalose combined with unlabeled trehalose was converted to [(2)H2]maltose and maltose, but without any production of [(2)H]maltose or [(2)H]trehalose and with no incorporation of exogenous [(2)H7]glucose into the disaccharides during the conversion catalyzed by this enzyme. This finding indicated the involvement of an intramolecular mechanism in P8005-TreS catalyzing the reversible interconversion of maltose and trehalose.

  6. UO(2) 2+ speciation determines uranium toxicity and bioaccumulation in an environmental Pseudomonas sp. isolate.

    PubMed

    Vanengelen, Michael R; Field, Erin K; Gerlach, Robin; Lee, Brady D; Apel, William A; Peyton, Brent M

    2010-04-01

    In the present study, experiments were performed to investigate how representative cellulosic breakdown products, when serving as growth substrates under aerobic conditions, affect hexavalent uranyl cation (UO(2) (2+)) toxicity and bioaccumulation within a Pseudomonas sp. isolate (designated isolate A). Isolate A taken from the Cold Test Pit South (CTPS) region of the Idaho National Laboratory (INL), Idaho Falls, ID, USA. The INL houses low-level uranium-contaminated cellulosic material and understanding how this material, and specifically its breakdown products, affect U-bacterial interactions is important for understanding UO(2) (2+) fate and mobility. Toxicity was modeled using a generalized Monod expression. Butyrate, dextrose, ethanol, and lactate served as growth substrates. The potential contribution of bicarbonate species present in high concentrations was also investigated and compared with toxicity and bioaccumulation patterns seen in low-bicarbonate conditions. Isolate A was significantly more sensitive to UO(2) (2+) and accumulated significantly more UO(2) (2+) in low-bicarbonate concentrations. In addition, UO(2) (2+) growth inhibition and bioaccumulation varied depending on the growth substrate. In the presence of high bicarbonate concentrations, sensitivity to UO(2) (2+) inhibition was greatly mitigated, and did not vary between the four substrates tested. The extent of UO(2) (2+) accumulation was also diminished. The observed patterns were related to UO(2) (2+) aqueous complexation, as predicted by MINTEQ (ver. 2.52) (Easton, PA, USA). In the low- bicarbonate medium, the presence of positively charged and unstable UO(2) (2+)-hydroxide complexes explained both the greater sensitivity of isolate A to UO(2) (2+), and the ability of isolate A to accumulate significant amounts of UO(2) (2+). The exclusive presence of negatively charged and stable UO(2) (2+)-carbonate complexes in the high bi-carbonate medium explained the diminished sensitivity of

  7. Uptake of radioiodide by Paenibacillus sp., Pseudomonas sp., Burkholderia sp. and Rhodococcus sp. isolated from a boreal nutrient-poor bog.

    PubMed

    Lusa, Merja; Lehto, Jukka; Aromaa, Hanna; Knuutinen, Jenna; Bomberg, Malin

    2016-06-01

    Radionuclides, like radioiodine ((129)I), may escape deep geological nuclear waste repositories and migrate to the surface ecosystems. In surface ecosystems, microorganisms can affect their movement. Iodide uptake of six bacterial strains belonging to the genera Paenibacillus, Pseudomonas, Burkholderia and Rhodococcus isolated from an acidic boreal nutrient-poor bog was tested. The tests were run in four different growth media at three temperatures. All bacterial strains removed iodide from the solution with the highest efficiency shown by one of the Paenibacillus strains with >99% of iodide removed from the solution in one of the used growth media. Pseudomonas, Rhodococcus and one of the two Paenibacillus strains showed highest iodide uptake in 1% yeast extract with maximum values for the distribution coefficient (Kd) ranging from 90 to 270L/kg DW. The Burkholderia strain showed highest uptake in 1% Tryptone (maximum Kd 170L/kg DW). The Paenibacillus strain V0-1-LW showed exceptionally high uptake in 0.5% peptone +0.25% yeast extract broth (maximum Kd>1,000,000L/kg DW). Addition of 0.1% glucose to the 0.5% peptone +0.25% yeast extract broth reduced iodide uptake at 4°C and 20°C and enhanced iodide uptake at 37°C compared to the uptake without glucose. This indicates that the uptake of glucose and iodide may be competing processes in these bacteria. We estimated that in in situ conditions of the bog, the bacterial uptake of iodide accounts for approximately 0.1%-0.3% of the total sorption of iodide in the surface, subsurface peat, gyttja and clay layers.

  8. Phosphatidylcholine synthesis is essential for HrpZ harpin secretion in plant pathogenic Pseudomonas syringae and non-pathogenic Pseudomonas sp. 593.

    PubMed

    Xiong, Min; Long, Deliang; He, Huoguang; Li, Yang; Li, Yadong; Wang, Xingguo

    2014-01-01

    Pseudomonas syringae pv. syringae van Hall is important phytopathogenic bacterium of stone fruit trees, and able to elicit hypersensitive response (HR) in nonhost plants. The HrpZ, secreted via type III secretion system (T3SS) to the extracellular space of the plant, is a T3SS-dependent protein and a sole T3SS effector able to induce the host defense response outside host cells. We deleted the phosphatidylcholine synthase gene (pcs) of P. syringae pv. syringae van Hall CFCC 1336, and found that the 1336 pcs(-) mutant was unable to synthesize phosphatidylcholine and elicit a typical HR in soybean. Further studies showed that the 1336 pcs(-) mutant was unable to secrete HrpZ harpin but could express HrpZ protein in cytoplasm as effectively as the wild type. To confirm if phosphatidylcholine affects HrpZ harpin secretion, we introduced the hrpZ gene into the soil-dwelling bacterium Pseudomonas sp. 593 and the 593 pcs(-) mutant, which were unable to express HrpZ harpin and elicit HR in tobacco or soybean. Western blotting and HR assay showed that the 593H not only secreted HrpZ harpin but also caused a strong HR in tobacco and soybean. In contrast, the 593 pcs(-)H only expressed HrpZ protein in its cytoplasm at the wild type level, but did not secrete HrpZ harpin or elicit HR reaction. Our results demonstrate that phosphatidylcholine is essential for the secretion of HrpZ harpin in P. syringae pv. syringae van Hall and other Pseudomonas strains.

  9. Purification and characterization of allophanate hydrolase (AtzF) from Pseudomonas sp. strain ADP.

    PubMed

    Shapir, Nir; Sadowsky, Michael J; Wackett, Lawrence P

    2005-06-01

    AtzF, allophanate hydrolase, is a recently discovered member of the amidase signature family that catalyzes the terminal reaction during metabolism of s-triazine ring compounds by bacteria. In the present study, the atzF gene from Pseudomonas sp. strain ADP was cloned and expressed as a His-tagged protein, and the protein was purified and characterized. AtzF had a deduced subunit molecular mass of 66,223, based on the gene sequence, and an estimated holoenzyme molecular mass of 260,000. The active protein did not contain detectable metals or organic cofactors. Purified AtzF hydrolyzed allophanate with a k(cat)/K(m) of 1.1 x 10(4) s(-1) M(-1), and 2 mol of ammonia was released per mol allophanate. The substrate range of AtzF was very narrow. Urea, biuret, hydroxyurea, methylcarbamate, and other structurally analogous compounds were not substrates for AtzF. Only malonamate, which strongly inhibited allophanate hydrolysis, was an alternative substrate, with a greatly reduced k(cat)/K(m) of 21 s(-1) M(-1). Data suggested that the AtzF catalytic cycle proceeds through a covalent substrate-enzyme intermediate. AtzF reacts with malonamate and hydroxylamine to generate malonohydroxamate, potentially derived from hydroxylamine capture of an enzyme-tethered acyl group. Three putative catalytically important residues, one lysine and two serines, were altered by site-directed mutagenesis, each with complete loss of enzyme activity. The identity of a putative serine nucleophile was probed using phenyl phosphorodiamidate that was shown to be a time-dependent inhibitor of AtzF. Inhibition was due to phosphoroamidation of Ser189 as shown by liquid chromatography/matrix-assisted laser desorption ionization mass spectrometry. The modified residue corresponds in sequence alignments to the nucleophilic serine previously identified in other members of the amidase signature family. Thus, AtzF affects the cleavage of three carbon-to-nitrogen bonds via a mechanism similar to that of

  10. Purification and Characterization of Allophanate Hydrolase (AtzF) from Pseudomonas sp. Strain ADP

    PubMed Central

    Shapir, Nir; Sadowsky, Michael J.; Wackett, Lawrence P.

    2005-01-01

    AtzF, allophanate hydrolase, is a recently discovered member of the amidase signature family that catalyzes the terminal reaction during metabolism of s-triazine ring compounds by bacteria. In the present study, the atzF gene from Pseudomonas sp. strain ADP was cloned and expressed as a His-tagged protein, and the protein was purified and characterized. AtzF had a deduced subunit molecular mass of 66,223, based on the gene sequence, and an estimated holoenzyme molecular mass of 260,000. The active protein did not contain detectable metals or organic cofactors. Purified AtzF hydrolyzed allophanate with a kcat/Km of 1.1 × 104 s−1 M−1, and 2 mol of ammonia was released per mol allophanate. The substrate range of AtzF was very narrow. Urea, biuret, hydroxyurea, methylcarbamate, and other structurally analogous compounds were not substrates for AtzF. Only malonamate, which strongly inhibited allophanate hydrolysis, was an alternative substrate, with a greatly reduced kcat/Km of 21 s−1 M−1. Data suggested that the AtzF catalytic cycle proceeds through a covalent substrate-enzyme intermediate. AtzF reacts with malonamate and hydroxylamine to generate malonohydroxamate, potentially derived from hydroxylamine capture of an enzyme-tethered acyl group. Three putative catalytically important residues, one lysine and two serines, were altered by site-directed mutagenesis, each with complete loss of enzyme activity. The identity of a putative serine nucleophile was probed using phenyl phosphorodiamidate that was shown to be a time-dependent inhibitor of AtzF. Inhibition was due to phosphoroamidation of Ser189 as shown by liquid chromatography/matrix-assisted laser desorption ionization mass spectrometry. The modified residue corresponds in sequence alignments to the nucleophilic serine previously identified in other members of the amidase signature family. Thus, AtzF affects the cleavage of three carbon-to-nitrogen bonds via a mechanism similar to that of enzymes

  11. A newly isolated Pseudomonas sp., epibiotic on the seaweed, Padina tetrastromatica, off Southeastern Coast of India, reveals antibacterial action.

    PubMed

    Ravisankar, Aishwarya; Gnanambal, Mary Elizabeth K; Sundaram, Lakshmi R

    2013-12-01

    Epibionts from the red (Hypnea valentiae) and brown seaweeds (Padina tetrastromatica) were rapidly isolated on Zobell agar medium. All the isolates from both the seaweeds (76 numbers) were tested against five human pathogens which were resistant to at least one of the commercially available antibiotics at a minimal concentration of 10 mg. The most antibiotic productive isolate (PT19) from Padina tetrastromatica was extracted and observed to inhibit Klebsiella pneumoniae and Pseudomonas aeruginosa with zone sizes of 15 and 10 mm radius, respectively, at a concentration of 300 μg. Further, a direct bioautography was done and an inhibition was witnessed against the aforementioned pathogens even at 2 μg concentration around three spots (R f values 0.6, 0.7, and 0.8). Preparative thin-layer chromatography yielded a yellow sticky compound (6 mg) which was identified as an alkaloid. The compound on reversed-phase high-pressure liquid chromatography analysis yielded two major and two minor peaks with retention times, 3.1, 4.2, 4.7, and 4.9 min, respectively. The antibacterial compound was recorded 96.6 % pure, and the producer strain was identified as Pseudomonas sp. To our knowledge, we are the first to isolate and identify Pseudomonas from Padina tetrastromatica producing antibacterial alkaloids. This study will pave way for exploring more bacterial load from the said algal groups for bioactivities.

  12. Root colonization by Pseudomonas sp. DSMZ 13134 and impact on the indigenous rhizosphere bacterial community of barley.

    PubMed

    Buddrus-Schiemann, Katharina; Schmid, Michael; Schreiner, Karin; Welzl, Gerhard; Hartmann, Anton

    2010-08-01

    Over the last few decades, the ability of rhizosphere bacteria to promote plant growth has been considered to be of scientific, ecological, and economic interest. The properties and mechanisms of interaction of these root-colonizing bacteria have been extensively investigated, and plant protection agents that are based on these bacterial strains have been developed for agricultural applications. In the present study, the root colonization of barley by Pseudomonas sp. DSMZ 13134, that is contained in the commercially available plant protection agent Proradix, was examined using the fluorescence in situ hybridization method with oligonucleotide probes and specific gfp-tagging of the inoculant strain in combination with confocal laser scanning microscopy. In the first phase of root colonization, the inoculant strain competed successfully with seed and soil-borne bacteria (including Pseudomonads) for the colonization of the rhizoplane. Pseudomonas sp. DSMZ 13134 could be detected in all parts of the roots, although it did not belong to the dominant members of the root-associated bacterial community. Gfp-tagged cells were localized particularly in the root hair zone, and high cell densities were apparent on the root hair surface. To investigate the impact of the application of Proradix on the structure of the dominant root-associated bacterial community of barley, T-RFLP analyses were performed. Only a transient community effect was found until 3 weeks post-application.

  13. Biodegradation of benzalkonium chlorides singly and in mixtures by a Pseudomonas sp. isolated from returned activated sludge.

    PubMed

    Khan, Adnan Hossain; Topp, Edward; Scott, Andrew; Sumarah, Mark; Macfie, Sheila M; Ray, Madhumita B

    2015-12-15

    Bactericidal cationic surfactants such as quaternary ammonium compounds (QACs) are widely detected in the environment, and found at mg kg(-1) concentrations in biosolids. Although individual QACs are amenable to biodegradation, it is possible that persistence is increased for mixtures of QACs with varying structure. The present study evaluated the biodegradation of benzyl dimethyl dodecyl ammonium chloride (BDDA) singly and in the presence of benzyl dimethyl tetradecyl ammonium chloride (BDTA) using Pseudomonas sp., isolated from returned activated sludge. Growth was evaluated, as was biodegradation using (14)C and HPLC-MS methods. BDTA was more toxic to growth of Pseudomonas sp. compared to BDDA, and BDTA inhibited BDDA biodegradation. The benzyl ring of [U-(14)C-benzyl] BDDA was readily and completely mineralized. The detection of the transformation products benzyl methyl amine and dodecyl dimethyl amine in spent culture liquid was consistent with literature. Overall, this study demonstrates the antagonistic effect of interactions on biodegradation of two widely used QACs suggesting further investigation on the degradation of mixture of QACs in wastewater effluents and biosolids.

  14. Characterization of a newly isolated strain Pseudomonas sp. C27 for sulfide oxidation: Reaction kinetics and stoichiometry

    PubMed Central

    Xu, Xi-Jun; Chen, Chuan; Guo, Hong-liang; Wang, Ai-jie; Ren, Nan-qi; Lee, Duu-Jong

    2016-01-01

    Sulfide biooxidation by the novel sulfide-oxidizing bacteria Pseudomonas sp. C27, which could perform autotrophic and heterotrophic denitrification in mixotrophic medium, was studied in batch and continuous systems. Pseudomonas sp. C27 was able to oxidize sulfide at concentrations as high as 17.66 mM. Sulfide biooxidation occurred in two distinct stages, one resulting in the formation of sulfur with nitrate reduction to nitrite, followed by thiosulfate formation with nitrite reduction to N2. The composition of end-products was greatly impacted by the ratio of sulfide to nitrate initial concentrations. At a ratio of 0.23, thiosulfate represented 100% of the reaction products, while only 30% with a ratio of 1.17. In the continuous bioreactor, complete removal of sulfide was observed at sulfide concentration as high as 9.38 mM. Overall sulfide removal efficiency decreased continuously upon further increases in influent sulfide concentrations. Based on the experimental data kinetic parameter values were determined. The value of maximum specific growth rate, half saturation constant, decay coefficient, maintenance coefficient and yield were to be 0.11 h−1, 0.68 mM sulfide, 0.11 h−1, 0.21 mg sulfide/mg biomass h and 0.43 mg biomass/mg sulfide, respectively, which were close to or comparable with those reported in literature by other researches. PMID:26864216

  15. Molecular Cloning and Functional Expression of a Δ9- Fatty Acid Desaturase from an Antarctic Pseudomonas sp. A3

    PubMed Central

    Garba, Lawal; Mohamad Ali, Mohd Shukuri; Oslan, Siti Nurbaya; Rahman, Raja Noor Zaliha Raja Abd

    2016-01-01

    Fatty acid desaturase enzymes play an essential role in the synthesis of unsaturated fatty acids. Pseudomonas sp. A3 was found to produce a large amount of palmitoleic and oleic acids after incubation at low temperatures. Using polymerase Chain Reaction (PCR), a novel Δ9- fatty acid desaturase gene was isolated, cloned, and successfully expressed in Escherichia coli. The gene was designated as PA3FAD9 and has an open reading frame of 1,185 bp which codes for 394 amino acids with a predicted molecular weight of 45 kDa. The activity of the gene product was confirmed via GCMS, which showed a functional putative Δ9-fatty acid desaturase capable of increasing the total amount of cellular unsaturated fatty acids of the E. coli cells expressing the gene. The results demonstrate that the cellular palmitoleic acids have increased two-fold upon expression at 15°C using only 0.1 mM IPTG. Therefore, PA3FAD9 from Pseudomonas sp.A3 codes for a Δ9-fatty acid desaturase-like protein which was actively expressed in E. coli. PMID:27494717

  16. Enhanced cometabolic degradation of methyl tert-butyl ether by a Pseudomonas sp. strain grown on n-pentane

    NASA Astrophysics Data System (ADS)

    Li, S. S.; Wang, S.; Yan, W.

    2016-08-01

    When methyl tert-butyl ether (MTBE) is added as oxygenates it increases the octane number and decreases the release of nitric oxide from the incomplete combustion of reformulated gasoline. The extensive use of MTBE allowed it to be detectable as a pollutant in both ground-level and underground water worldwide. The present study focuses on the isolation and characterization of MTB-degrading microorganisms by cometabolism based on the results of growth on different carbon sources. It also focuses on the kinetic analysis and the continuous degradation of MTBE. A bacterial strain WL1 that can grow on both n-alkanes (C5-C8) and aromatics was isolated and named Pseudomonas sp. WL1 according to the 16S rDNA sequencing analysis. Strain WL1 could cometabolically degrade MTBE in the presence of n-alkanes with a desirable degradation rate. Diverse n-alkanes with different lengths of carbon chains showed significant influence on the degradation rate of MTBE and accumulation of tert-butyl alcohol (TBA). When strain WL1 cometabolically degraded MTBE in the presence of n-pentane, higher MTBE-degrading rate and lower TBA-accumulation were observed (Vmax = 38.1 nmol/min/mgprotei, Ks = 6.8 mmol/L). In the continuous degrading experiment, the removal efficiency of MTBE by Pseudomonas sp. WL1 did not show any obvious decrease after five subsequent additions.

  17. A transposable class I composite transposon carrying mph (methyl parathion hydrolase) from Pseudomonas sp. strain WBC-3.

    PubMed

    Wei, Min; Zhang, Jun-Jie; Liu, Hong; Wang, Shu-Jun; Fu, He; Zhou, Ning-Yi

    2009-03-01

    Pseudomonas sp. strain WBC-3 utilizes methyl parathion (O,O-dimethyl O-p-nitrophenol phosphorothioate) or para-nitrophenol as the sole source of carbon, nitrogen and energy. A gene encoding methyl parathion hydrolase (MPH) had been characterized previously and found to be located on a typical class I composite transposon that comprised IS6100 (Tnmph). In this study, the transposability of this transposon was confirmed by transposition assays in two distinct mating-out systems. Tnmph was demonstrated to transpose efficiently in a random manner in Pseudomonas putida PaW340 by Southern blot and in Ralstonia sp. U2 by sequence analysis of the Tnmph insertion sites, both exhibiting MPH activity. The linkage of the mph-like gene with IS6100, together with the transposability of Tnmph, as well as its capability to transpose in other phylogenetically divergent bacterial species, suggest that Tnmph may contribute to the wide distribution of mph-like genes and the adaptation of bacteria to organophosphorus compounds.

  18. Pesticide tolerant and phosphorus solubilizing Pseudomonas sp. strain SGRAJ09 isolated from pesticides treated Achillea clavennae rhizosphere soil.

    PubMed

    Rajasankar, R; Manju Gayathry, G; Sathiavelu, A; Ramalingam, C; Saravanan, V S

    2013-05-01

    In this study, an attempt was made to identify an effective phosphate solubilizing bacteria from pesticide polluted field soil. Based on the formation of solubilization halo on Pikovskaya's agar, six isolates were selected and screened for pesticide tolerance and phosphate (P) solubilization ability through liquid assay. The results showed that only one strain (SGRAJ09) obtained from Achillea clavennae was found to tolerate maximum level of the pesticides tested and it was phylogenetically identified as Pseudomonas sp. It possessed a wide range of pesticide tolerance, ranging from 117 μg mL(-1) for alphamethrin to 2,600 μg mL(-1) for endosulfan. The available P concentrations increased with the maximum and double the maximum dose of monocrotophos and imidacloprid, respectively. On subjected to FT-IR and HPLC analysis, the presence of organic acids functional group in the culture broth and the production of gluconic acid as dominant acid aiding the P solubilization were identified. On comparison with control broth, monocrotophos and imidacloprid added culture broth showed quantitatively high organic acids production. In addition to gluconic acid production, citric and acetic acids were also observed in the pesticide amended broth. Furthermore, the Pseudomonas sp. strain SGRAJ09 possessed all the plant growth promoting traits tested. In presence of monocrotophos and imidacloprid, its plant growth promoting activities were lower than that of the pesticides unamended treatment.

  19. The chitinase C gene PsChiC from Pseudomonas sp. and its synergistic effects on larvicidal activity

    PubMed Central

    Zhong, Wanfang; Ding, Shaojun; Guo, Huifang

    2015-01-01

    Pseudomonas sp. strain TXG6-1, a chitinolytic gram-negative bacterium, was isolated from a vegetable field in Taixing city, Jiangsu Province, China. In this study, a Pseudomonas chitinase C gene (PsChiC) was isolated from the chromosomal DNA of this bacterium using a pair of specific primers. The PsChiC gene consisted of an open reading frame of 1443 nucleotides and encoded 480 amino acid residues with a calculated molecular mass of 51.66 kDa. The deduced PsChiC amino acid sequence lacked a signal sequence and consisted of a glycoside hydrolase family 18 catalytic domain responsible for chitinase activity, a fibronectin type III-like domain (FLD) and a C-terminal chitin-binding domain (ChBD). The amino acid sequence of PsChiCshowed high sequence homology (> 95%) with chitinase C from Serratia marcescens. SDS-PAGE showed that the molecular mass of chitinase PsChiC was 52 kDa. Chitinase assays revealed that the chitobiosidase and endochitinase activities of PsChiCwere 51.6- and 84.1-fold higher than those of pET30a, respectively. Although PsChiC showed little insecticidal activity towards Spodoptera litura larvae, an insecticidal assay indicated that PsChiC increased the insecticidal toxicity of SpltNPV by 1.78-fold at 192 h and hastened death. These results suggest that PsChiC from Pseudomonas sp. could be useful in improving the pathogenicity of baculoviruses. PMID:26500441

  20. Identification of a plasmid-borne parathion hydrolase gene from Flavobacterium sp. by southern hybridization with opd from Pseudomonas diminuta.

    PubMed

    Mulbry, W W; Karns, J S; Kearney, P C; Nelson, J O; McDaniel, C S; Wild, J R

    1986-05-01

    Parathion hydrolases have been previously described for an American isolate of Pseudomonas diminuta and a Philippine isolate of Flavobacterium sp. (ATCC 27551). The gene which encodes the broad-spectrum organophosphate phosphotriesterase in P. diminuta has been shown by other investigators to be located on a 66-kilobase (kb) plasmid. The intact gene (opd, organophosphate-degrading gene) from this degradative plasmid was cloned into M13mp10 and found to express parathion hydrolase under control of the lac promoter in Escherichia coli. In Flavobacterium sp. strain ATCC 27551, a 43-kb plasmid was associated with the production of parathion hydrolase by curing experiments. The M13mp10-cloned fragment of the opd gene from P. diminuta was used to identify a homologous genetic region from Flavobacterium sp. strain ATCC 27551. Southern hybridization experiments demonstrated that a genetic region from the 43-kb Flavobacterium sp. plasmid possessed significant homology to the opd sequence. Similar hybridization did not occur with three other native Flavobacterium sp. plasmids (approximately 23, 27, and 51 kb) present within this strain or with genomic DNA from cured strains. Restriction mapping of various recombinant DNA molecules containing subcloned fragments of both opd plasmids revealed that the restriction maps of the two opd regions were similar, if not identical, for all restriction endonucleases tested thus far. In contrast, the restriction maps of the cloned plasmid sequences outside the opd regions were not similar. Thus, it appears that the two discrete bacterial plasmids from parathion-hydrolyzing soil bacteria possess a common but limited region of sequence homology within potentially nonhomologous plasmid structures.

  1. Identification of a plasmid-borne parathion hydrolase gene from Flavobacterium sp. by southern hybridization with opd from Pseudomonas diminuta.

    PubMed Central

    Mulbry, W W; Karns, J S; Kearney, P C; Nelson, J O; McDaniel, C S; Wild, J R

    1986-01-01

    Parathion hydrolases have been previously described for an American isolate of Pseudomonas diminuta and a Philippine isolate of Flavobacterium sp. (ATCC 27551). The gene which encodes the broad-spectrum organophosphate phosphotriesterase in P. diminuta has been shown by other investigators to be located on a 66-kilobase (kb) plasmid. The intact gene (opd, organophosphate-degrading gene) from this degradative plasmid was cloned into M13mp10 and found to express parathion hydrolase under control of the lac promoter in Escherichia coli. In Flavobacterium sp. strain ATCC 27551, a 43-kb plasmid was associated with the production of parathion hydrolase by curing experiments. The M13mp10-cloned fragment of the opd gene from P. diminuta was used to identify a homologous genetic region from Flavobacterium sp. strain ATCC 27551. Southern hybridization experiments demonstrated that a genetic region from the 43-kb Flavobacterium sp. plasmid possessed significant homology to the opd sequence. Similar hybridization did not occur with three other native Flavobacterium sp. plasmids (approximately 23, 27, and 51 kb) present within this strain or with genomic DNA from cured strains. Restriction mapping of various recombinant DNA molecules containing subcloned fragments of both opd plasmids revealed that the restriction maps of the two opd regions were similar, if not identical, for all restriction endonucleases tested thus far. In contrast, the restriction maps of the cloned plasmid sequences outside the opd regions were not similar. Thus, it appears that the two discrete bacterial plasmids from parathion-hydrolyzing soil bacteria possess a common but limited region of sequence homology within potentially nonhomologous plasmid structures. Images PMID:3015022

  2. Draft Genome Sequence of Pseudomonas sp. BDAL1 Reconstructed from a Bakken Shale Hydraulic Fracturing-Produced Water Storage Tank Metagenome

    PubMed Central

    Lipus, Daniel; Ross, Daniel

    2017-01-01

    ABSTRACT We report the 5,425,832 bp draft genome of Pseudomonas sp. strain BDAL1, recovered from a Bakken shale hydraulic fracturing-produced water tank metagenome. Genome annotation revealed several key biofilm formation genes and osmotic stress response mechanisms necessary for survival in hydraulic fracturing-produced water. PMID:28302780

  3. Decolorization of adsorbed textile dyes by developed consortium of Pseudomonas sp. SUK1 and Aspergillus ochraceus NCIM-1146 under solid state fermentation.

    PubMed

    Kadam, Avinash A; Telke, Amar A; Jagtap, Sujit S; Govindwar, Sanjay P

    2011-05-15

    The objective of this study was to develop consortium using Pseudomonas sp. SUK1 and Aspergillus ochraceus NCIM-1146 to decolorize adsorbed dyes from textile effluent wastewater under solid state fermentation. Among various agricultural wastes rice bran showed dye adsorption up to 90, 62 and 80% from textile dye reactive navy blue HE2R (RNB HE2R) solution, mixture of textile dyes and textile industry wastewater, respectively. Pseudomonas sp. SUK1 and A. ochraceus NCIM-1146 showed 62 and 38% decolorization of RNB HE2R adsorbed on rice bran in 24h under solid state fermentation. However, the consortium of Pseudomonas sp. SUK1 and A. ochraceus NCIM-1146 (consortium-PA) showed 80% decolorization in 24h. The consortium-PA showed effective ADMI removal ratio of adsorbed dyes from textile industry wastewater (77%), mixture of textile dyes (82%) and chemical precipitate of textile dye effluent (CPTDE) (86%). Secretion of extracellular enzymes such as laccase, azoreductase, tyrosinase and NADH-DCIP reductase and their significant induction in the presence of adsorbed dye suggests their role in the decolorization of RNB HE2R. GCMS and HPLC analysis of product suggests the different fates of biodegradation of RNB HE2R when used Pseudomonas sp. SUK1, A. ochraceus NCIM-1146 and consortium PA.

  4. Draft Genome Sequence of Pseudomonas sp. BDAL1 Reconstructed from a Bakken Shale Hydraulic Fracturing-Produced Water Storage Tank Metagenome.

    PubMed

    Lipus, Daniel; Ross, Daniel; Bibby, Kyle; Gulliver, Djuna

    2017-03-16

    We report the 5,425,832 bp draft genome of Pseudomonas sp. strain BDAL1, recovered from a Bakken shale hydraulic fracturing-produced water tank metagenome. Genome annotation revealed several key biofilm formation genes and osmotic stress response mechanisms necessary for survival in hydraulic fracturing-produced water.

  5. Role of phenazines and cyclic lipopeptides produced by pseudomonas sp. CMR12a in induced systemic resistance on rice and bean.

    PubMed

    Ma, Zongwang; Hua, Gia Khuong Hoang; Ongena, Marc; Höfte, Monica

    2016-08-25

    Pseudomonas sp. CMR12a produces two different classes of cyclic lipopeptides (CLPs) (orfamides and sessilins), which all play a role in direct antagonism against soilborne pathogens. Here we show that Pseudomonas sp. CMR12a is also able to induce systemic resistance to Magnaporthe oryzae on rice and to the web blight pathogen Rhizoctonia solani AG2-2 on bean. Plant assays with biosynthesis mutants of Pseudomonas sp. CMR12a impaired in the production of phenazines and/or CLPs and purified metabolites revealed that distinct bacterial determinants are responsible for inducing systemic resistance in these two pathosystems. In rice, mutants impaired in phenazine production completely lost their ability to induce systemic resistance, while a soil drench with pure phenazine-1-carboxamide (PCN) at a concentration of 0.1 or 1 μM was active in inducing resistance against M. oryzae. In bean, mutants that only produced phenazines, sessilins or orfamides were still able to induce systemic resistance against Rhizoctonia web blight, but a balanced production of these metabolites was needed. This study not only shows that Pseudomonas sp. CMR12a can protect rice to blast disease and bean to web blight disease, but also displays that the determinants involved in induced systemic resistance are plant, pathogen and concentration dependent.

  6. Biodegradation of biphenyl and removal of 2-chlorobiphenyl by Pseudomonas sp. KM-04 isolated from PCBs-contaminated mine impacted soil

    NASA Astrophysics Data System (ADS)

    Nam, I.; Chon, C.; Kim, J.; Kim, Y.

    2013-12-01

    The aim of the present study is to remediate the PCBs contaminated mine soil using microcosm study. For that, the naturally occurring microorganisms are stimulated and enriched in soil itself by supplementing biphenyl as well as benzoic acid. As a result the biphenyl degrading organisms are induced to degrade the PCBs contamination. From the stimulated soil, the biphenyl degrading organisms are isolated and degraded metabolites are elucidated. Pseudomonas sp. strain KM-04 was isolated from PCBs-contaminated soil in a coal mine-impacted area, and identification of bacteria was done by sequencing the 16S rRNA gene analysis. The growth of Pseudomonas sp. strain KM-04 using biphenyl as the sole carbon source was investigated by culturing in 100-mL Erlenmeyer flasks containing 10 ml sterilized MSM and 10 μg/ml biphenyl, and the ability of KM-04 to remove biphenyl and 2-chlorobiphenyl from mine soil was investigated. Metabolite formation was confirmed by liquid chromatography/atmospheric pressure chemical ionization-mass spectrometric analysis. Pseudomonas sp. strain KM-04 uses biphenyl as a sole carbon and energy source, and resting cells convert biphenyl to its metabolic intermediates, including dihydroxybiphenyl, 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoic acid, and benzoic acid. Incubation of real soil collected from abandoned mine areas with resting cells of Pseudomonas sp. strain KM-04 for 10 days resulted in the 98.5 % of biphenyl and 82.3 % of 2-chlorobiphenyl in a slurry system. The ability of the Pseudomonas sp. strain KM-04 to bioremediate biphenyl and 2-chlorobiphenyl from abandoned mine soil was examined using soil microcosm studies under laboratory conditions. Treatment of mine soil with the Pseudomonas sp. strain KM-04 for 15 days resulted in 87.1 % reduction in biphenyl and 68.7 % in 2-chlorobiphenyl contents. The results suggest that Pseudomonas sp. strain KM-04 is a potential candidate for the biological removal of biphenyl and chlorinated derivatives

  7. Degradation of phenol and m-toluate in Pseudomonas sp. strain EST1001 and its Pseudomonas putida transconjugants is determined by a multiplasmid system.

    PubMed Central

    Kivisaar, M A; Habicht, J K; Heinaru, A L

    1989-01-01

    The utilization of phenol, m-toluate, and salicylate (Phe+, mTol+, and Sal+ characters, respectively) in Pseudomonas sp. strain EST1001 is determined by the coordinated expression of genes placed in different plasmids, i.e., by a multiplasmid system. The natural multiplasmid strain EST1001 is phenotypically unstable. In its Phe-, mTol-, and Sal- segregants, the plasmid DNA underwent structural rearrangements without a marked loss of plasmid DNA, and the majority of segregants gave revertants. The genes specifying the degradation of phenol and m-toluate were transferable to P. putida PaW340, and in this strain a new multiplasmid system with definite structural changes was formed. The 17-kilobase transposable element, a part of the TOL plasmid pWWO present in the chromosome of PaW340, was inserted into the plasmid DNA in transconjugants. In addition, transconjugant EST1020 shared pWWO-like structures. Enzyme assays demonstrated that ortho-fission reactions were used by bacteria that grew on phenol, whereas m-toluate was catabolized by a meta-fission reaction. Salicylate was a functional inducer of the enzymes of both pathways. The expression of silent metabolic pathways of phenol or m-toluate degradation has been observed in EST1001 Phe- mTol+ and Phe+ mTol- transconjugants. The switchover of phenol degradation from the ortho- to the meta-pathway in EST1033 also showed the flexibility of genetic material in EST1001 transconjugants. Images PMID:2768199

  8. Further characterization of o-nitrobenzaldehyde degrading bacterium Pseudomonas sp. ONBA-17 and deduction on its metabolic pathway.

    PubMed

    Yu, Fang-Bo; Li, Xiao-Dan; Ali, Shinawar Waseem; Shan, Sheng-Dao; Luo, Lin-Ping; Guan, Li-Bo

    2014-01-01

    A previously reported o-nitrobenzaldehyde (ONBA) degrading bacterium Pseudomonas sp. ONBA-17 was further identified and characterized. Based on results of DNA base composition and DNA-DNA hybridization, the strain was identified as P. putida. Its degradation effect enhanced with increase of inoculum amount and no lag phase was observed. Higher removal rate was achieved under shaking conditions. All tested ONBA with different initial concentrations could be completely degraded within 5 d. In addition, degradative enzyme(s) involved was confirmed as intra-cellular distributed and constitutively expressed. Effects of different compounds on relative activity of degradative enzyme(s) within cell-free extract were also evaluated. Finally, 2-nitrobenzoic acid and 2, 3-dihydroxybenzoic acid were detected as metabolites of ONBA degradation by P. putida ONBA-17, and relevant metabolic pathway was preliminary proposed. This study might help with future research in better understanding of nitroaromatics biodegradation.

  9. Differentiating Pseudomonas sp. strain ADP cells in suspensions and biofilms using Raman spectroscopy and scanning electron microscopy.

    PubMed

    Henry, Victoria A; Jessop, Julie L P; Peeples, Tonya L

    2017-02-01

    High quality spectra of Pseudomonas sp. strain ADP in the planktonic and biofilm state were obtained using Raman microspectroscopy. These spectra enabled the identification of key differences between free and biofilm cells in the fingerprint region of Raman spectra in the nucleic acid, carbohydrate, and protein regions. Scanning electron microscopy (SEM) enabled detailed visualization of ADP biofilm with confirmation of associated extracellular matrix structure. Following extraction and Raman analysis of extracellular polymeric substances, Raman spectral differences between free and biofilm cells were largely attributed to the contribution of extracellular matrix components produced in mature biofilms. Raman spectroscopy complemented with SEM proves to be useful in distinguishing physiological properties among cells of the same species. Graphical Abstract Raman spectroscopy complemented with SEM proves to be useful in distinguishing physiological properties among cells of the same species.

  10. Isolation of a malachite green-degrading Pseudomonas sp. MDB-1 strain and cloning of the tmr2 gene.

    PubMed

    Li, Lian-tai; Hong, Qing; Yan, Xin; Fang, Gui-hua; Ali, Shinawar Waseem; Li, Shun-peng

    2009-11-01

    The release of malachite green, a commonly used triphenylmethane dye, into the environment is causing increasing concern due to its toxicity, mutagenicity, and carcinogenicity. A bacterial strain that could degrade malachite green was isolated from the water of an aquatic hatchery. It was identified as a Pseudomonas sp. based on the morphological, physiological, and biochemical characteristics, as well as the analysis of 16S rRNA gene sequence and designated as MDB-1. This strain was capable of degrading both malachite green and leucomalachite green, as well as other triphenylmethane dyes including Crystal Violet and Basic Fuchsin. The gene tmr2, encoding the triphenylmethane reductase from MDB-1, was cloned, sequenced and effectively expressed in E. coli. These results highlight the potential of this bacterium for the bioremediation of aquatic environments contaminated by malachite green.

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

    SciTech Connect

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

    2006-07-15

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

  12. Oxidative release of nitrite from 2-nitrotoluene by a three-component enzyme system from Pseudomonas sp. strain JS42.

    PubMed

    An, D; Gibson, D T; Spain, J C

    1994-12-01

    Pseudomonas sp. strain JS42 utilizes 2-nitrotoluene (2NT) as the sole source of carbon and energy for growth. Intact cells catalyze the oxidation of 2NT to 3-methylcatechol and nitrite in a reaction that requires molecular oxygen. Cell extracts oxidized 2NT to 3-methylcatechol and nitrite in the presence of NAD(P)H and ferrous iron. Ion-exchange chromatography yielded three protein fractions (A, B, and C) which were all required for the oxidation of 2NT to 3-methylcatechol and nitrite. Component B (reductase2NT) catalyzed a NAD(P)H-dependent reduction of cytochrome c. Solutions of component A (ISP2NT) were brown and showed absorption maxima at 458 and 324 nm. Two major bands with M(r)s 52,500 and 28,000 were observed when ISP2NT was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Component C could be replaced by ferredoxin NAP from the Pseudomonas putida NCIB 9816-4 naphthalene dioxygenase system and was given the designation ferredoxin2NT. Experiments with 18O2 showed that both oxygen atoms were added to the aromatic ring of 2NT to yield 3-methylcatechol. The enzyme is a new multicomponent enzyme system which we have designated 2NT 2,3-dioxygenase.

  13. Oxidative release of nitrite from 2-nitrotoluene by a three-component enzyme system from Pseudomonas sp. strain JS42.

    PubMed Central

    An, D; Gibson, D T; Spain, J C

    1994-01-01

    Pseudomonas sp. strain JS42 utilizes 2-nitrotoluene (2NT) as the sole source of carbon and energy for growth. Intact cells catalyze the oxidation of 2NT to 3-methylcatechol and nitrite in a reaction that requires molecular oxygen. Cell extracts oxidized 2NT to 3-methylcatechol and nitrite in the presence of NAD(P)H and ferrous iron. Ion-exchange chromatography yielded three protein fractions (A, B, and C) which were all required for the oxidation of 2NT to 3-methylcatechol and nitrite. Component B (reductase2NT) catalyzed a NAD(P)H-dependent reduction of cytochrome c. Solutions of component A (ISP2NT) were brown and showed absorption maxima at 458 and 324 nm. Two major bands with M(r)s 52,500 and 28,000 were observed when ISP2NT was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Component C could be replaced by ferredoxin NAP from the Pseudomonas putida NCIB 9816-4 naphthalene dioxygenase system and was given the designation ferredoxin2NT. Experiments with 18O2 showed that both oxygen atoms were added to the aromatic ring of 2NT to yield 3-methylcatechol. The enzyme is a new multicomponent enzyme system which we have designated 2NT 2,3-dioxygenase. Images PMID:8002568

  14. Increased concentration of Pseudomonas aeruginosa and Staphylococcus sp. in small animals exposed to aerospace environments

    NASA Technical Reports Server (NTRS)

    Guthrie, R. K.

    1976-01-01

    The effects of increased concentrations of PSEUDOMONAS AERUGINOSA AND STAPHYLOCOCCUS in the total bacterial flora of small animals exposed to simulated spacecraft environments were evaluated. Tests to detect changes in infectivity, effects of antibiotic treatments, immune responses to bacterial antigens, and effectiveness of immune responses in the experimental environment were conducted. The most significant results appear to be the differences in immune responses at simulated altitudes and the production of infection in the presence of a specific antibody.

  15. Complete Nucleotide Sequence and Organization of the Atrazine Catabolic Plasmid pADP-1 from Pseudomonas sp. Strain ADP

    PubMed Central

    Martinez, Betsy; Tomkins, Jeffrey; Wackett, Lawrence P.; Wing, Rod; Sadowsky, Michael J.

    2001-01-01

    The complete 108,845-nucleotide sequence of catabolic plasmid pADP-1 from Pseudomonas sp. strain ADP was determined. Plasmid pADP-1 was previously shown to encode AtzA, AtzB, and AtzC, which catalyze the sequential hydrolytic removal of s-triazine ring substituents from the herbicide atrazine to yield cyanuric acid. Computational analyses indicated that pADP-1 encodes 104 putative open reading frames (ORFs), which are predicted to function in catabolism, transposition, and plasmid maintenance, transfer, and replication. Regions encoding transfer and replication functions of pADP-1 had 80 to 100% amino acid sequence identity to pR751, an IncPβ plasmid previously isolated from Enterobacter aerogenes. pADP-1 was shown to contain a functional mercury resistance operon with 99% identity to Tn5053. Complete copies of transposases with 99% amino acid sequence identity to TnpA from IS1071 and TnpA from Pseudomonas pseudoalcaligenes were identified and flank each of the atzA, atzB, and atzC genes, forming structures resembling nested catabolic transposons. Functional analyses identified three new catabolic genes, atzD, atzE, and atzF, which participate in atrazine catabolism. Crude extracts from Escherichia coli expressing AtzD hydrolyzed cyanuric acid to biuret. AtzD showed 58% amino acid sequence identity to TrzD, a cyanuric acid amidohydrolase, from Pseudomonas sp. strain NRRLB-12227. Two other genes encoding the further catabolism of cyanuric acid, atzE and atzF, reside in a contiguous cluster adjacent to a potential LysR-type transcriptional regulator. E. coli strains bearing atzE and atzF were shown to encode a biuret hydrolase and allophanate hydrolase, respectively. atzDEF are cotranscribed. AtzE and AtzF are members of a common amidase protein family. These data reveal the complete structure of a catabolic plasmid and show that the atrazine catabolic genes are dispersed on three disparate regions of the plasmid. These results begin to provide insight into how

  16. Plasmid-borne catabolism of methyl parathion and p-nitrophenol in Pseudomonas sp. strain WBC-3.

    PubMed

    Liu, Hong; Zhang, Jun-Jie; Wang, Su-Jun; Zhang, Xian-En; Zhou, Ning-Yi

    2005-09-09

    Pseudomonas sp. strain WBC-3 utilises methyl parathion (MP) or p-nitrophenol (PNP) as the sole source of carbon, nitrogen, and energy. A plasmid designated pZWL0 of approximately 70 kb in this strain was found to be responsible for MP and PNP degradation. This was based on the fact that the plasmid-cured strains showed PNP- MP- phenotype and the PNP+ MP+ phenotype could be conjugally transferred. We have also cloned a 3.4-kb HindIII fragment which exhibited methyl parathion hydrolase activity, which revealed a methyl parathion hydrolase (mph) gene whose DNA sequence is 99.5% identical to the recently identified mpd gene from Plesiomonas sp. M6 [C. Zhongli, L. Shunpeng, F. Guoping, Isolation of methyl parathion-degrading strain M6 and cloning of the methyl parathion hydrolase gene, Appl. Environ. Microbiol. 67 (2001) 4922-4925]. The mph gene was functionally expressed in Escherichia coli and the relative activities of the enzyme against different substrates were determined. The sequence alignment and phylogenetic analysis suggested that MPH and MPD evolved independently from other well-studied organophosphate hydrolases and may be originated from class B beta-lactamase family. Subsequently obtained a 6.5-kb KpnI and BamHI fragment containing the above HindIII fragment revealed that the mph gene was physically located in a typical transposon.

  17. Microbial degradation of pyridine using Pseudomonas sp. and isolation of plasmid responsible for degradation.

    PubMed

    Mohan, S Venkata; Sistla, Srinivas; Guru, R Kumar; Prasad, K Krishna; Kumar, C Suresh; Ramakrishna, S V; Sarma, P N

    2003-01-01

    Pseudomonas (PI2) capable of degrading pyridine was isolated from the mixed population of the activated sludge unit which was being used for treating complex effluents, the strain was characterized. Aerobic degradation of pyridine was studied with the isolated strain and the growth parameters were evaluated. Pyridine degradation was further conformed by chromatography (HPLC) analysis. The process parameters like biomass growth and dissolved oxygen consumption were monitored during pyridine degradation. In order to conform with the plasmid capability to degrade pyridine, the requisite plasmid was isolated and transferred to DH 5alpha Escherichia coli. The subsequent biodegradation studies revealed the ability of the transformed plasmid capability to degrade the pyridine.

  18. Oily wastewaters treatment using Pseudomonas sp. isolated from the compost fertilizer

    PubMed Central

    2014-01-01

    Background Discharging the oily wastewater in the environment causes serious problems, because of the oil compounds and organic materials presence. Applying biological methods using the lipase enzyme producer microorganisms can be an appropriate choice for treatment of these wastewaters. The aim of this study is to treat those oil wastewaters having high concentration of oil by applying lipase enzyme producer bacteria. Materials and methods Oil concentration measurement was conducted using the standard method of gravimetric and the wastewater under study was synthetically made and contained olive, canola and sunflower oil. The strain used in this study was Pseudomonas strain isolated from compost fertilizer. The oil under study had concentration of 1.5 to 22 g/l. Results The oil removal amount in concentrations lower than 8.4 g/l was over 95 ± 1.5%. Increase of the oil's concentration to 22 g/l decreases the amount of removal in retention time of 44 hours to 85 ± 2.5%. The best yield of removing this strain in retention time of 44 hours and temperature of 30°C was achieved using Ammonium Nitrate as the nitrogen resource which yield was about 95 percent. Conclusion The findings of the research showed that Pseudomonas bacteria isolated from the compost fertilizer can degrade high concentration oils. PMID:24876932

  19. Maintenance and induction of naphthalene degradation activity in Pseudomonas putida and an Alcaligenes sp. under different culture conditions.

    PubMed

    Guerin, W F; Boyd, S A

    1995-11-01

    The expression of xenobiotic-degradative genes in indigenous bacteria or in bacteria introduced into an ecosystem is essential for the successful bioremediation of contaminated environments. The maintenance of naphthalene utilization activity is studied in Pseudomonas putida (ATCC 17484) and an Alcaligenes sp. (strain NP-Alk) under different batch culture conditions. Levels of activity decreased exponentially in stationary phase with half-lives of 43 and 13 h for strains ATCC 17484 and NP-Alk, respectively. Activity half-lives were 2.7 and 5.3 times longer, respectively, in starved cultures than in stationary-phase cultures following growth on naphthalene. The treatment of starved cultures with chloramphenicol caused a loss of activity more rapid than that measured in untreated starved cultures, suggesting a continued enzyme synthesis in starved cultures in the absence of a substrate. Following growth in nutrient medium, activity decreased to undetectable levels in the Alcaligenes sp. but remained at measurable levels in the pseudomonad even after 9 months. The induction of naphthalene degradation activities in these cultures, when followed by radiorespirometry with 14C-labeled naphthalene as the substrate, was consistent with activity maintenance data. In the pseudomonad, naphthalene degradation activity was present constitutively at low levels under all growth conditions and was rapidly (in approximately 15 min) induced to high levels upon exposure to naphthalene. Adaptation in the uninduced Alcaligenes sp. occurred after many hours of exposure to naphthalene. In vivo labeling with 35S, to monitor the extent of de novo enzyme synthesis by naphthalene-challenged cells, provided an independent confirmation of the results.

  20. Maintenance and induction of naphthalene degradation activity in Pseudomonas putida and an Alcaligenes sp. under different culture conditions

    SciTech Connect

    Guerin, W.F.; Boyd, S.A.

    1995-11-01

    The expression of xenobiotic-degradative genes in indigenous bacteria or in bacteria introduced into an ecosystem is essential for the successful bioremediation of contaminated environments. The maintenance of naphthalene utilization activity is studied in Pseudomonas putida (ATCC 17484) and an Alcaligenes sp. (strain NP-Alk) under different batch culture conditions. Levels of activity decreased exponentially in stationary phase with half-lives of 43 and 13 h for strains ATCC 17484 nad NP-Alk, respectively. Activity half-lives were 2.7 and 5.3 times longer, respectively, in starved cultures than in stationary-phase cultures following growth on naphthalene. The treatment of starved cultures with chloramphenicol caused a loss of activity more rapid than that measured in untreated starved cultures, suggesting a continued enzyme synthesis in starved cultures in the absence of a substrate. Following growth in nutrient medium, activity decreased to undetectable levels in the Alcaligenes sp. but remained at measureable levels int he pseudomonad even after 9 months. The induction of naphthalene degradation activities in these cultures, when followed by radiorespirometry with {sup 14}C-labeled naphthalene as the substrate, was consistent with activity maintenance data. In the pseudomonad, naphthalene degradation activity was present constitutively at low levels under all growth conditions and was rapidly (in approximately 15 min) induced to high levels upon exposure to naphthalene. Adaptation in the uninduced Alcaligenes sp. occurred after many hours of exposure to naphthalene. In vivo labeling with {sup 35}S, to monitor the extent of de novo enzyme synthesis by naphthalene-challenged cells, provided an independent confirmation of the results. 43 refs., 9 figs., 1 tab.

  1. Pseudomonas aeruginosa and Achromobacter sp. Clonal Selection Leads to Successive Waves of Contamination of Water in Dental Care Units

    PubMed Central

    Abdouchakour, Fatima; Dupont, Chloé; Grau, Delphine; Aujoulat, Fabien; Mournetas, Patricia; Marchandin, Hélène; Parer, Sylvie; Gibert, Philippe; Valcarcel, Jean

    2015-01-01

    Dental care unit waterlines (DCUWs) consist of complex networks of thin tubes that facilitate the formation of microbial biofilms. Due to the predilection toward a wet environment, strong adhesion, biofilm formation, and resistance to biocides, Pseudomonas aeruginosa, a major human opportunistic pathogen, is adapted to DCUW colonization. Other nonfermentative Gram-negative bacilli, such as members of the genus Achromobacter, are emerging pathogens found in water networks. We reported the 6.5-year dynamics of bacterial contamination of waterlines in a dental health care center with 61 dental care units (DCUs) connected to the same water supply system. The conditions allowed the selection and the emergence of clones of Achromobacter sp. and P. aeruginosa characterized by multilocus sequence typing, multiplex repetitive elements-based PCR, and restriction fragment length polymorphism in pulsed-field gel electrophoresis, biofilm formation, and antimicrobial susceptibility. One clone of P. aeruginosa and 2 clones of Achromobacter sp. colonized successively all of the DCUWs: the last colonization by P. aeruginosa ST309 led to the closing of the dental care center. Successive dominance of species and clones was linked to biocide treatments. Achromobacter strains were weak biofilm producers compared to P. aeruginosa ST309, but the coculture of P. aeruginosa and Achromobacter enhanced P. aeruginosa ST309 biofilm formation. Intraclonal genomic microevolution was observed in the isolates of P. aeruginosa ST309 collected chronologically and in Achromobacter sp. clone A. The contamination control was achieved by a complete reorganization of the dental health care center by removing the connecting tubes between DCUs. PMID:26296724

  2. The role of wheat germ agglutinin in the attachment of Pseudomonas sp. WS32 to wheat root.

    PubMed

    Zhang, Jian; Meng, Liyuan; Cao, Yuanyuan; Chang, Huiping; Ma, Zhongyou; Sun, Leni; Zhang, Ming; Tang, Xinyun

    2014-12-01

    Wheat germ agglutinin (WGA), which is secreted on the surface of wheat root, has been defined as a protein that reversibly and non-enzymatically binds to specific carbohydrates. However, little attention has been paid to the function of WGA in the attachment of bacteria to their host plants. The aim of this study was to investigate the role of WGA in the attachment of Pseudomonas sp. WS32 to wheat roots. Wheat roots were initially treated with double-distilled water, WGA-H (WGA solution that was heated at 100°C for 15 min) and WGA, independently. Subsequently, the roots were co-incubated with cell solutions (10⁹ cells/ml). A dilution plate method using a solid nutrient medium was employed to determine the adsorption of WS32 to wheat roots. WGA was labeled with fluorescein isothiocyanate and detected using the fluorescent in situ hybridization (FISH) technique. The number of adsorptive WS32 cells on wheat roots was significantly increased when the wheat roots were pretreated with WGA, compared with the control treatment (p = 0.01). However, WGA-H failed to increase the amount of bacterial cells that attached to the wheat roots because of the loss of its physiological activity. The FISH assay also revealed that more cells adhered to WGA-treated wheat roots than to control or WGA-H-treated roots. The results indicated that WGA can mediate Pseudomonas strain WS32's adherence to wheat seedling roots. The findings of this study provide a better understanding of the processes involved in plant-microbe interactions.

  3. Extracellular lipase of Pseudomonas sp. strain ATCC 21808: purification, characterization, crystallization, and preliminary X-ray diffraction data.

    PubMed Central

    Kordel, M; Hofmann, B; Schomburg, D; Schmid, R D

    1991-01-01

    A procedure for the purification of a very hydrophobic lipase from Pseudomonas sp. strain ATCC 21808 was elaborated by avoiding the use of long-chain detergents in view of subsequent crystallization of the enzyme. The purification procedure included chromatography on Q-Sepharose in the presence of n-octyl-beta-D-glucopyranoside, Ca2+ precipitation of fatty acids, and Octyl-Sepharose chromatography. The enzyme was purified 260-fold to a yield of 35% and a specific activity of 3,300 U/mg. The molecular weight was determined as 35,000; a polyacrylamide gel under nondenaturing conditions revealed a band at 110,000, and the isoelectric point proved to be at 4.5 to 4.6. The lipase crystallized with different salts and ethylene glycol polymers in the presence of n-octyl-beta-D-glucopyranoside and one alkyloligooxyethylene compound (CxEy) in the range from C5E2 to C8E4. The crystals diffract to a resolution of about 0.25 nm. Precession photographs revealed that they belong to space group C2 with lattice constants of a = 9.27 nm, b = 4.74 nm, c = 8.65 nm, and beta = 122.3 degrees, indicating a cell content of one molecule per asymmetric unit of the crystal. In hydrolysis of triglycerides, the lipase showed substrate specificity for saturated fatty acids from C6 to C12 and unsaturated long-chain fatty acids. Monoglycerides were hydrolyzed very slowly. The N-terminal sequence is identical to that of the lipase from Pseudomonas cepacia. Treatment with diethyl-p-nitrophenylphosphate affected the activities toward triolein and p-nitrophenylacetate to the same extent and with the same velocity. Images PMID:1856176

  4. Real-Time Solvent Tolerance Analysis of Pseudomonas sp. Strain VLB120ΔC Catalytic Biofilms▿ †

    PubMed Central

    Halan, Babu; Schmid, Andreas; Buehler, Katja

    2011-01-01

    Biofilms are ubiquitous surface-associated microbial communities embedded in an extracellular polymeric (EPS) matrix, which gives the biofilm structural integrity and strength. It is often reported that biofilm-grown cells exhibit enhanced tolerance toward adverse environmental stress conditions, and thus there has been a growing interest in recent years to use biofilms for biotechnological applications. We present a time- and locus-resolved, noninvasive, quantitative approach to study biofilm development and its response to the toxic solvent styrene. Pseudomonas sp. strain VLB120ΔC-BT-gfp1 was grown in modified flow-cell reactors and exposed to the solvent styrene. Biofilm-grown cells displayed stable catalytic activity, producing (S)-styrene oxide continuously during the experimental period. The pillar-like structure and growth rate of the biofilm was not influenced by the presence of the solvent. However, the cells experience severe membrane damage during styrene treatment, although they obviously are able to adapt to the solvent, as the amount of permeabilized cells decreased from 75 to 80% down to 40% in 48 h. Concomitantly, the fraction of concanavalin A (ConA)-stainable EPS increased, substantiating the assumption that those polysaccharides play a major role in structural integrity and enhanced biofilm tolerance toward toxic environments. Compared to control experiments with planktonic grown cells, the Pseudomonas biofilm adapted much better to toxic concentrations of styrene, as nearly 65% of biofilm cells were not permeabilized (viable), compared to only 7% in analogous planktonic cultures. These findings underline the robustness of biofilms under stress conditions and its potential for fine chemical syntheses. PMID:21193676

  5. Biocontrol Potential of Siderophore Producing Heavy Metal Resistant Alcaligenes sp. and Pseudomonas aeruginosa RZS3 vis-à-vis Organophosphorus Fungicide.

    PubMed

    Sayyed, R Z; Patel, P R

    2011-07-01

    In present study in vitro phytopathogen suppression activity of siderophoregenic preparations of Ni and Mn resistant Alcaligenes sp. STC1 and Pseudomonas aeruginosa RZS3 SH-94B isolated from soil were found superior over the chemical pesticide. Siderophore rich culture broth and siderophore rich supernatant exerted antifungal activity against Aspergillus niger NCIM 1025, Aspergillus flavus NCIM 650, Fusarium oxysporum NCIM 1281, Alternaria alternata ARI 715, Cercospora arachichola, Metarhizium anisopliae NCIM 1311 and Pseudomonas solanacerum NCIM 5103. Siderophore rich broth and supernatant exhibited potent antifungal activity vis-à-vis oraganophosphorus chemical fungicide; kitazine. The minimum fungicidal concentration required was 25 μl for Aspergillus niger, Aspergillus flavus, Fusarium oxysporum, Cercospora arachichola, Metarhizium anisopliae, Pseudomonas solanacerum and 75 μl for A. alternata.

  6. Cloning and Characterisation of (R)-3-hydroxyacyl-acyl Carrier Protein-coenzyme A Transferase Gene (phaG) from Pseudomonas sp. USM 4-55.

    PubMed

    Arsad, Hasni; Sudesh, Kumar; Nazalan, Najimudin; Muhammad, Tengku Sifzizul Tengku; Wahab, Habibah; Razip Samian, Mohd

    2009-12-01

    The (R)-3-hydroxyacyl-ACP-CoA transferase catalyses the conversion of (R)-3-hydroxyacyl-ACP to (R)-3-hydroxyacyl-CoA derivatives, which serves as the ultimate precursor for polyhydroxyalkanoate (PHA) polymerisation from unrelated substrates in pseudomonads. PhaG was found to be responsible for channelling precursors for polyhydroxyalkanoate (PHA) synthase from a de novo fatty acid biosynthesis pathway when cultured on carbohydrates, such as glucose or gluconate. The phaG gene was cloned from Pseudomonas sp. USM 4-55 using a homologous probe. The gene was located in a 3660 bp Sal I fragment (GenBank accession number EU305558). The open reading frame (ORF) was 885 bp long and encoded a 295 amino acid protein. The predicted molecular weight was 33251 Da, and it showed a 62% identity to the PhaG of Pseudomonas aeruginosa. The function of the cloned phaG of Pseudomonas sp. USM 4-55 was confirmed by complementation studies. Plasmid pBCS39, which harboured the 3660 bp Sal I fragment, was found to complement the PhaG-mutant heterologous host cell, Pseudomonas putida PhaGN-21. P. putida PhaGN-21, which harboured pBCS39, accumulated PHA that accounted for up to 18% of its cellular dry weight (CDW). P. putida PhaGN-21, which harboured the vector alone (PBBR1MCS-2), accumulated only 0.6% CDW of PHA.

  7. Draft Genome Sequence of Pseudomonas sp. Strain BMS12, a Plant Growth-Promoting and Protease-Producing Bacterium, Isolated from the Rhizosphere Sediment of Phragmites karka of Chilika Lake, India.

    PubMed

    Mishra, Samir R; Panda, Ananta Narayan; Ray, Lopamudra; Sahu, Neha; Mishra, Gayatri; Jadhao, Sudhir; Suar, Mrutyunjay; Adhya, Tapan Kumar; Rastogi, Gurdeep; Pattnaik, Ajit Kumar; Raina, Vishakha

    2016-06-30

    We report the 4.51 Mb draft genome of Pseudomonas sp. strain BMS12, a Gram-negative bacterium in the class of Gammaproteobacteria, isolated from the rhizospheric sediment of Phragmites karka, an invasive weed in Chilika Lake, Odisha, India. The Pseudomonas sp. strain BMS12 is capable of producing proteases and is also an efficient plant growth promoter that can be useful for various phytoremedial and industrial applications.

  8. Use of silica-encapsulated Pseudomonas sp. strain NCIB 9816-4 in biodegradation of novel hydrocarbon ring structures found in hydraulic fracturing waters.

    PubMed

    Aukema, Kelly G; Kasinkas, Lisa; Aksan, Alptekin; Wackett, Lawrence P

    2014-08-01

    The most problematic hydrocarbons in hydraulic fracturing (fracking) wastewaters consist of fused, isolated, bridged, and spiro ring systems, and ring systems have been poorly studied with respect to biodegradation, prompting the testing here of six major ring structural subclasses using a well-characterized bacterium and a silica encapsulation system previously shown to enhance biodegradation. The direct biological oxygenation of spiro ring compounds was demonstrated here. These and other hydrocarbon ring compounds have previously been shown to be present in flow-back waters and waters produced from hydraulic fracturing operations. Pseudomonas sp. strain NCIB 9816-4, containing naphthalene dioxygenase, was selected for its broad substrate specificity, and it was demonstrated here to oxidize fundamental ring structures that are common in shale-derived waters but not previously investigated with this or related enzymes. Pseudomonas sp. NCIB 9816-4 was tested here in the presence of a silica encasement, a protocol that has previously been shown to protect bacteria against the extremes of salinity present in fracking wastewaters. These studies demonstrate the degradation of highly hydrophobic compounds by a silica-encapsulated model bacterium, demonstrate what it may not degrade, and contribute to knowledge of the full range of hydrocarbon ring compounds that can be oxidized using Pseudomonas sp. NCIB 9816-4.

  9. Use of Silica-Encapsulated Pseudomonas sp. Strain NCIB 9816-4 in Biodegradation of Novel Hydrocarbon Ring Structures Found in Hydraulic Fracturing Waters

    PubMed Central

    Aukema, Kelly G.; Kasinkas, Lisa; Aksan, Alptekin

    2014-01-01

    The most problematic hydrocarbons in hydraulic fracturing (fracking) wastewaters consist of fused, isolated, bridged, and spiro ring systems, and ring systems have been poorly studied with respect to biodegradation, prompting the testing here of six major ring structural subclasses using a well-characterized bacterium and a silica encapsulation system previously shown to enhance biodegradation. The direct biological oxygenation of spiro ring compounds was demonstrated here. These and other hydrocarbon ring compounds have previously been shown to be present in flow-back waters and waters produced from hydraulic fracturing operations. Pseudomonas sp. strain NCIB 9816-4, containing naphthalene dioxygenase, was selected for its broad substrate specificity, and it was demonstrated here to oxidize fundamental ring structures that are common in shale-derived waters but not previously investigated with this or related enzymes. Pseudomonas sp. NCIB 9816-4 was tested here in the presence of a silica encasement, a protocol that has previously been shown to protect bacteria against the extremes of salinity present in fracking wastewaters. These studies demonstrate the degradation of highly hydrophobic compounds by a silica-encapsulated model bacterium, demonstrate what it may not degrade, and contribute to knowledge of the full range of hydrocarbon ring compounds that can be oxidized using Pseudomonas sp. NCIB 9816-4. PMID:24907321

  10. Uranium and thorium sequestration by a Pseudomonas sp.: mechanism and chemical characterization.

    PubMed

    Kazy, Sufia K; D'Souza, S F; Sar, Pinaki

    2009-04-15

    The mechanism and chemical nature of uranium and thorium sequestration by a Pseudomonas strain was investigated by transmission electron microscopy, energy dispersive X-ray (EDX) analysis, FTIR spectroscopy and X-ray diffractometry. Atomic force microscopy (AFM) used in the tapping mode elucidated the morphological changes in bacterial cells following uranium and thorium binding. Transmission electron microscopy revealed intracellular sequestration of uranium and thorium throughout the cell cytoplasm with electron dense microprecipitations of accumulated metals. Energy dispersive X-ray analysis confirmed the cellular deposition of uranium and thorium. EDX and elemental analysis of sorption solution indicated the binding of uranium and thorium by the bacterial biomass via displacement of cellular potassium and calcium. The strong involvement of cellular phosphate, carboxyl and amide groups in radionuclide binding was ascertained by FTIR spectroscopy. X-ray powder diffraction (XRD) analyses confirmed cellular sequestration of crystalline uranium and thorium phosphates. Overall results indicate that a combined ion-exchange-complexation-microprecipitation mechanism could be involved in uranium and thorium sequestration by this bacterium. Atomic force microscopy and topography analysis revealed an undamaged cell surface with an increase in cell length, width and height following radionuclide accumulation. The arithmetic average roughness (R(a)) and root mean square (RMS) roughness (R(q)) values indicated an increase in surface roughness following uranium and thorium sequestration.

  11. Growth of Pseudomonas sp. TX1 on a wide range of octylphenol polyethoxylate concentrations and the formation of dicarboxylated metabolites.

    PubMed

    Lin, Yi-Wen; Guo, Gia-Luen; Hsieh, Hsiao-Cheng; Huang, Shir-Ly

    2010-04-01

    Pseudomonas sp. TX1, is able to use octylphenol polyethoxylates (OPEO(n), or Triton X-100; average n = 9.5) as a sole carbon source. It can grow on 0.05-20% of OPEO(n) with a specific growth rate of 0.34-0.44 h(-1). High-performance liquid chromatography-mass spectrometer analysis of OPEO(n) degraded metabolites revealed that strain TX1 was able to shorten the ethoxylate chain and produce octylphenol (OP). Furthermore, formation of the short carboxylate metabolites, such as carboxyoctylphenol polyethoxylates (COPEO(n), n = 2, 3) and carboxyoctylphenol polyethoxycarboxylates (COPEC(n), n = 2, 3) began at the log stage, while octylphenol polyethoxycarboxylates (OPEC(n), n = 1-3) was formed at the stationary phase. All the short-ethoxylated metabolites, OPEO(n), OPEC(n), COPEO(n), and COPEC(n), accumulated when the cells were in the stationary phase. This study is the first to demonstrate the formation of COPEO(n) and COPEC(n) from OPEO(n) by an aerobic bacterium.

  12. Anaerobic biodegradation of high-molecular-weight polycyclic aromatic hydrocarbons by a facultative anaerobe Pseudomonas sp. JP1.

    PubMed

    Liang, Lei; Song, Xiaohui; Kong, Jing; Shen, Chenghui; Huang, Tongwang; Hu, Zhong

    2014-11-01

    Polycyclic aromatic hydrocarbons (PAHs) are harmful persistent organic pollutants, while the high-molecular-weight (HMW) PAHs are even more detrimental to the environment and human health. However, microbial anaerobic degradation of HMW PAHs has rarely been reported. One facultative anaerobe Pseudomonas sp. JP1 was isolated from Shantou Bay, Shantou, China, which could degrade a variety of HMW PAHs. After 40 days cultivation with strain JP1, anaerobic biodegradation rate of benzo[a]pyrene (BaP), fluoranthene, and phenanthrene was 30, 47, and 5 %, respectively. Consumption of nitrate as the electron acceptor was confirmed by N-(1-naphthyl) ethylenediamine spectrophotometry. Supplementation of sodium sulfite, maltose, or glycine, and in a salinity of 0-20 ‰ significantly stimulated anaerobic degradation of BaP. Lastly, the anaerobic degradation metabolites of BaP by strain JP1 were investigated using GC/MS, and the degradation pathway was proposed. This study is helpful for further studies on the mechanism of anaerobic biodegradation of PAHs.

  13. Medium factor optimization and fermentation kinetics for phenazine-1-carboxylic acid production by Pseudomonas sp. M18G.

    PubMed

    He, Li; Xu, Yu-Quan; Zhang, Xue-Hong

    2008-06-01

    We investigated the production of biofungicide phenazine-1-carboxlic (PCA) by Pseudomonas sp. M18G, a gacA-deficient mutant of M18 for PCA high-production. Glucose was chosen as the optimal carbon source and soy peptone as the nitrogen source. A Plackett-Burman design revealed that glucose, soy peptone and NaCl were the most significant factors in PCA fermentation. Response surface methodology (RSM) and artificial neural network (ANN) models involving the significant factors were developed using common data. The prediction accuracy of ANN was slightly higher compared to RSM. The genetic algorithm (GA) was used to search the optimal input space of the trained ANN model and find the corresponding PCA yield. The optimum composition was found to be: glucose 34.3 g L(-1), soy peptone 43.2 g L(-1), NaCl 5.7 g L(-1), and the predictive maximum PCA yield reached 980.1 microg mL(-1). The optimized medium allowed PCA yield to be increased from 673.3 to 966.7 microg mL(-1) after verification experiment tests. Additionally, PCA fermentation kinetics was investigated. Kinetic models based on the modified Logistic and Luedeking-Piret equations were developed, providing a good description of temporal variations of biomass (X), product (P), and substrate (S) in PCA fermentation.

  14. Effect of corn plant on survival and phenanthrene degradation capacity of Pseudomonas sp. UG14LR in two soils.

    PubMed

    Chouychai, Waraporn; Thongkukiatkul, Amporn; Upatham, Suchart; Pokethitiyook, Prayad; Kruatrachue, Maleeya; Lee, Hung

    2012-07-01

    A study was undertaken to assess if corn (Zea mays L.) can enhance phenanthrene degradation in two soils inoculated with Pseudomonas sp. UG14Lr. Corn increased the number of UG14Lr cells in both soils, especially in the acidic soiL Phenanthrene was degraded to a greater extent in UG14Lr-inoculated or corn-planted soils than uninoculated and unplanted soils. The spiked phenanthrene was completely removed within 70 days in all the treatments in slightly alkaline soil. However, in acidic soil, complete phenanthrene removal was found only in the corn-planted treatments. The shoot and root lengths of corn grown in UG14Lr-inoculated soils were not different from those in non-inoculated soil between the treatments. The results showed that in unplanted soil, low pH adversely affected the survival and phenanthrene degradation ability of UG14Lr. Planting of corn significantly enhanced the survival of UG14Lr cells in both the bulk and rhizospheric soil, and this in turn significantly improved phenanthrene degradation in acidic soil. Re-inoculation of UG14Lr in the acidic soil increased the number of UG14Lr cells and enhanced phenanthrene degradation in unplanted soil. However, in corn-planted acidic soils, re-inoculation of UG14Lr did not further enhance the already active phenanthrene degradation occurring in both the bulk or rhizospheric soils.

  15. Isolation, plant colonization potential, and phenanthrene degradation performance of the endophytic bacterium Pseudomonas sp. Ph6-gfp.

    PubMed

    Sun, Kai; Liu, Juan; Gao, Yanzheng; Jin, Li; Gu, Yujun; Wang, Wanqing

    2014-06-26

    This investigation provides a novel method of endophyte-aided removal of polycyclic aromatic hydrocarbons (PAHs) from plant bodies. A phenanthrene-degrading endophytic bacterium Pseudomonas sp. Ph6 was isolated from clover (Trifolium pratense L.) grown in a PAH-contaminated site. After being marked with the GFP gene, the colonization and distribution of strain Ph6-gfp was directly visualized in plant roots, stems, and leaves for the first time. After ryegrass (Lolium multiflorum Lam.) roots inoculation, strain Ph6-gfp actively and internally colonized plant roots and transferred vertically to the shoots. Ph6-gfp had a natural capacity to cope with phenanthrene in vitro and in planta. Ph6-gfp degraded 81.1% of phenanthrene (50 mg · L(-1)) in a culture solution within 15 days. The inoculation of plants with Ph6-gfp reduced the risks associated with plant phenanthrene contamination based on observations of decreased concentration, accumulation, and translocation factors of phenanthrene in ryegrass. Our results will have important ramifications in the assessment of the environmental risks of PAHs and in finding ways to circumvent plant PAH contamination.

  16. Isolation, plant colonization potential, and phenanthrene degradation performance of the endophytic bacterium Pseudomonas sp. Ph6-gfp

    NASA Astrophysics Data System (ADS)

    Sun, Kai; Liu, Juan; Gao, Yanzheng; Jin, Li; Gu, Yujun; Wang, Wanqing

    2014-06-01

    This investigation provides a novel method of endophyte-aided removal of polycyclic aromatic hydrocarbons (PAHs) from plant bodies. A phenanthrene-degrading endophytic bacterium Pseudomonas sp. Ph6 was isolated from clover (Trifolium pratense L.) grown in a PAH-contaminated site. After being marked with the GFP gene, the colonization and distribution of strain Ph6-gfp was directly visualized in plant roots, stems, and leaves for the first time. After ryegrass (Lolium multiflorum Lam.) roots inoculation, strain Ph6-gfp actively and internally colonized plant roots and transferred vertically to the shoots. Ph6-gfp had a natural capacity to cope with phenanthrene in vitro and in planta. Ph6-gfp degraded 81.1% of phenanthrene (50 mg.L-1) in a culture solution within 15 days. The inoculation of plants with Ph6-gfp reduced the risks associated with plant phenanthrene contamination based on observations of decreased concentration, accumulation, and translocation factors of phenanthrene in ryegrass. Our results will have important ramifications in the assessment of the environmental risks of PAHs and in finding ways to circumvent plant PAH contamination.

  17. Purification and properties of NADH-ferredoxinNAP reductase, a component of naphthalene dioxygenase from Pseudomonas sp. strain NCIB 9816.

    PubMed Central

    Haigler, B E; Gibson, D T

    1990-01-01

    Cells of Pseudomonas sp. strain NCIB 9816, after growth with naphthalene or salicylate, contain a multicomponent enzyme system that oxidizes naphthalene to cis-(1R,2S)-dihydroxy-1,2-dihydronaphthalene. We purified one of these components to homogeneity and found it to be an iron-sulfur flavoprotein that loses the flavin cofactor during purification. Dialysis against flavin adenine dinucleotide (FAD) showed that the enzyme bound 1 mol of FAD per mol of enzyme protein. The enzyme consisted of a single polypeptide with an apparent molecular weight of 36,300. The purified protein contained 1.8 g-atoms of iron and 2.0 g-atoms of acid-labile sulfur and showed absorption maxima at 278, 340, 420, and 460 nm, with a broad shoulder at 540 nm. The purified enzyme catalyzed the reduction of cytochrome c, dichlorophenolindophenol, Nitro Blue Tetrazolium, and ferricyanide. These activities were enhanced in the presence of added FAD. The ability of the enzyme to catalyze the reduction of the ferredoxin involved in naphthalene reduction and other electron acceptors indicates that it functions as an NAD(P)H-oxidoreductase in the naphthalene dioxygenase system. The results suggest that naphthalene dioxygenase requires two proteins with three redox groups to transfer electrons from NADH to the terminal oxygenase. Images FIG. 3 PMID:2294092

  18. Chlorpyrifos pollution: its effect on brain acetylcholinesterase activity in rat and treatment of polluted soil by indigenous Pseudomonas sp.

    PubMed

    Sharma, Shelly; Singh, Partap Bir; Chadha, Pooja; Saini, Harvinder Singh

    2017-01-01

    The study was aimed to evaluate the levels of chlorpyrifos (CPF) pollution in agricultural soil of Punjab, India, its detrimental effects on acetylcholinesterase (AChE) activity in rat brain and bioremediation of soils polluted with CPF using indigenous and adapted bacterial lab isolate. The analysis revealed that soil samples of Bathinda and Amritsar regions are highly contaminated with chlorpyrifos showing 19 to 175 mg/kg concentrations of CPF. The non-targeted animals may get poisoned with CPF by its indirect dermal absorption, inhalation of toxic fumes and regular consumption of soiled food grains. The study indicated that even the lowermost concentrations of CPF, 19 and 76 mg/kg of soil found in the Amritsar and Bathinda regions respectively can significantly inhibit the AChE activity in rat brain within 24 h of its treatment. This represents the antagonistic effect of CPF on AChE which is a prime neurotransmitter present in all living beings including humans. In light of this, an attempt was made to remediate the polluted soil, a major reservoir of CPF, using Pseudomonas sp. (ChlD), an indigenous bacterial isolate. The culture efficiently degraded 10 to 100 mg/kg chlorpyrifos supplemented in the soil and utilized it as sole source of carbon and energy for its growth. Thus, this study provides a detailed insight regarding the level of CPF pollution in Punjab, its detrimental effects on mammals and bio-based solution to remediate the sites polluted with CPF.

  19. Insights into functional and evolutionary analysis of carbaryl metabolic pathway from Pseudomonas sp. strain C5pp

    PubMed Central

    Trivedi, Vikas D.; Jangir, Pramod Kumar; Sharma, Rakesh; Phale, Prashant S.

    2016-01-01

    Carbaryl (1-naphthyl N-methylcarbamate) is a most widely used carbamate pesticide in the agriculture field. Soil isolate, Pseudomonas sp. strain C5pp mineralizes carbaryl via 1-naphthol, salicylate and gentisate, however the genetic organization and evolutionary events of acquisition and assembly of pathway have not yet been studied. The draft genome analysis of strain C5pp reveals that the carbaryl catabolic genes are organized into three putative operons, ‘upper’, ‘middle’ and ‘lower’. The sequence and functional analysis led to identification of new genes encoding: i) hitherto unidentified 1-naphthol 2-hydroxylase, sharing a common ancestry with 2,4-dichlorophenol monooxygenase; ii) carbaryl hydrolase, a member of a new family of esterase; and iii) 1,2-dihydroxy naphthalene dioxygenase, uncharacterized type-II extradiol dioxygenase. The ‘upper’ pathway genes were present as a part of a integron while the ‘middle’ and ‘lower’ pathway genes were present as two distinct class-I composite transposons. These findings suggest the role of horizontal gene transfer event(s) in the acquisition and evolution of the carbaryl degradation pathway in strain C5pp. The study presents an example of assembly of degradation pathway for carbaryl. PMID:27924916

  20. SecG is required for antibiotic activities of Pseudomonas sp. YL23 against Erwinia amylovora and Dickeya chrysanthemi.

    PubMed

    Liu, Youzhou; Baird, Sonya M; Qiao, Junqing; Du, Yan; Lu, Shi-En

    2015-05-01

    Strain YL23 was isolated from soybean root tips and identified to be Pseudomonas sp. This strain showed broad-spectrum antibacterial activity against bacterial pathogens that are economically important in agriculture. To characterize the genes dedicated to antibacterial activities against microbial phytopathogens, a Tn5-mutation library of YL23 was constructed. Plate bioassays revealed that the mutant YL23-93 lost its antibacterial activities against Erwinia amylovora and Dickeya chrysanthemi as compared with its wild type strain. Genetic and sequencing analyses localized the transposon in a homolog of the secG gene in the mutant YL23-93. Constitutive expression plasmid pUCP26-secG was constructed and electroporated into the mutant YL23-93. Introduction of the plasmid pUCP26-secG restored antibacterial activities of the mutant YL23-93 to E. amylovora and D. chrysanthemi. As expected, empty plasmid pUCP26 could not complement the phenotype of the antibacterial activity in the mutant. Thus the secG gene, belonging to the Sec protein translocation system, is required for antibacterial activity of strain YL23 against E. amylovora and D. chrysanthemi.

  1. Degradation of phenol and toxicity of phenolic compounds: a comparison of cold-tolerant Arthrobacter sp. and mesophilic Pseudomonas putida.

    PubMed

    Margesin, Rosa; Bergauer, Philipp; Gander, Silvia

    2004-06-01

    Phenol degradation efficiency of cold-tolerant Arthrobacter sp. AG31 and mesophilic Pseudomonas putida DSM6414 was compared. The cold-tolerant strain was cultivated at 10 degrees C, while the mesophile was grown at 25 degrees C. Both strains degraded 200 mg and 400 mg phenol/l within 48-72 h of cultivation, but the cold-tolerant strain produced more biomass than the mesophile. Both strains oxidized catechol by the ortho type of ring fission. Catechol 1,2 dioxygenase (C1,2D) activity was found intra- and extracellularly in the absence and in the presence of phenol. In the presence of 200 mg phenol/l, C1,2D activity of the mesophile was about 1.5- to 2-fold higher than that of the cold-tolerant strain. However, an initial phenol concentration of 400 mg/l resulted in a comparable enzyme activity of the cold-tolerant and the mesophilic strain. The two strains differed significantly in their toxicity pattern towards 12 aromatic (mostly phenolic) compounds at different growth temperatures, which was determined via growth inhibition in the presence of nutrients and toxicants. For the cold-tolerant strain, toxicity was significantly lower at 10 degrees C than at 25 degrees C. The mesophile showed a significantly lower susceptibility to high hydrocarbon concentrations when grown at 25 degrees C compared to 10 degrees C.

  2. Structural and physicochemical characterization of crude biosurfactant produced by Pseudomonas aeruginosa SP4 isolated from petroleum-contaminated soil.

    PubMed

    Pornsunthorntawee, Orathai; Wongpanit, Panya; Chavadej, Sumaeth; Abe, Masahiko; Rujiravanit, Ratana

    2008-04-01

    Pseudomonas aeruginosa strain SP4, isolated from petroleum-contaminated soil in Thailand, was used to produce a biosurfactant from a nutrient broth with palm oil as the carbon source. The key components of the crude biosurfactant were fractionated by using HPLC-ELSD technique. With the use of ATR-FTIR spectroscopy, in combination with (1)H NMR and MS analyses, chemical structures of the fractionated components of the crude biosurfactant were identified as rhamnolipid species. When compared to synthetic surfactants, including Pluronic F-68, which is a triblock nonionic surfactant containing poly(ethylene oxide) and poly(propylene oxide), and sodium dodecyl sulfate, the crude biosurfactant showed comparable physicochemical properties, in terms of the surface activities. The crude biosurfactant reduced the surface tension of pure water to 29.0 mN/m with a critical micelle concentration of approximately 200 mg/l, and it exhibited good thermal and pH stability. The crude biosurfactant also formed stable water-in-oil microemulsions with crude oil and various types of vegetable oils, but not with short-chain hydrocarbons.

  3. Adaptation of Pseudomonas sp. Strain 7-6 to Quaternary Ammonium Compounds and Their Degradation via Dual Pathways▿

    PubMed Central

    Takenaka, Shinji; Tonoki, Takashi; Taira, Kazuya; Murakami, Shuichiro; Aoki, Kenji

    2007-01-01

    Pseudomonas sp. strain 7-6, isolated from active sludge obtained from a wastewater facility, utilized a quaternary ammonium surfactant, n-dodecyltrimethylammonium chloride (DTAC), as its sole carbon, nitrogen, and energy source. When initially grown in the presence of 10 mM DTAC medium, the isolate was unable to degrade DTAC. The strain was cultivated in gradually increasing concentrations of the surfactant until continuous exposure led to high tolerance and biodegradation of the compound. Based on the identification of five metabolites by gas chromatography-mass spectrometry analysis, two possible pathways for DTAC metabolism were proposed. In pathway 1, DTAC is converted to lauric acid via n-dodecanal with the release of trimethylamine; in pathway 2, DTAC is converted to lauric acid via n-dodecyldimethylamine and then n-dodecanal with the release of dimethylamine. Among the identified metabolites, the strain precultivated on DTAC medium could utilize n-dodecanal and lauric acid as sole carbon sources and trimethylamine and dimethylamine as sole nitrogen sources, but it could not efficiently utilize n-dodecyldimethylamine. These results indicated pathway 1 is the main pathway for the degradation of DTAC. PMID:17261523

  4. Proteomic analysis of sulfur-nitrogen-carbon removal by Pseudomonas sp. C27 under micro-aeration condition.

    PubMed

    Guo, Hongliang; Chen, Chuan; Lee, Duu-Jong; Wang, Aijie; Ren, Nanqi

    2014-03-05

    Pseudomonas sp. C27 is a facultative autotrophic bacterium (FAB) that can effectively conduct mixotrophic and heterotrophic denitrifying sulfide removal (DSR) reactions under anaerobic condition using organic matters and sulfide as electron donors. Micro-aeration was proposed to enhance DSR reaction by FAB; however, there is no experimental proof on the effects of micro-aeration on capacity of denitrifying sulfide removal of FAB on proteomic levels. The proteome in total C27 cell extracts was observed by two-dimensional gel electrophoresis. Differentially expressed protein spots and specifically expressed protein spots were identified by MALDI TOF/TOF MS. We identified 55 microaerobic-responsive protein spots, representing 55 unique proteins. Hierarchical clustering analysis revealed that 75% of the proteins were up-regulated, and 5% of the proteins were specifically expressed under micro-aerobic conditions. These enzymes were mainly involved in membrane transport, protein folding and metabolism. The noted expression changes of the microaerobic-responsive proteins suggests that C27 strain has a highly efficient enzyme system to conduct DSR reactions under micro-aerobic condition. Additionally, micro-aeration can increase the rates of protein synthesis and cell growth, and enhance cell defensive system of the strain.

  5. Comparative studies of genes encoding thermostable L-2-halo acid dehalogenase from Pseudomonas sp. strain YL, other dehalogenases, and two related hypothetical proteins from Escherichia coli.

    PubMed Central

    Nardi-Dei, V; Kurihara, T; Okamura, T; Liu, J Q; Koshikawa, H; Ozaki, H; Terashima, Y; Esaki, N; Soda, K

    1994-01-01

    We have determined the nucleotide sequence of the gene encoding thermostable L-2-halo acid dehalogenase (L-DEX) from the 2-chloroacrylate-utilizable bacterium Pseudomonas sp. strain YL. The open reading frame consists of 696 nucleotides corresponding to 232 amino acid residues. The protein molecular weight was estimated to be 26,179, which was in good agreement with the subunit molecular weight of the enzyme. The gene was efficiently expressed in the recombinant Escherichia coli cells: the amount of L-DEX corresponds to about 49% of the total soluble proteins. The predicted amino acid sequence showed a high level of similarity to those of L-DEXs from other bacterial strains and haloacetate dehalogenase H-2 from Moraxella sp. strain B (38 to 57% identity) but a very low level of similarity to those of haloacetate dehalogenase H-1 from Moraxella sp. strain B (10%) and haloalkane dehalogenase from Xanthobacter autotrophicus GJ10 (12%). By searching the protein amino acid sequence database, we found two E. coli hypothetical proteins similar to the Pseudomonas sp. strain YL L-DEX (21 to 22%). PMID:7944368

  6. The effect of toxic malachite green on the bacterial community in Antarctic soil and the physiology of malachite green-degrading Pseudomonas sp. MGO.

    PubMed

    Jung, Jaejoon; Seo, Hyoju; Lee, Se Hee; Jeon, Che Ok; Park, Woojun

    2013-05-01

    The effects of malachite green (MG) on the bacterial community in Antarctic soil were assessed. Culture-independent community analysis using 16S rRNA gene pyrosequencing showed that, in the presence of MG, the relative abundance of Pseudomonas dramatically increased from 2.2 % to 36.6 % (16.6-fold), and Pseudomonas became the predominant genus. The reduction in bacterial biodiversity was demonstrated by diversity indices and rarefaction curves. MG-degrading Pseudomonas sp. MGO was isolated from Antarctic soil. MG tolerance and decolorization activity were confirmed by growth, spectrophotometric, high-performance liquid chromatography, and thin-layer chromatography analyses in high MG concentrations. Our data showed that the decolorization process occurred via biodegradation, while biosorption also occurred after some time during the fed-batch decolorization process. Significant inductions in laccase, nicotinamide adenine dinucleotide-2,6 dichlorophenol indophenol reductase, and MG reductase activities suggested their involvement in the decolorization process. We also showed that the high tolerance of strain MGO to toxic MG might be mediated by upregulation of oxidative stress defense systems such as superoxide dismutase and protease. Collectively, these results demonstrated the response of the Antarctic soil bacterial community to MG and provided insight into the molecular mechanism of MG-tolerant Pseudomonas strains isolated from Antarctic soil.

  7. Aerobic Degradation of N-Methyl-4-Nitroaniline (MNA) by Pseudomonas sp. Strain FK357 Isolated from Soil

    PubMed Central

    Khan, Fazlurrahman; Vyas, Bhawna; Pal, Deepika; Cameotra, Swaranjit Singh

    2013-01-01

    N-Methyl-4-nitroaniline (MNA) is used as an additive to lower the melting temperature of energetic materials in the synthesis of insensitive explosives. Although the biotransformation of MNA under anaerobic condition has been reported, its aerobic microbial degradation has not been documented yet. A soil microcosms study showed the efficient aerobic degradation of MNA by the inhabitant soil microorganisms. An aerobic bacterium, Pseudomonas sp. strain FK357, able to utilize MNA as the sole carbon, nitrogen, and energy source, was isolated from soil microcosms. HPLC and GC-MS analysis of the samples obtained from growth and resting cell studies showed the formation of 4-nitroaniline (4-NA), 4-aminophenol (4-AP), and 1, 2, 4-benzenetriol (BT) as major metabolic intermediates in the MNA degradation pathway. Enzymatic assay carried out on cell-free lysates of MNA grown cells confirmed N-demethylation reaction is the first step of MNA degradation with the formation of 4-NA and formaldehyde products. Flavin-dependent transformation of 4-NA to 4-AP in cell extracts demonstrated that the second step of MNA degradation is a monooxygenation. Furthermore, conversion of 4-AP to BT by MNA grown cells indicates the involvement of oxidative deamination (release of NH2 substituent) reaction in third step of MNA degradation. Subsequent degradation of BT occurs by the action of benzenetriol 1, 2-dioxygenase as reported for the degradation of 4-nitrophenol. This is the first report on aerobic degradation of MNA by a single bacterium along with elucidation of metabolic pathway. PMID:24116023

  8. Purification and characterization of the oxygenase component of biphenyl 2,3-dioxygenase from Pseudomonas sp. strain LB400.

    PubMed Central

    Haddock, J D; Gibson, D T

    1995-01-01

    The iron-sulfur protein of biphenyl 2,3-dioxygenase (ISPBPH) was purified from Pseudomonas sp. strain LB400. The protein is composed of a 1:1 ratio of a large (alpha) subunit with an estimated molecular weight of 53,300 and a small (beta) subunit with an estimated molecular weight of 27,300. The native molecular weight was 209,000, indicating that the protein adopts an alpha 3 beta 3 native conformation. Measurements of iron and acid-labile sulfide gave 2 mol of each per mol of alpha beta heterodimer. The absorbance spectrum showed peaks at 325 and 450 nm with a broad shoulder at 550 nm. The spectrum was bleached upon reduction of the protein with NADPH in the presence of catalytic amounts of ferredoxinBPH and ferredoxinBPH oxidoreductase. The electron paramagnetic resonance spectrum of the reduced protein showed three signals at gx = 1.74, gy = 1.92, and gz = 2.01. These properties are characteristic of proteins that contain a Rieske-type [2Fe-2S] center. Biphenyl was oxidized to cis-(2R,3S)-dihydroxy-1-phenylcyclohexa-4,6-diene by ISPBPH in the presence of ferredoxinBPH, ferredoxinBPH oxidoreductase, NADPH, and ferrous iron. Naphthalene was also oxidized to a cis-dihydrodiol, but only 3% was converted to product under the same conditions that gave 92% oxidation of biphenyl. Benzene, toluene, 2,5-dichlorotoluene, carbazole, and dibenzothiophene were not oxidized. ISPBPH is proposed to be the terminal oxygenase component of biphenyl 2,3-dioxygenase where substrate binding and oxidation occur via addition of molecular oxygen and two reducing equivalents. PMID:7592331

  9. Does S-Metolachlor Affect the Performance of Pseudomonas sp. Strain ADP as Bioaugmentation Bacterium for Atrazine-Contaminated Soils?

    PubMed Central

    Viegas, Cristina A.; Costa, Catarina; André, Sandra; Viana, Paula; Ribeiro, Rui; Moreira-Santos, Matilde

    2012-01-01

    Atrazine (ATZ) and S-metolachlor (S-MET) are two herbicides widely used, often as mixtures. The present work examined whether the presence of S-MET affects the ATZ-biodegradation activity of the bioaugmentation bacterium Pseudomonas sp. strain ADP in a crop soil. S-MET concentrations were selected for their relevance in worst-case scenarios of soil contamination by a commercial formulation containing both herbicides. At concentrations representative of application of high doses of the formulation (up to 50 µg g−1 of soil, corresponding to a dose approximately 50× higher than the recommended field dose (RD)), the presence of pure S-MET significantly affected neither bacteria survival (∼107 initial viable cells g−1 of soil) nor its ATZ-mineralization activity. Consistently, biodegradation experiments, in larger soil microcosms spiked with 20× or 50×RD of the double formulation and inoculated with the bacterium, revealed ATZ to be rapidly (in up to 5 days) and extensively (>96%) removed from the soil. During the 5 days, concentration of S-MET decreased moderately to about 60% of the initial, both in inoculated and non-inoculated microcosms. Concomitantly, an accumulation of the two metabolites S-MET ethanesulfonic acid and S-MET oxanilic acid was found. Despite the dissipation of almost all the ATZ from the treated soils, the respective eluates were still highly toxic to an aquatic microalgae species, being as toxic as those from the untreated soil. We suggest that this high toxicity may be due to the S-MET and/or its metabolites remaining in the soil. PMID:22615921

  10. Transformation of Isopropylamine to l-Alaninol by Pseudomonas sp. Strain KIE171 Involves N-Glutamylated Intermediates

    PubMed Central

    de Azevedo Wäsch, Susana I.; van der Ploeg, Jan R.; Maire, Tere; Lebreton, Alice; Kiener, Andreas; Leisinger, Thomas

    2002-01-01

    Pseudomonas sp. strain KIE171 was able to grow with isopropylamine or l-alaninol [S-(+)-2-amino-1-propanol] as the sole carbon source, but not with d-alaninol. To investigate the hypothesis that l-alaninol is an intermediate in the degradation of isopropylamine, two mini-Tn5 mutants unable to utilize both isopropylamine and l-alaninol were isolated. Whereas mutant KIE171-BI transformed isopropylamine to l-alaninol, mutant KIE171-BII failed to do so. The two genes containing a transposon insertion were cloned, and the DNA regions flanking the insertions were sequenced. Two clusters, one comprising eight ipu (isopropylamine utilization) genes (ipuABCDEFGH) and the other encompassing two genes (ipuI and orf259), were identified. Comparisons of sequences of the deduced Ipu proteins and those in the database suggested that isopropylamine is transported into the cytoplasm by a putative permease, IpuG. The next step, the formation of γ-glutamyl-isopropylamide from isopropylamine, ATP, and l-glutamate, was shown to be catalyzed by IpuC, a γ-glutamylamide synthetase. γ-Glutamyl-isopropylamide is then subjected to stereospecific monooxygenation by the hypothetical four-component system IpuABDE, thereby yielding γ-glutamyl-l-alaninol [γ(l-glutamyl)-l-hydroxy-isopropylamide]. Enzymatic hydrolysis by a hydrolase, IpuF, was shown to finally liberate l-alaninol and to regenerate l-glutamate. No gene(s) encoding an enzyme for the next step in the degradation of isopropylamine was found in the ipu clusters. Presumably, l-alaninol is oxidized by an alcohol dehydrogenase to yield l-2-aminopropionaldehyde or it is deaminated by an ammonia lyase to propionaldehyde. Genetic evidence indicated that the aldehyde formed is then further oxidized by the hypothetical aldehyde dehydrogenases IpuI and IpuH to either l-alanine or propionic acid, compounds which can be processed by reactions of the intermediary metabolism. PMID:11976110

  11. 'Pseudomonas saudimassiliensis' sp. nov. a new bacterial species isolated from air samples in the urban environment of Makkah, Saudi Arabia.

    PubMed

    Azhar, E I; Papadioti, A; Bibi, F; Ashshi, A M; Raoult, D; Angelakis, E

    2017-03-01

    We report here the main characteristics of 'Pseudomonas saudimassiliensis' strain 12M76_air(T) (CSUR P1220), a new species of the Pseudomonas genus that was isolated from air samples in the city environment of Makkah, Saudi Arabia, during the pilgrim period of Hajj 2012.

  12. Characterization of Fluorescent Siderophore-Mediated Iron Uptake in Pseudomonas sp. Strain M114: Evidence for the Existence of an Additional Ferric Siderophore Receptor.

    PubMed

    Morris, J; O'sullivan, D J; Koster, M; Leong, J; Weisbeek, P J; O'gara, F

    1992-02-01

    In Pseudomonas sp. strain M114, the outer membrane receptor for ferric pseudobactin M114 was shown to transport ferric pseudobactins B10 and A225, in addition to its own. The gene encoding this receptor, which was previously cloned on pCUP3, was localized by Tn5 mutagenesis to a region comprising >1.6 kb of M114 DNA. A mutant (strain M114R1) lacking this receptor was then created by a marker exchange technique. Characterization of this mutant by using purified pseudobactin M114 in radiolabeled ferric iron uptake studies confirmed that it was completely unable to utilize this siderophore for acquisition of iron. In addition, it lacked an outer membrane protein band of 89 kDa when subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis. As a result, growth of the mutant was severely restricted under low-iron conditions. However, this phenotype was reversed in the presence of another fluorescent siderophore (pseudobactin MT3A) from Pseudomonas sp. strain MT3A, suggesting the presence of a second receptor in strain M114. Furthermore, wild-type Pseudomonas sp. strain B24 was not able to utilize ferric pseudobactin MT3A, and this phenotype was not reversed upon expression of the M114 receptor encoded on pCUP3. However, a cosmid clone (pMS1047) that enabled strain B24 to utilize ferric pseudobactin MT3A was isolated from an M114 gene bank. Radiolabel transport assays with purified pseudobactin MT3A confirmed this event. Plasmid pMS1047 was shown to encode an outer membrane protein of 81 kDa in strain B24 under iron-limiting conditions; this protein corresponds to a similar protein in strain M114.

  13. Pseudomonas aestusnigri sp. nov., isolated from crude oil-contaminated intertidal sand samples after the Prestige oil spill.

    PubMed

    Sánchez, David; Mulet, Magdalena; Rodríguez, Ana C; David, Zoyla; Lalucat, Jorge; García-Valdés, Elena

    2014-03-01

    Strains VGXO14(T) and Vi1 were isolated from the Atlantic intertidal shore from Galicia, Spain, after the Prestige oil spill. Both strains were Gram-negative rod-shaped bacteria with one polar inserted flagellum, strictly aerobic, and able to grow at 18-37°C, pH 6-10 and 2-10% NaCl. A preliminary analysis of the 16S rRNA and the partial rpoD gene sequences indicated that these strains belonged to the Pseudomonas genus but were distinct from any known Pseudomonas species. A polyphasic taxonomic approach including phylogenetic, chemotaxonomic, phenotypic and genotypic data confirmed that the strains belonged to the Pseudomonas pertucinogena group. In a multilocus sequence analysis, the similarity of VGXO14(T) and Vi1 to the closest type strain of the group, Pseudomonas pachastrellae, was 90.4%, which was lower than the threshold of 97% established to discriminate species in the Pseudomonas genus. The DNA-DNA hybridisation similarity between strains VGXO14(T) and Vi1 was 79.6%, but below 70% with the type strains in the P. pertucinogena group. Therefore, the strains should be classified within the genus Pseudomonas as a novel species, for which the name Pseudomonas aestusnigri is proposed. The type strain is VGXO14(T) (=CCUG 64165(T)=CECT 8317(T)).

  14. Draft genome sequence analysis of a Pseudomonas putida W15Oct28 strain with antagonistic activity to Gram-positive and Pseudomonas sp. pathogens.

    PubMed

    Ye, Lumeng; Hildebrand, Falk; Dingemans, Jozef; Ballet, Steven; Laus, George; Matthijs, Sandra; Berendsen, Roeland; Cornelis, Pierre

    2014-01-01

    Pseudomonas putida is a member of the fluorescent pseudomonads known to produce the yellow-green fluorescent pyoverdine siderophore. P. putida W15Oct28, isolated from a stream in Brussels, was found to produce compound(s) with antimicrobial activity against the opportunistic pathogens Staphylococcus aureus, Pseudomonas aeruginosa, and the plant pathogen Pseudomonas syringae, an unusual characteristic for P. putida. The active compound production only occurred in media with low iron content and without organic nitrogen sources. Transposon mutants which lost their antimicrobial activity had the majority of insertions in genes involved in the biosynthesis of pyoverdine, although purified pyoverdine was not responsible for the antagonism. Separation of compounds present in culture supernatants revealed the presence of two fractions containing highly hydrophobic molecules active against P. aeruginosa. Analysis of the draft genome confirmed the presence of putisolvin biosynthesis genes and the corresponding lipopeptides were found to contribute to the antimicrobial activity. One cluster of ten genes was detected, comprising a NAD-dependent epimerase, an acetylornithine aminotransferase, an acyl CoA dehydrogenase, a short chain dehydrogenase, a fatty acid desaturase and three genes for a RND efflux pump. P. putida W15Oct28 genome also contains 56 genes encoding TonB-dependent receptors, conferring a high capacity to utilize pyoverdines from other pseudomonads. One unique feature of W15Oct28 is also the presence of different secretion systems including a full set of genes for type IV secretion, and several genes for type VI secretion and their VgrG effectors.

  15. Sequence determination and analysis of three plasmids of Pseudomonas sp. GLE121, a psychrophile isolated from surface ice of Ecology Glacier (Antarctica).

    PubMed

    Dziewit, Lukasz; Grzesiak, Jakub; Ciok, Anna; Nieckarz, Marta; Zdanowski, Marek K; Bartosik, Dariusz

    2013-09-01

    Pseudomonas sp. GLE121 (a psychrophilic Antarctic strain) carries three plasmids: pGLE121P1 (6899 bp), pGLE121P2 (8330 bp) and pGLE121P3 (39,583 bp). Plasmids pGLE121P1 and pGLE121P2 show significant sequence similarity to members of the IncP-9 and IncP-7 incompatibility groups, respectively, while the largest replicon, pGLE121P3, is highly related to plasmid pNCPPB880-40 of Pseudomonas syringae pathovar tomato NCPPB880. All three plasmids have a narrow host range, limited to members of the genus Pseudomonas. Plasmid pGLE121P3 encodes a conjugal transfer system, while pGLE121P1 carries only a putative MOB module, conserved in many mobilizable plasmids. Plasmid pGLE121P3 contains an additional load of genetic information, including a pair of genes with homology to the rulAB operon, responsible for ultraviolet radiation (UVR) tolerance. Given the increasing UV exposure in Antarctic regions, the expression of these genes is likely to be an important adaptive response.

  16. Structural Adaptation of Cold-Active RTX Lipase from Pseudomonas sp. Strain AMS8 Revealed via Homology and Molecular Dynamics Simulation Approaches

    PubMed Central

    Mohamad Ali, Mohd. Shukuri; Mohd Fuzi, Siti Farhanie; Ganasen, Menega; Abdul Rahman, Raja Noor Zaliha Raja; Basri, Mahiran; Salleh, Abu Bakar

    2013-01-01

    The psychrophilic enzyme is an interesting subject to study due to its special ability to adapt to extreme temperatures, unlike typical enzymes. Utilizing computer-aided software, the predicted structure and function of the enzyme lipase AMS8 (LipAMS8) (isolated from the psychrophilic Pseudomonas sp., obtained from the Antarctic soil) are studied. The enzyme shows significant sequence similarities with lipases from Pseudomonas sp. MIS38 and Serratia marcescens. These similarities aid in the prediction of the 3D molecular structure of the enzyme. In this study, 12 ns MD simulation is performed at different temperatures for structural flexibility and stability analysis. The results show that the enzyme is most stable at 0°C and 5°C. In terms of stability and flexibility, the catalytic domain (N-terminus) maintained its stability more than the noncatalytic domain (C-terminus), but the non-catalytic domain showed higher flexibility than the catalytic domain. The analysis of the structure and function of LipAMS8 provides new insights into the structural adaptation of this protein at low temperatures. The information obtained could be a useful tool for low temperature industrial applications and molecular engineering purposes, in the near future. PMID:23738333

  17. Structural adaptation of cold-active RTX lipase from Pseudomonas sp. strain AMS8 revealed via homology and molecular dynamics simulation approaches.

    PubMed

    Mohamad Ali, Mohd Shukuri; Mohd Fuzi, Siti Farhanie; Ganasen, Menega; Abdul Rahman, Raja Noor Zaliha Raja; Basri, Mahiran; Salleh, Abu Bakar

    2013-01-01

    The psychrophilic enzyme is an interesting subject to study due to its special ability to adapt to extreme temperatures, unlike typical enzymes. Utilizing computer-aided software, the predicted structure and function of the enzyme lipase AMS8 (LipAMS8) (isolated from the psychrophilic Pseudomonas sp., obtained from the Antarctic soil) are studied. The enzyme shows significant sequence similarities with lipases from Pseudomonas sp. MIS38 and Serratia marcescens. These similarities aid in the prediction of the 3D molecular structure of the enzyme. In this study, 12 ns MD simulation is performed at different temperatures for structural flexibility and stability analysis. The results show that the enzyme is most stable at 0°C and 5°C. In terms of stability and flexibility, the catalytic domain (N-terminus) maintained its stability more than the noncatalytic domain (C-terminus), but the non-catalytic domain showed higher flexibility than the catalytic domain. The analysis of the structure and function of LipAMS8 provides new insights into the structural adaptation of this protein at low temperatures. The information obtained could be a useful tool for low temperature industrial applications and molecular engineering purposes, in the near future.

  18. Biodegradation of malachite green by strain Pseudomonas sp. K9 and cloning of the tmr2 gene associated with an ISPpu12.

    PubMed

    Huan-Mei; Lian-Tai, Li; Cai-Fang, Yan; Jin-Jin, Sun; Yuan-Gao; Hong, Qing; Shun-Peng, Li

    2011-06-01

    A bacterial strain K9 capable of degrading malachite green was isolated from the sludge of the wastewater treatment system of a chemical plant. It was identified preliminarily as Pseudomonas sp. Strain K9 was also able to degrade other triphenylmethane dyes, such as Crystal Violet and Basic Fuchsin. The gene tmr2, encoding the triphenylmethane reductase, was cloned from strain K9, and functionally expressed in E. coli. A 5946-bp DNA fragment including the tmr2 gene was cloned from the genomic DNA of strain K9 by chromosome walking. Its sequence analysis showed that tmr2 was associated with a typical mobile element ISPpu12 consisting of tnpA (encoding a transposase), lspA (encoding a lipoprotein signal peptidase) and orf1 (encoding a putative MerR family regulator), orf2 (encoding a CDF family heavy metal/H(+) antiporter). This association was also found in another malachite green-degrading strain Pseudomonas sp. MDB-1, which indicated that the tmr2 gene might be a horizontally transferable gene.

  19. Crystallization and preliminary X-ray analysis of the complex of NADH and 3α-hydroxysteroid dehydrogenase from Pseudomonas sp. B-0831

    SciTech Connect

    Kataoka, Sachiyo; Nakamura, Shota; Ohkubo, Tadayasu; Ueda, Shigeru; Uchiyama, Susumu; Kobayashi, Yuji; Oda, Masayuki

    2006-06-01

    The complex of NADH and 3α-HSD from Pseudomonas sp. B-0831 has been crystallized and X-ray diffraction data have been collected to 1.8 Å resolution. The NAD(P){sup +}-dependent enzyme 3α-hydroxysteroid dehydrogenase (3α-HSD) catalyzes the reversible interconversion of hydroxyl and oxo groups at position 3 of the steroid nucleus. The complex of NADH and 3α-HSD from Pseudomonas sp. B-0831 was crystallized by the hanging-drop vapour-diffusion method. Refinement of crystallization conditions with microseeding improved the quality of the X-ray diffraction data to a resolution of 1.8 Å. The crystals belonged to the orthorhombic space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 62.46, b = 82.25, c = 86.57 Å, and contained two molecules, reflecting dimer formation of 3α-HSD, in the asymmetric unit.

  20. Isolation of a buprofezin co-metabolizing strain of Pseudomonas sp. DFS35-4 and identification of the buprofezin transformation pathway.

    PubMed

    Chen, Kai; Liu, Xiao-Mei; Li, Rong; Liu, Yuan; Hu, Hai; Li, Shun-Peng; Jiang, Jian-Dong

    2011-11-01

    Buprofezin is a widely used insecticide that has caused environmental pollution in many areas. However, biodegradation of buprofezin by pure cultures has not been extensively studied, and the transformation pathway of buprofezin remains unclear. In this paper, a buprofezin co-metabolizing strain of DFS35-4 was isolated from a buprofezin-polluted soil in China. Strain DFS35-4 was preliminarily identified as Pseudomonas sp. based on its morphological, physiological, and biochemical properties, as well as 16S rRNA gene analysis. In the presence of 2.0 g l(-1) sodium citrate, strain DFS35-4 degraded over 70% of 50 mg l(-1) buprofezin in 3 days. Strain DFS35-4 efficiently degraded buprofezin in the pH range of 5.0-10.0 and at temperatures between 20 and 30°C. Three metabolites, 2-imino-5-phenyl-3-(propan-2-yl)-1,3,5-thiadiazinan-4-one, 2-imino-5-phenyl-1,3,5-thiadiazinan-4-one, and methyl(phenyl) carbamic acid, were identified during the degradation of buprofezin using gas chromatography-mass spectrometry (GC-MS) and tandem mass spectrometry (MS/MS). A partial transformation pathway of buprofezin in Pseudomonas sp. DFS35-4 was proposed based on these metabolites.

  1. Gene cloning, structural gene and promoter identification, and active assay of the phosphatidylcholine synthase of Pseudomonas sp. strain 593.

    PubMed

    He, Huoguang; Wu, Bin; Xiong, Min; Li, Yang; Wu, Wenhua; Wang, Xingguo

    2011-10-01

    Pseudomonas sp. strain 593, a soil bacterium, is able to use exogenous choline to synthesize phosphatidylcholine via phosphatidylcholine synthase (Pcs). A 2020 bp DNA fragment that hybridized to a Pcs probe was cloned. This fragment contained a large open reading frame (ORF) with two potential ATG start sites that would encode for 293 and 231 amino acid proteins. Fragments containing the two ORFs encoded Pcs when they were inserted into the expression vector pET23a and expressed under the control of the T7 promoter in Escherichia coli BL21(DE3) pLysS. However, when the two ORFs were inserted into the cloning vector pMD18-T and expressed without control of the plasmid promoter in E. coli DH5α, only the larger clone exhibited Pcs activity. This suggested that the larger fragment contained a native promoter driving expression of the smaller ORF. A promoter activity assay, in which DNA fragments were inserted into the promoter-probe plasmid pCB182 and β-galactosidase activity of E. coli transformants was tested, demonstrated that a promoter is indeed present in the DNA region. All results together indicate that the 696 bp ORF, not the larger 897 bp ORF, encodes the Pcs in Pseudomonas sp. strain 593 and carries a promoter in front of its 5' terminus.

  2. Biodecolorization of Reactive Black-5 by a metal and salt tolerant bacterial strain Pseudomonas sp. RA20 isolated from Paharang drain effluents in Pakistan.

    PubMed

    Hussain, Sabir; Maqbool, Zahid; Ali, Shafaqat; Yasmeen, Tahira; Imran, Muhammad; Mahmood, Faisal; Abbas, Farhat

    2013-12-01

    Discharge of untreated azo dyes contaminated textile wastewater into soil and water bodies causes severe contamination. The present study was conducted to isolate dye degrading bacterial strains from a textile industry wastewater carrying drain in the neighborhood of Faisalabad, Pakistan. Seventy six bacterial strains were initially isolated and was screened using liquid mineral salts medium spiked with Reactive Black-5 azo dye. The strain RA20 was found to be the most efficient azo dye degrading bacterial isolate and was identified by amplifying and sequencing its 16S rRNA. Analysis indicated that this strain belonged to genus Pseudomonas and was designated as Pseudomonas sp. RA20. It had the highest decolorization activity at pH 8 and 25 °C incubation temperature under static conditions using yeast extract as an additional C source. This strain was also effective in decolorizing structurally related other reactive dyes including Reactive Orange 16, Reactive Yellow 2 and Reactive Red 120 but with varying efficacy. RA20 decolorized Reactive Black-5 significantly in the presence of up to 30 g L⁻¹ NaCl; however, the decolorization rate was significantly (p≤0.05) reduced beyond this salt concentration. Moreover, this bacterial strain also exhibited moderate tolerance to different heavy metals including zinc (Zn), cadmium (Cd), chromium (Cr), lead (Pb) and copper (Cu). RA20 also decolorized Reactive Black-5 in the presence of a mixture of the selected heavy metals depending upon their concentrations. This study highlights the importance of Pseudomonas sp. RA20 as a prospective biological resource for bioremediation of water and soils contaminated with azo dyes.

  3. Molecular and biochemical characteristics of β-propeller phytase from marine Pseudomonas sp. BS10-3 and its potential application for animal feed additives.

    PubMed

    Nam, Seung-Jeung; Kim, Young-Ok; Ko, Tae-Kyung; Kang, Jin-Ku; Chun, Kwang-Hoon; Auh, Joong-Hyuck; Lee, Chul-Soon; Lee, In-Kyu; Park, Sunghoon; Oh, Byung-Chul

    2014-10-01

    Phytate is an antinutritional factor that impacts the bioavailability of essential minerals such as Ca(2+), Mg(2+), Mn(2+), Zn(2+), and Fe(2+) by forming insoluble mineral-phytate salts. These insoluble mineral-phytate salts are hydrolyzed rarely by monogastric animals, because they lack the hydrolyzing phytases and thus excrete the majority of them. The β-propeller phytases (BPPs) hydrolyze these insoluble mineral-phytate salts efficiently. In this study, we cloned a novel BPP gene from a marine Pseudomonas sp. This Pseudomonas BPP gene (PsBPP) had low sequence identity with other known phytases and contained an extra internal repeat domain (residues 24-279) and a typical BPP domain (residues 280-634) at the C-terminus. Structurebased sequence alignment suggested that the N-terminal repeat domain did not possess the active-site residues, whereas the C-terminal BPP domain contained multiple calcium-binding sites, which provide a favorable electrostatic environment for substrate binding and catalytic activity. Thus, we overexpressed the BPP domain from Pseudomonas sp. to potentially hydrolyze insoluble mineral-phytate salts. Purified recombinant PsBPP required Ca(2+) or Fe(2+) for phytase activity, indicating that PsBPP hydrolyzes insoluble Fe(2+)-phytate or Ca2+-phytate salts. The optimal temperature and pH for the hydrolysis of Ca(2+)-phytate by PsBPP were 50°C and 6.0, respectively. Biochemical and kinetic studies clearly showed that PsBPP efficiently hydrolyzed Ca(2+)-phytate salts and yielded myo-inositol 2,4,6-trisphosphate and three phosphate groups as final products. Finally, we showed that PsBPP was highly effective for hydrolyzing rice bran with high phytate content. Taken together, our results suggest that PsBPP has great potential in the animal feed industry for reducing phytates.

  4. Whole genome sequences of a free-living Pseudomonas sp. strain ML96 isolated from a freshwater Maar Lake.

    PubMed

    Li, Xiuling; Blom, Jochen; Zeng, Yonghui

    2015-12-01

    A free living freshwater Pseudomonas strain ML96 was isolated from the Huguangyan Maar Lake in southern China. Genome sequencing of strain ML96 revealed a 4.7 Mb long draft genome consisting of 47 contigs with a G+C content of 64.8%. Its 16S and 23S rRNA gene sequences were 99.8% and 99.3% identical to those of its closest relative, Pseudomonas alcaligenes NBRC 14159, respectively. ML96's genome shared 73% orthologous CDS (3256/4457) with the genome of NBRC 14159. Comparative genomics analysis provide further insight into the diversity and evolution of aquatic Pseudomonas species, which may help enhance our understanding of this both environmentally and medically important group of bacteria.

  5. A Gene Cluster Encoding Steps in Conversion of Naphthalene to Gentisate in Pseudomonas sp. Strain U2

    PubMed Central

    Fuenmayor, Sergio L.; Wild, Mark; Boyes, Alastair L.; Williams, Peter A.

    1998-01-01

    Pseudomonas sp. strain U2 was isolated from oil-contaminated soil in Venezuela by selective enrichment on naphthalene as the sole carbon source. The genes for naphthalene dioxygenase were cloned from the plasmid DNA of strain U2 on an 8.3-kb BamHI fragment. The genes for the naphthalene dioxygenase genes nagAa (for ferredoxin reductase), nagAb (for ferredoxin), and nagAc and nagAd (for the large and small subunits of dioxygenase, respectively) were located by Southern hybridizations and by nucleotide sequencing. The genes for nagB (for naphthalene cis-dihydrodiol dehydrogenase) and nagF (for salicylaldehyde dehydrogenase) were inferred from subclones by their biochemical activities. Between nagAa and nagAb were two open reading frames, homologs of which have also been identified in similar locations in two nitrotoluene-using strains (J. V. Parales, A. Kumar, R. E. Parales, and D. T. Gibson, Gene 181:57–61, 1996; W.-C. Suen, B. Haigler, and J. C. Spain, J. Bacteriol. 178:4926–4934, 1996) and a naphthalene-using strain (G. J. Zylstra, E. Kim, and A. K. Goyal, Genet. Eng. 19:257–269, 1997). Recombinant Escherichia coli strains with plasmids carrying this region were able to convert salicylate to gentisate, which was identified by a combination of gas chromatography-mass spectrometry and nuclear magnetic resonance. The first open reading frame, designated nagG, encodes a protein with characteristics of a Rieske-type iron-sulfur center homologous to the large subunits of dihydroxylating dioxygenases, and the second open reading frame, designated nagH, encodes a protein with limited homology to the small subunits of the same dioxygenases. Cloned together in E. coli, nagG, nagH, and nagAb, were able to convert salicylate (2-hydroxybenzoate) into gentisate (2,5-dihydroxybenzoate) and therefore encode a salicylate 5-hydroxylase activity. Single-gene knockouts of nagG, nagH, and nagAb demonstrated their functional roles in the formation of gentisate. It is proposed

  6. Co-immobilization of Pseudomonas stutzeri YHA-13 and Alcaligenes sp. ZGED-12 with polyvinyl alcohol-alginate for removal of nitrogen and phosphorus from synthetic wastewater.

    PubMed

    Han, Yonghe; Zhang, Wenxian; Lu, Wenxian; Zhou, Zhihua; Zhuang, Zhigang; Li, Min

    2014-01-01

    Nitrogen (N) and phosphorus (P) are the two main factors causing water eutrophication. Immobilized micro-organisms have been widely studied in N and P removal. However, the effects of various immobilizing conditions on the removal efficiency of N and P using immobilized micro-organism beads (IMOBs) remain unclear. Polyvinyl alcohol (PVA) and alginate, as the two frequently immobilizing-used matrixes, were used for co-immobilizing Pseudomonas stutzeri YHA-13 and Alcaligenes sp. ZGED-12. PVA, alginate and CaCl₂contents, immobilization time and different wet biomass ratios of P. stutzeri to Alcaligenes sp. were conducted to elucidate their roles in and influences on the removal efficiency of N and P from synthetic wastewater. The application potential of IMOBs was estimated as well. Results showed that IMOBs prepared by cross-link of 4% PVA and 2-3% alginate with 5% CaCl₂and saturated boric acid solution for 10-15 min are the best ones in removal of N and P. Though IMOBs containing P. stutzeri and/or Alcaligenes sp. were capable of removal of the two nutrients, the highest removal efficiency was observed when the wet biomass ratio of P. stutzeri to Alcaligenes sp. was adjusted to 2:2. In addition, the IMOBs were of good ability to remove chemical oxygen demand (COD), NO(3)(-), NO(2)(-), NH(4)(+)- N, total nitrogen (TN) and total phosphorus (TP) from artificial wastewater. Of which, micro-organisms immobilized in matrixes were mainly responsible for NO(3)(-) and TP removal. Therefore, P. stutzeri YHA-13 and Alcaligenes sp. ZGED-12 are reliable bioresources to remove N and P from wastewater.

  7. Biogenic Strain of Silver and Selenium Nanoparticles by Pseudomonas fluorescens and Cladosporium sp. JAPSK3 Isolated from Coal Mine Samples and Their Antimicrobial Activity

    NASA Astrophysics Data System (ADS)

    Singh, Nidhi; Saha, Prasenjit; Rajkumar, Karthik; Abraham, Jayanthi

    2014-08-01

    Selenium and silver have unique properties and great potential in the field of physics, chemistry and biology. The bacterial strain Pseudomonas fluorescens was isolated by using Kings'B media and Cladosporium sp. was isolated by using potato dextrose agar for soil sample collected from Andhra Pradesh coal field of Singareni. Rapid formation of stable silver and selenium nanoparticles (AgNPs; SeNPs) were observed on exposure of the microbial culture with solution of silver nitrate and sodium selenite. The nanoparticles were characterized by UV-visible spectroscopy, X-ray diffraction (XRD) and atomic force microscopy (AFM). Further, the biologically synthesized nanoparticles were found to have efficient antimicrobial activity against pathogenic bacteria, thus implying significance of the present study in production of biomedical products. AgNPs synthesized by P. fluorescens showed more antimicrobial activity than Cladosporium sp. As the AgNPs are much smaller in size, they showed effective antimicrobial activity when compared to that of SeNPs which showed less effective antimicrobial activity in both P. fluorescens and Cladosporium sp. The microbes are capable of reducing both AgNPs and SeNPs. The biological synthesis of nanoparticles is useful when compared with other physical and chemical methods as they are eco-friendly.

  8. A coniferyl aldehyde dehydrogenase gene from Pseudomonas sp. strain HR199 enhances the conversion of coniferyl aldehyde by Saccharomyces cerevisiae.

    PubMed

    Adeboye, Peter Temitope; Olsson, Lisbeth; Bettiga, Maurizio

    2016-07-01

    The conversion of coniferyl aldehyde to cinnamic acids by Saccharomyces cerevisiae under aerobic growth conditions was previously observed. Bacteria such as Pseudomonas have been shown to harbor specialized enzymes for converting coniferyl aldehyde but no comparable enzymes have been identified in S. cerevisiae. CALDH from Pseudomonas was expressed in S. cerevisiae. An acetaldehyde dehydrogenase (Ald5) was also hypothesized to be actively involved in the conversion of coniferyl aldehyde under aerobic growth conditions in S. cerevisiae. In a second S. cerevisiae strain, the acetaldehyde dehydrogenase (ALD5) was deleted. A prototrophic control strain was also engineered. The engineered S. cerevisiae strains were cultivated in the presence of 1.1mM coniferyl aldehyde under aerobic condition in bioreactors. The results confirmed that expression of CALDH increased endogenous conversion of coniferyl aldehyde in S. cerevisiae and ALD5 is actively involved with the conversion of coniferyl aldehyde in S. cerevisiae.

  9. Gene Cloning, Nucleotide Sequencing, and Purification and Characterization of the Low-Specificity l-Threonine Aldolase from Pseudomonas sp. Strain NCIMB 10558

    PubMed Central

    Liu, Ji-Quan; Ito, Saeko; Dairi, Tohru; Itoh, Nobuya; Kataoka, Michihiko; Shimizu, Sakayu; Yamada, Hideaki

    1998-01-01

    A low-specificity l-threonine aldolase (l-TA) gene from Pseudomonas sp. strain NCIMB 10558 was cloned and sequenced. The gene contains an open reading frame consisting of 1,041 nucleotides corresponding to 346 amino acid residues. The gene was overexpressed in Escherichia coli cells, and the recombinant enzyme was purified and characterized. The enzyme, requiring pyridoxal 5′-phosphate as a coenzyme, is strictly l specific at the α position, whereas it cannot distinguish between threo and erythro forms at the β position. In addition to threonine, the enzyme also acts on various other l-β-hydroxy-α-amino acids, including l-β-3,4-dihydroxyphenylserine, l-β-3,4-methylenedioxyphenylserine, and l-β-phenylserine. The predicted amino acid sequence displayed less than 20% identity with those of low-specificity l-TA from Saccharomyces cerevisiae, l-allo-threonine aldolase from Aeromonas jandaei, and four relevant hypothetical proteins from other microorganisms. However, lysine 207 of low-specificity l-TA from Pseudomonas sp. strain NCIMB 10558 was found to be completely conserved in these proteins. Site-directed mutagenesis experiments showed that substitution of Lys207 with Ala or Arg resulted in a significant loss of enzyme activity, with the corresponding disappearance of the absorption maximum at 420 nm. Thus, Lys207 of the l-TA probably functions as an essential catalytic residue, forming an internal Schiff base with the pyridoxal 5′-phosphate of the enzyme to catalyze the reversible aldol reaction. PMID:9464392

  10. Mercury (II) removal by resistant bacterial isolates and mercuric (II) reductase activity in a new strain of Pseudomonas sp. B50A.

    PubMed

    Giovanella, Patricia; Cabral, Lucélia; Bento, Fátima Menezes; Gianello, Clesio; Camargo, Flávio Anastácio Oliveira

    2016-01-25

    This study aimed to isolate mercury resistant bacteria, determine the minimum inhibitory concentration for Hg, estimate mercury removal by selected isolates, explore the mer genes, and detect and characterize the activity of the enzyme mercuric (II) reductase produced by a new strain of Pseudomonas sp. B50A. The Hg removal capacity of the isolates was determined by incubating the isolates in Luria Bertani broth and the remaining mercury quantified by atomic absorption spectrophotometry. A PCR reaction was carried out to detect the merA gene and the mercury (II) reductase activity was determined in a spectrophotometer at 340 nm. Eight Gram-negative bacterial isolates were resistant to high mercury concentrations and capable of removing mercury, and of these, five were positive for the gene merA. The isolate Pseudomonas sp. B50A removed 86% of the mercury present in the culture medium and was chosen for further analysis of its enzyme activity. Mercuric (II) reductase activity was detected in the crude extract of this strain. This enzyme showed optimal activity at pH 8 and at temperatures between 37 °C and 45 °C. The ions NH4(+), Ba(2+), Sn(2+), Ni(2+) and Cd(2+) neither inhibited nor stimulated the enzyme activity but it decreased in the presence of the ions Ca(2+), Cu(+) and K(+). The isolate and the enzyme detected were effective in reducing Hg(II) to Hg(0), showing the potential to develop bioremediation technologies and processes to clean-up the environment and waste contaminated with mercury.

  11. Identification of an additional ferric-siderophore uptake gene clustered with receptor, biosynthesis, and fur-like regulatory genes in fluorescent Pseudomonas sp. strain M114.

    PubMed Central

    O'Sullivan, D J; Morris, J; O'Gara, F

    1990-01-01

    Five cosmid clones with insert sizes averaging 22.6 kilobases (kb) were isolated after complementation of 22 Tn5-induced Sid- mutants of Pseudomonas sp. strain M114. One of these plasmids (pMS639) was also shown to encode ferric-siderophore receptor and dissociation functions. The receptor gene was located on this plasmid since introduction of the plasmid into three wild-type fluorescent pseudomonads enabled them to utilize the ferric-siderophore from strain M114. The presence of an extra iron-regulated protein in the outer membrane profile of one of these strains was detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. A ferric-siderophore dissociation gene was attributed to pMS639 since it complemented the ferric-siderophore uptake mutation in strain M114FR2. This mutant was not defective in the outer membrane receptor for ferric-siderophore but apparently accumulated ferric-siderophore internally. Since ferric-citrate alleviated the iron stress of the mutant, there was no defect in iron metabolism subsequent to release of iron from the ferric-siderophore complex. Consequently, this mutant was defective in ferric-siderophore dissociation. A fur-like regulatory gene also present on pMS639 was subcloned to a 7.0-kb BglII insert of pCUP5 and was located approximately 7.3 kb from the receptor region. These results established that the 27.2-kb insert of pMS639 encoded at least two siderophore biosynthesis genes, ferric-siderophore receptor and dissociation genes, and a fur-like regulatory gene from the biocontrol fluorescent Pseudomonas sp. strain M114. Images PMID:2143887

  12. Characterization of Pb(2+) biosorption by psychrotrophic strain Pseudomonas sp. I3 isolated from permafrost soil of Mohe wetland in Northeast China.

    PubMed

    Li, Dandan; Xu, Xingjian; Yu, Hongwen; Han, Xuerong

    2017-03-08

    Due to the long and severe winter in Northeast China, wastewater containing lead (Pb) is treated inefficiently, resulting in irregular disposal. In order to solve this problem, a Pb-resistant psychrotrophic bacterium, Pseudomonas sp. I3, was isolated from permafrost soil of Mohe wetland and served as biosorbent for Pb(2+) removal under 15 °C. The minimum inhibitory concentration of strain I3 for Pb(2+) was 7.5 mM, which was higher than that of Escherichia coli DH5α (1.5 mM). However, acid digestion results showed that these two bacteria had a comparable biosorption capacity for Pb(2+), suggesting no direct relationship between biosorption ability of bacteria and their metal-resistance. Acid digestion results also proved that intracellular Pb accumulation was mainly contributed to the distinct performance between living and non-living biosorbents, which was further confirmed by the analyses of TEM-EDS. Results of FTIR revealed that functional groups including CH2, CO, CN, NH, COO and SO3 were participated in the biosorption process of the tested biosorbents no matter bacteria were living or not. The effects of environmental factors including pH, temperature, biomass dose, operation time and initial Pb(2+) concentration were investigated through a batch of biosorption experiments. The equilibrium data for living and non-living biosorbent were well fitted to Langmuir model with their maximum Pb(2+) biosorption capacities of 49.48 and 42.37 mg/g, respectively. The kinetic data for each biosorbent were well described by pseudo-second order kinetic model. Overall, Pseudomonas sp. I3 seemed to be an effective biosorbent for cleansing Pb(2+) from contaminated wastewater at low temperature.

  13. Forward genetic in planta screen for identification of plant-protective traits of Sphingomonas sp. strain Fr1 against Pseudomonas syringae DC3000.

    PubMed

    Vogel, Christine; Innerebner, Gerd; Zingg, Judith; Guder, Jan; Vorholt, Julia A

    2012-08-01

    Sphingomonas sp. strain Fr1 has recently been shown to protect Arabidopsis thaliana against the bacterial leaf pathogen Pseudomonas syringae DC3000. Here, we describe a forward genetic in planta screen to identify genes in Sphingomonas sp. Fr1 necessary for this effect. About 5,000 Sphingomonas sp. Fr1 mini-Tn5 mutants were assayed for a defect in plant protection against a luxCDABE-tagged P. syringae DC3000 derivative in a space-saving 24-well plate system. The bioluminescence of the pathogen was used as the indicator of pathogen proliferation and allowed for the identification of Sphingomonas sp. Fr1 mutants that had lost the ability to restrict pathogen growth before disease symptoms were visible. Potential candidates were validated using the same miniaturized experimental system. Of these mutants, 10 were confirmed as plant protection defective yet colonization competent. The mutants were subsequently evaluated in a previously described standard microbox system, and plants showed enhanced disease phenotypes after pathogen infection relative to those inoculated with the parental strain as a control. However, the disease severities were lower than those observed for control plants that were grown axenically prior to pathogen challenge, which suggests that several traits may contribute to plant protection. Transposon insertion sites of validated mutants with defects in plant protection were determined and mapped to 7 distinct genomic regions. In conclusion, the established screening protocol allowed us to identify mutations that affect plant protection, and it opens the possibility to uncover traits important for in planta microbe-microbe interactions.

  14. Forward Genetic In Planta Screen for Identification of Plant-Protective Traits of Sphingomonas sp. Strain Fr1 against Pseudomonas syringae DC3000

    PubMed Central

    Vogel, Christine; Innerebner, Gerd; Zingg, Judith; Guder, Jan

    2012-01-01

    Sphingomonas sp. strain Fr1 has recently been shown to protect Arabidopsis thaliana against the bacterial leaf pathogen Pseudomonas syringae DC3000. Here, we describe a forward genetic in planta screen to identify genes in Sphingomonas sp. Fr1 necessary for this effect. About 5,000 Sphingomonas sp. Fr1 mini-Tn5 mutants were assayed for a defect in plant protection against a luxCDABE-tagged P. syringae DC3000 derivative in a space-saving 24-well plate system. The bioluminescence of the pathogen was used as the indicator of pathogen proliferation and allowed for the identification of Sphingomonas sp. Fr1 mutants that had lost the ability to restrict pathogen growth before disease symptoms were visible. Potential candidates were validated using the same miniaturized experimental system. Of these mutants, 10 were confirmed as plant protection defective yet colonization competent. The mutants were subsequently evaluated in a previously described standard microbox system, and plants showed enhanced disease phenotypes after pathogen infection relative to those inoculated with the parental strain as a control. However, the disease severities were lower than those observed for control plants that were grown axenically prior to pathogen challenge, which suggests that several traits may contribute to plant protection. Transposon insertion sites of validated mutants with defects in plant protection were determined and mapped to 7 distinct genomic regions. In conclusion, the established screening protocol allowed us to identify mutations that affect plant protection, and it opens the possibility to uncover traits important for in planta microbe-microbe interactions. PMID:22660707

  15. When Genome-Based Approach Meets the “Old but Good”: Revealing Genes Involved in the Antibacterial Activity of Pseudomonas sp. P482 against Soft Rot Pathogens

    PubMed Central

    Krzyżanowska, Dorota M.; Ossowicki, Adam; Rajewska, Magdalena; Maciąg, Tomasz; Jabłońska, Magdalena; Obuchowski, Michał; Heeb, Stephan; Jafra, Sylwia

    2016-01-01

    Dickeya solani and Pectobacterium carotovorum subsp. brasiliense are recently established species of bacterial plant pathogens causing black leg and soft rot of many vegetables and ornamental plants. Pseudomonas sp. strain P482 inhibits the growth of these pathogens, a desired trait considering the limited measures to combat these diseases. In this study, we determined the genetic background of the antibacterial activity of P482, and established the phylogenetic position of this strain. Pseudomonas sp. P482 was classified as Pseudomonas donghuensis. Genome mining revealed that the P482 genome does not contain genes determining the synthesis of known antimicrobials. However, the ClusterFinder algorithm, designed to detect atypical or novel classes of secondary metabolite gene clusters, predicted 18 such clusters in the genome. Screening of a Tn5 mutant library yielded an antimicrobial negative transposon mutant. The transposon insertion was located in a gene encoding an HpcH/HpaI aldolase/citrate lyase family protein. This gene is located in a hypothetical cluster predicted by the ClusterFinder, together with the downstream homologs of four nfs genes, that confer production of a non-fluorescent siderophore by P. donghuensis HYST. Site-directed inactivation of the HpcH/HpaI aldolase gene, the adjacent short chain dehydrogenase gene, as well as a homolog of an essential nfs cluster gene, all abolished the antimicrobial activity of the P482, suggesting their involvement in a common biosynthesis pathway. However, none of the mutants showed a decreased siderophore yield, neither was the antimicrobial activity of the wild type P482 compromised by high iron bioavailability. A genomic region comprising the nfs cluster and three upstream genes is involved in the antibacterial activity of P. donghuensis P482 against D. solani and P. carotovorum subsp. brasiliense. The genes studied are unique to the two known P. donghuensis strains. This study illustrates that mining of

  16. Application of Glomus sp. and Pseudomonas diminuta Reduce the Use of Chemical Fertilizers in Production of Potato Grown on Different Soil Types

    NASA Astrophysics Data System (ADS)

    Nurbaity, A.; Sofyan, E. T.; Hamdani, J. S.

    2016-08-01

    The use of high chemical fertilizer rates in potato production has been applied on the farm in Indonesia. Application of biofertilizer consists of arbuscular mycorrhizal fungi has been tested to reduce the use of NPK rates in production of potato and to determine whether different soil types will have different response to this biofertilizer. A greenhouse experiment was conducted using mixtures of spores of Glomus sp. and inoculant of mycorrhizal helper bacteria Pseudomonas diminuta, applied at different rates of NPK fertilizer (0, 25, 50, 75 and 100% of recommended rates) and different soil types (Andisols and Inceptisols). Results of experiment showed that application of Glomus sp. and P. diminuta reduced the use of NPK up to 50%, where the growth (plant height and tuber number), N,P,K uptake and tuber yields of potato had similar effect to the highest recommendation rate of NPK fertilizer. Inceptisols in general had better response to the biofertiliser compared to Andisols. Findings from this experiment confirmed the evidences that biofertilizer could reduce the use of chemical fertilizer, and the widely distributed soil in Indonesia such as Inceptisols, is potential to be used as a medium for potato production.

  17. Metabolic engineering of Pseudomonas sp. strain VLB120 as platform biocatalyst for the production of isobutyric acid and other secondary metabolites

    PubMed Central

    2014-01-01

    Background Over the recent years the production of Ehrlich pathway derived chemicals was shown in a variety of hosts such as Escherichia coli, Corynebacterium glutamicum, and yeast. Exemplarily the production of isobutyric acid was demonstrated in Escherichia coli with remarkable titers and yields. However, these examples suffer from byproduct formation due to the fermentative growth mode of the respective organism. We aim at establishing a new aerobic, chassis for the synthesis of isobutyric acid and other interesting metabolites using Pseudomonas sp. strain VLB120, an obligate aerobe organism, as host strain. Results The overexpression of kivd, coding for a 2-ketoacid decarboxylase from Lactococcus lactis in Ps. sp. strain VLB120 enabled for the production of isobutyric acid and isobutanol via the valine synthesis route (Ehrlich pathway). This indicates the existence of chromosomally encoded alcohol and aldehyde dehydrogenases catalyzing the reduction and oxidation of isobutyraldehyde. In addition we showed that the strain possesses a complete pathway for isobutyric acid metabolization, channeling the compound via isobutyryl-CoA into valine degradation. Three key issues were addressed to allow and optimize isobutyric acid synthesis: i) minimizing isobutyric acid degradation by host intrinsic enzymes, ii) construction of suitable expression systems and iii) streamlining of central carbon metabolism finally leading to production of up to 26.8 ± 1.5 mM isobutyric acid with a carbon yield of 0.12 ± 0.01 g gglc-1. Conclusion The combination of an increased flux towards isobutyric acid using a tailor-made expression system and the prevention of precursor and product degradation allowed efficient production of isobutyric acid in Ps. sp. strain VLB120. This will be the basis for the development of a continuous reaction process for this bulk chemicals. PMID:24397404

  18. Sequence analysis and structure prediction of type II Pseudomonas sp. USM 4–55 PHA synthase and an insight into its catalytic mechanism

    PubMed Central

    Wahab, Habibah A; Ahmad Khairudin, Nurul Bahiyah; Samian, Mohd Razip; Najimudin, Nazalan

    2006-01-01

    Background Polyhydroxyalkanoates (PHA), are biodegradable polyesters derived from many microorganisms such as the pseudomonads. These polyesters are in great demand especially in the packaging industries, the medical line as well as the paint industries. The enzyme responsible in catalyzing the formation of PHA is PHA synthase. Due to the limited structural information, its functional properties including catalysis are lacking. Therefore, this study seeks to investigate the structural properties as well as its catalytic mechanism by predicting the three-dimensional (3D) model of the Type II Pseudomonas sp. USM 4–55 PHA synthase 1 (PhaC1P.sp USM 4–55). Results Sequence analysis demonstrated that PhaC1P.sp USM 4–55 lacked similarity with all known structures in databases. PSI-BLAST and HMM Superfamily analyses demonstrated that this enzyme belongs to the alpha/beta hydrolase fold family. Threading approach revealed that the most suitable template to use was the human gastric lipase (PDB ID: 1HLG). The superimposition of the predicted PhaC1P.sp USM 4–55 model with 1HLG covering 86.2% of the backbone atoms showed an RMSD of 1.15 Å. The catalytic residues comprising of Cys296, Asp451 and His479 were found to be conserved and located adjacent to each other. In addition to this, an extension to the catalytic mechanism was also proposed whereby two tetrahedral intermediates were believed to form during the PHA biosynthesis. These transition state intermediates were further postulated to be stabilized by the formation of oxyanion holes. Based on the sequence analysis and the deduced model, Ser297 was postulated to contribute to the formation of the oxyanion hole. Conclusion The 3D model of the core region of PhaC1P.sp USM 4–55 from residue 267 to residue 484 was developed using computational techniques and the locations of the catalytic residues were identified. Results from this study for the first time highlighted Ser297 potentially playing an important role in

  19. Colonization of potato rhizosphere by GFP-tagged Bacillus subtilis MB73/2, Pseudomonas sp. P482 and Ochrobactrum sp. A44 shown on large sections of roots using enrichment sample preparation and confocal laser scanning microscopy.

    PubMed

    Krzyzanowska, Dorota; Obuchowski, Michal; Bikowski, Mariusz; Rychlowski, Michal; Jafra, Sylwia

    2012-12-18

    The ability to colonize the host plants' rhizospheres is a crucial feature to study in the case of Plant Growth Promoting Rhizobacteria (PGPRs) with potential agricultural applications. In this work, we have created GFP-tagged derivatives of three candidate PGPRs: Bacillus subtilis MB73/2, Pseudomonas sp. P482 and Ochrobactrum sp. A44. The presence of these strains in the rhizosphere of soil-grown potato (Solanum tuberosum L.) was detected with a classical fluorescence microscope and a confocal laser scanning microscope (CLSM). In this work, we have used a broad-field-of-view CLMS device, dedicated to in vivo analysis of macroscopic objects, equipped with an automated optical zoom system and tunable excitation and detection spectra. We show that features of this type of CLSM microscopes make them particularly well suited to study root colonization by microorganisms. To facilitate the detection of small and scattered bacterial populations, we have developed a fast and user-friendly enrichment method for root sample preparation. The described method, thanks to the in situ formation of mini-colonies, enables visualization of bacterial colonization sites on large root fragments. This approach can be easily modified to study colonization patterns of other fluorescently tagged strains. Additionally, dilution plating of the root extracts was performed to estimate the cell number of MB73/2, P482 and A44 in the rhizosphere of the inoculated plants.

  20. A β-Alanine Catabolism Pathway Containing a Highly Promiscuous ω-Transaminase in the 12-Aminododecanate-Degrading Pseudomonas sp. Strain AAC

    PubMed Central

    Wilding, Matthew; Peat, Thomas S.; Newman, Janet

    2016-01-01

    ABSTRACT We previously isolated the transaminase KES23458 from Pseudomonas sp. strain AAC as a promising biocatalyst for the production of 12-aminododecanoic acid, a constituent building block of nylon-12. Here, we report the subsequent characterization of this transaminase. It exhibits activity with a broad substrate range which includes α-, β-, and ω-amino acids, as well as α,ω-diamines and a number of other industrially relevant compounds. It is therefore a prospective candidate for the biosynthesis of a range of polyamide monomers. The crystal structure of KES23458 revealed that the protein forms a dimer containing a large active site pocket and unusual phosphorylated histidine residues. To infer the physiological role of the transaminase, we expressed, purified, and characterized a dehydrogenase from the same operon, KES23460. Unlike the transaminase, the dehydrogenase was shown to be quite selective, catalyzing the oxidation of malonic acid semialdehyde, formed from β-alanine transamination via KES23458. In keeping with previous reports, the dehydrogenase was shown to catalyze both a coenzyme A (CoA)-dependent reaction to form acetyl-CoA and a significantly slower CoA-independent reaction to form acetate. These findings support the original functional assignment of KES23458 as a β-alanine transaminase. However, a seemingly well-adapted active site and promiscuity toward unnatural compounds, such as 12-aminododecanoic acid, suggest that this enzyme could perform multiple functions for Pseudomonas sp. strain AAC. IMPORTANCE We describe the characterization of an industrially relevant transaminase able to metabolize 12-aminododecanoic acid, a constituent building block of the widely used polymer nylon-12, and we report the biochemical and structural characterization of the transaminase protein. A physiological role for this highly promiscuous enzyme is proposed based on the characterization of a related gene from the host organism. Molecular dynamics

  1. The induction of Ethylene response factor 3 (ERF3) in potato as a result of co-inoculation with Pseudomonas sp. R41805 and Rhizophagus irregularis MUCL 41833 – a possible role in plant defense

    PubMed Central

    Velivelli, Siva LS; Lojan, Paul; Cranenbrouck, Sylvie; de Boulois, Hervé Dupré; Suarez, Juan Pablo; Declerck, Stéphane; Franco, Javier; Prestwich, Barbara Doyle

    2015-01-01

    Colonization of plant rhizosphere/roots by beneficial microorganisms (e.g. plant growth promoting rhizobacteria – PGPR, arbuscular mycorrhizal fungi – AMF) confers broad-spectrum resistance to virulent pathogens and is known as induced systemic resistance (ISR) and mycorrhizal-induced resistance (MIR). ISR or MIR, an indirect mechanism for biocontrol, involves complex signaling networks that are regulated by several plant hormones, the most important of which are salicylic acid (SA), jasmonic acid (JA) and ethylene (ET). In the present study, we investigated if inoculation of potato plantlets with an AMF (Rhizophagus irregularis MUCL 41833) and a PGPR (Pseudomonas sp R41805) either alone or in combination, could elicit host defense response genes in the presence or absence of Rhizoctonia Solani EC-1, a major potato pathogen. RT-qPCR revealed the significant expression of ethylene response factor 3 (EFR3) in mycorrhized potato plantlets inoculated with Pseudomonas sp R41805 and also in mycorrhized potato plantlets inoculated with Pseudomonas sp R41805 and challenged with R. solani. The significance of ethylene response factors (ERFs) in pathogen defense has been well documented in the literature. The results of the present study suggest that the dual inoculation of potato with PGPR and AMF may play a part in the activation of plant systemic defense systems via ERF3. PMID:25723847

  2. Combined removal of a BTEX, TCE, and cis-DCE mixture using Pseudomonas sp. immobilized on scrap tyres.

    PubMed

    Lu, Qihong; de Toledo, Renata Alves; Xie, Fei; Li, Junhui; Shim, Hojae

    2015-09-01

    The simultaneous aerobic removal of a mixture of benzene, toluene, ethylbenzene, and o,m,p-xylene (BTEX); cis-dichloroethylene (cis-DCE); and trichloroethylene (TCE) from the artificially contaminated water using an indigenous bacterial isolate identified as Pseudomonas plecoglossicida immobilized on waste scrap tyres was investigated. Suspended and immobilized conditions were compared for the removal of these volatile organic compounds. For the immobilized system, toluene, benzene, and ethylbenzene were completely removed, while the highest removal efficiencies of 99.0 ± 0.1, 96.8 ± 0.3, 73.6 ± 2.5, and 61.6 ± 0.9% were obtained for o-xylene, m,p-xylene, TCE, and cis-DCE, respectively. The sorption kinetics of contaminants towards tyre surface was also evaluated, and the sorption capacity generally followed the order of toluene > benzene > m,p-xylene > o-xylene > ethylbenzene > TCE > cis-DCE. Scrap tyres showed a good capability for the simultaneous sorption and bioremoval of BTEX/cis-DCE/TCE mixture, implying a promising waste material for the removal of contaminant mixture from industrial wastewater or contaminated groundwater.

  3. Degradation of 2,4-dinitroanisole (DNAN) by metabolic cooperative activity of Pseudomonas sp. strain FK357and Rhodococcus imtechensis strain RKJ300.

    PubMed

    Khan, Fazlurrahman; Pal, Deepika; Ghosh, Anuradha; Cameotra, Swaranjit Singh

    2013-11-01

    2,4-Dinitroanisole (DNAN) is an insensitive explosive ingredient used by many defense agencies as a replacement for 2,4,6-trinitrotoluene. Although the biotransformation of DNAN under anaerobic condition has been reported, aerobic microbial degradation pathway has not been elucidated. An n-methyl-4-nitroaniline degrading bacterium Pseudomonas sp. strain FK357 transformed DNAN into 2,4-dinitrophenol (2,4-DNP) as an end product. Interestingly, when strain FK357 was co-cultured with a 2,4-DNP degrading Rhodococcus imtechensis strain RKJ300, complete and high rate of DNAN degradation was observed with no accumulation of intermediates. Enzyme assay using cell extracts of strain FK357 demonstrated that O-demethylation reaction is the first step of DNAN degradation with formation of 2,4-DNP and formaldehyde as intermediates. Subsequently, 2,4-DNP was degraded by strain RKJ300 via the formation of hydride-Meisenheimer complex. The present study clearly demonstrates that complete degradation of DNAN occurs as a result of the metabolic cooperative activity of two members within a bacterial consortium.

  4. Solid-state /sup 13/C nuclear magnetic resonance spectroscopy of simultaneously metabolized acetate and phenol in a soil Pseudomonas sp

    SciTech Connect

    Heiman, A.S.; Copper, W.T.

    1987-01-01

    An investigation was made of the concentration-dependent primary and secondary substrate relationships in the simultaneous metabolism of the ubiquitous pollutant phenol and the naturally occurring substrate acetate by a Pseudomonas sp. soil isolate capable of utilizing either substance as a sole source of carbon and energy. In addition to conventional analytical techniques, solid-state /sup 13/C nuclear magnetic resonance spectroscopy was used to follow the cellular distribution of (1-/sup 13/C)acetate in the presence of unlabeled phenol. These results suggest that, when phenol is present as the primary substrate, acetate is preferentially shuttled into fatty acyl chain synthesis, whereas phenol carbon is funnelled into the tricarboxylic acid cycle. Thus, simultaneous use of a xenobiotic compound and a natural substrate apparently does occur, and the relative concentrations of the two substrates do influence the rate and manner in which the compounds are utilized. These results also demonstrate the unique advantage of using solid-state nuclear magnetic resonance techniques combined with /sup 13/C labeling of specific sites in substrates when doing microbial degradation studies. In this work, the entire cellular biomass was examined directly without extensive extraction, fractionation, or isolation of subcellular units; thus, there is no uncertainty about chemical alteration of substrate metabolites as a result of these often harsh treatments.

  5. Reduction of oxidative stress by bioaugmented strain Pseudomonas sp. HF-1 and selection of potential biomarkers in sequencing batch reactor treating tobacco wastewater.

    PubMed

    Shao, Tiejuan; Yang, Guiqin; Wang, Meizhen; Lu, Zhenmei; Min, Hang; Zhao, Long

    2010-08-01

    Oxidative stress induced by toxic pollutants is generally responsible for the poor performance of many sequencing batch reactors (SBRs) treating organic wastewater. In this study, the oxidative stress in two SBR systems that dealt with tobacco wastewater was monitored by measuring four popular biomarkers (superoxide dismutase, SOD; catalase, CAT; glutathione, GSH; and malondialdehyde, MDA). In the non-BA (non-bio-augmented) system, more intense oxidative stress was induced by a higher concentration of nicotine in tobacco wastewater, and excessive oxidative stress was induced by 250 mg/l of nicotine at the final stage. However, when a nicotine-degrading bacterial strain Pseudomonas sp. HF-1 was added to the BA (bio-augmented) system, the oxidative stress was significantly reduced compared to the non-BA system (p < 0.01).These results suggested that the oxidative stress was mainly induced by nicotine in the SBR treatment of tobacco wastewater, and that bioaugmentation with strain HF-1 would be a potential strategy to reduce the oxidative stress and thereby improve the performance in SBRs. Additionally, the positive correlation between the nicotine content and CAT, GSH and MDA activity in both systems implied that these parameters can be used as biomarkers for reflecting the performance of SBR treatment of tobacco wastewater, and in monitoring nicotine environmental pollution.

  6. Purification of low-concentration phenazine-1-carboxylic acid from fermentation broth of Pseudomonas sp. M18 via free flow electrophoresis with gratis gravity.

    PubMed

    Shao, Jing; Fan, Liu-Yin; Zhang, Wei; Guo, Chen-Gang; Li, Si; Xu, Yu-Quan; Cao, Cheng-Xi

    2010-10-01

    The low-concentration phenazine-1-carboxylic acid (PCA) ( = 0.3 mM) extracted from fermentation broth of Pseudomonas sp. M18 was selected to be purified with a newly facile free flow electrophoresis (FFE) device with gratis gravity. Three factors of pH value and concentration of background buffer, and the cooling circle of FFE device were investigated for the purification of PCA in the FFE device. It was found that the pH value and concentration of background buffer had mild influences on the separation of PCA whether with cooling circle or not. However, the cooling circle had a much greater impact on the separation of PCA. The controlling of the band zone of PCA in FFE chamber would be difficult if without cooling circle, while the controlling would become easy if with cooling circle. Under the optimal conditions (10 mM pH 5.5 phosphate as background buffer, 30 mM pH 5.5 phosphate buffer as electrode solution, 5.46 mL/min background flux, 10 min residence time of injected sample, and 500 V), PCA could be continuously prepared from its impurities with relative high purity. The flux of sample injection was 115 μL/min, viz. 7 mL sample throughput per hour, and the recovery was up to 85%. All of the experiments indicated that the FFE technique was a good alternative tool for the study on natural biological control agents.

  7. Identification of the bphA4 gene encoding ferredoxin reductase involved in biphenyl and polychlorinated biphenyl degradation in Pseudomonas sp. strain KKS102.

    PubMed Central

    Kikuchi, Y; Nagata, Y; Hinata, M; Kimbara, K; Fukuda, M; Yano, K; Takagi, M

    1994-01-01

    The nucleotide sequence of the downstream region of the bph operon from Pseudomonas sp. strain KKS102 was determined. Two open reading frames (ORF1 and ORF2) were found in this region, and the deduced amino acid sequence of ORF2 showed homology with the sequences of four ferredoxin reductases of dioxygenase systems. When this region was inserted just upstream of the bph operon, which does not contain a gene encoding ferredoxin reductase, biphenyl dioxygenase activity was detected. The 24- and 44-kDa polypeptides predicted from the two open reading frames were identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Crude extract which contained the products of ORF2 and bphA1A2A3 showed cytochrome c reduction activity. These data clearly suggest that ORF2 encodes ferredoxin reductase. The deduced amino acid sequence of ORF1 does not show significant homology with the sequences of any other proteins in the SWISS-PROT data bank, and the function of ORF1 is unknown. Images PMID:8132464

  8. Crystal structure of the γ-hydroxymuconic semialdehyde dehydrogenase from Pseudomonas sp. strainWBC-3, a key enzyme involved in para-Nitrophenol degradation

    PubMed Central

    2013-01-01

    Background para-Nitrophenol (PNP) is a highly toxic compound with threats to mammalian health. The pnpE-encoded γ-hydroxymuconic semialdehyde dehydrogenase catalyzes the reduction of γ-hydroxymuconic semialdehyde to maleylacetate in Pseudomonas sp. strain WBC-3, playing a key role in the catabolism of PNP to Krebs cycle intermediates. However, the catalyzing mechanism by PnpE has not been well understood. Results Here we report the crystal structures of the apo and NAD bound PnpE. In the PnpE-NAD complex structure, NAD is situated in a cleft of PnpE. The cofactor binding site is composed of two pockets. The adenosine and the first ribose group of NAD bind in one pocket and the nicotinamide ring in the other. Conclusions Six amino acids have interactions with the cofactor. They are C281, E247, Q210, W148, I146 and K172. Highly conserved residues C281 and E247 were identified to be critical for its catalytic activity. In addition, flexible docking studies of the enzyme-substrate system were performed to predict the interactions between PnpE and its substrate γ-hydroxymuconic semialdehyde. Amino acids that interact extensively with the substrate and stabilize the substrate in an orientation suitable for enzyme catalysis were identified. The importance of these residues for catalytic activity was confirmed by the relevant site-directed mutagenesis and their biochemical characterization. PMID:24252642

  9. Evaluation and elimination of inhibitory effects of salts and heavy metal ions on biodegradation of Congo red by Pseudomonas sp. mutant.

    PubMed

    Gopinath, Kannappan Panchamoorthy; Kathiravan, Mathur Natarajan; Srinivasan, Raman; Sankaranarayanan, Subramanian

    2011-02-01

    In this study, it was attempted to evaluate the influences and also recommended some elimination methods for inhibitory effects offered by salts and heavy metal ions. Congo red dye solution treated with mutant Pseudomonas sp. was taken as a model system for study. The salts used in this study are NaCl, CaCl(2) and MgSO(4)· 7H(2)O. Though the growth was inhibited at concentrations above 4 g/l, toleration was achieved by acclimatization process. In case of heavy metal ions, Cr (VI) showed low inhibition up to 500 mg/l of concentration, compared to Zn (II) and Cu (II). It was due to the presence of chromium reductase enzyme which was confirmed by SDS-PAGE. Zn (II) and Cu (II) ion inhibitions were eliminated by chelation with EDTA. The critical ion concentrations obtained as per Han-Levenspiel model for Cr (VI), Zn (II) and Cu (II) were 0.8958, 0.3028 and 0.204 g/l respectively.

  10. Cloning and expression of ophB gene encoding organophosphorus hydrolase from endophytic Pseudomonas sp. BF1-3 degrades organophosphorus pesticide chlorpyrifos.

    PubMed

    Barman, Dhirendra Nath; Haque, Md Azizul; Islam, Shah Md Asraful; Yun, Han Dae; Kim, Min Keun

    2014-10-01

    Chlorpyrifos is an organophosphate pesticide that has adverse effect on animals and plants. We isolated endophytic bacterial strain, Pseudomonas sp. BF1-3, from balloon flower root which can hydrolyze chlorpyrifos. A gene (ophB) encoding a protein involved in chlorpyrifos degradation from this strain was cloned into Escherichia coli DH5α for confirming enzyme activity. After sequencing, total 1024bp nucleotide sequences were found in the open reading frame of ophB. The chlorpyrifos degradation patterns by E. coli DH5α (ophB) were observed. During incubation in minimal salt (M9) medium supplemented with chlorpyrifos (100mgL(-1)), the E. coli DH5α harboring ophB degraded about 97% initial chlorpyrifos (100mgL(-1)) and accumulated 86mgL(-1) 3,5,6-trichloro-2-pyridinol (TCP) within 9 days. In addition, optical density (OD) of E. coli DH5α (ophB) culture at 600nm was increased from 0.172 to 1.118 within 2 days of inoculation in the chlorpyrifos supplemented M9 medium. The estimated molecular weight of purified OphB protein was determined to be 31.4kDa by SDS-PAGE. The OphB enzyme was most active at pH 8 and an optimal temperature around 35°C. These results indicate that endophytic bacteria are supposed to be useful for biological control of environments contaminated with pesticides.

  11. Isolation of a selenite-reducing and cadmium-resistant bacterium Pseudomonas sp. strain RB for microbial synthesis of CdSe nanoparticles.

    PubMed

    Ayano, Hiroyuki; Miyake, Masaki; Terasawa, Kanako; Kuroda, Masashi; Soda, Satoshi; Sakaguchi, Toshifumi; Ike, Michihiko

    2014-05-01

    Bacteria capable of synthesizing CdSe from selenite and cadmium ion were enriched from a soil sample. After repeated transfer of the soil-derived bacterial cultures to a new medium containing selenite and cadmium ion 42 times (during 360 days), an enrichment culture that can simultaneously remove selenite and cadmium ion (1 mM each) from the liquid phase was obtained. The culture's color became reddish-brown, indicating CdSe nanoparticle production, as confirmed by energy-dispersive x-ray spectra (EDS). As a result of isolation operations, the bacterium that was the most responsible for synthesizing CdSe, named Pseudomonas sp. RB, was obtained. Transmission electron microscopy and EDS revealed that this strain accumulated nanoparticles (10-20 nm) consisting of selenium and cadmium inside and on the cells when cultivated in the same medium for the enrichment culture. This report is the first describing isolation of a selenite-reducing and cadmium-resistant bacterium. It is useful for CdSe nanoparticle synthesis in the simple one-vessel operation.

  12. Functional characterization of a 28-kb catabolic island from Pseudomonas sp. M1 involved in biotransformation of β-myrcene and related plant-derived volatiles.

    PubMed

    Soares-Castro, Pedro; Montenegro-Silva, Pedro; Heipieper, Hermann J; Santos, Pedro M

    2017-02-17

    Pseudomonas sp. M1 is able to mineralize highly hydrophobic and recalcitrant compounds such as benzene, phenol and their methylated/halogenated derivatives, as well as the backbone of several monoterpenes. The ability to use such spectrum of compounds as sole carbon source is, most probably, associated with a genetic background evolved under different environmental constraints. The outstanding performance of M1 strain regarding β-myrcene catabolism was elucidated in this work, with focus on the biocatalytical potential of β-myrcene-associated core-code, comprised in a 28-kb genomic island (GI), predicted to be organized in 8 transcriptional units.Functional characterization of this locus with promoter-probes and analytical approaches validated the genetic organization predicted in silico and associated the β-myrcene-induced promoter activity to the production of β-myrcene derivatives. Notably, by using a whole-genome mutagenesis strategy, different genotypes of the 28-kb GI were generated, resulting in the identification of a novel putative β-myrcene hydroxylase, responsible for the initial oxidation of β-myrcene into myrcen-8-ol, and a sensor-like regulatory protein, whose inactivation abolished the myr+ trait of M1 cells.Moreover, it was demonstrated that the range of monoterpene substrates of M1 enzymatic repertoire, besides β-myrcene, also includes other acyclic (e.g. β-linalool) and cyclic molecules (e.g. R-(+)-limonene and (-)-β-pinene). Our findings are the cornerstone for following metabolic engineering approaches and hint a major role of the 28-kb GI in the biotransformation of a broad monoterpene-backbone spectrum for its future biotechnological applications.Importance Information regarding microbial systems able to biotransformation monoterpenes, especially β-myrcene, is limited and focused mainly in non-systematic metabolite identification. Full and detailed knowledge at the genetic, protein, metabolite and regulatory level is essential in

  13. Purification and characterization of benzoate-coenzyme A ligase and 2-aminobenzoate-coenzyme A ligases from a denitrifying Pseudomonas sp.

    PubMed Central

    Altenschmidt, U; Oswald, B; Fuchs, G

    1991-01-01

    The enzymes catalyzing the formation of coenzyme A (CoA) thioesters of benzoate and 2-aminobenzoate were studied in a denitrifying Pseudomonas sp. anaerobically grown with these aromatic acids and nitrate as sole carbon and energy sources. Three different rather specific aromatic acyl-CoA ligases, E1, E2, and E3, were found which catalyze the formation of CoA thioesters of benzoate, fluorobenzoates, and 2-aminobenzoate. ATP is cleaved into AMP and pyrophosphate. The enzymes were purified, their N-terminal amino acid sequences were determined, and their catalytic and molecular properties were studied. Cells anaerobically grown on benzoate and nitrate contain one CoA ligase (AMP forming) for benzoic acid (E1). It is a homodimer of Mr 120,000 which prefers benzoate as a substrate but shows some activity also with 2-aminobenzoate and fluorobenzoates, although with lower Km. Cells anaerobically grown on 2-aminobenzoate and nitrate contain three different CoA ligases for aromatic acids. The first one is identical with benzoate-CoA ligase (E1). The second enzyme is a 2-aminobenzoate-CoA ligase (E2). It is a monomer of Mr 60,000 which prefers 2-aminobenzoate but also activates benzoate, fluorobenzoates and, less effectively, 2-methylbenzoate, with lower affinities to the latter substrates. The enzymes E1 and E2 have similar activity levels; a third minor CoA ligase activity is due to a different 2-aminobenzoate-CoA ligase. The enzyme (E3) is a monomer of Mr, 65,000 which 2-aminobenzoate pathway (U. Altenschmidt, C. Eckerskorn, and G. Fuchs, Eur. J. Biochem. 194:647-653, 1990); apparently, it is not completely repressed under anaerobic conditions and therefore also is induced to a small extent by 2-aminobenzoate under anaerobic growth conditions. Images PMID:1885526

  14. Plutonium Interactions with Pseudomonas sp. and its Extracellular Polymeric Substances (Sorption and Reduction of Plutonium by Bacterial Extracellular Polymeric Substances)

    SciTech Connect

    Boggs, Mark A.; Jiao, Yongqin; Dai, Zurong; Zavarin, Mavrik; Kersting, Annie B.

    2016-09-30

    Safe and effective nuclear waste disposal, as well as accidental radionuclide releases, necessitates our understanding of the fate of radionuclides in the environment, including their interaction with microorganisms. We examined the sorption of Pu(IV) and Pu(V) toPseudomonassp. strain EPS-1W, an aerobic bacterium isolated from plutonium (Pu) contaminated groundwater collected in the United States at the Nevada National Security Site (NNSS), Nevada. We compared Pu sorption to cells with and without bound extracellular polymeric substances (EPS). Wild type cells with intact EPS sorbed Pu(V) more effectively than cells with EPS removed. In contrast, cells with and without EPS showed the same sorption affinity for Pu(IV).In vitroexperiments with extracted EPS revealed rapid reduction of Pu(V) to Pu(IV). Transmission Electron Microscopy indicated that 2-3 nm nanocrystalline Pu(IV)O2formed on cells equilibrated with high concentrations of Pu(IV) but not Pu(V). Thus, EPS, while facilitating Pu(V) reduction, inhibit the formation of nanocrystalline Pu(IV) precipitates.

    ImportanceOur results indicate that EPS are an effective reductant for Pu(V) and sorbent for Pu(IV), and may impact Pu redox cycling and mobility in the environment. Additionally, the resulting Pu morphology associated with EPS will depend on the concentration and initial Pu oxidation state. While our results are not directly applicable to the Pu transport situation at the NNSS, the results suggest that, in general, stationary microorganisms and biofilms will tend to limit the migration of Pu and provide an important Pu retardation mechanism in the environment. In a broader sense, our results along with a growing body of literature highlight the important role of microorganisms as producers of redox-active organic ligands and therefore as modulators of radionuclide redox transformations and complexation in the subsurface.

  15. Cloning and Expression of ntnD, Encoding a Novel NAD(P)+-Independent 4-Nitrobenzyl Alcohol Dehydrogenase from Pseudomonas sp. Strain TW3

    PubMed Central

    James, Keith D.; Hughes, Michelle A.; Williams, Peter A.

    2000-01-01

    Pseudomonas sp. strain TW3 is able to metabolize 4-nitrotoluene to 4-nitrobenzoate and toluene to benzoate aerobically via a route analogous to the upper pathway of the TOL plasmids. We report the cloning and characterization of a benzyl alcohol dehydrogenase gene (ntnD) which encodes the enzyme for the catabolism of 4-nitrobenzyl alcohol and benzyl alcohol to 4-nitrobenzaldehyde and benzaldehyde, respectively. The gene is located downstream of the previously reported ntn gene cluster. NtnD bears no similarity to the analogous TOL plasmid XylB (benzyl alcohol dehydrogenase) protein either in its biochemistry, being NAD(P)+ independent and requiring assay via dye-linked electron transfer, or in its deduced amino acid sequence. It does, however, have significant similarity in its amino acid sequence to other NAD(P)+-independent alcohol dehydrogenases and contains signature patterns characteristic of type III flavin adenine dinucleotide-dependent alcohol oxidases. Reverse transcription-PCR demonstrated that ntnD is transcribed during growth on 4-nitrotoluene, although apparently not as part of the same transcript as the other ntn genes. The substrate specificity of the enzyme expressed from the cloned and overexpressed gene was similar to the activity expressed from strain TW3 grown on 4-nitrotoluene, providing evidence that ntnD is the previously unidentified gene in the pathway of 4-nitrotoluene catabolism. Examination of the 14.8-kb region around the ntn genes suggests that one or more recombination events have been involved in the formation of their current organization. PMID:10809692

  16. ntn Genes Determining the Early Steps in the Divergent Catabolism of 4-Nitrotoluene and Toluene in Pseudomonas sp. Strain TW3

    PubMed Central

    James, Keith D.; Williams, Peter A.

    1998-01-01

    Pseudomonas sp. strain TW3 is able to oxidatively metabolize 4-nitrotoluene and toluene via a route analogous to the upper pathway of the TOL plasmids. We report the sequence and organization of five genes, ntnWCMAB*, which are very similar to and in the same order as the xyl operon of TOL plasmid pWW0 and present evidence that they encode enzymes which are expressed during growth on both 4-nitrotoluene and toluene and are responsible for their oxidation to 4-nitrobenzoate and benzoate, respectively. These genes encode an alcohol dehydrogenase homolog (ntnW), an NAD+-linked benzaldehyde dehydrogenase (ntnC), a two-gene toluene monooxygenase (ntnMA), and part of a benzyl alcohol dehydrogenase (ntnB*), which have 84 to 99% identity at the nucleotide and amino acid levels with the corresponding xylWCMAB genes. The xylB homolog on the TW3 genome (ntnB*) appears to be a pseudogene and is interrupted by a piece of DNA which destroys its functional open reading frame, implicating an additional and as-yet-unidentified benzyl alcohol dehydrogenase gene in this pathway. This conforms with the observation that the benzyl alcohol dehydrogenase expressed during growth on 4-nitrotoluene and toluene differs significantly from the XylB protein, requiring assay via dye-linked electron transfer rather than through a nicotinamide cofactor. The further catabolism of 4-nitrobenzoate and benzoate diverges in that the former enters the hydroxylaminobenzoate pathway as previously reported, while the latter is further metabolized via the β-ketoadipate pathway. PMID:9555884

  17. Tuning the specificity of the recombinant multicomponent toluene o-xylene monooxygenase from Pseudomonas sp. strain OX1 for the biosynthesis of tyrosol from 2-phenylethanol.

    PubMed

    Notomista, Eugenio; Scognamiglio, Roberta; Troncone, Luca; Donadio, Giuliana; Pezzella, Alessandro; Di Donato, Alberto; Izzo, Viviana

    2011-08-01

    Biocatalysis is today a standard technology for the industrial production of several chemicals, and the number of biotransformation processes running on a commercial scale is constantly increasing. Among biocatalysts, bacterial multicomponent monooxygenases (BMMs), a diverse group of nonheme diiron enzymes that activate dioxygen, are of primary interest due to their ability to catalyze a variety of complex oxidations, including reactions of mono- and dihydroxylation of phenolic compounds. In recent years, both directed evolution and rational design have been successfully used to identify the molecular determinants responsible for BMM regioselectivity and to improve their activity toward natural and nonnatural substrates. Toluene o-xylene monooxygenase (ToMO) is a BMM isolated from Pseudomonas sp. strain OX1 which hydroxylates a wide spectrum of aromatic compounds. In this work we investigate the use of recombinant ToMO for the biosynthesis in recombinant cells of Escherichia coli strain JM109 of 4-hydroxyphenylethanol (tyrosol), an antioxidant present in olive oil, from 2-phenylethanol, a cheap and commercially available substrate. We initially found that wild-type ToMO is unable to convert 2-phenylethanol to tyrosol. This was explained by using a computational model which analyzed the interactions between ToMO active-site residues and the substrate. We found that residue F176 is the major steric hindrance for the correct positioning of the reaction intermediate leading to tyrosol production into the active site of the enzyme. Several mutants were designed and prepared, and we found that the combination of different mutations at position F176 with mutation E103G allows ToMO to convert up to 50% of 2-phenylethanol into tyrosol in 2 h.

  18. Isolation and characterization of a novel paraffin wax-degrading bacterium, Pseudomonas sp strain PW-1, from petroleum-contaminated sites.

    PubMed

    Zhang, Y L; Liu, Z; Liu, T

    2016-06-10

    An isolate capable of degrading paraffin wax was isolated from petroleum-contaminated sites in Daqing, China, and identified as Pseudomonas sp strain PW-1 by analyzing the 16S rDNA sequence (GenBank accession No.: KF529529) as well as the biochemical and physiological characteristics. The optimized degradation conditions of the isolate were as follows: FeSO4 metal ion concentration of 0.01 g, temperature of 30°C, (NH4)2SO4 nitrogen source concentration of 1.5 g/L, and a carbon: nitrogen ratio of 10:1. Response surface methodology-based analysis of the culture time, inoculation amount, and initial pH of the medium revealed that the optimal theoretical conditions were a culture time of 11.16 days, inoculation amount of 3.13%, and an initial pH of 9.29. The theoretical degradation rate was up to 54.68% under the optimal conditions. Taking into account the experimental conditions of a laboratory, 11.2 days of cultivating time, 3% inoculum, and a medium initial pH of 9.3 were used in practical settings. Experimental results showed that the degradation rate of paraffin wax was 52.85%, which demonstrated that this strain could degrade 1050 mg paraffin wax, using it as the sole carbon source, in a 1000-mL minimal salts medium. These results indicate that the strain PW1 can be used for application in oil wells with paraffin deposition problems in order to enhance oil recovery.

  19. Characterization of a Nitrilase and a Nitrile Hydratase from Pseudomonas sp. Strain UW4 That Converts Indole-3-Acetonitrile to Indole-3-Acetic Acid

    PubMed Central

    Rose, David R.; Glick, Bernard R.

    2014-01-01

    Indole-3-acetic acid (IAA) is a fundamental phytohormone with the ability to control many aspects of plant growth and development. Pseudomonas sp. strain UW4 is a rhizospheric plant growth-promoting bacterium that produces and secretes IAA. While several putative IAA biosynthetic genes have been reported in this bacterium, the pathways leading to the production of IAA in strain UW4 are unclear. Here, the presence of the indole-3-acetamide (IAM) and indole-3-acetaldoxime/indole-3-acetonitrile (IAOx/IAN) pathways of IAA biosynthesis is described, and the specific role of two of the enzymes (nitrilase and nitrile hydratase) that mediate these pathways is assessed. The genes encoding these two enzymes were expressed in Escherichia coli, and the enzymes were isolated and characterized. Substrate-feeding assays indicate that the nitrilase produces both IAM and IAA from the IAN substrate, while the nitrile hydratase only produces IAM. The two nitrile-hydrolyzing enzymes have very different temperature and pH optimums. Nitrilase prefers a temperature of 50°C and a pH of 6, while nitrile hydratase prefers 4°C and a pH of 7.5. Based on multiple sequence alignments and motif analyses, physicochemical properties and enzyme assays, it is concluded that the UW4 nitrilase has an aromatic substrate specificity. The nitrile hydratase is identified as an iron-type metalloenzyme that does not require the help of a P47K activator protein to be active. These data are interpreted in terms of a preliminary model for the biosynthesis of IAA in this bacterium. PMID:24837382

  20. Characterization of a para-nitrophenol catabolic cluster in Pseudomonas sp. strain NyZ402 and construction of an engineered strain capable of simultaneously mineralizing both para- and ortho-nitrophenols.

    PubMed

    Wei, Qing; Liu, Hong; Zhang, Jun-Jie; Wang, Song-He; Xiao, Yi; Zhou, Ning-Yi

    2010-07-01

    Pseudomonas sp. strain NyZ402 was isolated for its ability to grow on para-nitrophenol (PNP) as a sole source of carbon, nitrogen, and energy, and was shown to degrade PNP via an oxidization pathway. This strain was also capable of growing on hydroquinone or catechol. A 15, 818 bp DNA fragment extending from a 800-bp DNA fragment of hydroxyquinol 1,2-dioxygenase gene (pnpG) was obtained by genome walking. Sequence analysis indicated that the PNP catabolic gene cluster (pnpABCDEFG) in this fragment shared significant similarities with a recently reported gene cluster responsible for PNP degradation from Pseudomonas sp. strain WBC-3. PnpA is PNP 4-monooxygenase converting PNP to hydroquinone via benzoquinone in the presence of NADPH, and genetic analysis indicated that pnpA plays a key role in PNP degradation. pnpA1 present in the upstream of the cluster (absent in the cluster from strain WBC-3) encodes a protein sharing as high as 55% identity with PnpA, but was not involved in PNP degradation by either in vitro or in vivo analyses. Furthermore, an engineered strain capable of growing on PNP and ortho-nitrophenol (ONP) was constructed by introducing onpAB (encoding ONP monooxygenase and ortho-benzoquinone reductase which catalyzed the transformation of ONP to catechol) from Alcaligenes sp. strain NyZ215 into strain NyZ402.

  1. Physical and metabolic interactions of Pseudomonas sp. strain JA5-B45 and Rhodococcus sp. strain F9-D79 during growth on crude oil and effect of a chemical surfactant on them.

    PubMed

    Van Hamme, J D; Ward, O P

    2001-10-01

    Methods to enhance crude oil biodegradation by mixed bacterial cultures, for example, (bio)surfactant addition, are complicated by the diversity of microbial populations within a given culture. The physical and metabolic interactions between Rhodococcus sp. strain F9-D79 and Pseudomonas sp. strain JA5-B45 were examined during growth on Bow River crude oil. The effects of a nonionic chemical surfactant, Igepal CO-630 (nonylphenol ethoxylate), also were evaluated. Strain F9-D79 grew attached to the oil-water interface and produced a mycolic acid-containing capsule. Crude oil emulsification and surface activity were associated with the cellular fraction. Strain JA5-B45 grew in the aqueous phase and was unable to emulsify oil, but cell-free supernatants mediated kerosene-water emulsion formation. In coculture, stable emulsions were formed and strain JA5-B45 had an affinity for the capsule produced by strain F9-D79. Igepal CO-630 inhibited F9-D79 cells from adhering to the interface, and cells grew dispersed in the aqueous phase as 0.5-microm cocci rather than 2.5-microm rods. The surfactant increased total petroleum hydrocarbon removal by strain JA5-B45 from 4 to 22% and included both saturated compounds and aromatics. In coculture, TPH removal increased from 13 to 40% following surfactant addition. The culture pH normally increased from 7.0 to between 7.5 and 8.5, although addition of Igepal CO-630 to F9-D79 cultures resulted in a drop to pH 5.5. We suggest a dual role for the nonylphenol ethoxylate surfactant in the coculture: (i) to improve hydrocarbon uptake by strain JA5-B45 through emulsification and (ii) to prevent strain F9-D79 from adhering to the oil-water interface, indirectly increasing hydrocarbon availability. These varied effects on hydrocarbon biodegradation could explain some of the known diversity of surfactant effects.

  2. Physical and Metabolic Interactions of Pseudomonas sp. Strain JA5-B45 and Rhodococcus sp. Strain F9-D79 during Growth on Crude Oil and Effect of a Chemical Surfactant on Them

    PubMed Central

    Van Hamme, Jonathan D.; Ward, Owen P.

    2001-01-01

    Methods to enhance crude oil biodegradation by mixed bacterial cultures, for example, (bio)surfactant addition, are complicated by the diversity of microbial populations within a given culture. The physical and metabolic interactions between Rhodococcus sp. strain F9-D79 and Pseudomonas sp. strain JA5-B45 were examined during growth on Bow River crude oil. The effects of a nonionic chemical surfactant, Igepal CO-630 (nonylphenol ethoxylate), also were evaluated. Strain F9-D79 grew attached to the oil-water interface and produced a mycolic acid-containing capsule. Crude oil emulsification and surface activity were associated with the cellular fraction. Strain JA5-B45 grew in the aqueous phase and was unable to emulsify oil, but cell-free supernatants mediated kerosene-water emulsion formation. In coculture, stable emulsions were formed and strain JA5-B45 had an affinity for the capsule produced by strain F9-D79. Igepal CO-630 inhibited F9-D79 cells from adhering to the interface, and cells grew dispersed in the aqueous phase as 0.5-μm cocci rather than 2.5-μm rods. The surfactant increased total petroleum hydrocarbon removal by strain JA5-B45 from 4 to 22% and included both saturated compounds and aromatics. In coculture, TPH removal increased from 13 to 40% following surfactant addition. The culture pH normally increased from 7.0 to between 7.5 and 8.5, although addition of Igepal CO-630 to F9-D79 cultures resulted in a drop to pH 5.5. We suggest a dual role for the nonylphenol ethoxylate surfactant in the coculture: (i) to improve hydrocarbon uptake by strain JA5-B45 through emulsification and (ii) to prevent strain F9-D79 from adhering to the oil-water interface, indirectly increasing hydrocarbon availability. These varied effects on hydrocarbon biodegradation could explain some of the known diversity of surfactant effects. PMID:11571196

  3. Kinetics of nutrient enhanced crude oil degradation by Pseudomonas aeruginosa AKS1 and Bacillus sp. AKS2 isolated from Guwahati refinery, India.

    PubMed

    Chettri, Bobby; Mukherjee, Arghya; Langpoklakpam, James S; Chattopadhyay, Dhrubajyoti; Singh, Arvind K

    2016-09-01

    Bacterial degradation of crude oil in response to nutrient treatments has been vastly studied. But there is a paucity of information on kinetic parameters of crude oil degradation. Here we report the nutrient stimulated kinetic parameters of crude oil degradation assessed in terms of CO2 production and oil removal by Pseudomonas aeruginosa AKS1 and Bacillus sp. AKS2. The hydrocarbon degradation rate of P. aeruginosa AKS1 in oil only amended sediment was 10.75 ± 0.65 μg CO2-C g(-1) sediment day(-1) which was similar to degradation rate in sediments with no oil. In presence of both inorganic N & P, the degradation rate increased to 47.22 ± 1.32 μg CO2-C g(-1) sediment day(-1). The half-saturation constant (Ks) and maximum degradation rate (Vmax) for P. aeruginosa AKS1 under increasing N and saturating P concentration were 13.57 ± 0.53 μg N g(-1) sediment and 39.36 ± 1.42 μg CO2-C g(-1) sediment day(-1) respectively. The corresponding values at increasing P and a constant N concentration were 1.60 ± 0.13 μg P g(-1) sediment and 43.90 ± 1.03 μg CO2-C g(-1) sediment day(-1) respectively. Similarly the degradation rate of Bacillus sp. AKS2 in sediments amended with both inorganic nutrients N & P was seven fold higher than the rates in oil only or nutrient only treated sediments. The Ks and Vmax estimates of Bacillus sp. AKS2 under increasing N and saturating P concentration were 9.96 ± 1.25 μg N g(-1) sediment and 59.96 ± 7.56 μg CO2-C g(-1) sediment day(-1) respectively. The corresponding values for P at saturating N concentration were 0.46 ± 0.24 μg P g(-1) sediment and 63.63 ± 3.54 μg CO2-C g(-1) sediment day(-1) respectively. The rates of CO2 production by both isolates were further stimulated when oil concentration was increased above 12.5 mg g(-1) sediment. However, oil degradation activity declined at oil concentration above 40 mg g(-1) sediment when treated with constant nutrient: oil ratio

  4. Sulfur source-mediated transcriptional regulation of the rhlABC genes involved in biosurfactants production by Pseudomonas sp. strain AK6U

    PubMed Central

    Ismail, Wael; El Nayal, Ashraf M.; Ramadan, Ahmed R.; Abotalib, Nasser

    2014-01-01

    Despite the nutritional significance of sulfur, its influence on biosurfactants production has not been sufficiently studied. We investigated the expression of key biosurfactants production genes, rhlABC, in cultures of Pseudomonas sp. AK6U grown with inorganic or organic sulfur sources. AK6U grew with either inorganic sulfate (MgSO4), dibenzothiophene (DBT), or DBT-sulfone as a sole sulfur source in the presence of glucose as a carbon source. The AK6U cultures produced variable amounts of biosurfactants depending on the utilized sulfur source. Biosurfactants production profile of the DBT cultures was significantly different from that of the DBT-sulfone and inorganic sulfate cultures. The last two cultures were very similar in terms of biosurfactants productivity. Biosurfactants yield in the DBT cultures (1.3 g/L) was higher than that produced by the DBT-sulfone (0.5 g/L) and the inorganic sulfate (0.44 g/L) cultures. Moreover, the surface tension reduction in the DBT cultures (33 mN/m) was much stronger than that measured in the DBT-sulfone (58 mN/m) or inorganic sulfate (54 mN/m) cultures. RT-qPCR revealed variations in the expression levels of the rhlABC genes depending on the sulfur source. The DBT cultures had higher expression levels for the three genes as compared to the DBT-sulfone and inorganic sulfate cultures. There was no significant difference in the expression profiles between the DBT-sulfone and the MgSO4 cultures. The increased expression of rhlC in the DBT cultures is indicative for production of higher amounts of dirhamnolipids compared to the DBT-sulfone and inorganic sulfate cultures. The gene expression results were in good agreement with the biosurfactants production yields and surface tension measurements. The sulfur source mediates a fine-tuned mechanism of transcriptional regulation of biosurfactants production genes. Our findings can have an impact on industrial production of biosurfactants and other biotechnological processes like

  5. Sulfur source-mediated transcriptional regulation of the rhlABC genes involved in biosurfactants production by Pseudomonas sp. strain AK6U.

    PubMed

    Ismail, Wael; El Nayal, Ashraf M; Ramadan, Ahmed R; Abotalib, Nasser

    2014-01-01

    Despite the nutritional significance of sulfur, its influence on biosurfactants production has not been sufficiently studied. We investigated the expression of key biosurfactants production genes, rhlABC, in cultures of Pseudomonas sp. AK6U grown with inorganic or organic sulfur sources. AK6U grew with either inorganic sulfate (MgSO4), dibenzothiophene (DBT), or DBT-sulfone as a sole sulfur source in the presence of glucose as a carbon source. The AK6U cultures produced variable amounts of biosurfactants depending on the utilized sulfur source. Biosurfactants production profile of the DBT cultures was significantly different from that of the DBT-sulfone and inorganic sulfate cultures. The last two cultures were very similar in terms of biosurfactants productivity. Biosurfactants yield in the DBT cultures (1.3 g/L) was higher than that produced by the DBT-sulfone (0.5 g/L) and the inorganic sulfate (0.44 g/L) cultures. Moreover, the surface tension reduction in the DBT cultures (33 mN/m) was much stronger than that measured in the DBT-sulfone (58 mN/m) or inorganic sulfate (54 mN/m) cultures. RT-qPCR revealed variations in the expression levels of the rhlABC genes depending on the sulfur source. The DBT cultures had higher expression levels for the three genes as compared to the DBT-sulfone and inorganic sulfate cultures. There was no significant difference in the expression profiles between the DBT-sulfone and the MgSO4 cultures. The increased expression of rhlC in the DBT cultures is indicative for production of higher amounts of dirhamnolipids compared to the DBT-sulfone and inorganic sulfate cultures. The gene expression results were in good agreement with the biosurfactants production yields and surface tension measurements. The sulfur source mediates a fine-tuned mechanism of transcriptional regulation of biosurfactants production genes. Our findings can have an impact on industrial production of biosurfactants and other biotechnological processes like

  6. Reclassification of Alcaligenes latus strains IAM 12599T and IAM 12664 and Pseudomonas saccharophila as Azohydromonas lata gen. nov., comb. nov., Azohydromonas australica sp. nov. and Pelomonas saccharophila gen. nov., comb. nov., respectively.

    PubMed

    Xie, Cheng-Hui; Yokota, Akira

    2005-11-01

    The aim of this study was to clarify the taxonomic position of the nitrogen-fixing and hydrogen-oxidizing bacteria Alcaligenes latus strains IAM 12599T, IAM 12664 and IAM 12665 and Pseudomonas saccharophila IAM 14368T. It was found that the type strain of Alcaligenes latus, IAM 12599T, showed 99 x 9 and 96 x 1 % 16S rRNA gene sequence similarity to strains IAM 12665 and IAM 12664, respectively. A comparison using DNA-DNA hybridization suggested that strains IAM 12599T and IAM 12665 belong to a single species (89 x 7 %) and that strain IAM 12664 (35 x 1 %) forms a separate species. The phenotypic characteristics also support the conclusion that these bacteria should be identified as two species of a new genus: Azohydromonas lata gen. nov., comb. nov. (type strain IAM 12599T=DSM 1122T=LMG 3321T=ATCC 29712T; reference strain IAM 12665=DSM 1123=LMG 3325=ATCC 29714) and Azohydromonas australica sp. nov. (type strain IAM 12664T=DSM 1124T=LMG 3324T=ATCC 29713T). Pseudomonas saccharophila IAM 14368T was found to be closely related to the phototrophic bacterium Roseateles depolymerans, with 96 x 8 % 16S rRNA gene sequence similarity, but the two bacteria are quite different with respect to their metabolism and some significant phenotypic characteristics, suggesting that they cannot be included in a single genus. Further studies on their nifH gene sequences, G+C content of the DNA and cellular fatty acid composition confirm that Pseudomonas saccharophila should be reclassified: the name Pelomonas saccharophila gen. nov., comb. nov. is proposed, with the type strain IAM 14368T (=LMG 2256T=ATCC 15946T).

  7. Two Inducible Prophages of an Antarctic Pseudomonas sp. ANT_H14 Use the Same Capsid for Packaging Their Genomes – Characterization of a Novel Phage Helper-Satellite System

    PubMed Central

    Dziewit, Lukasz; Radlinska, Monika

    2016-01-01

    Two novel prophages ФAH14a and ФAH14b of a psychrotolerant Antarctic bacterium Pseudomonas sp. ANT_H14 have been characterized. They were simultaneously induced with mitomycin C and packed into capsids of the same size and protein composition. The genome sequences of ФAH14a and ФAH14b have been determined. ФAH14b, the phage with a smaller genome (16,812 bp) seems to parasitize ФAH14a (55,060 bp) and utilizes its capsids, as only the latter encodes a complete set of structural proteins. Both viruses probably constitute a phage helper-satellite system, analogous to the P2-P4 duo. This study describes the architecture and function of the ФAH14a and ФAH14b genomes. Moreover, a functional analysis of a ФAH14a-encoded lytic enzyme and a DNA methyltransferase was performed. In silico analysis revealed the presence of the homologs of ФAH14a and ФAH14b in other Pseudomonas genomes, which may suggest that helper-satellite systems related to the one described in this work are common in pseudomonads. PMID:27387973

  8. The ppuI-rsaL-ppuR quorum-sensing system regulates cellular motility, pectate lyase activity, and virulence in potato opportunistic pathogen Pseudomonas sp. StFLB209.

    PubMed

    Kato, Taro; Morohoshi, Tomohiro; Someya, Nobutaka; Ikeda, Tsukasa

    2015-01-01

    Pseudomonas sp. StFLB209 was isolated from potato leaf as an N-acylhomoserine lactone (AHL)-producing bacterium and showed a close phylogenetic relationship with P. cichorii, a known plant pathogen. Although there are no reports of potato disease caused by pseudomonads in Japan, StFLB209 was pathogenic to potato leaf. In this study, we reveal the complete genome sequence of StFLB209, and show that the strain possesses a ppuI-rsaL-ppuR quorum-sensing system, the sequence of which shares a high similarity with that of Pseudomonas putida. Disruption of ppuI results in a loss of AHL production as well as remarkable reduction in motility. StFLB209 possesses strong pectate lyase activity and causes maceration on potato tuber and leaf, which was slightly reduced in the ppuI mutant. These results suggest that the quorum-sensing system is well conserved between StFLB209 and P. putida and that the system is essential for motility, full pectate lyase activity, and virulence in StFLB209.

  9. A Gene Cluster Involved in Degradation of Substituted Salicylates via ortho Cleavage in Pseudomonas sp. Strain MT1 Encodes Enzymes Specifically Adapted for Transformation of 4-Methylcatechol and 3-Methylmuconate▿

    PubMed Central

    Cámara, Beatriz; Bielecki, Piotr; Kaminski, Filip; dos Santos, Vitor Martins; Plumeier, Iris; Nikodem, Patricia; Pieper, Dietmar H.

    2007-01-01

    Pseudomonas sp. strain MT1 has recently been reported to degrade 4- and 5-chlorosalicylate by a pathway assumed to consist of a patchwork of reactions comprising enzymes of the 3-oxoadipate pathway. Genes encoding the initial steps in the degradation of salicylate and substituted derivatives were now localized and sequenced. One of the gene clusters characterized (sal) showed a novel gene arrangement, with salA, encoding a salicylate 1-hydroxylase, being clustered with salCD genes, encoding muconate cycloisomerase and catechol 1,2-dioxygenase, respectively, and was expressed during growth on salicylate and chlorosalicylate. A second gene cluster (cat), exhibiting the typical catRBCA arrangement of genes of the catechol branch of the 3-oxoadipate pathway in Pseudomonas strains, was expressed during growth on salicylate. Despite their high sequence similarities with isoenzymes encoded by the cat gene cluster, the catechol 1,2-dioxygenase and muconate cycloisomerase encoded by the sal cluster showed unusual kinetic properties. Enzymes were adapted for turnover of 4-chlorocatechol and 3-chloromuconate; however, 4-methylcatechol and 3-methylmuconate were identified as the preferred substrates. Investigation of the substrate spectrum identified 4- and 5-methylsalicylate as growth substrates, which were effectively converted by enzymes of the sal cluster into 4-methylmuconolactone, followed by isomerization to 3-methylmuconolactone. The function of the sal gene cluster is therefore to channel both chlorosubstituted and methylsubstituted salicylates into a catechol ortho cleavage pathway, followed by dismantling of the formed substituted muconolactones through specific pathways. PMID:17172348

  10. Draft Genome Sequence of a Pseudomonas sp. Strain Carrying blaIMP-25 and blaVIM-2 Carbapenemase Genes from Hospital Sewage

    PubMed Central

    Hu, Yiyi; Wu, Wenjing; Feng, Yu; Zhang, Xiaoxia

    2016-01-01

    Pseudomonas strain WCHP16 recovered from hospital sewage in West China Hospital, Chengdu, China was found to carry two carbapenemase genes blaIMP-25 and blaVIM-2. Here, we report its 5.7-Mb draft genome sequence, comprising 141 contigs and an average 59.53% G+C content. The genome contained 5,504 coding sequences and 67 tRNA genes. PMID:27795238

  11. Mcl-PHAs produced by Pseudomonas sp. Gl01 using fed-batch cultivation with waste rapeseed oil as carbon source.

    PubMed

    Mozejko, Justyna; Wilke, Andreas; Przybyłek, Grzegorz; Ciesielski, Slawomir

    2012-03-01

    The present study describes medium-chain-length polyhydroxyalkanoates (mcl-PHAs) production by the Pseudomonas Gl01 strain isolated from mixed microbial communities utilized for PHAs synthesis. A two-step fedbatch fermentation was conducted with glucose and waste rapeseed oil as the main carbon source for obtaining cell growth and mcl-PHAs accumulation, respectively. The results show that the Pseudomonas Gl01 strain is capable of growing and accumulating mcl-PHAs using a waste oily carbon source. The biomass value reached 3.0 g/l of CDW with 20% of PHAs content within 48 h of cultivation. The polymer was purified from lyophilized cells and analyzed by gas chromatography (GC). The results revealed that the monomeric composition of the obtained polyesters depended on the available substrate. When glucose was used in the growth phase, 3-hydroxyundecanoate and 3- hydroxydodecanoate were found in the polymer composition, whereas in the PHAs-accumulating stage, the Pseudomonas Gl01 strain synthesized mcl-PHAs consisting mainly of 3- hydroxyoctanoate and 3-hydroxydecanoate. The transcriptional analysis using reverse-transcription real-time PCR reaction revealed that the phaC1 gene could be transcribed simultaneously to the phaZ gene.

  12. Atropine Metabolism by Pseudomonas sp. Strain AT3: Evidence for Nortropine as an Intermediate in Tropine Breakdown and Reactions Leading to Succinate

    PubMed Central

    Bartholomew, B. A.; Smith, M. J.; Trudgill, P. W.; Hopper, D. J.

    1996-01-01

    Pseudomonas strain AT3, isolated by elective culture with atropine, hydrolyzed atropine and grew diauxically, first on the tropic acid and then on the tropine. Tropine was also used as a sole carbon and energy source. The methyl group of tropine was eliminated as formaldehyde, and the nortropine thus formed was a precursor of 6-hydroxycyclohepta-1,4-dione. Ammonia was detected as a product of nitrogen elimination. 6-Hydroxycyclohepta-1,4-dione was oxidized to cyclohepta-1,3,5-trione by an induced NAD(sup+)-specific dehydrogenase. Although cyclohepta-1,3,5-trione is a (beta)-diketone with two potential hydrolytic cleavage sites, an induced hydrolase was specific for one of these sites, with 4,6-dioxoheptanoate as the only hydrolysis product. Unlike the alternative cleavage product (3,6-dioxoheptanoate), this compound is also a (beta)-diketone, and a second hydrolytic cleavage formed succinate and acetone. Although Pseudomonas strain AT3 was not capable of growth with acetone, the compound was not detected in the culture medium and may have been lost to the atmosphere. Exhaustive experimentation with a wide range of conditions did not result in detection of the enzymes required for cleavage of the carbon-nitrogen bonds leading to the formation of nortropine and 6-hydroxycyclohepta-1,4-dione. PMID:16535398

  13. PSEUDOMONAS PYOCYANEA AND THE ARGININE DIHYDROLASE SYSTEM.

    PubMed

    TAYLOR, J J; WHITBY, J L

    1964-03-01

    Non-pigmented strains of Pseudomonas pyocyanea occur frequently and this organism has only limited activity in conventional biochemical tests; 50 strains were tested for the presence of arginine dihydrolase and found positive whereas only Salmonella sp. and Enterobacter sp. among other Gram-negative species were positive. The test for arginine dihydrolase is rapid and simple and suitable for routine use.

  14. Expression and characterization of thermotolerant lipase with broad pH profiles isolated from an Antarctic Pseudomonas sp strain AMS3

    PubMed Central

    2016-01-01

    A gene encoding a thermotolerant lipase with broad pH was isolated from an Antarctic Pseudomonas strain AMS3. The recombinant lipase AMS3 was purified by single-step purification using affinity chromatography, yielding a purification fold of approximately 1.52 and a recovery of 50%. The molecular weight was approximately ∼60 kDa including the strep and affinity tags. Interestingly, the purified Antarctic AMS3 lipase exhibited broad temperature profile from 10–70 °C and stable over a broad pH range from 5.0 to pH 10.0. Various mono and divalent metal ions increased the activity of the AMS3 lipase, but Ni2+ decreased its activity. The purified lipase exhibited the highest activity in the presence of sunflower oil. In addition, the enzyme activity in 25% v/v solvents at 50 °C particularly to n-hexane, DMSO and methanol could be useful for catalysis reaction in organic solvent and at broad temperature. PMID:27781152

  15. Chemotaxis and degradation of organophosphate compound by a novel moderately thermo-halo tolerant Pseudomonas sp. strain BUR11: evidence for possible existence of two pathways for degradation

    PubMed Central

    Pailan, Santanu

    2015-01-01

    An organophosphate (OP) degrading chemotactic bacterial strain BUR11 isolated from an agricultural field was identified as a member of Pseudomonas genus on the basis of its 16S rRNA gene sequence. The strain could utilize parathion, chlorpyrifos and their major hydrolytic intermediates as sole source of carbon for its growth and exhibited positive chemotactic response towards most of them. Optimum concentration of parathion for its growth was recorded to be 200 ppm and 62% of which was degraded within 96 h at 37 °C. Growth studies indicated the strain to be moderately thermo-halo tolerant in nature. Investigation based on identification of intermediates of parathion degradation by thin layer chromatography (TLC), high performance liquid chromatography (HPLC), gas chromatography (GC) and liquid chromatography mass spectrometry (LC-MS/MS) provided evidence for possible existence of two pathways. The first pathway proceeds via 4-nitrophenol (4-NP) while the second proceeds through formation of 4-aminoparathion (4-APar), 4-aminophenol (4-AP) and parabenzoquinone (PBQ). This is the first report of chemotaxis towards organophosphate compound by a thermo-halo tolerant bacterium. PMID:26587344

  16. The two-component regulators GacS and GacA positively regulate a nonfluorescent siderophore through the Gac/Rsm signaling cascade in high-siderophore-yielding Pseudomonas sp. strain HYS.

    PubMed

    Yu, Xinyan; Chen, Min; Jiang, Zhen; Hu, Yi; Xie, Zhixiong

    2014-09-01

    Siderophores, which are produced to overcome iron deficiency, are believed to be closely related to the adaptability of bacteria. The high-siderophore-yielding Pseudomonas sp. strain HYS simultaneously secretes the fluorescent siderophore pyoverdine and another nonfluorescent siderophore that is a major contributor to the high siderophore yield. Transposon mutagenesis revealed siderophore-related genes, including the two-component regulators GacS/GacA and a special cluster containing four open reading frames (the nfs cluster). Deletion mutations of these genes abolished nonfluorescent-siderophore production, and expression of the nfs cluster depended on gacA, indicating that gacS-gacA may control the nonfluorescent siderophore through regulation of the nfs cluster. Furthermore, regulation of the nonfluorescent siderophore by GacS/GacA involved the Gac/Rsm pathway. In contrast, inactivation of GacS/GacA led to upregulation of the fluorescent pyoverdine. The two siderophores were secreted under different iron conditions, probably because of differential effects of GacS/GacA. The global GacS/GacA regulatory system may control iron uptake by modulating siderophore production and may enable bacteria to adapt to changing iron environments.

  17. Phenazine-1-carboxamide (PCN) from Pseudomonas sp. strain PUP6 selectively induced apoptosis in lung (A549) and breast (MDA MB-231) cancer cells by inhibition of antiapoptotic Bcl-2 family proteins.

    PubMed

    Kennedy, R Kamaraj; Veena, V; Naik, P Ravindra; Lakshmi, Pragna; Krishna, R; Sudharani, S; Sakthivel, N

    2015-06-01

    Phenazine-1-carboxamide (PCN), a naturally occurring simple phenazine derivative isolated from Pseudomonas sp. strain PUP6, exhibited selective cytotoxic activity against lung (A549) and breast (MDA-MB-231) cancer cell lines in differential and dose-dependent manner compared to normal peripheral blood mononuclear cells. PCN-treated cancer cells showed the induction of apoptosis as evidenced by the release of low level of LDH, morphological characteristics, production of reactive oxygen species, loss of mitochondrial membrane potential (ΔΨm) and induction of caspase-3. At molecular level, PCN instigates apoptosis by mitochondrial intrinsic apoptotic pathway via the overexpression of p53, Bax, cytochrome C release and activation of caspase-3 with the inhibition of oncogenic anti-apoptotic proteins such as PARP and Bcl-2 family proteins (Bcl-2, Bcl-w and Bcl-xL). The in silico docking studies of PCN targeted against the anti-apoptotic members of Bcl-2 family proteins revealed the interaction of PCN with the BH3 domain, which might lead to the induction of apoptosis due to the inhibition of antiapoptotic proteins. Due to its innate inhibition potential of antiapoptotic Bcl-2 family proteins, PCN may be used as potent anticancer agent against both lung and breast cancer.

  18. Characterization of CpdC, a Large-Ring Lactone-Hydrolyzing Enzyme from Pseudomonas sp. Strain HI-70, and Its Use as a Fusion Tag Facilitating Overproduction of Proteins in Escherichia coli

    PubMed Central

    Xu, Yali; Grosse, Stephan; Iwaki, Hiroaki; Hasegawa, Yoshie

    2013-01-01

    There are few entries of carbon-carbon bond hydrolases (EC 3.7.1.-) in the ExPASy database. In microbes, these enzymes play an essential role in the metabolism of alicyclic or aromatic compounds as part of the global carbon cycle. CpdC is a ω-pentadecalactone hydrolase derived from the degradation pathway of cyclopentadecanol or cyclopentadecanone by Pseudomonas sp. strain HI-70. CpdC was purified to homogeneity and characterized. It is active as a dimer of 56,000 Da with a subunit molecular mass of 33,349. Although CpdC has the highest activity and reaction rate (kcat) toward ω-pentadecalactone, its catalytic efficiency favors lauryl lactone as a substrate. The melting temperature (Tm) of CpdC was estimated to be 50.9 ± 0.1°C. The half-life of CpdC at 35°C is several days. By virtue of its high level of expression in Escherichia coli, the intact CpdC-encoding gene and progressive 3′-end deletions were employed in the construction of a series of fusion plasmid system. Although we found them in inclusion bodies, proof-of-concept of overproduction of three microbial cutinases of which the genes were otherwise expressed poorly or not at all in E. coli was demonstrated. On the other hand, two antigenic proteins, azurin and MPT63, were readily produced in soluble form. PMID:24038681

  19. Characterizing LipR from Pseudomonas sp. R0-14 and Applying in Enrichment of Polyunsaturated Fatty Acids from Algal Oil.

    PubMed

    Yang, Wenjuan; Xu, Li; Zhang, Houjin; Yan, Yunjun

    2015-11-01

    In this study, Pseudomonas R0-14, which was isolated from Arctic soil samples, showed a clear halo when grown on M9 medium agarose plates containing olive oil-rhodamine B as substrate, suggesting that it expressed putative lipase(s). A putative lipase gene, lipR, was cloned from R0-14 by genome walking and Touchdown PCR. lipR encodes a 562-amino-acid polypeptide showing a typical α/β hydrolase structure with a catalytic triad consisting of Ser153-Asp202-His260 and one α-helical lid (residues 103-113). A phylogenetic analysis revealed that LipR belongs to the lipase subfamily I.3. LipR was successfully expressed in Escherichia coli, purified, and biochemically characterized. Recombinant LipR exhibited its maximum activity towards p-nitrophenyl butyrate at pH 8.5 and 60°C with a Km of 0.37 mM and a kcat of 6.42 s(-1). It retained over 90% of its original activity after incubation at 50°C for 12 h. In addition, LipR was activated by Ca(2+), Mg(2+), Ba(2+), and Sr(2+), while strongly inhibited by Cu(2+), Zn(2+), Mn(2+), and ethylenediaminetetraacetic acid. Moreover, it showed a certain tolerance to organic solvents, including acetonitrile, isopropanol, acetone, methanol, and tert-butanol. When algal oil was hydrolyzed by LipR for 24 h, there was an enrichment of n-3 long-chain polyunsaturated fatty acids, including eicosapentaenoic acid (1.22%, 1.65-fold), docosapentaenoic acid (21.24%, 2.04-fold), and docosahexaenoic acid (36.98%, 1.33-fold), and even a certain amount of diacylglycerols was also produced. As a result, LipR has great prospect in industrial applications, especially in food and/or cosmetics applications.

  20. A cold-adapted lipase of an Alaskan psychrotroph, Pseudomonas sp. strain B11-1: gene cloning and enzyme purification and characterization.

    PubMed

    Choo, D W; Kurihara, T; Suzuki, T; Soda, K; Esaki, N

    1998-02-01

    A psychrotrophic bacterium producing a cold-adapted lipase upon growth at low temperatures was isolated from Alaskan soil and identified as a Pseudomonas strain. The lipase gene (lipP) was cloned from the strain and sequenced. The amino acid sequence deduced from the nucleotide sequence of the gene (924 bp) corresponded to a protein of 308 amino acid residues with a molecular weight of 33,714. LipP also has consensus motifs conserved in other cold-adapted lipases, i.e., Lipase 2 from Antarctic Moraxella TA144 (G. Feller, M. Thirty, J. L. Arpigny, and C. Gerday, DNA Cell Biol. 10:381-388, 1991) and the mammalian hormone-sensitive lipase (D. Langin, H. Laurell, L. S. Holst, P. Belfrage, and C. Holm, Proc. Natl. Acad. Sci. USA 90:4897-4901, 1993): a pentapeptide, GDSAG, containing the putative active-site serine and an HG dipeptide. LipP was purified from an extract of recombinant Escherichia coli C600 cells harboring a plasmid coding for the lipP gene. The enzyme showed a 1,3-positional specificity toward triolein. p-Nitrophenyl esters of fatty acids with short to medium chains (C4 and C6) served as good substrates. The enzyme was stable between pH 6 and 9, and the optimal pH for the enzymatic hydrolysis of tributyrin was around 8. The activation energies for the hydrolysis of p-nitrophenyl butyrate and p-nitrophenyl laurate were determined to be 11.2 and 7.7 kcal/mol, respectively, in the temperature range 5 to 35 degrees C. The enzyme was unstable at temperatures higher than 45 degrees C. The Km of the enzyme for p-nitrophenyl butyrate increased with increases in the assay temperature. The enzyme was strongly inhibited by Zn2+, Cu2+, Fe3+, and Hg2+ but was not affected by phenylmethylsulfonyl fluoride and bisnitrophenyl phosphate. Various water-miscible organic solvents, such as methanol and dimethyl sulfoxide, at concentrations of 0 to 30% (vol/vol) activated the enzyme.

  1. Sequence analysis of the Pseudomonas sp. strain P51 tcb gene cluster, which encodes metabolism of chlorinated catechols: evidence for specialization of catechol 1,2-dioxygenases for chlorinated substrates.

    PubMed Central

    van der Meer, J R; Eggen, R I; Zehnder, A J; de Vos, W M

    1991-01-01

    Pseudomonas sp. strain P51 contains two gene clusters located on catabolic plasmid pP51 that encode the degradation of chlorinated benzenes. The nucleotide sequence of a 5,499-bp region containing the chlorocatechol-oxidative gene cluster tcbCDEF was determined. The sequence contained five large open reading frames, which were all colinear. The functionality of these open reading frames was studied with various Escherichia coli expression systems and by analysis of enzyme activities. The first gene, tcbC, encodes a 27.5-kDa protein with chlorocatechol 1,2-dioxygenase activity. The tcbC gene is followed by tcbD, which encodes cycloisomerase II (39.5 kDa); a large open reading frame (ORF3) with an unknown function; tcbE, which encodes hydrolase II (25.8 kDa); and tcbF, which encodes a putative trans-dienelactone isomerase (37.5 kDa). The tcbCDEF gene cluster showed strong DNA homology (between 57.6 and 72.1% identity) and an organization similar to that of other known plasmid-encoded operons for chlorocatechol metabolism, e.g., clcABD of Pseudomonas putida and tfdCDEF of Alcaligenes eutrophus JMP134. The identity between amino acid sequences of functionally related enzymes of the three operons varied between 50.6 and 75.7%, with the tcbCDEF and tfdCDEF pair being the least similar of the three. Measurements of the specific activities of chlorocatechol 1,2-dioxygenases encoded by tcbC, clcA, and tfdC suggested that a specialization among type II enzymes has taken place. TcbC preferentially converts 3,4-dichlorocatechol relative to other chlorinated catechols, whereas TfdC has a higher activity toward 3,5-dichlorocatechol. ClcA takes an intermediate position, with the highest activity level for 3-chlorocatechol and the second-highest level for 3,5-dichlorocatechol. Images PMID:2013566

  2. Pseudomonas chemotaxis.

    PubMed

    Sampedro, Inmaculada; Parales, Rebecca E; Krell, Tino; Hill, Jane E

    2015-01-01

    Pseudomonads sense changes in the concentration of chemicals in their environment and exhibit a behavioral response mediated by flagella or pili coupled with a chemosensory system. The two known chemotaxis pathways, a flagella-mediated pathway and a putative pili-mediated system, are described in this review. Pseudomonas shows chemotaxis response toward a wide range of chemicals, and this review includes a summary of them organized by chemical structure. The assays used to measure positive and negative chemotaxis swimming and twitching Pseudomonas as well as improvements to those assays and new assays are also described. This review demonstrates that there is ample research and intellectual space for future investigators to elucidate the role of chemotaxis in important processes such as pathogenesis, bioremediation, and the bioprotection of plants and animals.

  3. Simply enhancing throughput of free-flow electrophoresis via organic-aqueous environment for purification of weak polarity solute of phenazine-1-carboxylic acid in fermentation of Pseudomonas sp. M18.

    PubMed

    Yang, Jing-Hua; Shao, Jing; Wang, Hou-Yu; Dong, Jing-Yu; Fan, Liu-Yin; Cao, Cheng-Xi; Xu, Yu-Quan

    2012-09-01

    Herein, a simple novel free-flow electrophoresis (FFE) method was developed via introduction of organic solvent into the electrolyte system, increasing the solute solubility and throughput of the sample. As a proof of concept, phenazine-1-carboxylic acid (PCA) from Pseudomonas sp. M18 was selected as a model solute for the demonstration on feasibility of novel FFE method on account of its faint solubility in aqueous circumstance. In the developed method, the organic solvent was added into not only the sample buffer to improve the solubility of the solute, but also the background buffer to construct a uniform aqueous-organic circumstance. These factors of organic solvent percentage and types as well as pH value of background buffer were investigated for the purification of PCA in the FFE device via CE. The experiments revealed that the percentage and the types of organic solvent exerted major influence on the purification of PCA. Under the optimized conditions (30 mM phosphate buffer in 60:40 (v/v) water-methanol at an apparent pH 7.0, 3.26 mL/min background flux, 10-min residence time of injected sample, and 400 V), PCA could be continuously purified from its impurities. The flux of sample injection was 10.05 μL/min, and the recovery was up to 93.7%. An 11.9-fold improvement of throughput was found with a carrier buffer containing 40% (v/v) methanol, compared with the pure aqueous phase. The developed procedure is of evident significance for the purification of weak polarity solute via FFE.

  4. Degradation of aromatics and chloroaromatics by Pseudomonas sp. strain B13: purification and characterization of 3-oxoadipate:succinyl-coenzyme A (CoA) transferase and 3-oxoadipyl-CoA thiolase.

    PubMed

    Kaschabek, Stefan R; Kuhn, Bernd; Müller, Dagmar; Schmidt, Eberhard; Reineke, Walter

    2002-01-01

    The degradation of 3-oxoadipate in Pseudomonas sp. strain B13 was investigated and was shown to proceed through 3-oxoadipyl-coenzyme A (CoA) to give acetyl-CoA and succinyl-CoA. 3-Oxoadipate:succinyl-CoA transferase of strain B13 was purified by heat treatment and chromatography on phenyl-Sepharose, Mono-Q, and Superose 6 gels. Estimation of the native molecular mass gave a value of 115,000 +/- 5,000 Da with a Superose 12 column. Polyacrylamide gel electrophoresis under denaturing conditions resulted in two distinct bands of equal intensities. The subunit A and B values were 32,900 and 27,000 Da. Therefore it can be assumed that the enzyme is a heterotetramer of the type A2B2 with a molecular mass of 120,000 Da. The N-terminal amino acid sequences of both subunits are as follows: subunit A, AELLTLREAVERFVNDGTVALEGFTHLIPT; subunit B, SAYSTNEMMTVAAARRLKNGAVVFV. The pH optimum was 8.4. Km values were 0.4 and 0.2 mM for 3-oxoadipate and succinyl-CoA, respectively. Reversibility of the reaction with succinate was shown. The transferase of strain B13 failed to convert 2-chloro- and 2-methyl-3-oxoadipate. Some activity was observed with 4-methyl-3-oxoadipate. Even 2-oxoadipate and 3-oxoglutarate were shown to function as poor substrates of the transferase. 3-oxoadipyl-CoA thiolase was purified by chromatography on DEAE-Sepharose, blue 3GA, and reactive brown-agarose. Estimation of the native molecular mass gave 162,000 +/- 5,000 Da with a Superose 6 column. The molecular mass of the subunit of the denatured protein, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, was 42 kDa. On the basis of these results, 3-oxoadipyl-CoA thiolase should be a tetramer of the type A4. The N-terminal amino acid sequence of 3-oxoadipyl-CoA thiolase was determined to be SREVYI-DAVRTPIGRFG. The pH optimum was 7.8. Km values were 0.15 and 0.01 mM for 3-oxoadipyl-CoA and CoA, respectively. Sequence analysis of the thiolase terminus revealed high percentages of identity

  5. Pseudomonas 2007 Meeting Review

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pseudomonas is an important genus of bacteria. Pseudomonas aeruginosa is the third most common nosocomial pathogen in our society, associated with chronic and eventually fatal lung disease in cystic fibrosis patients, while Pseudomonas syringae species are prominent plant pathogens. The fluorescen...

  6. Isolation and evaluation of potent Pseudomonas species for bioremediation of phorate in amended soil.

    PubMed

    Jariyal, Monu; Gupta, V K; Jindal, Vikas; Mandal, Kousik

    2015-12-01

    Use of phorate as a broad spectrum pesticide in agricultural crops is finding disfavor due to persistence of both the principal compound as well as its toxic residues in soil. Three phorate utilizing bacterial species (Pseudomonas sp. strain Imbl 4.3, Pseudomonas sp. strain Imbl 5.1, Pseudomonas sp. strain Imbl 5.2) were isolated from field soils. Comparative phorate degradation analysis of these species in liquid cultures identified Pseudomonas sp. strain Imbl 5.1 to cause complete metabolization of phorate during seven days as compared to the other two species in 13 days. In soils amended with phorate at different levels (100, 200, 300 mg kg(-1) soil), Pseudomonas sp. strain Imbl 5.1 resulted in active metabolization of phorate by between 94.66% and 95.62% establishing the same to be a potent bacterium for significantly relieving soil from phorate residues. Metabolization of phorate to these phorate residues did not follow the first order kinetics. This study proves that Pseudomonas sp. strain Imbl 5.1 has huge potential for active bioremediation of phorate both in liquid cultures and agricultural soils.

  7. Degradation of polynuclear aromatic hydrocarbons by two strains of Pseudomonas.

    PubMed

    Nwinyi, Obinna C; Ajayi, Oluseyi O; Amund, Olukayode O

    2016-01-01

    The goal of this investigation was to isolate competent polynuclear aromatic hydrocarbons degraders that can utilize polynuclear aromatic hydrocarbons of former industrial sites at McDoel Switchyard in Bloomington, Indiana. Using conventional enrichment method based on soil slurry, we isolated, screened and purified two bacterial species strains PB1 and PB2. Applying the ribotyping technique using the 16S rRNA gene analysis, the strains were assigned to the genus Pseudomonas (Pseudomonas plecoglossicida strain PB1 and Pseudomonas sp. PB2). Both isolates showed promising metabolic capacity on pyrene sprayed MS agar plates during the preliminary investigations. Using time course studies in the liquid cultures at calculated concentrations 123, 64, 97 and 94ppm for naphthalene, chrysene, fluroanthene and pyrene, P. plecoglossicida strain PB1 and Pseudomonas sp. PB2 showed partial utilization of the polynuclear aromatic hydrocarbons. Naphthalene was degraded between 26% and 40%, chrysene 14% and 16%, fluroanthene 5% and 7%; pyrene 8% and 13% by P. plecoglossicida strain PB1 and Pseudomonas sp. PB2 respectively. Based on their growth profile, we developed a model R(2)=1 to predict the degradation rate of slow polynuclear aromatic hydrocarbon-degraders where all the necessary parameters are constant. From this investigation, we confirm that the former industrial site soil microbial communities may be explored for the biorestoration of the industrial site.

  8. Pseudomonas screening assay

    NASA Technical Reports Server (NTRS)

    Margalit, Ruth (Inventor)

    1993-01-01

    A method for the detection of Pseudomonas bacteria is described where an Azurin-specific antibody is employed for detecting the presence of Azurin in a test sample. The detection of the presence of Azurin in the sample is a conclusive indicator of the presence of the Pseudomonas bacteria since the Azurin protein is a specific marker for this bacterial strain.

  9. Complete Genome Sequence of Pseudomonas balearica DSM 6083T

    PubMed Central

    Salvà-Serra, Francisco; Jaén-Luchoro, Daniel; Seguí, Carolina; Aliaga, Francisco; Busquets, Antonio; Gomila, Margarita; Lalucat, Jorge

    2016-01-01

    The whole-genome sequence of Pseudomonas balearica SP1402 (DSM 6083T) has been completed and annotated. It was isolated as a naphthalene degrader from water of a lagooning wastewater treatment plant. P. balearica strains tolerate up to 8.5% NaCl and are considered true marine denitrifiers. PMID:27103708

  10. Monocyte Profiles in Critically Ill Patients With Pseudomonas Aeruginosa Sepsis

    ClinicalTrials.gov

    2017-02-02

    Pseudomonas Infections; Pseudomonas Septicemia; Pseudomonas; Pneumonia; Pseudomonal Bacteraemia; Pseudomonas Urinary Tract Infection; Pseudomonas Gastrointestinal Tract Infection; Sepsis; Sepsis, Severe; Critically Ill

  11. Induced Formation of Chelating Agents by Pseudomonas aeruginosa Grown in Presence of Thorium and Uranium

    DTIC Science & Technology

    1985-07-01

    Bacillus megaterium . Biochemistry 10(26):4894-4898 Nakahara H, Ishikawa T, Sarai Y, Kondo 1, Kozukue H, Silver S (1977) Linkage of mercury, cadmium...were isolated from low level radioactive waste disposal sites. They include Bacillus ap., Pseudomonas sp., Citrobacter sp. and Clostridium ap. (Francis

  12. Indicator For Pseudomonas Bacteria

    NASA Technical Reports Server (NTRS)

    Margalit, Ruth

    1990-01-01

    Characteristic protein extracted and detected. Natural protein marker found in Pseudomonas bacteria. Azurin, protein containing copper readily extracted, purified, and used to prepare antibodies. Possible to develop simple, fast, and accurate test for marker carried out in doctor's office.

  13. Pseudomonas orchitis in puberty.

    PubMed

    Rajagopal, Ambil S

    2004-10-01

    Acute epididymo-orchitis is a common cause of 'acute scrotum' in adolescence and young adults, and the common causative pathogens are Chlamydia trachomatis and Neisseria gonorrhoeae. This is a rare case of acute epididymo-orchitis due to Pseudomonas aeruginosa in a pubertal boy with a history of 'ano-receptive' intercourse. On Medline search there are no reports of pseudomonas orchitis in this age group.

  14. 40 CFR 180.1114 - Pseudomonas fluorescens A506, Pseudomonas fluorescens 1629RS, and Pseudomonas syringae 742RS...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Pseudomonas fluorescens A506, Pseudomonas fluorescens 1629RS, and Pseudomonas syringae 742RS; exemptions from the requirement of a tolerance... Tolerances § 180.1114 Pseudomonas fluorescens A506, Pseudomonas fluorescens 1629RS, and Pseudomonas...

  15. Polymicrobial ventriculitis involving Pseudomonas fulva.

    PubMed

    Rebolledo, Paulina A; Vu, Catphuong Cathy L; Carlson, Renee Donahue; Kraft, Colleen S; Anderson, Evan J; Burd, Eileen M

    2014-06-01

    Infections due to Pseudomonas fulva remain a rare but emerging concern. A case of ventriculitis due to Enterobacter cloacae and Pseudomonas fulva following placement of an external ventricular drain is described. Similar to other reports, the organism was initially misidentified as Pseudomonas putida. The infection was successfully treated with levofloxacin.

  16. Novel cyclic lipodepsipeptide from Pseudomonas syringae pv. lachrymans strain 508 and syringopeptin antimicrobial activities.

    PubMed

    Grgurina, Ingeborg; Bensaci, Mekki; Pocsfalvi, Gabriella; Mannina, Luisa; Cruciani, Oscar; Fiore, Alberto; Fogliano, Vincenzo; Sorensen, Kevin N; Takemoto, Jon Y

    2005-12-01

    The syringopeptins are a group of antimicrobial cyclic lipodepsipeptides produced by several plant-associated pseudomonads. A novel syringopeptin, SP508, was shown to be produced as two homologs (A and B) by Pseudomonas syringae pv. lachrymans strain 508 from apple and to structurally resemble syringopeptin SP22. SP508 differed from SP22 and other syringopeptins by having three instead of four alpha,beta-unsaturated amino acids and a longer beta-hydroxy acyl chain. Both SP508 and SP22 displayed growth-inhibitory activities against Mycobacterium smegmatis, other gram-positive bacteria, and yeasts but not against gram-negative bacteria. Structure-activity analyses of the SP508 and SP22 homologs indicated chemical structural features that lead to enhanced antimycobacterial activity by these pseudomonad cyclic lipodepsipeptides.

  17. Phenotypic and genotypic characterization of phenanthrene-degrading fluorescent Pseudomonas biovars

    SciTech Connect

    Johnsen, K.; Andersen, S.; Jacobsen, C.S.

    1996-10-01

    The genus Pseudomonas is a group of gram-negative motile rods know for large metabolic versatility as well as pathogenicity to plants, animals and humans. A large number of bacteria from this group capable of degrading polycyclic aromatic hydrocarbons have been isolated in soils and aquifers, but the identification is often conducted only to the Pseudomonas sp. level. This study aims to characterize a group of bacteria from the fluorescent Pseudomonas group degrading phenanthrene by four different methods to assess the bacterial diversity of the closely related group. 37 refs., 3 figs., 1 tab.

  18. Molecular cloning of the Pseudomonas carboxypeptidase G2 gene and its expression in Escherichia coli and Pseudomonas putida.

    PubMed Central

    Minton, N P; Atkinson, T; Sherwood, R F

    1983-01-01

    The gene coding for carboxypeptidase G2 was cloned from Pseudomonas sp. strain RS-16 into Escherichia coli W5445 by inserting Sau3A-generated DNA fragments into the BamHI site of pBR322. The plasmid isolated, pNM1, was restriction mapped, and the position of the gene on the 5.8-megadalton insert was pinpointed by subcloning. The expression of carboxypeptidase in E. coli was 100-fold lower than in the Pseudomonas sp. strain. When the cloned gene was subcloned into the Pseudomonas vector pKT230 and introduced into Pseudomonas putida 2440, a 30-fold increase in expression over that obtained in E. coli was observed. High expression (up to 5% soluble protein) was obtained in E. coli by subcloning a 3.1-megadalton Bg/II fragment into the BamHI site of pAT153. The increased expression was orientation dependent and is presumed to be due to transcriptional readthrough from the Tc promoter of the vector. Production of carboxypeptidase was shown to be induced (two-fold) by the presence of folic acid, and the mature protein was shown to be located in the periplasmic space of E. coli. Images PMID:6358192

  19. The chlorocatechol-catabolic transposon Tn5707 of Alcaligenes eutrophus NH9, carrying a gene cluster highly homologous to that in the 1,2,4-trichlorobenzene-degrading bacterium Pseudomonas sp. strain P51, confers the ability to grow on 3-chlorobenzoate.

    PubMed

    Ogawa, N; Miyashita, K

    1999-02-01

    Alcaligenes eutrophus (Ralstonia eutropha) NH9, isolated in Japan, utilizes 3-chlorobenzoate as its sole source of carbon and energy. Sequencing of the relevant region of plasmid pENH91 from strain NH9 revealed that the genes for the catabolic enzymes were homologous to the genes of the modified ortho-cleavage pathway. The genes from strain NH9 (cbnR-ABCD) showed the highest homology (89 to 100% identity at the nucleotide level) to the tcbR-CDEF genes on plasmid pP51 of the 1,2,4-trichlorobenzene-degrading bacterium Pseudomonas sp. strain P51, which was isolated in The Netherlands. The structure of the operon, including the lengths of open reading frames and intervening sequences, was completely conserved between the cbn and tcb genes. Most nucleotide substitutions were localized within and proximal to the cbnB (tcbD) gene. The difference in the chloroaromatics that the two strains could use as growth substrates seemed to be due to differences in enzymes that convert substrates to chlorocatechols. The restriction map of plasmid pENH91 was clearly different from that of pP51 except in the regions that contained the cbnR-ABCD and tcbR-CDEF genes, respectively, suggesting that the chlorocatechol gene clusters might have been transferred as units. Two homologous sequences, present as direct repeats in both flanking regions of the cbnR-ABCD genes on pENH91, were found to be identical insertion sequences (ISs), designated IS1600, which formed a composite transposon designated Tn5707. Although the tcbR-CDEF genes were not associated with similar ISs, a DNA fragment homologous to IS1600 was cloned from the chromosome of strain P51. The sequence of the fragment suggested that it might be a remnant of an IS. The two sequences, together with IS1326 and nmoT, formed a distinct cluster on a phylogenetic tree of the IS21 family. The diversity of the sources of these IS or IS-like elements suggests the prevalence of ISs of this type.

  20. The chlorocatechol-catabolic transposon Tn5707 of Alcaligenes eutrophus NH9, carrying a gene cluster highly homologous to that in the 1,2,4-trichlorobenzene-degrading bacterium Pseudomonas sp. strain P51, confers the ability to grow on 3-chlorobenzoate

    SciTech Connect

    Ogawa, Naoto; Miyashita, Kiyotaka

    1999-02-01

    Alcaligenes eutrophus (Ralstonia eutropha) NH9, isolated in Japan, utilizes 3-chlorobenzoate as its sole source of carbon and energy. Sequencing of the relevant region of plasmid pENH91 from strain NH9 revealed that the genes for the catabolic enzymes were homologous to the genes of the modified ortho-cleavage pathway. The genes from strain NH9 (cbnR-ABCD) showed the highest homology to the tcbR-CDEF genes on plasmid pP51 of the 1,2,4-trichlorobenzene-degrading bacterium Pseudomonas sp. strain P51, which was isolated in The Netherlands. The structure of the operon, including the lengths of open reading frames and intervening sequences, was completely conserved between the cbn and tcb genes. Most nucleotide substitutions were localized within and proximal to the cbnB (tcbD) gene. The difference in the chloroaromatics that the two strains could use as growth substrates seemed to be due to differences in enzymes that convert substrates to chlorocatechols. The restriction map of plasmid pENH91 was clearly different from that of pP51 except in the regions that contained the cbnR-ABCD and tcbR-CDEF genes, respectively, suggesting that the chlorocatechol gene clusters might have been transferred as units. Two homologous sequences, present as direct repeats in both flanking regions of the cbnR-ABCD genes on pENH91, were found to be identical insertion sequences (ISs), designated IS1600, which formed a composite transposon designated Tn5707. Although the tcbR-CDEF genes were not associated with similar ISs, a DNA fragment homologous to IS/1600 was cloned from the chromosome of strain P51. The sequence of the fragment suggested that it might be a remnant of an IS. The two sequences, together with IS1326 and nmoT, formed a distinct cluster on a phylogenetic tree of the IS21 family. The diversity of the sources of these IS or IS-like elements suggests the prevalence of ISs of this type.

  1. Complete Genome Sequence of Pseudomonas aeruginosa FA-HZ1, an Efficient Dibenzofuran-Degrading Bacterium

    PubMed Central

    Ali, Fawad; Hu, Haiyang; Xu, Ping

    2017-01-01

    ABSTRACT Pseudomonas sp. FA-HZ1, an efficient dibenzofuran-degrading bacterium, was isolated from landfill leachate. Here, we present the complete genome sequence of strain FA-HZ1, which contains only one circular chromosome. The complete genome sequence will be essential for revealing the molecular mechanisms of dibenzofuran degradation. PMID:28209830

  2. Improved High-Quality Draft Genome Sequence of Pseudomonas fluorescens KENGFT3

    PubMed Central

    Town, Jennifer; Cui, Nina; Audy, Patrice; Boyetchko, Sue

    2016-01-01

    Pseudomonas sp. strain KENGFT3 inhibits the growth of Phytophthora infestans and is a potentially useful biopesticide for plant diseases, including potato late blight. We sequenced the 6.2-Mbp genome of this strain and assembled it into a single scaffold with 9 contigs. KENGFT3 is related to previously sequenced strains of P. fluorescens. PMID:27231365

  3. Evaluation of Pseudomonas syringae Strain ESC11 for Biocontrol of Crown Rot and Anthracnose of Banana

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pseudomonas syringae strain ESC11, and 250 'g/ml each of thiabendazole (TBZ) and imazalil reduced crown rot of banana caused by a Fusarium sp. by 0-88% and 73-88%, respectively, in laboratory experiments. ESC11 alone did not significantly reduce rot, mold, or anthracnose in most field trials. TBZ an...

  4. PSYCHROPHILIC PSEUDOMONAS SP. RESISTANT TO MERCURY FROM PAVLODAR, KAZAKHSTAN

    EPA Science Inventory

    As mercury circulates and deposits globally, the remediation of extensive mercury contamination surrounding a chloralkali plant in Pavlodar, Kazakhstan is critical. High-levels of mercury contamination exist within the confines of the plant, at nearby off-site waste storage and e...

  5. Biology of Pseudomonas stutzeri

    PubMed Central

    Lalucat, Jorge; Bennasar, Antoni; Bosch, Rafael; García-Valdés, Elena; Palleroni, Norberto J.

    2006-01-01

    Pseudomonas stutzeri is a nonfluorescent denitrifying bacterium widely distributed in the environment, and it has also been isolated as an opportunistic pathogen from humans. Over the past 15 years, much progress has been made in elucidating the taxonomy of this diverse taxonomical group, demonstrating the clonality of its populations. The species has received much attention because of its particular metabolic properties: it has been proposed as a model organism for denitrification studies; many strains have natural transformation properties, making it relevant for study of the transfer of genes in the environment; several strains are able to fix dinitrogen; and others participate in the degradation of pollutants or interact with toxic metals. This review considers the history of the discovery, nomenclatural changes, and early studies, together with the relevant biological and ecological properties, of P. stutzeri. PMID:16760312

  6. Chronic Pseudomonas aeruginosa cervical osteomyelitis

    PubMed Central

    Meher, Sujeet Kumar; Jain, Harsh; Tripathy, Laxmi Narayan; Basu, Sunandan

    2016-01-01

    Pseudomonas aeruginosa is a rare cause of osteomyelitis of the cervical spine and is usually seen in the background of intravenous drug use and immunocompromised state. Very few cases of osteomyelitis of the cervical spine caused by pseudomonas aeruginosa have been reported in otherwise healthy patients. This is a case presentation of a young female, who in the absence of known risk factors for cervical osteomyelitis presented with progressively worsening neurological signs and symptoms. PMID:27891039

  7. Construction of a Pseudomonas hybrid strain that mineralizes 2,4,6-trinitrotoluene.

    PubMed Central

    Duque, E; Haidour, A; Godoy, F; Ramos, J L

    1993-01-01

    A bacterium, Pseudomonas sp. strain C1S1, able to grow on 2,4,6-trinitrotoluene (TNT), 2,4- and 2,6-dinitrotoluene, and 2-nitrotoluene as N sources, was isolated. The bacterium grew at 30 degrees C with fructose as a C source and accumulated nitrite. Through batch culture enrichment, we isolated a derivative strain, called Pseudomonas sp. clone A, which grew faster on TNT and did not accumulate nitrite in the culture medium. Use of TNT by these two strains as an N source involved the successive removal of nitro groups to yield 2,4- and 2,6-dinitrotoluene, 2-nitrotoluene, and toluene. Transfer of the Pseudomonas putida TOL plasmid pWW0-Km to Pseudomonas sp. clone A allowed the transconjugant bacteria to grow on TNT as the sole C and N source. All bacteria in this study, in addition to removing nitro groups from TNT, reduced nitro groups on the aromatic ring via hydroxylamine to amino derivatives. Azoxy dimers probably resulting from the condensation of partially reduced TNT derivatives were also found. PMID:8468288

  8. Identification of novel transaminases from a 12-aminododecanoic acid-metabolizing Pseudomonas strain.

    PubMed

    Wilding, Matthew; Walsh, Ellen F A; Dorrian, Susan J; Scott, Colin

    2015-07-01

    A Pseudomonas species [Pseudomonas sp. strain amino alkanoate catabolism (AAC)] was identified that has the capacity to use 12-aminododecanoic acid, the constituent building block of homo-nylon-12, as a sole nitrogen source. Growth of Pseudomonas sp. strain AAC could also be supported using a range of additional ω-amino alkanoates. This metabolic function was shown to be most probably dependent upon one or more transaminases (TAs). Fourteen genes encoding putative TAs were identified from the genome of Pseudomonas sp. AAC. Each of the 14 genes was cloned, 11 of which were successfully expressed in Escherichia coli and tested for activity against 12-aminododecanoic acid. In addition, physiological functions were proposed for 9 of the 14 TAs. Of the 14 proteins, activity was demonstrated in 9, and of note, 3 TAs were shown to be able to catalyse the transfer of the ω-amine from 12-aminododecanoic acid to pyruvate. Based on this study, three enzymes have been identified that are promising biocatalysts for the production of nylon and related polymers.

  9. Isolation of phenazine 1,6-di-carboxylic acid from Pseudomonas aeruginosa strain HRW.1-S3 and its role in biofilm-mediated crude oil degradation and cytotoxicity against bacterial and cancer cells.

    PubMed

    Dasgupta, Debdeep; Kumar, Abhinash; Mukhopadhyay, Balaram; Sengupta, Tapas K

    2015-10-01

    Pseudomonas sp. has long been known for production of a wide range of secondary metabolites during late exponential and stationary phases of growth. Phenazine derivatives constitute a large group of secondary metabolites produced by microorganisms including Pseudomonas sp. Phenazine 1,6-di-carboxylic acid (PDC) is one of such metabolites and has been debated for its origin from Pseudomonas sp. The present study describes purification and characterization of PDC isolated from culture of a natural isolate of Pseudomonas sp. HRW.1-S3 while grown in presence of crude oil as sole carbon source. The isolated PDC was tested for its effect on biofilm formation by another environmental isolate of Pseudomonas sp. DSW.1-S4 which lacks the ability to produce any phenazine compound. PDC showed profound effect on both planktonic as well as biofilm mode of growth of DSW.1-S4 at concentrations between 5 and 20 μM. Interestingly, PDC showed substantial cytotoxicity against three cancer cell lines and against both Gram-positive and Gram-negative bacteria. Thus, the present study not only opens an avenue to understand interspecific cooperation between Pseudomonas species which may lead its applicability in bioremediation, but also it signifies the scope of future investigation on PDC for its therapeutic applications.

  10. Antifungal attributes of siderophore produced by the Pseudomonas aeruginosa JAS-25.

    PubMed

    Sulochana, Mudgulkar Bhimsen; Jayachandra, Sharanappa Yaradoddi; Kumar, Subhash Katti Anil; Dayanand, Agsar

    2014-05-01

    Siderophores produced by Pseudomonas sp. play a vital role in controlling several plant diseases. Public concern about chemical pesticides has fostered an interest to seek alternative control strategies. Production of siderophore by Pseudomonas aeruginosa JAS-25 in King B medium was estimated at 400 nm and was partially purified by gel filtration chromatography using Sephadex G 25. Antifungal activity and inhibition of spore germination was studied against the phytopathogens like Fusarium oxysporum f. sp. ciceri, Fusarium udum, and Aspergillus niger by well plate assay and microphotographic method. Zone of inhibition of 3.0 cm was observed for F. udum and A. niger, proving it as potential biocontrol agent against phytopathogens. Partial 16S rRNA sequence analysis showed that the isolate JAS-25 exhibited 99% homology with P. aeruginosa and could be of novel species and the sequence of the strain was deposited in Genbank with the accession number JX104229.

  11. Various effects of fluorescent bacteria of the genus Pseudomonas containing ACC deaminase on wheat seedling growth.

    PubMed

    Magnucka, Elżbieta G; Pietr, Stanisław J

    2015-12-01

    The study evaluates the effect of rhizobacteria having 1-aminocyclopropane-1-carboxylate deaminase (ACCd) on the development of wheat seedlings. This enzyme has been proposed to play a key role in microbe-plant association. Three fluorescent pseudomonads containing this deaminase were selected from 70 strains of pseudomonads isolated from rhizosphere of wheat (Triticum aestivum L.) and rape (Brassica napus L.). These bacteria, varied significantly in the ability to both biosynthesize auxins and hydrolyze ACC. Among them, Pseudomonas brassicacearum subsp. brassicacearum strain RZ310 presented the highest activities of ACC deaminase during 96h of growth in liquid Dworkin and Foster (DF) salt medium. Additionally, this rape rhizosphere strain did not produce indoles. Two other isolates, Pseudomonas sp. PO283 and Pseudomonas sp. PO366, secreted auxins only in the presence of their precursor. Phylogenetic analysis of the 16S rRNA gene and four other protein-encoding genes indicated that these wheat rhizosphere isolates belonged to the fluorescent Pseudomonas group. Moreover, the effects of these strains on wheat seedling growth under in vitro conditions were markedly dependent on both their cell suspensions used to grain inoculation and nutrient conditions. Strains tested had beneficial influence on wheat seedlings mainly at low cell densities. In addition, access to nutrients markedly changed bacteria action on cereal growth. Their presence generally favored the positive effects of pseudomonads on length and the estimated biomasses of wheat coleoptiles. Despite these general rules, impacts of each isolate on the growth parameters of cereal seedlings were unique.

  12. Hydroxylamine oxidation in heterotrophic nitrate-reducing soil bacteria and purification of a hydroxylamine-cytochrome c oxidoreductase from a Pseudomonas species.

    PubMed

    Wehrfritz, J; Carter, J P; Spiro, S; Richardson, D J

    1996-12-01

    Hydroxylamine oxidation was measured in four recently isolated heterotrophic nitrate-reducing bacteria belonging to the genera Pseudomonas, Moraxella, Arthrobacter and Aeromonas. A hydroxylamine-cytochrome c oxidoreductase activity was detected in periplasmic fractions of the Pseudomonas and Aeromonas spp. and in total soluble fractions of the Arthrobacter sp. A monomeric 19-kDa non-haem iron hydroxylamine-cytochrome c oxidoreductase was purified from the Pseudomonas species and shown to be similar to hydroxylamine-cytochrome c oxidoreductase of Paracoccus denitrificans.

  13. Nosocomial Infections with IMP-19−Producing Pseudomonas aeruginosa Linked to Contaminated Sinks, France

    PubMed Central

    Amoureux, Lucie; Riedweg, Karena; Chapuis, Angélique; Bador, Julien; Siebor, Eliane; Péchinot, André; Chrétien, Marie-Lorraine; de Curraize, Claire

    2017-01-01

    We isolated IMP-19–producing Pseudomonas aeruginosa from 7 patients with nosocomial infections linked to contaminated sinks in France. We showed that blaIMP-19 was located on various class 1 integrons among 8 species of gram-negative bacilli detected in sinks: P. aeruginosa, Achromobacter xylosoxidans, A. aegrifaciens, P. putida, Stenotrophomonas maltophilia, P. mendocina, Comamonas testosteroni, and Sphingomonas sp. PMID:28098548

  14. Genetic Lineages and Antimicrobial Resistance in Pseudomonas spp. Isolates Recovered from Food Samples.

    PubMed

    Estepa, Vanesa; Rojo-Bezares, Beatriz; Torres, Carmen; Sáenz, Yolanda

    2015-06-01

    Raw food is a reservoir of Pseudomonas isolates that could be disseminated to consumers. The presence of Pseudomonas spp. was studied in food samples, and the phenotypic and genotypic characterizations of the recovered isolates were analyzed. Two samples of meat (3%, turkey and beef) and 13 of vegetables (22%, 7 green peppers and 6 tomatoes) contained Pseudomonas spp. A total of 20 isolates were identified, and were classified as follows (number of isolates): P. aeruginosa (5), P. putida (5), P. nitroreducens (4), P. fulva (2), P. mosselli (1), P. mendocina (1), P. monteilii (1), and Pseudomonas sp. (1). These 20 Pseudomonas isolates were clonally different by pulsed-field-gel-electrophoresis, and were resistant to the following antibiotics: ticarcillin (85%), aztreonam (30%), cefepime (10%), imipenem (10%), and meropenem (5%), but were susceptible to ceftazidime, piperacillin, piperacillin-tazobactam, doripenem, gentamicin, tobramycin, amikacin, ciprofloxacin, norfloxacin, and colistin. Only one strain (Ps158) presented a class 1 integron lacking the 3' conserved segment. The five P. aeruginosa strains were typed by multilocus sequence typing in five different sequence-types (ST17, ST270, ST800, ST1455, and ST1456), and different mutations were detected in protein OprD that were classified in three groups. One strain (Ps159) showed a new insertion sequence (ISPa47) truncating the oprD gene, and conferring resistance to imipenem.

  15. Sustainable production of valuable compound 3-succinoyl-pyridine by genetically engineering Pseudomonas putida using the tobacco waste.

    PubMed

    Wang, Weiwei; Xu, Ping; Tang, Hongzhi

    2015-11-17

    Treatment of solid and liquid tobacco wastes with high nicotine content remains a longstanding challenge. Here, we explored an environmentally friendly approach to replace tobacco waste disposal with resource recovery by genetically engineering Pseudomonas putida. The biosynthesis of 3-succinoyl-pyridine (SP), a precursor in the production of hypotensive agents, from the tobacco waste was developed using whole cells of the engineered Pseudomonas strain, S16dspm. Under optimal conditions in fed-batch biotransformation, the final concentrations of product SP reached 9.8 g/L and 8.9 g/L from aqueous nicotine solution and crude suspension of the tobacco waste, respectively. In addition, the crystal compound SP produced from aqueous nicotine of the tobacco waste in batch biotransformation was of high purity and its isolation yield on nicotine was 54.2%. This study shows a promising route for processing environmental wastes as raw materials in order to produce valuable compounds.

  16. Sustainable production of valuable compound 3-succinoyl-pyridine by genetically engineering Pseudomonas putida using the tobacco waste

    PubMed Central

    Wang, Weiwei; Xu, Ping; Tang, Hongzhi

    2015-01-01

    Treatment of solid and liquid tobacco wastes with high nicotine content remains a longstanding challenge. Here, we explored an environmentally friendly approach to replace tobacco waste disposal with resource recovery by genetically engineering Pseudomonas putida. The biosynthesis of 3-succinoyl-pyridine (SP), a precursor in the production of hypotensive agents, from the tobacco waste was developed using whole cells of the engineered Pseudomonas strain, S16dspm. Under optimal conditions in fed-batch biotransformation, the final concentrations of product SP reached 9.8 g/L and 8.9 g/L from aqueous nicotine solution and crude suspension of the tobacco waste, respectively. In addition, the crystal compound SP produced from aqueous nicotine of the tobacco waste in batch biotransformation was of high purity and its isolation yield on nicotine was 54.2%. This study shows a promising route for processing environmental wastes as raw materials in order to produce valuable compounds. PMID:26574178

  17. [Plasmid P85 from Azospirillum brasilense SP245: study of the circle of possible hosts and incompatibility with plasmids from Azospirillum brasilense SP7].

    PubMed

    Katsy, E I

    1992-01-01

    The possibility of the stable inheritance of the plasmid p85 mobilized derivatives from Azospirillum brasilense Sp245 in the cells of the bacterial genera Rizobiaceae (Agrobacterium tumfaciens) and Pseudomonadaceae (Pseudomonas putida) has been shown. The plasmid p85 participates in coding for the physiologically active products (the plant hormones). It is not inherited by the Escherichia coli strains. For the first time the incompatibility of azospirillium plasmids has been demonstrated on the example of the plasmid p85 from Azospirillum brasilense Sp245 and the plasmid p115 from Azospirillum brasilense Sp7.

  18. Cyanide production by Pseudomonas fluorescens and Pseudomonas aeruginosa.

    PubMed Central

    Askeland, R A; Morrison, S M

    1983-01-01

    Of 200 water isolates screened, five strains of Pseudomonas fluorescens and one strain of Pseudomonas aeruginosa were cyanogenic. Maximum cyanogenesis by two strains of P. fluorescens in a defined growth medium occurred at 25 to 30 degrees C over a pH range of 6.6 to 8.9. Cyanide production per cell was optimum at 300 mM phosphate. A linear relationship was observed between cyanogenesis and the log of iron concentration over a range of 3 to 300 microM. The maximum rate of cyanide production occurred during the transition from exponential to stationary growth phase. Radioactive tracer experiments with [1-14C]glycine and [2-14C]glycine demonstrated that the cyanide carbon originates from the number 2 carbon of glycine for both P. fluorescens and P. aeruginosa. Cyanide production was not observed in raw industrial wastewater or in sterile wastewater inoculated with pure cultures of cyanogenic Pseudomonas strains. Cyanide was produced when wastewater was amended by the addition of components of the defined growth medium. PMID:6410989

  19. Cyanide production by Pseudomonas fluorescens and Pseudomonas aeruginosa.

    PubMed

    Askeland, R A; Morrison, S M

    1983-06-01

    Of 200 water isolates screened, five strains of Pseudomonas fluorescens and one strain of Pseudomonas aeruginosa were cyanogenic. Maximum cyanogenesis by two strains of P. fluorescens in a defined growth medium occurred at 25 to 30 degrees C over a pH range of 6.6 to 8.9. Cyanide production per cell was optimum at 300 mM phosphate. A linear relationship was observed between cyanogenesis and the log of iron concentration over a range of 3 to 300 microM. The maximum rate of cyanide production occurred during the transition from exponential to stationary growth phase. Radioactive tracer experiments with [1-14C]glycine and [2-14C]glycine demonstrated that the cyanide carbon originates from the number 2 carbon of glycine for both P. fluorescens and P. aeruginosa. Cyanide production was not observed in raw industrial wastewater or in sterile wastewater inoculated with pure cultures of cyanogenic Pseudomonas strains. Cyanide was produced when wastewater was amended by the addition of components of the defined growth medium.

  20. LACTIC DEHYDROGENASES OF PSEUDOMONAS NATRIEGENS.

    PubMed

    WALKER, H; EAGON, R G

    1964-07-01

    Walker, Hazel (University of Georgia, Athens), and R. G. Eagon. Lactic dehydrogenases of Pseudomonas natriegens. J. Bacteriol. 88:25-30. 1964.-Lactic dehydrogenases specific for d- and l-lactate were demonstrated in Pseudomonas natriegens. The l-lactic dehydrogenase showed considerable heat stability, and 40% of the activity remained in extracts after heating at 60 C for 10 min. An essential thiol group for enzyme activity was noted. The results of these experiments were consistent with the view that lactate was dehydrogenated initially by a flavin cofactor and that electrons were transported through a complete terminal oxidase system to oxygen. The intracellular site of these lactic dehydrogenases was shown to be the cell membrane. It was suggested that the main physiological role of these lactic dehydrogenases is that of lactate utilization.

  1. Engineering Pseudomonas fluorescens for Biodegradation of 2,4-Dinitrotoluene†

    PubMed Central

    Monti, Mariela R.; Smania, Andrea M.; Fabro, Georgina; Alvarez, María E.; Argaraña, Carlos E.

    2005-01-01

    Using the genes encoding the 2,4-dinitrotoluene degradation pathway enzymes, the nonpathogenic psychrotolerant rhizobacterium Pseudomonas fluorescens ATCC 17400 was genetically modified for degradation of this priority pollutant. First, a recombinant strain designated MP was constructed by conjugative transfer from Burkholderia sp. strain DNT of the pJS1 megaplasmid, which contains the dnt genes for 2,4-dinitrotoluene degradation. This strain was able to grow on 2,4-dinitrotoluene as the sole source of carbon, nitrogen, and energy at levels equivalent to those of Burkholderia sp. strain DNT. Nevertheless, loss of the 2,4-dinitrotoluene degradative phenotype was observed for strains carrying pJS1. The introduction of dnt genes into the P.fluorescens ATCC 17400 chromosome, using a suicide chromosomal integration Tn5-based delivery plasmid system, generated a degrading strain that was stable for a long time, which was designated RE. This strain was able to use 2,4-dinitrotoluene as a sole nitrogen source and to completely degrade this compound as a cosubstrate. Furthermore, P. fluorescens RE, but not Burkholderia sp. strain DNT, was capable of degrading 2,4-dinitrotoluene at temperatures as low as 10°C. Finally, the presence of P. fluorescens RE in soils containing levels of 2,4-dinitrotoluene lethal to plants significantly decreased the toxic effects of this nitro compound on Arabidopsis thaliana growth. Using synthetic medium culture, P. fluorescens RE was found to be nontoxic for A.thaliana and Nicotiana tabacum, whereas under these conditions Burkholderia sp. strain DNT inhibited A.thaliana seed germination and was lethal to plants. These features reinforce the advantageous environmental robustness of P. fluorescens RE compared with Burkholderia sp. strain DNT. PMID:16332883

  2. Phosphate taxis in Pseudomonas aeruginosa.

    PubMed

    Kato, J; Ito, A; Nikata, T; Ohtake, H

    1992-08-01

    Pseudomonas aeruginosa was shown to be attracted to phosphate. The chemotactic response was induced by phosphate starvation. The specificity of chemoreceptors for phosphate was high so that no other tested phosphorus compounds elicited a chemotactic response as strong as that elicited by phosphate. Competition experiments showed that the chemoreceptors for phosphate appeared to be different from those for the common amino acids. Mutants constitutive for alkaline phosphatase showed the chemotactic response to phosphate regardless of whether the cells were starved for phosphate.

  3. Biosynthesis, Chemical Structure, and Structure-Activity Relationship of Orfamide Lipopeptides Produced by Pseudomonas protegens and Related Species

    PubMed Central

    Ma, Zongwang; Geudens, Niels; Kieu, Nam P.; Sinnaeve, Davy; Ongena, Marc; Martins, José C.; Höfte, Monica

    2016-01-01

    Orfamide-type cyclic lipopeptides (CLPs) are biosurfactants produced by Pseudomonas and involved in lysis of oomycete zoospores, biocontrol of Rhizoctonia and insecticidal activity against aphids. In this study, we compared the biosynthesis, structural diversity, in vitro and in planta activities of orfamides produced by rhizosphere-derived Pseudomonas protegens and related Pseudomonas species. Genetic characterization together with chemical identification revealed that the main orfamide compound produced by the P. protegens group is orfamide A, while the related strains Pseudomonas sp. CMR5c and CMR12a produce orfamide B. Comparison of orfamide fingerprints led to the discovery of two new orfamide homologs (orfamide F and orfamide G) in Pseudomonas sp. CMR5c. The structures of these two CLPs were determined by nuclear magnetic resonance (NMR) and mass spectrometry (MS) analysis. Mutagenesis and complementation showed that orfamides determine the swarming motility of parental Pseudomonas sp. strain CMR5c and their production was regulated by luxR type regulators. Orfamide A and orfamide B differ only in the identity of a single amino acid, while orfamide B and orfamide G share the same amino acid sequence but differ in length of the fatty acid part. The biological activities of orfamide A, orfamide B, and orfamide G were compared in further bioassays. The three compounds were equally active against Magnaporthe oryzae on rice, against Rhizoctonia solani AG 4-HGI in in vitro assays, and caused zoospore lysis of Phytophthora and Pythium. Furthermore, we could show that orfamides decrease blast severity in rice plants by blocking appressorium formation in M. oryzae. Taken all together, our study shows that orfamides produced by P. protegens and related species have potential in biological control of a broad spectrum of fungal plant pathogens. PMID:27065956

  4. Effect of Iron Availability on Induction of Systemic Resistance to Fusarium Wilt of Chickpea by Pseudomonas spp.

    PubMed

    Saikia, Ratul; Srivastava, Alok K; Singh, Kiran; Arora, Dilip K; Lee, Min-Woong

    2005-03-01

    Selected isolates of Pseudomonas fluorescens (Pf4-92 and PfRsC5) and P. aeruginosa (PaRsG18 and PaRsG27) were examined for growth promotion and induced systemic resistance against Fusarium wilt of chickpea. Significant increase in plant height was observed in Pseudomonas treated plants. However, plant growth was inhibited when isolates of Pseudomonas were used in combination with Fusarium oxysporum f. sp. ciceri (FocRs1). It was also observed that the Pseudomonas spp. was colonized in root of chickpea and significantly suppressed the disease in greenhouse condition. Rock wool bioassay technique was used to study the effect of iron availability on the induction of systemic resistance to Fusarium wilt of chickpea mediated by the Pseudomonas spp. All the isolates of Pseudomonas spp. showed greater disease control in the induced systemic resistance (ISR) bioassay when iron availability in the nutrient solution was low. High performance liquid chromatography (HPLC) analysis indicated that all the bacterial isolates produced more salicylic acid (SA) at low iron (10µM EDDHA) than high iron availability (10µFe(3+) EDDHA). Except PaRsG27, all the three isolates produced more pseudobactin at low iron than high iron availability.

  5. Actinobacteria Associated with the Marine Sponges Cinachyra sp., Petrosia sp., and Ulosa sp. and Their Culturability

    PubMed Central

    Khan, Shams Tabrez; Takagi, Motoki; Shin-ya, Kazuo

    2012-01-01

    Actinobacteria associated with 3 marine sponges, Cinachyra sp., Petrosia sp., and Ulosa sp., were investigated. Analyses of 16S rRNA gene clone libraries revealed that actinobacterial diversity varied greatly and that Ulosa sp. was most diverse, while Cinachyra sp. was least diverse. Culture-based approaches failed to isolate actinobacteria from Petrosia sp. or Ulosa sp., but strains belonging to 10 different genera and 3 novel species were isolated from Cinachyra sp. PMID:22214828

  6. Degradation of Alkyl Benzene Sulfonate by Pseudomonas Species1

    PubMed Central

    Horvath, R. S.; Koft, B. W.

    1972-01-01

    Pseudomonas sp. HK-1 showed a direct relation between the concentration of alkyl benzene sulfonate (ABS) supplied and cell yields. Since growth on ABS alone did not occur, it was necessary to correlate the total energy obtained by the cells to the ABS concentration when glucose was supplied in a limiting concentration. Several types of metabolic attack in addition to the sulfonate removal were noted: (i) side-chain utilization as indicated by the production of tertiarybutyl alcohol and isopropanol and (ii) ring metabolism as indicated by the presence of phenol, catechol, mandelic acid, benzyl alcohol, and benzoic acid in spent growth media. Utilization of ABS was greatly enhanced by the presence of phenol. This enhancement suggests co-metabolism and that limited concentrations of phenolic products derived from ABS must be accumulated to get active metabolism of the ABS molecule. PMID:5017680

  7. Genomics of Secondary Metabolism in Pseudomonas spp.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pseudomonas is a heterogeneous genus of bacteria known for its ubiquity in natural habitats and its prolific production of secondary metabolites. The structurally diverse chemical structures produced by Pseudomonas spp. result from biosynthetic processes with unusual features that have revealed no...

  8. Pseudomonas blight discovered on raspberry in Watsonville

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the winter (February) of 2013, a field of raspberries in Watsonville was discovered to be infected with Pseudomonas syringae, the causal agent of Pseudomonas blight disease. This was the first documentation of this disease on raspberry in our region. The infection of raspberry plants is manifeste...

  9. Complex marine natural products as potential epigenetic and production regulators of antibiotics from a marine Pseudomonas aeruginosa.

    PubMed

    Wang, Bin; Waters, Amanda L; Sims, James W; Fullmer, Alexis; Ellison, Serena; Hamann, Mark T

    2013-05-01

    Marine microbes are capable of producing secondary metabolites for defense and competition. Factors exerting an impact on secondary metabolite production of microbial communities included bioactive natural products and co-culturing. These external influences may have practical applications such as increased yields or the generation of new metabolites from otherwise silent genes in addition to reducing or limiting the production of undesirable metabolites. In this paper, we discuss the metabolic profiles of a marine Pseudomonas aeruginosa in the presence of a number of potential chemical epigenetic regulators, adjusting carbon sources and co-culturing with other microbes to induce a competitive response. As a result of these stressors certain groups of antibiotics or antimalarial agents were increased most notably when treating P. aeruginosa with sceptrin and co-culturing with another Pseudomonas sp. An interesting cross-talking event between these two Pseudomonas species when cultured together and exposed to sceptrin was observed.

  10. Complex marine natural products as potential epigenetic and production regulators of antibiotics from a marine Pseudomonas aeruginosa

    PubMed Central

    Wang, Bin; Waters, Amanda L.; Sims, James W.; Fullmer, Alexis; Ellison, Serena; Hamann, Mark T.

    2013-01-01

    Marine microbes are capable of producing secondary metabolites for defense and competition. Factors exerting an impact on secondary metabolite production of microbial communities included bioactive natural products and co-culturing. These external influences may have practical applications such as increased yields or the generation of new metabolites from otherwise silent genes in addition to reducing or limiting the production of undesirable metabolites. In this paper, we discuss the metabolic profiles of a marine Pseudomonas aeruginosa in the presence of a number of potential chemical epigenetic regulators, adjusting carbon sources and co-culturing with other microbes to induce a competitive response. As a result of these stressors certain groups of antibiotics or antimalarial agents were increased most notably when treating P. aeruginosa with sceptrin and co-culturing with another Pseudomonas sp. An interesting cross-talking event between these two Pseudomonas species when cultured together and exposed to sceptrin was observed. PMID:23563743

  11. Treatment of dairy wastewater using a selected bacterial isolate, Alcaligenes sp. MMRR7.

    PubMed

    Rajeshkumar, K; Jayachandran, K

    2004-01-01

    Physicochemical and biologic analysis of dairy wastewater showed that the effluent had a high organic load (chemical oxygen demand [COD]: 5095 mg/L), an acidic pH (6.4), and a high probability of coliforms (most probable number [MPN] >1100). The various bacterial strains isolated and purified were identified as Sporolactobacillus sp., Citrobacter sp., Pseudomonas sp., Alcaligenes sp., Bacillus sp., Staphylococcus sp., and Proteus sp., as per the Bergey's manual of systematic bacteriology. Among the five selected bacterial strains, the strain designated as MMRR7 and identified as Alcaligenes sp. was found to give a maximum reduction in COD (62%) in 5 d of incubation. Chemical coagulation using alum at a concentration of 0.5 g/100 mL was found to be effective in the primary treatment of the effluent. Studies on free-cell treatment of the coagulated effluent with the selected bacterial strain Alcaligenes sp. MMRR7 gave a maximum COD reduction of 91% in 120 h. This study clearly indicates the possibility of using Alcaligenes sp. MMRR7 for the effective treatment of dairy wastewater.

  12. Regulation of Pseudomonas quinolone signal synthesis in Pseudomonas aeruginosa.

    PubMed

    Wade, Dana S; Calfee, M Worth; Rocha, Edson R; Ling, Elizabeth A; Engstrom, Elana; Coleman, James P; Pesci, Everett C

    2005-07-01

    Pseudomonas aeruginosa is an opportunistic pathogen that causes chronic lung infections in cystic fibrosis patients and is a major source of nosocomial infections. This bacterium controls many virulence factors by using two quorum-sensing systems, las and rhl. The las system is composed of the LasR regulator protein and its cell-to-cell signal, N-(3-oxododecanoyl) homoserine lactone, and the rhl system is composed of RhlR and the signal N-butyryl homoserine lactone. A third intercellular signal, the Pseudomonas quinolone signal (PQS; 2-heptyl-3-hydroxy-4-quinolone), also regulates numerous virulence factors. PQS synthesis requires the expression of multiple operons, one of which is pqsABCDE. Previous experiments showed that the transcription of this operon, and therefore PQS production, is negatively regulated by the rhl quorum-sensing system and positively regulated by the las quorum-sensing system and PqsR (also known as MvfR), a LysR-type transcriptional regulator protein. With the use of DNA mobility shift assays and beta-galactosidase reporter fusions, we have studied the regulation of pqsR and its relationship to pqsA, lasR, and rhlR. We show that PqsR binds the promoter of pqsA and that this binding increases dramatically in the presence of PQS, implying that PQS acts as a coinducer for PqsR. We have also mapped the transcriptional start site for pqsR and found that the transcription of pqsR is positively regulated by lasR and negatively regulated by rhlR. These results suggest that a regulatory chain occurs where pqsR is under the control of LasR and RhlR and where PqsR in turn controls pqsABCDE, which is required for the production of PQS.

  13. Degradation of 3-Phenoxybenzoic Acid in Soil by Pseudomonas pseudoalcaligenes POB310(pPOB) and Two Modified Pseudomonas Strains

    PubMed Central

    Halden, Rolf U.; Tepp, Sandra M.; Halden, Barbara G.; Dwyer, Daryl F.

    1999-01-01

    Pseudomonas pseudoalcaligenes POB310(pPOB) and Pseudomonas sp. strains B13-D5(pD30.9) and B13-ST1(pPOB) were introduced into soil microcosms containing 3-phenoxybenzoic acid (3-POB) in order to evaluate and compare bacterial survival, degradation of 3-POB, and transfer of plasmids to a recipient bacterium. Strain POB310 was isolated for its ability to use 3-POB as a growth substrate; degradation is initiated by POB-dioxygenase, an enzyme encoded on pPOB. Strain B13-D5 contains pD30.9, a cloning vector harboring the genes encoding POB-dioxygenase; strain B13-ST1 contains pPOB. Degradation of 3-POB in soil by strain POB310 was incomplete, and bacterial densities decreased even under the most favorable conditions (100 ppm of 3-POB, supplementation with P and N, and soil water-holding capacity of 90%). Strains B13-D5 and B13-ST1 degraded 3-POB (10 to 100 ppm) to concentrations of <50 ppb with concomitant increases in density from 106 to 108 CFU/g (dry weight) of soil. Thus, in contrast to strain POB310, the modified strains had the following two features that are important for in situ bioremediation: survival in soil and growth concurrent with removal of an environmental contaminant. Strains B13-D5 and B13-ST1 also completely degraded 3-POB when the inoculum was only 30 CFU/g (dry weight) of soil. This suggests that in situ bioremediation may be effected, in some cases, with low densities of introduced bacteria. In pure culture, transfer of pPOB from strains POB310 and B13-ST1 to Pseudomonas sp. strain B13 occurred at frequencies of 5 × 10−7 and 10−1 transconjugant per donor, respectively. Transfer of pPOB from strain B13-ST1 to strain B13 was observed in autoclaved soil but not in nonautoclaved soil; formation of transconjugant bacteria was more rapid in soil containing clay and organic matter than in sandy soil. Transfer of pPOB from strain POB310 to strain B13 in soil was never observed. PMID:10427019

  14. [Pseudomonas genus bacteria on weeds].

    PubMed

    Gvozdiak, R I; Iakovleva, L M; Pasichnik, L A; Shcherbina, T N; Ogorodnik, L E

    2005-01-01

    It has been shown in the work that the weeds (couch-grass and ryegrass) may be affected by bacterial diseases in natural conditions, Pseudomonas genus bacteria being their agents. The isolated bacteria are highly-aggressive in respect of the host-plant and a wide range of cultivated plants: wheat, rye, oats, barley, apple-tree and pear-tree. In contrast to highly aggressive bacteria isolated from the affected weeds, bacteria-epi phytes isolated from formally healthy plants (common amaranth, orache, flat-leaved spurge, field sow thistle, matricary, common coltsfoot, narrow-leaved vetch) and identified as P. syringae pv. coronafaciens, were characterized by weak aggression. A wide range of ecological niches of bacteria evidently promote their revival and distribution everywhere in nature.

  15. Ice crystallization by Pseudomonas syringae.

    PubMed

    Cochet, N; Widehem, P

    2000-08-01

    Several bacterial species can serve as biological ice nuclei. The best characterized of these is Pseudomonas syringae, a widely distributed bacterial epiphyte of plants. These biological ice nuclei find various applications in different fields, but an optimized production method was required in order to obtain the highly active cells which may be exploited as ice nucleators. The results presented here show that P. syringae cells reduce supercooling of liquid or solid media and enhance ice crystal formation at sub-zero temperatures, thus leading to a remarkable control of the crystallization phenomenon and a potential for energy savings. Our discussion focuses on recent and future applications of these ice nucleators in freezing operations, spray-ice technology and biotechnological processes.

  16. [Pneumonia due to Pseudomonas aeruginosa].

    PubMed

    Vallés, Jordi; Mariscal, Dolors

    2005-12-01

    Pseudomonas aeruginosa is one of the leading causes of Gram-negative nosocomial pneumonia. It is the most common cause of ventilator-associated pneumonia and carries the highest mortality among hospital-acquired infections. P. aeruginosa produces a large number of toxins and surface components that make it especially virulent compared with other microorganisms. These include pili, flagella, membrane bound lipopolysaccharide, and secreted products such as exotoxins A, S and U, elastase, alkaline protease, cytotoxins and phospholipases. The most common mechanism of infection in mechanically ventilated patients is through aspiration of upper respiratory tract secretions previously colonized in the process of routine nursing care or via contaminated hands of hospital personnel. Intravenous therapy with an antipseudomonal regimen should be started immediately when P. aeruginosa pneumonia is suspected or confirmed. Empiric therapy with drugs active against P. aeruginosa should be started, especially in patients who have received previous antibiotics or present late-onset pneumonia.

  17. Tolerance to creosote oil of bacteria of the genus Pseudomonas isolated from the wood of coniferous trees.

    PubMed

    Gajewska, Julitta; Miszczyk, Anita; Markiewicz, Zdzisław

    2003-01-01

    A number of Pseudomonas sp. strains isolated from wood shavings not preserved with chemical agents were characterized by tolerance to concentrated creosote oil. Of eleven strains subjected to closer scrutiny, five showed good or very good growth in minimal medium with creosote oil as sole carbon and energy source. These isolates can be of potential use for the biodegradation of waste wood conserved with creosote oil.

  18. In vitro activity of moxalactam and mecillinam, singly and in combination, against multi-drug-resistant Enterobacteriaceae and Pseudomonas species.

    PubMed Central

    Fass, R J

    1982-01-01

    The in vitro interaction of moxalactam and mecillinam against multi-drug-resistant gram-negative enteric bacilli was studied by checkerboard microdilution susceptibility tests and by killing curve kinetics. Against Enterobacteriaceae, the combination was unpredictable; the frequencies of synergy, indifference, and antagonism were 11, 76, and 13%, respectively. Against Pseudomonas sp., the two drugs were consistently indifferent. Overall, the combination of moxalactam and mecillinam was no more active than moxalactam alone. PMID:6282206

  19. Resistance to Fusarium oxysporum f. sp. gladioli in transgenic Gladiolus plants expressing either a bacterial chloroperoxidase or fungal chitinase genes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Three antifungal genes, a non-heme chloroperoxidase from Pseudomonas pyrrocinia, and an exochitinase and endochitinase from Fusarium venetanum under regulation by the CaMV 35S promoter, were used to transform Gladiolus for resistance to Fusarium oxysporum f. sp. gladioli. Gladiolus plants were conf...

  20. Protozoan growth rates on secondary-metabolite-producing Pseudomonas spp. correlate with high-level protozoan taxonomy.

    PubMed

    Pedersen, Annette L; Winding, Anne; Altenburger, Andreas; Ekelund, Flemming

    2011-03-01

    Different features can protect bacteria against protozoan grazing, for example large size, rapid movement, and production of secondary metabolites. Most papers dealing with these matters focus on bacteria. Here, we describe protozoan features that affect their ability to grow on secondary-metabolite-producing bacteria, and examine whether different bacterial secondary metabolites affect protozoa similarly. We investigated the growth of nine different soil protozoa on six different Pseudomonas strains, including the four secondary-metabolite-producing Pseudomonas fluorescens DR54 and CHA0, Pseudomonas chlororaphis MA342 and Pseudomonas sp. DSS73, as well as the two nonproducers P. fluorescens DSM50090(T) and P. chlororaphis ATCC43928. Secondary metabolite producers affected protozoan growth differently. In particular, bacteria with extracellular secondary metabolites seemed more inhibiting than bacteria with membrane-bound metabolites. Interestingly, protozoan response seemed to correlate with high-level protozoan taxonomy, and amoeboid taxa tolerated a broader range of Pseudomonas strains than did the non-amoeboid taxa. This stresses the importance of studying both protozoan and bacterial characteristics in order to understand bacterial defence mechanisms and potentially improve survival of bacteria introduced into the environment, for example for biocontrol purposes.

  1. Pseudomonas cichorii as the causal agent of midrib rot, an emerging disease of greenhouse-grown butterhead lettuce in Flanders.

    PubMed

    Cottyn, Bart; Heylen, Kim; Heyrman, Jeroen; Vanhouteghem, Katrien; Pauwelyn, Ellen; Bleyaert, Peter; Van Vaerenbergh, Johan; Höfte, Monica; De Vos, Paul; Maes, Martine

    2009-05-01

    Bacterial midrib rot of greenhouse-grown butterhead lettuce (Lactuca sativa L. var. capitata) is an emerging disease in Flanders (Belgium) and fluorescent pseudomonads are suspected to play an important role in the disease. Isolations from infected lettuces, collected from 14 commercial greenhouses in Flanders, yielded 149 isolates that were characterized polyphasically, which included morphological characteristics, pigmentation, pathogenicity tests by both injection and spraying of lettuce, LOPAT characteristics, FAME analysis, BOX-PCR fingerprinting, 16S rRNA and rpoB gene sequencing, as well as DNA-DNA hybridization. Ninety-eight isolates (66%) exhibited a fluorescent pigmentation and were associated with the genus Pseudomonas. Fifty-five of them induced an HR+ (hypersensitive reaction in tobacco leaves) response. The other 43 fluorescent isolates were most probably saprophytic bacteria and about half of them were able to cause rot on potato tuber slices. BOX-PCR genomic fingerprinting was used to assess the genetic diversity of the Pseudomonas midrib rot isolates. The delineated BOX-PCR patterns matched quite well with Pseudomonas morphotypes defined on the basis of colony appearance and variation in fluorescent pigmentation. 16S rRNA and rpoB gene sequence analyses allowed most of the fluorescent isolates to be allocated to Pseudomonas, and they belonged to either the Pseudomonas fluorescens group, Pseudomonas putida group, or the Pseudomonas cichorii/syringae group. In particular, the isolates allocated to this latter group constituted the vast majority of HR+ isolates and were identified as P. cichorii by DNA-DNA hybridization. They were demonstrated by spray-inoculation tests on greenhouse-grown lettuce to induce the midrib rot disease and could be re-isolated from lesions of inoculated plants. Four HR+ non-fluorescent isolates associated with one sample that showed an atypical midrib rot were identified as Dickeya sp.

  2. Antibiotic Conditioned Growth Medium of Pseudomonas Aeruginosa

    ERIC Educational Resources Information Center

    Benathen, Isaiah A.; Cazeau, Barbara; Joseph, Njeri

    2004-01-01

    A simple method to study the consequences of bacterial antibiosis after interspecific competition between microorganisms is presented. Common microorganisms are used as the test organisms and Pseudomonas aeruginosa are used as the source of the inhibitor agents.

  3. Actinobacillus rossii sp. nov., Actinobacillus seminis sp. nov., nom. rev., Pasteurella bettii sp. nov., Pasteurella lymphangitidis sp. nov., Pasteurella mairi sp. nov., and Pasteurella trehalosi sp. nov.

    PubMed

    Sneath, P H; Stevens, M

    1990-04-01

    Evidence from numerical taxonomic analysis and DNA-DNA hybridization supports the proposal of new species in the genera Actinobacillus and Pasteurella. The following new species are proposed: Actinobacillus rossii sp. nov., from the vaginas of postparturient sows; Actinobacillus seminis sp. nov., nom. rev., associated with epididymitis of sheep; Pasteurella bettii sp. nov., associated with human Bartholin gland abscess and finger infections; Pasteurella lymphangitidis sp. nov. (the BLG group), which causes bovine lymphangitis; Pasteurella mairi sp. nov., which causes abortion in sows; and Pasteurella trehalosi sp. nov., formerly biovar T of Pasteurella haemolytica, which causes septicemia in older lambs.

  4. Characterization of organophosphorus hydrolases and the genetic manipulation of the phosphotriesterase from pseudomonas diminuta

    SciTech Connect

    Dave, K.I.; Miller, C.E.; Wild, J.R.

    1993-12-31

    There are a variety of enzymes which are specifically capable of hydrolyzing organophosphorus esters with different phosphoryl bonds from the typical phosphotriester bonds of common insecticidal neurotoxins (e.g. paraoxon or coumaphos) to the phosphonate-fluoride bonds of chemical warfare agents (e.g. soman or sarin). These enzymes comprise a diverse set of enzymes whose basic architecture and substrate specificities vary dramatically, yet they appear to be ubiquitous throughout nature. The most thoroughly studied of these enzymes is the organophosphate hydrolase (opd gene product) of Pseudomonas diminuta and Ftavobacterium sp. ATCC 27551, and the heterologous expression, post-translational modification, and genetic engineering studies undertaken with this enzyme are described.

  5. Characterization of organophosphorus hydrolases and the genetic manipulation of the phosphotriesterase from Pseudomonas diminuta.

    PubMed

    Dave, K I; Miller, C E; Wild, J R

    1993-06-01

    There are a variety of enzymes which are specifically capable of hydrolyzing organophosphorus esters with different phosphoryl bonds from the typical phosphotriester bonds of common insecticidal neurotoxins (e.g. paraoxon or coumaphos) to the phosphonate-fluoride bonds of chemical warfare agents (e.g. soman or sarin). These enzymes comprise a diverse set of enzymes whose basic architecture and substrate specificities vary dramatically, yet they appear to be ubiquitous throughout nature. The most thoroughly studied of these enzymes is the organophosphate hydrolase (opd gene product) of Pseudomonas diminuta and Flavobacterium sp. ATCC 27551, and the heterologous expression, post-translational modification, and genetic engineering studies undertaken with this enzyme are described.

  6. Comparison of plant growth-promotion with Pseudomonas aeruginosa and Bacillus subtilis in three vegetables

    PubMed Central

    Adesemoye, A.O.; Obini, M.; Ugoji, E.O.

    2008-01-01

    Our objective was to compare some plant growth promoting rhizobacteria (PGPR) properties of Bacillus subtilis and Pseudomonas aeruginosa as representatives of their two genera. Solanum lycopersicum L. (tomato), Abelmoschus esculentus (okra), and Amaranthus sp. (African spinach) were inoculated with the bacterial cultures. At 60 days after planting, dry biomass for plants treated with B. subtilis and P. aeruginosa increased 31% for tomato, 36% and 29% for okra, and 83% and 40% for African spinach respectively over the non-bacterized control. Considering all the parameters tested, there were similarities but no significant difference at P < 0.05 between the overall performances of the two organisms. PMID:24031240

  7. Pseudomonas aeruginosa: breaking down barriers.

    PubMed

    Berube, Bryan J; Rangel, Stephanie M; Hauser, Alan R

    2016-02-01

    Many bacterial pathogens have evolved ingenious ways to escape from the lung during pneumonia to cause bacteremia. Unfortunately, the clinical consequences of this spread to the bloodstream are frequently dire. It is therefore important to understand the molecular mechanisms used by pathogens to breach the lung barrier. We have recently shown that Pseudomonas aeruginosa, one of the leading causes of hospital-acquired pneumonia, utilizes the type III secretion system effector ExoS to intoxicate pulmonary epithelial cells. Injection of these cells leads to localized disruption of the pulmonary-vascular barrier and dissemination of P. aeruginosa to the bloodstream. We put these data in the context of previous studies to provide a holistic model of P. aeruginosa dissemination from the lung. Finally, we compare P. aeruginosa dissemination to that of other bacteria to highlight the complexity of bacterial pneumonia. Although respiratory pathogens use distinct and intricate strategies to escape from the lungs, a thorough understanding of these processes can lay the foundation for new therapeutic approaches for bacterial pneumonia.

  8. Carbenicillin resistance of Pseudomonas aeruginosa.

    PubMed Central

    Rodríguez-Tebar, A; Rojo, F; Dámaso, D; Vázquez, D

    1982-01-01

    Four strains of Pseudomonas aeruginosa obtained from clinical isolates which are carbenicillin resistant were studied to find the cause(s) of resistance to this beta-lactam antibiotic. The electrophoresis patterns of the four strains (PH20610, PH20815, PH4011, and PH4301) were found to be different from those of a wild-type strain, P. aeruginosa NCTC 10662, and appeared to lack penicillin-binding protein 2. Affinity of other penicillin-binding proteins from strains PH20610 and PH20815 for carbenicillin seemed to be normal or slightly diminished. Electrophoretic patterns of penicillin-binding proteins from strains PH4011 and PH4301 had more profound differences, since the affinities of their penicillin-binding proteins 1a, 1b, and 4 for carbenicillin were decreased by nearly two orders of magnitude relative to the preparations from the wild-type strain. Kinetic studies on binding of carbenicillin to penicillin-binding proteins both in isolated membrane preparations and in intact cells revealed that carbenicillin penetration into resistant cells was a much slower process than in susceptible cells, suggesting that the outer envelope structures serve as an efficient barrier against carbenicillin entry into our P. aeruginosa strains from clinical isolates. PMID:6821456

  9. Novel organization of catechol meta pathway genes in the nitrobenzene degrader Comamonas sp. JS765 and its evolutionary implication.

    PubMed

    He, Zhongqi; Parales, Rebecca E; Spain, Jim C; Johnson, Glenn R

    2007-02-01

    The catechol meta cleavage pathway is one of the central metabolic pathways for the degradation of aromatic compounds. A novel organization of the pathway genes, different from that of classical soil microorganisms, has been observed in Sphingomonas sp HV3 and Pseudomonas sp. DJ77. In a Comamonas sp. JS765, cdoE encoding catechol 2,3-dioxygenase shares a common ancestry only with tdnC of a Pseudomonas putida strain, while codG encoding 2-hydroxymuconic semialdehyde dehydrogenase shows a higher degree of similarity to those genes in classical bacteria. Located between cdoE and cdoG are several putative genes, whose functions are unknown. These genes are not found in meta pathway operons of other microorganisms with the exception of cdoX2, which is similar to cmpX in strain HV3. Therefore, the gene cluster in JS765 reveals a third type of gene organization of the meta pathway.

  10. Analysis of preference for carbon source utilization among three strains of aromatic compounds degrading Pseudomonas.

    PubMed

    Karishma, M; Trivedi, Vikas D; Choudhary, Alpa; Mhatre, Akanksha; Kambli, Pranita; Desai, Jinal; Phale, Prashant S

    2015-10-01

    Soil isolates Pseudomonas putida CSV86, Pseudomonas aeruginosa PP4 and Pseudomonas sp. C5pp degrade naphthalene, phthalate isomers and carbaryl, respectively. Strain CSV86 displayed a diauxic growth pattern on phenylpropanoid compounds (veratraldehyde, ferulic acid, vanillin or vanillic acid) plus glucose with a distinct second lag-phase. The glucose concentration in the medium remained constant with higher cell respiration rates on aromatics and maximum protocatechuate 3,4-dioxygenase activity in the first log-phase, which gradually decreased in the second log-phase with concomitant depletion of the glucose. In strains PP4 and C5pp, growth profile and metabolic studies suggest that glucose is utilized in the first log-phase with the repression of utilization of aromatics (phthalate or carbaryl). All three strains utilize benzoate via the catechol 'ortho' ring-cleavage pathway. On benzoate plus glucose, strain CSV86 showed preference for benzoate over glucose in contrast to strains PP4 and C5pp. Additionally, organic acids like succinate were preferred over aromatics in strains PP4 and C5pp, whereas strain CSV86 co-metabolizes them. Preferential utilization of aromatics over glucose and co-metabolism of organic acids and aromatics are found to be unique properties of P. putida CSV86 as compared with strains PP4 and C5pp and this property of strain CSV86 can be exploited for effective bioremediation.

  11. Novel Lectin-Like Bacteriocins of Biocontrol Strain Pseudomonas fluorescens Pf-5

    PubMed Central

    Parret, Annabel H. A.; Temmerman, Koen; De Mot, René

    2005-01-01

    Bacteriocin LlpA, produced by Pseudomonas sp. strain BW11M1, is a peculiar antibacterial protein due to its homology to mannose-binding lectins mostly found in monocots (A. H. A. Parret, G. Schoofs, P. Proost, and R. De Mot, J. Bacteriol. 185:897-908, 2003). Biocontrol strain Pseudomonas fluorescens Pf-5 contains two llpA-like genes, named llpA1Pf-5 and llpA2Pf-5. Recombinant Escherichia coli cells expressing llpA1Pf-5 or llpA2Pf-5 acquired bacteriocin activity and secreted a 31-kDa protein cross-reacting with LlpABW11M1 antibodies. Antibacterial activity of the recombinant proteins was evidenced by gel overlay assays. Analysis of the antimicrobial spectrum indicated that LlpA1Pf-5 and LlpA2Pf-5 are able to inhibit P. fluorescens strains, as well as the related mushroom pathogen Pseudomonas tolaasii. LlpA-type bacteriocins are characterized by a domain structure consisting of tandem monocot mannose-binding lectin (MMBL) domains. Molecular phylogeny of these MMBL domains suggests that the individual MMBL domains within an LlpA protein have evolved separately toward a specific, as yet unknown, function or, alternatively, were acquired from different ancestral sources. Our observations are consistent with earlier observations, which hinted that MMBL-like bacteriocins represent a new family of antibacterial proteins, probably with a novel mode of action. PMID:16151105

  12. Specific gonadotropin binding to Pseudomonas maltophilia.

    PubMed

    Richert, N D; Ryan, R J

    1977-03-01

    Binding of 125I-labeled human chorionic gonadotropin to Pseudomonas maltophilia is dependent on time, temperature, and pH and the binding to this procaryotic species is hormone-specific and saturable. The equilibrium dissociation constant is 2.3 X 10(-9) M. There are no cooperative interactions between binding sites (Hill coefficient, 1.05). The number of sites is estimaated as 240 fmol/100 mug of protein. NaCl and KCl, at concentrations from 1 to 10 mM, have no effect on binding. Divalent cations (Mg2+ and Ca2+) and 1 mM EDTA inhibit hormone binding. Binding is destroyed by heat or by treatment with Pronase of alpha-chymotrypsin and is increased by phospholipase C. Binding of the labeled gonadotropin is not observed with other gram-negative organisms--e.g., Escherichia coli, Pseudomonas testosteroni, Pseudomonas aeruginosa, Enterobacter aerogenes, or Enterobacter cloacae.

  13. Comparison of aspartate transcarbamoylase regulation in Pseudomonas alcaligenes and Pseudomonas mendocina.

    PubMed

    Santiago, Manuel F; West, Thomas P

    2003-01-01

    The regulation of aspartate transcarbamoylase activity in cell extracts of Pseudomonas alcaligenes ATCC 14909 and Pseudomonas mendocina ATCC 25411 was compared. Under saturating substrate concentrations, pyrophosphate, CTP, UDP and ADP were highly inhibitory of the P. alcaligenes transcarbamoylase activity while pyrophosphate, UDP, ADP, ATP and GTP were the most effective inhibitors of the P. mendocina transcarbamoylase. By examining transcarbamoylase inhibition by ribonucleotide triphosphates, it was possible to differentiate these species assigned to different DNA homology groups and such an analysis might prove useful in the reclassification of Pseudomonas species.

  14. Repression of common bull sperm flora and in vitro impairment of sperm motility with Pseudomonas aeruginosa introduced by contaminated lubricant.

    PubMed

    Smole, I; Thomann, A; Frey, J; Perreten, V

    2010-08-01

    Semen collected from clinically healthy bulls at an artificial insemination centre was examined for bacterial diversity. While bacteria that are normally present in the common flora of bovine semen were absent, such as Mycoplasma sp., Proteus sp. and Corynebacterium sp., all semen samples contained an unusually high number of Pseudomonas aeruginosa strains. Analysis via pulsed field gel electrophoresis demonstrated that one particular P. aeruginosa strain, present in a sealed bottle of lubricant, was widespread in bull semen. This strain was shown to secrete substances that inhibited both the growth of bacteria constituting the normal bull sperm flora and the motility of spermatozoa in vitro. This study demonstrated that commercially available lubricants might contain bacteria that can spread amongst breeding bulls and affect the quality of semen. Bacteriological controls and species' identification are necessary at several production levels, including lubricants and extenders, to ensure high semen quality and avoid the spread of pathogens.

  15. A new selective medium for isolating Pseudomonas spp. from water.

    PubMed Central

    Krueger, C L; Sheikh, W

    1987-01-01

    A new medium, pseudomonas selective isolation agar, was developed to isolate Pseudomonas spp. from water. It consists of 350 micrograms of nitrofurantoin per ml and 2 micrograms of crystal violet per ml in a nutrient agar base. It is more selective for Pseudomonas spp. than are available commercial media. Its ingredients are inexpensive and readily available, and it is easy to prepare. PMID:3579287

  16. Comparative Molecular docking analysis of DNA Gyrase subunit A in Pseudomonas aeruginosaPAO1.

    PubMed

    Gupta, Aman; Sharma, Vanashika; Tewari, Ashish Kumar; Surenderkumar, Vipul; Wadhwa, Gulshan; Mathur, Ashwani; Sharma, Sanjeev Kumar; Jain, Chakresh Kumar

    2013-01-01

    Pseudomonas aeruginosa is an opportunistic bacterium known for causing chronic infections in cystic fibrosis and chronic obstructive pulmonary disease (COPD) patients. Recently, several drug targets in Pseudomonas aeruginosa PAO1 have been reported using network biology approaches on the basis of essentiality and topology and further ranked on network measures viz. degree and centrality. Till date no drug/ligand molecule has been reported against this targets.In our work we have identified the ligand /drug molecules, through Orthologous gene mapping against Bacillus subtilis subsp. subtilis str. 168 and performed modelling and docking analysis. From the predicted drug targets in PA PAO1, we selected those drug targets which show statistically significant orthology with a model organism and whose orthologs are present in all the selected drug targets of PA PAO1.Modeling of their structure has been done using I-Tasser web server. Orthologous gene mapping has been performed using Cluster of Orthologs (COGs) and based on orthology; drugs available for Bacillus sp. have been docked with PA PAO1 protein drug targets using MoleGro virtual docker version 4.0.2.Orthologous gene for PA3168 gyrA is BS gyrAfound in Bacillus subtilis subsp. subtilis str. 168. The drugs cited for Bacillus sp. have been docked with PA genes and energy analyses have been made. Based on Orthologous gene mapping andin-silico studies, Nalidixic acid is reported as an effective drug against PA3168 gyrA for the treatment of CF and COPD.

  17. Pseudomonas aeruginosa Population Structure Revisited

    PubMed Central

    Pirnay, Jean-Paul; Bilocq, Florence; Pot, Bruno; Cornelis, Pierre; Zizi, Martin; Van Eldere, Johan; Deschaght, Pieter; Vaneechoutte, Mario; Jennes, Serge; Pitt, Tyrone; De Vos, Daniel

    2009-01-01

    At present there are strong indications that Pseudomonas aeruginosa exhibits an epidemic population structure; clinical isolates are indistinguishable from environmental isolates, and they do not exhibit a specific (disease) habitat selection. However, some important issues, such as the worldwide emergence of highly transmissible P. aeruginosa clones among cystic fibrosis (CF) patients and the spread and persistence of multidrug resistant (MDR) strains in hospital wards with high antibiotic pressure, remain contentious. To further investigate the population structure of P. aeruginosa, eight parameters were analyzed and combined for 328 unrelated isolates, collected over the last 125 years from 69 localities in 30 countries on five continents, from diverse clinical (human and animal) and environmental habitats. The analysed parameters were: i) O serotype, ii) Fluorescent Amplified-Fragment Length Polymorphism (FALFP) pattern, nucleotide sequences of outer membrane protein genes, iii) oprI, iv) oprL, v) oprD, vi) pyoverdine receptor gene profile (fpvA type and fpvB prevalence), and prevalence of vii) exoenzyme genes exoS and exoU and viii) group I pilin glycosyltransferase gene tfpO. These traits were combined and analysed using biological data analysis software and visualized in the form of a minimum spanning tree (MST). We revealed a network of relationships between all analyzed parameters and non-congruence between experiments. At the same time we observed several conserved clones, characterized by an almost identical data set. These observations confirm the nonclonal epidemic population structure of P. aeruginosa, a superficially clonal structure with frequent recombinations, in which occasionally highly successful epidemic clones arise. One of these clones is the renown and widespread MDR serotype O12 clone. On the other hand, we found no evidence for a widespread CF transmissible clone. All but one of the 43 analysed CF strains belonged to a ubiquitous P

  18. A novel enterocin T1 with anti-Pseudomonas activity produced by Enterococcus faecium T1 from Chinese Tibet cheese.

    PubMed

    Liu, Hui; Zhang, Lanwei; Yi, Huaxi; Han, Xue; Gao, Wei; Chi, Chunliang; Song, Wei; Li, Haiying; Liu, Chunguang

    2016-02-01

    An enterocin-producing Enterococcus faecium T1 was isolated from Chinese Tibet cheese. The enterocin was purified by SP-Sepharose and reversed phase HPLC. It was identified as unique from other reported bacteriocins based on molecular weight (4629 Da) and amino acid compositions; therefore it was subsequently named enterocin T1. Enterocin T1 was stable at 80-100 °C and over a wide pH range, pH 3.0-10.0. Protease sensitivity was observed to trypsin, pepsin, papain, proteinase K, and pronase E. Importantly, enterocin T1 was observed to inhibit the growth of numerous Gram-negative and Gram-positive bacteria including Pseudomonas putida, Pseudomonas aeruginosa, Pseudomonas fluorescens, Escherichia coli, Salmonella typhimurium, Shigella flexneri, Shigella sonnei, Staphylococcus aureus, Listeria monocytogenes. Take together, these results suggest that enterocin T1 is a novel bacteriocin with the potential to be used as a bio-preservative to control Pseudomonas spp. in food.

  19. Staphylococcus aureus Protein A Mediates Interspecies Interactions at the Cell Surface of Pseudomonas aeruginosa

    PubMed Central

    Armbruster, Catherine R.; Wolter, Daniel J.; Mishra, Meenu; Hayden, Hillary S.; Radey, Matthew C.; Merrihew, Gennifer; MacCoss, Michael J.; Burns, Jane; Wozniak, Daniel J.

    2016-01-01

    ABSTRACT While considerable research has focused on the properties of individual bacteria, relatively little is known about how microbial interspecies interactions alter bacterial behaviors and pathogenesis. Staphylococcus aureus frequently coinfects with other pathogens in a range of different infectious diseases. For example, coinfection by S. aureus with Pseudomonas aeruginosa occurs commonly in people with cystic fibrosis and is associated with higher lung disease morbidity and mortality. S. aureus secretes numerous exoproducts that are known to interact with host tissues, influencing inflammatory responses. The abundantly secreted S. aureus staphylococcal protein A (SpA) binds a range of human glycoproteins, immunoglobulins, and other molecules, with diverse effects on the host, including inhibition of phagocytosis of S. aureus cells. However, the potential effects of SpA and other S. aureus exoproducts on coinfecting bacteria have not been explored. Here, we show that S. aureus-secreted products, including SpA, significantly alter two behaviors associated with persistent infection. We found that SpA inhibited biofilm formation by specific P. aeruginosa clinical isolates, and it also inhibited phagocytosis by neutrophils of all isolates tested. Our results indicate that these effects were mediated by binding to at least two P. aeruginosa cell surface structures—type IV pili and the exopolysaccharide Psl—that confer attachment to surfaces and to other bacterial cells. Thus, we found that the role of a well-studied S. aureus exoproduct, SpA, extends well beyond interactions with the host immune system. Secreted SpA alters multiple persistence-associated behaviors of another common microbial community member, likely influencing cocolonization and coinfection with other microbes. PMID:27222468

  20. Chemotaxis of Pseudomonas putida toward chlorinated benzoates

    SciTech Connect

    Harwood, C.S.; Parales, R.E.; Dispensa, M. )

    1990-05-01

    The chlorinated aromatic acids 3-chlorobenzoate and 4-chlorobenzoate are chemoattractants for Pseudomonas putida PRS2000. These compounds are detected by a chromosomally encoded chemotactic response to benzoate which is inducible by {beta}-ketoadipate, and intermediate of benzoate catabolism. Plasmid pAC27, encoding enzymes for 3-chlorobenzoate degradation, does not appear to carry genes for chemotaxis toward chlorinated compounds.

  1. New Pseudomonas spp. Are Pathogenic to Citrus

    PubMed Central

    Beiki, Farid; Busquets, Antonio; Gomila, Margarita; Rahimian, Heshmat; Lalucat, Jorge; García-Valdés, Elena

    2016-01-01

    Five putative novel Pseudomonas species shown to be pathogenic to citrus have been characterized in a screening of 126 Pseudomonas strains isolated from diseased citrus leaves and stems in northern Iran. The 126 strains were studied using a polyphasic approach that included phenotypic characterizations and phylogenetic multilocus sequence analysis. The pathogenicity of these strains against 3 cultivars of citrus is demonstrated in greenhouse and field studies. The strains were initially grouped phenotypically and by their partial rpoD gene sequences into 11 coherent groups in the Pseudomonas fluorescens phylogenetic lineage. Fifty-three strains that are representatives of the 11 groups were selected and analyzed by partial sequencing of their 16S rRNA and gyrB genes. The individual and concatenated partial sequences of the three genes were used to construct the corresponding phylogenetic trees. The majority of the strains were identified at the species level: P. lurida (5 strains), P. monteilii (2 strains), P. moraviensis (1 strain), P. orientalis (16 strains), P. simiae (7 strains), P. syringae (46 strains, distributed phylogenetically in at least 5 pathovars), and P. viridiflava (2 strains). This is the first report of pathogenicity on citrus of P. orientalis, P. simiae, P. lurida, P. moraviensis and P. monteilii strains. The remaining 47 strains that could not be identified at the species level are considered representatives of at least 5 putative novel Pseudomonas species that are not yet described. PMID:26919540

  2. Biodegradation of chlorpyrifos by bacterial genus Pseudomonas.

    PubMed

    Gilani, Razia Alam; Rafique, Mazhar; Rehman, Abdul; Munis, Muhammad Farooq Hussain; Rehman, Shafiq Ur; Chaudhary, Hassan Javed

    2016-02-01

    Chlorpyrifos is an organophosphorus pesticide commonly used in agriculture. It is noxious to a variety of organisms that include living soil biota along with beneficial arthropods, fish, birds, humans, animals, and plants. Exposure to chlorpyrifos may cause detrimental effects as delayed seedling emergence, fruit deformities, and abnormal cell division. Contamination of chlorpyrifos has been found about 24 km from the site of its application. There are many physico-chemical and biological approaches to remove organophosphorus pesticides from the ecosystem, among them most promising is biodegradation. The 3,5,6-trichloro-2-pyridinol (TCP) and diethylthiophosphate (DETP) as primary products are made when chlorpyrifos is degraded by soil microorganisms which further break into nontoxic metabolites as CO(2), H(2)O, and NH(3). Pseudomonas is a diversified genus possessing a series of catabolic pathways and enzymes involved in pesticide degradation. Pseudomonas putida MAS-1 is reported to be more efficient in chlorpyrifos degradation by a rate of 90% in 24 h among Pseudomonas genus. The current review analyzed the comparative potential of bacterial species in Pseudomonas genus for degradation of chlorpyrifos thus, expressing an ecofriendly approach for the treatment of environmental contaminants like pesticides.

  3. New Pseudomonas spp. Are Pathogenic to Citrus.

    PubMed

    Beiki, Farid; Busquets, Antonio; Gomila, Margarita; Rahimian, Heshmat; Lalucat, Jorge; García-Valdés, Elena

    2016-01-01

    Five putative novel Pseudomonas species shown to be pathogenic to citrus have been characterized in a screening of 126 Pseudomonas strains isolated from diseased citrus leaves and stems in northern Iran. The 126 strains were studied using a polyphasic approach that included phenotypic characterizations and phylogenetic multilocus sequence analysis. The pathogenicity of these strains against 3 cultivars of citrus is demonstrated in greenhouse and field studies. The strains were initially grouped phenotypically and by their partial rpoD gene sequences into 11 coherent groups in the Pseudomonas fluorescens phylogenetic lineage. Fifty-three strains that are representatives of the 11 groups were selected and analyzed by partial sequencing of their 16S rRNA and gyrB genes. The individual and concatenated partial sequences of the three genes were used to construct the corresponding phylogenetic trees. The majority of the strains were identified at the species level: P. lurida (5 strains), P. monteilii (2 strains), P. moraviensis (1 strain), P. orientalis (16 strains), P. simiae (7 strains), P. syringae (46 strains, distributed phylogenetically in at least 5 pathovars), and P. viridiflava (2 strains). This is the first report of pathogenicity on citrus of P. orientalis, P. simiae, P. lurida, P. moraviensis and P. monteilii strains. The remaining 47 strains that could not be identified at the species level are considered representatives of at least 5 putative novel Pseudomonas species that are not yet described.

  4. High pressure inactivation of Pseudomonas in black truffle - comparison with Pseudomonas fluorescens in tryptone soya broth

    NASA Astrophysics Data System (ADS)

    Ballestra, Patricia; Verret, Catherine; Cruz, Christian; Largeteau, Alain; Demazeau, Gerard; El Moueffak, Abdelhamid

    2010-03-01

    Pseudomonas is one of the most common genera in black Perigord truffle. Its inactivation by high pressure (100-500 MPa/10 min) applied on truffles at sub-zero or low temperatures was studied and compared with those of Pseudomonas fluorescens in tryptone soya broth. Pressurization of truffles at 300 MPa/4 °C reduced the bacterial count of Pseudomonas by 5.3 log cycles. Higher pressures of 400 or 500 MPa, at 4 °C or 20 °C, allowed us to slightly increase the level of destruction to the value of ca. 6.5 log cycles but did not permit us to completely inactivate Pseudomonas. The results showed a residual charge of about 10 CFU/g. Pressure-shift freezing of truffles, which consists in applying a pressure of 200 MPa/-18 °C for 10 min and then quickly releasing this pressure to induce freezing, reduced the population of Pseudomonas by 3.3 log cycles. The level of inactivation was higher than those obtained with conventional freezing. Endogenous Pseudomonas in truffle was shown to be more resistant to high pressure treatments than P. fluorescens used for inoculation of broths.

  5. IS1491 from Pseudomonas alcaligenes NCIB 9867: characterization and distribution among Pseudomonas species.

    PubMed

    Yeo, C C; Wong, D T; Poh, C L

    1998-01-01

    A new insertion sequence, IS1491, has been cloned and sequenced. The 2489-bp IS1491 was isolated from a Pseudomonas alcaligenes NCIB 9867 (strain P25X) 4.8-kb PstI chromosomal fragment. IS1491 is flanked by an imperfect inverted repeat of 23 bp and carries two overlapping open reading frames, ORF1 and ORF2. Both ORF1 and ORF2 displayed homology to the IstA-like and IstB-like transposases encoded by the IS21 family of insertion sequences, which include two IS elements previously isolated from P. alcaligenes P25X, IS1474, and IS1475 (Yeo, C. C., and Poh, C. L. (1997). FEMS Microbiol. Lett. 149, 257-263). Transposition assays showed that IS1491 transposed at a frequency of approximately 1.4 x 10(-6). Transposition of IS1491 into the target pRK415 replicon was observed but when ORF2 was disrupted, a fusion between the donor and target replicons was detected. IS1491-like sequences were detected in total DNA of Pseudomonas putida NCIB 9869 (strain P35X), Pseudomonas aeruginosa, Pseudomonas stutzeri, Pseudomonas syringae, Pseudomonas mendocina, Comomonas acidovorans, and Comomonas testosteroni by hybridization with IS1491 DNA.

  6. Antimicrobial activities of rhizobacterial strains of Pseudomonas and Bacillus strains isolated from rhizosphere soil of carnation (Dianthus caryophyllus cv. Sunrise).

    PubMed

    Sharma, Sapna; Kaur, Mohinder

    2010-06-01

    Under the present study, an attempt was made to characterize rhizobacteria i.e. Pseudomonas and Bacillus species isolated from rhizosphere of carnation to evaluate their growth promoting effect on carnation so as to select and develop more efficient indigenous plant growth promoting and disease suppressing bioagents of specific soil type and specific plant type. Maximum strains of Pseudomonas and Bacillus sp. showed significant antimicrobial activities against most of the microorganisms tested. On the basis of in vitro antagonistic activities, the best strains were selected and used in field trial to study the influence of these strains on the growth of carnation. Results have shown marked effect on growth parameters and disease incidence has also been reduced significantly.

  7. Biological control of Sclerotinia sclerotiorum (Lib.) de Bary, the causal agent of white mold, by Pseudomonas species on canola petals.

    PubMed

    Behnam, S; Ahmadzadeh, M; Sharifi Tehrani, A; Hedjaroude, Gh A; Farzaneh, M

    2007-01-01

    Sclerotinia sclerotiorum is an important pathogen on canola. Due to the public concern over pesticide use, alternative methods of disease control, such as biological control, should be considered. Several bacterial strains were isolated from canola and soja plants. Inhibition of S. sclerotiorum by bacterial strains in vitro was assayed on PDA medium in dual culture test. Eight Pseudomonas sp. strains (PB-3, PB-4, PB-5, PB-6, PB-7, PB-8, PB-10 and PB-11) caused inhibition zone against 5. sclerotiorum hyphal growth. The biocontrol potential of the bacteria was tested in a plant assay. Disease suppression was investigated using a petal inoculation technique. Canola petals were pretreated with bacteria, and then inoculated with 5. sclerotiorum ascospores 24 h later. Greenhouse experiment showed that application of Pseudomonas sp. strains (1 x 10(8) cfu ml(-1)) effectively suppressed S. sclerotiorum (1 x 10(5) ascospores ml(-1)) on petals and all of them achieved significant (P<0.01) disease suppression. Fourteen days after inoculation, strain PB-3 had 88/7% disease control and strain PB-4 had 69/9% disease control. Result from all studies indicates PB-3 to be effective biocontrol against S. sclerotiorum of canola. PB-3, PB-4, PB-7, PB-8, PB-10 and PB-11 were identified as Pseudomonas fluorescens biovar III. PB-5 and PB-6 was identified as Pseudomonas fluorescens biovar II. Strains PB-3, PB-4, PB-6, PB-10 and PB-11 produced protease and HCN. Strain PB-5 produce protease; no HCN.

  8. Enhanced annotations and features for comparing thousands of Pseudomonas genomes in the Pseudomonas genome database.

    PubMed

    Winsor, Geoffrey L; Griffiths, Emma J; Lo, Raymond; Dhillon, Bhavjinder K; Shay, Julie A; Brinkman, Fiona S L

    2016-01-04

    The Pseudomonas Genome Database (http://www.pseudomonas.com) is well known for the application of community-based annotation approaches for producing a high-quality Pseudomonas aeruginosa PAO1 genome annotation, and facilitating whole-genome comparative analyses with other Pseudomonas strains. To aid analysis of potentially thousands of complete and draft genome assemblies, this database and analysis platform was upgraded to integrate curated genome annotations and isolate metadata with enhanced tools for larger scale comparative analysis and visualization. Manually curated gene annotations are supplemented with improved computational analyses that help identify putative drug targets and vaccine candidates or assist with evolutionary studies by identifying orthologs, pathogen-associated genes and genomic islands. The database schema has been updated to integrate isolate metadata that will facilitate more powerful analysis of genomes across datasets in the future. We continue to place an emphasis on providing high-quality updates to gene annotations through regular review of the scientific literature and using community-based approaches including a major new Pseudomonas community initiative for the assignment of high-quality gene ontology terms to genes. As we further expand from thousands of genomes, we plan to provide enhancements that will aid data visualization and analysis arising from whole-genome comparative studies including more pan-genome and population-based approaches.

  9. Identification of non-pseudomonad bacteria from fruit bodies of wild agaricales fungi that detoxify tolaasin produced by Pseudomonas tolaasii.

    PubMed

    Tsukamoto, Takanori; Murata, Hitoshi; Shirata, Akira

    2002-10-01

    Bacterial isolates from wild Agaricales fungi detoxified tolaasin, the inducer of brown blotch disease of cultivated mushrooms produced by Pseudomonas tolaasii. Mycetocola tolaasinivorans and Mycetocola lacteus were associated with fruit bodies of wild Pleurotus ostreatus and wild Lepista nuda, respectively. Tolaasin-detoxifying bacteria belonging to other genera were found in various wild mushrooms. An Acinetobacter sp. was isolated from fruit bodies of Tricholoma matsutake, Bacillus pumilus was isolated from Coprinus disseminatus, and Sphingobacterium multivorum was isolated from Clitocybe clavipes. A Pedobacter sp., which seemed not be identifiable as any known bacterial species, was isolated from a Clitocybe sp. Tolaasin-detoxifying bacteria identified thus far were attached to the surface of mycelia rather than residing within the fungal cells. M. tolaasinivorans, M. lacteus, B. pumilus, the Pedobacter sp., and S. multivorum efficiently detoxified tolaasin and strongly suppressed brown blotch development in cultivated P. ostreatus and Agaricus bisporus in vitro, but the Acinetobacter sp. did so less efficiently. These bacteria may be useful for the elucidation of mechanisms involved in tolaasin-detoxification, and may become biological control agents of mushroom disease.

  10. Adhesion of Pseudomonas fluorescens onto nanophase materials

    NASA Astrophysics Data System (ADS)

    Webster, Thomas J.; Tong, Zonghua; Liu, Jin; Banks, M. Katherine

    2005-07-01

    Nanobiotechnology is a growing area of research, primarily due to the potentially numerous applications of new synthetic nanomaterials in engineering/science. Although various definitions have been given for the word 'nanomaterials' by many different experts, the commonly accepted one refers to nanomaterials as those materials which possess grains, particles, fibres, or other constituent components that have one dimension specifically less than 100 nm. In biological applications, most of the research to date has focused on the interactions between mammalian cells and synthetic nanophase surfaces for the creation of better tissue engineering materials. Although mammalian cells have shown a definite positive response to nanophase materials, information on bacterial interactions with nanophase materials remains elusive. For this reason, this study was designed to assess the adhesion of Pseudomonas fluorescens on nanophase compared to conventional grain size alumina substrates. Results provide the first evidence of increased adhesion of Pseudomonas fluorescens on alumina with nanometre compared to conventional grain sizes. To understand more about the process, polymer (specifically, poly-lactic-co-glycolic acid or PLGA) casts were made of the conventional and nanostructured alumina surfaces. Results showed similar increased Pseudomonas fluorescens capture on PLGA casts of nanostructured compared to conventional alumina as on the alumina itself. For these reasons, a key material property shown to enhance bacterial adhesion was elucidated in this study for both polymers and ceramics: nanostructured surface features.

  11. Pseudomonas biofilm matrix composition and niche biology

    PubMed Central

    Mann, Ethan E.; Wozniak, Daniel J.

    2014-01-01

    Biofilms are a predominant form of growth for bacteria in the environment and in the clinic. Critical for biofilm development are adherence, proliferation, and dispersion phases. Each of these stages includes reinforcement by, or modulation of, the extracellular matrix. Pseudomonas aeruginosa has been a model organism for the study of biofilm formation. Additionally, other Pseudomonas species utilize biofilm formation during plant colonization and environmental persistence. Pseudomonads produce several biofilm matrix molecules, including polysaccharides, nucleic acids, and proteins. Accessory matrix components shown to aid biofilm formation and adaptability under varying conditions are also produced by pseudomonads. Adaptation facilitated by biofilm formation allows for selection of genetic variants with unique and distinguishable colony morphology. Examples include rugose small-colony variants and wrinkly spreaders (WS), which over produce Psl/Pel or cellulose, respectively, and mucoid bacteria that over produce alginate. The well-documented emergence of these variants suggests that pseudomonads take advantage of matrix-building subpopulations conferring specific benefits for the entire population. This review will focus on various polysaccharides as well as additional Pseudomonas biofilm matrix components. Discussions will center on structure–function relationships, regulation, and the role of individual matrix molecules in niche biology. PMID:22212072

  12. Pseudomonas aeruginosa protease IV degrades surfactant proteins and inhibits surfactant host defense and biophysical functions.

    PubMed

    Malloy, Jaret L; Veldhuizen, Ruud A W; Thibodeaux, Brett A; O'Callaghan, Richard J; Wright, Jo Rae

    2005-02-01

    Pulmonary surfactant has two distinct functions within the lung: reduction of surface tension at the air-liquid interface and participation in innate host defense. Both functions are dependent on surfactant-associated proteins. Pseudomonas aeruginosa is primarily responsible for respiratory dysfunction and death in cystic fibrosis patients and is also a leading pathogen in nosocomial pneumonia. P. aeruginosa secretes a number of proteases that contribute to its virulence. We hypothesized that P. aeruginosa protease IV degrades surfactant proteins and results in a reduction in pulmonary surfactant host defense and biophysical functions. Protease IV was isolated from cultured supernatant of P. aeruginosa by gel chromatography. Incubation of cell-free bronchoalveolar lavage fluid with protease IV resulted in degradation of surfactant proteins (SP)-A, -D, and -B. SPs were degraded in a time- and dose-dependent fashion by protease IV, and degradation was inhibited by the trypsin-like serine protease inhibitor Nalpha-p-tosyl-L-lysine-chloromethyl ketone (TLCK). Degradation by protease IV inhibited SP-A- and SP-D-mediated bacterial aggregation and uptake by macrophages. Surfactant treated with protease IV was unable to reduce surface tension as effectively as untreated surfactant, and this effect was inhibited by TLCK. We speculate that protease IV may be an important contributing factor to the development and propagation of acute lung injury associated with P. aeruginosa via loss of surfactant function within the lung.

  13. SP-100 program developments

    NASA Technical Reports Server (NTRS)

    Schnyer, A. D.; Sholtis, J. A., Jr.; Wahlquist, E. J.; Verga, R. L.; Wiley, R. L.

    1985-01-01

    An update is provided on the status of the Sp-100 Space Reactor Power Program. The historical background that led to the program is reviewed and the overall program objectives and development approach are discussed. The results of the mission studies identify applications for which space nuclear power is desirable and even essential. Results of a series of technology feasibility experiments are expected to significantly improve the earlier technology data base for engineering development. The conclusion is reached that a nuclear reactor space power system can be developed by the early 1990s to meet emerging mission performance requirements.

  14. INTRODUCTION OF ATRAZINE-DEGRADING PSEUDOMONAS SP. STRAIN ADP TO ENHANCE PHYTOREMEDIATION OF ATRAZINE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Atrazine (ATR) has been widely applied in the US and Mid Western states. Recently, public health and ecological concerns have been raised about contamination of surface and ground water by ATR and its chlorinated metabolites, due to their toxicity and potential carcinogenic or endocrinology effects....

  15. Introduction of Atrazine-Degrading Pseudomonas SP. Strain ADP to Enhance Phytoremediation of Atrazine

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Atrazine (ATR) has been widely applied in the US Midwestern states. Public health and ecological concerns have been raised about contamination of surface and ground water by ATR and its chlorinated metabolites, due to their toxicity and potential carcinogenic or endocrinology effects. Phytoremediati...

  16. Pseudomonas sp. as a Source of Medium Chain Length Polyhydroxyalkanoates for Controlled Drug Delivery: Perspective

    PubMed Central

    Kabilan, Sujatha; Ayyasamy, Mahalakshmi; Jayavel, Sridhar; Paramasamy, Gunasekaran

    2012-01-01

    Controlled drug delivery technology represents one of the most rapidly advancing areas of science. They offer numerous advantages compared to conventional dosage forms including improved efficacy, reduced toxicity, improved patient compliance and convenience. Over the past several decades, many delivery tools or methods were developed such as viral vector, liposome-based delivery system, polymer-based delivery system, and intelligent delivery system. Recently, nonviral vectors, especially those based on biodegradable polymers, have been widely investigated as vectors. Unlike the other polymers tested, polyhydroxyalkanoates (PHAs) have been intensively investigated as a family of biodegradable and biocompatible materials for in vivo applications as implantable tissue engineering material as well as release vectors for various drugs. On the other hand, the direct use of these polyesters has been hampered by their hydrophobic character and some physical shortcomings, while its random copolymers fulfilled the expectation of biomedical researchers by exhibiting significant mechanical and thermal properties. This paper reviews the strategies adapted to make functional polymer to be utilized as delivery system. PMID:22518140

  17. Pseudomonas kuykendallii sp. nov.: A novel y-Proteobacteria isolated from a hexazinone degrading bioreactor

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Three strains of Gram-negative bacteria designated strains H2T, H6, and H7 were isolated from bioreactors that degraded the herbicide hexazinone. Similar morphological characteristics, cellular fatty acid profiles and 16S rRNA gene sequences show that the isolates are members of the same species. ...

  18. Introduction of Atrazine-Degrading Pseudomonas sp. Strain ADP to Enhance Rhizodegradation of Atrazine

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The herbicide atrazine (ATR) has been widely applied to fields in the U.S. and Midwestern states, resulting in contamination of surface and ground waters. Public health and ecological concerns have been raised due to the toxicity and potential carcinogenic or endocrine disrupting effects of ATR and ...

  19. SP mountain data analysis

    NASA Technical Reports Server (NTRS)

    Rawson, R. F.; Hamilton, R. E.; Liskow, C. L.; Dias, A. R.; Jackson, P. L.

    1981-01-01

    An analysis of synthetic aperture radar data of SP Mountain was undertaken to demonstrate the use of digital image processing techniques to aid in geologic interpretation of SAR data. These data were collected with the ERIM X- and L-band airborne SAR using like- and cross-polarizations. The resulting signal films were used to produce computer compatible tapes, from which four-channel imagery was generated. Slant range-to-ground range and range-azimuth-scale corrections were made in order to facilitate image registration; intensity corrections were also made. Manual interpretation of the imagery showed that L-band represented the geology of the area better than X-band. Several differences between the various images were also noted. Further digital analysis of the corrected data was done for enhancement purposes. This analysis included application of an MSS differencing routine and development of a routine for removal of relief displacement. It was found that accurate registration of the SAR channels is critical to the effectiveness of the differencing routine. Use of the relief displacement algorithm on the SP Mountain data demonstrated the feasibility of the technique.

  20. Why Does the Healthy Cornea Resist Pseudomonas aeruginosa Infection?

    PubMed Central

    Evans, David J.; Fleiszig, Suzanne M. J.

    2013-01-01

    Purpose To provide our perspective on why the cornea is resistant to infection based on our research results with Pseudomonas aeruginosa. Perspective We focus on our current understanding of the interplay between bacteria, tear fluid and the corneal epithelium that determine health as the usual outcome, and propose a theoretical model for how contact lens wear might change those interactions to enable susceptibility to P. aeruginosa infection. Methods Use of “null-infection” in vivo models, cultured human corneal epithelial cells, contact lens-wearing animal models, and bacterial genetics help to elucidate mechanisms by which P. aeruginosa survive at the ocular surface, adheres, and traverses multilayered corneal epithelia. These models also help elucidate the molecular mechanisms of corneal epithelial innate defense. Results and Discussion Tear fluid and the corneal epithelium combine to make a formidable defense against P. aeruginosa infection of the cornea. Part of that defense involves the expression of antimicrobials such as β-defensins, the cathelicidin LL-37, cytokeratin-derived antimicrobial peptides, and RNase7. Immunomodulators such as SP-D and ST2 also contribute. Innate defenses of the cornea depend in part on MyD88, a key adaptor protein of TLR and IL-1R signaling, but the basal lamina represents the final barrier to bacterial penetration. Overcoming these defenses involves P. aeruginosa adaptation, expression of the type three secretion system, proteases, and P. aeruginosa biofilm formation on contact lenses. Conclusion After more than two decades of research focused on understanding how contact lens wear predisposes to P. aeruginosa infection, our working hypothesis places blame for microbial keratitis on bacterial adaptation to ocular surface defenses, combined with changes to the biochemistry of the corneal surface caused by trapping bacteria and tear fluid against the cornea under the lens. PMID:23601656

  1. Simultaneous biodegradation of chlorobenzene and toluene by a Pseudomonas strain

    SciTech Connect

    Pettigrew, C.A.; Haigler, B.E.; Spain, J.C. )

    1991-01-01

    Pseudomonas sp. strain JS6 grows on a wide range of chloro- and methylaromatic substrates. The simultaneous degradation of these compounds is prevented in most previously studied isolates because the catabolic pathways are incompatible. The purpose of this study was to determine whether strain JS6 could degrade mixtures of chloro- and methyl-substituted aromatic compounds. Strain JS6 was maintained in a chemostat on a minimal medium with toluene or chlorobenzene as the sole carbon source, supplied via a syringe pump. Strain JS6 contained an active catechol 2,3-dioxygenase when grown in the presence of chloroaromatic compounds; however, in cell extracts, this enzyme was strongly inhibited by 3-chlorocatechol. When cells grown to steady state on toluene were exposed to 50% toluene-50% chlorobenzene, 3-chlorocatechol and 3-methylcatechol accumulated in the medium and the cell density decreased. After 3 h, the enzyme activities of the modified ortho ring fission pathway were induced, the metabolites disappeared, and the cell density returned to previous levels. In cell extracts, 3-methylcatechol was degraded by both catechol 1,2- and catechol 2,3-dioxygenase. Strain JS62, a catechol 2,3-dioxygenase mutant of JS6, grew on toluene, and ring cleavage of 3-methylcatechol was catalyzed by catechol 1,2-dioxygenase. The transient metabolite 2-methyllactone was identified in chlorobenzene-grown JS6 cultures exposed to toluene. These results indicate that strain JS6 can degrade mixtures of chloro- and methylaromatic compounds by means of a modified ortho ring fission pathway.

  2. The New Antimicrobial Peptide SpHyastatin from the Mud Crab Scylla paramamosain with Multiple Antimicrobial Mechanisms and High Effect on Bacterial Infection

    PubMed Central

    Shan, Zhongguo; Zhu, Kexin; Peng, Hui; Chen, Bei; Liu, Jie; Chen, Fangyi; Ma, Xiaowan; Wang, Shuping; Qiao, Kun; Wang, Kejian

    2016-01-01

    SpHyastatin was first identified as a new cationic antimicrobial peptide in hemocytes of the mud crab Scylla paramamosain. Based on the amino acid sequences deduced, it was predicted that this peptide was composed of two different functional domains, a proline-rich domain (PRD) and a cysteine-rich domain (CRD). The recombinant product of SpHyastatin displayed potent antimicrobial activities against the human pathogen Staphylococcus aureus and the aquatic animal pathogens Aeromonas hydrophila and Pseudomonas fluorescens. Compared with the CRD of SpHyastatin, the PRD presented better antimicrobial and chitin binding activities, but both regions were essential for allowing SpHyastatin complete antimicrobial activity. The binding properties of SpHyastatin to different microbial surface molecules suggested that this might be an initial and crucial step for performing its antimicrobial activities. Evaluated using propidium iodide uptake assays and scanning electron microscopy images, the antimicrobial mechanism of SpHyastatin was found to be prone to disrupt cell membrane integrity. Interestingly, SpHyastatin exerted its role specifically on the surface of S. aureus and Pichia pastoris whereas it directly killed P. fluorescens through simultaneous targeting the membrane and the cytoplasm, indicating that SpHyastatin could use different antimicrobial mechanisms to kill different species of microbes. As expected, the recombinant SpHyastatin increased the survival rate of crabs challenged with Vibrio parahaemolyticus. In addition, SpHyastatin could modulate some V. parahaemolyticus-responsive genes in S. paramamosain. PMID:27493644

  3. High quality draft genome sequences of Pseudomonas fulva DSM 17717(T), Pseudomonas parafulva DSM 17004(T) and Pseudomonas cremoricolorata DSM 17059(T) type strains.

    PubMed

    Peña, Arantxa; Busquets, Antonio; Gomila, Margarita; Mulet, Magdalena; Gomila, Rosa M; Reddy, T B K; Huntemann, Marcel; Pati, Amrita; Ivanova, Natalia; Markowitz, Victor; García-Valdés, Elena; Göker, Markus; Woyke, Tanja; Klenk, Hans-Peter; Kyrpides, Nikos; Lalucat, Jorge

    2016-01-01

    Pseudomonas has the highest number of species out of any genus of Gram-negative bacteria and is phylogenetically divided into several groups. The Pseudomonas putida phylogenetic branch includes at least 13 species of environmental and industrial interest, plant-associated bacteria, insect pathogens, and even some members that have been found in clinical specimens. In the context of the Genomic Encyclopedia of Bacteria and Archaea project, we present the permanent, high-quality draft genomes of the type strains of 3 taxonomically and ecologically closely related species in the Pseudomonas putida phylogenetic branch: Pseudomonas fulva DSM 17717(T), Pseudomonas parafulva DSM 17004(T) and Pseudomonas cremoricolorata DSM 17059(T). All three genomes are comparable in size (4.6-4.9 Mb), with 4,119-4,459 protein-coding genes. Average nucleotide identity based on BLAST comparisons and digital genome-to-genome distance calculations are in good agreement with experimental DNA-DNA hybridization results. The genome sequences presented here will be very helpful in elucidating the taxonomy, phylogeny and evolution of the Pseudomonas putida species complex.

  4. Diversity of endophytic Pseudomonas in Halimione portulacoides from metal(loid)-polluted salt marshes.

    PubMed

    Rocha, Jaqueline; Tacão, Marta; Fidalgo, Cátia; Alves, Artur; Henriques, Isabel

    2016-07-01

    Phytoremediation assisted by bacteria is seen as a promising alternative to reduce metal contamination in the environment. The main goal of this study was to characterize endophytic Pseudomonas isolated from Halimione portulacoides, a metal-accumulator plant, in salt marshes contaminated with metal(loid)s. Phylogenetic analysis based on 16S rRNA and gyrB genes showed that isolates affiliated with P. sabulinigri (n = 16), P. koreensis (n = 10), P. simiae (n = 5), P. seleniipraecipitans (n = 2), P. guineae (n = 2), P. migulae (n = 1), P. fragi (n = 1), P. xanthomarina (n = 1), and Pseudomonas sp. (n = 1). Most of these species have never been described as endophytic. The majority of the isolates were resistant to three or more metal(loid)s. Antibiotic resistance was frequent among the isolates but most likely related to species-intrinsic features. Common acquired antibiotic resistance genes and integrons were not detected. Plasmids were detected in 43.6 % of the isolates. Isolates that affiliated with different species shared the same plasmid profile but attempts to transfer metal resistance to receptor strains were not successful. Phosphate solubilization and IAA production were the most prevalent plant growth promoting traits, and 20 % of the isolates showed activity against phytopathogenic bacteria. Most isolates produced four or more extracellular enzymes. Preliminary results showed that two selected isolates promote Arabidopsis thaliana root elongation. Results highlight the diversity of endophytic Pseudomonas in H. portulacoides from contaminated sites and their potential to assist phytoremediation by acting as plant growth promoters and as environmental detoxifiers.

  5. Expression, purification, crystallization and preliminary X-ray analysis of Pseudomonas aeruginosa AlgL

    PubMed Central

    Wolfram, Francis; Arora, Kritica; Robinson, Howard; Neculai, Ana Mirela; Yip, Patrick; Howell, P. Lynne

    2012-01-01

    The periplasmic alginate lyase AlgL is essential for the synthesis and export of the exopolysaccharide alginate in Pseudomonas sp. and also plays a role in its depolymerization. P. aeruginosa PAO1 AlgL has been overexpressed and purified and diffraction-quality crystals were grown using the hanging-drop vapour-diffusion method. The crystals grew as thin plates, with unit-cell parameters a = 56.4, b = 59.6, c = 102.1 Å, α = β = γ = 90°. The AlgL crystals exhibited the symmetry of space group P212121 and diffracted to a minimum d-­spacing of 1.64 Å. Based on the Matthews coefficient (V M = 2.20 Å3 Da−1), one molecule is estimated to be present in the asymmetric unit. PMID:22691793

  6. Expression, purification, crystallization and preliminary X-ray analysis of Pseudomonas aeruginosa AlgX

    PubMed Central

    Weadge, Joel T.; Yip, Patrick P.; Robinson, Howard; Arnett, Krista; Tipton, Peter A.; Howell, P. Lynne

    2010-01-01

    AlgX is a periplasmic protein required for the production of the exopoly­saccharide alginate in Pseudomonas sp. and Azotobacter vinelandii. AlgX has been overexpressed and purified and diffraction-quality crystals have been grown using iterative seeding and the hanging-drop vapor-diffusion method. The crystals grew as flat plates with unit-cell parameters a = 46.4, b = 120.6, c = 86.9 Å, β = 95.7°. The crystals exhibited the symmetry of space group P21 and diffracted to a minimum d-spacing of 2.1 Å. On the basis of the Matthews coefficient (V M = 2.25 Å3 Da−1), two molecules were estimated to be present in the asymmetric unit. PMID:20445266

  7. Expression, purification, crystallization and preliminary X-ray analysis of Pseudomonas aeruginosa AlgX

    SciTech Connect

    Weadge, J.T.; Robinson, H.; Yip, P. P.; Arnett, K.; Tipton, P. A.; Howell, P. L.

    2010-05-01

    AlgX is a periplasmic protein required for the production of the exopolysaccharide alginate in Pseudomonas sp. and Azotobacter vinelandii. AlgX has been overexpressed and purified and diffraction-quality crystals have been grown using iterative seeding and the hanging-drop vapor-diffusion method. The crystals grew as flat plates with unit-cell parameters a = 46.4, b = 120.6, c = 86.9 {angstrom}, {beta} = 95.7{sup o}. The crystals exhibited the symmetry of space group P2{sub 1} and diffracted to a minimum d-spacing of 2.1 {angstrom}. On the basis of the Matthews coefficient (V{sub M} = 2.25 {angstrom}{sup 3} Da{sup -1}), two molecules were estimated to be present in the asymmetric unit.

  8. Siderotyping of fluorescent pseudomonads: characterization of pyoverdines of Pseudomonas fluorescens and Pseudomonas putida strains from Antarctica.

    PubMed

    Meyer, J M; Stintzi, A; Coulanges, V; Shivaji, S; Voss, J A; Taraz, K; Budzikiewicz, H

    1998-11-01

    Five independent fluorescent pseudomonad isolates originating from Antarctica were analysed for their pyoverdine systems. A pyoverdine-related siderotyping, which involved pyoverdine-induced growth stimulation, pyoverdine-mediated iron uptake, pyoverdine analysis by electrophoresis and isoelectric focusing, revealed three different pyoverdine-related siderotypes among the five isolates. One siderotype, including Pseudomonas fluorescens 1W and P. fluorescens 10CW, was identical to that of P. fluorescens ATCC 13525. Two other strains, P. fluorescens 9AW and Pseudomonas putida 9BW, showed identical pyoverdine-related behaviour to each other, whereas the fifth strain, P. fluorescens 51W, had unique features compared to the other strains or to a set of 12 fluorescent Pseudomonas strains used as comparison material. Elucidation of the structure of the pyoverdines produced by the Antarctic strains supported the accuracy of the siderotyping methodology by confirming that pyoverdines from strains 1W and 10CW had the same structures as the P. fluorescens ATCC 13525 pyoverdine, whereas the 9AW and 9BW pyoverdines are probably identical with the pyoverdine of P. fluorescens strain 244. Pyoverdine from strain 51W appeared to be a novel pyoverdine since its structure was different from all previously established pyoverdine structures. Together with the conclusion that the Antarctic Pseudomonas strains have no special features at the level of their pyoverdines and pyoverdine-mediated iron metabolism compared to worldwide strains, the present work demonstrates that siderotyping provides a rapid means of screening for novel pyoverdines.

  9. Rhizoxin analogs contribute to the biocontrol activity of a newly isolated pseudomonas strain.

    PubMed

    Takeuchi, Kasumi; Noda, Naomi; Katayose, Yuichi; Mukai, Yoshiyuki; Numa, Hisataka; Yamada, Kosumi; Someya, Nobutaka

    2015-03-01

    Two strains of Pseudomonas sp., Os17 and St29, were newly isolated from the rhizosphere of rice and potato, respectively, by screening for 2,4-diacetylphloroglucinol producers. These strains were found to be the same species and were the closest to but different from Pseudomonas protegens among the sequenced pseudomonads, based on 16S ribosomal RNA gene and whole-genome analyses. Strain Os17 was as effective a biocontrol agent as reported for P. protegens Cab57, whereas strain St29 was less effective. The whole-genome sequences of these strains were obtained: the genomes are organized into a single circular chromosome with 6,885,464 bp, 63.5% G+C content, and 6,195 coding sequences for strain Os17; and with 6,833,117 bp, 63.3% G+C content, and 6,217 coding sequences for strain St29. Comparative genome analysis of these strains revealed that the complete rhizoxin analog biosynthesis gene cluster (approximately 79 kb) found in the Os17 genome was absent from the St29 genome. In an rzxB mutant, which lacks the polyketide synthase essential for the production of rhizoxin analogs, the growth inhibition activity against fungal and oomycete pathogens and the plant protection efficacy were attenuated compared with those of wild-type Os17. These findings suggest that rhizoxin analogs are important biocontrol factors of this strain.

  10. Evaluation and biochemical characterization of a distinctive pyoverdin from a pseudomonas isolated from chickpea rhizosphere.

    PubMed

    Tank, Neelam; Rajendran, Narayanan; Patel, Baldev; Saraf, Meenu

    2012-04-01

    Microbial siderophores confiscate the available ferric ions around the roots and trigger a reaction resulting in plant growth promotion. In our study, a high level of siderophore production was observed from a newly isolated Pseudomonas sp. from the rhizosphere of Chickpea plants. Under an iron depleted condition in Standard Succinic acid medium a 1000 μgmL(-1) of siderophore production was achieved. Increasing the concentration of iron showed an inverse relationship between growth and siderophore production. Fourier Transform Infrared Spectroscopy (FTIR) analysis of the purified crystals, its UV spectral analysis and High Pressure Liquid Chromatography (HPLC) revealed the identity of the siderophore as similar to that of pyoverdin with distinctive characters. Electron spray ionization mass spectroscopy (ESIMS) shows presence of abundance of A1 ions (419 m/z) and branching of amino acids from B1-B5. This pyoverdin contains a cyclic tetra peptide but Serine and Arginine are missing. Based on our analysis and deviations from the reported structure of pyoverdin it is suggested that this pseudomonas produces distinctly characterized pyoverdin siderophore.

  11. Stress response of Pseudomonas species to silver nanoparticles at the molecular level.

    PubMed

    Soni, Deepika; Bafana, Amit; Gandhi, Deepa; Sivanesan, Saravanadevi; Pandey, Ram Avatar

    2014-09-01

    In recent years, silver nanoparticles (AgNPs) have been shown to possess broad antibacterial activity. The present study investigated the cytotoxicity of AgNPs to a common soil bacterium, Pseudomonas sp. The molecular mechanism involved in its stress response to AgNPs was also studied. The minimum inhibitory concentration (MIC) of AgNPs was found to be 0.2 mg/L. At a sublethal concentration of 0.1 mg/L AgNPs, the protein expression profile of Pseudomonas showed overexpression of stress proteins such as ribosomal proteins S2 and L9, alkyl hydroperoxide reductase/thiol-specific antioxidant (AhpC/TSA) family protein, and keto-hydroxyglutarate aldolase (KHGA). The upregulation of these proteins was further confirmed by quantitative polymerase chain reaction. The results showed increased expression of ribosomal protein S2, KHGA, AhpC/TSA, and ribosomal protein L9 by 1.09-, 3.41-, 1.52-, and 1.56-fold, respectively (p < 0.05), after AgNP exposure compared with control. The present study clearly demonstrates that AgNPs are toxic to soil bacteria and induce oxidative and metabolic stress.

  12. Resistance of Pseudomonas to Quaternary Ammonium Compounds. I. Growth in Benzalkonium Chloride Solution

    PubMed Central

    Adair, Frank W.; Geftic, Sam G.; Gelzer, Justus

    1969-01-01

    Resistant cells of Pseudomonas aeruginosa and a waterborne Pseudomonas sp. (strain Z-R) were able to multiply in nitrogen-free minimal salts solution containing various concentrations of commercially prepared, ammonium acetate-buffered benzalkonium chloride (CBC), a potent antimicrobial agent. As the CBC concentration increased, growth increased until a point was reached at which the extent of growth leveled off or was completely depressed. Minimal salts solutions of pure benzalkonium chloride (PBC) containing no ammonium acetate did not support bacterial growth. When ammonium acetate was added to PBC solutions in the same concentrations found in CBC solutions, growth patterns developed that were comparable to those found with CBC. Likewise, (NH4)2SO4 added to PBC solutions supported growth of both organisms. P. aeruginosa was initially resistant to CBC levels of 0.02% and it was adapted to tolerate levels as high as 0.36%. Strain Z-R was naturally resistant to 0.4% CBC. Since ammonium acetate, carried over by the CBC used in drug formulations and disinfectant solutions, has the potential to support the growth of resistant bacteria and thus make possible the risk of serious infection, it is suggested that regulations allowing the presence of ammonium acetate in CBC solution be reconsidered. PMID:4984761

  13. Crystal structure of the terminal oxygenase component of cumene dioxygenase from Pseudomonas fluorescens IP01.

    PubMed

    Dong, Xuesong; Fushinobu, Shinya; Fukuda, Eriko; Terada, Tohru; Nakamura, Shugo; Shimizu, Kentaro; Nojiri, Hideaki; Omori, Toshio; Shoun, Hirofumi; Wakagi, Takayoshi

    2005-04-01

    The crystal structure of the terminal component of the cumene dioxygenase multicomponent enzyme system of Pseudomonas fluorescens IP01 (CumDO) was determined at a resolution of 2.2 A by means of molecular replacement by using the crystal structure of the terminal oxygenase component of naphthalene dioxygenase from Pseudomonas sp. strain NCIB 9816-4 (NphDO). The ligation of the two catalytic centers of CumDO (i.e., the nonheme iron and Rieske [2Fe-2S] centers) and the bridging between them in neighboring catalytic subunits by hydrogen bonds through a single amino acid residue, Asp231, are similar to those of NphDO. An unidentified external ligand, possibly dioxygen, was bound at the active site nonheme iron. The entrance to the active site of CumDO is different from the entrance to the active site of NphDO, as the two loops forming the lid exhibit great deviation. On the basis of the complex structure of NphDO, a biphenyl substrate was modeled in the substrate-binding pocket of CumDO. The residues surrounding the modeled biphenyl molecule include residues that have already been shown to be important for its substrate specificity by a number of engineering studies of biphenyl dioxygenases.

  14. Green rapid biogenic synthesis of bioactive silver nanoparticles (AgNPs) using Pseudomonas aeruginosa.

    PubMed

    Busi, Siddhardha; Rajkumari, Jobina; Ranjan, Bibhuti; Karuganti, Sukumar

    2014-12-01

    The present work was focused on isolating a bacterial strain of Pseudomonas sp. with the ability to synthesise AgNPs rapidly. A strain of Pseudomonas aeruginosa designated JO was found to be a potential candidate for rapid synthesis of AgNPs with a synthesis time of 4h in light, at room temperature which is a shorter time period noticed for the synthesis when compared to the previous reports Biosynthesis of AgNPs was achieved by addition of culture supernatant with aqueous silver nitrate solution (1 mM). The reaction mixture exhibits change in colour from green to brown with a peak at 420 nm corresponding to the plasmon absorbance of AgNPs by UV-vis spectroscopy. The nanoparticles were characterised by X-ray diffraction (XRD), energy-dispersive X-ray analysis, Fourier-transform infrared spectroscopy, scanning electron microscopy (SEM), Zetasizer and transmission electron microscopy (TEM). The XRD spectrum exhibited 2θ values corresponding to the silver nanocrystals. TEM and SEM micrographs revealed the extracellular formation of polydispersed elongated nanoparticles with an average size of 27.5 nm. Synthesised nanoparticles showed antibacterial property against both gram-positive and gram-negative microorganisms, but more effective towards gram-negative.

  15. Degradation kinetics and pathway of phenol by Pseudomonas and Bacillus species.

    PubMed

    Hasan, Syed Adnan; Jabeen, Suraiya

    2015-01-02

    This article elucidates that strain Pseudomonas aeruginosa (IES-Ps-1) is a versatile toxic organic compound degrader. With the degradation of malathion and cypermethrin (studied by other researchers previously), this strain was able to degrade phenol. Two other indigenous soil flora (i.e., Pseudomonas sp. (IES-S) and Bacillus subtilis (IES-B)) were also found to be potential phenol degraders. Phenol was degraded with Monod kinetics during growth in nutrient broth and mineral salts medium. Before entering into the growth inhibition phase, strains IES-Ps-1, IES-S and IES-B could tolerate up to 400, 700 and 500 mg/L phenol, respectively, when contained in nutrient broth. However, according to the Luong-Levenspiel model, the growth of strains IES-Ps-1, IES-S and IES-B would cease at 2000, 2174 and 2190 mg/L phenol, respectively. Strain IES-Ps-1 degraded 700, 900 and 1050 mg/L phenol contained in mineral salts medium with the specific rates of 0.034, 0.075 and 0.021 h(-1), respectively. All these strains grew by making clusters when exposed to phenol in order to prevent damages due to high substrate concentration. These strains transformed phenol into catechol, which was then degraded via ortho-cleavage pathway.

  16. Degradation kinetics and pathway of phenol by Pseudomonas and Bacillus species

    PubMed Central

    Hasan, Syed Adnan; Jabeen, Suraiya

    2015-01-01

    This article elucidates that strain Pseudomonas aeruginosa (IES-Ps-1) is a versatile toxic organic compound degrader. With the degradation of malathion and cypermethrin (studied by other researchers previously), this strain was able to degrade phenol. Two other indigenous soil flora (i.e., Pseudomonas sp. (IES-S) and Bacillus subtilis (IES-B)) were also found to be potential phenol degraders. Phenol was degraded with Monod kinetics during growth in nutrient broth and mineral salts medium. Before entering into the growth inhibition phase, strains IES-Ps-1, IES-S and IES-B could tolerate up to 400, 700 and 500 mg/L phenol, respectively, when contained in nutrient broth. However, according to the Luong–Levenspiel model, the growth of strains IES-Ps-1, IES-S and IES-B would cease at 2000, 2174 and 2190 mg/L phenol, respectively. Strain IES-Ps-1 degraded 700, 900 and 1050 mg/L phenol contained in mineral salts medium with the specific rates of 0.034, 0.075 and 0.021 h−1, respectively. All these strains grew by making clusters when exposed to phenol in order to prevent damages due to high substrate concentration. These strains transformed phenol into catechol, which was then degraded via ortho-cleavage pathway. PMID:26740787

  17. Acetobacter intermedius, sp. nov.

    PubMed

    Boesch, C; Trcek, J; Sievers, M; Teuber, M

    1998-03-01

    Strains of a new species in the genus Acetobacter, for which we propose the name A. intermedius sp. nov., were isolated and characterized in pure culture from different sources (Kombucha beverage, cider vinegar, spirit vinegar) and different countries (Switzerland, Slovenia). The isolated strains grow in media with 3% acetic acid and 3% ethanol as does A. europaeus, do, however, not require acetic acid for growth. These characteristics phenotypically position A. intermedius between A. europaeus and A. xylinus, DNA-DNA hybridizations of A. intermedius-DNA with DNA of the type strains of Acetobacter europaeus, A. xylinus, A. aceti, A. hansenii, A. liquefaciens, A. methanolicus, A. pasteurianus, A. diazotrophicus, Gluconobacter oxydans and Escherichia coli HB 101 indicated less than 60% DNA similarity. The important features of the new species are described. Acetobacter intermedius strain TF2 (DSM11804) isolated from the liquid phase of a tea fungus beverage (Kombucha) is the type strain.

  18. Oxidation of 1-Tetradecene by Pseudomonas aeruginosa

    PubMed Central

    Markovetz, A. J.; Klug, M. J.; Forney, F. W.

    1967-01-01

    Pseudomonas aeruginosa strain Sol 20 was grown on 1-tetradecene as sole carbon source, and a vinyl-unsaturated 14-carbon monocarboxylic acid, 13-tetradecenoic acid, was identified from culture fluid. This acid was not produced when n-tetradecane served as substrate for growth. Oxidation of the methyl group represents one method of attack on the 1-alkene by this organism. Tentative identification of 2-tetradecanol indicates that an attack on the double bond is also occurring. α, ω-Dienes would not support growth. PMID:4962057

  19. A giant Pseudomonas phage from Poland.

    PubMed

    Drulis-Kawa, Zuzanna; Olszak, Tomasz; Danis, Katarzyna; Majkowska-Skrobek, Grazyna; Ackermann, Hans-W

    2014-03-01

    A novel giant phage of the family Myoviridae is described. Pseudomonas phage PA5oct was isolated from a sewage sample from an irrigated field near Wroclaw, Poland. The virion morphology indicates that PA5oct differs from known giant phages. The phage has a head of about 131 nm in diameter and a tail of 136 × 19 nm. Phage PA5oct contains a genome of approximately 375 kbp and differs in size from any tailed phages known. PA5oct was further characterized by determination of its latent period and burst size and its sensitivity to heating, chloroform, and pH.

  20. Binding of germanium of Pseudomonas putida cells

    SciTech Connect

    Klapcinska, B.; Chmielowski, J.

    1986-05-01

    The binding of germanium to Pseudomonas putida ATCC 33015 was investigated by using whole intact cells grown in a medium supplemented with GeO/sub 2/ and catechol or acetate. Electron-microscopic examination of the control and metal-loaded samples revealed that germanium was bound within the cell envelope. A certain number of small electron-dense deposits of the bound element were found in the cytoplasm when the cells were grown in the presence of GeO/sub 2/ and catechol. The study of germanium distribution in cellular fractions revealed that catechol facilitated the intracellular accumulation of this element.

  1. 21 CFR 866.3415 - Pseudomonas spp. serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Pseudomonas spp. serological reagents. 866.3415 Section 866.3415 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES..., abscesses, and meningitis (inflammation of brain membranes). Pseudomonas pseudomallei causes melioidosis,...

  2. 21 CFR 866.3415 - Pseudomonas spp. serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Pseudomonas spp. serological reagents. 866.3415 Section 866.3415 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES..., abscesses, and meningitis (inflammation of brain membranes). Pseudomonas pseudomallei causes melioidosis,...

  3. 21 CFR 866.3415 - Pseudomonas spp. serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Pseudomonas spp. serological reagents. 866.3415 Section 866.3415 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES..., abscesses, and meningitis (inflammation of brain membranes). Pseudomonas pseudomallei causes melioidosis,...

  4. 21 CFR 866.3415 - Pseudomonas spp. serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Pseudomonas spp. serological reagents. 866.3415 Section 866.3415 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES..., abscesses, and meningitis (inflammation of brain membranes). Pseudomonas pseudomallei causes melioidosis,...

  5. 21 CFR 866.3415 - Pseudomonas spp. serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Pseudomonas spp. serological reagents. 866.3415 Section 866.3415 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES..., abscesses, and meningitis (inflammation of brain membranes). Pseudomonas pseudomallei causes melioidosis,...

  6. Isolation and identification of Pseudomonas spp. from Schirmacher Oasis, Antarctica.

    PubMed Central

    Shivaji, S; Rao, N S; Saisree, L; Sheth, V; Reddy, G S; Bhargava, P M

    1989-01-01

    Ten cultures of Pseudomonas spp. were established from soil samples collected in and around a lake in Antarctica. Based on their morphology, biochemical and physiological characteristics, and moles percent G + C of their DNA, they were identified as P. fluorescens, P. putida, and P. syringae. This is the first report on the identification of Pseudomonas spp. from continental Antarctica. PMID:2930174

  7. Pseudomonas Exotoxin A: optimized by evolution for effective killing

    PubMed Central

    Michalska, Marta; Wolf, Philipp

    2015-01-01

    Pseudomonas Exotoxin A (PE) is the most toxic virulence factor of the pathogenic bacterium Pseudomonas aeruginosa. This review describes current knowledge about the intoxication pathways of PE. Moreover, PE represents a remarkable example for pathoadaptive evolution, how bacterial molecules have been structurally and functionally optimized under evolutionary pressure to effectively impair and kill their host cells. PMID:26441897

  8. Antibiofilm Activity of the Marine Bacterium Pseudoalteromonas sp. Strain 3J6▿

    PubMed Central

    Dheilly, Alexandra; Soum-Soutéra, Emmanuelle; Klein, Géraldine L.; Bazire, Alexis; Compère, Chantal; Haras, Dominique; Dufour, Alain

    2010-01-01

    Biofilm formation results in medical threats or economic losses and is therefore a major concern in a variety of domains. In two-species biofilms of marine bacteria grown under dynamic conditions, Pseudoalteromonas sp. strain 3J6 formed mixed biofilms with Bacillus sp. strain 4J6 but was largely predominant over Paracoccus sp. strain 4M6 and Vibrio sp. strain D01. The supernatant of Pseudoalteromonas sp. 3J6 liquid culture (SN3J6) was devoid of antibacterial activity against free-living Paracoccus sp. 4M6 and Vibrio sp. D01 cells, but it impaired their ability to grow as single-species biofilms and led to higher percentages of nonviable cells in 48-h biofilms. Antibiofilm molecules of SN3J6 were able to coat the glass surfaces used to grow biofilms and reduced bacterial attachment about 2-fold, which might partly explain the biofilm formation defect but not the loss of cell viability. SN3J6 had a wide spectrum of activity since it affected all Gram-negative marine strains tested except other Pseudoalteromonas strains. Biofilm biovolumes of the sensitive strains were reduced 3- to 530-fold, and the percentages of nonviable cells were increased 3- to 225-fold. Interestingly, SN3J6 also impaired biofilm formation by three strains belonging to the human-pathogenic species Pseudomonas aeruginosa, Salmonella enterica, and Escherichia coli. Such an antibiofilm activity is original and opens up a variety of applications for Pseudoalteromonas sp. 3J6 and/or its active exoproducts in biofilm prevention strategies. PMID:20363799

  9. Biotransformation of myrcene by Pseudomonas aeruginosa

    PubMed Central

    2011-01-01

    Background Dihydrolinalool and terpineol are sources of fragrances that provide a unique volatile terpenoid alcohol of low toxicity and thus are widely used in the perfumery industry, in folk medicine, and in aromatherapy. They are important chemical constituents of the essential oil of many plants. Previous studies have concerned the biotransformation of limonene by Pseudomonas putida. The objective of this research was to study biotransformation of myrcene by Pseudomonas aeruginosa. The culture preparation was done using such variables as different microbial methods and incubation periods to obtain maximum cells of P. aeruginosa for myrcene biotransformation. Results It was found that myrcene was converted to dihydrolinalool and 2,6-dimethyloctane in high percentages. The biotransformation products were identified by Fourier-transform infrared spectroscopy (FT-IR), ultraviolet (UV) analysis, gas chromatography (GC), and gas chromatography-mass spectroscopy (GC-MS). Comparison of the different incubation times showed that 3 days was more effective, the major products being 2,6-dimethyloctane (90.0%) and α-terpineol (7.7%) and comprising 97.7%. In contrast, the main compounds derived for an incubation time of 1.5 days were dihydrolinalool (79.5%) and 2,6-dimethyloctane (9.3%), with a total yield of 88.8%. PMID:21609445

  10. Ethylene Glycol Metabolism by Pseudomonas putida

    PubMed Central

    Mückschel, Björn; Simon, Oliver; Klebensberger, Janosch; Graf, Nadja; Rosche, Bettina; Altenbuchner, Josef; Pfannstiel, Jens; Huber, Armin

    2012-01-01

    In this study, we investigated the metabolism of ethylene glycol in the Pseudomonas putida strains KT2440 and JM37 by employing growth and bioconversion experiments, directed mutagenesis, and proteome analysis. We found that strain JM37 grew rapidly with ethylene glycol as a sole source of carbon and energy, while strain KT2440 did not grow within 2 days of incubation under the same conditions. However, bioconversion experiments revealed metabolism of ethylene glycol by both strains, with the temporal accumulation of glycolic acid and glyoxylic acid for strain KT2440. This accumulation was further increased by targeted mutagenesis. The key enzymes and specific differences between the two strains were identified by comparative proteomics. In P. putida JM37, tartronate semialdehyde synthase (Gcl), malate synthase (GlcB), and isocitrate lyase (AceA) were found to be induced in the presence of ethylene glycol or glyoxylic acid. Under the same conditions, strain KT2440 showed induction of AceA only. Despite this difference, the two strains were found to use similar periplasmic dehydrogenases for the initial oxidation step of ethylene glycol, namely, the two redundant pyrroloquinoline quinone (PQQ)-dependent enzymes PedE and PedH. From these results we constructed a new pathway for the metabolism of ethylene glycol in P. putida. Furthermore, we conclude that Pseudomonas putida might serve as a useful platform from which to establish a whole-cell biocatalyst for the production of glyoxylic acid from ethylene glycol. PMID:23023748

  11. Methylmercury degradation by Pseudomonas putida V1.

    PubMed

    Cabral, Lucélia; Yu, Ri-Qing; Crane, Sharron; Giovanella, Patricia; Barkay, Tamar; Camargo, Flávio A O

    2016-08-01

    Environmental contamination of mercury (Hg) has caused public health concerns with focuses on the neurotoxic substance methylmercury, due to its bioaccumulation and biomagnification in food chains. The goals of the present study were to examine: (i) the transformation of methylmercury, thimerosal, phenylmercuric acetate and mercuric chloride by cultures of Pseudomonas putida V1, (ii) the presence of the genes merA and merB in P. putida V1, and (iii) the degradation pathways of methylmercury by P. putida V1. Strain V1 cultures readily degraded methylmercury, thimerosal, phenylmercury acetate, and reduced mercuric chloride into gaseous Hg(0). However, the Hg transformation in LB broth by P. putida V1 was influenced by the type of Hg compounds. The merA gene was detected in P. putida V1, on the other hand, the merB gene was not detected. The sequencing of this gene, showed high similarity (100%) to the mercuric reductase gene of other Pseudomonas spp. Furthermore, tests using radioactive (14)C-methylmercury indicated an uncommon release of (14)CO2 concomitant with the production of Hg(0). The results of the present work suggest that P. putida V1 has the potential to remove methylmercury from contaminated sites. More studies are warranted to determine the mechanism of removal of methylmercury by P. putida V1.

  12. Mineralization of paraoxon and its use as a sole C and P source by a rationally designed catabolic pathway in Pseudomonas putida.

    PubMed

    de la Peña Mattozzi, Matthew; Tehara, Sundiep K; Hong, Thomas; Keasling, Jay D

    2006-10-01

    Organophosphate compounds, which are widely used as pesticides and chemical warfare agents, are cholinesterase inhibitors. These synthetic compounds are resistant to natural degradation and threaten the environment. We constructed a strain of Pseudomonas putida that can efficiently degrade a model organophosphate, paraoxon, and use it as a carbon, energy, and phosphorus source. This strain was engineered with the pnp operon from Pseudomonas sp. strain ENV2030, which encodes enzymes that transform p-nitrophenol into beta-ketoadipate, and with a synthetic operon encoding an organophosphate hydrolase (encoded by opd) from Flavobacterium sp. strain ATCC 27551, a phosphodiesterase (encoded by pde) from Delftia acidovorans, and an alkaline phosphatase (encoded by phoA) from Pseudomonas aeruginosa HN854 under control of a constitutive promoter. The engineered strain can efficiently mineralize up to 1 mM (275 mg/liter) paraoxon within 48 h, using paraoxon as the sole carbon and phosphorus source and an inoculum optical density at 600 nm of 0.03. Because the organism can utilize paraoxon as a sole carbon, energy, and phosphorus source and because one of the intermediates in the pathway (p-nitrophenol) is toxic at high concentrations, there is no need for selection pressure to maintain the heterologous pathway.

  13. Mineralization of Paraoxon and Its Use as a Sole C and P Source by a Rationally Designed Catabolic Pathway in Pseudomonas putida

    PubMed Central

    de la Peña Mattozzi, Matthew; Tehara, Sundiep K.; Hong, Thomas; Keasling, Jay D.

    2006-01-01

    Organophosphate compounds, which are widely used as pesticides and chemical warfare agents, are cholinesterase inhibitors. These synthetic compounds are resistant to natural degradation and threaten the environment. We constructed a strain of Pseudomonas putida that can efficiently degrade a model organophosphate, paraoxon, and use it as a carbon, energy, and phosphorus source. This strain was engineered with the pnp operon from Pseudomonas sp. strain ENV2030, which encodes enzymes that transform p-nitrophenol into β-ketoadipate, and with a synthetic operon encoding an organophosphate hydrolase (encoded by opd) from Flavobacterium sp. strain ATCC 27551, a phosphodiesterase (encoded by pde) from Delftia acidovorans, and an alkaline phosphatase (encoded by phoA) from Pseudomonas aeruginosa HN854 under control of a constitutive promoter. The engineered strain can efficiently mineralize up to 1 mM (275 mg/liter) paraoxon within 48 h, using paraoxon as the sole carbon and phosphorus source and an inoculum optical density at 600 nm of 0.03. Because the organism can utilize paraoxon as a sole carbon, energy, and phosphorus source and because one of the intermediates in the pathway (p-nitrophenol) is toxic at high concentrations, there is no need for selection pressure to maintain the heterologous pathway. PMID:17021221

  14. Biochemical basis of mercury remediation and bioaccumulation by Enterobacter sp. EMB21.

    PubMed

    Sinha, Arvind; Kumar, Sumit; Khare, Sunil Kumar

    2013-01-01

    The aims of this study were to isolate metal bioaccumulating bacterial strains and to study their applications in removal of environmental problematic heavy metals like mercury. Five bacterial strains belonging to genera Enterobacter, Bacillus, and Pseudomonas were isolated from oil-spilled soil. Among these, one of the strains Enterobacter sp. EMB21 showed mercury bioaccumulation inside the cells simultaneous to its bioremediation. The bioaccumulation of remediated mercury was confirmed by transmission electron microscopy and energy dispersive X-ray. The mercury-resistant loci in the Enterobacter sp. EMB21 cells were plasmid-mediated as confirmed by transformation of mercury-sensitive Escherichia coli DH5α by Enterobacter sp. EMB21 plasmid. Effect of different culture parameters viz-a-viz inoculum size, pH, carbon, and nitrogen source revealed that alkaline pH and presence of dextrose and yeast extract favored better remediation. The results indicated the usefulness of Enterobacter sp. EMB21 for the effective remediation of mercury in bioaccumulated form. The Enterobacter sp. EMB21 seems promising for heavy metal remediation wherein the remediated metal can be trapped inside the cells. The process can further be developed for the synthesis of valuable high-end functional alloy, nanoparticles, or metal conjugates from the metal being remediated.

  15. Antimicrobial and Antimycobacterial Activity of Cyclostellettamine Alkaloids from Sponge Pachychalina sp.

    PubMed Central

    de Oliveira, Jaine H. H. L.; Seleghim, Mirna H. R.; Timm, Christoph; Grube, Achim; Köck, Matthias; Nascimento, Gislene G.F.; Martins, Ana Claudia T.; Silva, Elissa G. O.; de Souza, Ana Olívia; Minarini, Paulo R. R.; Galetti, Fabio C. S.; Silva, Célio L.; Hajdu, Eduardo; Berlinck, Roberto G. S.

    2006-01-01

    Cyclostellettamines A – F (1 – 6) isolated from the sponge Pachychalina sp. and cyclostellettamines G - I, K and L (7 – 11) obtained by synthesis were evaluated in bioassays of antimicrobial activity against susceptible and antibiotic-resistant Staphylococcus aureus, Pseudomonas aeruginosa and antibiotic-susceptible Escherichia coli and Candida albicans, as well as in antimycobacterial activity against Mycobacterium tuberculosis H37Rv bioassays. The results obtained indicated that cyclostellettamines display different antimicrobial activity depending on the alkyl-chain size, suggesting that, if a mechanism-of action is implied, it is dependent on the distance between the two pyridinium moieties of cyclostellettamines.

  16. Strain- and Substrate-Dependent Redox Mediator and Electricity Production by Pseudomonas aeruginosa

    PubMed Central

    Bosire, Erick M.; Blank, Lars M.

    2016-01-01

    ABSTRACT Pseudomonas aeruginosa is an important, thriving member of microbial communities of microbial bioelectrochemical systems (BES) through the production of versatile phenazine redox mediators. Pure culture experiments with a model strain revealed synergistic interactions of P. aeruginosa with fermenting microorganisms whereby the synergism was mediated through the shared fermentation product 2,3-butanediol. Our work here shows that the behavior and efficiency of P. aeruginosa in mediated current production is strongly dependent on the strain of P. aeruginosa. We compared levels of phenazine production by the previously investigated model strain P. aeruginosa PA14, the alternative model strain P. aeruginosa PAO1, and the BES isolate Pseudomonas sp. strain KRP1 with glucose and the fermentation products 2,3-butanediol and ethanol as carbon substrates. We found significant differences in substrate-dependent phenazine production and resulting anodic current generation for the three strains, with the BES isolate KRP1 being overall the best current producer and showing the highest electrochemical activity with glucose as a substrate (19 μA cm−2 with ∼150 μg ml−1 phenazine carboxylic acid as a redox mediator). Surprisingly, P. aeruginosa PAO1 showed very low phenazine production and electrochemical activity under all tested conditions. IMPORTANCE Microbial fuel cells and other microbial bioelectrochemical systems hold great promise for environmental technologies such as wastewater treatment and bioremediation. While there is much emphasis on the development of materials and devices to realize such systems, the investigation and a deeper understanding of the underlying microbiology and ecology are lagging behind. Physiological investigations focus on microorganisms exhibiting direct electron transfer in pure culture systems. Meanwhile, mediated electron transfer with natural redox compounds produced by, for example, Pseudomonas aeruginosa might enable an

  17. SP-100 space reactor safety

    SciTech Connect

    Not Available

    1987-05-01

    The SP-100 space reactor power system is being developed to meet the large electrical power requirements of civilian and military missions planned for the 1990's and beyond. It will remove the restrictions on electrical power generation that have tended to limit missions and will enable the fuller exploration and utilization of space. This booklet describes the SP-100 space reactor power system and its development. Particular emphasis is given to safety. The design aand operational features as well as the design and safety review process that will assure that the SP-100 can be launched nd operated safely are described.

  18. Type IV pilus glycosylation mediates resistance of Pseudomonas aeruginosa to opsonic activities of the pulmonary surfactant protein A.

    PubMed

    Tan, Rommel M; Kuang, Zhizhou; Hao, Yonghua; Lee, Francis; Lee, Timothy; Lee, Ryan J; Lau, Gee W

    2015-04-01

    Pseudomonas aeruginosa is a major bacterial pathogen commonly associated with chronic lung infections in cystic fibrosis (CF). Previously, we have demonstrated that the type IV pilus (Tfp) of P. aeruginosa mediates resistance to antibacterial effects of pulmonary surfactant protein A (SP-A). Interestingly, P. aeruginosa strains with group I pilins are O-glycosylated through the TfpO glycosyltransferase with a single subunit of O-antigen (O-ag). Importantly, TfpO-mediated O-glycosylation is important for virulence in mouse lungs, exemplified by more frequent lung infection in CF with TfpO-expressing P. aeruginosa strains. However, the mechanism underlying the importance of Tfp glycosylation in P. aeruginosa pathogenesis is not fully understood. Here, we demonstrated one mechanism of increased fitness mediated by O-glycosylation of group 1 pilins on Tfp in the P. aeruginosa clinical isolate 1244. Using an acute pneumonia model in SP-A+/+ versus SP-A-/- mice, the O-glycosylation-deficient ΔtfpO mutant was found to be attenuated in lung infection. Both 1244 and ΔtfpO strains showed equal levels of susceptibility to SP-A-mediated membrane permeability. In contrast, the ΔtfpO mutant was more susceptible to opsonization by SP-A and by other pulmonary and circulating opsonins, SP-D and mannose binding lectin 2, respectively. Importantly, the increased susceptibility to phagocytosis was abrogated in the absence of opsonins. These results indicate that O-glycosylation of Tfp with O-ag specifically confers resistance to opsonization during host-mediated phagocytosis.

  19. Yersinia nurmii sp. nov.

    PubMed

    Murros-Kontiainen, Anna; Fredriksson-Ahomaa, Maria; Korkeala, Hannu; Johansson, Per; Rahkila, Riitta; Björkroth, Johanna

    2011-10-01

    This study was set up to identify three Gram-negative, rod-shaped strains originating from broiler meat packaged under a modified atmosphere. A polyphasic taxonomic approach, including multilocus sequence analysis (MLSA) of five genes (16S rRNA, glnA, gyrB, recA and HSP60), DNA-DNA reassociation between the closest phylogenetic neighbours and determination of relevant phenotypic properties, was applied. Phylogenetic analysis of the 16S rRNA gene sequences grouped these strains together and within the genus Yersinia. MLSA of the 16S rRNA gene and four housekeeping genes showed that the strains formed a monophyletic group separate from other Yersinia species in all phylogenetic trees constructed. The strains had a phenotypic profile different from those of other representatives of the genus Yersinia, but most similar to that of Yersinia ruckeri. Typical virulence markers for pathogenic Yersinia were not detected. Based on phylogenetic, phenotypic and DNA-DNA reassociation data, a novel species, Yersinia nurmii sp. nov., is proposed for the isolated strains. The type strain is APN3a-c(T) ( = DSM 22296(T)  = LMG 25213(T)).

  20. Plant perceptions of plant growth-promoting Pseudomonas.

    PubMed Central

    Preston, Gail M

    2004-01-01

    Plant-associated Pseudomonas live as saprophytes and parasites on plant surfaces and inside plant tissues. Many plant-associated Pseudomonas promote plant growth by suppressing pathogenic micro-organisms, synthesizing growth-stimulating plant hormones and promoting increased plant disease resistance. Others inhibit plant growth and cause disease symptoms ranging from rot and necrosis through to developmental dystrophies such as galls. It is not easy to draw a clear distinction between pathogenic and plant growth-promoting Pseudomonas. They colonize the same ecological niches and possess similar mechanisms for plant colonization. Pathogenic, saprophytic and plant growth-promoting strains are often found within the same species, and the incidence and severity of Pseudomonas diseases are affected by environmental factors and host-specific interactions. Plants are faced with the challenge of how to recognize and exclude pathogens that pose a genuine threat, while tolerating more benign organisms. This review examines Pseudomonas from a plant perspective, focusing in particular on the question of how plants perceive and are affected by saprophytic and plant growth-promoting Pseudomonas (PGPP), in contrast to their interactions with plant pathogenic Pseudomonas. A better understanding of the molecular basis of plant-PGPP interactions and of the key differences between pathogens and PGPP will enable researchers to make more informed decisions in designing integrated disease-control strategies and in selecting, modifying and using PGPP for plant growth promotion, bioremediation and biocontrol. PMID:15306406

  1. Screening for endophytic nitrogen-fixing bacteria in Brazilian sugar cane varieties used in organic farming and description of Stenotrophomonas pavanii sp. nov.

    PubMed

    Ramos, Patrícia L; Van Trappen, Stefanie; Thompson, Fabiano L; Rocha, Rafael C S; Barbosa, Heloiza R; De Vos, Paul; Moreira-Filho, Carlos A

    2011-04-01

    A Gram-negative, rod-shaped, non-spore-forming and nitrogen-fixing bacterium, designated ICB 89(T), was isolated from stems of a Brazilian sugar cane variety widely used in organic farming. 16S rRNA gene sequence analysis revealed that strain ICB 89(T) belonged to the genus Stenotrophomonas and was most closely related to Stenotrophomonas maltophilia LMG 958(T), Stenotrophomonas rhizophila LMG 22075(T), Stenotrophomonas nitritireducens L2(T), [Pseudomonas] geniculata ATCC 19374(T), [Pseudomonas] hibiscicola ATCC 19867(T) and [Pseudomonas] beteli ATCC 19861(T). DNA-DNA hybridization together with chemotaxonomic data and biochemical characteristics allowed the differentiation of strain ICB 89(T) from its nearest phylogenetic neighbours. Therefore, strain ICB 89(T) represents a novel species, for which the name Stenotrophomonas pavanii sp. nov. is proposed. The type strain is ICB 89(T) ( = CBMAI 564(T)  = LMG 25348(T)).

  2. Biofilm formation and cellulose expression among diverse environmental Pseudomonas isolates.

    PubMed

    Ude, Susanne; Arnold, Dawn L; Moon, Christina D; Timms-Wilson, Tracey; Spiers, Andrew J

    2006-11-01

    The ability to form biofilms is seen as an increasingly important colonization strategy among both pathogenic and environmental bacteria. A survey of 185 plant-associated, phytopathogenic, soil and river Pseudomonas isolates resulted in 76% producing biofilms at the air-liquid (A-L) interface after selection in static microcosms. Considerable variation in biofilm phenotype was observed, including waxy aggregations, viscous and floccular masses, and physically cohesive biofilms with continuously varying strengths over 1500-fold. Calcofluor epifluorescent microscopy identified cellulose as the matrix component in biofilms produced by Pseudomonas asplenii, Pseudomonas corrugata, Pseudomonas fluorescens, Pseudomonas marginalis, Pseudomonas putida, Pseudomonas savastanoi and Pseudomonas syringae isolates. Cellulose expression and biofilm formation could be induced by the constitutively active WspR19 mutant of the cyclic-di-GMP-associated, GGDEF domain-containing response regulator involved in the P. fluorescens SBW25 wrinkly spreader phenotype and cellular aggregation in Pseudomonas aeruginosa PA01. WspR19 could also induce P. putida KT2440, which otherwise did not produce a biofilm or express cellulose, as well as Escherichia coli K12 and Salmonella typhimurium LT2, both of which express cellulose yet lack WspR homologues. Statistical analysis of biofilm parameters suggest that biofilm development is a more complex process than that simply described by the production of attachment and matrix components and bacterial growth. This complexity was also seen in multivariate analysis as a species-ecological habitat effect, underscoring the fact that in vitro biofilms are abstractions of those surface and volume colonization processes used by bacteria in their natural environments.

  3. Isolation and characterization of group II introns from Pseudomonas alcaligenes and Pseudomonas putida.

    PubMed

    Yeo, C C; Yiin, S; Tan, B H; Poh, C L

    2001-05-01

    Group II introns isolated from Pseudomonas alcaligenes NCIB 9867, Pseudomonas putida NCIB 9869, and P. putida KT2440 were closely related with nucleotide sequence identities of between 87 and 96%. The genome of P. alcaligenes also harbored a truncated group II intron of 682 bp that lacks the gene for the intron-encoded protein (IEP). Unlike most bacterial group II introns, the Pseudomonas introns were found to lack the Zn domains in their IEPs, did not appear to interrupt any genes, and were located downstream of open reading frames which were adjacent to hairpin loop structures that resemble rho-independent terminators. These structures also contain the intron binding sites 1 and 2 (IBS1 and IBS2 sequences) that were required for intron target site recognition in transposition. One of the group II introns found in P. alcaligenes, Xln3, was shown to have transposed from the chromosome to the endogenous pRA2 plasmid at a site adjacent to IBS1- and IBS2-like sequences.

  4. Biosynthesis of Gold Nanoparticles Using Fusarium oxysporum f. sp. cubense JT1, a Plant Pathogenic Fungus

    PubMed Central

    Thakker, Janki N.; Dalwadi, Pranay; Dhandhukia, Pinakin C.

    2013-01-01

    The development of reliable processes for the synthesis of gold nanoparticles is an important aspect of current nanotechnology research. Recently, reports are published on the extracellular as well as intracellular biosynthesis of gold nanoparticles using microorganisms. However, these methods of synthesis are rather slow. In present study, rapid and extracellular synthesis of gold nanoparticles using a plant pathogenic fungus F. oxysporum f. sp. cubense JT1 (FocJT1) is reported. Incubation of FocJT1 mycelium with auric chloride solution produces gold nanoparticles in 60 min. Gold nanoparticles were characterized by UV-Vis spectroscopy, FTIR, and particle size analysis. The particles synthesized were of 22 nm sized, capped by proteins, and posed antimicrobial activity against Pseudomonas sp. PMID:25969773

  5. Crude oil biodegradation aided by biosurfactants from Pseudozyma sp. NII 08165 or its culture broth.

    PubMed

    Sajna, Kuttuvan Valappil; Sukumaran, Rajeev Kumar; Gottumukkala, Lalitha Devi; Pandey, Ashok

    2015-09-01

    The aim of this work was to evaluate the biosurfactants produced by the yeast Pseudozyma sp. NII 08165 for enhancing the degradation of crude oil by a model hydrocarbon degrading strain, Pseudomonas putida MTCC 1194. Pseudozyma biosurfactants were supplemented at various concentrations to the P. putida culture medium containing crude oil as sole carbon source. Supplementation of the biosurfactants enhanced the degradation of crude oil by P. putida; the maximum degradation of hydrocarbons was observed with a 2.5 mg L(-1) supplementation of biosurfactants. Growth inhibition constant of the Pseudozyma biosurfactants was 11.07 mg L(-1). It was interesting to note that Pseudozyma sp. NII 08165 alone could also degrade diesel and kerosene. Culture broth of Pseudozyma containing biosurfactants resulted up to ∼46% improvement in degradation of C10-C24 alkanes by P. putida. The enhancement in degradation efficiency of the bacterium with the culture broth supplementation was even more pronounced than that with relatively purer biosurfactants.

  6. Actinoplanes couchii sp. nov.

    PubMed

    Kämpfer, Peter; Huber, Birgit; Thummes, Kathrin; Grün-Wollny, Iris; Busse, Hans-Jürgen

    2007-04-01

    A Gram-positive bacterium, strain GW8-1761(T), was isolated from soil close to the Marmore waterfalls, Terni, Italy. 16S rRNA gene sequence similarity studies showed that strain GW8-1761(T) belonged to the genus Actinoplanes, being most closely related to Actinoplanes italicus JCM 3165(T) (98.9 %), A. rectilineatus IFO 13941(T) (98.5 %), A. palleronii JCM 7626(T) (97.8 %), A. utahensis IFO 13244(T) (97.6 %) and A. cyaneus DSM 46137(T) (97.6 %). Strain GW8-1761(T) could be distinguished from any other Actinoplanes species with validly published names by 16S rRNA gene sequence similarity values of less than 97.5 %. Chemotaxonomic data [major menaquinone MK-9(H(4)); major polar lipids diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol, with phosphatidylcholine and aminoglycolipids absent; major fatty acids C(15 : 0), C(16 : 0), C(16 : 0) iso, C(17 : 1)omega8c and summed feature 3 (C(16 : 1)omega7c and/or C(15 : 0) iso 2-OH)] supported the affiliation of strain GW8-1761(T) to the genus Actinoplanes. The results of DNA-DNA hybridizations and physiological and biochemical tests allowed genotypic and phenotypic differentiation of strain GW8-1761(T) from the most closely related species. Strain GW8-1761(T) therefore merits species status, and we propose the name Actinoplanes couchii sp. nov., with the type strain GW8-1761(T) (=DSM 45050(T)=CIP 109316(T)).

  7. Occurrence of Pseudomonas aeruginosa in Kuwait soil.

    PubMed

    Al-Saleh, Esmaeil; Akbar, Abrar

    2015-02-01

    Environmentally ubiquitous bacteria such as Pseudomonas aeruginosa evolved mechanisms to adapt and prevail under diverse conditions. In the current investigation, strains of P. aeruginosa demonstrating high rates of crude oil utilization and tolerance to high concentrations of heavy metals were found in both crude oil-contaminated and uncontaminated sites in Kuwait, and were dominant in the contaminated sites. The incidence of P. aeruginosa in tested soils implies the definitive pattern of crude oil contamination in the selection of the bacterial population in petroleum-contaminated sites in Kuwait. Surprisingly, the unculturable P. aeruginosa in different soil samples showed significant high similarity coefficients based on 16S-RFLP analyses, implying that the unculturable fraction of existing bacterial population in environmental samples is more stable and, hence, reliable for phylogenetic studies compared to the culturable bacteria.

  8. The Accessory Genome of Pseudomonas aeruginosa

    PubMed Central

    Kung, Vanderlene L.; Ozer, Egon A.; Hauser, Alan R.

    2010-01-01

    Summary: Pseudomonas aeruginosa strains exhibit significant variability in pathogenicity and ecological flexibility. Such interstrain differences reflect the dynamic nature of the P. aeruginosa genome, which is composed of a relatively invariable “core genome” and a highly variable “accessory genome.” Here we review the major classes of genetic elements comprising the P. aeruginosa accessory genome and highlight emerging themes in the acquisition and functional importance of these elements. Although the precise phenotypes endowed by the majority of the P. aeruginosa accessory genome have yet to be determined, rapid progress is being made, and a clearer understanding of the role of the P. aeruginosa accessory genome in ecology and infection is emerging. PMID:21119020

  9. Pseudomonas aeruginosa ventilator-associated pneumonia management.

    PubMed

    Ramírez-Estrada, Sergio; Borgatta, Bárbara; Rello, Jordi

    2016-01-01

    Ventilator-associated pneumonia is the most common infection in intensive care unit patients associated with high morbidity rates and elevated economic costs; Pseudomonas aeruginosa is one of the most frequent bacteria linked with this entity, with a high attributable mortality despite adequate treatment that is increased in the presence of multiresistant strains, a situation that is becoming more common in intensive care units. In this manuscript, we review the current management of ventilator-associated pneumonia due to P. aeruginosa, the most recent antipseudomonal agents, and new adjunctive therapies that are shifting the way we treat these infections. We support early initiation of broad-spectrum antipseudomonal antibiotics in present, followed by culture-guided monotherapy de-escalation when susceptibilities are available. Future management should be directed at blocking virulence; the role of alternative strategies such as new antibiotics, nebulized treatments, and vaccines is promising.

  10. Pseudomonas aeruginosa ventilator-associated pneumonia management

    PubMed Central

    Ramírez-Estrada, Sergio; Borgatta, Bárbara; Rello, Jordi

    2016-01-01

    Ventilator-associated pneumonia is the most common infection in intensive care unit patients associated with high morbidity rates and elevated economic costs; Pseudomonas aeruginosa is one of the most frequent bacteria linked with this entity, with a high attributable mortality despite adequate treatment that is increased in the presence of multiresistant strains, a situation that is becoming more common in intensive care units. In this manuscript, we review the current management of ventilator-associated pneumonia due to P. aeruginosa, the most recent antipseudomonal agents, and new adjunctive therapies that are shifting the way we treat these infections. We support early initiation of broad-spectrum antipseudomonal antibiotics in present, followed by culture-guided monotherapy de-escalation when susceptibilities are available. Future management should be directed at blocking virulence; the role of alternative strategies such as new antibiotics, nebulized treatments, and vaccines is promising. PMID:26855594

  11. Osmoregulation in Pseudomonas aeruginosa under hyperosmotic shock.

    PubMed

    Velasco, R; Burgoa, R; Flores, E; Hernández, E; Villa, A; Vaca, S

    1995-01-01

    Pseudomonas aeruginosa PAO1 strain was found to be able to tolerate 700 mM NaCl. 0.5 mM of the osmoprotectant betaine restablished the growth of this strain in 1200 mM NaCl. Intracellular K+ and glutamate concentrations of P. aeruginosa PAO1 after an hyperosmotic shock (400 mM NaCl) showed a permanent increase. Adition of betaine (0.5 mM) to the medium with NaCl had an inhibitory effect on the intracellular accumulation of glutamate. The results indicate that P. aeruginosa PAO1 resists high NaCl concentrations, K+ accumulation and glutamate synthesis probably being the first mechanisms involved in adaptation to osmotic stress. Also is is demonstrated that betaine modulates intracellular glutamate levels in osmotically stressed P. aeruginosa PAO1.

  12. Fluoranthene degradation in Pseudomonas alcaligenes PA-10.

    PubMed

    Gordon, L; Dobson, A D

    2001-01-01

    Pseudomonas alcaligenes strain PA-10 degrades the four-ring polycyclic aromatic hydrocarbon fluoranthene, co-metabolically. HPLC analysis of the growth medium identified four intermediates, 9-fluorenone-1-carboxylic acid; 9-hydroxy-1-fluorene carboxylic acid; 9-fluorenone and 9-fluorenol, formed during fluoranthene degradation. Pre-exposure of PA-10 to 9-fluorenone-1-carboxylic acid and 9-hydroxy-1-fluorene-carboxylic acid resulted in increases in fluoranthene removal, while pre-exposure to 9-fluorenone and 9-fluorenol resulted in a decrease in fluoranthene degradation. The rate of indole transformation was similarly affected by pre-exposure to these metabolic intermediates, indicating a link between fluoranthene degradation and indigo formation in this strain.

  13. Thermal mitigation of Pseudomonas aeruginosa biofilms

    PubMed Central

    O’Toole, Ann; Ricker, Erica B.; Nuxoll, Eric

    2015-01-01

    Bacterial biofilms infect 2 – 4 % of medical devices upon implantation, resulting in multiple surgeries and increased recovery time due to the very great increase in antibiotic resistance in the biofilm phenotype. This work investigates the feasibility of thermal mitigation of biofilms at physiologically accessible temperatures. Pseudomonas aeruginosa biofilms were cultured to high bacterial density (1.7 × 109 CFU cm−2) and subjected to thermal shocks ranging from 50 °C to 80 °C for durations of 1 to 30 min. The decrease in viable bacteria was closely correlated with an Arrhenius temperature dependence and Weibull-style time dependence, demonstrating up to six orders of magnitude reduction in bacterial load. The bacterial load for films with more conventional initial bacterial densities dropped below quantifiable levels, indicating thermal mitigation as a viable approach to biofilm control. PMID:26371591

  14. Pseudomonas aeruginosa Dose-Response and Bathing Water Infection

    EPA Science Inventory

    Pseudomonas aeruginosa is the most commonly identified opportunistic pathogen associated with pool acquired bather disease. To better understand why this microorganism poses this protracted problem we recently appraised P. aeruginosa pool risk management. Much is known about the ...

  15. Pseudomonas Folliculitis Associated with Use of Hot Tubs and Spas.

    ERIC Educational Resources Information Center

    Ramsey, Michael L.

    1989-01-01

    Discusses the history, etiology, diagnosis, histopathology, treatment, and prevention of Pseudomonas Folliculitis, an increasingly common skin infection contracted in hot tubs and, to some extent, in swimming pools. (Author/SM)

  16. Isolation of oxidase-negative Pseudomonas aeruginosa from sputum culture.

    PubMed

    Hampton, K D; Wasilauskas, B L

    1979-05-01

    Two isolates of Pseudomonas aeruginosa lacking characteristic indophenol oxidase were recovered from a sputum specimen. A discussion of the characteristic biochemical tests and antibiograms along with a possible explanation for this phenomenon is presented.

  17. Effect of Vincristine Sulfate on Pseudomonas Infections in Monkeys

    PubMed Central

    Saslaw, Samuel; Carlisle, Harold N.; Moheimani, Mohammad

    1972-01-01

    In rhesus monkeys, intravenous challenge with 0.6 × 1010 to 2.2 × 1010Pseudomonas aeruginosa organisms caused acute illness of 4 to 5 days' duration with spontaneous recovery in 13 of 15 monkeys; blood cultures became negative 3 to 17 days after challenge. Leukocytosis was observed in all monkeys. Intravenous or intratracheal inoculation of 2.0 to 2.5 mg of vincristine sulfate was followed by leukopenia in 4 to 5 days. Intravenous inoculation of 4.2 × 1010 to 7.8 × 1010 pyocin type 6 Pseudomonas organisms in monkeys given vincristine sulfate 4 days previously resulted in fatal infection in 11 of 14 monkeys, whereas none of four receiving Pseudomonas alone died. These studies suggest that an antimetabolite-induced leukopenia predisposes to severe Pseudomonas sepsis and that such monkeys may serve as a biological model for study of comparative efficacy of antimicrobial agents. PMID:4631913

  18. New strategies for genetic engineering Pseudomonas syringae using recombination

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Here we report that DNA oligonucleotides (oligos) introduced directly into bacteria by electroporation can recombine with the bacterial chromosome. This phenomenon was identified in Pseudomonas syringae and we subsequently found that Escherichia coli, Salmonella typhimurium and Shigella flexneri are...

  19. Genetic construction of recombinant Pseudomonas chlororaphis for improved glycerol utilization

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study is to improve by genetic engineering the glycerol metabolic capability of Pseudomonas chlororaphis which is capable of producing commercially valuable biodegradable poly(hydroxyalkanoate) (PHA) and biosurfactant rhamnolipids (RLs). In the study, glycerol uptake facilitat...

  20. Description of Pelomonas aquatica sp. nov. and Pelomonas puraquae sp. nov., isolated from industrial and haemodialysis water.

    PubMed

    Gomila, Margarita; Bowien, Botho; Falsen, Enevold; Moore, Edward R B; Lalucat, Jorge

    2007-11-01

    Three Gram-negative, rod-shaped, non-spore-forming bacteria (strains CCUG 52769T, CCUG 52770 and CCUG 52771) isolated from haemodialysis water were characterized taxonomically, together with five strains isolated from industrial waters (CCUG 52428, CCUG 52507, CCUG 52575T, CCUG 52590 and CCUG 52631). Phylogenetic analysis based on 16S rRNA gene sequences indicated that these isolates belonged to the class Betaproteobacteria and were related to the genus Pelomonas, with 16S rRNA gene sequence similarities higher than 99% with the only species of the genus, Pelomonas saccharophila and to Pseudomonas sp. DSM 2583. The type strains of Mitsuaria chitosanitabida and Roseateles depolymerans were their closest neighbours (97.9 and 97.3% 16S rRNA gene sequence similarity, respectively). Phylogenetic analysis was also performed for the internally transcribed spacer region and for three genes [hoxG (hydrogenase), cbbL/cbbM (Rubisco) and nifH (nitrogenase)] relevant for the metabolism of the genus Pelomonas. DNA-DNA hybridization, major fatty acid composition and phenotypical analyses were carried out, which included the type strain of Pelomonas saccharophila obtained from different culture collections (ATCC 15946T, CCUG 32988T, DSM 654T, IAM 14368T and LMG 2256T), as well as M. chitosanitabida IAM 14711T and R. depolymerans CCUG 52219T. Results of DNA-DNA hybridization, physiological and biochemical tests supported the conclusion that strains CCUG 52769, CCUG 52770 and CCUG 52771 represent a homogeneous phylogenetic and genomic group, including strain DSM 2583, clearly differentiated from the industrial water isolates and from the Pelomonas saccharophila type strain. On the basis of phenotypic and genotypic characteristics, these strains belong to two novel species within the genus Pelomonas, for which the names Pelomonas puraquae sp. nov. and Pelomonas aquatica sp. nov. are proposed. The type strains of Pelomonas puraquae sp. nov. and Pelomonas aquatica sp. nov. are CCUG

  1. Tracing of Two Pseudomonas Strains in the Root and Rhizoplane of Maize, as Related to Their Plant Growth-Promoting Effect in Contrasting Soils

    PubMed Central

    Mosimann, Carla; Oberhänsli, Thomas; Ziegler, Dominik; Nassal, Dinah; Kandeler, Ellen; Boller, Thomas; Mäder, Paul; Thonar, Cécile

    2017-01-01

    TaqMan-based quantitative PCR (qPCR) assays were developed to study the persistence of two well-characterized strains of plant growth-promoting rhizobacteria (PGPR), Pseudomonas fluorescens Pf153 and Pseudomonas sp. DSMZ 13134, in the root and rhizoplane of inoculated maize plants. This was performed in pot experiments with three contrasting field soils (Buus, Le Caron and DOK-M). Potential cross-reactivity of the qPCR assays was assessed with indigenous Pseudomonas and related bacterial species, which had been isolated from the rhizoplane of maize roots grown in the three soils and then characterized by Matrix-Assisted Laser Desorption Ionization (MALDI) Time-of-Flight (TOF) mass spectrometry (MS). Sensitivity of the qPCR expressed as detection limit of bacterial cells spiked into a rhizoplane matrix was 1.4 × 102 CFU and 1.3 × 104 CFU per gram root fresh weight for strain Pf153 and DSMZ 13134, respectively. Four weeks after planting and inoculation, both strains could readily be detected in root and rhizoplane, whereas only Pf153 could be detected after 8 weeks. The colonization rate of maize roots by strain Pf153 was significantly influenced by the soil type, with a higher colonization rate in the well fertile and organic soil of Buus. Inoculation with strain DSMZ 13134, which colonized roots and rhizoplane to the same degree, independently of the soil type, increased yield of maize, in terms of biomass accumulation, only in the acidic soil of Le Caron, whereas inoculation with strain Pf153 reduced yield in the soil Buus, despite of its high colonization rate and persistence. These results indicate that the colonization rate and persistence of inoculated Pseudomonas strains can be quantitatively assessed by the TaqMan-based qPCR technique, but that it cannot be taken for granted that inoculation with a well-colonizing and persistent Pseudomonas strain has a positive effect on yield of maize. PMID:28119675

  2. Endophytic bacteria from Piper tuberculatum Jacq.: isolation, molecular characterization, and in vitro screening for the control of Fusarium solani f. sp piperis, the causal agent of root rot disease in black pepper (Piper nigrum L.).

    PubMed

    Nascimento, S B; Lima, A M; Borges, B N; de Souza, C R B

    2015-07-06

    Endophytic bacteria have been found to colonize internal tissues in many different plants, where they can have several beneficial effects, including defense against pathogens. In this study, we aimed to identify endophytic bacteria associated with roots of the tropical piperaceae Piper tuberculatum, which is known for its resistance to infection by Fusarium solani f. sp piperis, the causal agent of black pepper (Piper nigrum) root rot disease in the Amazon region. Based on 16S rRNA gene sequence analysis, we isolated endophytes belonging to 13 genera: Bacillus, Paenibacillus, Pseudomonas, Enterobacter, Rhizobium, Sinorhizobium, Agrobacterium, Ralstonia, Serratia, Cupriavidus, Mitsuaria, Pantoea, and Staphylococcus. The results showed that 56.52% of isolates were associated with the phylum Proteobacteria, which comprised α, β, and γ classes. Other bacteria were related to the phylum Firmicutes, including Bacillus, which was the most abundant genus among all isolates. Antagonistic assays revealed that Pt12 and Pt13 isolates, identified as Pseudomonas putida and Pseudomonas sp, respectively, were able to inhibit F. solani f. sp piperis growth in vitro. We describe, for the first time, the molecular identification of 23 endophytic bacteria from P. tuberculatum, among which two Pseudomonas species have the potential to control the pathogen responsible for root rot disease in black pepper in the Amazon region.

  3. Spoilage potential of Pseudomonas species isolated from goat milk.

    PubMed

    Scatamburlo, T M; Yamazi, A K; Cavicchioli, V Q; Pieri, F A; Nero, L A

    2015-02-01

    Pseudomonas spp. are usually associated with spoilage microflora of dairy products due to their proteolytic potential. This is of particular concern for protein-based products, such as goat milk cheeses and fermented milks. Therefore, the goal of the present study was to characterize the proteolytic activity of Pseudomonas spp. isolated from goat milk. Goat milk samples (n=61) were obtained directly from bulk tanks on dairy goat farms (n=12), and subjected to a modified International Organization for Standardization (ISO) protocol to determine the number and proteolytic activity of Pseudomonas spp. Isolates (n=82) were obtained, identified by PCR, and subjected to pulsed-field gel electrophoresis with XbaI macro-restriction. Then, the isolates were subjected to PCR to detect the alkaline protease gene (apr), and phenotypic tests were performed to check proteolytic activity at 7°C, 25°C, and 35°C. Mean Pseudomonas spp. counts ranged from 2.9 to 4.8 log cfu/mL, and proteolytic Pseudomonas spp. counts ranged from 1.9 to 4.6 log cfu/mL. All isolates were confirmed to be Pseudomonas spp., and 41 were identified as Pseudomonas fluorescens, which clustered into 5 groups sharing approximately 82% similarity. Thirty-six isolates (46.9%) were positive for the apr gene; and 57 (69.5%) isolates presented proteolytic activity at 7°C, 82 (100%) at 25°C, and 64 (78%) at 35°C. The isolates were distributed ubiquitously in the goat farms, and no relationship among isolates was observed when the goat farms, presence of apr, pulsotypes, and proteolytic activity were taken into account. We demonstrated proteolytic activity of Pseudomonas spp. present in goat milk by phenotypic and genotypic tests and indicated their spoilage potential at distinct temperatures. Based on these findings and the ubiquity of Pseudomonas spp. in goat farm environments, proper monitoring and control of Pseudomonas spp. during production are critical.

  4. Strain identification and quorum sensing inhibition characterization of marine-derived Rhizobium sp. NAO1

    PubMed Central

    Chang, Hong; Zhu, Xiaoshan; Yu, Shenchen; Chen, Lu; Jin, Hui; Cai, Zhonghua

    2017-01-01

    A novel strategy for combating pathogens is through the ongoing development and use of anti-quorum sensing (QS) treatments such as therapeutic bacteria or their anti-QS substances. Relatively little is known about the bacteria that inhabit the open ocean and of their potential anti-pathogenic attributes; thus, in an initiative to identify these types of therapeutic bacteria, planktonic microbes from the North Atlantic Ocean were collected, isolated, cultured and screened for anti-QS activity. Screening analysis identified one such strain, Rhizobium sp. NAO1. Extracts of Rhizobium sp. NAO1 were identified via ultra-performance liquid chromatography (UPLC) analysis. They were shown to contain N-acyl homoserine lactone (AHL)-based QS analogues (in particular, the N-butyryl homoserine lactone (C4-AHL) analogue) and could disrupt biofilm formation by Pseudomonas aeruginosa PAO1. QS inhibition was confirmed using confocal scanning laser microscopy and growth curves, and it was shown to occur in a dose-dependent manner without affecting bacterial growth. Secondary metabolites of Rhizobium sp. NAO1 inhibited PAO1 pathogenicity by downregulating AHL-mediated virulence factors such as elastase activity and siderophore production. Furthermore, as a result of biofilm structure damage, the secondary metabolite products of Rhizobium sp. NAO1 significantly increased the sensitivity of PAO1 to aminoglycoside antibiotics. Our results demonstrated that Rhizobium sp. strain NAO1 has the ability to disrupt P. aeruginosa PAO1 biofilm architecture, in addition to attenuating P. aeruginosa PAO1 virulence factor production and pathogenicity. Therefore, the newly identified ocean-derived Rhizobium sp. NAO1 has the potential to serve as a QS inhibitor and may be a new microbial resource for drug development.

  5. Strategy of Pseudomonas pseudoalcaligenes C70 for effective degradation of phenol and salicylate

    PubMed Central

    Heinaru, Eeva; Naanuri, Eve; Mehike, Maris; Leito, Ivo; Heinaru, Ain

    2017-01-01

    Phenol- and naphthalene-degrading indigenous Pseudomonas pseudoalcaligenes strain C70 has great potential for the bioremediation of polluted areas. It harbours two chromosomally located catechol meta pathways, one of which is structurally and phylogenetically very similar to the Pseudomonas sp. CF600 dmp operon and the other to the P. stutzeri AN10 nah lower operon. The key enzymes of the catechol meta pathway, catechol 2,3-dioxygenase (C23O) from strain C70, PheB and NahH, have an amino acid identity of 85%. The metabolic and regulatory phenotypes of the wild-type and the mutant strain C70ΔpheB lacking pheB were evaluated. qRT-PCR data showed that in C70, the expression of pheB- and nahH-encoded C23O was induced by phenol and salicylate, respectively. We demonstrate that strain C70 is more effective in the degradation of phenol and salicylate, especially at higher substrate concentrations, when these compounds are present as a mixture; i.e., when both pathways are expressed. Moreover, NahH is able to substitute for the deleted PheB in phenol degradation when salicylate is also present in the growth medium. The appearance of a yellow intermediate 2-hydroxymuconic semialdehyde was followed by the accumulation of catechol in salicylate-containing growth medium, and lower expression levels and specific activities of the C23O of the sal operon were detected. However, the excretion of the toxic intermediate catechol to the growth medium was avoided when the growth medium was supplemented with phenol, seemingly due to the contribution of the second meta pathway encoded by the phe genes. PMID:28257519

  6. Functional redundancy in phenol and toluene degradation in Pseudomonas stutzeri strains isolated from the Baltic Sea.

    PubMed

    Heinaru, Eeva; Naanuri, Eve; Grünbach, Maarja; Jõesaar, Merike; Heinaru, Ain

    2016-09-01

    In the present study we describe functional redundancy of bacterial multicomponent monooxygenases (toluene monooxygenase (TMO) and toluene/xylene monooxygenase (XylAM) of TOL pathway) and cooperative genetic regulation at the expression of the respective catabolic operons by touR and xylR encoded regulatory circuits in five phenol- and toluene-degrading Pseudomonas stutzeri strains. In these strains both toluene degradation pathways (TMO and Xyl) are active and induced by toluene and phenol. The whole genome sequence of the representative strain 2A20 revealed the presence of complete TMO- and Xyl-upper pathway operons together with two sets of lower catechol meta pathway operons, as well as phenol-degrading operon in a single 292,430bp contig. The much lower GC content and analysis of the predicted ORFs refer to the plasmid origin of the approximately 130kb region of this contig, containing the xyl, phe and tou genes. The deduced amino acid sequences of the TMO, XylA and the large subunit of phenol monooxygenase (LmPH) show 98-100% identity with the respective gene products of the strain Pseudomonas sp. OX1. In both strains 2A20 and OX1 the meta-cleavage pathways for catechol degradation are coded by two redundant operons (phe and xyl). We show that in the strain 2A20 TouR and XylR are activated by different effector molecules, phenol and toluene, respectively, and they both control transcription of the xyl upper, tou (TMO) and phe catabolic operons. Although the growth parameters of redundant strains did not show advantage at toluene biodegradation, the functional redundancy could provide better flexibility to the bacteria in environmental conditions.

  7. Regulation of alkane oxidation in Pseudomonas putida.

    PubMed Central

    Grund, A; Shapiro, J; Fennewald, M; Bacha, P; Leahy, J; Markbreiter, K; Nieder, M; Toepfer, M

    1975-01-01

    We have studied the appearance of whole-cell oxidizing activity for n-alkanes and their oxidation products in strains of Pseudomonas putida carrying the OCT plasmid. Our results indicate that the OCT plasmid codes for inducible alkane-hydroxylating and primary alcohol-dehydrogenating activities and that the chromosome codes for constitutive oxidizing activities for primary alcohols, aliphatic aldehydes, and fatty acids. Mutant isolation confirms the presence of an alcohol dehydrogenase locus on the OCT plasmid and indicated the presence of multiple alcohol and aldehyde dehydrogenase loci on the P. putida chromosome. Induction tests with various compounds indicate that inducer recognition has specificity for chain length and can be affected by the degree of oxidation of the carbon chain. Some inducers are neither growth nor respiration substrates. Growth tests with and without a gratuitous inducer indicate that undecane is not a growth substrate because it does not induce alkane hydroxylase activity. Using a growth test for determining induction of the plasmid alcohol dehydrogenase it is possible to show that heptane induces this activity in hydroxylase-negative mutants. This suggests that unoxidized alkane molecules are the physiological inducers of both plasmid activities. PMID:1150626

  8. Secretion of phospholipase C by Pseudomonas aeruginosa.

    PubMed Central

    Stinson, M W; Hayden, C

    1979-01-01

    The conditions necessary for the secretion of phospholipase C (phosphatidylcholine cholinephosphohydrolase) by Pseudomonas aeruginosa were studied. Enzyme secretion by washed cell suspensions required a carbon source and ammonium, potassium, and calcium ions. The calcium requirement could be substituted by magnesium and strontium but not by copper, manganese, cobalt, or zinc. During growth in liquid medium, cells secreted phospholipase C during late logarithmic and early stationary phases. Secretion was repressed by the addition of inorganic phosphate but not by organic phosphates, glucose, or sodium succinate. Studies with tetracycline indicated that de novo protein synthesis was necessary for the secretion of phospholipase C and that the exoenzyme was not released from a preformed periplasmic pool. Similarly, extraction of actively secreting cells with 0.2 M MgCl2 at pH 8.4 solubilized large quantities of the periplasmic enzyme alkaline phosphatase but insignificant amounts of phospholipase C. Bacteria continued to secrete enzyme for nearly 45 min after the addition of inorganic phosphate or rifampin. Images PMID:114487

  9. Nitrite inhibition of denitrification by Pseudomonas fluorescens

    SciTech Connect

    Almeida, J.S.; Julio, S.M.; Reis, M.A.M. |

    1995-05-05

    Using a pure culture of Pseudomonas fluorescens as a model system nitrite inhibition of denitrification was studied. A mineral media with acetate and nitrate as sole electron donor and acceptor, respectively, was used. Results obtained in continuous stirred-tank reactors (CSTR) operated at pH values between 6.6 and 7.8 showed that growth inhibition depended only on the nitrite undissociated fraction concentration (nitrous acid). A mathematical model to describe this dependence is put forward. The maximum nitrous acid concentration compatible with cell growth and denitrification activity was found to be 66 {mu}g N/L. Denitrification activity was partially associated with growth, as described by the Luedeking-Piret equation. However, when the freshly inoculated reactor was operated discontinuously, nitrite accumulation caused growth uncoupling from denitrification activity. The authors suggest that these results can be interpreted considering that (a) nitrous acid acts as a proton uncoupler; and (b) cultures continuously exposed to nitrous acid prevent the uncoupling effect but not the growth inhibition. Examination of the growth dependence on nitrite concentration at pH 7.0 showed that adapted cultures (growth on CSTR) are less sensitive to nitrous acid inhibition than the ones cultivated in batch.

  10. Comprehensive transposon mutant library of Pseudomonas aeruginosa

    PubMed Central

    Jacobs, Michael A.; Alwood, Ashley; Thaipisuttikul, Iyarit; Spencer, David; Haugen, Eric; Ernst, Stephen; Will, Oliver; Kaul, Rajinder; Raymond, Christopher; Levy, Ruth; Chun-Rong, Liu; Guenthner, Donald; Bovee, Donald; Olson, Maynard V.; Manoil, Colin

    2003-01-01

    We have developed technologies for creating saturating libraries of sequence-defined transposon insertion mutants in which each strain is maintained. Phenotypic analysis of such libraries should provide a virtually complete identification of nonessential genes required for any process for which a suitable screen can be devised. The approach was applied to Pseudomonas aeruginosa, an opportunistic pathogen with a 6.3-Mbp genome. The library that was generated consists of 30,100 sequence-defined mutants, corresponding to an average of five insertions per gene. About 12% of the predicted genes of this organism lacked insertions; many of these genes are likely to be essential for growth on rich media. Based on statistical analyses and bioinformatic comparison to known essential genes in E. coli, we estimate that the actual number of essential genes is 300-400. Screening the collection for strains defective in two defined multigenic processes (twitching motility and prototrophic growth) identified mutants corresponding to nearly all genes expected from earlier studies. Thus, phenotypic analysis of the collection may produce essentially complete lists of genes required for diverse biological activities. The transposons used to generate the mutant collection have added features that should facilitate downstream studies of gene expression, protein localization, epistasis, and chromosome engineering. PMID:14617778

  11. Comprehensive transposon mutant library of Pseudomonas aeruginosa.

    PubMed

    Jacobs, Michael A; Alwood, Ashley; Thaipisuttikul, Iyarit; Spencer, David; Haugen, Eric; Ernst, Stephen; Will, Oliver; Kaul, Rajinder; Raymond, Christopher; Levy, Ruth; Chun-Rong, Liu; Guenthner, Donald; Bovee, Donald; Olson, Maynard V; Manoil, Colin

    2003-11-25

    We have developed technologies for creating saturating libraries of sequence-defined transposon insertion mutants in which each strain is maintained. Phenotypic analysis of such libraries should provide a virtually complete identification of nonessential genes required for any process for which a suitable screen can be devised. The approach was applied to Pseudomonas aeruginosa, an opportunistic pathogen with a 6.3-Mbp genome. The library that was generated consists of 30,100 sequence-defined mutants, corresponding to an average of five insertions per gene. About 12% of the predicted genes of this organism lacked insertions; many of these genes are likely to be essential for growth on rich media. Based on statistical analyses and bioinformatic comparison to known essential genes in E. coli, we estimate that the actual number of essential genes is 300-400. Screening the collection for strains defective in two defined multigenic processes (twitching motility and prototrophic growth) identified mutants corresponding to nearly all genes expected from earlier studies. Thus, phenotypic analysis of the collection may produce essentially complete lists of genes required for diverse biological activities. The transposons used to generate the mutant collection have added features that should facilitate downstream studies of gene expression, protein localization, epistasis, and chromosome engineering.

  12. Degradation of nitrobenzene by a Pseudomonas pseudoalcaligenes.

    PubMed Central

    Nishino, S F; Spain, J C

    1993-01-01

    A Pseudomonas pseudoalcaligenes able to use nitrobenzene as the sole source of carbon, nitrogen, and energy was isolated from soil and groundwater contaminated with nitrobenzene. The range of aromatic substrates able to support growth was limited to nitrobenzene, hydroxylaminobenzene, and 2-aminophenol. Washed suspensions of nitrobenzene-grown cells removed nitrobenzene from culture fluids with the concomitant release of ammonia. Nitrobenzene, nitrosobenzene, hydroxylaminobenzene, and 2-aminophenol stimulated oxygen uptake in resting cells and in extracts of nitrobenzene-grown cells. Under aerobic and anaerobic conditions, crude extracts converted nitrobenzene to 2-aminophenol with oxidation of 2 mol of NADPH. Ring cleavage, which required ferrous iron, produced a transient yellow product with a maximum A380. In the presence of NAD, the product disappeared and NADH was produced. In the absence of NAD, the ring fission product was spontaneously converted to picolinic acid, which was not further metabolized. These results indicate that the catabolic pathway involves the reduction of nitrobenzene to nitrosobenzene and then to hydroxylaminobenzene; each of these steps requires 1 mol of NADPH. An enzyme-mediated Bamberger-like rearrangement converts hydroxylaminobenzene to 2-aminophenol, which then undergoes meta ring cleavage to 2-aminomuconic semialdehyde. The mechanism for release of ammonia and subsequent metabolism are under investigation. PMID:8368838

  13. Chemotaxis by Pseudomonas syringae pv. tomato.

    PubMed

    Cuppels, Diane A

    1988-03-01

    Optimal laboratory conditions for studying chemotaxis by Pseudomonas syringae pv. tomato were determined by using the Adler capillary tube assay. Although they are not an absolute requirement for chemotaxis, the presence of 0.1 mM EDTA and 1 mM MgCl(2) in the chemotaxis buffer (10 mM potassium phosphate [pH 7.2]) significantly enhanced the response to attractant. The addition of mannitol as an energy source had little effect. The optimal temperature for chemotaxis was 23 degrees C, which is 5 degrees C below the optimal growth temperature for this pathogen. The best response occurred when the bacteria were exposed to attractant for 60 min at a concentration of approximately 5 x 10 CFU/ml. P. syringae pv. tomato was strongly attracted to citric and malic acids, which are the predominant organic acids in tomato fruit. With the exception of asparagine, the major amino acids of tomatoes were weak to moderate attractants. Glucose and fructose, which account for approximately 47% of tomato dry matter, also elicited poor responses. In assays with tomato intercellular fluid and leaf surface water, the bacterial speck pathogen could not chemotactically distinguish between a resistant and a susceptible cultivar of tomato.

  14. Effect of temperature on Pseudomonas fluorescens chemotaxis.

    PubMed

    Lynch, W H

    1980-07-01

    The effects of temperature and attractants on chemotaxis in psychrotrophic Pseudomonas fluorescens were examined using the Adler capillary assay technique. Several organic acids, amino acids, and uronic acids were shown to be attractants, whereas glucose and its oxidation products, gluconate and 2-ketogluconate, elicited no detectable response. Chemotaxis toward many attractants was dependent on prior growth of the microorganism with these compounds. However, the organic acids, malate and succinate, caused strong chemotactic responses regardless of the carbon source used for growth of the bacteria. The temperature at which the cells were grown (30 or 5 degrees C) had no significant detectable effect on chemotaxis to the above attractants. The temperature at which the cells were assayed appeared to affect the rate but the extent of the chemotactic response, nor the concentration response curves. The ratios of the rate of accumulation of cells to the attractant malate were approximately 2, 4, and 1 at 30, 17, and 5 degrees C, respectively. Strong chemotactic responses were observed with cells assayed at temperatures approaching 0 degree C and appeared to be functional over a broad temperature range of 3 to 35 degrees C.

  15. Purification of extracellular lipase from Pseudomonas aeruginosa.

    PubMed Central

    Stuer, W; Jaeger, K E; Winkler, U K

    1986-01-01

    Lipase (triacylglycerol acylhydrolase, EC 3.1.1.3) was excreted by Pseudomonas aeruginosa PAC1R during the late logarithmic growth phase. Characterization of cell-free culture supernatants by sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed the presence of significant amounts of lipopolysaccharide, part of which seemed to be tightly bound to lipase. After concentration of culture supernatants by ultrafiltration, lipase-lipopolysaccharide complexes were dissociated by treatment with EDTA-Tris buffer and subsequent sonication in the presence of the zwitterionic detergent 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate. The solubilized lipase was purified by isoelectric focusing in an agarose gel containing the same detergent; the lipase activity appeared in a single peak corresponding to a distinct band in the silver-stained gel. The isoelectric point was 5.8. Analysis of purified lipase by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and scanning revealed an apparent molecular weight of 29,000 and a specific activity of 760 mu kat/mg of protein. Estimations based on these data showed that a single P. aeruginosa cell excreted about 200 molecules of lipase, each having a molecular activity of 2.2 X 10(4) per s. Images PMID:3096967

  16. Regulation of Leucine Catabolism in Pseudomonas putida

    PubMed Central

    Massey, Linda K.; Conrad, Robert S.; Sokatch, John R.

    1974-01-01

    The generation time of Pseudomonas putida with l-leucine was 20 h in synthetic media but only 3 h with d-leucine. Slow growth in the presence of l-leucine was partially overcome by addition of 0.1 mM amounts of either d-valine, l-valine, or 2-ketoisovalerate. The activities of five enzymes which take part in the oxidation of leucine by P. putida were measured under various conditions of growth. Four enzymes were induced by growth with dl-leucine as sole source of carbon: d-amino acid dehydrogenase, branched-chain keto acid dehydrogenase, 3-methylcrotonyl-coenzyme A carboxylase, and 3-hydroxy-3-methylglutaryl-coenzyme A lyase. The segment of the pathway required for oxidation of 3-methylcrotonate was induced by growth on isovalerate or 3-methylcrotonate without formation of the preceding enzymes. The synthesis of carboxylase and lyase appeared to have been repressed by the addition of l-glutamate or glucose to cells growing on dl-leucine as the sole carbon source. Mutants unable to grow at the expense of isovalerate had reduced levels of carboxylase and lyase, whereas the levels of three enzymes common to the catabolism of all three branched-chain amino acids and those of two isoleucine catabolic enzymes were normal. PMID:4150714

  17. Evolutionary convergence in experimental Pseudomonas populations.

    PubMed

    Lind, Peter A; Farr, Andrew D; Rainey, Paul B

    2017-03-01

    Model microbial systems provide opportunity to understand the genetic bases of ecological traits, their evolution, regulation and fitness contributions. Experimental populations of Pseudomonas fluorescens rapidly diverge in spatially structured microcosms producing a range of surface-colonising forms. Despite divergent molecular routes, wrinkly spreader (WS) niche specialist types overproduce a cellulosic polymer allowing mat formation at the air-liquid interface and access to oxygen. Given the range of ways by which cells can form mats, such phenotypic parallelism is unexpected. We deleted the cellulose-encoding genes from the ancestral genotype and asked whether this mutant could converge on an alternate phenotypic solution. Two new traits were discovered. The first involved an exopolysaccharide encoded by pgaABCD that functions as cell-cell glue similar to cellulose. The second involved an activator of an amidase (nlpD) that when defective causes cell chaining. Both types form mats, but were less fit in competition with cellulose-based WS types. Surprisingly, diguanylate cyclases linked to cellulose overexpression underpinned evolution of poly-beta-1,6-N-acetyl-d-glucosamine (PGA)-based mats. This prompted genetic analyses of the relationships between the diguanylate cyclases WspR, AwsR and MwsR, and both cellulose and PGA. Our results suggest that c-di-GMP regulatory networks may have been shaped by evolution to accommodate loss and gain of exopolysaccharide modules facilitating adaptation to new environments.

  18. Developing an international Pseudomonas aeruginosa reference panel.

    PubMed

    De Soyza, Anthony; Hall, Amanda J; Mahenthiralingam, Eshwar; Drevinek, Pavel; Kaca, Wieslaw; Drulis-Kawa, Zuzanna; Stoitsova, Stoyanka R; Toth, Veronika; Coenye, Tom; Zlosnik, James E A; Burns, Jane L; Sá-Correia, Isabel; De Vos, Daniel; Pirnay, Jean-Paul; Kidd, Timothy J; Reid, David; Manos, Jim; Klockgether, Jens; Wiehlmann, Lutz; Tümmler, Burkhard; McClean, Siobhán; Winstanley, Craig

    2013-12-01

    Pseudomonas aeruginosa is a major opportunistic pathogen in cystic fibrosis (CF) patients and causes a wide range of infections among other susceptible populations. Its inherent resistance to many antimicrobials also makes it difficult to treat infections with this pathogen. Recent evidence has highlighted the diversity of this species, yet despite this, the majority of studies on virulence and pathogenesis focus on a small number of strains. There is a pressing need for a P. aeruginosa reference panel to harmonize and coordinate the collective efforts of the P. aeruginosa research community. We have collated a panel of 43 P. aeruginosa strains that reflects the organism's diversity. In addition to the commonly studied clones, this panel includes transmissible strains, sequential CF isolates, strains with specific virulence characteristics, and strains that represent serotype, genotype or geographic diversity. This focussed panel of P. aeruginosa isolates will help accelerate and consolidate the discovery of virulence determinants, improve our understanding of the pathogenesis of infections caused by this pathogen, and provide the community with a valuable resource for the testing of novel therapeutic agents.

  19. Pseudomonas biofilms: possibilities of their control.

    PubMed

    Masák, Jan; Čejková, Alena; Schreiberová, Olga; Rezanka, Tomáš

    2014-07-01

    Genus Pseudomonas includes a large number of species that can be encountered in biotechnological processes as well as in the role of serious human or plant pathogens. Pseudomonads easily form biofilms on various types of surfaces. The biofilm phenotype is characterized by an increased resistance to environmental influences including resistance to antibiotics and other disinfectants, causing a number of problems in health care, food industry, and other areas. Considerable attention is therefore paid to the possibilities of eradication/destruction of pseudomonads biofilms both in terms of understanding the mechanisms of biofilm formation and at the level of finding suitable antibiofilm tools applicable in practice. The first part of this review is devoted to an overview of the regulatory mechanisms that are directly or indirectly involved in the formation of biofilm. The most effective approaches to suppressing the formation of biofilm that do not cause the development of resistance are based on the application of substances that interfere with the regulatory molecules or block the appropriate regulatory mechanisms involved in biofilm development by the cells. Pseudomonads biofilm formation is, similar to other microorganisms, a sophisticated process with many regulatory elements. The suppression of this process therefore also requires multiple antibiofilm tools.

  20. Pseudomonas Aeruginosa: Resistance to the Max

    PubMed Central

    Poole, Keith

    2011-01-01

    Pseudomonas aeruginosa is intrinsically resistant to a variety of antimicrobials and can develop resistance during anti-pseudomonal chemotherapy both of which compromise treatment of infections caused by this organism. Resistance to multiple classes of antimicrobials (multidrug resistance) in particular is increasingly common in P. aeruginosa, with a number of reports of pan-resistant isolates treatable with a single agent, colistin. Acquired resistance in this organism is multifactorial and attributable to chromosomal mutations and the acquisition of resistance genes via horizontal gene transfer. Mutational changes impacting resistance include upregulation of multidrug efflux systems to promote antimicrobial expulsion, derepression of ampC, AmpC alterations that expand the enzyme's substrate specificity (i.e., extended-spectrum AmpC), alterations to outer membrane permeability to limit antimicrobial entry and alterations to antimicrobial targets. Acquired mechanisms contributing to resistance in P. aeruginosa include β-lactamases, notably the extended-spectrum β-lactamases and the carbapenemases that hydrolyze most β-lactams, aminoglycoside-modifying enzymes, and 16S rRNA methylases that provide high-level pan-aminoglycoside resistance. The organism's propensity to grow in vivo as antimicrobial-tolerant biofilms and the occurrence of hypermutator strains that yield antimicrobial resistant mutants at higher frequency also compromise anti-pseudomonal chemotherapy. With limited therapeutic options and increasing resistance will the untreatable P. aeruginosa infection soon be upon us? PMID:21747788

  1. Spaceflight Effects on Virulence of Pseudomonas Aeruginosa

    NASA Astrophysics Data System (ADS)

    Broadway, S.; Goins, T.; Crandell, C.; Richards, C.; Patel, M.; Pyle, B.

    2008-06-01

    Pseudomonas aeruginosa is an opportunistic pathogen found in the environment. It is known to infect the immunocompromised. The organism has about 25 virulence genes that play different roles in disease processes. Several exotoxin proteins may be produced, including ExoA, ExoS, ExoT and ExoY, and other virulence factors. In spaceflight, possible increased expression of P. aeruginosa virulence proteins could increase health risks for spaceflight crews who experience decreased immunity. Cultures of P. aeruginosa strains PA01 and PA103 grown on orbit on Shuttle Endeavour flight STS-123 vs. static ground controls were used for analysis. The production of ETA was quantitated using an ELISA procedure. Results showed that while flight cultures of PA103 produced slightly more ETA than corresponding ground controls, the opposite was found for PA01. While it appears that spaceflight has little effect on ETA, stimulation of other virulence factors could cause increased virulence of this organism in space flight. Similar increased virulence in spaceflight has been observed for other bacteria. This is important because astronauts may be more susceptible to opportunistic pathogens including P. aeruginosa.

  2. [Characterization of the Lipopolysaccharides of Pseudomonas chlororaphis].

    PubMed

    Varbanets, L D; Zdorovenko, E L; Kiprianova, E A; Avdeeva, L V; Brovarskaya, O S; Rybalko, S L

    2015-01-01

    Lipopolysaccharides (LPS) from two strains ot Pseudomonas chlororaphis subsp. aureofaciens,UCM B-111 and UCM B-306, were isolated and characterized. The LPS preparations exhibited low toxicity, high pyrogenicity and high antiviral activity. Mild acid hydrolysis was used to obtain the O-specific polysaccharides. Their structures were established by monosaccharide analysis and determination of absolute configurations, as well as by 1D and 2D NMR spectroscopy. The O-polysaccharides were shown to contain the linear tri- or tetrasaccharide repeating units. Both O-polysaccharides were structurally heterogeneous: P. chlororaphis subsp. aureofaciens UCM B-111--> 4)-αD-GalpNAc6Ac-(1 --> 3)-β-D-QuipNAc-(1 --> 6)-αD-GlcpNAc-(l --> βD-GlcpNAc-(l --> 3)] GalNAc -60%; degree of the non-stoichiometric 6-O-acetylation of GalNAc -60%; P. chlorophis subsp. aureofaciens UCM B-306 --> 3)-α-D-Rhap-(1 --> 4)-α-D-GalpNAcAN-(1 --> 3)-αD-QuipNAc4NAc-(1 -->, where GalNAcAN is 2-acetamido-2-deoxy-D-galacturonamide, the degree of non-stoichiometric amidation of the GalNAcA residue -60%.

  3. Lactobacillus apinorum sp. nov., Lactobacillus mellifer sp. nov., Lactobacillus mellis sp. nov., Lactobacillus melliventris sp. nov., Lactobacillus kimbladii sp. nov., Lactobacillus helsingborgensis sp. nov. and Lactobacillus kullabergensis sp. nov., isolated from the honey stomach of the honeybee Apis mellifera

    PubMed Central

    Alsterfjord, Magnus; Nilson, Bo; Butler, Èile; Vásquez, Alejandra

    2014-01-01

    We previously discovered a symbiotic lactic acid bacterial (LAB) microbiota in the honey stomach of the honeybee Apis mellifera. The microbiota was composed of several phylotypes of Bifidobacterium and Lactobacillus. 16S rRNA gene sequence analyses and phenotypic and genetic characteristics revealed that the phylotypes isolated represent seven novel species. One grouped with Lactobacillus kunkeei and the others belong to the Lactobacillus buchneri and Lactobacillus delbrueckiisubgroups of Lactobacillus. We propose the names Lactobacillus apinorum sp. nov., Lactobacillus mellifer sp. nov., Lactobacillus mellis sp. nov., Lactobacillus melliventris sp. nov., Lactobacillus kimbladii sp. nov., Lactobacillus helsingborgensis sp. nov. and Lactobacillus kullabergensis sp. nov. for these novel species, with the respective type strains being Fhon13NT ( = DSM 26257T = CCUG 63287T), Bin4NT ( = DSM 26254T = CCUG 63291T), Hon2NT ( = DSM 26255T = CCUG 63289T), Hma8NT ( = DSM 26256T = CCUG 63629T), Hma2NT ( = DSM 26263T = CCUG 63633T), Bma5NT ( = DSM 26265T = CCUG 63301T) and Biut2NT ( = DSM 26262T = CCUG 63631T). PMID:24944337

  4. Role of the Pseudomonas quinolone signal (PQS) in sensitising Pseudomonas aeruginosa to UVA radiation.

    PubMed

    Pezzoni, Magdalena; Meichtry, Martín; Pizarro, Ramón A; Costa, Cristina S

    2015-01-01

    One of the main stress factors that bacteria face in the environment is solar ultraviolet-A (UVA) radiation, which leads to lethal effects through oxidative damage. The aim of this work was to investigate the role of 2-heptyl-3-hydroxi-4-quinolone (the Pseudomonas quinolone signal or PQS) in the response of Pseudomonas aeruginosa to UVA radiation. PQS is an intercellular quorum sensing signal associated to membrane vesicles which, among other functions, regulates genes related to iron acquisition, forms stable complexes with iron and participates in oxidative phenomena. UVA exposure of the wild-type PAO1 strain and a pqsA mutant unable to produce PQS revealed a sensitising role for this signal. Research into the mechanism involved in this phenomenon revealed that catalase, an essential factor in the UVA defence, is not related to PQS-mediated UVA sensitivity. Absorption of UVA by PQS produced its own photo-degradation, oxidation of the probe 2',7'- dichlorodihydrofluorescein and generation of singlet oxygen and superoxide anion, suggesting that this signal could be acting as an endogenous photosensitiser. The results presented in this study could explain the high sensitivity to UVA of P. aeruginosa when compared to enteric bacteria.

  5. Dueling quorum sensing systems in Pseudomonas aeruginosa control the production of the Pseudomonas quinolone signal (PQS).

    PubMed

    McGrath, Stephen; Wade, Dana S; Pesci, Everett C

    2004-01-15

    The opportunistic human pathogen Pseudomonas aeruginosa regulates the production of numerous virulence factors via the action of two separate but coordinated quorum sensing systems, las and rhl. These systems control the transcription of genes in response to population density through the intercellular signals N-(3-oxododecanoyl)-L-homoserine lactone (3-oxo-C(12)-HSL) and N-(butanoyl)-L-homoserine lactone (C(4)-HSL). A third P. aeruginosa signal, 2-heptyl-3-hydroxy-4-quinolone [Pseudomonas quinolone signal (PQS)], also plays a significant role in the transcription of multiple P. aeruginosa virulence genes. PQS is intertwined in the P. aeruginosa quorum sensing hierarchy with its production and bioactivity requiring the las and rhl quorum sensing systems, respectively. This report presents a preliminary transcriptional analysis of pqsA, the first gene of the recently discovered PQS biosynthetic gene cluster. We show that pqsA transcription required pqsR, a transcriptional activator protein encoded within the PQS biosynthetic gene cluster. It was also found that the transcription of pqsA and subsequent production of PQS was induced by the las quorum sensing system and repressed by the rhl quorum sensing system. In addition, PQS production was dependent on the ratio of 3-oxo-C(12)-HSL to C(4)-HSL, suggesting a regulatory balance between quorum sensing systems. These data are an important early step toward understanding the regulation of PQS synthesis and the role of PQS in P. aeruginosa intercellular signaling.

  6. The evolutionary stability of cytochrome c-551 in Pseudomonas aeruginosa and Pseudomonas fluorescens biotype C

    PubMed Central

    Ambler, R. P.

    1974-01-01

    Cytochrome c-551 was prepared from nine different strains of Pseudomonas aeruginosa and six of Pseudomonas fluorescens biotype C, and their amino acid sequences were compared with the sequences previously determined for the cytochromes of type strains of each species. The standard of sequence examination was such that all single amino acid substitutions, delections or insertions ought to have been detected. Balanced double changes in sites in the same part of the sequence might have escaped detection. The standard of some of the quantitative amino acid analyses was not as high as would be required for the investigation of completely unknown sequences. Eight of the Ps. aeruginosa sequences could not be distinguished from the type sequence, whereas the ninth had a single amino acid substitution. The sequences from Ps. fluorescens biotype C were more varied, differing in from zero to four substitutions from the type sequence, with the most diverse sequences differing in seven positions. The results for Ps. aeruginosa are interpreted as evidence that neutral mutations are not responsible for much molecular evolution. The superficially paradoxical differences in the results for the two species are discussed. PMID:4362497

  7. COMPARATIVE TAXONOMY OF CRYSTALLOGENIC STRAINS OF PSEUDOMONAS AERUGINOSA AND PSEUDOMONAS CHLORORAPHIS

    PubMed Central

    Haynes, William C.; Rhodes, Lenora J.

    1962-01-01

    Haynes, William C. (Northern Utilization Research and Development Division, Peoria, Ill.) and Lenora J. Rhodes. Comparative taxonomy of crystallogenic strains of Pseudomonas aeruginosa and Pseudomonas chlororaphis. J. Bacteriol. 84:1080–1084. 1962.—Only 11 of 39 strains received in the Agricultural Research Service Culture Collection under the designation Pseudonomas chlororaphis proved to be authentic; 28 were typical, pyocyanogenic strains of P. aeruginosa. The reason for this disproportionately high rate of misidentification apparently arises from an erroneous belief that the ability to produce green and yellow crystals of chlororaphin and oxychlororaphin is confined to P. chlororaphis. The ability of many strains of P. aeruginosa to do likewise is not well known. Inasmuch as the characteristic is not unique to P. chlororaphis, other criteria are required to distinguish crystallogenic strains of these species. After a taxonomic comparison of 18 strains of P. chlororaphis and 47 crystallogenic strains of P. aeruginosa, it was determined that there are three main distinctions: (i) P. aeruginosa grows well at 42 C but fails to grow upon serial transfer at 5 C, whereas P. chlororaphis fails to grow at 42 C, but grows well at 5 C: (ii) most strains of P. aeruginosa produce pyocyanin, whereas P. chlororaphis strains do not; (iii) P. aeruginosa cells possess only one or two polar flagella, whereas P. chlororaphis usually has at least four, sometimes as many as eight, polar flagella. PMID:13963593

  8. SP-100 control system modeling

    NASA Technical Reports Server (NTRS)

    Meyer, R. A.; Halfen, F. J.; Alley, A. D.

    1987-01-01

    SP-100 Control Systems modeling was done using a thermal hydraulic transient analysis model called ARIES-S. The ARIES-S Computer Simulation provides a basis for design, integration and analysis of the reactor including the control and protection systems. It is a modular digital computer simulation written in FORTRAN that operates interactively in real time on a VAX minicomputer.

  9. Argonne's SpEC Module

    ScienceCinema

    Harper, Jason

    2016-07-12

    Jason Harper, an electrical engineer in Argonne National Laboratory's EV-Smart Grid Interoperability Center, discusses his SpEC Module invention that will enable fast charging of electric vehicles in under 15 minutes. The module has been licensed to BTCPower.

  10. Pantoea vagans sp. nov., Pantoea eucalypti sp. nov., Pantoea deleyi sp. nov. and Pantoea anthophila sp. nov.

    PubMed

    Brady, Carrie L; Venter, Stephanus N; Cleenwerck, Ilse; Engelbeen, Katrien; Vancanneyt, Marc; Swings, Jean; Coutinho, Teresa A

    2009-09-01

    Bacteria isolated from eucalyptus leaves and shoots showing symptoms of blight and die-back collected in Uganda, Uruguay and Argentina and from maize displaying brown stalk rot symptoms in South Africa were tentatively placed in the genus Pantoea on the basis of phenotypic and biochemical tests. These isolates, together with two strains (LMG 2558 and LMG 2560) previously assigned to Pantoea agglomerans based on protein electrophoregrams but later excluded from this species, were further investigated using molecular techniques. 16S rRNA gene sequencing and multilocus sequence analyses (MLSA) revealed that the strains were phylogenetically closely related to Pantoea agglomerans, Pantoea stewartii and Pantoea ananatis. MLSA and amplified fragment length polymorphism analysis placed the strains into four separate clusters, not containing any of the type strains of species of the genus Pantoea. DNA-DNA hybridization confirmed the classification of the isolates into four novel species, for which the names Pantoea vagans sp. nov. (type strain R-21566T=LMG 24199T=BCC 105T=BD 765T), Pantoea eucalypti sp. nov. (type strain R-25678T=LMG 24197T=BCC 076T=BD 769T), Pantoea deleyi sp. nov. (type strain R-31523T=LMG 24200T=BCC 109T=BD 767T) and Pantoea anthophila sp. nov. (type strain LMG 2558T=BD 871T=NCPPB 1682T) are proposed.

  11. Argonne's SpEC Module

    SciTech Connect

    Harper, Jason

    2014-05-05

    Jason Harper, an electrical engineer in Argonne National Laboratory's EV-Smart Grid Interoperability Center, discusses his SpEC Module invention that will enable fast charging of electric vehicles in under 15 minutes. The module has been licensed to BTCPower.

  12. The role of Sp1 and Sp3 in the constitutive DPYD gene expression.

    PubMed

    Zhang, Xue; Li, Lin; Fourie, Jeanne; Davie, James R; Guarcello, Vincenzo; Diasio, Robert B

    2006-05-01

    Dihydropyrimidine dehydrogenase (DPD), the initial and rate-limiting enzyme in the 5-fluorouracil (5-FU) catabolic pathway, has been implicated as one of the factors determining the efficacy and toxicity of the anticancer agent 5-FU. Studies have attributed variation in DPD activity partially to alterations at the transcriptional level of DPYD gene. We investigated the transcription factors implicated in the constitutive expression of DPYD by utilizing a 174-bp fragment of the DPYD promoter region in which three consensus Sp protein binding sites (SpA, SpB and SpC) were predicted. The binding of Sp1 and Sp3 transcription factors to this region was detected by electrophoretic mobility shift and chromatin immunoprecipitation assays. By ectopically expressing human Sp1 and Sp3 in Sp-deficient Drosophila S2 cells, we demonstrated that Sp1 is a strong activator, while Sp3 by its own is a weak activator of the DPYD promoter. Moreover, Sp3 may serve as a competitor of Sp1, thus decreasing the Sp1 induced promoter activity. SpA, SpB and SpC sites are all Sp1 inducible. In the full activation of the DPYD promoter in human cell lines, the SpB site is essential; the SpC site works cooperatively with SpB, while SpA has minor promoter activity. These studies provide further insight into the molecular mechanisms underlying the heterogeneity of DPD activity, and may facilitate the efficacy and safety of 5-FU-based chemotherapy.

  13. Bioaugmentation of Mesorhizobium cicer, Pseudomonas spp. and Piriformospora indica for Sustainable Chickpea Production.

    PubMed

    Mansotra, Pallavi; Sharma, Poonam; Sharma, Sunita

    2015-07-01

    Chickpea establishes symbiotic association with Mesorhizobium to fulfill its nitrogen (N) requirement. Integrating chickpea rhizosphere with potential native mesorhizobia and other plant growth promoting microorganisms can contribute multiple benefits to plants. The present investigation was undertaken to study interactions among Piriformospora indica (PI) with potential plant growth promoting rhizobacteria (PGPR) viz. Pseudomonas argentinensis (LPGPR1), Pseudomonas sp. (LPGPR2) along with national check Pseudomons sp. (LK884) and Mesorhizobium cicer (LGR33, MR) to examine the synergistic effect of consortium for improving growth, symbiotic efficiency, nutrient acquisition and yield in two chickpea (Cicer arietinum L.) varieties viz. desi PBG1 and kabuli BG1053. In-vitro, seed germination with consortium MR + PI + LPGPR1 was the best compatible treatment followed by MR + PI + LK884 and MR + PI + LPGPR2. Significant improvement in the growth, symbiotic parameters and grain yield was observed with MR + PI + LPGPR1 and MR + PI + LK884 treatments. Significantly high chlorophyll and leghaemoglobin content was recorded with MR + PI + LPGPR1 (1.57 and 1.64 mg g(-1) fresh weight of leaves and 5.19 and 4.39 mg/g(-1) fresh weight of nodules) in desi PBG1 and kabuli BG1053 chickpea varieties, respectively. At 90 DAS, MR + PI + LPGPR1 treatment significantly improved nodule dry weight (ranged between 84.0 and 141.7 mg plant(-1)) as compared to MR alone treatment (ranged between 62.3 and 123.3 mg plant(-1)). Data revealed significant increase in total nitrogen (N) and phosphorus (P) content of shoot with MR + PI + LPGPR1 by 1.2 and 1.5 fold, respectively over MR alone treatment. On the basis of overall mean, MR + PI + LPGPR1 significantly improved the yield by 8.2 % over Mesorhizobium alone application. It seems from foregoing study that tripartite combination of different micro-organisms can be

  14. Diversity of small RNAs expressed in Pseudomonas species.

    PubMed

    Gómez-Lozano, María; Marvig, Rasmus L; Molina-Santiago, Carlos; Tribelli, Paula M; Ramos, Juan-Luis; Molin, Søren

    2015-04-01

    RNA sequencing (RNA-seq) has revealed several hundreds of previously undetected small RNAs (sRNAs) in all bacterial species investigated, including strains of Pseudomonas aeruginosa, Pseudomonas putida and Pseudomonas syringae. Nonetheless, only little is known about the extent of conservation of expressed sRNAs across strains and species. In this study, we have used RNA-seq to identify sRNAs in P. putida DOT-T1E and Pseudomonas extremaustralis 14-3b. This is the first strain of P. extremaustralis and the second strain of P. putida to have their transcriptomes analysed for sRNAs, and we identify the presence of around 150 novel sRNAs in each strain. Furthermore, we provide a comparison based on sequence conservation of all the sRNAs detected by RNA-seq in the Pseudomonas species investigated so far. Our results show that the extent of sRNA conservation across different species is very limited. In addition, when comparing the sRNAs expressed in different strains of the same species, we observe that numerous sRNAs exhibit a strain-specific expression pattern. These results support the idea that the evolution of most bacterial sRNAs is rapid, which limits the extent of both interspecies and intraspecies conservation.

  15. Marine Sponge-Derived Streptomyces sp. SBT343 Extract Inhibits Staphylococcal Biofilm Formation

    PubMed Central

    Balasubramanian, Srikkanth; Othman, Eman M.; Kampik, Daniel; Stopper, Helga; Hentschel, Ute; Ziebuhr, Wilma; Oelschlaeger, Tobias A.; Abdelmohsen, Usama R.

    2017-01-01

    Staphylococcus epidermidis and Staphylococcus aureus are opportunistic pathogens that cause nosocomial and chronic biofilm-associated infections. Indwelling medical devices and contact lenses are ideal ecological niches for formation of staphylococcal biofilms. Bacteria within biofilms are known to display reduced susceptibilities to antimicrobials and are protected from the host immune system. High rates of acquired antibiotic resistances in staphylococci and other biofilm-forming bacteria further hamper treatment options and highlight the need for new anti-biofilm strategies. Here, we aimed to evaluate the potential of marine sponge-derived actinomycetes in inhibiting biofilm formation of several strains of S. epidermidis, S. aureus, and Pseudomonas aeruginosa. Results from in vitro biofilm-formation assays, as well as scanning electron and confocal microscopy, revealed that an organic extract derived from the marine sponge-associated bacterium Streptomyces sp. SBT343 significantly inhibited staphylococcal biofilm formation on polystyrene, glass and contact lens surfaces, without affecting bacterial growth. The extract also displayed similar antagonistic effects towards the biofilm formation of other S. epidermidis and S. aureus strains tested but had no inhibitory effects towards Pseudomonas biofilms. Interestingly the extract, at lower effective concentrations, did not exhibit cytotoxic effects on mouse fibroblast, macrophage and human corneal epithelial cell lines. Chemical analysis by High Resolution Fourier Transform Mass Spectrometry (HRMS) of the Streptomyces sp. SBT343 extract proportion revealed its chemical richness and complexity. Preliminary physico-chemical characterization of the extract highlighted the heat-stable and non-proteinaceous nature of the active component(s). The combined data suggest that the Streptomyces sp. SBT343 extract selectively inhibits staphylococcal biofilm formation without interfering with bacterial cell viability. Due to

  16. Marine Sponge-Derived Streptomyces sp. SBT343 Extract Inhibits Staphylococcal Biofilm Formation.

    PubMed

    Balasubramanian, Srikkanth; Othman, Eman M; Kampik, Daniel; Stopper, Helga; Hentschel, Ute; Ziebuhr, Wilma; Oelschlaeger, Tobias A; Abdelmohsen, Usama R

    2017-01-01

    Staphylococcus epidermidis and Staphylococcus aureus are opportunistic pathogens that cause nosocomial and chronic biofilm-associated infections. Indwelling medical devices and contact lenses are ideal ecological niches for formation of staphylococcal biofilms. Bacteria within biofilms are known to display reduced susceptibilities to antimicrobials and are protected from the host immune system. High rates of acquired antibiotic resistances in staphylococci and other biofilm-forming bacteria further hamper treatment options and highlight the need for new anti-biofilm strategies. Here, we aimed to evaluate the potential of marine sponge-derived actinomycetes in inhibiting biofilm formation of several strains of S. epidermidis, S. aureus, and Pseudomonas aeruginosa. Results from in vitro biofilm-formation assays, as well as scanning electron and confocal microscopy, revealed that an organic extract derived from the marine sponge-associated bacterium Streptomyces sp. SBT343 significantly inhibited staphylococcal biofilm formation on polystyrene, glass and contact lens surfaces, without affecting bacterial growth. The extract also displayed similar antagonistic effects towards the biofilm formation of other S. epidermidis and S. aureus strains tested but had no inhibitory effects towards Pseudomonas biofilms. Interestingly the extract, at lower effective concentrations, did not exhibit cytotoxic effects on mouse fibroblast, macrophage and human corneal epithelial cell lines. Chemical analysis by High Resolution Fourier Transform Mass Spectrometry (HRMS) of the Streptomyces sp. SBT343 extract proportion revealed its chemical richness and complexity. Preliminary physico-chemical characterization of the extract highlighted the heat-stable and non-proteinaceous nature of the active component(s). The combined data suggest that the Streptomyces sp. SBT343 extract selectively inhibits staphylococcal biofilm formation without interfering with bacterial cell viability. Due to

  17. Pseudomonas fluorescens' view of the periodic table.

    PubMed

    Workentine, Matthew L; Harrison, Joe J; Stenroos, Pernilla U; Ceri, Howard; Turner, Raymond J

    2008-01-01

    Growth in a biofilm modulates microbial metal susceptibility, sometimes increasing the ability of microorganisms to withstand toxic metal species by several orders of magnitude. In this study, a high-throughput metal toxicity screen was initiated with the aim of correlating biological toxicity data in planktonic and biofilm cells to the physiochemical properties of metal ions. To this end, Pseudomonas fluorescens ATCC 13525 was grown in the Calgary Biofilm Device (CBD) and biofilms and planktonic cells of this microorganism were exposed to gradient arrays of different metal ions. These arrays included 44 different metals with representative compounds that spanned every group of the periodic table (except for the halogens and noble gases). The minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and minimum biofilm eradication concentration (MBEC) values were obtained after exposing the biofilms to metal ions for 4 h. Using these values, metal ion toxicity was correlated to the following ion-specific physicochemical parameters: standard reduction-oxidation potential, electronegativity, the solubility product of the corresponding metal-sulfide complex, the Pearson softness index, electron density and the covalent index. When the ions were grouped according to outer shell electron structure, we found that heavy metal ions gave the strongest correlations to these parameters and were more toxic on average than the other classes of the ions. Correlations were different for biofilms than for planktonic cells, indicating that chemical mechanisms of metal ion toxicity differ between the two modes of growth. We suggest that biofilms can specifically counter the toxic effects of certain physicochemical parameters, which may contribute to the increased ability of biofilms to withstand metal toxicity.

  18. The Regulatory Network of Pseudomonas aeruginosa

    PubMed Central

    2011-01-01

    Background Pseudomonas aeruginosa is an important bacterial model due to its metabolic and pathogenic abilities, which allow it to interact and colonize a wide range of hosts, including plants and animals. In this work we compile and analyze the structure and organization of an experimentally supported regulatory network in this bacterium. Results The regulatory network consists of 690 genes and 1020 regulatory interactions between their products (12% of total genes: 54% sigma and 16% of transcription factors). This complex interplay makes the third largest regulatory network of those reported in bacteria. The entire network is enriched for activating interactions and, peculiarly, self-activation seems to occur more prominent for transcription factors (TFs), which contrasts with other biological networks where self-repression is dominant. The network contains a giant component of 650 genes organized into 11 hierarchies, encompassing important biological processes, such as, biofilms formation, production of exopolysaccharide alginate and several virulence factors, and of the so-called quorum sensing regulons. Conclusions The study of gene regulation in P. aeruginosa is biased towards pathogenesis and virulence processes, all of which are interconnected. The network shows power-law distribution -input degree -, and we identified the top ten global regulators, six two-element cycles, the longest paths have ten steps, six biological modules and the main motifs containing three and four elements. We think this work can provide insights for the design of further studies to cover the many gaps in knowledge of this important bacterial model, and for the design of systems strategies to combat this bacterium. PMID:22587778

  19. A Genomic Redefinition of Pseudomonas avellanae species

    PubMed Central

    Scortichini, Marco; Marcelletti, Simone; Ferrante, Patrizia; Firrao, Giuseppe

    2013-01-01

    The circumscription of bacterial species is a complex task. So far, DNA-DNA hybridization (DDH), 16S rRNA gene sequencing, and multiocus sequence typing analysis (MLSA) are currently the preferred techniques for their genetic determination. However, the average nucleotide identity (ANI) analysis of conserved and shared genes between two bacterial strains based on the pair-wise genome comparisons, with support of the tetranucleotide frequency correlation coefficients (TETRA) value, has recently been proposed as a reliable substitute for DDH. The species demarcation boundary has been set to a value of 95-96% of the ANI identity, with further confirmation through the assessment of the corresponding TETRA value. In this study, we performed a genome-wide MLSA of 14 phytopathogenic pseudomonads genomes, and assessed the ANI and TETRA values of 27 genomes, representing seven out of the nine genomospecies of Pseudomonas spp. sensu Gardan et alii, and their phylogenetic relationships using maximum likelihood and Bayesian approaches. The results demonstrate the existence of a well demarcated genomic cluster that includes strains classified as P. avellanae, P. syringae pv. theae, P. s. pv. actinidiae and one P. s. pv. morsprunorum strain all belonging to the single species P. avellanae. In addition, when compared with P. avellanae, five strains of P. s. pv. tomato, including the model strain DC3000, and one P. s. pv. lachrymans strain, appear as very closely related to P. avellanae, with ANI values of nearly 96% as confirmed by the TETRA analysis. Conversely, one representative strain, previously classified as P. avellanae and isolated in central Italy, is a genuine member of the P. syringae species complex and can be defined as P. s. pv. avellanae. Currently. The core and pan genomes of P. avellanae species consist of 3,995 and 5,410 putative protein-coding genes, respectively. PMID:24086635

  20. Ambroxol interferes with Pseudomonas aeruginosa quorum sensing.

    PubMed

    Lu, Qi; Yu, Jialin; Yang, Xiqiang; Wang, Jiarong; Wang, Lijia; Lin, Yayin; Lin, Lihua

    2010-09-01

    The mucolytic agent ambroxol has been reported to interfere with the formation of Pseudomonas aeruginosa-derived biofilms in addition to reducing alginate production by undefined mechanisms. Since quorum sensing is a key regulator of virulence and biofilm formation, we examined the effects of ambroxol on P. aeruginosa PAO1 wild-type bacterial clearance rates, adhesion profiles and biofilm formation compared with the quorum sensing-deficient, double-mutant strains DeltalasR DeltarhlR and DeltalasI DeltarhlI. Data presented in this report demonstrated that ambroxol treatment reduced survival rates of the double-mutant strains compared with the wild-type strain in a dose-dependent manner even though the double-mutants had increased adhesion in the presence of ambroxol compared with the wild-type strain. The PAO1 wild-type strain produced a significantly thicker biofilm (21.64+/-0.57 microm) compared with the biofilms produced by the DeltalasR DeltarhlR (7.36+/-0.2 microm) and DeltalasI DeltarhlI (6.62+/-0.31 microm) isolates. Ambroxol treatment reduced biofilm thickness, increased areal porosity, and decreased the average diffusion distance and textual entropy of wild-type and double-mutant strains. However, compared with the double-mutant strains, the changes observed for the wild-type strain were more clearly defined. Finally, ambroxol exhibited significant antagonistic quorum-sensing properties, suggesting that it could be adapted for use clinically in the treatment of cystic fibrosis and to reduce biofilm formation and in the colonisation of indwelling devices.

  1. Cryptic transposable phages of Pseudomonas aeruginosa

    SciTech Connect

    Krylov, V.N.; Mit`kina, L.N.; Pleteneva, E.A.; Aleshin, V.V.

    1995-11-01

    Frequencies of nucleotide sequences homologous to phage transposons (PT) of two species, D3112 and B3, were assessed in genomes of natural Pseudomonas aeruginosa strains by the dot-blot hybridization method. These strains were incapable of liberating viable phages on a lawn of the PA01 standard indicator strain of P. aeruginosa. It was shown that the homologies detected belong to two groups, high and intermediate, with respect to homology level. Homology patterns were classified as high when they provided signals comparable to those for hybridization in a positive control; patterns were classified as intermediate when the hybridization level was higher than the background level, but lower than in the positive control. Homologous PT sequences were designated as cryptic PT. Intact cryptic PT prophages were shown to exist in genomes of particular natural strains manifesting a higher level of hybridization. However, the growth of these phages was limited by the restriction system of strain PA01. It is possible to isolate strains maintaining the growth of some cryptic PT. These strains differed from P. aeruginosa with respect to the specificity of the restriction and modification system. Nevertheless, in most cases, the attempt to identify a novel host capable of maintaining growth of a cryptic PT failed. Natural strains often carry cryptic PT related to both known PT species, D3112 and B3. The frequency of cryptic PT is extremely high, reaching 30% in strains with a high level of homology only and up to 50% in all strains exhibiting homology. This high PT frequency is assumed to be associated with the considerable variation of P. aeruginosa. 15 refs., 1 fig., 2 tabs.

  2. Regulation of Glucose Metabolism in Pseudomonas

    PubMed Central

    Daddaoua, Abdelali; Krell, Tino; Ramos, Juan-Luis

    2009-01-01

    In Pseudomonas putida, genes for the glucose phosphorylative pathway and the Entner-Doudoroff pathway are organized in two operons; one made up of the zwf, pgl, and eda genes and another consisting of the edd, glk, gltR2, and gltS genes. Divergently with respect to the edd gene is the gap-1 gene. Expression from Pzwf, Pedd, and Pgap is modulated by HexR in response to the availability of glucose in the medium. To study the regulatory process in greater detail we purified HexR and showed that it is a monomer in solution. Electrophoretic mobility shift assays and isothermal titration calorimetry assays were done showing that HexR recognizes the Pedd, Pzwf, and Pgap-1 promoters with affinity in the nanomolar range. DNA footprinting assays identified the binding site between +30 and +1 at Pzwf, between +16 and +41 at Pedd, and between −6 and +18 at Pgap-1. Based on DNA sequence alignment of the target sites and isothermal titration calorimetry data, two monomers of HexR bind to a pseudopalindrome with a consensus sequence of 5′-TTGTN7–8ACAA-3′. Binding of the Entner-Doudoroff pathway intermediate 2-keto-3-deoxy-6-phosphogluconate to HexR released the repressor from its target operators, whereas other chemicals such as glucose, glucose 6-phosphate, and 6-phosphogluconate did not induce complex dissociation. The phosphorylated effector is likely to be recognized by a sugar isomerase domain located at the C-terminal end of HexR, whereas the helix-turn-helix DNA binding domain of HexR exhibits high similarity to proteins of the RpiR family of regulators. PMID:19506074

  3. Social cheating in Pseudomonas aeruginosa quorum sensing.

    PubMed

    Sandoz, Kelsi M; Mitzimberg, Shelby M; Schuster, Martin

    2007-10-02

    In a process termed quorum sensing, bacteria use diffusible chemical signals to coordinate cell density-dependent gene expression. In the human pathogen Pseudomonas aeruginosa, quorum sensing controls hundreds of genes, many of which encode extracellular virulence factors. Quorum sensing is required for P. aeruginosa virulence in animal models. Curiously, quorum sensing-deficient variants, most of which carry a mutation in the gene encoding the central quorum sensing regulator lasR, are frequently isolated from acute and chronic infections. The mechanism for their emergence is not known. Here we provide experimental evidence suggesting that these lasR mutants are social cheaters that cease production of quorum-controlled factors and take advantage of their production by the group. We detected an emerging subpopulation of lasR mutants after approximately 100 generations of in vitro evolution of the P. aeruginosa wild-type strain under culture conditions that require quorum sensing for growth. Under such conditions, quorum sensing appears to impose a metabolic burden on the proliferating bacterial cell, because quorum-controlled genes not normally induced until cessation of growth were highly expressed early in growth, and a defined lasR mutant showed a growth advantage when cocultured with the parent strain. The emergence of quorum-sensing-deficient variants in certain environments is therefore an indicator of high quorum sensing activity of the bacterial population as a whole. It does not necessarily indicate that quorum sensing is insignificant, as has previously been suggested. Thus, novel antivirulence strategies aimed at disrupting bacterial communication may be particularly effective in such clinical settings.

  4. Risk assessment of Pseudomonas aeruginosa in water.

    PubMed

    Mena, Kristina D; Gerba, Charles P

    2009-01-01

    from ingesting P. aeruginosa in drinking water is low. The risk is slightly higher if the subject is taking an antibiotic resisted by P. aeruginosa. The fact that individuals on ampicillin are more susceptible to Pseudomonas gastrointestinal infection probably results from suppression of normal intestinal flora, which would allow Pseudomonas to colonize. The process of estimating risk was significantly constrained because of the absence of specific (quantitative) occurrence data for Pseudomonas. Sensitivity analysis shows that the greatest source of variability/uncertainty in the risk assessment is from the density distribution in the exposure rather than the dose-response or water consumption distributions. In summary, two routes appear to carry the greatest health risks from contacting water contaminated with P. aeruginosa (1) skin exposure in hot tubs and (2) lung exposure from inhaling aerosols.

  5. Bacteriophage SP6 encodes a second tailspike protein that recognizes Salmonella enterica serogroups C2 and C3.

    PubMed

    Gebhart, Dana; Williams, Steven R; Scholl, Dean

    2017-03-10

    SP6 is a salmonella phage closely related to coliphage K1-5. K1-5 is notable in that it encodes two polysaccharide-degrading tailspike proteins, an endosialidase that allows it to infect E. coli K1, and a lyase that enables it to infect K5 strains. SP6 is similar to K1-5 except that it encodes a P22-like endorhamnosidase tailspike, gp46, allowing it to infect group B Salmonella. We show here that SP6 can also infect Salmonella serogroups C2 and C3 and that a mutation in a putative second tailspike, gp47, eliminates this specificity. Gene 47 was fused to the coding region of the N-terminal portion of the Pseudomonas aeruginosa R2 pyocin tail fiber and expressed in trans such that the fusion protein becomes incorporated into pyocin particles. These pyocins, termed AvR2-SP47, killed serogroups C2 and C3Salmonella. We conclude that SP6 encodes two tail proteins providing it a broad host range among Salmonella enterica.

  6. Biological manganese oxidation by Pseudomonas putida in trickling filters.

    PubMed

    McKee, Kyle P; Vance, Cherish C; Karthikeyan, Raghupathy

    2016-01-01

    Biological oxidation has been researched as a viable alternative for treating waters with high manganese (Mn) concentrations, typically found in mine drainage or in some geological formations. In this study, laboratory-scale trickling filters were constructed to compare the Mn removal efficiency between filters inoculated with the Mn oxidizing bacteria, Pseudomonas putida, and filters without inoculation. Manganese oxidation and removal was found to be significantly greater in trickling filters with Pseudomonas putida after startup times of only 48 h. Mn oxidation in Pseudomonas putida inoculated trickling filters was up to 75% greater than non-inoculated filters. One-dimensional advective-dispersive models were formulated to describe the transport of Mn in trickling filter porous media. Based on the experimental transport parameters obtained, the model predicted that a filter depth of only 16 cm is needed to reduce influent concentration of 10 mg L(-1) to 0.05 mg L(-1).

  7. Biotransformation of Tributyltin chloride by Pseudomonas stutzeri strain DN2

    PubMed Central

    Khanolkar, Dnyanada S.; Naik, Milind Mohan; Dubey, Santosh Kumar

    2014-01-01

    A bacterial isolate capable of utilizing tributyltin chloride (TBTCl) as sole carbon source was isolated from estuarine sediments of west coast of India and identified as Pseudomonas stutzeri based on biochemical tests and Fatty acid methyl ester (FAME) analysis. This isolate was designated as strain DN2. Although this bacterial isolate could resist up to 3 mM TBTCl level, it showed maximum growth at 2 mM TBTCl in mineral salt medium (MSM). Pseudomonas stutzeri DN2 exposed to 2 mM TBTCl revealed significant alteration in cell morphology as elongation and shrinkage in cell size along with roughness of cell surface. FTIR and NMR analysis of TBTCl degradation product extracted using chloroform and purified using column chromatography clearly revealed biotransformation of TBTCl into Dibutyltin dichloride (DBTCl2) through debutylation process. Therefore, Pseudomonas stutzeri strain DN2 may be used as a potential bacterial strain for bioremediation of TBTCl contaminated aquatic environmental sites. PMID:25763027

  8. Subtilase SprP exerts pleiotropic effects in Pseudomonas aeruginosa

    PubMed Central

    Pelzer, Alexander; Polen, Tino; Funken, Horst; Rosenau, Frank; Wilhelm, Susanne; Bott, Michael; Jaeger, Karl-Erich

    2014-01-01

    The open reading frame PA1242 in the genome of Pseudomonas aeruginosa PAO1 encodes a putative protease belonging to the peptidase S8 family of subtilases. The respective enzyme termed SprP consists of an N-terminal signal peptide and a so-called S8 domain linked by a domain of unknown function (DUF). Presumably, this DUF domain defines a discrete class of Pseudomonas proteins as homologous domains can be identified almost exclusively in proteins of the genus Pseudomonas. The sprP gene was expressed in Escherichia coli and proteolytic activity was demonstrated. A P. aeruginosa ΔsprP mutant was constructed and its gene expression pattern compared to the wild-type strain by genome microarray analysis revealing altered expression levels of 218 genes. Apparently, SprP is involved in regulation of a variety of different cellular processes in P. aeruginosa including pyoverdine synthesis, denitrification, the formation of cell aggregates, and of biofilms. PMID:24376018

  9. Subtilase SprP exerts pleiotropic effects in Pseudomonas aeruginosa.

    PubMed

    Pelzer, Alexander; Polen, Tino; Funken, Horst; Rosenau, Frank; Wilhelm, Susanne; Bott, Michael; Jaeger, Karl-Erich

    2014-02-01

    The open reading frame PA1242 in the genome of Pseudomonas aeruginosa PAO1 encodes a putative protease belonging to the peptidase S8 family of subtilases. The respective enzyme termed SprP consists of an N-terminal signal peptide and a so-called S8 domain linked by a domain of unknown function (DUF). Presumably, this DUF domain defines a discrete class of Pseudomonas proteins as homologous domains can be identified almost exclusively in proteins of the genus Pseudomonas. The sprP gene was expressed in Escherichia coli and proteolytic activity was demonstrated. A P. aeruginosa ∆sprP mutant was constructed and its gene expression pattern compared to the wild-type strain by genome microarray analysis revealing altered expression levels of 218 genes. Apparently, SprP is involved in regulation of a variety of different cellular processes in P. aeruginosa including pyoverdine synthesis, denitrification, the formation of cell aggregates, and of biofilms.

  10. Diversity and antibiotic resistance in Pseudomonas spp. from drinking water.

    PubMed

    Vaz-Moreira, Ivone; Nunes, Olga C; Manaia, Célia M

    2012-06-01

    Pseudomonas spp. are common inhabitants of aquatic environments, including drinking water. Multi-antibiotic resistance in clinical isolates of P. aeruginosa is widely reported and deeply characterized. However, the information regarding other species and environmental isolates of this genus is scant. This study was designed based on the hypothesis that members of the genus Pseudomonas given their high prevalence, wide distribution in waters and genetic plasticity can be important reservoirs of antibiotic resistance in drinking water. With this aim, the diversity and antibiotic resistance phenotypes of Pseudomonas isolated from different drinking water sources were evaluated. The genotypic diversity analyses were based on six housekeeping genes (16S rRNA, rpoD, rpoB, gyrB, recA and ITS) and on pulsed field gel electrophoresis. Susceptibility to 21 antibiotics of eight classes was tested using the ATB PSE EU (08) and disk diffusion methods. Pseudomonas spp. were isolated from 14 of the 32 sampled sites. A total of 55 non-repetitive isolates were affiliated to twenty species. Although the same species were isolated from different sampling sites, identical genotypes were never observed in distinct types of water (water treatment plant/distribution system, tap water, cup fillers, biofilm, and mineral water). In general, the prevalence of antibiotic resistance was low and often the resistance patterns were related with the species and/or the strain genotype. Resistance to ticarcillin, ticarcillin with clavulanic acid, fosfomycin and cotrimoxazol were the most prevalent (69-84%). No resistance to piperacillin, levofloxacin, ciprofloxacin, tetracycline, gentamicin, tobramycin, amikacin, imipenem or meropenem was observed. This study demonstrates that Pseudomonas spp. are not so widespread in drinking water as commonly assumed. Nevertheless, it suggests that water Pseudomonas can spread acquired antibiotic resistance, preferentially via vertical transmission.

  11. Antioxidant capacity, polyphenol content and iron bioavailability from algae (Ulva sp., Sargassum sp. and Porphyra sp.) in human subjects.

    PubMed

    García-Casal, Maria N; Ramírez, José; Leets, Irene; Pereira, Ana C; Quiroga, Maria F

    2009-01-01

    Marine algae are easily produced and are good sources of Fe. If this Fe is bioavailable, algae consumption could help to combat Fe deficiency and anaemia worldwide. The objective of the present study was to evaluate Fe bioavailability, polyphenol content and antioxidant capacity from three species of marine algae distributed worldwide. A total of eighty-three subjects received maize- or wheat-based meals containing marine algae (Ulva sp., Sargassum sp. and Porphyra sp.) in different proportions (2.5, 5.0 and 7.5 g) added to the water to prepare the dough. All meals administered contained radioactive Fe. Absorption was evaluated calculating radioactive Fe incorporation in subjects' blood. The three species of marine algae were analysed for polyphenol content and reducing power. Algae significantly increased Fe absorption in maize- or wheat-based meals, especially Sargassum sp., due to its high Fe content. Increases in absorption were dose-dependent and higher in wheat- than in maize-based meals. Total polyphenol content was 10.84, 18.43 and 80.39 gallic acid equivalents/g for Ulva sp., Porphyra sp. and Sargassum sp., respectively. The antioxidant capacity was also significantly higher in Sargassum sp. compared with the other two species analysed. Ulva sp., Sargassum sp. and Porphyra sp. are good sources of bioavailable Fe. Sargassum sp. resulted in the highest Fe intake due to its high Fe content, and a bread containing 7.5 g Sargassum sp. covers daily Fe needs. The high polyphenol content found in Sargassum sp. could be partly responsible for the antioxidant power reported here, and apparently did not affect Fe absorption.

  12. IDENTIFICATION OF Pseudomonas spp. AS AMOEBA-RESISTANT MICROORGANISMS IN ISOLATES OF Acanthamoeba

    PubMed Central

    Maschio, Vinicius José; Corção, Gertrudes; Rott, Marilise Brittes

    2015-01-01

    Acanthamoeba is a “Trojan horse” of the microbial world. The aim of this study was to identify the presence of Pseudomonas as an amoeba-resistant microorganism in 12 isolates of Acanthamoeba. All isolates showed the genus Pseudomonas spp. as amoeba-resistant microorganisms. Thus, one can see that the Acanthamoeba isolates studied are hosts of Pseudomonas. PMID:25651331

  13. Genetically enhanced cellulase production in Pseudomonas cellulosa using recombinant DNA technology

    DOEpatents

    Dees, H. Craig

    1999-01-01

    An enhanced strain of Pseudomonas celllulosa was obtained by introducing a recombinant genetic construct comprising a heterologous cellulase gene operably connected to a promoter into ATCC 55702, mutagenizing the transformants by treatment with MNNG, and selecting a high cellulase producing transformant. The transformant, designated Pseudomonas cellulosa ATCC XXXX, exhibits enhanced levels of cellulase production relative to the untransformed Pseudomonas cellulosa strain #142 ATCC 55702.

  14. identification of Pseudomonas spp. as amoeba-resistant microorganisms in isolates of Acanthamoeba.

    PubMed

    José Maschio, Vinicius; Corção, Gertrudes; Rott, Marilise Brittes

    2015-01-01

    Acanthamoeba is a "Trojan horse" of the microbial world. The aim of this study was to identify the presence of Pseudomonas as an amoeba-resistant microorganism in 12 isolates of Acanthamoeba. All isolates showed the genus Pseudomonas spp. as amoeba-resistant microorganisms. Thus, one can see that the Acanthamoeba isolates studied are hosts of Pseudomonas.

  15. Bacillus novalis sp. nov., Bacillus vireti sp. nov., Bacillus soli sp. nov., Bacillus bataviensis sp. nov. and Bacillus drentensis sp. nov., from the Drentse A grasslands.

    PubMed

    Heyrman, Jeroen; Vanparys, Bram; Logan, Niall A; Balcaen, An; Rodríguez-Díaz, Marina; Felske, Andreas; De Vos, Paul

    2004-01-01

    A group of 42 isolates were isolated from the soil of several disused hay fields, in the Drentse A agricultural research area (The Netherlands), that were taken out of production at different times. The group represents hitherto-uncultured Bacillus lineages that have previously been found, by a non-cultural method, to be predominant in soil. The strains were subjected to a polyphasic taxonomic study, including (GTG)5-PCR, 16S rDNA sequence analysis, DNA-DNA hybridizations, DNA base-ratio determination, fatty acid analysis and morphological and biochemical characterization. By comparing the groupings obtained by (GTG)5-PCR and 16S rDNA sequence analysis, six clusters of similar strains could be recognized. A DNA-DNA relatedness study showed that these clusters represented five novel genospecies. Further analysis supported the proposal of five novel species in the genus Bacillus, namely Bacillus novalis sp. nov. (type strain IDA3307T=R-15439T=LMG 21837T=DSM 15603T), Bacillus vireti sp. nov. (type strain IDA3632T=R-15447T=LMG 21834T=DSM 15602T), Bacillus soli sp. nov. (type strain IDA0086T=R-16300T=LMG 21838T=DSM 15604T), Bacillus bataviensis sp. nov. (type strain IDA1115T=R-16315T=LMG 21833T=DSM 15601T) and Bacillus drentensis sp. nov. (type strain IDA1967T=R-16337T=LMG 21831T=DSM 15600T).

  16. Anionic fluoroquinolones as antibacterials against biofilm-producing Pseudomonas aeruginosa.

    PubMed

    Long, Timothy E; Keding, Lexie C; Lewis, Demetria D; Anstead, Michael I; Withers, T Ryan; Yu, Hongwei D

    2016-02-15

    Pseudomonas aeruginosa is a common biofilm-forming bacterial pathogen implicated in diseases of the lungs. The extracellular polymeric substances (EPS) of respiratory Pseudomonas biofilms are largely comprised of anionic molecules such as rhamnolipids and alginate that promote a mucoid phenotype. In this Letter, we examine the ability of negatively-charged fluoroquinolones to transverse the EPS and inhibit the growth of mucoid P. aeruginosa. Anionic fluoroquinolones were further compared with standard antibiotics via a novel microdiffusion assay to evaluate drug penetration through pseudomonal alginate and respiratory mucus from a patient with cystic fibrosis.

  17. Bioactive metabolites from an endophytic Cryptosporiopsis sp. inhabiting Clidemia hirta.

    PubMed

    Zilla, Mahesh K; Qadri, Masroor; Pathania, Anup S; Strobel, Gary A; Nalli, Yedukondalu; Kumar, Sunil; Guru, Santosh K; Bhushan, Shashi; Singh, Sanjay K; Vishwakarma, Ram A; Riyaz-Ul-Hassan, Syed; Ali, Asif

    2013-11-01

    An endophytic Cryptosporiopsis sp. was isolated from Clidemia hirta and analyzed for its secondary metabolites that lead to the isolation of three bioactive molecules. The compounds were purified from the culture broth of the fungus and their structures were determined by spectroscopic methods as (R)-5-hydroxy-2-methylchroman-4-one (1), 1-(2,6-dihydroxyphenyl)pentan-1-one (2) and (Z)-1-(2-(2-butyryl-3-hydroxyphenoxy)-6-hydroxyphenyl)-3-hydroxybut-2-en-1-one (3). Compound 1 exhibited significant cytotoxic activity against the human leukemia cell line, HL-60 with an IC50 of 4 μg/ml. This compound induced G2 arrest of the HL-60 cell cycle significantly. In addition, out of these compounds, 2 and 3 were active against several bacterial pathogens. Compound 2 was active against Bacillus cereus, Escherichia coli and Staphylococcus aureus with IC50 values varying from 18 to 30 μg/ml, and compound 3 displayed activity against Pseudomonas fluorescens with an IC50 value of 6 μg/ml. Compounds 2 and 3 are novel whereas compound 1 was reported earlier but the stereochemistry of its C-2 methyl is established for the first time.

  18. Impaired Pulmonary Defense Against Pseudomonas aeruginosa in VEGF Gene Inactivated Mouse Lung

    PubMed Central

    Breen, Ellen C.; Malloy, Jaret L.; Tang, Kechun; Xia, Feng; Fu, Zhenxing; Hancock, Robert E. W.; Overhage, Joerg; Wagner, Peter D.; Spragg, Roger G.

    2012-01-01

    Repeated bacterial and viral infections are known to contribute to worsening lung function in several respiratory diseases, including asthma, cystic fibrosis and chronic obstructive pulmonary disease (COPD). Previous studies have reported alveolar wall cell apoptosis and parenchymal damage in adult pulmonary VEGF gene ablated mice. We hypothesized that VEGF expressed by type II cells is also necessary to provide an effective host defense against bacteria in part by maintaining surfactant homeostasis. Therefore, Pseudomonas aeruginosa (PAO1) levels were evaluated in mice following lung-targeted VEGF gene inactivation, and alterations in VEGF-dependent type II cell function were evaluated by measuring surfactant homeostasis in mouse lungs and isolated type II cells. In VEGF-deficient lungs increased PAO1 levels and pro-inflammatory cytokines, TNFα and IL-6, were detected 24 hours after bacterial instillation compared to control lungs. In vivo lung-targeted VEGF gene deletion (57% decrease in total pulmonary VEGF) did not alter alveolar surfactant or tissue disaturated phosphatidylcholine (DSPC) levels. However, sphingomyelin content, choline phosphate cytidylyltransferase (CCT) mRNA and SP-D expression were decreased. In isolated type II cells an 80% reduction of VEGF protein resulted in decreases in total phospholipids (PL), DSPC, DSPC synthesis, surfactant associated proteins (SP)-B and -D, and the lipid transporters, ABCA1 and Rab3D. TPA-induced DSPC secretion and apoptosis were elevated in VEGF-deficient type II cells. These results suggest a potential protective role for type II cell-expressed VEGF against bacterial initiated infection. PMID:22718316

  19. Expression of a fully functional cd1 nitrite reductase from Pseudomonas aeruginosa in Pseudomonas stutzeri.

    PubMed

    Arese, Marzia; Zumft, Walter G; Cutruzzolà, Francesca

    2003-01-01

    Nitrite reductases are redox enzymes catalysing the one electron reduction of nitrite to nitrogen monoxide (NO) within the bacterial denitrification process. We have cloned the gene for cd(1) nitrite reductase (Pa-nirS) from Pseudomonas aeruginosa into the NiRS(-) strain MK202 of Pseudomonas stutzeri and expressed the enzyme under denitrifying conditions. In the MK202 strain, denitrification is abolished by the disruption of the endogenous nitrite reductase gene; thus, cells can be grown only in the presence of oxygen. After complementation with Pa-nirS gene, cells supplemented with nitrate can be grown in the absence of oxygen. The presence of nitrite reductase was proven in vivo by the demonstration of NO production, showing that the enzyme was expressed in the active form, containing both heme c and d(1). A purification procedure for the recombinant PaNir has been developed, based on the P. aeruginosa purification protocol; spectroscopic analysis of the purified protein fully confirms the presence of the d(1) heme cofactor. Moreover, the functional characterisation of the recombinant NiR has been carried out by monitoring the production of NO by the purified NiR enzyme in the presence of nitrite by an NO electrode. The full recovery of the denitrification properties in the P. stutzeri MK202 strain by genetic complementation with Pa-NiR underlines the high homology between enzymes of nitrogen oxianion respiration. Our work provides an expression system for cd(1) nitrite reductase and its site-directed mutants in a non-pathogenic strain and is a starting point for the in vivo study of recombinant enzyme variants.

  20. Secretion of Pseudomonas aeruginosa Type III Cytotoxins is Dependent on Pseudomonas Quinolone Signal Concentration

    PubMed Central

    Singh, G.; Wu, B.; Baek, M.S.; Camargo, A.; Nguyen, A.; Slusher, N.A.; Srinivasan, R.; Wiener-Kronish, J.P.; Lynch, S.V.

    2010-01-01

    Pseudomonas aeruginosa is an opportunistic pathogen that can, like other bacterial species, exist in antimicrobial resistant sessile biofilms and as free-swimming, planktonic cells. Specific virulence factors are typically associated with each lifestyle and several two-component response regulators have been shown to reciprocally regulate transition between biofilm-associated chronic, and free-swimming acute infections. Quorum sensing (QS) signal molecules belonging to the las and rhl systems are known to regulate virulence gene expression by P. aeruginosa. However the impact of a recently described family of novel quorum sensing signals produced by the Pseudomonas Quinolone Signal (PQS) biosynthetic pathway, on the transition between these modes of infection is less clear. Using clonal isolates from a patient developing ventilator-associated pneumonia, we demonstrated that clinical observations were mirrored by an in vitro temporal shift in isolate phenotype from a non-secreting, to a Type III cytotoxin secreting (TTSS) phenotype and further, that this phenotypic change was PQS-dependent. While intracellular type III cytotoxin levels were unaffected by PQS concentration, cytotoxin secretion was dependent on this signal molecule. Elevated PQS concentrations were associated with inhibition of cytotoxin secretion coincident with expression of virulence factors such as elastase and pyoverdin. In contrast, low concentrations or the inability to biosynthesize PQS resulted in a reversal of this phenotype. These data suggest that expression of specific P. aeruginosa virulence factors appears to be reciprocally regulated and that an additional level of PQS-dependent posttranslational control, specifically governing type III cytotoxin secretion, exists in this species. PMID:20570614

  1. Survival of rifampin-resistant mutants of Pseudomonas fluorescens and Pseudomonas putida in soil systems.

    PubMed Central

    Compeau, G; Al-Achi, B J; Platsouka, E; Levy, S B

    1988-01-01

    The fate of spontaneous chromosomal rifampin-resistant (Rifr) mutants of Pseudomonas putida and Pseudomonas fluorescens in sterile and live organic soil from which they were isolated was studied. In sterile native-soil assays, a Rifr mutant of P. putida showed no decrease in competitive fitness when compared with the wild-type parent. However, mutants of P. fluorescens were of two general categories. Group 1 showed no difference from the wild type in terms of growth rate, competitive fitness, and membrane protein composition. Group 2 showed a slower growth rate in both minimal and enriched media and an altered membrane protein profile. These mutants also demonstrated decreased competitive fitness compared with the wild-type strain. In live soil, the Rifr P. putida strain persisted throughout the 38-day test period with a decay rate of 0.7 log10 CFU/g of soil per 10 days. A group 1 Rifr P. fluorescens mutant maintained its inoculated titer for 7 to 10 days and then decayed at a rate of 0.2 to 0.4 log10 CFU/g of soil per 10 days. A group 2 Rifr P. fluorescens mutant remained at its titer for 1 to 5 days before decaying at a two- to threefold-faster rate. These findings indicate that rifampin resistance may not be an innocuous mutation in some pseudomonads and that marked strains should be compared with wild-type parents before being used as monitors of parental strain survival. Colonization of sterile soil with either the wild-type or mutant strain precluded normal colonization of the second added strain.(ABSTRACT TRUNCATED AT 250 WORDS) Images PMID:3144244

  2. Evaluation of antimicrobial, cytotoxic, and hemolytic activities from venom of the spider Lasiodora sp.

    PubMed

    Ferreira, Felipe Roberto Borba; da Silva, Pollyanna Michelle; Soares, Tatiana; Gonçalves Machado, Larissa; de Araújo, Larissa Cardoso Corrêa; da Silva, Teresinha Gonçalves; de Mello, Gabriela Souto Vieira; Galdino da Rocha Pitta, Maira; de Melo Rego, Moacyr Jesus Barreto; Pontual, Emmanuel Viana; Zingali, Russolina Benedeta; Napoleão, Thiago Henrique; Paiva, Patrícia Maria Guedes

    2016-11-01

    This study characterized the protein/peptide profile of venom isolated from the spider Lasiodora sp. (Mygalomorphae, Theraphosidae) found in northeastern Brazil and determined its antimicrobial activity, toxicity against human cells, and hemolytic activity. Protein concentration of the Lasiodora sp. venom was 4.53 ± 0.38 mg/mL. SDS-PAGE showed proteins with molecular masses up to 75 kDa, some of which contained disulfide bridges. RP-HPLC analysis separate at least 12 peaks that were identified by mass spectrometry as peptides U1-theraphotoxin-Lp1a (lasiotoxin-1), U1-theraphotoxin-Lp1c (lasiotoxin-3), U3-theraphotoxin-Lsp1a (LTx5), and ω-theraphotoxin-Asp3a as well as the proteins phospholipase A2 (PLA2) and hyaluronidase. The crude venom exhibited bactericidal effect against Aeromonas sp., Bacillus subtilis, and Micrococcus luteus and fungicidal effect against Candida parapsilosis and Candida albicans. In addition, the venom exerted bacteriostatic effect against Klebsiella pneumoniae, Pseudomonas aeruginosa, and Staphylococcus aureus and fungistatic effect against Candida tropicalis and Candida krusei. The minimum inhibitory (MIC), minimum bactericidal (MBC), and minimum fungicidal (MFC) concentrations ranged from 3.9 to 500 μg/mL. The Lasiodora sp. venom decreased the viability of human peripheral blood mononuclear cells (PBMCs) by 50%-90% at concentrations of 0.1, 1, 10, and 100 μg/mL, promoting apoptosis of these cells. On the other hand, the venom showed weak hemolytic activity against Mus musculus erythrocytes (EC50: 757 μg/mL). In conclusion, the Lasiodora sp. spider venom is a rich source of antimicrobial agents. Future studies will focus on identifying antimicrobial agents present in this venom and evaluating whether these agents contribute to its cytotoxic effects against PBMCs.

  3. Resistance to pefloxacin in Pseudomonas aeruginosa.

    PubMed Central

    Michea-Hamzehpour, M; Lucain, C; Pechere, J C

    1991-01-01

    Mechanisms of resistance to pefloxacin were investigated in four isogenic Pseudomonas aeruginosa strains: S (parent isolate; MIC, 2 micrograms/ml), PT1 and PT2 (posttherapy isolates obtained in animals; MICs, 32 and 128 micrograms/ml, respectively), and PT2-r (posttherapy isolate obtained after six in vitro subpassages of PT2; MIC, 32 micrograms/ml). [2-3H]adenine incorporation (indirect evidence of DNA gyrase activity) in EDTA-permeabilized cells was less affected by pefloxacin in PT2 and PT2-r (50% inhibitory concentration, 0.27 and 0.26 microgram/ml, respectively) than it was in S and PT1 (50% inhibitory concentration, 0.04 and 0.05 microgram/ml, respectively). Reduced [14C]pefloxacin labeling of intact cells in strains PT1 and PT2 correlated with more susceptibility to EDTA and the presence of more calcium (P less than 0.05) and phosphorus in the outer membrane fractions. Outer membrane protein analysis showed reduced expression of protein D2 (47 kDa) in strains PT1 and PT2. Other proteins were apparently similar in all strains. The addition of calcium chloride (2 mM) to the sodium dodecyl sulfate-solubilized samples of outer membrane proteins, before heating and Western blotting, probed with monoclonal antibody anti-OmpF showed electrophoretic mobility changes of OmpF in strains PT1 and PT2 which were not seen in strain S. Calcium-induced changes were reversed with ethyleneglycoltetraacetate. Decreased [14C]pefloxacin labeling was further correlated with an altered lipopolysaccharide pattern and increased 3-deoxy-D-mannooctulosonic acid concentration (P less than 0.01). These findings suggested that resistance to pefloxacin is associated with altered DNA gyrase in strain PT2-r, with altered permeability in PT1, and with both mechanisms in PT2. The decreased expression of protein D2 and the higher calcium and lipopolysaccharide contents of the outer membrane could be responsible for the permeability deficiency in P. aeruginosa. Images PMID:1645509

  4. Sp1 and the 'hallmarks of cancer'.

    PubMed

    Beishline, Kate; Azizkhan-Clifford, Jane

    2015-01-01

    For many years, transcription factor Sp1 was viewed as a basal transcription factor and relegated to a role in the regulation of so-called housekeeping genes. Identification of Sp1's role in recruiting the general transcription machinery in the absence of a TATA box increased its importance in gene regulation, particularly in light of recent estimates that the majority of mammalian genes lack a TATA box. In this review, we briefly consider the history of Sp1, the founding member of the Sp family of transcription factors. We review the evidence suggesting that Sp1 is highly regulated by post-translational modifications that positively and negatively affect the activity of Sp1 on a wide array of genes. Sp1 is over-expressed in many cancers and is associated with poor prognosis. Targeting Sp1 in cancer treatment has been suggested; however, our review of the literature on the role of Sp1 in the regulation of genes that contribute to the 'hallmarks of cancer' illustrates the extreme complexity of Sp1 functions. Sp1 both activates and suppresses the expression of a number of essential oncogenes and tumor suppressors, as well as genes involved in essential cellular functions, including proliferation, differentiation, the DNA damage response, apoptosis, senescence and angiogenesis. Sp1 is also implicated in inflammation and genomic instability, as well as epigenetic silencing. Given the apparently opposing effects of Sp1, a more complete understanding of the function of Sp1 in cancer is required to validate its potential as a therapeutic target.

  5. Differential habitat use and niche partitioning by Pseudomonas species in human homes.

    PubMed

    Remold, Susanna K; Brown, Christopher K; Farris, Justin E; Hundley, Thomas C; Perpich, Jessica A; Purdy, Megan E

    2011-10-01

    Many species of Pseudomonas have the ability to use a variety of resources and habitats, and as a result Pseudomonas are often characterized as having broad fundamental niches. We questioned whether actual habitat use by Pseudomonas species is equally broad. To do this, we sampled extensively to describe the biogeography of Pseudomonas within the human home, which presents a wide variety of habitats for microbes that live in close proximity to humans but are not part of the human flora, and for microbes that are opportunistic pathogens, such as Pseudomonas aeruginosa. From 960 samples taken in 20 homes, we obtained 163 Pseudomonas isolates. The most prevalent based on identification using the SepsiTest BLAST analysis of 16S rRNA (http://www.sepsitest-blast.de) were Pseudomonas monteilii (42 isolates), Pseudomonas plecoglossicida, Pseudomonas fulva, and P. aeruginosa (approximately 25 each). Of these, all but P. fulva differed in recovery rates among evaluated habitat types (drains, soils, water, internal vertebrate sites, vertebrate skin, inanimate surfaces, and garbage/compost) and all four species also differed in recovery rates among subcategories of habitat types (e.g., types of soils or drains). We also found that at both levels of habitat resolution, each of these six most common species (the four above plus Pseudomonas putida and Pseudomonas oryzihabitans) were over- or under-represented in some habitats relative to their contributions to the total Pseudomonas collected across all habitats. This pattern is consistent with niche partitioning. These results suggest that, whereas Pseudomonas are often characterized as generalists with broad fundamental niches, these species in fact have more restricted realized niches. Furthermore, niche partitioning driven by competition among Pseudomonas species may be contributing to the observed variability in habitat use by Pseudomonas in this system.

  6. Identification and Antibacterial Activity of Bacteria Isolated from Marine Sponge Haliclona (Reniera) sp. against Multi-Drug Resistant Human Pathogen

    NASA Astrophysics Data System (ADS)

    Ardhanu Asagabaldan, Meezan; Ayuningrum, D.; Kristiana, R.; Sabdono, A.; Radjasa, O. K.; Trianto, A.

    2017-02-01

    The marine sponge Haliclona (Reniera) sp. was a potential source of natural bioactive compounds. This sponge widely distributed along the coast of Panjang Island, Jepara, Indonesia. The aims of this research were to isolate the associated bacteria with Haliclona (Reniera) sp. and to screen the antibacterial activity against Multi-Drug Resistant (MDR) bacteria. Amount five bacteria were isolated using media selective for bacteria. The antibacterial activities of bacteria were performed by overlay methods. The bacteria strain PSP. 39-04 had the best activity against Pseudomonas aeruginosa, Staphylococcus aureus, Acinetobacter baumannii, and Enterobacter cloaceae. Based on colony morphology and phylogenetic characterization using 16S rRNA gene sequencing, PSP 39-04 was closely related with Chromohalobacter salixigens strain DSM3043.

  7. Isolation and application of Gordonia sp. JC11 for removal of boat lubricants.

    PubMed

    Chanthamalee, Jirapat; Luepromchai, Ekawan

    2012-01-01

    Boat lubricants are continuously released into the marine environment and thereby cause chronic oil pollution. This study aims to isolate lubricant-degrading microorganisms from Thai coastal areas as well as to apply a selected strain for removal of boat lubricants. Ten microorganisms in the genera of Gordonia, Microbacterium, Acinetobacter, Pseudomonas, Brucella, Enterococcus and Candida were initially isolated by crude oil enrichment culture techniques. The lubricant-removal activity of these isolates was investigated with mineral-based lubricants that had been manufactured for the 4-stroke diesel engines of fishing boats. Gordonia sp. JC11, the most effective strain was able to degrade 25-55% of 1,000 mg L(-1) total hydrocarbons in six tested lubricants, while only 0-15% of the lubricants was abiotically removed. The bacterium had many characteristics that promoted lubricant degradation such as hydrocarbon utilization ability, emulsification activity and cell surface hydrophobicity. For bioaugmentation treatment of lubricant contaminated seawater, the inoculum of Gordonia sp. JC11 was prepared by immobilizing the bacterium on polyurethane foam (PUF). PUF-immobilized Gordonia sp. JC11 was able to remove 42-56% of 100-1,000 mg L(-1) waste lubricant No. 2 within 5 days. This lubricant removal efficiency was higher than those of free cells and PUF without bacterial cells. The bioaugmentation treatment significantly increased the number of lubricant-degrading microorganisms in the fishery port seawater microcosm and resulted in rapid removal of waste lubricant No. 2.

  8. Genetic determinants involved in the biodegradation of naphthalene and phenanthrene in Pseudomonas aeruginosa PAO1.

    PubMed

    Qi, Jing; Wang, Bobo; Li, Jing; Ning, Huanhuan; Wang, Yingjuan; Kong, Weina; Shen, Lixin

    2015-05-01

    Pseudomonas sp. are predominant isolates of degradation-competent strains while very few studies have explored the degradation-related genes and pathways in most of the degrading strains. P. aeruginosa PAO1 was found capable of degrading naphthalene and phenanthrene efficiently. In order to investigate the degradation-related genes of naphthalene and phenanthrene in P. aeruginosa PAO1, a random promoter library of about 5760 strains was constructed. Thirty-two clones for differentially expressed promoters were obtained by screening in the presence of sub-inhibitory concentration of naphthalene and phenanthrene. Among them, 13 genes were up-regulated and 15 were down-regulated in the presence of naphthalene as well as phenanthrene. The four remaining genes have different regulation tendencies by naphthalene or phenanthrene. By comparing the growth between the wild type and mutants as well as the complementations, the roles of seven selected up-regulated genes on naphthalene and phenanthrene degradation were investigated. Five of the seven selected up-regulated genes, like PA2666 and PA4780, were found playing key roles on the degradation in P. aeruginosa PAO1. Also, the results imply that these genes participate in the overlapping part of naphthalene and phenanthrene degradation pathways in PAO1. Results in the article offer the convenience quick method and platform for searching degradation-related genes. It also laid a foundation for understanding of the role of the regulated genes.

  9. Biochemical characterization of a novel extended-spectrum beta-lactamase from Pseudomonas aeruginosa 802.

    PubMed

    Rejiba, Samia; Limam, Ferid; Belhadj, Cherifa; Belhadj, Omrane; Ben-Mahrez, Kamel

    2002-01-01

    Pseudomonas aeruginosa 802 was isolated at Rabta hospital in Tunis and was resistant to extended-spectrum cephalosporins and aztreonam. It produced a pI 7.6 extended-spectrum beta-lactamase (ESBL). The ESBL, named LBT 802, was purified to homogeneity by filtration on Sephadex G-75 followed by CM-Sepharose chromatography and high-performance liquid chromatography (HPLC) on a TSK-gel SP-5PW column. The LBT 802 enzyme had a molecular mass of 30 kDa. It showed a broad-substrate profile by hydrolyzing benzylpenicillin, ampicillin, cephalothin, cephaloridine, cefotaxime, ceftriaxone, and cefpirome but not ceftazidime, cefoxitin, imipenem, or aztreonam. The highest hydrolytic efficiency (Vmax/Km) was obtained for ampicillin, cephalothin, cephaloridine, and benzylpenicillin. Among extended-spectrum cephalosporins the best substrate was ceftriaxone followed by cefotaxime and cefpirome. LBT 802 activity was inhibited by clavulanic acid, sulbactam, imipenem, cefoxitin, and aztreonam. It showed its lowest Ki values for clavulanic acid, imipenem and sulbactam.

  10. Cloning and characterization of the genes for two distinct cephalosporin acylases from a Pseudomonas strain.

    PubMed Central

    Matsuda, A; Matsuyama, K; Yamamoto, K; Ichikawa, S; Komatsu, K

    1987-01-01

    Pseudomonas sp. strain SE83 converts cephalosporin C and 7 beta-(4-carboxybutanamido)cephalosporanic acid (GL-7ACA) to 7-aminocephalosporanic acid (7ACA). A DNA library of this strain was constructed in Escherichia coli and screened for the ability to deacylate GL-7ACA to 7ACA. Apparently, two distinct genes, designated acyI and acyII, were cloned on 4.8- and 6.0-kilobase-pair BglII fragments, respectively. The enzymes encoded by the two genes showed different substrate specificities, and the acyII-encoded enzyme was found to yield 7ACA from cephalosporin C by direct deacylation. Expression of the two genes in E. coli was strongly dependent on a promoter of the vector. The coding regions for acyI and acyII were localized on the 2.5- and 2.8-kilobase-pair fragments, respectively, by subcloning experiments, and high expression of both genes was obtained by placing them under the control of the lacUV5 promoter. The acyII-encoded enzyme was purified and shown to be composed of two nonidentical subunits with molecular weights of 26,000 and 57,000. Maxicell analysis revealed three acyII-specific polypeptides, two of which corresponded to the above subunits. The third polypeptide with a molecular weight of 83,000 was suggested to be the precursor of both subunits. Images PMID:2824449

  11. Antifungal activity of volatile compounds-producing Pseudomonas P2 strain against Rhizoctonia solani.

    PubMed

    Elkahoui, Salem; Djébali, Naceur; Yaich, Najeh; Azaiez, Sana; Hammami, Majdi; Essid, Rym; Limam, Ferid

    2015-01-01

    Several volatile organic compounds (VOCs) producing endophyte bacteria were isolated from the leaves of olive trees and tested for their antifungal activity against several pathogenic fungi. An antagonistic strain called P2 showed 97 % of homology with Pseudomonas sp. strains on the basis of its 16S rDNA sequence and biochemical properties. P2 strain drastically inhibited the growth of Rhizoctonia solani mycelia (86 %) at 5 day-post-confrontation (dpc) and strongly reduced fungi infection on potato slices at 10(7) bacteria ml(-1) for 3 and 7 dpc. P2 strain was also positive for protease activity as well as siderophore production. Light microscopy analysis showed that treatment of R. solani mycelia with P2 strain induced thickening of the cell-wall, vesiculation of protoplasm and blockage of fungal hyphae branching. VOCs analysis using GC-MS allowed the detection of two major products with m/z of 93.9910 and 125.9630 corresponding to dimethyl disulfide and dimethyl trisulfide respectively. VOCs-producing P2 strain could be a promising agent in the protection of tuber crops against fungal diseases.

  12. Gene cloning, expression, and substrate specificity of an imidase from the strain Pseudomonas putida YZ-26.

    PubMed

    Shi, Ya-wei; Cui, Li-fang; Yuan, Jing-ming

    2007-07-01

    A gene-encoding imidase was isolated from Pseudomonas putdia YZ-26 genomic DNA using a combination of polymerase chain reaction and activity screening the recombinant. Analysis of the nucleotide sequence revealed that an open reading frame (ORF) of 879 bp encoded a protein of 293 amino acids with a calculated molecular weight of 33712.6 kDa. The deduced amino-acid sequence showed 78% identity with the imidase from Alcaligenes eutrophus 112R4 and 80% identity with N-terminal 20 amino-acid imidase from Blastobacter sp. A17p-4. Next, the ORF was subcloned into vector pET32a to form recombinant plasmid pEI. The enzyme was overexpressed in Escherichia coli and purified to homogeneity by Ni(2+)-NTA column, with 75% activity recovery. The subunit molecular mass of the recombinant imidase as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis was approximately 36 kDa, whereas its functional unit was approximately 141 kDa with four identical subunits determined by size-exclusion chromatography. The purified enzyme showed the highest activity and affinity toward succinimide, and some other substrates, such as dihydrouracil, hydantoin, succinimide, and maleimde, were investigated.

  13. Characterization of hbzE-encoded gentisate 1,2-dioxygenase from Pseudomonas alcaligenes NCIMB 9867.

    PubMed

    Yeo, Chew Chieng; Tan, Chew Ling; Gao, Xiaoli; Zhao, Bing; Poh, Chit Laa

    2007-09-01

    Pseudomonas alcaligenes NCIMB 9867 (strain P25X) is known to synthesize two isofunctional gentisate 1,2-dioxygenases (GDO; EC 1.13.11.4) as well as other enzymes involved in the degradation of xylenols and cresols via the gentisate pathway. The hbzE gene encoding what is possibly the strictly inducible gentisate 1,2-dioxygenase II (GDO-II) was cloned, overexpressed and purified as a hexahistidine fusion protein from Escherichia coli. Active recombinant GDO-II had an estimated molecular mass of 150kDa and is likely a tetrameric protein with a subunit mass of approximately 40kDa, similar to the previously characterized gentisate 1,2-dioxygenase I (GDO-I) encoded by xlnE. However, GDO-II was unable to utilize gentisate that is substituted at the carbon-4 position, unlike GDO-I which had broader substrate specificity. GDO-II also possessed different kinetic characteristics when compared to GDO-I. The hbzE-encoded GDO-II shared higher sequence identities (53%) with GDOs from Ralstonia sp. U2 and Polaromonas naphthalenivorans CJ2, compared with only 35% identity with the xlnE-encoded GDO-I. The hbzE gene was found to be part of a cluster of nine genes including the putative regulatory gene designated hbzR, which encodes an LysR-type regulator and is divergently transcribed from the other genes of the hbzHIJKLFED cluster.

  14. Increased susceptibility to Pseudomonas aeruginosa infection under hindlimb-unloading conditions

    NASA Technical Reports Server (NTRS)

    Aviles, Hernan; Belay, Tesfaye; Fountain, Kimberly; Vance, Monique; Sonnenfeld, Gerald

    2003-01-01

    It has been reported that spaceflight conditions alter the immune system and resistance to infection [Belay T, Aviles H, Vance M, Fountain K, and Sonnenfeld G. J Allergy Clin Immunol 170: 262-268, 2002; Hankins WR and Ziegelschmid JF. In: Biomedical Results of Apollo. Washington, DC: NASA, 1975, p. 43-81. (NASA Spec. Rep. SP-368)]. Ground-based models, including the hindlimb-unloading model, have become important tools for increasing understanding of how spaceflight conditions can influence physiology. The objective of the present study was to determine the effect of hindlimb unloading on the susceptibility of mice to Pseudomonas aeruginosa infection. Hindlimb-unloaded and control mice were subcutaneously infected with 1 LD50 of P. aeruginosa. Survival, bacterial organ load, and antibody and corticosterone levels were compared among the groups. Hindlimb unloading had detrimental effects for infected mice. Animals in the hindlimb-unloaded group, compared with controls, 1). showed significantly increased mortality and reduced time to death, 2). had increased levels of corticosterone, and 3). were much less able to clear bacteria from the organs. These results suggest that hindlimb unloading may induce the production of corticosterone, which may play a critical role in the modulation of the immune system leading to increased susceptibility to P. aeruginosa infection.

  15. Rhamnolipid from Pseudomonas desmolyticum NCIM-2112 and its role in the degradation of Brown 3REL.

    PubMed

    Jadhav, Mital; Kalme, Satish; Tamboli, Dhawal; Govindwar, Sanjay

    2011-08-01

    The biosurfactant produced by Pseudomonas desmolyticum NCIM 2112 (Pd 2112) was confirmed as rhamnolipid based on the formation of dark blue halos around the colonies in CTAB-methylene blue agar plates and the content of rhamnose sugar. The average yield of rhamnolipid was 0.398 g/l/day when grown on hexadecane as sole carbon source. Pd 2112 emulsification potential associated with cell free culture broth was stable for 72 h using various hydrocarbons and vegetable oils. Chemical structure of the biosurfactant was identified as mono-rhamnolipid (Rha-C(6) -C(8) ) using HPTLC, fourier transform infrared spectroscopy, (1) H and (13) C NMR and gas chromatography-mass spectroscopy analysis. Pd 2112 mono-rhamnolipid (1 mg/ml) had increased permeabilization of Bacillus sp VUS NCIM 5342 and increased decolorization rate of textile dye Brown 3REL by 50%. Extracellular activities of lignin peroxidase and veratryl alcohol oxidase, enzymes involved in dye degradation, were significantly increased in the presence of mono-rhamnolipid by 324.5