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Sample records for enterobacter sp ysu

  1. The new species Enterobacter oryziphilus sp. nov. and Enterobacter oryzendophyticus sp. nov. are key inhabitants of the endosphere of rice

    Science.gov (United States)

    2013-01-01

    Background Six independent Gram-negative, facultatively anaerobic, non-spore-forming, nitrogen-fixing rod-shaped isolates were obtained from the root endosphere of rice grown at the International Rice Research Institute (IRRI) and investigated in a polyphasic taxonomic study. Results The strains produced fatty acid patterns typical for members of the family Enterobacteriaceae. Comparative sequence analyses of the 16S rRNA as well as rpoB genes allocated the strains to two well-defined groups within the genus Enterobacter, family Enterobacteriaceae. The analyses indicated Enterobacter radicincitans, Enterobacter arachidis and Enterobacter oryzae to be the closest related species. An RpoB (translated) protein comparison supported the placement in the genus Enterobacter and the relatedness of our isolates to the aforementioned species. Genomic DNA:DNA hybridization analyses and biochemical analyses provided further evidence that the novel strains belong to two new species within the genus Enterobacter. The two species can be differentiated from each other and from existing enteric species by acid production from L-rhamnose and D-melibiose, decarboxylation of ornithine and utilization of D-alanine, D-raffinose L-proline and L-aspartic acid, among other characteristics. Members of both species revealed capacities to colonise rice roots, including plant-growth-promoting capabilities such as an active supply of fixed nitrogen to the plant and solubilisation of inorganic phosphorus, next to traits allowing adaptation to the plant. Conclusions Two novel proposed enterobacterial species, denominated Enterobacter oryziphilus sp. nov. (type strain REICA_142T=LMG 26429T=NCCB 100393T) and Enterobacter oryzendophyticus sp. nov. (type strain REICA_082T=LMG 26432T =NCCB 100390T) were isolated from rice roots. Both species are capable of promoting rice growth by supplying nitrogen and phosphorus. PMID:23865888

  2. Enterobacter tabaci sp. nov., a novel member of the genus Enterobacter isolated from a tobacco stem.

    Science.gov (United States)

    Duan, Yan-Qing; Zhou, Xing-Kui; Di-Yan, Li; Li, Qing-Qing; Dang, Li-Zhi; Zhang, Yong-Guang; Qiu, Li-Hong; Nimaichand, Salam; Li, Wen-Jun

    2015-11-01

    A Gram-stain negative, motile, rod-shaped bacterium, designated strain YIM Hb-3(T), was isolated from the stem of a tobacco plant. The strain was observed to form convex, circular and yellow-colored colonies. The predominant respiratory quinone was identified as Q-8. The major fatty acids (>5%) detected were C(16:1)ω7c and/or C(16:1)ω6c (summed feature 3), C(16:0), C(17:0)cyclo, C(18:1)ω7c and/or C(18:1)ω6c (summed feature 8), C(14:0)3-OH and/or iso-C(16:1)I (summed feature 2), C(14:0) and C(12:0). The genomic DNA G+C content was determined to be 54.8 mol%. Phylogenetic trees based on 16S rRNA gene sequences and multilocus sequence analysis showed that strain YIM Hb-3(T) had the closest phylogenetic relationship with Enterobacter mori LMG 25706(T). DNA-DNA relatedness value between strain YIM Hb-3(T) and E. mori LMG 25706(T) was 46.9 ± 3.8%. On the basis of phenotypic and chemotaxonomic data, phylogenetic analysis, and DNA-DNA relatedness value, strain YIM Hb-3(T) is considered to represent a novel species of the genus Enterobacter, for which the name Enterobacter tabaci sp. nov. is proposed. The type strain is YIM Hb-3(T) (=KACC 17832(T) =KCTC 42694(T)).

  3. Long Chain N-acyl Homoserine Lactone Production by Enterobacter sp. Isolated from Human Tongue Surfaces

    Science.gov (United States)

    Yin, Wai-Fong; Purmal, Kathiravan; Chin, Shenyang; Chan, Xin-Yue; Chan, Kok-Gan

    2012-01-01

    We report the isolation of N-acyl homoserine lactone-producing Enterobacter sp. isolate T1-1 from the posterior dorsal surfaces of the tongue of a healthy individual. Spent supernatants extract from Enterobacter sp. isolate T1-1 activated the biosensor Agrobacterium tumefaciens NTL4(pZLR4), suggesting production of long chain AHLs by these isolates. High resolution mass spectrometry analysis of these extracts confirmed that Enterobacter sp. isolate T1-1 produced a long chain N-acyl homoserine lactone, namely N-dodecanoyl-homoserine lactone (C12-HSL). To the best of our knowledge, this is the first isolation of Enterobacter sp., strain T1-1 from the posterior dorsal surface of the human tongue and N-acyl homoserine lactones production by this bacterium. PMID:23202161

  4. Biochemical basis of mercury remediation and bioaccumulation by Enterobacter sp. EMB21.

    Science.gov (United States)

    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.

  5. Biohydrogen production by dark fermentation of glycerol using Enterobacter and Citrobacter Sp.

    Science.gov (United States)

    Maru, Biniam T; Constanti, Magda; Stchigel, Alberto M; Medina, Francesc; Sueiras, Jesus E

    2013-01-01

    Glycerol is an attractive substrate for biohydrogen production because, in theory, it can produce 3 mol of hydrogen per mol of glycerol. Moreover, glycerol is produced in substantial amounts as a byproduct of producing biodiesel, the demand for which has increased in recent years. Therefore, hydrogen production from glycerol was studied by dark fermentation using three strains of bacteria: namely, Enterobacter spH1, Enterobacter spH2, and Citrobacter freundii H3 and a mixture thereof (1:1:1). It was found that, when an initial concentration of 20 g/L of glycerol was used, all three strains and their mixture produced substantial amounts of hydrogen ranging from 2400 to 3500 mL/L, being highest for C. freundii H3 (3547 mL/L) and Enterobacter spH1 (3506 mL/L). The main nongaseous fermentation products were ethanol and acetate, albeit in different ratios. For Enterobacter spH1, Enterobacter spH2, C. freundii H3, and the mixture (1:1:1), the ethanol yields (in mol EtOH/mol glycerol consumed) were 0.96, 0.67, 0.31, and 0.66, respectively. Compared to the individual strains, the mixture (1:1:1) did not show a significantly higher hydrogen level, indicating that there was no synergistic effect. Enterobacter spH1 was selected for further investigation because of its higher yield of hydrogen and ethanol. Copyright © 2012 American Institute of Chemical Engineers (AIChE).

  6. Enterobacter muelleri sp. nov., isolated from the rhizosphere of Zea mays.

    Science.gov (United States)

    Kämpfer, Peter; McInroy, John A; Glaeser, Stefanie P

    2015-11-01

    A beige-pigmented, oxidase-negative bacterial strain (JM-458T), isolated from a rhizosphere sample, was studied using a polyphasic taxonomic approach. Cells of the isolate were rod-shaped and stained Gram-negative. A comparison of the 16S rRNA gene sequence of strain JM-458T with sequences of the type strains of closely related species of the genus Enterobacter showed that it shared highest sequence similarity with Enterobacter mori (98.7 %), Enterobacter hormaechei (98.3 %), Enterobacter cloacae subsp. dissolvens, Enterobacter ludwigii and Enterobacter asburiae (all 98.2 %). 16S rRNA gene sequence similarities to all other Enterobacter species were below 98 %. Multilocus sequence analysis based on concatenated partial rpoB, gyrB, infB and atpD gene sequences showed a clear distinction of strain JM-458T from its closest related type strains. The fatty acid profile of the strain consisted of C16 : 0, C17 : 0 cyclo, iso-C15 : 0 2-OH/C16 : 1ω7c and C18 : 1ω7c as major components. DNA-DNA hybridizations between strain JM-458T and the type strains of E. mori, E. hormaechei and E. ludwigii resulted in relatedness values of 29 % (reciprocal 25 %), 24 % (reciprocal 43 %) and 16 % (reciprocal 17 %), respectively. DNA-DNA hybridization results together with multilocus sequence analysis results and differential biochemical and chemotaxonomic properties showed that strain JM-458T represents a novel species of the genus Enterobacter, for which the name Enterobacter muelleri sp. nov. is proposed. The type strain is JM-458T ( = DSM 29346T = CIP 110826T = LMG 28480T = CCM 8546T).

  7. Enterobacter siamensis sp. nov., a transglutaminase-producing bacterium isolated from seafood processing wastewater in Thailand.

    Science.gov (United States)

    Khunthongpan, Suwannee; Bourneow, Chaiwut; H-Kittikun, Aran; Tanasupawat, Somboon; Benjakul, Soottawat; Sumpavapol, Punnanee

    2013-01-01

    A novel strain of Enterobacter, C2361(T), a Gram-negative, non-spore-forming, rod-shaped and facultative anaerobic bacterium with the capability to produce transglutaminase, was isolated from seafood processing wastewater collected from a treatment pond of a seafood factory in Songkhla Province, Thailand. Phylogenetic analyses and phenotypic characteristics, including chemotaxonomic characteristics, showed that the strain was a member of the genus Enterobacter. The 16S rRNA gene sequence similarities between strain C2361(T) and Enterobacter cloacae subsp. cloacae ATCC 13047(T) and Enterobacter cloacae subsp. dissolvens LMG 2683(T) were 97.5 and 97.5%, respectively. Strain C2361(T) showed a low DNA-DNA relatedness with the above-mentioned species. The major fatty acids were C16:0, C17:0cyclo and C14:0. The DNA G+C content was 53.0 mol%. On the basis of the polyphasic evidence gathered in this study, it should be classified as a novel species of the genus Enterobacter for which the name Enterobacter siamensis sp. nov. is proposed. The type strain is C2361(T) (= KCTC 23282(T) = NBRC 107138(T)).

  8. Bacterial cellulose synthesis mechanism of facultative anaerobe Enterobacter sp. FY-07.

    Science.gov (United States)

    Ji, Kaihua; Wang, Wei; Zeng, Bing; Chen, Sibin; Zhao, Qianqian; Chen, Yueqing; Li, Guoqiang; Ma, Ting

    2016-02-25

    Enterobacter sp. FY-07 can produce bacterial cellulose (BC) under aerobic and anaerobic conditions. Three potential BC synthesis gene clusters (bcsI, bcsII and bcsIII) of Enterobacter sp. FY-07 have been predicted using genome sequencing and comparative genome analysis, in which bcsIII was confirmed as the main contributor to BC synthesis by gene knockout and functional reconstitution methods. Protein homology, gene arrangement and gene constitution analysis indicated that bcsIII had high identity to the bcsI operon of Enterobacter sp. 638; however, its arrangement and composition were same as those of BC synthesizing operon of G. xylinum ATCC53582 except for the flanking sequences. According to the BC biosynthesizing process, oxygen is not directly involved in the reactions of BC synthesis, however, energy is required to activate intermediate metabolites and synthesize the activator, c-di-GMP. Comparative transcriptome and metabolite quantitative analysis demonstrated that under anaerobic conditions genes involved in the TCA cycle were downregulated, however, genes in the nitrate reduction and gluconeogenesis pathways were upregulated, especially, genes in three pyruvate metabolism pathways. These results suggested that Enterobacter sp. FY-07 could produce energy efficiently under anaerobic conditions to meet the requirement of BC biosynthesis.

  9. Identification and production of bioflocculants by Enterobacter sp. and Bacillus sp. and their characterization studies.

    Science.gov (United States)

    Muthulakshmi, L; Nellaiah, H; Kathiresan, T; Rajini, N; Christopher, Fenila

    2017-05-28

    In this work, two bioflocculants, namely, EB-EPS and B1-EPS, were derived from Enterobacter sp. and Bacillus sp., respectively, and analyzed with regard to their production and characterization. About 0.9 and 0.16 g of purified EB and B1 were obtained from I L of fermentation broth. Chemical analysis showed the contents of purified EB and B1 mainly as 88.7 and 92.8% (w/w) of carbohydrate, and 11.3 and 21.8% (w/w) protein, respectively. Fourier-transform infrared spectrometry analysis revealed the presence of hydroxyl, amide, and carboxyl groups in the identified bioflocculant. Thermogravimetric analysis (TGA) results exhibited enhanced thermal stability with a minimum mass loss of 50% while 25% were found to have occurred at higher temperatures (>400°C) for microbe-derived compounds EB and B1 leading to the possibility of using these compounds as fillers or for fabricating composite films for high-temperature applications. Further, the compounds from both the bacteria exhibited good antibacterial characteristics against pathogenic Escherichia coli. Degradability study of bioflocculant-embedded composite films shows the possibility of attaining eco-friendly bioremediation. Accordingly, experimental results revealed the suitability of developed composite films as a suitable alternative for food packaging and biomedical applications.

  10. Enterobacter mori sp. nov., associated with bacterial wilt on Morus alba L.

    Science.gov (United States)

    Zhu, Bo; Lou, Miao-Miao; Xie, Guan-Lin; Wang, Guo-Fen; Zhou, Qin; Wang, Fang; Fang, Yuan; Su, Ting; Li, Bin; Duan, Yong-Pin

    2011-11-01

    Two isolates of mulberry-pathogenic bacteria isolated from diseased mulberry roots were investigated in a polyphasic taxonomic study. Comparative 16S rRNA gene sequence analysis combined with rpoB gene sequence analysis allocated strains R18-2(T) and R3-3 to the genus Enterobacter, with Enterobacter asburiae, E. amnigenus, E. cancerogenus, E. cloacae subsp. cloacae, E. cloacae subsp. dissolvens and E. nimipressuralis as their closest relatives. Cells of the isolates were Gram-negative, facultatively anaerobic rods, 0.3-1.0 µm wide and 0.8-2.0 µm long, with peritrichous flagella, showing a DNA G+C content of 55.1 ± 0.5 mol%. Calculation of a similarity index based on phenotypic features and fatty acid methyl ester (FAME) analysis suggested that these isolates are members of E. cancerogenus or E. asburiae or a closely related species. Biochemical data revealed that the isolates could be differentiated from their nearest neighbours by the presence of lysine decarboxylase activity and their ability to utilize d-arabitol. DNA-DNA relatedness also distinguished the two isolates from phylogenetically closely related Enterobacter strains. Based on these data, it is proposed that the isolates represent a novel species of the genus Enterobacter, named Enterobacter mori sp. nov. The type strain is R18-2(T) ( = CGMCC 1.10322(T) = LMG 25706(T)).

  11. Bioethanol production from mannitol by a newly isolated bacterium, Enterobacter sp. JMP3.

    Science.gov (United States)

    Wang, Jing; Kim, Young Mi; Rhee, Hong Soon; Lee, Min Woo; Park, Jong Moon

    2013-05-01

    In this study a new bacterium capable of growing on brown seaweed Laminaria japonica, Enterobacter sp. JMP3 was isolated from the gut of turban shell, Batillus cornutus. In anaerobic condition, it produced high yields of ethanol (1.15 mol-EtOH mol-mannitol(-1)) as well as organic acids from mannitol, the major carbohydrate component of L. japonica. Based on carbon distribution and metabolic flux analysis, it was revealed that mannitol was more favorable than glucose for ethanol production due to their different redox states. This indicates that L. japonica is one of the promising feedstock for bioethanol production. Additionally, the mannitol dehydrogenation pathway in Enterobacter sp. JMP3 was examined and verified. Finally, an attempt was made to explore the possibility of controlling ethanol production by altering the redox potential via addition of external NADH in mannitol fermentation. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Enterobacter xiangfangensis sp. nov., isolated from Chinese traditional sourdough, and reclassification of Enterobacter sacchari Zhu et al. 2013 as Kosakonia sacchari comb. nov.

    Science.gov (United States)

    Gu, Chun Tao; Li, Chun Yan; Yang, Li Jie; Huo, Gui Cheng

    2014-08-01

    A Gram-stain-negative bacterial strain, 10-17(T), was isolated from traditional sourdough in Heilongjiang Province, China. The bacterium was characterized by a polyphasic approach, including 16S rRNA gene sequence analysis, RNA polymerase β subunit (rpoB) gene sequence analysis, DNA gyrase (gyrB) gene sequence analysis, initiation translation factor 2 (infB) gene sequence analysis, ATP synthase β subunit (atpD) gene sequence analysis, fatty acid methyl ester analysis, determination of DNA G+C content, DNA-DNA hybridization and an analysis of phenotypic features. Strain 10-17(T) was phylogenetically related to Enterobacter hormaechei CIP 103441(T), Enterobacter cancerogenus LMG 2693(T), Enterobacter asburiae JCM 6051(T), Enterobacter mori LMG 25706(T), Enterobacter ludwigii EN-119(T) and Leclercia adecarboxylata LMG 2803(T), having 99.5%, 99.3%, 98.7%, 98.5%, 98.4% and 98.4% 16S rRNA gene sequence similarity, respectively. On the basis of polyphasic characterization data obtained in the present study, a novel species, Enterobacter xiangfangensis sp. nov., is proposed and the type strain is 10-17(T) ( = LMG 27195(T) = NCIMB 14836(T) = CCUG 62994(T)). Enterobacter sacchari Zhu et al. 2013 was reclassified as Kosakonia sacchari comb. nov. on the basis of 16S rRNA, rpoB, gyrB, infB and atpD gene sequence analysis and the type strain is strain SP1(T)( = CGMCC 1.12102(T) = LMG 26783(T)). © 2014 IUMS.

  13. Genome Sequence of the Plant Growth Promoting Endophytic Bacterium Enterobacter sp. 638

    Science.gov (United States)

    Taghavi, Safiyh; van der Lelie, Daniel; Hoffman, Adam; Zhang, Yian-Biao; Walla, Michael D.; Vangronsveld, Jaco; Newman, Lee; Monchy, Sébastien

    2010-01-01

    Enterobacter sp. 638 is an endophytic plant growth promoting gamma-proteobacterium that was isolated from the stem of poplar (Populus trichocarpa×deltoides cv. H11-11), a potentially important biofuel feed stock plant. The Enterobacter sp. 638 genome sequence reveals the presence of a 4,518,712 bp chromosome and a 157,749 bp plasmid (pENT638-1). Genome annotation and comparative genomics allowed the identification of an extended set of genes specific to the plant niche adaptation of this bacterium. This includes genes that code for putative proteins involved in survival in the rhizosphere (to cope with oxidative stress or uptake of nutrients released by plant roots), root adhesion (pili, adhesion, hemagglutinin, cellulose biosynthesis), colonization/establishment inside the plant (chemiotaxis, flagella, cellobiose phosphorylase), plant protection against fungal and bacterial infections (siderophore production and synthesis of the antimicrobial compounds 4-hydroxybenzoate and 2-phenylethanol), and improved poplar growth and development through the production of the phytohormones indole acetic acid, acetoin, and 2,3-butanediol. Metabolite analysis confirmed by quantitative RT–PCR showed that, the production of acetoin and 2,3-butanediol is induced by the presence of sucrose in the growth medium. Interestingly, both the genetic determinants required for sucrose metabolism and the synthesis of acetoin and 2,3-butanediol are clustered on a genomic island. These findings point to a close interaction between Enterobacter sp. 638 and its poplar host, where the availability of sucrose, a major plant sugar, affects the synthesis of plant growth promoting phytohormones by the endophytic bacterium. The availability of the genome sequence, combined with metabolome and transcriptome analysis, will provide a better understanding of the synergistic interactions between poplar and its growth promoting endophyte Enterobacter sp. 638. This information can be further exploited to

  14. Analysis of polyhydroxyalkanoates granuales in bacillus Sp. MFD11 and enterobacter Sp. SEL2

    International Nuclear Information System (INIS)

    Naheed, N.; Jamil, N.

    2016-01-01

    Bacillus sp. MFD11 (JF901809) and Enterobacter sp. SEL2 (JF901810) were isolated from agriculture waste contaminated sites. When fed with 2% glucose as a carbon source, these bacteria produced 75.26±0.45% and 76.61±0.28% PHA of their wet weight respectively. The accumulated PHA was extracted by direct addition of sodium dodysyl sulphate in the culture medium, which yielded 52.3±0.56 micro g/l and 136.21±0.45 micro g/l PHA respectively when assayed with Crotonic acid. The PHA detection medium (PDM) provided nutrient limitation condition which favored accumulation of PHA granules. A tremendous increase in cell size was observed when strain MFD11 was grown in PDM. The size of the granules as revealed by TEM micrographs spanned from 0.1 to 1.5 micro m which is quite large as compared to the size reported in the literature 0.2 to 0.5 micro m 18). (PHA polymer was analyzed by FTIR, GC/MS and proton Nuclear magnetic resonance. The intense absorption band in the spectrum at 1724-1740 cm -1 and 1215 cm -1 to 1280 corresponding to C=O and C-O stretching group, respectively, indicated that the both strains were PHA producers. GC/MS analysis indicated that the polymer produced were copolymers of PHB-co-PHV. NMR also suggested that the extracted PHA was not a homopolymer but was the blend of copolymers with 3HV in lower abundance. Differential calorimetric thermal analysis showed melting temperature of 163 and 169 degree C for PHA produced by both strains, respectively. However, the observed melting temperature was found to be lower than the standard PHB (Signa-aldrich). (author)

  15. Hydrolysis of surimi wastewater for production of transglutaminase by Enterobacter sp. C2361 and Providencia sp. C1112.

    Science.gov (United States)

    H-Kittikun, Aran; Bourneow, Chaiwut; Benjakul, Soottawat

    2012-12-01

    Surimi wastewater (SWW) is an industrial wastewater, released during the washing step of surimi preparation from minced fish, that causes environmental problem. In this study, SWW produced from ornate threadfin bream (Nemipterus hexodon) was hydrolysed and used to cultivate Enterobacter sp. C2361 and Providencia sp. C1112 for the production of microbial transglutaminase (MTGase, EC 2.3.2.13). The SWW was repeatedly used to wash the fish mince that gained a final protein content of 3.20% (w/v). The commercial protease, Delvolase was the most appropriate protease used to produce fish protein hydrolysate (FPH) from SWW. The FPH at 40% degree of hydrolysis was used instead of a peptone portion in the SPY medium (3.0% starch, 2.0% peptone, 0.2% yeast extract, 0.2% MgSO(4), 0.2% K(2)HPO(4) and 0.2% KH(2)HPO(4), pH 7.0) to cultivate the tested strains at 37°C, shaking speed at 150rpm. Providencia sp. C1112 produced higher MTGase activity (1.78±0.05U/ml) than Streptoverticillium mobaraense (1.61±0.02U/ml) at 18h of cultivation in FPH medium. On the other hand, the Enterobacter sp. C2361 produced lower MTGase activity (1.18±0.03U/ml). Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Production of hydrogen and volatile fatty acid by Enterobacter sp. T4384 using organic waste materials.

    Science.gov (United States)

    Kim, Byung-Chun; Deshpande, Tushar R; Chun, Jongsik; Yi, Sung Chul; Kim, Hyunook; Um, Youngsoon; Sang, Byoung-In

    2013-02-01

    In a study of hydrogen-producing bacteria, strain T4384 was isolated from rice field samples in the Republic of Korea. The isolate was identified as Enterobacter sp. T4384 by phylogenetic analysis of 16S rRNA and rpoB gene sequences. Enterobacter sp. T4384 grew at a temperature range of 10-45 degrees C and at an initial pH range of 4.5-9.5. Strain T4384 produced hydrogen at 0-6% NaCl by using glucose, fructose, and mannose. In serum bottle cultures using a complete medium, Enterobacter sp. T4384 produced 1,098 ml/l H2, 4.0 g/l ethanol, and 1.0 g/l acetic acid. In a pH-regulated jar fermenter culture with the biogas removed, 2,202 ml/l H2, 6.2 g/l ethanol, and 1.0 g/l acetic acid were produced, and the lag-phase time was 4.8 h. Strain T4384 metabolized the hydrolysate of organic waste for the production of hydrogen and volatile fatty acid. The strain T4384 produced 947 ml/l H2, 3.2 g/l ethanol, and 0.2 g/l acetic acid from 6% (w/v) food waste hydrolysate; 738 ml/l H2, 4.2 g/l ethanol, and 0.8 g/l acetic acid from Miscanthus sinensis hydrolysate; and 805 ml/l H2, 5.0 g/l ethanol, and 0.7 g/l acetic acid from Sorghum bicolor hydrolysate.

  17. Statistical optimization of fermentative hydrogen production from xylose by newly isolated Enterobacter sp. CN1

    Energy Technology Data Exchange (ETDEWEB)

    Long, Chuannan; Cui, Jingjing; Liu, Zuotao; Liu, Yuntao; Hu, Zhong [Department of Biology, Shantou University, Shantou 515063 (China); Long, Minnan [The School of Energy Research, Xiamen University, Xiamen 361005 (China)

    2010-07-15

    Statistical experimental designs were applied for the optimization of medium constituents for hydrogen production from xylose by newly isolated Enterobacter sp. CN1. Using Plackett-Burman design, xylose, FeSO{sub 4} and peptone were identified as significant variables which highly influenced hydrogen production. The path of steepest ascent was undertaken to approach the optimal region of the three significant factors. These variables were subsequently optimized using Box-Behnken design of response surface methodology (RSM). The optimum conditions were found to be xylose 16.15 g/L, FeSO{sub 4} 250.17 mg/L, peptone 2.54 g/L. Hydrogen production at these optimum conditions was 1149.9 {+-} 65 ml H{sub 2}/L medium. Under different carbon sources condition, the cumulative hydrogen volume were 1217 ml H{sub 2}/L xylose medium, 1102 ml H{sub 2}/L glucose medium and 977 ml H{sub 2}/L sucrose medium; the maximum hydrogen yield were 2.0 {+-} 0.05 mol H{sub 2}/mol xylose, 0.64 mol H{sub 2}/mol glucose. Fermentative hydrogen production from xylose by Enterobacter sp. CN1 was superior to glucose and sucrose. (author)

  18. Exopolysaccharide produced by Enterobacter sp. YG4 reduces uranium induced nephrotoxicity.

    Science.gov (United States)

    K, Nagaraj; Devasya, Rekha Punchapady; Bhagwath, Arun Ananthapadmanabha

    2016-01-01

    Uranium nephrotoxicity is a health concern with very few treatment options. Bacterial exopolysaccharides (EPS) possess multiple biological activities and appear as prospective candidates for treating uranium nephrotoxicity. This study focuses on the ability of an EPS produced by a bacterial strain Enterobacter sp. YG4 to reduce uranium nephrotoxicity in vivo. This bacterium was isolated from the gut contents of a slug Laevicaulis alte (Férussac). Based on the aniline blue staining reaction and infrared spectral analysis, the EPS was identified as β-glucan and its molecular weight was 11.99×10(6)Da. The EPS showed hydroxyl radical scavenging ability and total antioxidant capacity in vitro. To assess the protection provided by the EPS against uranium nephrotoxicity, a single dose of 2mg/kg uranyl nitrate was injected intraperitoneally to albino Wistar rats. As intervention, the EPS was administered orally (100mg/kg/day) for 4 consecutive days. The rats were sacrificed on the fifth day and analyses were conducted. Increased serum creatinine and urea nitrogen levels and histopathological alterations in kidneys were observed in uranyl nitrate treated animals. All these alterations were reduced with the administration of Enterobacter sp. YG4 EPS, emphasizing a novel approach in treating uranium nephrotoxicity. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. A halotolerant Enterobacter sp. displaying ACC deaminase activity promotes rice seedling growth under salt stress.

    Science.gov (United States)

    Sarkar, Anumita; Ghosh, Pallab Kumar; Pramanik, Krishnendu; Mitra, Soumik; Soren, Tithi; Pandey, Sanjeev; Mondal, Monohar Hossain; Maiti, Tushar Kanti

    2018-01-01

    Agricultural productivity is proven to be hampered by the synthesis of reactive oxygen species (ROS) and production of stress-induced ethylene under salinity stress. One-aminocyclopropane-1-carboxylic acid (ACC) is the direct precursor of ethylene synthesized by plants. Bacteria possessing ACC deaminase activity can use ACC as a nitrogen source preventing ethylene production. Several salt-tolerant bacterial strains displaying ACC deaminase activity were isolated from rice fields, and their plant growth-promoting (PGP) properties were determined. Among them, strain P23, identified as an Enterobacter sp. based on phenotypic characteristics, matrix-assisted laser desorption ionization-time of flight mass spectrometry data and the 16S rDNA sequence, was selected as the best-performing isolate for several PGP traits, including phosphate solubilization, IAA production, siderophore production, HCN production, etc. Enterobacter sp. P23 was shown to promote rice seedling growth under salt stress, and this effect was correlated with a decrease in antioxidant enzymes and stress-induced ethylene. Isolation of an acdS mutant strain enabled concluding that the reduction in stress-induced ethylene content after inoculation of strain P23 was linked to ACC deaminase activity. Copyright © 2017 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  20. Draft Genome Sequence of Enterobacter sp. Sa187, an Endophytic Bacterium Isolated from the Desert Plant Indigofera argentea

    KAUST Repository

    Lafi, Feras Fawzi; Alam, Intikhab; Geurts, Rene; Bisseling, Ton; Bajic, Vladimir B.; Hirt, Heribert; Saad, Maged

    2017-01-01

    Enterobacter sp. Sa187 is a plant endophytic bacterium, isolated from root nodules of the desert plant Indigofera argentea, collected from the Jizan region of Saudi Arabia. Here, we report the genome sequence of Sa187, highlighting several genes involved in plant growth–promoting activity and environmental adaption.

  1. Draft genome sequence of Enterobacter sp. Sa187, an endophytic bacterium isolated from the desert plant Indigofera argentea

    NARCIS (Netherlands)

    Lafi, Feras F.; Alam, Intikhab; Geurts, Rene; Bisseling, Ton; Bajic, Vladimir B.; Hirt, Heribert; Saad, Maged M.

    2017-01-01

    Enterobacter sp. Sa187 is a plant endophytic bacterium, isolated from root nodules of the desert plant Indigofera argentea, collected from the Jizan region of Saudi Arabia. Here, we report the genome sequence of Sa187, highlighting several genes involved in plant growth-promoting activity and

  2. Biosorption of lead, copper and cadmium by an indigenous isolate Enterobacter sp. J1 possessing high heavy-metal resistance

    International Nuclear Information System (INIS)

    Lu, W.-B.; Shi, J.-J.; Wang, C.-H.; Chang, J.-S.

    2006-01-01

    This study was undertaken to investigate biosorption kinetics and equilibria of lead (Pb), copper (Cu) and cadmium (Cd) ions using the biomass of Enterobacter sp. J1 isolated from a local industry wastewater treatment plant. Efficiency of metal ion recovery from metal-loaded biomass to regenerate the biosorbent was also determined. The results show that Enterobacter sp. J1 was able to uptake over 50 mg of Pb per gram of dry cell, while having equilibrium adsorption capacities of 32.5 and 46.2 mg/g dry cell for Cu and Cd, respectively. In general, Langmuir and Freundlich models were able to describe biosorption isotherm fairly well, except that prediction of Pb adsorption was relatively poor with Langmuir model, suggesting a different mechanism for Pb biosorption. Adjusting the pH value to 3.0 led to nearly complete desorption of Cd from metal-loaded biomass, while over 90% recovery of Pb and Cu ions was obtained at pH ≤ 2. After four repeated adsorption/desorption cycles, biomass of Enterobacter sp. J1 retained 75, 79 and 90% of original capacity for adsorption of Pb, Cu and Cd, respectively, suggesting good reusability of the biosorbent. A combinative model was proposed to describe the kinetics of heavy-metal adsorption by Enterobacter sp. J1 and the model appeared to have an excellent prediction of the experimental data. The model simulation results also seemed to suggest that intracellular accumulation may occur during the uptake of Pb

  3. Plant growth promotion and root colonization by EPS producing Enterobacter sp. RZS5 under heavy metal contaminated soil.

    Science.gov (United States)

    Sayyed, R Z; Patel, P R; Shaikh, S S

    2015-02-01

    The heavy metal resistant bacterium isolated from field soil and identified as Enterobacter sp. RZS5 tolerates a high concentration (100-2000 μM) of various heavy metal ions such as Mn2+, Ni2+, Zn2+, Cu2+, CO2+ and Fe2+ when grown in such environment and produces exopolysaccharides (EPS). Here, we have demonstrated EPS production by Enterobacter sp. RZS5 during 60 h of growth in yeast extract mannitol broth (YEMB). The yield increased by two fold after the addition of 60 μM of Ca2+; 50 μM of Fe2+ and 60 μM of Mg2+ ions in YEMB, and the optimization of physico-chemical parameters. EPS was extracted with 30% (v/v) of isopropanol as against the commonly used 50% (v/v) isopropanol method. EPS-rich broth promoted seed germination, shoot height, root length, number of leaves and chlorophyll content of wheat (Triticum aestivum) seed and peanut (Arachis hypogaea) seed. The higher colony-forming unit of Enterobacter sp. in soil inoculated with EPS rich broth of Enterobacter sp. indicated the root colonizing potential and rhizosphere competence of the isolate. The FTIR spectra of the EPS extract confirmed the presence of the functional group characteristics of EPS known to exhibit a high binding affinity towards certain metal ions. This overall growth and vigour in plants along with the effective root colonization, reflected the potential of the isolate as an efficient bio-inoculant in bioremediation.

  4. Biosorption of lead, copper and cadmium by an indigenous isolate Enterobacter sp. J1 possessing high heavy-metal resistance

    Energy Technology Data Exchange (ETDEWEB)

    Lu, W.-B. [Department of Cosmetic Science, Chung Hwa College of Medical Technology, Tainan, Taiwan (China); Shi, J.-J. [Department of Chemical Engineering, National Cheng Kung University, Tainan, Taiwan (China); Wang, C.-H. [Department of Biological Engineering, Yung Ta Institute of Technology and Commerce, Pingtung, Taiwan (China); Chang, J.-S. [Department of Chemical Engineering, National Cheng Kung University, Tainan, Taiwan (China)]. E-mail: changjs@mail.ncku.edu.tw

    2006-06-30

    This study was undertaken to investigate biosorption kinetics and equilibria of lead (Pb), copper (Cu) and cadmium (Cd) ions using the biomass of Enterobacter sp. J1 isolated from a local industry wastewater treatment plant. Efficiency of metal ion recovery from metal-loaded biomass to regenerate the biosorbent was also determined. The results show that Enterobacter sp. J1 was able to uptake over 50 mg of Pb per gram of dry cell, while having equilibrium adsorption capacities of 32.5 and 46.2 mg/g dry cell for Cu and Cd, respectively. In general, Langmuir and Freundlich models were able to describe biosorption isotherm fairly well, except that prediction of Pb adsorption was relatively poor with Langmuir model, suggesting a different mechanism for Pb biosorption. Adjusting the pH value to 3.0 led to nearly complete desorption of Cd from metal-loaded biomass, while over 90% recovery of Pb and Cu ions was obtained at pH {<=} 2. After four repeated adsorption/desorption cycles, biomass of Enterobacter sp. J1 retained 75, 79 and 90% of original capacity for adsorption of Pb, Cu and Cd, respectively, suggesting good reusability of the biosorbent. A combinative model was proposed to describe the kinetics of heavy-metal adsorption by Enterobacter sp. J1 and the model appeared to have an excellent prediction of the experimental data. The model simulation results also seemed to suggest that intracellular accumulation may occur during the uptake of Pb.

  5. Root colonization and growth promotion of sunflower (Helianthus annuus L.) by phosphate solubilizing Enterobacter sp. Fs-11

    NARCIS (Netherlands)

    Shahid, Muhammad; Hameed, Sohail; Imran, Asma; Ali, Saira; van Elsas, Jan Dirk

    An Enterobacter sp. Fs-11 was isolated from sunflower rhizosphere, identified on the basis of 16S rRNA gene sequence analysis (GeneBank accession no. GQ179978) and studied for its root colonization and growth promotion ability in sunflower. Morphologically, it was rod shaped Gram-negative, motile

  6. Draft Genome Sequence of Enterobacter sp. Sa187, an Endophytic Bacterium Isolated from the Desert Plant Indigofera argentea

    KAUST Repository

    Lafi, Feras Fawzi

    2017-02-17

    Enterobacter sp. Sa187 is a plant endophytic bacterium, isolated from root nodules of the desert plant Indigofera argentea, collected from the Jizan region of Saudi Arabia. Here, we report the genome sequence of Sa187, highlighting several genes involved in plant growth–promoting activity and environmental adaption.

  7. Cloning and characterization of newly isolated lipase from Enterobacter sp. Bn12.

    Science.gov (United States)

    Farrokh, Parisa; Yakhchali, Bagher; Karkhane, Ali Asghar

    2014-01-01

    A mesophilic Enterobacter sp. Bn12 producing an alkaline thermostable lipase was isolated from soil in Tehran, Iran. The lipase gene (ELBn12) was identified from a genomic library. Sequence analysis of the DNA fragment revealed an open reading frame of 879 bp encoding a lipase with a molecular mass of 31.3 kDa. The deduced amino acid sequence showed 96% identity with a lipase of Enterobacter sp. Ag1 and the identity of their DNA sequences was 88.9%. ELBn12 belongs to the lipase subfamily I.1 and its catalytic triad consists of Ser82, Asp237 and His259. The lipase was expressed in Escherichia coli (BL21) pLysS and partially purified by anion exchange chromatography. The maximum activity of ELBn12 was obtained at temperature of 60 °C and pH 8.0 towards tricaprylin (C8) and its specific activity was around 2900 U/mg. ELBn12 was stable within a broad pH range from 6.0 to 11.0. The enzyme showed high stability in both polar and nonpolar organic solvents at 50% (v/v). The lipase activity was enhanced in the presence of 10 mM of Ca(2+), Mg(2+) and K(+), while heavy metals (Fe(3+) and Zn(2+)) had strong inhibitory effect. ELBn12 showed high activity in the presence of 1% (w/v) nonionic surfactants, however ionic surfactants inhibited the lipolytic activity. ELBn12 characteristics show that it has a potential to be used in various industrial processes.

  8. Enterobacter sp. LU1 as a novel succinic acid producer - co-utilization of glycerol and lactose.

    Science.gov (United States)

    Podleśny, Marcin; Jarocki, Piotr; Wyrostek, Jakub; Czernecki, Tomasz; Kucharska, Jagoda; Nowak, Anna; Targoński, Zdzisław

    2017-03-01

    Succinic acid is an important C4-building chemical platform for many applications. A novel succinic acid-producing bacterial strain was isolated from goat rumen. Phylogenetic analysis based on the 16S rRNA sequence and physiological analysis indicated that the strain belongs to the genus Enterobacter. This is the first report of a wild bacterial strain from the genus Enterobacter that is capable of efficient succinic acid production. Co-fermentation of glycerol and lactose significantly improved glycerol utilization under anaerobic conditions, debottlenecking the utilization pathway of this valuable biodiesel waste product. Succinic acid production reached 35 g l -1 when Enterobacter sp. LU1 was cultured in medium containing 50 g l -1 of glycerol and 25 g l -1 of lactose as carbon sources. © 2016 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  9. Dark fermentative hydrogen and ethanol production from biodiesel waste glycerol using a co-culture of Escherichia coli and Enterobacter sp.

    NARCIS (Netherlands)

    Maru, B.T.; López, F.; Kengen, S.W.M.; Constantí, M.; Medina, F.

    2016-01-01

    In previous comparative studies, Enterobacter spH1 was selected as the best hydrogen and ethanol producer (Knothe, 2010). Here, glycerol fermentation was compared between three other strains: Escherichia coli CECT432, Escherichia coli CECT434 and Enterobacter cloacae MCM2/1. E. coli CECT432 was

  10. Transcriptional responses to sucrose mimic the plant-associated life style of the plant growth promoting endophyte Enterobacter sp. 638.

    Science.gov (United States)

    Taghavi, Safiyh; Wu, Xiao; Ouyang, Liming; Zhang, Yian Biao; Stadler, Andrea; McCorkle, Sean; Zhu, Wei; Maslov, Sergei; van der Lelie, Daniel

    2015-01-01

    Growth in sucrose medium was previously found to trigger the expression of functions involved in the plant associated life style of the endophytic bacterium Enterobacter sp. 638. Therefore, comparative transcriptome analysis between cultures grown in sucrose or lactate medium was used to gain insights in the expression levels of bacterial functions involved in the endophytic life style of strain 638. Growth on sucrose as a carbon source resulted in major changes in cell physiology, including a shift from a planktonic life style to the formation of bacterial aggregates. This shift was accompanied by a decrease in transcription of genes involved in motility (e.g., flagella biosynthesis) and an increase in the transcription of genes involved in colonization, adhesion and biofilm formation. The transcription levels of functions previously suggested as being involved in endophytic behavior and functions responsible for plant growth promoting properties, including the synthesis of indole-acetic acid, acetoin and 2,3-butanediol, also increased significantly for cultures grown in sucrose medium. Interestingly, despite an abundance of essential nutrients transcription levels of functions related to uptake and processing of nitrogen and iron became increased for cultures grown on sucrose as sole carbon source. Transcriptome data were also used to analyze putative regulatory relationships. In addition to the small RNA csrABCD regulon, which seems to play a role in the physiological adaptation and possibly the shift between free-living and plant-associated endophytic life style of Enterobacter sp. 638, our results also pointed to the involvement of rcsAB in controlling responses by Enterobacter sp. 638 to a plant-associated life style. Targeted mutagenesis was used to confirm this role and showed that compared to wild-type Enterobacter sp. 638 a ΔrcsB mutant was affected in its plant growth promoting ability.

  11. Transcriptional responses to sucrose mimic the plant-associated life style of the plant growth promoting endophyte Enterobacter sp. 638.

    Directory of Open Access Journals (Sweden)

    Safiyh Taghavi

    Full Text Available Growth in sucrose medium was previously found to trigger the expression of functions involved in the plant associated life style of the endophytic bacterium Enterobacter sp. 638. Therefore, comparative transcriptome analysis between cultures grown in sucrose or lactate medium was used to gain insights in the expression levels of bacterial functions involved in the endophytic life style of strain 638. Growth on sucrose as a carbon source resulted in major changes in cell physiology, including a shift from a planktonic life style to the formation of bacterial aggregates. This shift was accompanied by a decrease in transcription of genes involved in motility (e.g., flagella biosynthesis and an increase in the transcription of genes involved in colonization, adhesion and biofilm formation. The transcription levels of functions previously suggested as being involved in endophytic behavior and functions responsible for plant growth promoting properties, including the synthesis of indole-acetic acid, acetoin and 2,3-butanediol, also increased significantly for cultures grown in sucrose medium. Interestingly, despite an abundance of essential nutrients transcription levels of functions related to uptake and processing of nitrogen and iron became increased for cultures grown on sucrose as sole carbon source. Transcriptome data were also used to analyze putative regulatory relationships. In addition to the small RNA csrABCD regulon, which seems to play a role in the physiological adaptation and possibly the shift between free-living and plant-associated endophytic life style of Enterobacter sp. 638, our results also pointed to the involvement of rcsAB in controlling responses by Enterobacter sp. 638 to a plant-associated life style. Targeted mutagenesis was used to confirm this role and showed that compared to wild-type Enterobacter sp. 638 a ΔrcsB mutant was affected in its plant growth promoting ability.

  12. Bio-herbicide effect of salt marsh tolerant Enterobacter sp. I-3 on weed seed germination and seedling growth

    International Nuclear Information System (INIS)

    Radhakrishan, R.; Lee, I.J.

    2017-01-01

    Weeds are major challenges in crop cultivation and cause yield loss. The bacteria based bio-herbicides are emerging against chemical herbicides. This study was aimed to explore the bio-herbicide effect of salt marsh tolerant Enterobacter sp. I-3 on various weed species. The efficacy of I-3 bacterial isolates against weed growth was compared with I-4-5 bacterial strain. The bacterial strains, I-3 and I-4-5 inhibited the seed germination of Cyperus microiria Maxim. Enterobacter sp. I-3 showed higher weed control activity than I-4-5. It was confirmed with growth reduction of C. microiria Maxim. The seed germination of Digitaria sanguinalis L. weed was accelerated during the interaction of I-4-5 and it was drastically declined by I-3 bacterial culture. However, Alopecurus aequalis Sobol. seeds treated with either I-3 or I-4-5 bacterial culture showed no significant germination inhibition. The results of this study suggested that salt marsh tolerant Enterobacter sp. I-3 can be applied as bacterial herbicides to control weeds in agricultural fields. (author)

  13. Biodegradation and detoxification of chlorimuron-ethyl by Enterobacter ludwigii sp. CE-1.

    Science.gov (United States)

    Pan, Xiong; Wang, Saige; Shi, Nan; Fang, Hua; Yu, Yunlong

    2018-04-15

    The application of the herbicide chlorimuron-ethyl has a lasting toxic effect on some succession crops. Here, a bacterium capable of utilizing chlorimuron-ethyl as the sole source of nitrogen was isolated from the contaminated soil and was identified as Enterobacter ludwigii sp. CE-1, and its detoxification and degradation of the herbicide were then examined. The biodegradation of chlorimuron-ethyl by the isolate CE-1 was significantly accelerated with increasing concentration (1-10mg/l) and temperature (20-40°C). The optimal pH for the degradation of chlorimuron-ethyl by the isolate CE-1 was pH 7.0. A pathway for the biodegradation of chlorimuron-ethyl by the isolate CE-1 was proposed, in which it could be first converted into 2-amino-4-chloro-6-methoxypyrimidine and an intermediate product by the cleavage of the sulfonylurea bridge and then transformed into saccharin via hydrolysis and amidation. The plant height and fresh weight of corn that had been incubated in nutrient solution containing 0.2mg/l of chlorimuron-ethyl significantly recovered to 83.9% and 83.1% compared with those in the uninoculated control, although the root growth inhibition of chlorimuron-ethyl could not be alleviated after inoculation for 14 d. The results indicate that the isolate CE-1 is a promising bacterial resource for the biodegradation and detoxification of chlorimuron-ethyl. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Production, characteristics and applications of phytase from a rhizosphere isolated Enterobacter sp. ACSS.

    Science.gov (United States)

    Chanderman, Ashira; Puri, Adarsh Kumar; Permaul, Kugen; Singh, Suren

    2016-10-01

    Optimization of process parameters for phytase production by Enterobacter sp. ACSS led to a 4.6-fold improvement in submerged fermentation, which was enhanced further in fed-batch fermentation. The purified 62 kDa monomeric phytase was optimally active at pH 2.5 and 60 °C and retained activity over a wide range of temperature (40-80 °C) and pH (2.0-6.0) with a half-life of 11.3 min at 80 °C. The kinetic parameters K m, V max, K cat, and K cat/K m of the pure phytase were 0.21 mM, 131.58 nmol mg(-1) s(-1), 1.64 × 10(3) s(-1), and 7.81 × 10(6) M(-1) s(-1), respectively. The enzyme was fairly stable in the presence of pepsin under physiological conditions. It was stimulated by Ca(+2), Mg(+2) and Mn(+2), but inhibited by Zn(+2), Cu(+2), Fe(+2), Pb(+2), Ba(+2) and surfactants. The enzyme can be applied in dephytinizing animal feeds, and the baking industry.

  15. Survival Strategies of the Plant-Associated Bacterium Enterobacter sp. Strain EG16 under Cadmium Stress.

    Science.gov (United States)

    Chen, Yanmei; Chao, Yuanqing; Li, Yaying; Lin, Qingqi; Bai, Jun; Tang, Lu; Wang, Shizhong; Ying, Rongrong; Qiu, Rongliang

    2016-01-04

    Plant-associated bacteria are of great interest because of their potential use in phytoremediation. However, their ability to survive and promote plant growth in metal-polluted soils remains unclear. In this study, a soilborne Cd-resistant bacterium was isolated and identified as Enterobacter sp. strain EG16. It tolerates high external Cd concentrations (Cd(2+) MIC, >250 mg liter(-1)) and is able to produce siderophores and the plant hormone indole-3-acetic acid (IAA), both of which contribute to plant growth promotion. Surface biosorption in this strain accounted for 31% of the total Cd accumulated. The potential presence of cadmium sulfide, shown by energy-dispersive X-ray (EDX) analysis, suggested intracellular Cd binding as a Cd response mechanism of the isolate. Cd exposure resulted in global regulation at the transcriptomic level, with the bacterium switching to an energy-conserving mode by inhibiting energy-consuming processes while increasing the production of stress-related proteins. The stress response system included increased import of sulfur and iron, which become deficient under Cd stress, and the redirection of sulfur metabolism to the maintenance of intracellular glutathione levels in response to Cd toxicity. Increased production of siderophores, responding to Cd-induced Fe deficiency, not only is involved in the Cd stress response systems of EG16 but may also play an important role in promoting plant growth as well as alleviating the Cd-induced inhibition of IAA production. The newly isolated strain EG16 may be a suitable candidate for microbially assisted phytoremediation due to its high resistance to Cd and its Cd-induced siderophore production, which is likely to contribute to plant growth promotion. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  16. Auto-aggregation properties of a novel aerobic denitrifier Enterobacter sp. strain FL.

    Science.gov (United States)

    Wang, Xia; An, Qiang; Zhao, Bin; Guo, Jin Song; Huang, Yuan Sheng; Tian, Meng

    2018-02-01

    Enterobacter sp. strain FL was newly isolated from activated sludge and exhibited significant capability of auto-aggregation as well as aerobic denitrification. The removal efficiencies of NO 3 - -N, total nitrogen (TN), and TOC by strain FL in batch culture reached 94.6, 63.9, and 72.5% in 24 h, respectively. The production of N 2 O and N 2 in the presence of oxygen demonstrated the occurrence of aerobic denitrification. The auto-aggregation index of strain FL reached 54.3%, suggesting a high tendency that the cells would agglomerate into aggregates. The production of extracellular polymeric substances (EPSs), which were mainly composed of proteins followed by polysaccharides, was considered to be related to the cell aggregation according to Fourier transform infrared (FT-IR) and confocal laser scanning microscopy (CLSM). The proteins in EPS were evenly and tightly combined to cells and altered the protein secondary structures of cell surface from random coils to β-sheets and three-turn helices. The alteration of protein secondary structures of cell surface caused by the proteins in EPS might play a dominant role in the auto-aggregation of strain FL. To further assess the feasibility of strain FL for synthetic wastewater treatment, a sequencing batch reactor (SBR), solely inoculated with strain FL, was conducted. During the 16 running cycles, the removal efficiency of NO 3 - -N was 90.2-99.7% and the auto-aggregation index was stabilized at 35.0-41.5%. The EPS promoted the biomass of strain FL to aggregate in the SBR.

  17. Isolation of high-salinity-tolerant bacterial strains, Enterobacter sp., Serratia sp., Yersinia sp., for nitrification and aerobic denitrification under cyanogenic conditions.

    Science.gov (United States)

    Mpongwana, N; Ntwampe, S K O; Mekuto, L; Akinpelu, E A; Dyantyi, S; Mpentshu, Y

    2016-01-01

    Cyanides (CN(-)) and soluble salts could potentially inhibit biological processes in wastewater treatment plants (WWTPs), such as nitrification and denitrification. Cyanide in wastewater can alter metabolic functions of microbial populations in WWTPs, thus significantly inhibiting nitrifier and denitrifier metabolic processes, rendering the water treatment processes ineffective. In this study, bacterial isolates that are tolerant to high salinity conditions, which are capable of nitrification and aerobic denitrification under cyanogenic conditions, were isolated from a poultry slaughterhouse effluent. Three of the bacterial isolates were found to be able to oxidise NH(4)-N in the presence of 65.91 mg/L of free cyanide (CN(-)) under saline conditions, i.e. 4.5% (w/v) NaCl. The isolates I, H and G, were identified as Enterobacter sp., Yersinia sp. and Serratia sp., respectively. Results showed that 81% (I), 71% (G) and 75% (H) of 400 mg/L NH(4)-N was biodegraded (nitrification) within 72 h, with the rates of biodegradation being suitably described by first order reactions, with rate constants being: 4.19 h(-1) (I), 4.21 h(-1) (H) and 3.79 h(-1) (G), respectively, with correlation coefficients ranging between 0.82 and 0.89. Chemical oxygen demand (COD) removal rates were 38% (I), 42% (H) and 48% (G), over a period of 168 h with COD reduction being highest at near neutral pH.

  18. Isolation and characterization of a novel 2-methyl-4-chlorophenoxyacetic acid-degrading Enterobacter sp. strain SE08.

    Science.gov (United States)

    Tan, Lin; Hu, Qiulong; Xiong, Xingyao; Su, Xiaojun; Huang, Yanning; Jiang, Ziwei; Zhou, Qingming; Zhao, Songyi; Zeng, Wei-ai

    2013-10-01

    A bacterial strain (SE08) capable of utilizing 2-methyl-4-chlorophenoxy acetic acid (MCPA) as the sole carbon and energy source for growth was isolated by continuous enrichment culturing in minimal salt medium (MSM) from a long term MCPA exposed soil. This bacterial strain was identified as Enterobacter sp. based on morphological, physiological and biochemical tests, as well as 16S rRNA sequence analysis. Its ability to degrade MCPA was determined using high performance liquid chromatography. The strain SE08 can tolerate unusually high MCPA concentrations (125-2000mg/L). The influences of culturing factors (initial concentration, pH, and temperature) on the bacterial growth and substrate degradation were studied. The results showed that the optimal MCPA degradation occurred at an MCPA concentration of 500mg/L, 30°C and pH 6.0. Under these conditions, 68.5 percent of MCPA in MSM was degraded by SE08, and the OD600nm reached 0.64 after culturing for 72h. The degradation of MCPA could be enhanced by addition of both carbon and nitrogen sources. At an initial MCPA concentration of 500mg/L, when 5g/L glucose and 2.5g/L yeast extract were added into the MSM media, the MCPA degradation was significantly increased to 83.8 percent, and OD600nm was increased to 1.09 after incubation at 30°C and pH 6.0 for 72h. This is the first study showing that an Enterobacter sp. strain is capable of degrading MCPA, which might provide a new approach for the remediation of MCPA contaminated soil and contribute to the limited knowledge about the function of Enterobacter species. Crown Copyright © 2013. Published by Elsevier Inc. All rights reserved.

  19. Exploring multi-metal biosorption by indigenous metal-hyperresistant Enterobacter sp. J1 using experimental design methodologies

    International Nuclear Information System (INIS)

    Lu, W.-B.; Kao, W.-C.; Shi, J.-J.; Chang, J.-S.

    2008-01-01

    A novel experimental design, combining mixture design and response surface methodology (RSM), was developed to investigate the competitive adsorption behavior of lead, copper and cadmium by an indigenous isolate Enterobacter sp. J1 able to tolerate high concentrations of a variety of heavy metals. Using the proposed combinative experimental design, two different experiment designs in a ternary metal biosorption system can be integrated to a succinct experiment and the number of experimental trials was markedly reduced from 38 to 26 by reusing the mutual experimental data. Triangular contour diagrams and triangular three-dimensional surface plots were generated to describe the ternary metal biosorption equilibrium data in mixture design systems. The results show that the preference of metal sorption of Enterobacter sp. J1 decreased in the order of Pb 2+ > Cu 2+ > Cd 2+ . The presence of other metals resulted in a competitive effect. The influence of the other two metals in ternary metal biosorption system can be easily determined by comparing the stray distance from the single metal biosorption. The behavior of competitive biosorption was successfully described and predicted using a combined Langmuir-Freundlich model along with new three-dimensional contour-surface plots

  20. Exploring multi-metal biosorption by indigenous metal-hyperresistant Enterobacter sp. J1 using experimental design methodologies

    Energy Technology Data Exchange (ETDEWEB)

    Lu, W.-B. [Department of Cosmetic Science, Chung Hwa University of Medical Technology, Tainan, Taiwan (China); Kao, W.-C.; Shi, J.-J. [Department of Chemical Engineering, National Cheng Kung University, Tainan, Taiwan (China); Chang, J.-S. [Department of Chemical Engineering, National Cheng Kung University, Tainan, Taiwan (China)], E-mail: changjs@mail.ncku.edu.tw

    2008-05-01

    A novel experimental design, combining mixture design and response surface methodology (RSM), was developed to investigate the competitive adsorption behavior of lead, copper and cadmium by an indigenous isolate Enterobacter sp. J1 able to tolerate high concentrations of a variety of heavy metals. Using the proposed combinative experimental design, two different experiment designs in a ternary metal biosorption system can be integrated to a succinct experiment and the number of experimental trials was markedly reduced from 38 to 26 by reusing the mutual experimental data. Triangular contour diagrams and triangular three-dimensional surface plots were generated to describe the ternary metal biosorption equilibrium data in mixture design systems. The results show that the preference of metal sorption of Enterobacter sp. J1 decreased in the order of Pb{sup 2+} > Cu{sup 2+} > Cd{sup 2+}. The presence of other metals resulted in a competitive effect. The influence of the other two metals in ternary metal biosorption system can be easily determined by comparing the stray distance from the single metal biosorption. The behavior of competitive biosorption was successfully described and predicted using a combined Langmuir-Freundlich model along with new three-dimensional contour-surface plots.

  1. Biological reduction of hexavalent chromium and mechanism analysis of detoxification by enterobacter sp. HT1 isolated from tannery effluents, Mongolia

    Directory of Open Access Journals (Sweden)

    N Marjangul

    2014-12-01

    Full Text Available Enterobacter sp. HT1, Cr (VI resistant bacterial strain was isolated from the wastewater sample of the tannery in Mongolia. Batch experiments on hexavalent chromium removal was carried out at 10, 20, and 30 mg/L of Cr (VI added as potassium dichromate (K2Cr2O7, at pH 7 and temperature of 30 °C using pure culture of Enterobacter sp. HT1 as inoculum.  The isolated HT1 is capable of reduction nearly 100% of Cr (VI resulting in the decrease of Cr (VI from 10 to 0.2 mg/L within 20 hours. When the concentration of Cr (VI increased to 20 and 30mg/L, almost complete reduction of Cr (VI could achieve after 72 and 96 hours, respectively.DOI: http://doi.dx.org/10.5564/mjc.v15i0.322 Mongolian Journal of Chemistry 15 (41, 2014, p47-52

  2. Clonality, outer-membrane proteins profile and efflux pump in KPC- producing Enterobacter sp. in Brazil.

    Science.gov (United States)

    Rosa, Juliana Ferraz; Rizek, Camila; Marchi, Ana Paula; Guimaraes, Thais; Miranda, Lourdes; Carrilho, Claudia; Levin, Anna S; Costa, Silvia F

    2017-03-17

    Carbapenems resistance in Enterobacter spp. has increased in the last decade, few studies, however, described the mechanisms of resistance in this bacterium. This study evaluated clonality and mechanisms of carbapenems resistance in clinical isolates of Enterobacter spp. identified in three hospitals in Brazil (Hospital A, B and C) over 7-year. Antibiotics sensitivity, pulsed-field gel electrophoresis (PFGE), PCR for carbapenemase and efflux pump genes were performed for all carbapenems-resistant isolates. Outer-membrane protein (OMP) was evaluated based on PFGE profile. A total of 130 isolates of Enterobacter spp were analyzed, 44/105 (41, 9%) E. aerogenes and 8/25 (32,0%) E. cloacae were resistant to carbapenems. All isolates were susceptible to fosfomycin, polymyxin B and tigecycline. KPC was present in 88.6% of E. aerogenes and in all E. cloacae resistant to carbapenems. The carbapenems-resistant E. aerogenes identified in hospital A belonged to six clones, however, a predominant clone was identified in this hospital over the study period. There is a predominant clone in Hospital B and Hospital C as well. The mechanisms of resistance to carbapenems differ among subtypes. Most of the isolates co-harbored blaKPC, blaTEM and /or blaCTX associated with decreased or lost of 35-36KDa and or 39 KDa OMP. The efflux pump AcrAB-TolC gene was only identified in carbapenems-resistant E. cloacae. There was a predominant clone in each hospital suggesting that cross-transmission of carbapenems-resistant Enterobacter spp. was frequent. The isolates presented multiple mechanisms of resistance to carbapenems including OMP alteration.

  3. Purification and characterization of a GH43 β-xylosidase from Enterobacter sp. identified and cloned from forest soil bacteria.

    Science.gov (United States)

    Campos, Eleonora; Negro Alvarez, María José; Sabarís di Lorenzo, Gonzalo; Gonzalez, Sergio; Rorig, Marcela; Talia, Paola; Grasso, Daniel H; Sáez, Felicia; Manzanares Secades, Paloma; Ballesteros Perdices, Mercedes; Cataldi, Angel A

    2014-01-01

    The use of lignocellulosic biomass for second generation biofuels requires optimization of enzymatic breakdown of plant cell walls. In this work, cellulolytic bacteria were isolated from a native and two cultivated forest soil samples. Amplification of glycosyl hydrolases was attempted by using a low stringency-degenerate primer PCR strategy, using total soil DNA and bulk DNA pooled from positive colonies as template. A set of primers was designed based on Acidothermus cellulolyticus genome, by search of conserved domains of glycosyl hydrolases (GH) families of interest. Using this approach, a fragment containing an open reading frame (ORF) with 98% identity to a putative GH43 beta-xylosidase coding gene from Enterobacter cloacae was amplified and cloned. The full protein was expressed in Escherichia coli as N-terminal or C-terminal His-tagged fusions and purified under native conditions. Only N-terminal fusion protein, His-Xyl43, presented beta-xylosidase activity. On pNPX, optimal activity was achieved at pH 6 and 40 °C and Km and Kcat values were 2.92 mM and 1.32 seg(-1), respectively. Activity was also demonstrated on xylobiose (X2), with Km 17.8 mM and Kcat 380 s(-1). These results demonstrated that Xyl43 is a functional beta-xylosidase and it is the first evidence of this activity for Enterobacter sp. Copyright © 2013 Elsevier GmbH. All rights reserved.

  4. Root colonization and growth promotion of sunflower (Helianthus annuus L.) by phosphate solubilizing Enterobacter sp. Fs-11.

    Science.gov (United States)

    Shahid, Muhammad; Hameed, Sohail; Imran, Asma; Ali, Saira; van Elsas, Jan Dirk

    2012-08-01

    An Enterobacter sp. Fs-11 was isolated from sunflower rhizosphere, identified on the basis of 16S rRNA gene sequence analysis (GeneBank accession no. GQ179978) and studied for its root colonization and growth promotion ability in sunflower. Morphologically, it was rod shaped Gram-negative, motile bacterium, producing 4.5 μg mL(-1) indole acetic acid in tryptophan-supplemented medium. It utilized 27 out of 95 substrates in BIOLOG GN2 micro plate system. It was able to convert insoluble tri-calcium phosphate to soluble phosphorus up to 43.5 μg mL(-1) with decrease in pH of the medium up to 4.5 after 10 days incubation at 28 ± 2 °C in the Pikovskaya's broth. High performance liquid chromatography of cell free supernatant showed that Fs-11 produced malic acid and gluconic acid (2.43 and 16.64 μg mL(-1), respectively) in Pikovskaya's broth. Analysis of 900 bp fragment of pyrroloquinoline quinine pqqE gene sequence showed 98 % homology with that of E. cloacae pqqE gene. Confocal laser scanning microscope revealed strong colonization of fluorescently labeled Fs-11 with sunflower roots. Sunflower inoculation with Fs-11 and its rifampicin resistant derivative in sterile sand and natural soil showed that Fs-11 colonized sunflower roots up to 30 days after transplanting in both sterile sand as well as natural soil. Moreover, Fs-11 inoculation resulted in increased plant height, fresh weight, dry weight and total phosphorus contents as compared to un-inoculated plants. The data showed that Enterobacter sp. Fs-11 is an efficient phosphate solubilizing and plant growth promoting rhizobacterium and has great potential to be used as bio-inoculant for sunflower under phosphorus deficient conditions.

  5. Kinetics of biological decolorisation of anthraquinone based Reactive Blue 19 using an isolated strain of Enterobacter sp.F NCIM 5545.

    Science.gov (United States)

    Holkar, Chandrakant R; Pandit, Aniruddha B; Pinjari, Dipak V

    2014-12-01

    In the present study, an attempt was made to evaluate the bacterial decolorisation of Reactive Blue 19 by an Enterobacter sp.F which was isolated from a mixed culture from anaerobic digester for biogas production. Phenotypic characterization and phylogenetic analysis based on DNA sequencing comparisons indicate that Enterobacter sp.F was 99.7% similar to Enterobacter cloacae ATCC13047. The kinetics of Reactive Blue 19 dye decolorisation by bacterium had been estimated. Effects of substrate concentration, oxygen, temperature, pH, glucose and glucose to microbe weight ratio on the rate of decolorisation were investigated to understand key factor that determines the performance of dye decolorisation. The maximum decolorisation efficiency of Reactive Blue 19 was 90% over period of 24 h for optimized parameter. To the best of our knowledge, this research study is the report where Enterobacter sp.F has been reported with about 90% decolorizing ability against anthraquinone based Reactive Blue 19 dye. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Isolation of the opdE gene that encodes for a new hydrolase of Enterobacter sp. capable of degrading organophosphorus pesticides.

    Science.gov (United States)

    Chino-Flores, Concepción; Dantán-González, Edgar; Vázquez-Ramos, Alejandra; Tinoco-Valencia, Raunel; Díaz-Méndez, Rafael; Sánchez-Salinas, Enrique; Castrejón-Godínez, Maria Luisa; Ramos-Quintana, Fernando; Ortiz-Hernández, Maria Laura

    2012-06-01

    Microbial enzymes that can hydrolyze organophosphorus compounds have been isolated, identified and characterized from different microbial species in order to use them in biodegradation of organophosphorus compounds. We isolated a bacterial strain Cons002 from an agricultural soil bacterial consortium, which can hydrolyze methyl-parathion (MP) and other organophosphate pesticides. HPLC analysis showed that strain Cons002 is capable of degrading pesticides MP, parathion and phorate. Pulsed-field gel electrophoresis and 16S rRNA amplification were performed for strain characterization and identification, respectively, showing that the strain Cons002 is related to the genus Enterobacter sp. which has a single chromosome of 4.6 Mb and has no plasmids. Genomic library was constructed from DNA of Enterobacter sp. Cons002. A gene called opdE (Organophosphate Degradation from Enterobacter) consists of 753 bp and encodes a protein of 25 kDa, which was isolated using activity methods. This gene opdE had no similarity to any genes reported to degrade organophosphates. When kanamycin-resistance cassette was placed in the gene opdE, hydrolase activity was suppressed and Enterobacter sp. Cons002 had no growth with MP as a nutrients source.

  7. Enterobacter sp. I-3, a bio-herbicide inhibits gibberellins biosynthetic pathway and regulates abscisic acid and amino acids synthesis to control plant growth.

    Science.gov (United States)

    Radhakrishnan, Ramalingam; Park, Jae-Man; Lee, In-Jung

    2016-12-01

    Very few bacterial species were identified as bio-herbicides for weed control. The present research was focused to elucidate the plant growth retardant properties of Enterobacter sp. I-3 during their interaction by determining the changes in endogenous photosynthetic pigments, plant hormones and amino acids. The two bacterial isolates I-4-5 and I-3 were used to select the superior bacterium for controlling weed seeds (Echinochloa crus-galli L. and Portulaca oleracea L.) germination. The post-inoculation of I-3 (Enterobacter sp. I-3) significantly inhibited the weeds seed germination than their controls. The mechanism of bacterium induced plant growth reduction was identified in lettuce treated with I-3 bacterium and compared their effects with known chemical herbicide, trinexapac-ethyl (TE). The treatment of I-3 and TE showed a significant inhibitory effect on shoot length, leaf number, leaf length, leaf width, shoot weight, root weight and chlorophyll content in lettuce seedlings. The endogenous gibberellins (GAs) and abscisic acid (ABA) analysis showed that Enterobacter sp. I-3 treated plants had lower levels of GAs (GA 12 , GA 19 , GA 20 and GA 8 ) and GAs/ABA ratio and then, the higher level of ABA when compared to their controls. Indeed, the individual amino acids ie., aspartic acid, glutamic acid, glycine, threonine, alanine, serine, leucine, isoleucine and tyrosine were declined in TE and I-3 exposed plants. Our results suggest that the utilization of Enterobacter sp. I-3 inhibits the GAs pathway and amino acids synthesis in weeds to control their growth can be an alternative to chemical herbicides. Copyright © 2016 Elsevier GmbH. All rights reserved.

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

    Science.gov (United States)

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

    2015-11-01

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

  9. Low-temperature-active and salt-tolerant β-mannanase from a newly isolated Enterobacter sp. strain N18.

    Science.gov (United States)

    You, Jia; Liu, Jin-Feng; Yang, Shi-Zhong; Mu, Bo-Zhong

    2016-02-01

    A low-temperature-active and salt-tolerant β-mannanase produced by a novel mannanase-producer, Enterobacter sp. strain N18, was isolated, purified and then evaluated for its potential application as a gel-breaker in relation to viscosity reduction of guar-based hydraulic fracturing fluids used in oil field. The enzyme could lower the viscosity of guar gum solution by more than 95% within 10 min. The purified β-mannanase with molecular mass of 90 kDa displayed high activity in a broad range of pH and temperature: more than 70% of activity was retained in the pH range of 3.0-8.0 with the optimal pH 7.5, about 50% activity at 20°C with the optimal temperature 50°C. Furthermore, the enzyme retained >70% activity in the presence of 0.5-4.0 M NaCl. These properties implied that the enzyme from strain N18 had potential for serving as a gel-breaker for low temperature oil wells and other industrial fields, where chemical gel breakers were inactive due to low temperature. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  10. Cloning, expression and biochemical characterization of a β-carbonic anhydrase from the soil bacterium Enterobacter sp. B13.

    Science.gov (United States)

    Eminoğlu, Ayşenur; Vullo, Daniela; Aşık, Aycan; Çolak, Dilşat Nigar; Supuran, Claudiu T; Çanakçı, Sabriye; Osman Beldüz, Ali

    2016-12-01

    A recombinant carbonic anhydrase (CA, EC 4.2.1.1) from the soil-dwelling bacterium Enterobacter sp. B13 was cloned and purified by Co(2+) affinity chromatography. Bioinformatic analysis showed that the new enzyme (denominated here B13-CA) belongs to the β-class CAs and to possess 95% homology with the ortholog enzyme from Escherichia coli encoded by the can gene, whereas its sequence homology with the other such enzyme from E. coli (encoded by the cynT gene) was of 33%. B13-CA was characterized kinetically as a catalyst for carbon dioxide hydration to bicarbonate and protons. The enzyme shows a significant catalytic activity, with the following kinetic parameters at 20 °C and pH of 8.3: kcat of 4.8 × 10(5) s(-1) and kcat/Km of 5.6 × 10(7) M(-1) × s(-1). This activity was potently inhibited by acetazolamide which showed a KI of 78.9 nM. Although only this compound was investigated for the moment as B13-CA inhibitor, further studies may reveal new classes of inhibitors/activators of this enzyme which may show biomedical or environmental applications, considering the posssible role of this enzyme in CaCO3 biomineralization processes.

  11. Proteomic and biochemical basis for enhanced growth yield of Enterobacter sp. LCR1 on insoluble phosphate medium.

    Science.gov (United States)

    Kumar, Arvind; Rai, Lal Chand

    2015-01-01

    Proteomics and biochemical analyses were used to unravel the basis for higher growth yield of Enterobacter sp. LCR1 on insoluble phosphate medium compared to soluble. Proteomic analysis using 2-DE, MALDI-TOF/MS and LC-MS revealed the involvement of nine proteins. Down-regulation of fructose bisphosphate aldolase with decreased concentrations of glucose-6-phosphate and fructose-6-phosphate indicated diminished glycolysis. However, up-regulation of phosphoglycerate mutase, increase in the activities of 6-phosphogluconate dehydratase, 2-keto-3-deoxy-6-phosphogluconate aldolase and 6-phosphogluconate dehydrogenase suggested induction of Entner-Doudoroff and pentose phosphate pathways. These pathways generate sufficient energy from gluconic acid, which is also used for biosynthesis as indicated by up-regulation of elongation factor Tu, elongation factor G and protein disulfide isomerase. Increased reactive oxygen species (ROS) formation resulting from organic acid oxidation leads to overexpressed manganese superoxide dismutase and increased activities of catalase and ascorbate peroxidase. Thus the organism uses gluconate instead of glucose for energy, while alleviating extra ROS formation by oxidative defense enzymes. Copyright © 2014 Elsevier GmbH. All rights reserved.

  12. Sulfonamide inhibition studies of the β-carbonic anhydrase from the newly discovered bacterium Enterobacter sp. B13.

    Science.gov (United States)

    Eminoğlu, Ayşenur; Vullo, Daniela; Aşık, Aycan; Çolak, Dilşat Nigar; Çanakçı, Sabriye; Beldüz, Ali Osman; Supuran, Claudiu T

    2016-04-01

    The genome of the newly identified bacterium Enterobacter sp. B13 encodes for a β-class carbonic anhydrases (CAs, EC 4.2.1.1), EspCA. This enzyme was recently cloned, and characterized kinetically by this group (J. Enzyme Inhib. Med. Chem. 2016, 31). Here we report an inhibition study with sulfonamides and sulfamates of this enzyme. The best EspCA inhibitors were some sulfanylated sulfonamides with elongated molecules, metanilamide, 4-aminoalkyl-benzenesulfonamides, acetazolamide, and deacetylated methazolamide (KIs in the range of 58.7-96.5nM). Clinically used agents such as methazolamide, ethoxzolamide, dorzolamide, brinzolamide, benzolamide, zonisamide, sulthiame, sulpiride, topiramate and valdecoxib were slightly less effective inhibitors (KIs in the range of 103-138nM). Saccharin, celecoxib, dichlorophenamide and many simple benzenesulfonamides were even less effective as EspCA inhibitors, with KIs in the range of 384-938nM. Identification of effective inhibitors of this bacterial enzyme may lead to pharmacological tools useful for understanding the physiological role(s) of the β-class CAs in bacterial pathogenicity/virulence. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Complete genome sequence of Enterobacter sp. IIT-BT 08: A potential microbial strain for high rate hydrogen production.

    Science.gov (United States)

    Khanna, Namita; Ghosh, Ananta Kumar; Huntemann, Marcel; Deshpande, Shweta; Han, James; Chen, Amy; Kyrpides, Nikos; Mavrommatis, Kostas; Szeto, Ernest; Markowitz, Victor; Ivanova, Natalia; Pagani, Ioanna; Pati, Amrita; Pitluck, Sam; Nolan, Matt; Woyke, Tanja; Teshima, Hazuki; Chertkov, Olga; Daligault, Hajnalka; Davenport, Karen; Gu, Wei; Munk, Christine; Zhang, Xiaojing; Bruce, David; Detter, Chris; Xu, Yan; Quintana, Beverly; Reitenga, Krista; Kunde, Yulia; Green, Lance; Erkkila, Tracy; Han, Cliff; Brambilla, Evelyne-Marie; Lang, Elke; Klenk, Hans-Peter; Goodwin, Lynne; Chain, Patrick; Das, Debabrata

    2013-12-20

    Enterobacter sp. IIT-BT 08 belongs to Phylum: Proteobacteria, Class: Gammaproteobacteria, Order: Enterobacteriales, Family: Enterobacteriaceae. The organism was isolated from the leaves of a local plant near the Kharagpur railway station, Kharagpur, West Bengal, India. It has been extensively studied for fermentative hydrogen production because of its high hydrogen yield. For further enhancement of hydrogen production by strain development, complete genome sequence analysis was carried out. Sequence analysis revealed that the genome was linear, 4.67 Mbp long and had a GC content of 56.01%. The genome properties encode 4,393 protein-coding and 179 RNA genes. Additionally, a putative pathway of hydrogen production was suggested based on the presence of formate hydrogen lyase complex and other related genes identified in the genome. Thus, in the present study we describe the specific properties of the organism and the generation, annotation and analysis of its genome sequence as well as discuss the putative pathway of hydrogen production by this organism.

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

    Directory of Open Access Journals (Sweden)

    Wen Gu

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

  15. Complete Genome Sequence Analysis of Enterobacter sp. SA187, a Plant Multi-Stress Tolerance Promoting Endophytic Bacterium

    KAUST Repository

    Andres-Barrao, Cristina

    2017-10-20

    Enterobacter sp. SA187 is an endophytic bacterium that has been isolated from root nodules of the indigenous desert plant Indigofera argentea. SA187 could survive in the rhizosphere as well as in association with different plant species, and was able to provide abiotic stress tolerance to Arabidopsis thaliana. The genome sequence of SA187 was obtained by using Pacific BioScience (PacBio) single-molecule sequencing technology, with average coverage of 275X. The genome of SA187 consists of one single 4,429,597 bp chromosome, with an average 56% GC content and 4,347 predicted protein coding DNA sequences (CDS), 153 ncRNA, 7 rRNA, and 84 tRNA. Functional analysis of the SA187 genome revealed a large number of genes involved in uptake and exchange of nutrients, chemotaxis, mobilization and plant colonization. A high number of genes were also found to be involved in survival, defense against oxidative stress and production of antimicrobial compounds and toxins. Moreover, different metabolic pathways were identified that potentially contribute to plant growth promotion. The information encoded in the genome of SA187 reveals the characteristics of a dualistic lifestyle of a bacterium that can adapt to different environments and promote the growth of plants. This information provides a better understanding of the mechanisms involved in plant-microbe interaction and could be further exploited to develop SA187 as a biological agent to improve agricultural practices in marginal and arid lands.

  16. Complete Genome Sequence Analysis of Enterobacter sp. SA187, a Plant Multi-Stress Tolerance Promoting Endophytic Bacterium

    KAUST Repository

    Andres-Barrao, Cristina; Lafi, Feras Fawzi; Alam, Intikhab; Zé licourt, Axel de; Eida, Abdul Aziz; Bokhari, Ameerah; Alzubaidy, Hanin S.; Bajic, Vladimir B.; Hirt, Heribert; Saad, Maged

    2017-01-01

    Enterobacter sp. SA187 is an endophytic bacterium that has been isolated from root nodules of the indigenous desert plant Indigofera argentea. SA187 could survive in the rhizosphere as well as in association with different plant species, and was able to provide abiotic stress tolerance to Arabidopsis thaliana. The genome sequence of SA187 was obtained by using Pacific BioScience (PacBio) single-molecule sequencing technology, with average coverage of 275X. The genome of SA187 consists of one single 4,429,597 bp chromosome, with an average 56% GC content and 4,347 predicted protein coding DNA sequences (CDS), 153 ncRNA, 7 rRNA, and 84 tRNA. Functional analysis of the SA187 genome revealed a large number of genes involved in uptake and exchange of nutrients, chemotaxis, mobilization and plant colonization. A high number of genes were also found to be involved in survival, defense against oxidative stress and production of antimicrobial compounds and toxins. Moreover, different metabolic pathways were identified that potentially contribute to plant growth promotion. The information encoded in the genome of SA187 reveals the characteristics of a dualistic lifestyle of a bacterium that can adapt to different environments and promote the growth of plants. This information provides a better understanding of the mechanisms involved in plant-microbe interaction and could be further exploited to develop SA187 as a biological agent to improve agricultural practices in marginal and arid lands.

  17. Ethylene induced plant stress tolerance by Enterobacter sp. SA187 is mediated by 2-keto-4-methylthiobutyric acid production.

    Directory of Open Access Journals (Sweden)

    Axel de Zélicourt

    2018-03-01

    Full Text Available Several plant species require microbial associations for survival under different biotic and abiotic stresses. In this study, we show that Enterobacter sp. SA187, a desert plant endophytic bacterium, enhances yield of the crop plant alfalfa under field conditions as well as growth of the model plant Arabidopsis thaliana in vitro, revealing a high potential of SA187 as a biological solution for improving crop production. Studying the SA187 interaction with Arabidopsis, we uncovered a number of mechanisms related to the beneficial association of SA187 with plants. SA187 colonizes both the surface and inner tissues of Arabidopsis roots and shoots. SA187 induces salt stress tolerance by production of bacterial 2-keto-4-methylthiobutyric acid (KMBA, known to be converted into ethylene. By transcriptomic, genetic and pharmacological analyses, we show that the ethylene signaling pathway, but not plant ethylene production, is required for KMBA-induced plant salt stress tolerance. These results reveal a novel molecular communication process during the beneficial microbe-induced plant stress tolerance.

  18. Characterization of a heavy metal translocating P-type ATPase gene from an environmental heavy metal resistance Enterobacter sp. isolate.

    Science.gov (United States)

    Chien, Chih-Ching; Huang, Chia-Hsuan; Lin, Yi-Wei

    2013-03-01

    Heavy metals are common contaminants found in polluted areas. We have identified a heavy metal translocating P-type ATPase gene (hmtp) via fosmid library and in vitro transposon mutagenesis from an Enterobacter sp. isolate. This gene is believed to participate in the bacterium's heavy metal resistance traits. The complete gene was identified, cloned, and expressed in a suitable Escherichia coli host cell. E. coli W3110, RW3110 (zntA::Km), GG48 (ΔzitB::Cm zntA::Km), and GG51 (ΔzitB::Cm) were used to study the possible effects of this gene for heavy metal (cadmium and zinc in particular) resistance. Among the E. coli strains tested, RW3110 and GG48 showed more sensitivity to cadmium and zinc compared to the wild-type E. coli W3110 and strain GG51. Therefore, strains RW3110 and GG48 were chosen for the reference hosts for further evaluation of the gene's effect. The results showed that expression of this heavy metal translocating P-type ATPase gene could increase the ability for zinc and cadmium resistance in the tested microorganisms.

  19. The waaL gene mutation compromised the inhabitation of Enterobacter sp. Ag1 in the mosquito gut environment.

    Science.gov (United States)

    Pei, Dong; Jiang, Jinjin; Yu, Wanqin; Kukutla, Phanidhar; Uentillie, Alejandro; Xu, Jiannong

    2015-08-27

    The mosquito gut harbors a variety of bacteria that are dynamically associated with mosquitoes in various contexts. However, little is known about bacterial factors that affect bacterial inhabitation in the gut microbial community. Enterobacter sp. Ag1 is a predominant Gram negative bacterium in the mosquito midgut. In a mutant library that was generated using transposon Tn5-mediated mutagenesis, a mutant was identified, in which the gene waaL was disrupted by the Tn5 insertion. The waaL encodes O antigen ligase, which is required for the attachment of O antigen to the outer core oligosaccharide of the lipopolysaccharide (LPS). The waaL(-) mutation caused the O antigen repeat missing in the LPS. The normal LPS structure was restored when the mutant was complemented with a plasmid containing waaL gene. The waaL(-) mutation did not affect bacterial proliferation in LB culture, the mutant cells grew at a rate the same as the wildtype (wt) cells. However, when waaL(-) strain were co-cultured with the wt strain or complemented strain, the mutant cells proliferated with a slower rate, indicating that the mutants were less competitive than wt cells in a community setting. Similarly, in a co-feeding assay, when fluorescently tagged wt strain and waaL(-) strain were orally co-introduced into the gut of Anopheles stephensi mosquitoes, the mutant cells were less prevalent in both sugar-fed and blood-fed guts. The data suggest that the mutation compromised the bacterial inhabitation in the gut community. Besides, the mutant was more sensitive to oxidative stress, demonstrated by lower survival rate upon exposure to 20 mM H₂O₂. Lack of the O antigen structure in LPS of Enterobacter compromised the effective growth in co-culture and co-feeding assays. In addition, O-antigen was involved in protection against oxidative stress. The findings suggest that intact LPS is crucial for the bacteria to steadily stay in the gut microbial community.

  20. Outbreak of a novel Enterobacter sp. carrying blaCTX-M-15 in a neonatal unit of a tertiary care hospital in Tanzania.

    Science.gov (United States)

    Mshana, Stephen E; Gerwing, Lisa; Minde, Mercy; Hain, Torsten; Domann, Eugen; Lyamuya, Eligius; Chakraborty, Trinad; Imirzalioglu, Can

    2011-09-01

    Enterobacter hormaechei and Cronobacter sakazakii are amongst the most important causes of outbreaks of neonatal sepsis associated with powdered milk. In this study, we report for the first time an outbreak of a novel Enterobacter sp. harbouring bla(CTX-M-15) in a neonatal unit in Tanzania. Seventeen Gram-negative enteric isolates from neonatal blood cultures were studied. Antibiotic susceptibility was assessed by disc diffusion testing, and the presence of the bla(CTX-M-15) gene was established by polymerase chain reaction (PCR) and sequencing. Isolates were typed by pulsed-field gel electrophoresis (PFGE). Identification by biochemical profiling was followed by nucleotide sequencing of 16S ribosomal DNA (rDNA), rpoB and hsp60 alleles. Environmental sampling was done and control measures were established. Isolates were initially misidentified based on their fermentation characteristics and agglutination as Salmonella enterica serotype Paratyphi. All isolates were resistant to multiple antibiotics, except for ciprofloxacin and carbapenems, and were found to harbour bla(CTX-M-15) on a 291-kb narrow-range plasmid. PFGE analysis indicated the clonal outbreak of a single strain, infecting 17 neonates with a case fatality rate of 35%. The same strain was isolated from a milk bucket. Phylogenetic analysis using 16S rDNA, rpoB and hsp60 sequences permitted no definitive identification, clustering the strains in the Enterobacter cloacae complex with similarities of 92-98.8%. The data describe an outbreak of a novel bla(CTX-M-15)-positive, multiresistant Enterobacter strain in an African neonatal unit that can easily be misidentified taxonomically. These data highlight the need for constant surveillance of bacteria harbouring extended-spectrum β-lactamases as well as improvements in hygiene measures in developing countries. Copyright © 2011 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

  1. Molecular Characterization of the Plant Growth Promoting Bacterium Enterobacter sp. SA187 upon Contact with Arabidopsis thaliana

    KAUST Repository

    Alsharif, Wiam

    2018-05-01

    Salt stress is a severe environmental challenge in agriculture, limiting the quality and productivity of the crops around the globe. Plant growth promoting rhizobacteria (PGPR) is proposed as a friendly solution to overcome those challenges. The desert plant endophytic bacterium, Enterobacter sp. SA187 has shown plant growth promotion and salt stress tolerance beneficial effect on the model plant Arabidopsis thaliana in vitro as well as under the field conditions on different crops. SA187 has a distinguished morphology of yellow colonies (SA187Y) that could be due to carotenoid biosynthesis. However, the bacteria tend to lose the yellow color upon incubation with the plants and the colonies turn to white (SA187W). In comparison to SA187Y, SA187W shows 50% reduction on the beneficial impact on A. thaliana fresh and dry weight of root and shoot system. By counting the CFU/plant, we showed that SA187Y and SA187W both have similar colonization rate in both shoots and roots. Under non-salt conditions, optimal bacterial colonization was observed on day 8 after inocubation, however, under the salt stress condition, the optimal colonization was observed at day 4. Moreover, during the time period of the incubation of the SA187Y with the plants, there was a consistent noticeable loss of the yellow color of the colonies. This change in color is only observed eight days after transfer and the number of white colonies increases with the increase of the incubation time. In addition, SA187W was GFP-tagged by Tn7 transposon system and visualized by confocal laser scanning microscopy. The SA187W-GFP colonies have shown a similar colonization pattern as SA187Y-GFP, bacteria were colonizing the differentiation zone and cell elongation zone in the roots. Finally, the gene expression of the carotenoid biosynthesis pathways genes in SA187Y showed an overall higher gene expression compared to SA187W. In conclusion, the color loss seems to affect the beneficial impact of the bacteria on

  2. Exploitation of the Medfly Gut Microbiota for the Enhancement of Sterile Insect Technique: Use of Enterobacter sp. in Larval Diet-Based Probiotic Applications.

    Directory of Open Access Journals (Sweden)

    Antonios A Augustinos

    Full Text Available The Mediterranean fruit fly (medfly, Ceratitis capitata, is a pest of worldwide substantial economic importance, as well as a Tephritidae model for sterile insect technique (SIT applications. The latter is partially due to the development and utilization of genetic sexing strains (GSS for this species, such as the Vienna 8 strain, which is currently used in mass rearing facilities worldwide. Improving the performance of such a strain both in mass rearing facilities and in the field could significantly enhance the efficacy of SIT and reduce operational costs. Recent studies have suggested that the manipulation of gut symbionts can have a significant positive effect on the overall fitness of insect strains. We used culture-based approaches to isolate and characterize gut-associated bacterial species of the Vienna 8 strain under mass rearing conditions. We also exploited one of the isolated bacterial species, Enterobacter sp., as dietary supplement (probiotic to the larval diet, and we assessed its effects on fitness parameters under the standard operating procedures used in SIT operational programs. Probiotic application of Enterobacter sp. resulted in improvement of both pupal and adult productivity, as well as reduced rearing duration, particularly for males, without affecting pupal weight, sex ratio, male mating competitiveness, flight ability and longevity under starvation.

  3. Exploitation of the Medfly Gut Microbiota for the Enhancement of Sterile Insect Technique: Use of Enterobacter sp. in Larval Diet-Based Probiotic Applications

    Science.gov (United States)

    Papadopoulos, Nikos T.; Abd-Alla, Adly M. M.; Cáceres, Carlos; Bourtzis, Kostas

    2015-01-01

    The Mediterranean fruit fly (medfly), Ceratitis capitata, is a pest of worldwide substantial economic importance, as well as a Tephritidae model for sterile insect technique (SIT) applications. The latter is partially due to the development and utilization of genetic sexing strains (GSS) for this species, such as the Vienna 8 strain, which is currently used in mass rearing facilities worldwide. Improving the performance of such a strain both in mass rearing facilities and in the field could significantly enhance the efficacy of SIT and reduce operational costs. Recent studies have suggested that the manipulation of gut symbionts can have a significant positive effect on the overall fitness of insect strains. We used culture-based approaches to isolate and characterize gut-associated bacterial species of the Vienna 8 strain under mass rearing conditions. We also exploited one of the isolated bacterial species, Enterobacter sp., as dietary supplement (probiotic) to the larval diet, and we assessed its effects on fitness parameters under the standard operating procedures used in SIT operational programs. Probiotic application of Enterobacter sp. resulted in improvement of both pupal and adult productivity, as well as reduced rearing duration, particularly for males, without affecting pupal weight, sex ratio, male mating competitiveness, flight ability and longevity under starvation. PMID:26325068

  4. Characterization of Fe (III)-reducing enrichment culture and isolation of Fe (III)-reducing bacterium Enterobacter sp. L6 from marine sediment.

    Science.gov (United States)

    Liu, Hongyan; Wang, Hongyu

    2016-07-01

    To enrich the Fe (III)-reducing bacteria, sludge from marine sediment was inoculated into the medium using Fe (OH)3 as the sole electron acceptor. Efficiency of Fe (III) reduction and composition of Fe (III)-reducing enrichment culture were analyzed. The results indicated that the Fe (III)-reducing enrichment culture with the dominant bacteria relating to Clostridium and Enterobacter sp. had high Fe (III) reduction of (2.73 ± 0.13) mmol/L-Fe (II). A new Fe (III)-reducing bacterium was isolated from the Fe (III)-reducing enrichment culture and identified as Enterobacter sp. L6 by 16S rRNA gene sequence analysis. The Fe (III)-reducing ability of strain L6 under different culture conditions was investigated. The results indicated that strain L6 had high Fe (III)-reducing activity using glucose and pyruvate as carbon sources. Strain L6 could reduce Fe (III) at the range of NaCl concentrations tested and had the highest Fe (III) reduction of (4.63 ± 0.27) mmol/L Fe (II) at the NaCl concentration of 4 g/L. This strain L6 could reduce Fe (III) with unique properties in adaptability to salt variation, which indicated that it can be used as a model organism to study Fe (III)-reducing activity isolated from marine environment. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  5. Alleviation of salt stress by enterobacter sp. EJ01 in tomato and Arabidopsis is accompanied by up-regulation of conserved salinity responsive factors in plants.

    Science.gov (United States)

    Kim, Kangmin; Jang, Ye-Jin; Lee, Sang-Myeong; Oh, Byung-Taek; Chae, Jong-Chan; Lee, Kui-Jae

    2014-02-01

    Microbiota in the niches of the rhizosphere zones can affect plant growth and responses to environmental stress conditions via mutualistic interactions with host plants. Specifically, some beneficial bacteria, collectively referred to as Plant Growth Promoting Rhizobacteria (PGPRs), increase plant biomass and innate immunity potential. Here, we report that Enterobacter sp. EJ01, a bacterium isolated from sea china pink (Dianthus japonicus thunb) in reclaimed land of Gyehwa-do in Korea, improved the vegetative growth and alleviated salt stress in tomato and Arabidopsis. EJ01 was capable of producing 1-aminocy-clopropane-1-carboxylate (ACC) deaminase and also exhibited indole-3-acetic acid (IAA) production. The isolate EJ01 conferred increases in fresh weight, dry weight, and plant height of tomato and Arabidopsis under both normal and high salinity conditions. At the molecular level, short-term treatment with EJ01 increased the expression of salt stress responsive genes such as DREB2b, RD29A, RD29B, and RAB18 in Arabidopsis. The expression of proline biosynthetic genes (i.e. P5CS1 and P5CS2) and of genes related to priming processes (i.e. MPK3 and MPK6) were also up-regulated. In addition, reactive oxygen species scavenging activities were enhanced in tomatoes treated with EJ01 in stressed conditions. GFP-tagged EJ01 displayed colonization in the rhizosphere and endosphere in the roots of Arabidopsis. In conclusion, the newly isolated Enterobacter sp. EJ01 is a likely PGPR and alleviates salt stress in host plants through multiple mechanisms, including the rapid up-regulation of conserved plant salt stress responsive signaling pathways.

  6. Alleviation of Salt Stress by Enterobacter sp. EJ01 in Tomato and Arabidopsis Is Accompanied by Up-Regulation of Conserved Salinity Responsive Factors in Plants

    Science.gov (United States)

    Kim, Kangmin; Jang, Ye-Jin; Lee, Sang-Myeong; Oh, Byung-Taek; Chae, Jong-Chan; Lee, Kui-Jae

    2014-01-01

    Microbiota in the niches of the rhizosphere zones can affect plant growth and responses to environmental stress conditions via mutualistic interactions with host plants. Specifically, some beneficial bacteria, collectively referred to as Plant Growth Promoting Rhizobacteria (PGPRs), increase plant biomass and innate immunity potential. Here, we report that Enterobacter sp. EJ01, a bacterium isolated from sea china pink (Dianthus japonicus thunb) in reclaimed land of Gyehwa-do in Korea, improved the vegetative growth and alleviated salt stress in tomato and Arabidopsis. EJ01 was capable of producing 1-aminocy-clopropane-1-carboxylate (ACC) deaminase and also exhibited indole-3-acetic acid (IAA) production. The isolate EJ01 conferred increases in fresh weight, dry weight, and plant height of tomato and Arabidopsis under both normal and high salinity conditions. At the molecular level, short-term treatment with EJ01 increased the expression of salt stress responsive genes such as DREB2b, RD29A, RD29B, and RAB18 in Arabidopsis. The expression of proline biosynthetic genes (i.e. P5CS1 and P5CS2) and of genes related to priming processes (i.e. MPK3 and MPK6) were also up-regulated. In addition, reactive oxygen species scavenging activities were enhanced in tomatoes treated with EJ01 in stressed conditions. GFP-tagged EJ01 displayed colonization in the rhizosphere and endosphere in the roots of Arabidopsis. In conclusion, the newly isolated Enterobacter sp. EJ01 is a likely PGPR and alleviates salt stress in host plants through multiple mechanisms, including the rapid up-regulation of conserved plant salt stress responsive signaling pathways. PMID:24598995

  7. Effects of Cd, Pb, Zn, Cu-resistant endophytic Enterobacter sr CBSB1 and Rhodotorula sp. CBSB79 on the growth and phytoextraction of Brassica plants in multimetal contaminated soils.

    Science.gov (United States)

    Wang, Wenfeng; Deng, Zujun; Tan, Hongming; Cao, Lixiang

    2013-01-01

    To survey the effects of endophytic Enterobacter sp. CBSB1 and Rhodotorula sp. CBSB79 resistant to Cd2+, Pb2+, Zn2+, and Cu2+ on the growth and phytoextraction of Brassica, the endophytes were isolated by surface- sterilized methods and characterized. The CBSB1 significantly increased 44.2% of the dry weight of Brassica napus in the multimetal contaminated soil (P Rhodotorula sp CBSB79 showed higher potentials to improve extraction efficacy of Cd, Pb, Zn, and Cu by Brassica seedlings in the field.

  8. Increased growth and root Cu accumulation of Sorghum sudanense by endophytic Enterobacter sp. K3-2: Implications for Sorghum sudanense biomass production and phytostabilization.

    Science.gov (United States)

    Li, Ya; Wang, Qi; Wang, Lu; He, Lin-Yan; Sheng, Xia-Fang

    2016-02-01

    Endophytic bacterial strain K3-2 was isolated from the roots of Sorghum sudanense (an bioenergy plant) grown in a Cu mine wasteland soils and characterized. Strain K3-2 was identified as Enterobacter sp. based on 16S rRNA gene sequence analysis. Strain K3-2 exhibited Cu resistance and produced 1-aminocyclopropane-1-carboxylate (ACC) deaminase, indole-3-acetic acid (IAA), siderophores, and arginine decarboxylase. Pot experiments showed that strain K3-2 significantly increased the dry weight and root Cu accumulation of Sorghum sudanense grown in the Cu mine wasteland soils. Furthermore, increase in total Cu uptake (ranging from 49% to 95%) of the bacterial inoculated-Sorghum sudanense was observed compared to the control. Notably, most of Cu (83-86%) was accumulated in the roots of Sorghum sudanense. Furthermore, inoculation with strain K3-2 was found to significantly increase Cu bioconcentration factors and the proportions of IAA- and siderophore-producing bacteria in the root interiors and rhizosphere soils of Sorghum sudanense compared with the control. Significant decrease in the available Cu content was also observed in the rhizosphere soils of the bacterial-inoculated Sorghum sudanense. The results suggest that the endophytic bacterial strain K3-2 may be exploited for promoting Sorghum sudanense biomass production and Cu phytostabilization in the Cu mining wasteland soils. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Production, Characterization, and Flocculation Mechanism of Cation Independent, pH Tolerant, and Thermally Stable Bioflocculant from Enterobacter sp. ETH-2

    Science.gov (United States)

    Tang, Wei; Song, Liyan; Li, Dou; Qiao, Jing; Zhao, Tiantao; Zhao, Heping

    2014-01-01

    Synthetic high polymer flocculants, frequently utilized for flocculating efficiency and low cost, recently have been discovered as producing increased risk to human health and the environment. Development of a more efficient and environmentally sound alternative flocculant agent is investigated in this paper. Bioflocculants are produced by microorganisms and may exhibit a high rate of flocculation activity. The bioflocculant ETH-2, with high flocculating activity (2849 mg Kaolin particle/mg ETH-2), produced by strain Enterobacter sp. isolated from activated sludge, was systematically investigated with regard to its production, characterization, and flocculation mechanism. Analyses of microscopic observation, zeta potential and ETH-2 structure demonstrates the bridging mechanism, as opposed to charge neutralization, was responsible for flocculation of the ETH-2. ETH-2 retains high molecular weight (603 to 1820 kDa) and multi-functional groups (hydroxyl, amide and carboxyl) that contributed to flocculation. Polysaccharides mainly composed of mannose, glucose, and galactose, with a molar ratio of 1∶2.9∶9.8 were identified as the active constituents in bioflocculant. The structure of the long backbone with active sites of polysaccharides was determined as a primary basis for the high flocculation activity. Bioflocculant ETH-2 is cation independent, pH tolerant, and thermally stable, suggesting a potential fit for industrial application. PMID:25485629

  10. Ethylene induced plant stress tolerance by Enterobacter sp. SA187 is mediated by 2‐keto‐4‐methylthiobutyric acid production

    KAUST Repository

    Zélicourt, Axel de

    2018-03-19

    Several plant species require microbial associations for survival under different biotic and abiotic stresses. In this study, we show that Enterobacter sp. SA187, a desert plant endophytic bacterium, enhances yield of the crop plant alfalfa under field conditions as well as growth of the model plant Arabidopsis thaliana in vitro, revealing a high potential of SA187 as a biological solution for improving crop production. Studying the SA187 interaction with Arabidopsis, we uncovered a number of mechanisms related to the beneficial association of SA187 with plants. SA187 colonizes both the surface and inner tissues of Arabidopsis roots and shoots. SA187 induces salt stress tolerance by production of bacterial 2-keto-4-methylthiobutyric acid (KMBA), known to be converted into ethylene. By transcriptomic, genetic and pharmacological analyses, we show that the ethylene signaling pathway, but not plant ethylene production, is required for KMBA-induced plant salt stress tolerance. These results reveal a novel molecular communication process during the beneficial microbe-induced plant stress tolerance.

  11. Ethylene induced plant stress tolerance by Enterobacter sp. SA187 is mediated by 2‐keto‐4‐methylthiobutyric acid production

    Science.gov (United States)

    Xie, Yakun; Rolli, Eleonora; Guerard, Florence; Colcombet, Jean; Benhamed, Moussa; Depaepe, Thomas

    2018-01-01

    Several plant species require microbial associations for survival under different biotic and abiotic stresses. In this study, we show that Enterobacter sp. SA187, a desert plant endophytic bacterium, enhances yield of the crop plant alfalfa under field conditions as well as growth of the model plant Arabidopsis thaliana in vitro, revealing a high potential of SA187 as a biological solution for improving crop production. Studying the SA187 interaction with Arabidopsis, we uncovered a number of mechanisms related to the beneficial association of SA187 with plants. SA187 colonizes both the surface and inner tissues of Arabidopsis roots and shoots. SA187 induces salt stress tolerance by production of bacterial 2-keto-4-methylthiobutyric acid (KMBA), known to be converted into ethylene. By transcriptomic, genetic and pharmacological analyses, we show that the ethylene signaling pathway, but not plant ethylene production, is required for KMBA-induced plant salt stress tolerance. These results reveal a novel molecular communication process during the beneficial microbe-induced plant stress tolerance. PMID:29554117

  12. Production, characterization, and flocculation mechanism of cation independent, pH tolerant, and thermally stable bioflocculant from Enterobacter sp. ETH-2.

    Directory of Open Access Journals (Sweden)

    Wei Tang

    Full Text Available Synthetic high polymer flocculants, frequently utilized for flocculating efficiency and low cost, recently have been discovered as producing increased risk to human health and the environment. Development of a more efficient and environmentally sound alternative flocculant agent is investigated in this paper. Bioflocculants are produced by microorganisms and may exhibit a high rate of flocculation activity. The bioflocculant ETH-2, with high flocculating activity (2849 mg Kaolin particle/mg ETH-2, produced by strain Enterobacter sp. isolated from activated sludge, was systematically investigated with regard to its production, characterization, and flocculation mechanism. Analyses of microscopic observation, zeta potential and ETH-2 structure demonstrates the bridging mechanism, as opposed to charge neutralization, was responsible for flocculation of the ETH-2. ETH-2 retains high molecular weight (603 to 1820 kDa and multi-functional groups (hydroxyl, amide and carboxyl that contributed to flocculation. Polysaccharides mainly composed of mannose, glucose, and galactose, with a molar ratio of 1:2.9:9.8 were identified as the active constituents in bioflocculant. The structure of the long backbone with active sites of polysaccharides was determined as a primary basis for the high flocculation activity. Bioflocculant ETH-2 is cation independent, pH tolerant, and thermally stable, suggesting a potential fit for industrial application.

  13. Entericidin is required for a probiotic treatment (Enterobacter sp. strain C6-6) to protect trout from cold-water disease challenge.

    Science.gov (United States)

    Schubiger, Carla B; Orfe, Lisa H; Sudheesh, Ponnerassery S; Cain, Kenneth D; Shah, Devendra H; Call, Douglas R

    2015-01-01

    Flavobacterium psychrophilum causes bacterial cold-water disease in multiple fish species, including salmonids. An autochthonous Enterobacter strain (C6-6) inhibits the in vitro growth of F. psychrophilum, and when ingested as a putative probiotic, it provides protection against injection challenge with F. psychrophilum in rainbow trout. In this study, low-molecular-mass (≤3 kDa) fractions from both Enterobacter C6-6 and Escherichia coli K-12 culture supernatants inhibited the growth of F. psychrophilum. The ≤3-kDa fraction from Enterobacter C6-6 was analyzed by SDS-PAGE, and subsequent tandem mass spectroscopy identified EcnB, which is a small membrane lipoprotein that is a putative pore-forming toxin. Agar plate diffusion assays demonstrated that ecnAB knockout strains of both Enterobacter C6-6 and E. coli K-12 no longer inhibited F. psychrophilum (P ) and the wild-type strain (C6-6) were added to the fish diet every day for 38 days. On day 11, the fish were challenged by injection with a virulent strain of F. psychrophilum (CSF 259-93). Fish that were fed C6-6 had significantly longer survival than fish fed the ecnAB knockout strain (P Enterobacter C6-6, and it may present new opportunities for therapeutic and prophylactic treatments against similarly susceptible pathogens. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  14. Target-oriented discovery of a new esterase-producing strain Enterobacter sp. ECU1107 for whole cell-catalyzed production of (2S,3R)-3-phenylglycidate as a chiral synthon of Taxol.

    Science.gov (United States)

    Zhou, Dong-Jie; Pan, Jiang; Yu, Hui-Lei; Zheng, Gao-Wei; Xu, Jian-He

    2013-07-01

    A new strain, Enterobacter sp. ECU1107, was identified among over 200 soil isolates using a two-step screening strategy for the enantioselective synthesis of (2S,3R)-3-phenylglycidate methyl ester (PGM), a key intermediate for production of a potent anticancer drug Taxol®. An organic-aqueous biphasic system was employed to reduce spontaneous hydrolysis of the substrate PGM and isooctane was found to be the most suitable organic solvent. The temperature and pH optima of the whole cell-mediated bioreaction were 40 °C and 6.0, respectively. Under these reaction conditions, the enantiomeric excess (ee(s)) of (2S,3R)-PGM recovered was greater than 99 % at approximately 50 % conversion. The total substrate loading in batch reaction could reach 600 mM. By using whole cells of Enterobacter sp. ECU1107, (2S,3R)-PGM was successfully prepared in decagram scale in a 1.0-l mechanically stirred reactor, affording the chiral epoxy ester in >99 % ee s and 43.5 % molar yield based on the initial load of racemic substrate.

  15. Medfly Gut Microbiota and Enhancement of the Sterile Insect Technique: Similarities and Differences of Klebsiella oxytoca and Enterobacter sp. AA26 Probiotics during the Larval and Adult Stages of the VIENNA 8D53+ Genetic Sexing Strain

    Directory of Open Access Journals (Sweden)

    Georgios A. Kyritsis

    2017-10-01

    Full Text Available The Mediterranean fruit fly, Ceratitis capitata, is a major agricultural pest worldwide. The development of genetic sexing strains (GSSs for this species that allows male-only sterile insects releases has boosted the effectiveness of the environmental friendly pest control method known as the sterile insect technique. The last generation of these strains, the VIENNA 7 and VIENNA 8, are currently used in all mass rearing facilities worldwide and are considered as models for such pest control applications. The sterile insect technique depends on the rearing of sufficient numbers of adequate “biological quality” laboratory flies to be released in the field. Currently, there is an increasing amount of studies focusing on the characterization of the symbiotic communities and development of probiotic diets. In our study, two bacterial isolates, an Enterobacter sp. (strain AA26 and a Klebsiella oxytoca strain, were used as probiotics in larval and adult diet. These strains have been shown to be beneficial, affecting several aspects related to the rearing efficiency and biological quality of the medfly VIENNA 8D53+ GSS. Our results demonstrate the effect of K. oxytoca on the developmental duration of the immature stages and, to some extent, on flight ability. On the other hand, our study does not support the presence of any beneficial effect of (a K. oxytoca on pupal and adult recovery and adults’ survival under stress conditions when provided as a larval diet supplement and (b K. oxytoca and Enterobacter sp. AA26 on mating competitiveness when provided as adult diet supplements. Possible explanations for inconsistencies with previous studies and the need for universalizing protocols are discussed. Our findings, combined with previous studies can support the sterile insect technique, through the improvement of different aspects of mass rearing and biological properties of laboratory reared insect pests.

  16. Isolation and characterization of xanthan-degrading Enterobacter sp. nov. LB37 for reducing the viscosity of xanthan in petroleum industry.

    Science.gov (United States)

    Chen, Xiaoyi; Wang, Mi; Yang, Fan; Tang, Wenzhu; Li, Xianzhen

    2014-05-01

    A Gram-negative, straight rod and facultative anaerobic bacterium was isolated from soil sample. It exhibits the phenotypic characteristics consistent with its classification in the genus Enterobacter. The isolate ferment glucose to acid and gas. Arginine dihydrolase, ornithin decarboxylase and gelatinase but not deoxyribonuclease was produced by this isolate. There was no hydrogen sulfide production. On the basis of the phenotypic data, together with phylogenetic analysis based on 16S rDNA gene sequences, this strain should represent a novel species of the genus Enterobacter and was designated as LB37. The strain LB37 could degrade xanthan molecules resulting in the rapid decrease of the viscosity of xanthan solution used in oil drilling process. Endoxanthanase activity was also detected in the culture supernatant. To our knowledge, it is the first report on the microbes being involved in the xanthan degradation for oil industry. The isolate LB37 would be useful for potential application in enhanced oil recovery and oil drilling field.

  17. Multifarious beneficial traits and plant growth promoting potential of Serratia marcescens KiSII and Enterobacter sp. RNF 267 isolated from the rhizosphere of coconut palms (Cocos nucifera L.).

    Science.gov (United States)

    George, Priya; Gupta, Alka; Gopal, Murali; Thomas, Litty; Thomas, George V

    2013-01-01

    Two plant growth promoting bacteria designated as KiSII and RNF 267 isolated from the rhizosphere of coconut palms were identified as Serratia marcescens and Enterobacter sp. based on their phenotypic features, BIOLOG studies and 16S rRNA gene sequence analysis. Both bacteria exhibited phosphate solubilization, ammonification, and production of indole acetic acid, β-1, 3 glucanase activities and 1-aminocyclopropane-1-carboxylate-deaminase activity. They could also tolerate a range of pH conditions, low temperature and salinity (NaCl). In addition, S. marcescens KiSII exhibited N- fixation potential, chitinase activity, siderophore production and antibiotics production. Seed bacterization with these bacteria increased the growth parameters of test plants such as paddy and cowpea over uninoculated control in green house assay. In coconut seedlings, significant increase in growth and nutrient uptake accompanied with higher populations of plant beneficial microorganisms in their rhizospheres were recorded on inoculation with both the PGPRs. The present study clearly revealed that PGPRs can aid in production of healthy and vigorous seedlings of coconut palm which are hardy perennial crops. They offer a scope to be developed into novel PGPR based bioinoculants for production of elite seedlings that can benefit the coconut farming community and the coconut based ecology.

  18. Enterobacter aerogenes and Enterobacter cloacae; versatile bacterial pathogens confronting antibiotic treatment

    Science.gov (United States)

    Davin-Regli, Anne; Pagès, Jean-Marie

    2015-01-01

    Enterobacter aerogenes and E. cloacae have been reported as important opportunistic and multiresistant bacterial pathogens for humans during the last three decades in hospital wards. These Gram-negative bacteria have been largely described during several outbreaks of hospital-acquired infections in Europe and particularly in France. The dissemination of Enterobacter sp. is associated with the presence of redundant regulatory cascades that efficiently control the membrane permeability ensuring the bacterial protection and the expression of detoxifying enzymes involved in antibiotic degradation/inactivation. In addition, these bacterial species are able to acquire numerous genetic mobile elements that strongly contribute to antibiotic resistance. Moreover, this particular fitness help them to colonize several environments and hosts and rapidly and efficiently adapt their metabolism and physiology to external conditions and environmental stresses. Enterobacter is a versatile bacterium able to promptly respond to the antibiotic treatment in the colonized patient. The balance of the prevalence, E. aerogenes versus E. cloacae, in the reported hospital infections during the last period, questions about the horizontal transmission of mobile elements containing antibiotic resistance genes, e.g., the efficacy of the exchange of resistance genes Klebsiella pneumoniae to Enterobacter sp. It is also important to mention the possible role of antibiotic use in the treatment of bacterial infectious diseases in this E. aerogenes/E. cloacae evolution. PMID:26042091

  19. An Enterobacter Plasmid as a New Genetic Background for the Transposon Tn1331

    Science.gov (United States)

    2011-11-25

    determined to be 99% similar to E. cloacae by both 16S rDNA and Phoenix analysis and was designated Enterobacter sp W001. Enterobacter sp W001 was...adolescents. JAMA. 2002;287(23):3096–3102. 9. Foster TJ. Plasmid- determined resistance to antimicrobial drugs and toxic metal ions in bacteria. Microbiol...mediated type II dihydrofolate reductase gene among trimethoprim -resistant urinary pathogens in Greek hospitals. J Antimicrob Chemother. 1992;29

  20. Initial Search for Triggered Gamma Emission from {sup 178}Hf{sup m2} Using the YSU Miniball Array

    Energy Technology Data Exchange (ETDEWEB)

    Carroll, J. J.; Burnett, J.; Drummond, T.; Lepak, J.; Propri, R.; Smith, D. [Youngstown State University, Department of Physics and Astronomy, Center for Photon-Induced Processes (United States); Karamian, S. A.; Adam, J. [Joint Institute for Nuclear Research (Russian Federation); Stedile, F. [Universitaet Stuttgart, Institut fuer Strahlenphysik (Germany); Agee, F. J. [Air Force Office of Scientific Research, AFOSR/NE (United States)

    2002-11-15

    Experiments with the long-lived, high-K isomer {sup 178}Hf{sup m2} have been recognized as intriguing tests of multi-quasiparticle state structures and their interactions with external radiation. A triggered release of the energy stored by this isomer, 2.5 MeV per nucleus or 1.2 GJ/gram, in the form of a gamma-ray burst might prove valuable for numerous applications. The observation of 'accelerated' decay of {sup 178}Hf{sup m2} during irradiation by 90-keV bremsstrahlung has already been reported, but with poor statistical accuracy due to the experimental approach. That approach employed single Ge detectors to seek increases in the areas of peaks at energies corresponding to transitions in the spontaneous decay of the isomer. The need for better quality data to confirm those results has motivated the development of improved detection concepts. One such concept was utilized here to perform an initial search for low-energy (<20 keV) triggered gamma emission from {sup 178}Hf{sup m2} using the YSU miniball detector array.

  1. BIOTIPE ISOLAT LOKAL ENTEROBACTER SAKAZAKII

    Directory of Open Access Journals (Sweden)

    Iza Ayu Saufani

    2016-05-01

    Full Text Available Enterobacter sakazakii telah diklasifikasikan ke dalam 16 biogrup berdasarkan sifat biokimianya dan menjadi 3 biogrup berdasarkan 20 reaksi biokimia dengan perangkat cepat API 20E. Pada tahun 2007, Iversen mengklasifikasi ulang Enterobacter sakazakii menjadi Cronobacter spp. berdasarkan sifat genotip dan biokimia seperti uji indol, pemanfaatan malonat, dan kemampuannya memproduksi asam dari dulsitol serta metil-α-D-glukosida. Pengelompokan berdasarkan sifat biokimia terhadap genus dan spesies ini belum banyak dilakukan. Penelitian ini bertujuan untuk mengelompokkan Enterobacter sakazakii yang telah diisolasi dan terkonfirmasi menggunakan PCR berdasarkan gen penyandi 16S rRNA-nya pada penelitian sebelumnya. Pengelompokan dilakukan dengan menggunakan perangkat cepat RapID ONE® dan 4 reaksi biokimia Iversen. Hasil klasifikasi menggunakan RapID ONE® kemudian dibandingkan dengan hasil klasifikasi menggunakan API 20E yang telah dilaporkan sebelumnya. Dengan menggunakan RapID ONE diperoleh 9 isolat Enterobacter sakazakii, 9 isolat Enterobacter cloacae dan 1 isolat Enterobacter cancerogenus dari 19 isolat yang diteliti. Kesembilan belas isolat uji tersebut dapat dikelompokkan menjadi 16 biotipe. Jika dibandingkan dengan menggunakan API 20E, terdapat 8 isolat yang juga teridentifikasi sebagai Enterobacter sakazakii. Berdasarkan 4 reaksi biokimia Iversen, 15 dari 19 isolat di atas dapat diklasifikasikan ke dalam Cronobacter spp. Uji pirolidonil disarankan untuk mengklasifikasikan 4 isolat yang tidak terklasifikasi dengan 4 reaksi biokimia Iversen.

  2. Enterobacter Asburiae Pneumonia with Cavitation

    International Nuclear Information System (INIS)

    Cha, Seung Woo; Heo, Jeong Nam; Park, Choong Ki; Choi, Yo Won; Jeon, Seok Chol

    2013-01-01

    Enterobacter species have increasingly been identified as pathogens over the past several decades. These bacterial species have become more important because most are resistant to cephalothin and cefoxitin, and can produce extended-spectrum β-lactamase. Enterobacter asburiae (E. asburiae) is a gram-negative rod of the family Enterobacteriaceae, named in 1986. Since then, there has been only one clinical report of E. asburiae pneumonia. We report a case of E. asburiae pneumonia with cavitation and compare it with the previous case.

  3. Enterobacter Asburiae Pneumonia with Cavitation

    Energy Technology Data Exchange (ETDEWEB)

    Cha, Seung Woo; Heo, Jeong Nam; Park, Choong Ki [Dept. of Radiology, Hanyang University College of Medicine, Guri Hospital, Guri (Korea, Republic of); Choi, Yo Won; Jeon, Seok Chol [Dept. of Radiology, Hanyang University College of Medicine, Seoul Hospital, Seoul (Korea, Republic of)

    2013-03-15

    Enterobacter species have increasingly been identified as pathogens over the past several decades. These bacterial species have become more important because most are resistant to cephalothin and cefoxitin, and can produce extended-spectrum {beta}-lactamase. Enterobacter asburiae (E. asburiae) is a gram-negative rod of the family Enterobacteriaceae, named in 1986. Since then, there has been only one clinical report of E. asburiae pneumonia. We report a case of E. asburiae pneumonia with cavitation and compare it with the previous case.

  4. Isolation, identification, characterization, and evaluation of cadmium removal capacity of Enterobacter species.

    Science.gov (United States)

    Abbas, Syed Zaghum; Rafatullah, Mohd; Ismail, Norli; Lalung, Japareng

    2014-12-01

    This study focused on the isolation and characterization of high cadmium-resistant bacterial strains, possible exploitation of its cadmium-accumulation and cadmium-induced proteins. Cadmium-resistant bacterial strains designated as RZ1 and RZ2 were isolated from industrial wastewater of Penang, Malaysia. These isolates were identified as Enterobacter mori and Enterobacter sp. WS12 on the basis of phenotypic, biochemical and 16S rDNA sequence based molecular phylogenetic characteristics. Both isolates were Gram negative, cocci, and growing well in Lauria-Bertani broth medium at 35 °C temperature and pH 7.0. Results also indicated that Enterobacter mori and Enterobacter sp. WS12are capable to remove 87.75 and 85.11% of the cadmium from 100 µg ml(-1) concentration, respectively. This study indicates that these strains can be useful as an inexpensive and efficient bioremediation technology to remove and recover the cadmium from wastewater. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Plant growth promoting potential and phylogenetic characteristics of a lichenized nitrogen fixing bacterium, Enterobacter cloacae.

    Science.gov (United States)

    Swamy, Chidanandamurthy Thippeswamy; Gayathri, Devaraja; Devaraja, Thimmalapura Neelakantaiah; Bandekar, Mandar; D'Souza, Stecy Elvira; Meena, Ram Murti; Ramaiah, Nagappa

    2016-12-01

    Lichens are complex symbiotic association of mycobionts, photobionts, and bacteriobionts, including chemolithotropic bacteria. In the present study, 46 lichenized bacteria were isolated by conventional and enrichment culture methods on nitrogen-free bromothymol blue (NFb) medium. Only 11 of the 46 isolates fixed nitrogen on NFb and had reduced acetylene. All these 11 isolates had also produced siderophore and 10 of them the IAA. Further, ammonia production was recorded from nine of these nitrogen fixers (NF). On molecular characterization, 16 S rRNA sequencing recorded that, nine NF belonged to Proteobacteria, within Gammaproteobacteria, and were closely related to Enterobacter sp. with a maximum similarity to Enterobacter cloacae. Each one of our NF isolates was aligned closely to Enterobacter pulveris strain E443, Cronobacter sakazakii strain PNP8 and Providencia rettgeri strain ALK058. Notably, a few strains we examined found to possess plant growth promoting properties. This is the first report of Enterobacter sp. from lichens which may be inhabit lichen thalli extrinsically or intrinsically. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Genomic diversity within the enterobacter cloacae complex

    NARCIS (Netherlands)

    Paauw, A.; Caspers, M.P.M.; Schuren, F.H.J.; Leverstein-van Hall, M.A.; Delétoile, A.; Montijn, R.C.; Verhoef, J.; Fluit, A.C.

    2008-01-01

    Background: Isolates of the Enterobacter cloacae complex have been increasingly isolated as nosocomial pathogens, but phenotypic identification of the E. cloacae complex is unreliable and irreproducible. Identification of species based on currently available genotyping tools is already superior to

  7. Enterobacter Strains Might Promote Colon Cancer.

    Science.gov (United States)

    Yurdakul, Dilşad; Yazgan-Karataş, Ayten; Şahin, Fikrettin

    2015-09-01

    Many studies have been performed to determine the interaction between bacterial species and cancer. However, there has been no attempts to demonstrate a possible relationship between Enterobacter spp. and colon cancer so far. Therefore, in the present study, it is aimed to investigate the effects of Enterobacter strains on colon cancer. Bacterial proteins were isolated from 11 Enterobacter spp., one Morganella morganii, and one Escherichia coli strains, and applied onto NCM460 (Incell) and CRL1790 (ATCC) cell lines. Cell viability and proliferation were determined in MTS assay. Flow Cytometry was used to detect CD24 level and apoptosis. Real-Time PCR studies were performed to determine NFKB and Bcl2 expression. Graphpad Software was used for statistical analysis. The results showed that proteins, isolated from the Enterobacter spp., have significantly increased cell viability and proliferation, while decreasing the apoptosis of the cell lines tested. The data in the present study indicated that Enterobacter strains might promote colon cancer. Moreover, Enterobacter spp. could be a clinically important factor for colon cancer initiation and progression. Studies can be extended on animal models in order to develop new strategies for treatment.

  8. Characterization of drug resistant Enterobacter species isolated from ...

    African Journals Online (AJOL)

    Enterobacter species are emerging clinical pathogens and they play important roles in the dissemination of drug resistant traits within the food chain due to their intrinsic abilities for resistance to commonly used antibiotics such as cephalosporins. Two Enterobacter cloacae and one Enterobacter hormaechei characterized in ...

  9. Pneumonia due to Enterobacter cancerogenus infection.

    Science.gov (United States)

    Demir, Tülin; Baran, Gamze; Buyukguclu, Tuncay; Sezgin, Fikriye Milletli; Kaymaz, Haci

    2014-11-01

    Enterobacter cancerogenus (formerly known as CDC Enteric Group 19; synonym with Enterobacter taylorae) has rarely been associated with human infections, and little is known regarding the epidemiology and clinical significance of this organism. We describe a community-acquired pneumonia case in a 44-year-old female due to E. cancerogenus. Identification and antimicrobial susceptibility of the microorganism was performed by the automatized VITEK 2 Compact system (bioMerieux, France). The clinical case suggests that E. cancerogenus is a potentially pathogenic microorganism in determined circumstances; underlying diseases such as bronchial asthma, empiric antibiotic treatment, wounds, diagnostic, or therapeutic instruments.

  10. Identification and phylogeny of Enterobacter sakazakii relative to Enterobacter and Citrobacter species

    DEFF Research Database (Denmark)

    Iversen, Carol; Waddington, Michael; On, Stephen L.W.

    2004-01-01

    The phylogenetic relationships of Enterobacter sakazakii strains were investigated using 16S ribosomal DNA (rDNA) and hsp60 sequencing. Each analysis distributed E. sakazakii strains among four clusters, indicating substantial taxonomic heterogeneity. The E. sakazakii type strain 16S rDNA sequence...... was 97.8% similar to that of Citrobacter koseri but 97.0% similar to that of Enterobacter cloacae....

  11. Enterobacter nimipressuralis as a cause of pseudobacteremia

    Science.gov (United States)

    2010-01-01

    Background The clinical significance of the Enterobacter nimipressuralis as human pathogens remains unclear. Case presentations The microbiologic culture monitoring system of sterile body fluids revealed on an episode of Enterobacter cloacae and Enterobacter amnigenus in blood culture results on the same day; the antibiotic sensitivity and MIC were nearly the same for both species. First patient was a healthy woman with postmenopausal syndrome, while second patient with herpes zoster. Both patients had febrile sensations without signs of bacteremia. E. amnigenus was also cultured from the unused package of salined cotton in the container through epidemiologic investigation. The cultured Enterobacter species were all identified as E. nimipressuralis through hsp60 gene sequencing and infrequent-restriction-site PCR (IRS-PCR). Conclusion When an unusual microorganisms such as E. nimipressuralis is isolated from blood of a patient with no clinical signs of sepsis, a pseudobacteremia should be suspected. When the antibiogram and MIC test results of bacterial cultures from two or more patients are nearly the same, although the species involved may appear different, it may be necessary to prove that they are the same species through molecular methods. The microbiologic cultures monitoring system will probably help to detect pseudobacteremia and other pseudo infections through reliable and fast identification. PMID:21029473

  12. FIRST REPORT OF METALLO-β-LACTAMASES PRODUCING Enterobacter spp. STRAINS FROM VENEZUELA

    Science.gov (United States)

    Martínez, Dianny; Rodulfo, Hectorina E.; Rodríguez, Lucy; Caña, Luisa E.; Medina, Belkis; Guzman, Militza; Carreño, Numirin; Marcano, Daniel; Donato, Marcos De

    2014-01-01

    Clinical strains of Enterobacter were isolated from Cumana's Central Hospital in Venezuela, and classified as E. cloacae (21), E. aerogenes (7), E. intermedium (1), E. sakazakii (1) and three unclassified. The strains showed high levels of resistance, especially to SXT (58.1%), CRO (48.8%), CAZ (46.6%), PIP (46.4%), CIP (45.2%) and ATM (43.3%). This is the first report for South America of bla VIM-2 in two E. cloacae and one Enterobacter sp., which also showed multiple mechanisms of resistance. Both E. cloacae showed bla TEM-1, but only one showed bla CTX-M-15 gene, while no bla SHV was detected. PMID:24553611

  13. The new species Enterobacter oryziphilus sp nov and Enterobacter oryzendophyticus sp nov are key inhabitants of the endosphere of rice

    NARCIS (Netherlands)

    Hardoim, Pablo Rodrigo; Nazir, Rashid; Sessitsch, Angela; Elhottova, Dana; Korenblum, Elisa; van Overbeek, Leonard Simon; van Elsas, Jan Dirk

    2013-01-01

    Background: Six independent Gram-negative, facultatively anaerobic, non-spore-forming, nitrogen-fixing rod-shaped isolates were obtained from the root endosphere of rice grown at the International Rice Research Institute (IRRI) and investigated in a polyphasic taxonomic study. Results: The strains

  14. The new species Enterobacter oryzaphilus sp. nov. and Enterobacter oryzaendophyticus sp. nov. are key inhabitants of the endosphere of rice.

    NARCIS (Netherlands)

    Hardoim, P.R.; Nazir, R.; Sessitsch, A.; Elhottova, D.; Korenblum, E.; Overbeek, van L.S.; Elsas, J.D.

    2013-01-01

    BACKGROUND: Six independent Gram-negative, facultatively anaerobic, non-spore-forming, nitrogen-fixing rod-shaped isolates were obtained from the root endosphere of rice grown at the International Rice Research Institute (IRRI) and investigated in a polyphasic taxonomic study.
    RESULTS: The

  15. Genomic diversity within the Enterobacter cloacae complex.

    Directory of Open Access Journals (Sweden)

    Armand Paauw

    Full Text Available BACKGROUND: Isolates of the Enterobacter cloacae complex have been increasingly isolated as nosocomial pathogens, but phenotypic identification of the E. cloacae complex is unreliable and irreproducible. Identification of species based on currently available genotyping tools is already superior to phenotypic identification, but the taxonomy of isolates belonging to this complex is cumbersome. METHODOLOGY/PRINCIPAL FINDINGS: This study shows that multilocus sequence analysis and comparative genomic hybridization based on a mixed genome array is a powerful method for studying species assignment within the E. cloacae complex. The E. cloacae complex is shown to be evolutionarily divided into two clades that are genetically distinct from each other. The younger first clade is genetically more homogenous, contains the Enterobacter hormaechei species and is the most frequently cultured Enterobacter species in hospitals. The second and older clade consists of several (subspecies that are genetically more heterogeneous. Genetic markers were identified that could discriminate between the two clades and cluster 1. CONCLUSIONS/SIGNIFICANCE: Based on genomic differences it is concluded that some previously defined (clonal and heterogenic (subspecies of the E. cloacae complex have to be redefined because of disagreements with known or proposed nomenclature. However, further improved identification of the redefined species will be possible based on novel markers presented here.

  16. Enterobacter cloacae complex: clinical impact and emerging antibiotic resistance.

    Science.gov (United States)

    Mezzatesta, Maria Lina; Gona, Floriana; Stefani, Stefania

    2012-07-01

    Species of the Enterobacter cloacae complex are widely encountered in nature, but they can act as pathogens. The biochemical and molecular studies on E. cloacae have shown genomic heterogeneity, comprising six species: Enterobacter cloacae, Enterobacter asburiae, Enterobacter hormaechei, Enterobacter kobei, Enterobacter ludwigii and Enterobacter nimipressuralis, E. cloacae and E. hormaechei are the most frequently isolated in human clinical specimens. Phenotypic identification of all species belonging to this taxon is usually difficult and not always reliable; therefore, molecular methods are often used. Although the E. cloacae complex strains are among the most common Enterobacter spp. causing nosocomial bloodstream infections in the last decade, little is known about their virulence-associated properties. By contrast, much has been published on the antibiotic-resistance features of these microorganisms. In fact, they are capable of overproducing AmpC β-lactamases by derepression of a chromosomal gene or by the acquisition of a transferable ampC gene on plasmids conferring the antibiotic resistance. Many other resistance determinants that are able to render ineffective almost all antibiotic families have been recently acquired. Most studies on antimicrobial susceptibility are focused on E. cloacae, E. hormaechei and E. asburiae; these studies reported small variations between the species, and the only significant differences had no discriminating features.

  17. [Septic pylephlebitis associated with Enterobacter cloacae septicemia].

    Science.gov (United States)

    Amezyane, T; Abouzahir, A; El Kharrass, A; Bassou, D; Fatihi, J; Hammi, S; Mahassin, F; Ghafir, D; Ohayon, V

    2010-02-01

    Septic pylephlebitis or purulent thrombosis of the portal venous system generally results from a progressive extension of suppurated thrombophlebitis, secondary to an intrabdominal infection. Germs most often found are Escherichia coli and Streptococcus, isolation of Enterobacter cloacae is unusual. We report a particular observation of septic pylephlebitis associated with E. cloacae bacteremia, without biliary, digestive or pancreatic lesion on the CT-scan. The antibiotic sensitivity pattern of the isolated germ and the negative epidemiologic investigation pled in favour of community acquired infection. The infection resolved with antibiotics and anticoagulation, followed by total repermeation of the portal system. Copyright 2009 Elsevier Masson SAS. All rights reserved.

  18. Enumeration of Enterobacter cloacae after chloramine exposure.

    OpenAIRE

    Watters, S K; Pyle, B H; LeChevallier, M W; McFeters, G A

    1989-01-01

    Growth of Enterobacter cloacae on various media was compared after disinfection. This was done to examine the effects of monochloramine and chlorine on the enumeration of coliforms. The media used were TLY (nonselective; 5.5% tryptic soy broth, 0.3% yeast extract, 1.0% lactose, and 1.5% Bacto-Agar), m-T7 (selective; developed to recover injured coliforms), m-Endo (selective; contains sodium sulfite), TLYS (TLY with sodium sulfite), and m-T7S (m-T7 with sodium sulfite). Sodium sulfite in any m...

  19. Enumeration of Enterobacter cloacae after chloramine exposure.

    Science.gov (United States)

    Watters, S K; Pyle, B H; LeChevallier, M W; McFeters, G A

    1989-01-01

    Growth of Enterobacter cloacae on various media was compared after disinfection. This was done to examine the effects of monochloramine and chlorine on the enumeration of coliforms. The media used were TLY (nonselective; 5.5% tryptic soy broth, 0.3% yeast extract, 1.0% lactose, and 1.5% Bacto-Agar), m-T7 (selective; developed to recover injured coliforms), m-Endo (selective; contains sodium sulfite), TLYS (TLY with sodium sulfite), and m-T7S (m-T7 with sodium sulfite). Sodium sulfite in any medium improved the recovery of chloramine-treated E. cloacae. However, sodium sulfite in TLYS and m-T7S did not significantly improve the detection of chlorine-treated E. cloacae, and m-Endo was the least effective medium for recovering chlorinated bacteria. Differences in recovery of chlorine- and chloramine-treated E. cloacae are consistent with mechanistic differences between the disinfectants. PMID:2619309

  20. Comparative Genome Analysis of Enterobacter cloacae

    Science.gov (United States)

    Liu, Wing-Yee; Wong, Chi-Fat; Chung, Karl Ming-Kar; Jiang, Jing-Wei; Leung, Frederick Chi-Ching

    2013-01-01

    The Enterobacter cloacae species includes an extremely diverse group of bacteria that are associated with plants, soil and humans. Publication of the complete genome sequence of the plant growth-promoting endophytic E. cloacae subsp. cloacae ENHKU01 provided an opportunity to perform the first comparative genome analysis between strains of this dynamic species. Examination of the pan-genome of E. cloacae showed that the conserved core genome retains the general physiological and survival genes of the species, while genomic factors in plasmids and variable regions determine the virulence of the human pathogenic E. cloacae strain; additionally, the diversity of fimbriae contributes to variation in colonization and host determination of different E. cloacae strains. Comparative genome analysis further illustrated that E. cloacae strains possess multiple mechanisms for antagonistic action against other microorganisms, which involve the production of siderophores and various antimicrobial compounds, such as bacteriocins, chitinases and antibiotic resistance proteins. The presence of Type VI secretion systems is expected to provide further fitness advantages for E. cloacae in microbial competition, thus allowing it to survive in different environments. Competition assays were performed to support our observations in genomic analysis, where E. cloacae subsp. cloacae ENHKU01 demonstrated antagonistic activities against a wide range of plant pathogenic fungal and bacterial species. PMID:24069314

  1. Rapid identification of Enterobacter hormaechei and Enterobacter cloacae genetic cluster III.

    Science.gov (United States)

    Ohad, S; Block, C; Kravitz, V; Farber, A; Pilo, S; Breuer, R; Rorman, E

    2014-05-01

    Enterobacter cloacae complex bacteria are of both clinical and environmental importance. Phenotypic methods are unable to distinguish between some of the species in this complex, which often renders their identification incomplete. The goal of this study was to develop molecular assays to identify Enterobacter hormaechei and Ent. cloacae genetic cluster III which are relatively frequently encountered in clinical material. The molecular assays developed in this study are qPCR technology based and served to identify both Ent. hormaechei and Ent. cloacae genetic cluster III. qPCR results were compared to hsp60 sequence analysis. Most clinical isolates were assigned to Ent. hormaechei subsp. steigerwaltii and Ent. cloacae genetic cluster III. The latter was proportionately more frequently isolated from bloodstream infections than from other material (P < 0·05). The qPCR assays detecting Ent. hormaechei and Ent. cloacae genetic cluster III demonstrated high sensitivity and specificity. The presented qPCR assays allow accurate and rapid identification of clinical isolates of the Ent. cloacae complex. The improved identifications obtained can specifically assist analysis of Ent. hormaechei and Ent. cloacae genetic cluster III in nosocomial outbreaks and can promote rapid environmental monitoring. An association was observed between Ent. cloacae cluster III and systemic infection that deserves further attention. © 2014 The Society for Applied Microbiology.

  2. Identification of resistance and virulence factors in an epidemic Enterobacter hormaechei outbreak strain

    NARCIS (Netherlands)

    Paauw, A.; Caspers, M.P.M.; Leverstein-van Hall, M.A.; Schuren, F.H.J.; Montijn, R.C.; Verhoef, J.; Fluit, A.C.

    2009-01-01

    Bacterial strains differ in their ability to cause hospital outbreaks. Using comparative genomic hybridization, Enterobacter cloacae complex isolates were studied to identify genetic markers specific for Enterobacter cloacae complex outbreak strains. No outbreak-specific genes were found that were

  3. Reclassification of Enterobacter oryziphilus and Enterobacter oryzendophyticus as Kosakonia oryziphila comb. nov. and Kosakonia oryzendophytica comb. nov.

    Science.gov (United States)

    Li, Chun Yan; Zhou, Yuan Liang; Ji, Jing; Gu, Chun Tao

    2016-08-01

    The taxonomic positions of Enterobacter oryziphilus and Enterobacter oryzendophyticus were re-examined on the basis of concatenated partial rpoB, atpD, gyrB and infB gene sequence analysis. The reconstructed phylogenetic tree based upon concatenated partial rpoB, atpD, gyrB and infB gene sequences clearly showed that E. oryziphilus and E. oryzendophyticus and all defined species of the genus Kosakonia form a clade separate from other genera of the family Enterobacteriaceae, and, therefore, these species of the genus Enterobacter should be transferred to the genus Kosakonia. E. oryziphilus and E. oryzendophyticus are reclassified as K. oryziphila comb. nov. (type strain REICA_142T=LMG 26429T=NCCB 100393T) and K. oryzendophytica comb. nov. (type strain REICA_082T=LMG 26432T=NCCB 100390T), respectively.

  4. Frequency of Isolation of Enterobacter Species from a Variety of ...

    African Journals Online (AJOL)

    Purpose: To determine the frequency of occurrence of Enterobacter species and their antibiogram from clinical specimens of blood, cerebrospinal fluid, urine and wound obtained from University of Benin Teaching Hospital, Benin City, ... There was no significant difference in infection rate among the age groups (p > 0.05).

  5. The new species .i.Enterobacter oryziphilus./i. sp. nov. and .i.Enterobacter oryzendophyticus./i. sp. nov. are key inhabitants of the endosphere of rice

    Czech Academy of Sciences Publication Activity Database

    Hardoim, P.R.; Nazir, R.; Sessitsch, A.; Elhottová, Dana; Korenblum, E.; van Overbeek, L.S.; van Elsas, J.D.

    2013-01-01

    Roč. 13, July 2013 (2013), s. 164 ISSN 1471-2180 Institutional support: RVO:60077344 Keywords : plant growth-promoting bacteria * Endophytes * production of indole-3-acetic acid Subject RIV: EE - Microbiology, Virology Impact factor: 2.976, year: 2013

  6. Chemical Constituents of the Lichens Cladonia multiformis and Cryptothecia sp

    International Nuclear Information System (INIS)

    Hasliza Yusof; Husna Azahar; Laily Din; Nazlina Ibrahim

    2015-01-01

    Two depsides (atranorin 1 and evernic acid 4), an aromatic compound (methyl β-orcinolcarboxylate 2) and one cleavage product of depside (everninic acid 3) were isolated from two lichens, Cladonia multiformis (1 and 2) and Cryptothecia sp. (3 and 4). The identification of the four compounds was carried out by comparison of the recorded NMR data with that of the reported. Compounds 1 and 4 showed antibacterial activity against Bacillus subtilis and Enterobacter aerogenes. (author)

  7. A new protocol for the detection of Enterobacter sakazakii applied to environmental samples

    NARCIS (Netherlands)

    Kandhai, M.C.; Reij, M.W.; Puyvelde, van K.; Guillaume-Gentil, O.; Beumer, R.R.; Schothorst, van M.

    2004-01-01

    Enterobacter sakazakii is a motile, peritrichous, gram-negative rod that was previously known as a yellow pigmented Enterobacter cloacae. It is documented as a rare cause of outbreaks and sporadic cases of life-threatening neonatal meningitis, necrotizing enterocolitis, and sepsis. E. sakazakii has

  8. Cerebral infarctions due to CNS infection with Enterobacter sakazakii

    International Nuclear Information System (INIS)

    Gallagher, P.G.; Ball, W.S.

    1991-01-01

    Recent reports have implicated Enterobacter sakazakii, a gram-negative enteric bacillus, in neonatal sepsis and meningitis. Cases of severe central nervous system involvement, including ventriculitis, brain abscess, infarction, and cyst formation, have been described. We present serial head CT findings in a case of neonatal E. sakazakii meningitis complicated by a ring enhancing cerebral infarction which mimicked abscess formation. In meningitis secondary to this agent, a recognized pattern of cerebral hypodensity with or without cystic degeneration late in the course of the infection is likely to represent cerebral infarction rather than an abscess especially if there is a lack of culture evidence of a bacterial infection. (orig.)

  9. Microbiological Features of KPC-Producing Enterobacter Isolates Identified in a U.S. Hospital System

    Science.gov (United States)

    Ahn, Chulsoo; Syed, Alveena; Hu, Fupin; O’Hara, Jessica A.; Rivera, Jesabel I.; Doi, Yohei

    2014-01-01

    Microbiological data regarding KPC-producing Enterobacter spp. are scarce. In this study, 11 unique KPC-producing Enterobacter isolates were identified among 44 ertapenem-non-susceptible Enterobacter isolates collected between 2009 and 2013 at a hospital system in Western Pennsylvania. All cases were healthcare-associated and occurred in medically complex patients. While pulsed-field gel electrophoresis (PFGE) showed diverse restriction patterns overall, multilocus sequence typing (MLST) identified Enterobacter cloacae isolates with sequence types (STs) 93 and 171 from two hospitals each. The levels of carbapenem minimum inhibitory concentrations were highly variable. All isolates remained susceptible to colistin, tigecycline, and the majority to amikacin and doxycycline. A blaKPC-carrying IncN plasmid conferring trimethoprim-sulfamethoxazole resistance was identified in three of the isolates. Spread of blaKPC in Enterobacter spp. appears to be due to a combination of plasmid-mediated and clonal processes. PMID:25053203

  10. The differential importance of mutations within AmpD in cephalosporin resistance of Enterobacter aerogenes and Enterobacter cloacae.

    Science.gov (United States)

    Babouee Flury, Baharak; Ellington, Matthew J; Hopkins, Katie L; Turton, Jane F; Doumith, Michel; Woodford, Neil

    2016-11-01

    Mechanisms leading to carbapenem and cephalosporin resistance were sought in Enterobacter aerogenes isolates that were highly resistant to carbapenems but had no known carbapenemase. Results were compared with recent work examining carbapenem-resistant Enterobacter cloacae. Eighteen carbapenem-resistant E. aerogenes were screened for known β-lactamase and carbapenemase genes, and novel carbapenemases were sought in whole-genome sequencing (WGS) data of the three most resistant isolates. For all isolates, ampC, ampR, ampD and the porin genes omp35 and omp36 were investigated by Sanger sequencing or from available WGS data. Expression of ampC and porin genes was measured in comparison with cephalosporin- and carbapenem-susceptible control strains by reverse transcriptase PCR, with porin translation also detected by SDS-PAGE. Loss of Omp35, primarily due to decreased transcription (up to 250×), was observed in ertapenem-resistant isolates (MICs ≥ 2 mg/L), whereas meropenem resistance (MICs ≥ 4 mg/L) was observed in those isolates also showing decreased or no production of Omp36. Loss of Omp36 was due to combinations of premature translation termination or reduced transcription. In contrast to E. cloacae, cephalosporin resistance in E. aerogenes was not associated with lesions in AmpD. High-level cefepime resistance (MIC = 32 mg/L) was caused by a novel modification in the H-10 helix of AmpC in one isolate. The differential importance of AmpD lesions in cephalosporin resistance in E. cloacae and E. aerogenes underlines the differences between these contrasting members of the Enterobacter genus. Porin loss resulted in high-level carbapenem resistance with gradual loss of Omp36, which led to high-level meropenem resistance. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

  11. Temporal Trends in Enterobacter Species Bloodstream Infection: A Population-Based Study, 1998-2007

    Science.gov (United States)

    Al-Hasan, Majdi N.; Lahr, Brian D.; Eckel-Passow, Jeanette E.; Baddour, Larry M.

    2010-01-01

    Enterobacter species are the fourth most common cause of gram-negative bloodstream infection (BSI). We examined temporal changes and seasonal variation in the incidence rate of Enterobacter spp. BSI, estimated 28-day and 1-year mortality, and determined in vitro antimicrobial resistance rates of Enterobacter spp. bloodstream isolates in Olmsted County, Minnesota, from 1/1/1998 to 12/31/2007. Multivariable Poisson regression was used to examine temporal changes and seasonal variation in incidence rate and Kaplan-Meier method to estimate 28-day and 1-year mortality. The median age of patients with Enterobacter spp. BSI was 58 years and 53% were female. The overall age- and gender-adjusted incidence rate of Enterobacter spp. BSI was 3.3/100,000 person-years (95% confidence interval [CI]: 2.3-4.4). There was a linear trend of increasing incidence rate from 0.8 (95% CI: 0-1.9) to 6.2 (95% CI: 3.0-9.3) per 100,000 person-years between 1998 and 2007 (p=0.002). There was no significant difference in the incidence rate of Enterobacter spp. BSI during the warmest four months compared to the remainder of the year (incidence rate ratio 1.06 [95% CI: 0.47-2.01]). The overall 28-day and 1-year mortality rates of Enterobacter spp. BSI were 21% (95% CI: 8-34%) and 38% (95% CI: 22-53%), respectively. Up to 13% of Enterobacter spp. bloodstream isolates were resistant to third-generation cephalosporins. To our knowledge, this is the first population-based study to describe the epidemiology and outcome of Enterobacter spp. BSI. The increase in incidence rate of Enterobacter spp. BSI over the past decade, coupled with its associated antimicrobial resistance, dictate more investigation of this syndrome. PMID:20518795

  12. Purification and characterization of thermoalkalophilic xylanase isolated from the Enterobacter sp. MTCC 5112

    Digital Repository Service at National Institute of Oceanography (India)

    Khandeparker, R.; Bhosle, N.B.

    at 50 oC and pH 9 the enzyme remained stable for days. For xylan, the enzyme gave a Km value of 3.3 mg/ml, and Vmax value of 5000 µmol.min-1. mg-1 when the reaction was carried out at 100 oC and pH 9. In the presence of metal ions such as Co+2, Zn+2 , Fe...

  13. Thermodynamic study and optimization of hydrogen production by Enterobacter aerogenes

    Energy Technology Data Exchange (ETDEWEB)

    Fabiano, B.; Perego, P. [University of Genova (Italy). Chemical and Process Engineering Department ' G.B. Bonino'

    2002-02-01

    This paper investigates the influence of pH and temperature on hydrogen bioproduction by Enterobacter aerogenes (NCIMB 10102) utilizing starch hydrolysate as substrate. An optimum pH range corresponding to 6.1-6.6 is the main evidence of batch runs carried out at different pHs. An optimum value of temperature corresponding to 40{sup o}C is experimentally determined by means of batch fermentation runs carried out at different operative temperatures. A thermodynamic study, which was performed developing the Arrhenius approach, allows the estimation, for both fermentation and thermal inactivation, of the activation enthalpies (67.3 and 118.1 kJmol{sup -1}) and of the correlated entropies (-0.087 and -0.46 kJmol{sup -1} K{sup -1}). (author)

  14. Phenotypic changes contributing to Enterobacter gergoviae biocide resistance.

    Science.gov (United States)

    Périamé, M; Philippe, N; Condell, O; Fanning, S; Pagès, J-M; Davin-Regli, A

    2015-08-01

    Enterobacter gergoviae is a recurrent contaminant of cosmetic and hygiene products. To understand how this bacterium adapts to biocides, we studied Ent. gergoviae CIP 76.01 and its triclosan and Methylisothiazolinone-chloromethylisothiazolinone (MIT-CMIT) tolerant isogenic mutants. They were compared with others also isolated from contaminated cosmetics. Phenotypic differences were noted and these included changes in the bacterial envelope and flagella along with differences in motility, and biofilm growth rates. Triclosan and MIT-CMIT derivatives expressed flagella and other MIT-CMIT derivatives exhibited some external appendages. Those bacteria expressing a high-level minimal inhibitory concentration to MIT-CMIT, expressed a strong biofilm formation. No differential phenotypes were noted for carbon source utilisation. Enterobacter gergoviae demonstrated a diverse response to both of these preservatives contained in cosmetic preparations, depending on their concentrations. Interestingly, this adaptive response is associated with modifications of filament structure-related proteins contributing to increase the organism motility and the production of biofilm. Recurrent contaminations of cosmetics products by Ent. gergoviae, needed a better understanding concerning the bacterial adaptation to preservative agents, with particular concern to triclosan and MIT-CMIT. We demonstrated that bacteria response is associated to various mechanisms represented by expression of external appendages (pili or fimbriae) that control cell motility and biofilm formation and evolving as the concentration of biocides adaptation increased. Such mechanisms which are not chemical specific can also promote a cross-resistance to other biocidal agents. The characterization of Ent. gergoviae adaptability to biocides allows industry to adjust the ranges of concentrations and composition of preservatives in formula. © 2015 The Society for Applied Microbiology.

  15. Kinetic characterization of a novel acid ectophosphatase from Enterobacter asburiae.

    Science.gov (United States)

    Sato, Vanessa Sayuri; Galdiano Júnior, Renato F; Rodrigues, Gisele Regina; Lemos, Eliana G M; Pizauro Junior, João Martins

    2016-02-01

    Expression of acid ectophosphatase by Enterobacter asburiae, isolated from Cattleya walkeriana (Orchidaceae) roots and identified by the 16S rRNA gene sequencing analysis, was strictly regulated by phosphorus ions, with its optimal activity being observed at an inorganic phosphate concentration of 7 mM. At the optimum pH 3.5, intact cells released p-nitrophenol at a rate of 350.76 ± 13.53 nmol of p-nitrophenolate (pNP)/min/10(8) cells. The membrane-bound enzyme was obtained by centrifugation at 100,000 × g for 1 h at 4 °C. p-Nitrophenylphosphate (pNPP) hydrolysis by the enzyme follows "Michaelis-Menten" kinetics with V = 61.2 U/mg and K0.5 = 60 μM, while ATP hydrolysis showed V = 19.7 U/mg, K0.5 = 110 μM, and nH = 1.6 and pyrophosphate hydrolysis showed V = 29.7 U/mg, K0.5 = 84 μM, and nH = 2.3. Arsenate and phosphate were competitive inhibitors with K i = 0.6 mM and K i = 1.8 mM, respectively. p-Nitrophenyl phosphatase (pNPPase) activity was inhibited by vanadate, while p-hydroxymercuribenzoate, EDTA, calcium, copper, and cobalt had no inhibitory effects. Magnesium ions were stimulatory (K0.5 = 2.2 mM and nH = 0.5). Production of an acid ectophosphatase can be a mechanism for the solubilization of mineral phosphates by microorganisms such as Enterobacter asburiae that are versatile in the solubilization of insoluble minerals, which, in turn, increases the availability of nutrients for plants, particularly in soils that are poor in phosphorus.

  16. Isolation of Cronobacter spp. (Enterobacter sakazakii from artisanal mozzarella

    Directory of Open Access Journals (Sweden)

    Francesco Casalinuovo

    2014-02-01

    Full Text Available Cronobacter spp. (Enterobacter sakazakii is an opportunistic bacterial pathogen capable of causing disease and even fatalities in newborn infants within the first weeks of life if consumed as part of the diet. Premature and immunocompromised newborn infants are at particular risk. The microorganism has been isolated from a variety of foods including contaminated infant milk formula powder and milk powder substitute. The study aimed to evaluate the level of microbiological contamination in 47 samples of mozzarella cheese made with cow’s milk collected from artisan cheese producers in Southern Italy. Samples were collected from commercial sales points and underwent qualitative and quantitative microbiological analyses to test for the bacterial contaminants most commonly found in milk and cheese products. The 47 samples underwent qualitative and quantitative microbiological tests according to ISO UNI EN standards. Analyses focused on Staphylococcus aures, Salmonella spp., Listeria monocytogenes, Pseudomonas spp., E. coli, Yersinia spp., total coliforms and Cronobacter sakazakii. The ISO/TS 22964:2006 method was used to investigate possible contamination by C. sakazakii. Biochemical identification was carried out using an automated system for identification and susceptibility tests. None of the samples examined resulted positive for Salmonella spp. or Listeria spp. Only one sample resulted positive for Staphylococcus aureus. Pseudomonas spp. was isolated in 10 (21% of 47 samples. High levels of total coliforms were found in 10 of 47 samples. Cronobacter spp. (Enterobacter sakazakii was isolated in one sample. This is the first study to confirm isolation of C. sakazakii in artisan mozzarella cheese made from cow’s milk. The presence of C. sakazakii could be related to external contamination during the phases of production or to the use of contaminated milk. Since mozzarella is recommended in the diet of children and adults of all ages, this

  17. Eight-Year Surveillance of Antimicrobial Resistance among Enterobacter Cloacae Isolated in the First Bethune Hospital

    Science.gov (United States)

    Zhou, Qi; Zhang, Man; Wang, Ailin; Xu, Jiancheng; Yuan, Ye

    This study was to investigate the antimicrobial resistance of Enterobacter cloacae isolated in 8 consecutive years in the First Bethune Hospital. Disk diffusion test was used to study the antimicrobial resistance. The data were analyzed by WHONET 5 software according to Clinical and Laboratory Standards Institute (CLSI). Most of 683 strains of Enterobacter cloacae were collected from sputum 410 (60.0%), secretions and pus 105 (15.4%), urine 69 (10.1%) during the past 8 years. No Enterobacter cloacae was resistant to imipenem and meropenem in the First Bethune Hospital. The antimicrobial resistance of Enterobacter cloacae had increased in recent 8 years. The change of the antimicrobial resistance should be investigated in order to direct rational drug usage in the clinic and prevent bacterial strain of drug resistance from b eing transmitted.

  18. Risk Factors for Emergence of Resistance to Broad-Spectrum Cephalosporins among Enterobacter spp.

    Science.gov (United States)

    Kaye, Keith S.; Cosgrove, Sara; Harris, Anthony; Eliopoulos, George M.; Carmeli, Yehuda

    2001-01-01

    Among 477 patients with susceptible Enterobacter spp., 49 subsequently harbored third-generation cephalosporin-resistant Enterobacter spp. Broad-spectrum cephalosporins were independent risk factors for resistance (relative risk [OR] = 2.3, P = 0.01); quinolone therapy was protective (OR = 0.4, P = 0.03). There were trends toward decreased risk for resistance among patients receiving broad-spectrum cephalosporins and either aminoglycosides or imipenem. Of the patients receiving broad-spectrum cephalosporins, 19% developed resistance. PMID:11502540

  19. Epidemiology of extended spectrum β-lactamase producing Enterobacter bacteremia in a brazilian hospital Epidemiologia de bacteremia causadas por Enterobacter produtores de β-lactamases de espectro estendido em um hospital brasileiro

    Directory of Open Access Journals (Sweden)

    Felipe Francisco Tuon

    2010-08-01

    Full Text Available INTRODUCTION: Enterobacter can be included in the group of extended spectrum β-lactamases (EBSL-producing bacteria, though few studies exist evaluating risk factors associated with this microorganism. A retrospective cohort study was conducted to determine risk factors associated with ESBL-producing-Enterobacter and mortality METHODS: A retrospective cohort study with 58 bacteremia caused by ESBL-producing-Enterobacter (28 cases and non-ESBL (30 cases RESULTS: Risk factors associated with ESBL-Enterobacter were trauma, length of hospitalization, admission to the intensive care unit, urinary catheter and elective surgery (pINTRODUÇÃO: Enterobacter pode ser incluído no grupo de bactérias produtoras de β-lactamases de espectro estendido (ESBL, mas existem poucos estudos avaliando fatores de risco para ESBL. Nós realizamos uma coorte retrospective para determiner fatores de risco associados com Enterobacter produtores de ESBL MÉTODOS: Uma coorte retrospectiva com 58 bacteremias por Enterobacter ESBL (28 casos e não-ESBL (30 casos RESULTADOS: Fatores de risco para ESBL-Enterobacter foram trauma, tempo de internação, admissão em UTI, sonda vesical e cirurgia eletiva (p<0.05. A mortalidade foi similar entre ESBL e não-ESBL CONCLUSÕES: Enterobacter produtor de ESBL é prevalente e a curva de mortalidade foi semelhante com o grupo não-ESBL.

  20. Prevalence and characterization of multidrug-resistant zoonotic Enterobacter spp. in poultry of Bangladesh.

    Science.gov (United States)

    Nandi, Shuvro Prokash; Sultana, Munawar; Hossain, M Anwar

    2013-05-01

    Poultry and poultry products are major contributors of zoonotic pathogens. Limited data are available on Enterobacter spp. as a potent zoonotic pathogen in poultry. The present study is a first endeavor on the emergence of multidrug-resistant zoonotic Enterobacter spp. and its prevalence arising from poultry in Bangladesh. Cloacal swabs from poultry samples of five different farms at Savar, Dhaka, Bangladesh were collected and from 106 isolates, 18 presumptive Enterobacter spp. were obtained. Antibiogram using 19 used antibiotics belonging to 15 major groups revealed that all of the 18 isolates were completely resistant to penicillin and rifampicin, but differed in their drug resistance pattern against ampicillin (94.4%), clindamycin (94.4%), erythromycin (94.4%), vancomycin (88.9%), sulfonamides (72.2%), imipenem (66.6%), streptomycin (55.6%), nitrofurantoin (33.3%), doxycycline (33.3%), tetracyclines (33.3%), cefepime (11.1%), and gentamicin (5.6%). All Enterobacter spp. were found to be plasmid free, implying that multidrug-resistant properties are chromosomal borne. The vanA and sulI were detected by polymerase chain reaction assay in 17 and 13 isolates, respectively. Amplified ribosomal DNA restriction analysis and randomly amplified polymorphic DNA distributed the 18 multidrug-resistant Enterobacter spp. into three genotypes. Phylogenetic analysis of the representatives of the three genotypes using partial 16S rRNA gene sequence (approximately 900 bp) showed that the genotypically diverse groups belonged to Enterobacter hormaechei, E. cloacae, and E. cancerogenus, respectively. The clinical significance of the close relative Enterobacter spp. is indicative of their zoonotic potential. Therefore, urgent intervention is required to limit the emergence and spread of these bacteria in poultry feed as well as prudent use of antibiotics among poultry farmers in Bangladesh.

  1. Re-examination of the taxonomic status of Enterobacter helveticus, Enterobacter pulveris and Enterobacter turicensis as members of the genus Cronobacter and their reclassification in the genera Franconibacter gen. nov. and Siccibacter gen. nov. as Franconibacter helveticus comb. nov., Franconibacter pulveris comb. nov. and Siccibacter turicensis comb. nov., respectively.

    Science.gov (United States)

    Stephan, Roger; Grim, Christopher J; Gopinath, Gopal R; Mammel, Mark K; Sathyamoorthy, Venugopal; Trach, Larisa H; Chase, Hannah R; Fanning, Séamus; Tall, Ben D

    2014-10-01

    Recently, a taxonomical re-evaluation of the genus Enterobacter, based on multi-locus sequence typing (MLST) analysis, has led to the proposal that the species Enterobacter pulveris, Enterobacter helveticus and Enterobacter turicensis should be reclassified as novel species of the genus Cronobacter. In the present work, new genome-scale analyses, including average nucleotide identity, genome-scale phylogeny and k-mer analysis, coupled with previously reported DNA-DNA hybridization values and biochemical characterization strongly indicate that these three species of the genus Enterobacter are not members of the genus Cronobacter, nor do they belong to the re-evaluated genus Enterobacter. Furthermore, data from this polyphasic study indicated that all three species constitute two new genera. We propose reclassifying Enterobacter pulveris and Enterobacter helveticus in the genus Franconibacter gen. nov. as Franconibacter pulveris comb. nov. (type strain 601/05(T) = LMG 24057(T) = DSM 19144(T)) and Franconibacter helveticus comb. nov. (type strain 513/05(T) = LMG 23732(T) = DSM 18396(T)), respectively, and Enterobacter turicensis in the genus Siccibacter gen. nov. as Siccibacter turicensis comb. nov. (type strain 508/05(T) = LMG 23730(T) = DSM 18397(T)).

  2. An Enterobacter plasmid as a new genetic background for the transposon Tn1331

    Directory of Open Access Journals (Sweden)

    Alavi MR

    2011-11-01

    Full Text Available Mohammad R Alavi1,2, Vlado Antonic2, Adrien Ravizee1, Peter J Weina3, Mina Izadjoo1,2, Alexander Stojadinovic21Division of Wound Biology and Translational Research, Armed Forces Institute of Pathology and American Registry of Pathology, Washington DC, 2Combat Wound Initiative Program, Walter Reed Army Medical Center, Washington DC, 3The Walter Reed Army Institute of Research, Silver Spring, MD, USABackground: Genus Enterobacter includes important opportunistic nosocomial pathogens that could infect complex wounds. The presence of antibiotic resistance genes in these microorganisms represents a challenging clinical problem in the treatment of these wounds. In the authors’ screening of antibiotic-resistant bacteria from complex wounds, an Enterobacter species was isolated that harbors antibiotic-resistant plasmids conferring resistance to Escherichia coli. The aim of this study was to identify the resistance genes carried by one of these plasmids.Methods: The plasmids from the Enterobacter isolate were propagated in E. coli and one of the plasmids, designated as pR23, was sequenced by the Sanger method using fluorescent dye-terminator chemistry on a genetic analyzer. The assembled sequence was annotated by search of the GenBank database.Results: Plasmid pR23 is composed of the transposon Tn1331 and a backbone plasmid that is identical to the plasmid pPIGDM1 from Enterobacter agglomerans. The multidrug-resistance transposon Tn1331, which confers resistance to aminoglycoside and beta lactam antibiotics, has been previously isolated only from Klebsiella. The Enterobacter plasmid pPIGDM1, which carries a ColE1-like origin of replication and has no apparent selective marker, appears to provide a backbone for propagation of Tn1331 in Enterobacter. The recognition sequence of Tn1331 transposase for insertion into pPIGDM1 is the pentanucleotide TATTA, which occurs only once throughout the length of this plasmid.Conclusion: Transposition of Tn1331 into

  3. Treatment outcomes in patients with third-generation cephalosporin-resistant Enterobacter bacteremia.

    Science.gov (United States)

    O'Neal, Catherine S; O'Neal, Hollis R; Daniels, Titus L; Talbot, Thomas R

    2012-10-01

    Infections with resistant Enterobacter spp. are increasingly described, yet data on outcomes associated with these infections are limited. A retrospective cohort study was conducted to investigate outcomes of hospitalized patients with third-generation cephalosporin-resistant (CR) Enterobacter bacteremia. Cephalosporin resistance was detected using cefotaxime and cefpodoxime. Patients with Enterobacter spp. bacteremia from January 2006 through February 2008 defined the population. We defined cases as those with CR isolates; controls were patients with bacteremia due to non-CR isolates. Treatment failure was defined as persistence of the presenting signs of infection 72 h after initial culture collection. Of the 95 Enterobacter cases identified, 31 (33%) were CR. CR cases were significantly associated with treatment failure (odds ratio (OR) 2.81, 95% confidence interval (CI) 1.14-6.94). This association was not seen after adjustment for age, simplified acute physiology score (SAPS II), and inappropriate empiric antibiotic therapy. Inappropriate empiric therapy (adjusted OR 3.86, 95% CI 1.32-11.31) and SAPS II score (adjusted OR 1.09, 95% CI 1.02-1.16) were significantly associated with treatment failure in the multivariate analysis. Third-generation cephalosporin-resistant Enterobacter bacteremia is associated with treatment failure due to receipt of inappropriate empiric antibiotic therapy and severity of illness.

  4. Hydrocarbon degradation, plant colonization and gene expression of alkane degradation genes by endophytic Enterobacter ludwigii strains

    International Nuclear Information System (INIS)

    Yousaf, Sohail; Afzal, Muhammad; Reichenauer, Thomas G.; Brady, Carrie L.; Sessitsch, Angela

    2011-01-01

    The genus Enterobacter comprises a range of beneficial plant-associated bacteria showing plant growth promotion. Enterobacter ludwigii belongs to the Enterobacter cloacae complex and has been reported to include human pathogens but also plant-associated strains with plant beneficial capacities. To assess the role of Enterobacter endophytes in hydrocarbon degradation, plant colonization, abundance and expression of CYP153 genes in different plant compartments, three plant species (Italian ryegrass, birdsfoot trefoil and alfalfa) were grown in sterile soil spiked with 1% diesel and inoculated with three endophytic E. ludwigii strains. Results showed that all strains were capable of hydrocarbon degradation and efficiently colonized the rhizosphere and plant interior. Two strains, ISI10-3 and BRI10-9, showed highest degradation rates of diesel fuel up to 68% and performed best in combination with Italian ryegrass and alfalfa. All strains expressed the CYP153 gene in all plant compartments, indicating an active role in degradation of diesel in association with plants. - Highlights: → E. ludwigii strains efficiently colonized plants in a non-sterile soil environment. → E. ludwigii strains efficiently expressed alkane degradation genes in plants. → E. ludwigii efficiently degraded alkane contaminations and promoted plant growth. → E. ludwigii interacted more effectively with Italian ryegrass than with other plants. → Degradation activity varied with plant and microbial genotype as well as with time. - Enterobacter ludwigii strains belonging to the E. cloacae complex are able to efficiently degrade alkanes when associated with plants and to promote plant growth.

  5. Hydrocarbon degradation, plant colonization and gene expression of alkane degradation genes by endophytic Enterobacter ludwigii strains

    Energy Technology Data Exchange (ETDEWEB)

    Yousaf, Sohail [AIT Austrian Institute of Technology GmbH, Bioresources Unit, A-2444 Seibersdorf (Austria); Afzal, Muhammad [AIT Austrian Institute of Technology GmbH, Bioresources Unit, A-2444 Seibersdorf (Austria); National Institute for Biotechnology and Genetic Engineering (NIBGE), Faisalabad (Pakistan); Reichenauer, Thomas G. [AIT Austrian Institute of Technology GmbH, Environmental Resources and Technologies Unit, A-2444 Seibersdorf (Austria); Brady, Carrie L. [Forestry and Agricultural Biotechnology Institute, Department of Microbiology and Plant Pathology, University of Pretoria, Pretoria (South Africa); Sessitsch, Angela, E-mail: angela.sessitsch@ait.ac.at [AIT Austrian Institute of Technology GmbH, Bioresources Unit, A-2444 Seibersdorf (Austria)

    2011-10-15

    The genus Enterobacter comprises a range of beneficial plant-associated bacteria showing plant growth promotion. Enterobacter ludwigii belongs to the Enterobacter cloacae complex and has been reported to include human pathogens but also plant-associated strains with plant beneficial capacities. To assess the role of Enterobacter endophytes in hydrocarbon degradation, plant colonization, abundance and expression of CYP153 genes in different plant compartments, three plant species (Italian ryegrass, birdsfoot trefoil and alfalfa) were grown in sterile soil spiked with 1% diesel and inoculated with three endophytic E. ludwigii strains. Results showed that all strains were capable of hydrocarbon degradation and efficiently colonized the rhizosphere and plant interior. Two strains, ISI10-3 and BRI10-9, showed highest degradation rates of diesel fuel up to 68% and performed best in combination with Italian ryegrass and alfalfa. All strains expressed the CYP153 gene in all plant compartments, indicating an active role in degradation of diesel in association with plants. - Highlights: > E. ludwigii strains efficiently colonized plants in a non-sterile soil environment. > E. ludwigii strains efficiently expressed alkane degradation genes in plants. > E. ludwigii efficiently degraded alkane contaminations and promoted plant growth. > E. ludwigii interacted more effectively with Italian ryegrass than with other plants. > Degradation activity varied with plant and microbial genotype as well as with time. - Enterobacter ludwigii strains belonging to the E. cloacae complex are able to efficiently degrade alkanes when associated with plants and to promote plant growth.

  6. Isolation of Enterobacter cowanii in tomatoes after gamma irradiation

    International Nuclear Information System (INIS)

    Vicalvi, M.C.V.; Solidonio, E.G.; Silva, M.A.; Colaco, W.; Silva, G.R. da; Sena, K.X.F.R de

    2013-01-01

    The tomato is one of the most consumed fruit in the world. Bacteria of the family Enterobacteriaceae are responsible for large outbreaks of gastroenteritis. Irradiation is a physical method which reduces waste by eliminating spoilage organisms in foods. The objective of this study was to identify and determine the resistance profile of micro-organisms of the family Enterobacteriaceae from irradiated tomatoes. Were used three batches each containing 80 tomatoes, and divided in control and irradiated. The samples were individually properly identified as the irradiation dose applied. The material was subjected to irradiation with gamma rays, for irradiating with a cobalt-60 source, using doses: 1.0, 1.5 and 2 kGy (6,060 kGy/h). For microbiological analysis tomatoes were cut out, and removing the shells to obtain samples weighing 25g. Each sample was transferred to an Erlenmeyer containing sterilized water, stirring the assembly mechanically. Aliquots of the wash waters were sown in differential and selective media. After reisolation, the colonies were subjected to Gram staining then performed biochemical tests for identification. The antibiotic susceptibility tests were performed according to CLSI (Clinical Laboratory Standard Institute). It was isolated three strains of Enterobacter cowanii in tomato samples irradiated with a dose of 1.0 kGy, without isolating the other doses. As for the resistance profile, the strains were resistant to Ampicillin identified. Gamma irradiation at a dose of 1.5 and 2 kGy was effective in tomatoes as well as the micro-organism isolated after irradiation showed no profile of multidrug resistance. (author)

  7. Genome Sequence of the Enterobacter mori Type Strain, LMG 25706, a Pathogenic Bacterium of Morus alba L. ▿

    Science.gov (United States)

    Zhu, Bo; Zhang, Guo-Qing; Lou, Miao-Miao; Tian, Wen-Xiao; Li, Bin; Zhou, Xue-Ping; Wang, Guo-Feng; Liu, He; Xie, Guan-Lin; Jin, Gu-Lei

    2011-01-01

    Enterobacter mori is a plant-pathogenic enterobacterium responsible for the bacterial wilt of Morus alba L. Here we present the draft genome sequence of the type strain, LMG 25706. To the best of our knowledge, this is the first genome sequence of a plant-pathogenic bacterium in the genus Enterobacter. PMID:21602328

  8. Disinfection of deionised water inoculated with enterobacter using ultra violet light

    International Nuclear Information System (INIS)

    Mathrani, M.

    2001-01-01

    For the first time the enterobacter, not the escherichia coli,was used as a model bacteria to asses the disinfection of microorganisms in water by UV (Ultra Violet) irradiation. The cell density of the liquid culture was followed by optical density of 1.837 at 600 nm on spectrometer. For the disinfection purpose, a laboratory scale batch reactor (10 cm wide, 20 cm long, and 10 cm height), containing 250 ml sterilised deionized water inoculated with enterobacter,was run under supra-band gap light (wavelength < 400 nm, peaking between 340 and 365 nm with a maximum of 350 nm). After carrying out seven batch experiments it is concluded that the complete inactivation of Enterobacter ( approx. equal to x 10/sup 6/ CFU/ml) in the water can be achieved by UV irradiation for 2 hours. (author)

  9. Isolation of Enterobacter cowanii in tomatoes after gamma irradiation; Isolamento de Enterobacter cowanii em tomates apos irradiacao gama

    Energy Technology Data Exchange (ETDEWEB)

    Vicalvi, M.C.V.; Solidonio, E.G.; Silva, M.A.; Colaco, W., E-mail: claudiavicalvi@hotmail.com [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Programa de Pos Graduacao em Tecnologias Energeticas e Nucleares; Silva, G.R. da; Sena, K.X.F.R de [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Lab. de Antibioticos

    2013-08-15

    The tomato is one of the most consumed fruit in the world. Bacteria of the family Enterobacteriaceae are responsible for large outbreaks of gastroenteritis. Irradiation is a physical method which reduces waste by eliminating spoilage organisms in foods. The objective of this study was to identify and determine the resistance profile of micro-organisms of the family Enterobacteriaceae from irradiated tomatoes. Were used three batches each containing 80 tomatoes, and divided in control and irradiated. The samples were individually properly identified as the irradiation dose applied. The material was subjected to irradiation with gamma rays, for irradiating with a cobalt-60 source, using doses: 1.0, 1.5 and 2 kGy (6,060 kGy/h). For microbiological analysis tomatoes were cut out, and removing the shells to obtain samples weighing 25g. Each sample was transferred to an Erlenmeyer containing sterilized water, stirring the assembly mechanically. Aliquots of the wash waters were sown in differential and selective media. After reisolation, the colonies were subjected to Gram staining then performed biochemical tests for identification. The antibiotic susceptibility tests were performed according to CLSI (Clinical Laboratory Standard Institute). It was isolated three strains of Enterobacter cowanii in tomato samples irradiated with a dose of 1.0 kGy, without isolating the other doses. As for the resistance profile, the strains were resistant to Ampicillin identified. Gamma irradiation at a dose of 1.5 and 2 kGy was effective in tomatoes as well as the micro-organism isolated after irradiation showed no profile of multidrug resistance. (author)

  10. Biological Conversion of Glycerol to Ethanol by Enterobacter aerogenes

    Science.gov (United States)

    Nwachukwu, Raymond E. S.

    In a search to turn the economically and environmentally non-valuable "waste" streams of biodiesel production into a profitable byproduct, a mutant strain of Enterobacter aerogenes ATCC 13048 was developed by six-tube subculturing technique. This technique is based on the principle of adaptive evolution, and involved subculturing the bacterium in a tryptic soy broth without dextrose (TSB) containing specific glycerol and ethanol concentration for six consecutive times. Then, the six consecutive subculturing was repeated in a fresh TSB of higher glycerol and ethanol concentrations. A new mutant strain, E. aerogenes S012, which could withstand a combination of 200 g/l glycerol and 30 g/l ethanol concentrations, was developed. The wild and mutant strains were used for the fermentation of pure (P-) and recovered (R-) glycerol. Taguchi and full factorial methods of design of experiments were used to screen and optimize the important process factors that influence the microbial production of ethanol. A statistically sound regression model was used to establish the mathematical relationship between the process variables and ethanol production. Temperature of 38°C, agitation speed of 200 rpm, pH of 6.3-6.6, and microaerobic condition were the optimum process conditions. Different pretreatment methods to recover glycerol from the crude glycerol and the subsequent fermentation method showed that direct acidification using 85% H3PO4 was the best. The R-glycerol contained 51% pure glycerol and 21% methanol. The wild strain, E. aerogenes ATCC 13048, produced only 12 g/l and 12.8 g/l ethanol from 20 g/l P- and R-glycerol respectively, and could not utilize higher glycerol concentrations. The mutant, E. aerogenes S012, produced ethanol amount and yield of 43 g/l and 1.12 mol/mol-glycerol from P-glycerol, respectively within 96 h. It also produced ethanol amount and yield of 26.8 g/l and 1.07 mol/mol-glycerol, respectively, from R-glycerol within the same duration. In a

  11. Computational-based structural, functional and phylogenetic analysis of Enterobacter phytases.

    Science.gov (United States)

    Pramanik, Krishnendu; Kundu, Shreyasi; Banerjee, Sandipan; Ghosh, Pallab Kumar; Maiti, Tushar Kanti

    2018-06-01

    Myo-inositol hexakisphosphate phosphohydrolases (i.e., phytases) are known to be a very important enzyme responsible for solubilization of insoluble phosphates. In the present study, Enterobacter phytases have characterized by different phylogenetic, structural and functional parameters using some standard bio-computational tools. Results showed that majority of the Enterobacter phytases are acidic in nature as most of the isoelectric points were under 7.0. The aliphatic indices predicted for the selected proteins were below 40 indicating their thermostable nature. The average molecular weight of the proteins was 48 kDa. The lower values of GRAVY of the said proteins implied that they have better interactions with water. Secondary structure prediction revealed that alpha-helical content was highest among the other forms such as sheets, coils, etc. Moreover, the predicted 3D structure of Enterobacter phytases divulged that the proteins consisted of four monomeric polypeptide chains i.e., it was a tetrameric protein. The predicted tertiary model of E. aerogenes (A0A0M3HCJ2) was deposited in Protein Model Database (Acc. No.: PM0080561) for further utilization after a thorough quality check from QMEAN and SAVES server. Functional analysis supported their classification as histidine acid phosphatases. Besides, multiple sequence alignment revealed that "DG-DP-LG" was the most highly conserved residues within the Enterobacter phytases. Thus, the present study will be useful in selecting suitable phytase-producing microbe exclusively for using in the animal food industry as a food additive.

  12. Alterations in the response of pigs to Salmonella typhimurium when provided Enterobacter cloacae

    Science.gov (United States)

    Weanling pigs are at risk of succumbing to illness due to an immature immune system and insufficient supply of available energy at the time of weaning. Recent evidence has suggested that providing pigs with Enterobacter cloacae can increase the concentration of circulating triglycerides (TAGs) and t...

  13. Clinical analysis of Enterobacter bacteremia in pediatric patients: a 10-year study.

    Science.gov (United States)

    Chen, Hui-Lan; Lu, Jen-Her; Wang, Hsin-Hui; Chen, Shu-Jen; Chen, Chun-Jen; Wu, Keh-Gong; Tang, Ren-Bin

    2014-10-01

    Enterobacter species has emerged as an important pathogen of nosocomial bacteremia. The purpose of this study is to review the clinical characteristics of bacteremia in pediatric patients. We reviewed retrospectively the medical records of patients (under the age of 18 years) having Enterobacter bacteremia who were treated at Taipei the Veterans General Hospital from January 2001 to June 2011. In total, 853 positive blood cultures were obtained from 620 patients during the study period. Among them, 96 episodes of Enterobacter bacteremia were found in 83 patients, accounting for 11.3% of all bacteremia. Eighty-two cases (98.8%) were nosocomial infections. Most of the cases were neonates (62 cases, 74.7%) and premature infants (51 cases, 61.5%). The common sources of bacteremia were the respiratory tract (53.0%), followed by intravascular catheter (10.8%), multiple sources (10.8%), and the gastrointestinal tract (8.4%). The overall case fatality rate was 18.1%, with the highest rate being reported among premature infants. The factors responsible for the deaths were leukocytosis and a higher median number of underlying diseases. Based on the findings of the present study, it can be concluded that Enterobacter species are probably an important pathogen of nosocomial bacteremia in premature neonates. The number of underlying diseases should be considered a major factor influencing the prognosis. Copyright © 2013. Published by Elsevier B.V.

  14. The status of the species Enterobacter siamensisKhunthongpan et al. 2014. Request for an Opinion.

    Science.gov (United States)

    Kämpfer, Peter; Doijad, Swapnil; Chakraborty, Trinad; Glaeser, Stefanie P

    2016-01-01

    In the course of a taxonomic study describing novel species of the genus Enterobacter it was found that the 16S rRNA gene sequence of the type strain of Enterobacter siamensis, obtained both directly from the authors of the publication on Enterobacter siamensis and from the Korean Collection for Type Cultures (C2361T and KCTC 23282T, respectively), was not congruent with the 16S rRNA gene sequence deposited in the GenBank database under the accession number HQ888848, which was applied for phylogenetic analysis in the species proposal. The remaining deposit in the Japanese type culture collection, NBRC 107138T, showed an identical 16S rRNA gene sequence to the other two cultures and overall, this sequence differed at 35 positions in comparison with the 1429 bp sequence published under the accession number HQ888848.Therefore, the type strain of this species cannot be included in any further scientific comparative study. It is proposed that the Judicial Commission of the International Committee on Systematics of Prokaryotes place the name Enterobacter siamensis on the list of rejected names, if a suitable replacement for the type strain is not found or a neotype strain is not proposed within two years following the publication of this Request for an Opinion.

  15. Simultaneous production of hydrogen and ethanol from waste glycerol by Enterobacter aerogenes KKU-S1

    DEFF Research Database (Denmark)

    Reungsang, Alissara; Sittijunda, Sureewan; Angelidaki, Irini

    2013-01-01

    Factors affecting simultaneous hydrogen and ethanol production from waste glycerol by a newly isolated bacterium Enterobacter aerogenes KKU-S1 were investigated employing response surface methodology (RSM) with central composite design (CCD). The Plackett-Burman design was first used to screen...

  16. Meningoencephalitis and Compartmentalization of the Cerebral Ventricles Caused by Enterobacter sakazakii

    Science.gov (United States)

    Kleiman, Martin B.; Allen, Stephen D.; Neal, Patricia; Reynolds, Janet

    1981-01-01

    A necrotizing meningoencephalitis complicated by ventricular compartmentalization and abscess formation caused by Enterobacter sakazakii in a previously healthy 5-week-old female is described. A detailed description of the isolate is presented. This communication firmly establishes the pathogenicity of E. sakazakii. PMID:7287892

  17. Cefepime vs other antibacterial agents for the treatment of Enterobacter species bacteremia.

    Science.gov (United States)

    Siedner, Mark J; Galar, Alicia; Guzmán-Suarez, Belisa B; Kubiak, David W; Baghdady, Nour; Ferraro, Mary Jane; Hooper, David C; O'Brien, Thomas F; Marty, Francisco M

    2014-06-01

    Carbapenems are recommended for treatment of Enterobacter infections with AmpC phenotypes. Although isolates are typically susceptible to cefepime in vitro, there are few data supporting its clinical efficacy. We reviewed all cases of Enterobacter species bacteremia at 2 academic hospitals from 2005 to 2011. Outcomes of interest were (1) persistent bacteremia ≥1 calendar day and (2) in-hospital mortality. We fit logistic regression models, adjusting for clinical risk factors and Pitt bacteremia score and performed propensity score analyses to compare the efficacy of cefepime and carbapenems. Three hundred sixty-eight patients experienced Enterobacter species bacteremia and received at least 1 antimicrobial agent, of whom 52 (14%) died during hospitalization. Median age was 59 years; 19% were neutropenic, and 22% were in an intensive care unit on the day of bacteremia. Twenty-nine (11%) patients had persistent bacteremia for ≥1 day after antibacterial initiation. None of the 36 patients who received single-agent cefepime (0%) had persistent bacteremia, as opposed to 4 of 16 (25%) of those who received single-agent carbapenem (P Enterobacter species bacteremia. Its use should be further explored as a carbapenem-sparing agent in this clinical scenario.

  18. Biotransformation of Ferulic acid to 4-Vinylguaiacol by Enterobacter soli and E. aerogenes

    Science.gov (United States)

    We investigated the conversion of ferulic acid to 4-vinylguaiacol (4-VG), vanillin, vanillyl alcohol and vanillic acid by five Enterobacter strains. These high-value chemicals are usually synthesized using chemical methods but biological synthesis adds value. Ferulic acid, a relatively inexpensive...

  19. A simple and rapid cultural method for detection of Enterobacter sakazakii in environmental samples

    NARCIS (Netherlands)

    Guillaume-Gentil, O.; Sonnard, V.; Kandhai, M.C.; Marugg, J.; Joosten, H.

    2005-01-01

    A method was developed to detect and identify Enterobacter sakazakii in environmental samples. The method is based on selective enrichment at 45 ± 0.5°C in lauryl sulfate tryptose broth supplemented with 0.5 M NaCl and 10 mg/liter vancomycin (mLST) for 22 to 24 h followed by streaking on tryptone

  20. Molecular characteristics of extended-spectrum beta-lactamases and qnr determinants in Enterobacter species from Japan.

    Science.gov (United States)

    Kanamori, Hajime; Yano, Hisakazu; Hirakata, Yoichi; Hirotani, Ayako; Arai, Kazuaki; Endo, Shiro; Ichimura, Sadahiro; Ogawa, Miho; Shimojima, Masahiro; Aoyagi, Tetsuji; Hatta, Masumitsu; Yamada, Mitsuhiro; Gu, Yoshiaki; Tokuda, Koichi; Kunishima, Hiroyuki; Kitagawa, Miho; Kaku, Mitsuo

    2012-01-01

    The incidence of extended-spectrum β-lactamases (ESBLs) has been increasing worldwide, but screening criteria for detection of ESBLs are not standardized for AmpC-producing Enterobacteriaceae such as Enterobacter species. In this study, we investigated the prevalence of ESBLs and/or AmpC β-lactamases in Japanese clinical isolates of Enterobacter spp. and the association of plasmid-mediated quinolone resistance (PMQR) determinants with ESBL producers. A total of 364 clinical isolates of Enterobacter spp. collected throughout Japan between November 2009 and January 2010 were studied. ESBL-producing strains were assessed by the CLSI confirmatory test and the boronic acid disk test. PCR and sequencing were performed to detect CTX-M, TEM, and SHV type ESBLs and PMQR determinants. For ESBL-producing Enterobacter spp., pulsed-field gel electrophoresis (PFGE) was performed using XbaI restriction enzyme. Of the 364 isolates, 22 (6.0%) were ESBL producers. Seven isolates of Enterobacter cloacae produced CTX-M-3, followed by two isolates producing SHV-12. Two isolates of Enterobacter aerogenes produced CTX-M-2. Of the 22 ESBL producers, 21 had the AmpC enzyme, and six met the criteria for ESBL production in the boronic acid test. We found a significant association of qnrS with CTX-M-3-producing E. cloacae. The 11 ESBL-producing Enterobacter spp. possessing bla(CTX-M), bla(SHV), or bla(TEM) were divided into six unique PFGE types. This is the first report about the prevalence of qnr determinants among ESBL-producing Enterobacter spp. from Japan. Our results suggest that ESBL-producing Enterobacter spp. with qnr determinants are spreading in Japan.

  1. Comprehensive Genome Analysis of Carbapenemase-Producing Enterobacter spp.: New Insights into Phylogeny, Population Structure, and Resistance Mechanisms.

    Science.gov (United States)

    Chavda, Kalyan D; Chen, Liang; Fouts, Derrick E; Sutton, Granger; Brinkac, Lauren; Jenkins, Stephen G; Bonomo, Robert A; Adams, Mark D; Kreiswirth, Barry N

    2016-12-13

    Knowledge regarding the genomic structure of Enterobacter spp., the second most prevalent carbapenemase-producing Enterobacteriaceae, remains limited. Here we sequenced 97 clinical Enterobacter species isolates that were both carbapenem susceptible and resistant from various geographic regions to decipher the molecular origins of carbapenem resistance and to understand the changing phylogeny of these emerging and drug-resistant pathogens. Of the carbapenem-resistant isolates, 30 possessed bla KPC-2 , 40 had bla KPC-3 , 2 had bla KPC-4 , and 2 had bla NDM-1 Twenty-three isolates were carbapenem susceptible. Six genomes were sequenced to completion, and their sizes ranged from 4.6 to 5.1 Mbp. Phylogenomic analysis placed 96 of these genomes, 351 additional Enterobacter genomes downloaded from NCBI GenBank, and six newly sequenced type strains into 19 phylogenomic groups-18 groups (A to R) in the Enterobacter cloacae complex and Enterobacter aerogenes Diverse mechanisms underlying the molecular evolutionary trajectory of these drug-resistant Enterobacter spp. were revealed, including the acquisition of an antibiotic resistance plasmid, followed by clonal spread, horizontal transfer of bla KPC -harboring plasmids between different phylogenomic groups, and repeated transposition of the bla KPC gene among different plasmid backbones. Group A, which comprises multilocus sequence type 171 (ST171), was the most commonly identified (23% of isolates). Genomic analysis showed that ST171 isolates evolved from a common ancestor and formed two different major clusters; each acquiring unique bla KPC -harboring plasmids, followed by clonal expansion. The data presented here represent the first comprehensive study of phylogenomic interrogation and the relationship between antibiotic resistance and plasmid discrimination among carbapenem-resistant Enterobacter spp., demonstrating the genetic diversity and complexity of the molecular mechanisms driving antibiotic resistance in this

  2. Purification and characterization of [Fe]-hydrogenase from high yielding hydrogen-producing strain, Enterobacter cloacae IIT-BT08 (MTCC 5373)

    Energy Technology Data Exchange (ETDEWEB)

    Dutta, Tumpa; Das, Amit Kumar; Das, Debabrata [Department of Biotechnology, Indian Institute of Technology, Kharagpur, WB 721302 (India)

    2009-09-15

    Fe-hydrogenase from Enterobacter cloacae IIT-BT08 was purified 1284 fold with specific activity of 335 {mu}mol H{sub 2}/min/mg protein for hydrogen evolution using reduced methyl viologen as an electron-donor at 25 C. The molecular weight of the monomeric enzyme was determined to be 51 kDa by MALDI-ToF mass spectrometry. The PI of the enzyme was {proportional_to}5.6 displaying its acidic nature. The optimal temperature and pH for hydrogen evolution was 37 C and 7-7.2 respectively. The affinity constant, K{sub m} for reduced methyl viologen was 0.57 {+-} 0.03 mM and that of reduced ferredoxin was 0.72 {+-} 0.04 {mu}M. The enzyme contained {proportional_to}11.47 gm-atom Fe/mol of Fe-hydrogenase. Electron paramagnetic resonance analysis ascertained the existence of iron molecules as [4Fe-4S] clusters. The internal amino acid sequences of trypsin digested peptides of hydrogenase as determined by ESI MS/MS Q-ToF showed 80-87% identities with the respective sequences of Clostridium sp. and Trichomonas sp. hydrogenase. (author)

  3. Enterobactérias isoladas de baratas (Periplaneta americana capturadas em um hospital brasileiro

    Directory of Open Access Journals (Sweden)

    Marinésia A. Prado

    2002-02-01

    Full Text Available Objetivo. Isolar e identificar microrganismos em baratas capturadas em um hospital público e determinar o seu perfil de suscetibilidade antimicrobiana. Métodos. As baratas foram capturadas nos períodos matutino e noturno, colocadas em frascos desinfetados com álcool a 70%, transferidas para um frasco estéril e levadas ao laboratório. Consideraram-se as baratas íntegras e vivas, as quais foram colocadas em solução salina estéril (0,8% e homogeneizadas. Essa solução foi semeada nos meios de cultura ágar MacConkey, caldo nutriente, infusão de cérebro e coração (ágar BHI, ágar Sabouraud e ágar manitol. As culturas foram examinadas em um estereomicroscópio para a contagem das unidades formadoras de colônias. Para a determinação do perfil de suscetibilidade antimicrobiana utilizou-se o teste de difusão de disco. Resultados. Detectou-se prevalência de 56% de enterobactérias e de 18% de estafilococos coagulase negativos. Identificaram-se 15 espécies de enterobactérias. As mais freqüentes foram Klebsiella pneumoniae (17%; Enterobacter aerogenes (14%; Serratia marcescens (13%; Hafnia alvei (12%; Enterobacter gergoviae e Enterobacter cloacae (9%; e Serratia spp. (6%. Tanto as enterobactérias quanto os estafilococos coagulase negativos apresentaram uma resistência significativa aos antimicrobianos, inclusive à oxacilina. Conclusões. A prevalência de bactérias enteropatogênicas e de estafilococos coagulase negativos isolados de baratas Periplaneta americana no hospital estudado demonstra a fragilidade das condutas adotadas tanto para o controle de vetores quanto para o uso dos antimicrobianos. Os resultados demonstram a necessidade da implementação de um programa efetivo de saneamento ambiental e do uso racional dos antimicrobianos dentro das instituições de saúde.

  4. Enterobactérias isoladas de baratas (Periplaneta americana capturadas em um hospital brasileiro

    Directory of Open Access Journals (Sweden)

    Prado Marinésia A.

    2002-01-01

    Full Text Available Objetivo. Isolar e identificar microrganismos em baratas capturadas em um hospital público e determinar o seu perfil de suscetibilidade antimicrobiana. Métodos. As baratas foram capturadas nos períodos matutino e noturno, colocadas em frascos desinfetados com álcool a 70%, transferidas para um frasco estéril e levadas ao laboratório. Consideraram-se as baratas íntegras e vivas, as quais foram colocadas em solução salina estéril (0,8% e homogeneizadas. Essa solução foi semeada nos meios de cultura ágar MacConkey, caldo nutriente, infusão de cérebro e coração (ágar BHI, ágar Sabouraud e ágar manitol. As culturas foram examinadas em um estereomicroscópio para a contagem das unidades formadoras de colônias. Para a determinação do perfil de suscetibilidade antimicrobiana utilizou-se o teste de difusão de disco. Resultados. Detectou-se prevalência de 56% de enterobactérias e de 18% de estafilococos coagulase negativos. Identificaram-se 15 espécies de enterobactérias. As mais freqüentes foram Klebsiella pneumoniae (17%; Enterobacter aerogenes (14%; Serratia marcescens (13%; Hafnia alvei (12%; Enterobacter gergoviae e Enterobacter cloacae (9%; e Serratia spp. (6%. Tanto as enterobactérias quanto os estafilococos coagulase negativos apresentaram uma resistência significativa aos antimicrobianos, inclusive à oxacilina. Conclusões. A prevalência de bactérias enteropatogênicas e de estafilococos coagulase negativos isolados de baratas Periplaneta americana no hospital estudado demonstra a fragilidade das condutas adotadas tanto para o controle de vetores quanto para o uso dos antimicrobianos. Os resultados demonstram a necessidade da implementação de um programa efetivo de saneamento ambiental e do uso racional dos antimicrobianos dentro das instituições de saúde.

  5. Phage types, antibiograms and R-plasmids of Klebsiella and Enterobacter isolated from hospital environment and food.

    Science.gov (United States)

    Horváth, J; Lantos, J; Fekete, J; Marjai, E

    1986-01-01

    Four-hundred and twenty-two Klebsiella strains and 294 Enterobacter strains were isolated from direct or indirect environment of hospitalized patients, from foodstuffs, foods, culinary utensils and staff in hospital and in catering establishments. Of Klebsiella, the species K. aerogenes (76.5%) of Enterobacter, the species E. cloacae (77.6%) occurred the most frequently in all specimens. Klebsiella strains were typable in 68.5%; 53.1% of the Enterobacter strains were sensitive to phage. Most of the untypable Klebsiella and Enterobacter strains and the multiresistant strains originated from screening in hospitals. Sensitive bacteria as well as those resistant to one or two antibiotics may be potentially dangerous for the patient consuming them, since they may become multiresistant due to R-plasmid transfer.

  6. [New Enterobacteriaceae found in medical bacteriology Moellerella wisconsensis, Koserella trabulsii, Leclercia adecarboxylata, Escherichia fergusonii, Enterobacter asbutiae, Rahnella aquatilis].

    Science.gov (United States)

    Richard, C

    1989-01-01

    Characteristics of 6 "new" Enterobacteriaceae species, occasionally isolated from human sources: Moellerella wisconsensis, Koserella trabulsii, Leclercia adecarboxylata, Escherichia fergusonii, Rahnella aquatilis, Enterobacter asburiae are described and compared with those of closely related species.

  7. SP. Pescado

    Directory of Open Access Journals (Sweden)

    Renato Gendre

    2003-12-01

    Full Text Available Nell'occhiello di un articolo dal titolo Il Peru dei de[Jini rosa e de/la grande pioggia si legge: "da una partenza  in aereo al «pescado»  che ti  sfamera."1 Questa parola spagnola, giustamente chiusa tra caporali, a noi pare molto interes­ sante, perche, nonostante l'apparenza, non ha nulla da spartire sotto i1 profilo se­ mantico con l'it. pescato. lnfatti, tutti i piu importanti dizionari della lingua italiana, di ieri e di oggi, etimologici e non 2, registrano  accanto a pescata,  ii lemma pescato, 3 ma lo spiegano come "quantita di pesce catturato nel corso di una battuta o di una stagione di pesca",4 mentre lo sp. pescado  indica i1 "pesce (solo nel senso di: pesGe pescato da mangiare [...]".s

  8. Method for Phenotypic Detection of Extended-Spectrum Beta-Lactamases in Enterobacter Species in the Routine Clinical Setting ▿

    Science.gov (United States)

    Stuart, James Cohen; Diederen, Bram; al Naiemi, Nashwan; Fluit, Ad; Arents, Niek; Thijsen, Steven; Vlaminckx, Bart; Mouton, Johan W.; Leverstein-van Hall, Maurine

    2011-01-01

    In 271 Enterobacter blood culture isolates from 12 hospitals, extended-spectrum beta-lactamase (ESBL) prevalence varied between 0% and 30% per hospital. High prevalence was associated with dissemination, indicating the potential relevance of infection control measures. Screening with cefepime or Vitek 2, followed by a cefepime/cefepime-clavulanate Etest, was an accurate strategy for ESBL detection in Enterobacter isolates (positive predictive value, 100%; negative predictive value, 99%). PMID:21562100

  9. DAN IDENTIFIKASI PATOGEN POTENSIAL YANG MENGINFEKSI IKAN RAINBOW (Melanotaenia sp.

    Directory of Open Access Journals (Sweden)

    Lili Sholichah

    2014-03-01

    ., Lactobacillus sp., Bacillus sp., Arachnia sp., Haemophilus sp., Cardiobacterium sp., dan Enterobacter sp. sedangkan jamur tidak ditemukan dalam penelitian ini.

  10. My 40-Year History with Cronobacter/Enterobacter sakazakii -- Lessons Learned, Myths Debunked, and Recommendations

    Directory of Open Access Journals (Sweden)

    John J Farmer III

    2015-11-01

    Full Text Available Much has been learned about Cronobacter/Enterobacter sakazakii since I first named and described Enterobacter sakazakii in 1980. However, there are still wide knowledge gaps. One of the most serious is that are still many uncertainties associated with assessing the public health risk from these bacteria, particularly in neonatal meningitis. Over the last few decades Cronobacter contamination of commercial powdered infant formula has apparently been reduced, but it is still an ongoing problem. The powdered infant formula industry still cannot produce powdered formula that is free of bacterial contamination with Cronobacter, other Enterobacteriaceae, and other pathogenic bacteria. Until this happens infants and other will be at risk of becoming infected when contaminated product is ingested.

  11. KPC and VIM producing Enterobacter cloacae strain from a hospital in northeastern Venezuela.

    Science.gov (United States)

    Martínez, Dianny; Marcano, Daniel; Rodulfo, Hectorina; Salgado, Nurys; Cuaical, Nirvia; Rodriguez, Lucy; Caña, Luisa; Medina, Belkis; Guzman, Militza; De Donato, Marcos

    2015-06-01

    An 83-year-old male patient is admitted to the central hospital in Cumana, Venezuela with severe urinary infection, history of hospitalizaions and prolonged antimicrobial treatments. A strain of Enterobacter cloacae was isolated showing resistance to multiple types of antibiotics (only sensitive to gentamicin), with phenotype of serine- and metallo-carbapenemases. Both, bla(VIM-2) and bla(KPC) genes were detected in the isolate. This is the first report of an Enterobacteriaceae species producing both KPC carbapenemase and VIM metallo carbapenemase in Venezuela. This finding has a great clinical and epidemiological impact in the region, because of the feasibility of transferring these genes, through mobile elements to other strains of Enterobacter and to other infection-causing species of bacteria.

  12. The Complex Epidemiology of Carbapenem-Resistant Enterobacter Infections: A Multicenter Descriptive Analysis.

    Science.gov (United States)

    Lazarovitch, Tsilia; Amity, Keren; Coyle, Joseph R; Ackerman, Benjamin; Tal-Jasper, Ruthy; Ofer-Friedman, Hadas; Hayakawa, Kayoko; Bogan, Christopher; Lephart, Paul R; Kaplansky, Tamir; Maskit, Moran; Azouri, Tal; Zaidenstein, Ronit; Perez, Federico; Bonomo, Robert A; Kaye, Keith S; Marchaim, Dror

    2015-11-01

    The pandemic of carbapenem-resistant Enterobacteriaceae (CRE) was primarily due to clonal spread of bla KPC producing Klebsiella pneumoniae. Thus, thoroughly studied CRE cohorts have consisted mostly of K. pneumoniae. To conduct an extensive epidemiologic analysis of carbapenem-resistant Enterobacter spp. (CREn) from 2 endemic and geographically distinct centers. CREn were investigated at an Israeli center (Assaf Harofeh Medical Center, January 2007 to July 2012) and at a US center (Detroit Medical Center, September 2008 to September 2009). bla KPC genes were queried by polymerase chain reaction. Repetitive extragenic palindromic polymerase chain reaction and pulsed-field gel electrophoresis were used to determine genetic relatedness. In this analysis, 68 unique patients with CREn were enrolled. Sixteen isolates (24%) were from wounds, and 33 (48%) represented colonization only. All isolates exhibited a positive Modified Hodge Test, but only 93% (27 of 29) contained bla KPC. Forty-three isolates (63%) were from elderly adults, and 5 (7.4%) were from neonates. Twenty-seven patients died in hospital (40.3% of infected patients). Enterobacter strains consisted of 4 separate clones from Assaf Harofeh Medical Center and of 4 distinct clones from Detroit Medical Center. In this study conducted at 2 distinct CRE endemic regions, there were unique epidemiologic features to CREn: (i) polyclonality, (ii) neonates accounting for more than 7% of cohort, and (iii) high rate of colonization (almost one-half of all cases represented colonization). Since false-positive Modified Hodge Tests in Enterobacter spp. are common, close monitoring of carbapenem resistance mechanisms (particularly carbapenemase production) among Enterobacter spp. is important.

  13. Identification of an operon involved in fluoride resistance in Enterobacter cloacae FRM

    OpenAIRE

    Liu, Xiaoqing; Tian, Jian; Liu, Lihui; Zhu, Tao; Yu, Xiaoxia; Chu, Xiaoyu; Yao, Bin; Wu, Ningfeng; Fan, Yunliu

    2017-01-01

    Fluorine is ubiquitous and the most active non-metal element in nature. While many microorganisms have developed fluoride resistance as a result of the widespread and prolonged application of oral hygiene products, the mechanisms used by these organisms to overcome fluoride toxicity are incompletely understood. In this study, a fluoride-resistant strain, Enterobacter cloacae FRM, was identified which could grow well at a fluoride concentration of 4,000?mg/L. According to comparative genomics,...

  14. Genetic characterisation of tigecycline-resistant Enterobacter spp. in blood isolates causing bacteraemia.

    Science.gov (United States)

    Cha, Min Kyeong; Kang, Cheol-In; Park, Ga Eun; Kim, So Hyun; Chung, Doo Ryeon; Peck, Kyong Ran; Song, Jae-Hoon

    2018-01-05

    Tigecycline (TIG) is one of the most important antimicrobial agents used to treat infections by multidrug-resistant bacteria. However, rates of TIG-resistant pathogens have increased recently. This study was conducted to identify the antimicrobial susceptibility profiles and to investigate the role of efflux pumps in high-level TIG-resistant Enterobacter spp. isolates causing bacteraemia. A total of 323 Enterobacter spp. causing bacteraemia were collected from eight hospitals in various regions of South Korea. Minimum inhibitory concentrations (MICs) were determined by the broth microdilution method and Etest. Expression levels of the efflux pump gene acrA and its regulators (ramA and rarA) were examined by quantitative real-time PCR. Isolate relatedness was determined by multilocus sequence typing (MLST). Among the 323 clinical isolates included in this study, 37 (11.5%) were TIG-non-susceptible, of which 8 isolates were highly resistant to TIG with MICs of 8mg/L (4 isolates) or 16mg/L (4 isolates). All high-level TIG-resistant isolates showed increased expression of acrA (0.93-13.3-fold) and ramA (1.4-8.2-fold). Isolates with a tigecycline MIC of 16mg/L also showed overexpression of rarA compared with TIG-susceptible isolates. In this study, overexpression of acrA, ramA and rarA was observed in high-level TIG-resistant Enterobacter spp. isolates. We suggest that rarA might be involved in the regulation of acrA overexpression in high-level TIG-resistant Enterobacter spp. isolates. Efflux pump-mediated resistance should be closely monitored because it could be indirectly attributed to the use of other antibiotics transported by the same efflux pump. Copyright © 2017. Published by Elsevier Ltd.

  15. Characterization of rhamnolipids produced by non-pathogenic Acinetobacter and Enterobacter bacteria

    Czech Academy of Sciences Publication Activity Database

    Hošková, M.; Schreiberová, O.; Ježdík, R.; Chudoba, J.; Masák, M.; Sigler, Karel; Řezanka, Tomáš

    2013-01-01

    Roč. 130, FEB 2013 (2013), s. 510-516 ISSN 0960-8524 R&D Projects: GA ČR(CZ) GAP503/11/0215 Grant - others:GA MPO(CZ) FR-TI1/456 Institutional support: RVO:61388971 Keywords : Pseudomonas aeruginosa * Acinetobacter calcoaceticus * Enterobacter asburiae Subject RIV: EE - Microbiology, Virology Impact factor: 5.039, year: 2013

  16. Impact of glycerol and nitrogen concentration on Enterobacter A47 growth and exopolysaccharide production.

    Science.gov (United States)

    Torres, Cristiana A V; Marques, Rodolfo; Ferreira, Ana R V; Antunes, Sílvia; Grandfils, Christian; Freitas, Filomena; Reis, Maria A M

    2014-11-01

    Enterobacter A47 produces a fucose-containing exopolysaccharide (EPS) by cultivation in mineral medium supplemented with glycerol. EPS synthesis by Enterobacter A47 was shown to be influenced by both the initial glycerol and nitrogen concentrations and by the nutrients' feeding rate during the fed-batch phase. Initial nitrogen concentrations above 1.05g/L were detrimental for EPS synthesis: the productivity was reduced to 0.35-0.62g/Ld (compared to 1.89-2.04g/Ld under lower nitrogen concentrations) and the polymer had lower fucose content (14-17%mol, compared to 36-38%mol under lower nitrogen concentrations). On the other hand, EPS productivity was improved to 5.66g/Ld by increasing the glycerol and nitrogen feeding rates during the fed-batch phase. However, the EPS thus obtained had lower fucose (26%mol) and higher galactose (34%mol) contents, as well as lower average molecular weight (7.2×10(5)). The ability of Enterobacter A47 to synthesize EPS with different physico-chemical characteristics may be useful for the generation of biopolymers with distinct functional properties suitable for different applications. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Fermentative hydrogen production by the newly isolated Enterobacter asburiae SNU-1

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Jong-Hwan; Hyun Yoon, Jong; Eun Kyoung Ahn; Park, Tai Hyun [School of Chemical and Biological Engineering, Seoul National University, Seoul 151-744 (Korea); Kim, Mi-Sun [Biomass Research Team, Korea Institute of Energy Research, Daejeon 305-343 (Korea); Jun Sim, Sang [Department of Chemical Engineering, Sungkyunkwan University, Suwon 440-746 (Korea)

    2007-02-15

    A new fermentative hydrogen-producing bacterium was isolated from a domestic landfill and identified as Enterobacter asburiae using 16S rRNA gene sequencing and DNA-DNA hybridization methods. The isolated bacterium, designated as Enterobacter asburiae SNU-1, is a new species that has never been examined as a potential hydrogen-producing bacterium. This study examined the hydrogen-producing ability of Enterobacter asburiae SNU-1. During fermentation, the hydrogen was mainly produced in the stationary phase. The hydrogen yield based on the formate consumption was 0.43 mol hydrogen/mol formate. This strain was able to produce hydrogen over a wide range of pH (4-7.5), with the optimum pH being pH 7. The level of hydrogen production was also affected by the initial glucose concentration, and the optimum value was found to be 25 g glucose/l. The maximum and overall hydrogen productivities were 398 and 174 ml/l/hr, respectively, at pH 7 with an initial glucose concentration of 25 g/l. This strain could produce hydrogen from glucose and many other carbon sources such as fructose, sucrose, and sorbitol. (author)

  18. Molecular Characterization of the Plant Growth Promoting Bacterium Enterobacter sp. SA187 upon Contact with Arabidopsis thaliana

    KAUST Repository

    Alsharif, Wiam

    2018-01-01

    Salt stress is a severe environmental challenge in agriculture, limiting the quality and productivity of the crops around the globe. Plant growth promoting rhizobacteria (PGPR) is proposed as a friendly solution to overcome those challenges

  19. Draft genome sequences of six neonatal meningitis-causing escherichia coli isolates (SP-4, SP-5, SP-13, SP-16, SP-46, and SP-65)

    Science.gov (United States)

    Neonatal meningitis Escherichia coli isolates (SP-4, SP-5, SP-13, SP-16, SP-46, and SP-65) were recovered from infants in the Netherlands from 1989 to 1997. Here, we report the draft genome sequences for these six E. coli isolates, which are currently being used to validate food safety processing te...

  20. High frequency of silver resistance genes in invasive isolates of Enterobacter and Klebsiella species.

    Science.gov (United States)

    Sütterlin, S; Dahlö, M; Tellgren-Roth, C; Schaal, W; Melhus, Å

    2017-07-01

    Silver-based products have been marketed as an alternative to antibiotics, and their consumption has increased. Bacteria may, however, develop resistance to silver. To study the presence of genes encoding silver resistance (silE, silP, silS) over time in three clinically important Enterobacteriaceae genera. Using polymerase chain reaction (PCR), 752 bloodstream isolates from the years 1990-2010 were investigated. Age, gender, and ward of patients were registered, and the susceptibility to antibiotics and silver nitrate was tested. Clonality and single nucleotide polymorphism were assessed with repetitive element sequence-based PCR, multi-locus sequence typing, and whole-genome sequencing. Genes encoding silver resistance were detected most frequently in Enterobacter spp. (48%), followed by Klebsiella spp. (41%) and Escherichia coli 4%. Phenotypical resistance to silver nitrate was found in Enterobacter (13%) and Klebsiella (3%) isolates. The lowest carriage rate of sil genes was observed in blood isolates from the neonatology ward (24%), and the highest in blood isolates from the oncology/haematology wards (66%). Presence of sil genes was observed in international high-risk clones. Sequences of the sil and pco clusters indicated that a single mutational event in the silS gene could have caused the phenotypic resistance. Despite a restricted consumption of silver-based products in Swedish health care, silver resistance genes are widely represented in clinical isolates of Enterobacter and Klebsiella species. To avoid further selection and spread of silver-resistant bacteria with a high potential for healthcare-associated infections, the use of silver-based products needs to be controlled and the silver resistance monitored. Copyright © 2017 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  1. In vitro susceptibility and resistance phenotypes in contemporary Enterobacter isolates in a university hospital in Crete, Greece.

    Science.gov (United States)

    Maraki, Sofia; Vardakas, Konstantinos Z; Samonis, George; Perdikis, Dimitrios; Mavromanolaki, Viktoria Eirini; Kofteridis, Diamantis P; Falagas, Matthew E

    2017-06-01

    To study the evolution in the susceptibility of Enterobacter spp. in Crete, Greece from 2010 to 2015. Non-duplicate isolates were studied using automated systems. Phenotypic confirmatory tests were applied. A total of 939 Enterobacter isolates were included. Colistin was the most active antibiotic (97.9%) followed by imipenem (96.1%), gentamicin (95.7%), tigecycline (91.8%), cefepime (89.4%), chloramphenicol (85.8%), fosfomycin (85.5%), trimethoprim/sulfamethoxazole (83.3%) and piperacillin/tazobactam (73.3%). Antibiotic resistance did not increase during the study period for most antibiotics. Lower susceptibility was observed among multidrug-resistant strains and carbapenem-nonsusceptible isolates. AmpC was the most common resistant mechanism (21%); carbapenemases (3.7%) and aminoglycoside-modifying enzymes (6.5%) were also detected. A significant proportion of Enterobacter spp. was resistant to several antibiotics, most notably β-lactams.

  2. Detection of New Delhi Metallo-Beta-Lactamase (Encoded by blaNDM-1 ) in Enterobacter aerogenes in China.

    Science.gov (United States)

    Shen, Yong; Xiao, Wei-Qiang; Gong, Jiao-Mei; Pan, Jun; Xu, Qing-Xia

    2017-03-01

    The increase in bla NDM -1 in Enterobacteriaceae has become a major concern worldwide. In previous study, we investigated clonal dissemination and mechanisms of resistance to carbapenem in China. We carried out retrospective surveillance for bla NDM -1 among carbapenem-resistant enterobacter strains, which were isolated from patients at our hospital by bacterial strains selection, antimicrobial susceptibility testing, species identification, and molecular detection of resistance gene. We found three bla NDM -1 -positive isolates which were identified as Enterobacter aerogenes in clinical patients in China. The bla NDM -1 -positive Enterobacter aerogenes isolates were first found. It is important to mandate prudent usage of antibiotics and implement infection control measures to control the spread of these resistant bla NDM -1 -positive strains. © 2016 Wiley Periodicals, Inc.

  3. Aerobic and heterotrophic nitrogen removal by Enterobacter cloacae CF-S27 with efficient utilization of hydroxylamine.

    Science.gov (United States)

    Padhi, Soumesh Kumar; Tripathy, Swetaleena; Mohanty, Sriprakash; Maiti, Nikhil Kumar

    2017-05-01

    Heterotrophic bacterium, Enterobacter cloacae CF-S27 exhibited simultaneous nitrification and aerobic denitrification in presence of high concentration of hydroxylamine. With the initial nitrogen concentration of 100mgL -1 h -1 , ammonium, nitrate and nitrite removal efficiencies were 81%, 99.9% and 92.8%, while the corresponding maximum removal rates reached as high as 11.6, 15.1 and 11.2mgL -1 h -1 respectively. Quantitative amplification by real time PCR and enzyme assay demonstrated that hydroxylamine reductase gene (hao) is actively involved in hetrotrophic nitrification and aerobic denitrification process of Enterobacter cloacae CF-S27. PCR primers were designed targeting amplification of hao gene from diversified environmental soil DNA. The strain Enterobacter cloacae CF-S27 significantly maintained the undetectable amount of dissolved nitrogen throughout 60days of zero water exchange fish culture experiment in domestic wastewater. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Enterobacter sakazakii brain abscess in the neonate: the importance of neuroradiologic imaging

    International Nuclear Information System (INIS)

    Burdette, J.H.; Santos, C.

    2000-01-01

    Background. Enterobacter sakazakii is a rare but important cause of life-threatening neonatal sepsis and meningitis complicated by the development of brain abscess. Objective. Given the neurotropic qualities of this organism, early diagnosis and treatment are crucial as a poor prognosis follows brain abscess formation. Materials and methods. Cross-sectional imaging (CT and MRI) play an important role in the diagnostic work-up. Conclusion. A biopsy-proven case of E. sakazakii brain abscess, which was diagnosed on MR images, is presented, and the importance of prompt radiologic imaging of the central nervous system in the work-up of patients with this life-threatening disease is discussed. (orig.)

  5. Phenotypic and molecular characterization of antimicrobial resistance in Enterobacter spp. isolates from companion animals in Japan.

    Science.gov (United States)

    Harada, Kazuki; Shimizu, Takae; Mukai, Yujiro; Kuwajima, Ken; Sato, Tomomi; Kajino, Akari; Usui, Masaru; Tamura, Yutaka; Kimura, Yui; Miyamoto, Tadashi; Tsuyuki, Yuzo; Ohki, Asami; Kataoka, Yasushi

    2017-01-01

    The emergence of antimicrobial resistance among Enterobacter spp., including resistance to extended-spectrum cephalosporins (ESC), is of great concern in both human and veterinary medicine. In this study, we investigated the prevalence of antimicrobial resistance among 60 isolates of Enterobacter spp., including E. cloacae (n = 44), E. aerogenes (n = 10), and E. asburiae (n = 6), from clinical specimens of dogs and cats from 15 prefectures in Japan. Furthermore, we characterized the resistance mechanisms harbored by these isolates, including extended-spectrum β-lactamases (ESBLs) and plasmid-mediated quinolone resistance (PMQR); and assessed the genetic relatedness of ESC-resistant Enterobacter spp. strains by multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). Antimicrobial susceptibility testing demonstrated the resistance rates to ampicillin (93.3%), amoxicillin-clavulanic acid (93.3%), cefmetazole (93.3%), chloramphenicol (46.7%), ciprofloxacin (43.3%), tetracycline (40.0%), ceftazidime (33.3%), cefotaxime (33.3%), trimethoprim/sulfamethoxazole (28.3%), gentamicin (23.3%), and meropenem (0%). Phenotypic testing detected ESBLs in 16 of 18 ESC-resistant E. cloacae isolates but not in the other species. The most frequent ESBL was CTX-M-15 (n = 8), followed by SHV-12 (n = 7), and CTX-M-3 (n = 1). As for AmpC β-lactamases, CMY-2 (n = 2) and DHA-1 (n = 2) were identified in ESC-resistant E. cloacae strains with or without ESBLs. All of the ESC-resistant E. cloacae strains also harbored one or two PMQRs, including qnrB (n = 15), aac(6')-Ib-cr (n = 8), and qnrS (n = 2). Based on MLST and PFGE analysis, E. cloacae clones of ST591-SHV-12, ST171-CTX-M-15, and ST121-CTX-M-15 were detected in one or several hospitals. These results suggested intra- and inter-hospital dissemination of E. cloacae clones co-harboring ESBLs and PMQRs among companion animals. This is the first report on the large-scale monitoring of antimicrobial-resistant isolates

  6. Bioconversion of lutein by Enterobacter hormaechei to form a new compound, 8-methyl-α-ionone.

    Science.gov (United States)

    Zhong, Guifang; Wang, Fangfang; Sun, Jianhong; Ye, Jianbin; Mao, Duobin; Ma, Ke; Yang, Xuepeng

    2017-07-01

    To investigate the final product of the bioconversion of lutein by a novel lutein-degrading bacterium, Enterobacter hormaechei A20, and the kinetics of the process. A new product, 8-methyl-α-ionone, was resolved by GC-MS. The compound was further identified by NMR. A conversion yield of 90% was achieved by E. hormaechei in 36 h with 10 g lutein l -1 . This is the first report of the bioconversion of lutein to form 8-methyl-α-ionone. A degradation pathway is proposed.

  7. Chronological emergence of a class a carbapenemase-producing Enterobacter aerogenes in Taiwan

    Directory of Open Access Journals (Sweden)

    Zheng-Yi Huang

    2014-01-01

    Full Text Available This study reports the case of a 77-year-old, long-term, bedridden patient, with a nosocomial wound infection caused by a multidrug-resistant strain of Enterobacter aerogenes (E. aerogense. The isolate produced an Ambler-class A carbapenemase, which was demonstrated by the Modified Hodge test (MHT and a confirmatory inhibition test. However, no known carbapenemase genes were discovered in this isolate by polymerase chain reactions (PCRs with specific primers. New carbapenemase or other resistant mechanisms could be explored from the isolate of carbapenem-resistant E. aerogense, according to the revised criteria (CLSI, 2012.

  8. Infective endocarditis due to Enterobacter cloacae resistant to third- and fourth-generation cephalosporins.

    Science.gov (United States)

    Yoshino, Yusuke; Okugawa, Shu; Kimura, Satoshi; Makita, Eiko; Seo, Kazunori; Koga, Ichiro; Matsunaga, Naohisa; Kitazawa, Takatoshi; Ota, Yasuo

    2015-04-01

    We report the case of using a long-term combination of meropenem and amikacin to treat infective endocarditis caused by Enterobacter cloacae resistant to third- and fourth-generation cephalosporins. Multi-drug resistant Gram-negative bacilli, such as the E. cloacae in our study, may become possible pathogens of infective endocarditis. Our experience with this case indicates that long-term use of a combination of β-lactam and aminoglycosides might represent a suitable management option for future infective endocarditis cases due to non-Haemophilus, Actinobacillus, Cardiobacterium, Eikenella, Kingella spp. (HACEK group) Gram-negative bacilli such as ours. Copyright © 2012. Published by Elsevier B.V.

  9. Molecular identification of aiiA homologous gene from endophytic Enterobacter species and in silico analysis of putative tertiary structure of AHL-lactonase.

    Science.gov (United States)

    Rajesh, P S; Rai, V Ravishankar

    2014-01-03

    The aiiA homologous gene known to encode AHL- lactonase enzyme which hydrolyze the N-acylhomoserine lactone (AHL) quorum sensing signaling molecules produced by Gram negative bacteria. In this study, the degradation of AHL molecules was determined by cell-free lysate of endophytic Enterobacter species. The percentage of quorum quenching was confirmed and quantified by HPLC method (pEnterobacter asburiae VT65, Enterobacter aerogenes VT66 and Enterobacter ludwigii VT70 strains. Sequence alignment analysis revealed the presence of two zinc binding sites, "HXHXDH" motif as well as tyrosine residue at the position 194. Based on known template available at Swiss-Model, putative tertiary structure of AHL-lactonase was constructed. The result showed that novel endophytic strains of Enterobacter genera encode the novel aiiA homologous gene and its structural importance for future study. Copyright © 2013 Elsevier Inc. All rights reserved.

  10. Hybrid modeling of microbial exopolysaccharide (EPS) production: The case of Enterobacter A47.

    Science.gov (United States)

    Marques, Rodolfo; von Stosch, Moritz; Portela, Rui M C; Torres, Cristiana A V; Antunes, Sílvia; Freitas, Filomena; Reis, Maria A M; Oliveira, Rui

    2017-03-20

    Enterobacter A47 is a bacterium that produces high amounts of a fucose-rich exopolysaccharide (EPS) from glycerol residue of the biodiesel industry. The fed-batch process is characterized by complex non-linear dynamics with highly viscous pseudo-plastic rheology due to the accumulation of EPS in the culture medium. In this paper, we study hybrid modeling as a methodology to increase the predictive power of models for EPS production optimization. We compare six hybrid structures that explore different levels of knowledge-based and machine-learning model components. Knowledge-based components consist of macroscopic material balances, Monod type kinetics, cardinal temperature and pH (CTP) dependency and power-law viscosity models. Unknown dependencies are set to be identified by a feedforward artificial neural network (ANN). A semiparametric identification schema is applied resorting to a data set of 13 independent fed-batch experiments. A parsimonious hybrid model was identified that describes the dynamics of the 13 experiments with the same parameterization. The final model is specific to Enterobacter A47 but can be easily extended to other microbial EPS processes. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Genome analysis and identification of gelatinase encoded gene in Enterobacter aerogenes

    Science.gov (United States)

    Shahimi, Safiyyah; Mutalib, Sahilah Abdul; Khalid, Rozida Abdul; Repin, Rul Aisyah Mat; Lamri, Mohd Fadly; Bakar, Mohd Faizal Abu; Isa, Mohd Noor Mat

    2016-11-01

    In this study, bioinformatic analysis towards genome sequence of E. aerogenes was done to determine gene encoded for gelatinase. Enterobacter aerogenes was isolated from hot spring water and gelatinase species-specific bacterium to porcine and fish gelatin. This bacterium offers the possibility of enzymes production which is specific to both species gelatine, respectively. Enterobacter aerogenes was partially genome sequenced resulting in 5.0 mega basepair (Mbp) total size of sequence. From pre-process pipeline, 87.6 Mbp of total reads, 68.8 Mbp of total high quality reads and 78.58 percent of high quality percentage was determined. Genome assembly produced 120 contigs with 67.5% of contigs over 1 kilo base pair (kbp), 124856 bp of N50 contig length and 55.17 % of GC base content percentage. About 4705 protein gene was identified from protein prediction analysis. Two candidate genes selected have highest similarity identity percentage against gelatinase enzyme available in Swiss-Prot and NCBI online database. They were NODE_9_length_26866_cov_148.013245_12 containing 1029 base pair (bp) sequence with 342 amino acid sequence and NODE_24_length_155103_cov_177.082458_62 which containing 717 bp sequence with 238 amino acid sequence, respectively. Thus, two paired of primers (forward and reverse) were designed, based on the open reading frame (ORF) of selected genes. Genome analysis of E. aerogenes resulting genes encoded gelatinase were identified.

  12. Occurrence of Enterobacter hormaechei carrying blaNDM-1 and blaKPC-2 in China.

    Science.gov (United States)

    Yang, Biwei; Feng, Yu; McNally, Alan; Zong, Zhiyong

    2018-02-01

    Three carbapenem-resistant clinical isolates of the Enterobacter cloacae complex (ECC) were recovered from different patients in a hospital. All 3 isolates carried 2 carbapenemase genes bla KPC-2 and bla NDM-1 . A study was performed to characterize their relatedness and to investigate possible links among the patients. Whole genome sequencing revealed that the isolates were Enterobacter hormaechei and belonged to ST177 of the ECC. There were 19-142 single nucleotide polymorphisms (SNPs) between the isolates, suggesting that the isolates were likely from a central reservoir, which might have existed for some time. bla KPC-2 and bla NDM-1 were carried on 2 different IncF-type plasmids in the isolates. The 3 bla NDM-1 -carrying plasmids were almost identical and were self-transmissible, while the bla KPC-2 -carrying plasmids were only transmissible in the presence of the bla NDM-1 -carrying plasmid. The source of and direct links among them were not identified, suggesting a hospital transmission of a common multidrug resistant strain. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Molecular cloning and expression of a novel trehalose synthase gene from Enterobacter hormaechei

    Directory of Open Access Journals (Sweden)

    Yue Ming

    2009-06-01

    Full Text Available Abstract Background Trehalose synthase (TreS which converts maltose to trehalose is considered to be a potential biocatalyst for trehalose production. This enzymatic process has the advantage of simple reaction and employs an inexpensive substrate. Therefore, new TreS producing bacteria with suitable enzyme properties are expected to be isolated from extreme environment. Results Six TreS producing strains were isolated from a specimen obtained from soil of the Tibetan Plateau using degenerate PCR. A novel treS gene from Enterobacter hormaechei was amplified using thermal asymmetric interlaced PCR. The gene contained a 1626 bp open reading frame encoding 541 amino acids. The gene was expressed in Escherichia coli, and the recombinant TreS was purified and characterized. The purified TreS had a molecular mass of 65 kDa and an activity of 18.5 U/mg. The optimum temperature and pH for the converting reaction were 37°C and 6, respectively. Hg2+, Zn2+, Cu2+and SDS inhibited the enzyme activity at different levels whereas Mn2+ showed an enhancing effect by 10%. Conclusion In this study, several TreS producing strains were screened from a source of soil bacteria. The characterization of the recombinant TreS of Enterobacter hormaechei suggested its potential application. Consequently, a strategy for isolation of TreS producing strains and cloning of novel treS genes from natural sources was demonstrated.

  14. Evidence supporting dissimilatory and assimilatory lignin degradation in Enterobacter lignolyticus SCF1

    Directory of Open Access Journals (Sweden)

    Kristen M DeAngelis

    2013-09-01

    Full Text Available The anaerobic isolate Enterobacter lignolyticus SCF1 was initially cultivated based on anaerobic growth on lignin as sole carbon source. The source of the isolated bacteria was from tropical forest soils that decompose litter rapidly with low and fluctuating redox potentials, making it likely that bacteria using oxygen-independent enzymes play an important role in decomposition. We have used transcriptomics and proteomics to examine the increased growth of the anaerobic isolate Enterobacter lignolyticus SCF1 when grown on media amended with lignin compared to unamended growth. Proteomics revealed accelerated xylose uptake and metabolism under lignin-amended growth, and lignin degradation via the 4-hydroxyphenylacetate degradation pathway, catalase/peroxidase enzymes, and the glutathione biosynthesis and glutathione S-transferase proteins. We also observed increased production of NADH-quinone oxidoreductase, other electron transport chain proteins, and ATP synthase and ATP-binding cassette (ABC transporters. We detected significant lignin degradation over time by absorbance, and also used metabolomics to demonstrate increased xylose utilization in lignin-amended compared to unamended growth. Our data shows the advantages of a multi-omics approach, where incomplete pathways identified by genomics were completed, and new observations made on coping with poor carbon availability. The fast growth, high efficiency and specificity of enzymes employed in bacterial anaerobic litter deconstruction makes these soils useful templates for improving biofuel production.

  15. Multiple brain abscesses due to Enterobacter cloacae in an immune-competent child

    Directory of Open Access Journals (Sweden)

    Arushi G. Saini

    2017-09-01

    Full Text Available Brain abscesses due to Enterobacteriaceae in immune-competent children are rare, and those due to Enterobacter cloacae are even rarer. We report an interesting case of community-acquired E. cloacae neuroinfection resulting in multiple brain abscesses in a young child with no underlying risk-factors. A 10 year-old-boy presented with low-grade fever, headache, neck pain and progressive deterioration of sensorium. On examination, he was conscious but drowsy with photophobia, normal fundii, meningeal signs, mild hypertonia, brisk muscle stretch reflexes and extensor plantar responses. Magnetic resonance imaging of brain showed bilateral, multiple pyogenic abscesses. Culture of the abscess material aspirated at the time of surgical drainage showed growth of E. cloacae. He received intravenous imipenem for 18 weeks guided by clinical and radiological response. A pragmatic approach combining early surgical drainage, targeted antimicrobial therapy and patient-tailored duration based on the clinico-radiological response is needed in such difficult cases. Keywords: Neuroinfection, Enterobacter, Brain abscess, Pyogenic, Carbapenems

  16. Production of L-lactic acid from metabolically engineered strain of Enterobacter aerogenes ATCC 29007.

    Science.gov (United States)

    Thapa, Laxmi Prasad; Lee, Sang Jun; Park, Chulhwan; Kim, Seung Wook

    2017-07-01

    In this study, L-lactic acid production was investigated from metabolically engineered strain of E. aerogenes ATCC 29007. The engineered strain E. aerogenes SUMI01 (Δpta) was generated by the deletion of phosphate acetyltransferase (pta) gene from the chromosome of E. aerogenes ATCC 29007 and deletion was confirmed by colony PCR. Under the optimized fermentation conditions, at 37°C and pH 6 for 84h, the L-lactic acid produced by engineered strain E. aerogenes SUMI01 (Δpta) in flask fermentation using 100g/L mannitol as the carbon source was 40.05g/L as compared to that of the wild type counterpart 20.70g/L. At the end of the batch fermentation in bioreactor the production of L-lactic acid reached to 46.02g/L and yield was 0.41g/g by utilizing 112.32g/L mannitol. This is the first report regarding the production of L-lactic acid from Enterobacter species. We believe that this result may provide valuable guidelines for further engineering Enterobacter strain for the improvement of L-lactic acid production. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Evidence supporting dissimilatory and assimilatory lignin degradation in Enterobacter lignolyticus SCF1

    Energy Technology Data Exchange (ETDEWEB)

    DeAngelis, Kristen M.; Sharma, Deepak; Varney, Rebecca; Simmons, Blake A.; Isern, Nancy G.; Markillie, Lye Meng; Nicora, Carrie D.; Norbeck, Angela D.; Taylor, Ronald C.; Aldrich, Joshua T.; Robinson, Errol W.

    2013-08-29

    The anaerobic isolate Enterobacter lignolyticus SCF1 was initially cultivated based on anaerobic growth on lignin as sole carbon source. The source of the isolated bacteria was from tropical forest soils that decompose litter rapidly with low and fluctuating redox potentials, making it likely that bacteria using oxygen-independent enzymes play an important role in decomposition. We have examined differential expression of the anaerobic isolate Enterobacter lignolyticus SCF1 during growth on lignin. After 48 hours of growth, we used transcriptomics and proteomics to define the enzymes and other regulatory machinery that these organisms use to degrade lignin, as well as metabolomics to measure lignin degradation and monitor the use of lignin and iron as terminal electron acceptors that facilitate more efficient use of carbon. Proteomics revealed accelerated xylose uptake and metabolism under lignin-amended growth, and lignin degradation via the 4-hydroxyphenylacetate degradation pathway, catalase/peroxidase enzymes, and the glutathione biosynthesis and glutathione S-transferase proteins. We also observed increased production of NADH-quinone oxidoreductase, other electron transport chain proteins, and ATP synthase and ATP-binding cassette (ABC) transporters. Our data shows the advantages of a multi-omics approach, where incomplete pathways identified by genomics were completed, and new observations made on coping with poor carbon availability. The fast growth, high efficiency and specificity of enzymes employed in bacterial anaerobic litter deconstruction makes these soils useful templates for improving biofuel production.

  18. Characterization of the population structure, drug resistance mechanisms and plasmids of the community-associated Enterobacter cloacae complex in China

    NARCIS (Netherlands)

    Zhou, Kai; Yu, Wei; Cao, Xiaoli; Shen, Ping; Lu, Haifeng; Luo, Qixia; Rossen, John W. A.; Xiao, Yonghong

    Objectives: To investigate the population structure, drug resistance mechanisms and plasmids of community-associated Enterobacter cloacae complex (CA-ECC) isolates in China. Methods: Sixty-two CA-ECC isolates collected from 31 hospitals across China were typed by hsp60 typing and MLST. ESBL and

  19. Association of Enterobacter cloacae and other bacteria with onion bulb rot in the Columbia Basin of Washington and Oregon, USA

    Science.gov (United States)

    Approximately 1.6 million metric tons of onion bulbs are produced annually in the Pacific Northwest USA. Bulb decay can be a major problem and is caused by a variety of plant pathogens. Onion bulbs exhibiting symptoms of bacterial rot were sampled to determine the causal agents. Enterobacter cloacae...

  20. Method for phenotypic detection of extended-spectrum beta-lactamases in enterobacter species in the routine clinical setting

    NARCIS (Netherlands)

    Stuart, J.C.; Diederen, B.; Al Naiemi, N.; Fluit, A.; Arents, N.; Thijsen, S.; Vlaminckx, B.; Mouton, J.W.; Leverstein-van Hall, M.

    2011-01-01

    In 271 Enterobacter blood culture isolates from 12 hospitals, extended-spectrum beta-lactamase (ESBL) prevalence varied between 0% and 30% per hospital. High prevalence was associated with dissemination, indicating the potential relevance of infection control measures. Screening with cefepime or

  1. New record of Pterotaenia fasciata (Wiedemann (Diptera, Ulidiidae in Brazil, a probably mechanical vector of enteric bacteria Novo registro de Pterotaenia fasciata (Wiedemann (Diptera, Ulidiidae no Brasil, um provável vetor mecânico de enterobactérias

    Directory of Open Access Journals (Sweden)

    Anderson Sena Barnabe

    2007-03-01

    Full Text Available Pterotaenia fasciata is commonly recorded in rural areas in Argentina, but during a Diptera survey study developed in a reservoir which retains storm water from polluted canals in an urban area of Taboão da Serra municipality, SP, Brazil, we could capture P. fasciata adults. Enteric bacteria Escherichia coli T. Escherich, 1885 and Proteus sp. were isolated from P. fasciata collected in traps inside the reservoir and around it. Fecal coliforms and E. coli were found in the water of the reservoir. These records suggest that a high abundance of this species at urban areas with inadequate sewage canals should reveal these muscoid dipterans as mechanical vectors of enteric bacteria.Pterotaenia fasciata é encontrada freqüentemente em áreas rurais na Argentina, mas durante um estudo de levantamento de Diptera em um reservatório de retenção de enchentes em uma área urbana do município de Taboão da Serra, SP, Brasil, foram capturados adultos de P. fasciata. As enterobactérias Escherichia coli T. Escherich, 1885 e Proteus sp. foram isoladas de P. fasciata coletada em armadilhas no reservatório e em seu entorno. Coliformes fecais e E. coli foram encontrados na água do reservatório. Esses registros sugerem que a alta abundância dessa espécie em áreas urbanas sem saneamento básico poderia indicar esses dípteros muscóides como vetores mecânicos de enterobactérias.

  2. Detection of extended-spectrum β-lactamase in Enterobacter spp.--evaluation of six phenotypic tests.

    Science.gov (United States)

    Nogueira-Miranda, Keite da Silva; Palmeiro, Jussara Kasuko; Conte, Danieli; Maia, Fernanda Valverde; Reason, Iara Taborda de Messias; Monteiro, Cristina Leise; Dalla-Costa, Libera Maria

    2012-02-01

    Extended-spectrum β-lactamases (ESBL) are plasmid-mediated enzymes that hydrolyze cephalosporins and monobactams. The lack of a standard method to detect ESBL in Enterobacter spp. has led to underestimating its frequency. The aim of this study was to evaluate ESBL detection in Enterobacter spp. By the double-disk synergy test (DDST) and combined disk test (CDT) assay using cefepime, cefotaxime, and ceftazime as substrates for ESBL, plus AmpC inhibitors in different associations. A total of 83 Enterobacter spp. ESBL and 31 non-ESBL Enterobacter spp. were tested, and a cutoff point ≥3 mm was defined using a receiver operating characteristic (ROC) curve for combined disc methods. All tests showed 100% specificity. The sensitivity was 89.2% for DDST and CDT without AmpC inibitor, 90.4% in the combined disc test in Mueller-Hinton agar containing phenylboronic acid (CDT-PBAA), and 94% in the combined disc test in Mueller-Hinton agar containing cloxacillin (CDT-CLXA). Cefepime was the best substrate, mainly when AmpC inhibitors were not used. However, superior results were achieved when all cephalosporins were evaluated together. In conclusion, to improve ESBL detection in Enterobacter spp., some modifications in phenotypic tests are needed, such as to reduce the distance between the discs to 20 mm in DDST, to use a cutoff point for ≥3 mm on the CDT, and to include a cefepime disk or an inhibitor of AmpC in all tests.

  3. Whole genome sequence of Enterobacter ludwigii type strain EN-119T, isolated from clinical specimens.

    Science.gov (United States)

    Li, Gengmi; Hu, Zonghai; Zeng, Ping; Zhu, Bing; Wu, Lijuan

    2015-04-01

    Enterobacter ludwigii strain EN-119(T) is the type strain of E. ludwigii, which belongs to the E. cloacae complex (Ecc). This strain was first reported and nominated in 2005 and later been found in many hospitals. In this paper, the whole genome sequencing of this strain was carried out. The total genome size of EN-119(T) is 4952,770 bp with 4578 coding sequences, 88 tRNAs and 10 rRNAs. The genome sequence of EN-119(T) is the first whole genome sequence of E. ludwigii, which will further our understanding of Ecc. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  4. Effect of He-Ne laser irradiation on hydrogen production by Enterobacter aerogenes

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Wenyu; Wen, Jianping; Jia, Xiaoqiang; Sun, Bing; Chen, Yu.; Liu, Minhui [Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China)

    2008-01-15

    Enterobacter aerogenes W-23 bacteria exhibiting hydrogen production (HP) ability were exposed to He-Ne laser irradiation (632.8 nm) to improve the HP ability. Upon the optimum irradiation dosage (18 mW for 22.2 min), a stable positive mutant strain E. aerogenes HB-5M was obtained. The maximum specific rate of HP of the mutant strain was 0.042h{sup -1}, which was about twice that of the wild strain. It was suggested that the higher HP ability of the mutant strain might be presumably attributed to the enhancement of hydrogenase activity. In addition, the kinetic parameters of cell growth, substrate consumption and HP of the wild strain and its mutant strain were regressed to simulate the fermentation process of E. aerogenes. The simulated results agreed well with the experimental data. (author)

  5. Enterobacter asburiae KUNi5, a Nickel Resistant Bacterium for Possible Bioremediation of Nickel Contaminated Sites.

    Science.gov (United States)

    Paul, Anirudha; Mukherjee, Samir Kumar

    2016-01-01

    Nickel resistant bacterial strain Enterobacter asburiae KUNi5 was isolated and showed resistance up to 15 mM and could remove Ni optimally better at 37 degrees C and pH 7. Maximum removal was found at initial concentration of 0.5 to 2 mM, however, growth and Ni removal were affected by other heavy metals. Major amount of the metal was accumulated in the membrane fractions and certain negatively charged groups were found responsible for Ni binding. KUNi5 could also produce 1-aminocyclopropane-1-carboxylate deaminase, indole-acetic acid and siderophore. It seems that KUNi5 could be a possible candidate for Ni detoxification and plant growth promotion in Ni-contaminated field.

  6. Inhibitory effects of bovine lactoferrin and lactoferricin B on Enterobacter sakazakii.

    Science.gov (United States)

    Wakabayashi, Hiroyuki; Yamauchi, Koji; Takase, Mitsunori

    2008-03-01

    The susceptibility of Enterobacter sakazakii, a food-borne pathogen, to several metal-bound forms of bovine lactoferrin (LF), pepsin-hydrolyzed LF (LF-hyd), and LF-derived peptide lactoferricin B (LFcin B) was tested. MIC and MBC testing revealed that 4 strains of E. sakazakii show susceptibility to apo- and Cu-LF, LF-hyd, and LFcin B, but not to Fe-LF, similarly to Escherichia coli. A growth curve test indicated that E. sakazakii was inhibited in a dose-dependent manner by apo-LF at 0.5 to 8 mg/ml. Even after being heated at 80 degrees C, LF at above 1 mg/ml inhibited the bacterial growth. These results suggest that bovine LF-related compounds may be useful for the inhibition of E. sakazakii in foods.

  7. Nosocomial outbreak of Enterobacter gergoviae bacteraemia in a neonatal intensive care unit.

    Science.gov (United States)

    Ganeswire, R; Thong, K L; Puthucheary, S D

    2003-04-01

    A nosocomial outbreak of bacteraemia, caused by Enterobacter gergoviae infected 11 babies, nine of whom were premature, and was investigated in the neonatal intensive care unit (NICU) of a general hospital in Johor Bahru, Malaysia. The strain that was isolated from the babies was also isolated from the dextrose saline used for the dilution of parenteral antibiotics and from the hands of a healthcare worker on duty in the nursery. Pulsed-field gel electrophoresis (PFGE) of Xba I-digested chromosomal DNA confirmed a possible cross-contamination of parenteral dextrose saline and the healthcare worker. Prompt and effective control measures were initiated within NICU and the nosocomial infection of E. gergoviae was brought to an abrupt end. To the best of our knowledge, this is the first documented outbreak of E. gergoviae in the NICU in a hospital in the state of Johor, Malaysia.

  8. Enhanced dark hydrogen fermentation by addition of ferric oxide nanoparticles using Enterobacter aerogenes.

    Science.gov (United States)

    Lin, Richen; Cheng, Jun; Ding, Lingkan; Song, Wenlu; Liu, Min; Zhou, Junhu; Cen, Kefa

    2016-05-01

    Ferric oxide nanoparticles (FONPs) were used to facilitate dark hydrogen fermentation using Enterobacter aerogenes. The hydrogen yield of glucose increased from 164.5±2.29 to 192.4±1.14mL/g when FONPs concentration increased from 0 to 200mg/L. SEM images of E. aerogenes demonstrated the existence of bacterial nanowire among cells, suggesting FONPs served as electron conduits to enhance electron transfer. TEM showed cellular internalization of FONPs, indicating hydrogenase synthesis and activity was potentially promoted due to the released iron element. When further increasing FONPs concentration to 400mg/L, the hydrogen yield of glucose decreased to 147.2±2.54mL/g. Soluble metabolic products revealed FONPs enhanced acetate pathway of hydrogen production, but weakened ethanol pathway. This shift of metabolic pathways allowed more nicotinamide adenine dinucleotide for reducing proton to hydrogen. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Biotransformation of ferulic acid to 4-vinylguaiacol by Enterobacter soli and E. aerogenes.

    Science.gov (United States)

    Hunter, William J; Manter, Daniel K; van der Lelie, Daniel

    2012-12-01

    We investigated the conversion of ferulic acid to 4-vinylguaiacol (4-VG), vanillin, vanillyl alcohol, and vanillic acid by five Enterobacter strains. These high-value chemicals are usually synthesized by chemical methods but biological synthesis adds market value. Ferulic acid, a relatively inexpensive component of agricultural crops, is plentiful in corn hulls, cereal bran, and sugar-beet pulp. Two Enterobacter strains, E. soli, and E. aerogenes, accumulated 550-600 ppm amounts of 4-VG when grown in media containing 1,000 ppm ferulic acid; no accumulations were observed with the other strains. Decreasing the amount of ferulic acid present in the media increased the conversion efficiency. When ferulic acid was supplied in 500, 250, or 125 ppm amounts E. aerogenes converted ~72 % of the ferulic acid present to 4-VG while E. soli converted ~100 % of the ferulic acid to 4-VG when supplied with 250 or 125 ppm amounts of ferulic acid. Also, lowering the pH improved the conversion efficiency. At pH 5.0 E. aerogenes converted ~84 % and E. soli converted ~100 % of 1,000 ppm ferulic acid to 4-VG. Only small, 1-5 ppm, accumulations of vanillin, vanillyl alcohol, and vanillic acid were observed. E. soli has a putative phenolic acid decarboxylase (PAD) that is 168 amino acids long and is similar to PADs in other enterobacteriales; this protein is likely involved in the bioconversion of ferulic acid to 4-VG. E. soli or E. aerogenes might be useful as a means of biotransforming ferulic acid to 4-VG.

  10. Effect of some environmental parameters on fermentative hydrogen production by Enterobacter cloacae DM11

    Energy Technology Data Exchange (ETDEWEB)

    Nath, K.; Kumar, A.; Das, D. [Indian Inst. of Technology, Kharagpur (India). Dept. of Biotechnology, Fermentation Technology Laboratory

    2006-06-15

    This study addressed the issue of using biological systems for hydrogen production as an environmentally sound alternative to conventional thermochemical and electrochemical processes. In particular, it examined the potential for anaerobic fermentation for biological hydrogen production and the possibility of coupling gaseous energy generation with simultaneous treatment of biodegradable waste materials. The study focused on hydrogen production by anaerobic fermentation using Enterobacter cloacae DM11, a Gram-negative, motile facultative anaerobe. Although hydrogen production by these bacteria depends on many environmental parameters, there is very little information on the effects of these factors in the hydrogen production potential of this organism. For that reason, this study examined the effect of initial medium pH, reaction temperature, initial glucose concentration, and iron (Fe2+) concentration on the fermentative production of hydrogen. Fermentative hydrogen production was carried out by Enterobacter cloacae DM11, using glucose as the substrate. Batch cultivations were performed in a 500 ml custom-designed vertical tubular bioreactor. The maximum molar yield of hydrogen was 3.31 mol (mol glucose){sub 1}. The rate and cumulative volume of hydrogen production decreased at higher initial glucose concentration. The pH of 6.5 at a temperature of 37 degrees C was most suitable for maximum rate of production of hydrogen in batch fermentation. The addition of Fe2+ on hydrogen production had a marginal enhancing effect on total hydrogen production. A simple model developed from the modified Gompertz equation was used to fit the cumulative hydrogen production curve and to estimate the hydrogen production potential, maximum production rate, and lag time. It was concluded that these study results could be used in the development of a high rate continuous hydrogen production process. 30 refs., 4 tabs., 3 figs.

  11. ExaSP2

    Energy Technology Data Exchange (ETDEWEB)

    2017-09-08

    ExaSP2 is a reference implementation of typical linear algebra algorithms and workloads for a quantum molecular dynamics (QMD) electronic structure code. The algorithm is based on a recursive second-order Fermi-Operator expansion method (SP2) and is tailored for density functional based tight-binding calculations of material systems.

  12. NDM-1 encoded by a pNDM-HN380-like plasmid pNDM-BJ03 in clinical Enterobacter cloacae.

    Science.gov (United States)

    Lü, Yang; Liu, Wei; Liang, Hui; Zhao, Shulong; Zhang, Wei; Liu, Jia; Jin, Cheng; Hu, Hongyan

    2018-02-01

    A carbapenemase-producing Enterobacter cloacae hhy03 with a bla NDM-1 and bla SHV-12 -coharboring plasmid was isolated from a sputum specimen of a patient. This is the third nucleotide sequence report of bla NDM-1 -harboring plasmid from Enterobacter cloacae that have caused lethal infections in China, indicating the spread of NDM-1 by IncX3 plasmid between Enterobacteriaceae. Copyright © 2017. Published by Elsevier Inc.

  13. Emergence of extended-spectrum β-lactamase producing Enterobacter spp. in patients with bacteremia in a tertiary hospital in southern Brazil.

    Science.gov (United States)

    Nogueira, Keite da Silva; Paganini, Maria Cristina; Conte, Andréia; Cogo, Laura Lúcia; Taborda de Messias Reason, Iara; da Silva, Márcio José; Dalla-Costa, Libera Maria

    2014-02-01

    Extended-spectrum β-lactamases (ESBLs) are increasingly prevalent in Enterobacter spp., posing a challenge to the treatment of infections caused by this microorganism. The purpose of this retrospective study was to evaluate the prevalence, risk factors, and clinical outcomes of inpatients with bacteremia caused by ESBL and non ESBL-producing Enterobacter spp. in a tertiary hospital over the period 2004-2008. The presence of blaCTX-M, blaTEM, blaSHV, and blaPER genes was detected by polymerase chain reaction (PCR) and nucleotide sequence analysis. Genetic similarity between strains was defined by pulsed-field gel electrophoresis (PFGE). Enterobacter spp. was identified in 205 of 4907 of the patients who had positive blood cultures during hospitalization. Of those cases, 41 (20%) were ESBL-producing Enterobacter spp. Nosocomial pneumonia was the main source of bacteremia caused by ESBL-producing Enterobacter spp. The presence of this microorganism was associated with longer hospital stays. The ESBL genes detected were: CTX-M-2 (23), CTX-M-59 (10), CTX-M-15 (1), SHV-12 (5), and PER-2 (2). While Enterobacter aerogenes strains showed mainly a clonal profile, Enterobacter cloacae strains were polyclonal. Although no difference in clinical outcomes was observed between patients with infections by ESBL-producing and non-ESBL-producing strains, the detection of ESBL in Enterobacter spp. resulted in the change of antimicrobials in 75% of cases, having important implications in the decision-making regarding adequate antimicrobial therapy. Copyright © 2012 Elsevier España, S.L. All rights reserved.

  14. Risk factors and treatment outcomes of bloodstream infection caused by extended-spectrum cephalosporin-resistant Enterobacter species in adults with cancer.

    Science.gov (United States)

    Huh, Kyungmin; Kang, Cheol-In; Kim, Jungok; Cho, Sun Young; Ha, Young Eun; Joo, Eun-Jeong; Chung, Doo Ryeon; Lee, Nam Yong; Peck, Kyong Ran; Song, Jae-Hoon

    2014-02-01

    Treatment of Enterobacter infection is complicated due to its intrinsic resistance to cephalosporins. Medical records of 192 adults with cancer who had Enterobacter bacteremia were analyzed retrospectively to evaluate the risk factors for and the treatment outcomes in extended-spectrum cephalosporin (ESC)-resistant Enterobacter bacteremia in adults with cancer. The main outcome measure was 30-day mortality. Of the 192 patients, 53 (27.6%) had bloodstream infections caused by ESC-resistant Enterobacter species. Recent use of a third-generation cephalosporin, older age, tumor progression at last evaluation, recent surgery, and nosocomial acquisition were associated with ESC-resistant Enterobacter bacteremia. The 30-day mortality rate was significantly higher in the resistant group. Multivariate analysis showed that respiratory tract infection, tumor progression, septic shock at presentation, Enterobacter aerogenes as the culprit pathogen, and diabetes mellitus were independent risk factors for mortality. ESC resistance was significantly associated with mortality in patients with E. aerogenes bacteremia, although not in the overall patient population. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. My 40-Year History with Cronobacter/Enterobacter sakazakii – Lessons Learned, Myths Debunked, and Recommendations

    Science.gov (United States)

    Farmer, John J.

    2015-01-01

    Much has been learned about organism in the Cronobacter/Enterobacter sakazakii complex since I first named and described Enterobacter sakazakii in 1980. However, there are still wide knowledge gaps. One of the most serious is that are still many uncertainties associated with assessing the public health risk posed by these bacteria, particularly in neonatal meningitis. Over the last few decades, Cronobacter contamination of commercial powdered infant formula products has apparently been reduced, but it is still an ongoing problem. The powdered infant formula industry still cannot produce powdered formula that is free of bacterial contamination with Cronobacter, other Enterobacteriaceae, other pathogenic bacteria, and other microorganisms. Until this happens, infants and other will be at risk of becoming infected when they ingest contaminated formula. PMID:26640778

  16. Effectiveness of Disinfectants in Killing Enterobacter sakazakii in Suspension, Dried on the Surface of Stainless Steel, and in a Biofilm▿

    OpenAIRE

    Kim, Hoikyung; Ryu, Jee-Hoon; Beuchat, Larry R.

    2006-01-01

    The effectiveness of 13 disinfectants used in hospitals, day-care centers, and food service kitchens in killing Enterobacter sakazakii in suspension, dried on the surface of stainless steel, and in biofilm was determined. E. sakazakii exhibited various levels of resistance to the disinfectants, depending on the composition of the disinfectants, amount and type of organic matrix surrounding cells, and exposure time. Populations of planktonic cells suspended in water (7.22 to 7.40 log CFU/ml) d...

  17. Isolation and determination antimicrobial susceptibility pattern of Enterobacter cloacae strains isolated from consumed powdered infant formula milk in NICU ward

    Directory of Open Access Journals (Sweden)

    Jalal Mardaneh

    2014-11-01

    Full Text Available Background: Enterobacter cloacae is a rod-shaped, gram-negative bacillus, from the family of Enterobacteriaceae. It is an opportunistic pathogen and causes disease in plants and humans (premature and immunocompromised persons of all age groups. The goal of this study was to isolate and determine antimicrobial susceptibility pattern of Enterobacter cloacae strains isolated from consumed powdered infant formula (PIF milk in Neonatal Intensive Care Unit (NICU ward. Material and Methods: In this cross-sectional study, a total of 125 consumed powdered infant formula milk in NICU ward were surveyed. Isolation and Identification of microorganisms was carried out according to FDA method. Antimicrobial susceptibility test was performed using the standard disc diffusion method based on CLSI (2011 recommendations. Results: Enterobacter cloacae was isolated from 2 (1.6% of 125 PIF milk samples. The results showed that isolated strains are sensitive to most antibiotics. All isolates were resistant to amoxicillin. Conclusion: Since the infant formula (PIF samples are unsterile products and contamination could occure during different steps, it is imperative to prepare the infant formula milk foods according to the manufacturer’s instruction and in an aseptic condition. Contamination of PIF only could be reduced or prevented by monitoring the critical control points and taking appropriate action during the processing.

  18. Stimulation of the growth of Jatropha curcas by the plant growth promoting bacterium Enterobacter cancerogenus MSA2.

    Science.gov (United States)

    Jha, Chaitanya Kumar; Patel, Baldev; Saraf, Meenu

    2012-03-01

    A novel Enterobacter cancerogenus MSA2 is a plant growth promoting gamma-proteobacterium that was isolated from the rhizosphere of Jatropha cucas a potentially important biofuel feed stock plant. Based on phenotypic, physiological, biochemical and phylogenetic studies, strain MSA2 could be classified as a member of E. cancerogenus. However, comparisons of characteristics with other known species of the genus Enterobacter suggested that strain MSA2 could be a novel PGPB strain. In vitro studies were carried for the plant growth promoting attribute of this culture. It tested positive for ACC (1-aminocyclopropane-1-carboxylic acid) deaminase production, phytase, phosphate solubilization, IAA (Indole acetic acid) production, siderophore, and ammonia production. The isolate was then used as a inoculant for the vegetative study of Jatropha curcas plant. Enterobacter cancerogenus MSA2 supplemented with 1% carboxymethylcellulose showed overall plant growth promotion effect resulting in enhanced root length (124.14%), fresh root mass (81%), fresh shoot mass (120.02%), dry root mass (124%), dry shoot mass (105.54%), number of leaf (30.72%), chlorophyll content (50.41%), and biomass (87.20%) over control under the days of experimental observation. This study was designed for 120 days and was in triplicate and the data was collected at every 30 days.

  19. Pathway engineering of Enterobacter aerogenes to improve acetoin production by reducing by-products formation.

    Science.gov (United States)

    Jang, Ji-Woong; Jung, Hwi-Min; Im, Dae-Kyun; Jung, Moo-Young; Oh, Min-Kyu

    2017-11-01

    Enterobacter aerogenes was metabolically engineered for acetoin production. To remove the pathway enzymes that catalyzed the formation of by-products, the three genes encoding a lactate dehydrogenase (ldhA) and two 2,3-butanediol dehydrogenases (budC, and dhaD), respectively, were deleted from the genome. The acetoin production was higher under highly aerobic conditions. However, an extracellular glucose oxidative pathway in E. aerogenes was activated under the aerobic conditions, resulting in the accumulation of 2-ketogluconate. To decrease the accumulation of this by-product, the gene encoding a glucose dehydrogenase (gcd) was also deleted. The resulting strain did not produce 2-ketogluconate but produced significant amounts of acetoin, with concentration reaching 71.7g/L with 2.87g/L/h productivity in fed-batch fermentation. This result demonstrated the importance of blocking the glucose oxidative pathway under highly aerobic conditions for acetoin production using E. aerogenes. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Synergistic effect of Candida maltosa HY-35 and Enterobacter aerogenes W-23 on hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Wenyu; Wen, Jianping; Chen, Yu.; Sun, Bing; Jia, Xiaoqiang; Liu, Minghui; Caiyin, Qinggele [Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China)

    2007-06-15

    An aciduric high-yielding hydrogen yeast named Candida maltosa HY-35 was screened, which can grow and produce hydrogen at pH 1.3. Further research was carried out batchwise to measure the hydrogen-producing ability of a mixed culture of C. maltosa HY-35 and a facultative anaerobe Enterobacter aerogenes W-23. In this method, with the mixed culture of these two strains at 35 {sup circle} C for 28 h, the hydrogen yield was 1735 ml/l, which was 17.15% and 119.90% higher than those of the monoculture of E. aerogenes W-23 and C. maltosa HY-35, respectively. Meanwhile, the average hydrogen production rate with the mixed culture was 261.1 ml/h/l, which was 7.85% and 146.23% higher than those of the monoculture of E. aerogenes W-23 and C. maltosa HY-35, respectively. The results suggested that mixed culture of these two strains had the synergistic effect on hydrogen production. The optimum fermentation medium and operation conditions for hydrogen production with mixed culture were also investigated. (author)

  1. Rapid Detection of Enterobacter Sakazakii in milk Powder using amino modified chitosan immunomagnetic beads.

    Science.gov (United States)

    Zhu, Yinglian; Wang, Dongfeng

    2016-12-01

    Chitosan immunomagnetic beads (CIBs) were first prepared through converting hydroxyl groups of natural polymer material-chitosan into amino groups using epichlorohydrin and ethylenediamine as modification agent and then coupling with polyclonal antibodies of Enterobacter sakazakii using glutaraldehyde as cross-linking agent. The beads before coupling with antibodies were characterized by magnetic property measurement, FTIR, SEM and XRD technologies. In the assay a natural polysaccharide-chitosan, which has good biological and chemical properties such as non-toxicity, biocompatibility and high chemical reactivity was first used for synthesis of immunomagnetic beads. The detection method first established in this paper that combined the beads with chromogenic medium together to rapid detect E. sakazakii in milk powder could greatly improve the detection specificity and working efficiency. The beads exhibited a maximum capturing capacity of 1×10 6 cfu/g with the detection sensitivity of 4cfu/g. The results demonstrate that the assay is a straightforward, specific and sensitive alternative for rapid detection of E.sakazakii in food matrix. The total analysis time was as little as about 25h, which greatly shorten the detection time. The method can provides new ideas not only to preparation technique of immunomagnetic beads but to imunne detection technique in food safety. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. The purification, crystallization and preliminary diffraction of a glycerophosphodiesterase from Enterobacter aerogenes

    International Nuclear Information System (INIS)

    Jackson, Colin J.; Carr, Paul D.; Kim, Hye-Kyung; Liu, Jian-Wei; Ollis, David L.

    2006-01-01

    The metallo-glycerophosphodiesterase from E. aerogenes (GpdQ) has been cloned, expressed in E. coli and purified. Initial screening of crystallization conditions for this enzyme resulted in the identification of needles from one condition in a sodium malonate grid screen. Removal of the metals from the enzyme and subsequent optimization of these conditions led to crystals. The metallo-glycerophosphodiesterase from Enterobacter aerogenes (GpdQ) has been cloned, expressed in Escherichia coli and purified. Initial screening of crystallization conditions for this enzyme resulted in the identification of needles from one condition in a sodium malonate grid screen. Removal of the metals from the enzyme and subsequent optimization of these conditions led to crystals that diffracted to 2.9 Å and belonged to space group P2 1 3, with unit-cell parameter a = 164.1 Å. Self-rotation function analysis and V M calculations indicated that the asymmetric unit contains two copies of the monomeric enzyme, corresponding to a solvent content of 79%. It is intended to determine the structure of this protein utilizing SAD phasing from transition metals or molecular replacement

  3. Bio-hydrogen production by Enterobacter asburiae SNU-1 isolated from a landfill

    Energy Technology Data Exchange (ETDEWEB)

    Jong-Hwan Shin; Jong Hyun Yoon; Tai Hyun Park [School of Chemical and Biological Engineering, Seoul National University, Seoul 151-744, (Korea, Republic of)

    2006-07-01

    A new fermentative hydrogen-producing bacterium was isolated from a landfill, and it was identified as Enterobacter asburiae strain using a genomic DNA hybridization method. Environmental factors and metabolic flux influencing the hydrogen production were investigated, including pH, initial glucose and formate concentrations. The major hydrogen production pathway of this strain is considered to be a formate pathway by using formate hydrogen lyase (FHL). Optimum pH for the hydrogen production was pH 7.0 in PYG medium, at which hydrogen production/unit volume and overall hydrogen productivity were 2615 ml/l and 174 ml H{sub 2}/l/hr, respectively, at 25 g glucose/l. The maximum hydrogen productivity was estimated to be 417 ml H{sub 2}/l/hr at 15 g glucose/l. This strain produced bio-hydrogen mostly in the stationary phase, in which formate concentration was high. In this paper, hydrogen production was tried in formate medium after cell harvest. (authors)

  4. Electricity generation by Enterobacter cloacae SU-1 in mediator less microbial fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Samrot, Antony V.; Senthilkumar, P.; Pavankumar, K.; Akilandeswari, G.C. [Department of Biotechnology, Sathyabama University, Rajiv Gandhi Salai, Chennai, Tamilnadu (India); Rajalakshmi, N.; Dhathathreyan, K.S. [Center for Fuel Cell Technology ARCI, IITM Research Park, Phase I, 2nd Floor, 6 Kanagam Road, Tharamani, Chennai 600 113, Tamilnadu (India)

    2010-08-15

    We have investigated a Enterobacter cloacae SU-1, bacteria for mediator less microbial fuel cell with different carbon sources and is found to be more effective as the microorganism is able to transfer electrons directly (exo-electrogenic organism) via the cytochromes or the ubiquinone. These carriers of electrons are in form of stable reversible redox couples, not biologically degraded and not toxic to cell. The major advantage of mediator less microbial fuel cells emphasize that additives in the anolyte is not compatible with the purpose of water purification. The anode chamber with the bacteria is maintained under anaerobic conditions so that the bacteria will undergo anaerobic biochemical pathways like Glycolysis, TCA cycle, Electron Transport Chain (ETC) where electrons and protons are released. Here protons are released in TCA cycle and whereas electrons are released from ETC. The mediator less microbial fuel cell delivered an open circuit potential (OCP) of 0.93 V and power of 3 mW/sq cm. During power generation from the microbes, there was a drop in coulombic efficiency in terms of fluctuations during drawing power, as the carbon source is being utilized for the cell growth. (author)

  5. Bio-hydrogen production by Enterobacter asburiae SNU-1 isolated from a landfill

    International Nuclear Information System (INIS)

    Jong-Hwan Shin; Jong Hyun Yoon; Tai Hyun Park

    2006-01-01

    A new fermentative hydrogen-producing bacterium was isolated from a landfill, and it was identified as Enterobacter asburiae strain using a genomic DNA hybridization method. Environmental factors and metabolic flux influencing the hydrogen production were investigated, including pH, initial glucose and formate concentrations. The major hydrogen production pathway of this strain is considered to be a formate pathway by using formate hydrogen lyase (FHL). Optimum pH for the hydrogen production was pH 7.0 in PYG medium, at which hydrogen production/unit volume and overall hydrogen productivity were 2615 ml/l and 174 ml H 2 /l/hr, respectively, at 25 g glucose/l. The maximum hydrogen productivity was estimated to be 417 ml H 2 /l/hr at 15 g glucose/l. This strain produced bio-hydrogen mostly in the stationary phase, in which formate concentration was high. In this paper, hydrogen production was tried in formate medium after cell harvest. (authors)

  6. Determination for Enterobacter cloacae based on a europium ternary complex labeled DNA probe

    Science.gov (United States)

    He, Hui; Niu, Cheng-Gang; Zeng, Guang-Ming; Ruan, Min; Qin, Pin-Zhu; Liu, Jing

    2011-11-01

    The fast detection and accurate diagnosis of the prevalent pathogenic bacteria is very important for the treatment of disease. Nowadays, fluorescence techniques are important tools for diagnosis. A two-probe tandem DNA hybridization assay was designed for the detection of Enterobacter cloacae based on time-resolved fluorescence. In this work, the authors synthesized a novel europium ternary complex Eu(TTA) 3(5-NH 2-phen) with intense luminescence, high fluorescence quantum yield and long lifetime before. We developed a method based on this europium complex for the specific detection of original extracted DNA from E. cloacae. In the hybridization assay format, the reporter probe was labeled with Eu(TTA) 3(5-NH 2-phen) on the 5'-terminus, and the capture probe capture probe was covalent immobilized on the surface of the glutaraldehyde treated glass slides. The original extracted DNA of samples was directly used without any DNA purification and amplification. The detection was conducted by monitoring the fluorescence intensity from the glass surface after DNA hybridization. The detection limit of the DNA was 5 × 10 -10 mol L -1. The results of the present work proved that this new approach was easy to operate with high sensitivity and specificity. It could be conducted as a powerful tool for the detection of pathogen microorganisms in the environment.

  7. The purification, crystallization and preliminary diffraction of a glycerophosphodiesterase from Enterobacter aerogenes

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, Colin J.; Carr, Paul D.; Kim, Hye-Kyung; Liu, Jian-Wei; Ollis, David L., E-mail: ollis@rsc.anu.edu.au [The Research School of Chemistry, Australian National University, ACT 0200 (Australia)

    2006-07-01

    The metallo-glycerophosphodiesterase from E. aerogenes (GpdQ) has been cloned, expressed in E. coli and purified. Initial screening of crystallization conditions for this enzyme resulted in the identification of needles from one condition in a sodium malonate grid screen. Removal of the metals from the enzyme and subsequent optimization of these conditions led to crystals. The metallo-glycerophosphodiesterase from Enterobacter aerogenes (GpdQ) has been cloned, expressed in Escherichia coli and purified. Initial screening of crystallization conditions for this enzyme resulted in the identification of needles from one condition in a sodium malonate grid screen. Removal of the metals from the enzyme and subsequent optimization of these conditions led to crystals that diffracted to 2.9 Å and belonged to space group P2{sub 1}3, with unit-cell parameter a = 164.1 Å. Self-rotation function analysis and V{sub M} calculations indicated that the asymmetric unit contains two copies of the monomeric enzyme, corresponding to a solvent content of 79%. It is intended to determine the structure of this protein utilizing SAD phasing from transition metals or molecular replacement.

  8. Inactivation of Enterobacter sakazakii of dehydrated infant formula by gamma-irradiation

    International Nuclear Information System (INIS)

    Lee, Ju-Woon; Oh, Sang-Hee; Byun, Eui-Baek; Kim, Jae-Hun; Kim, Jang-Ho; Woon, Jae-Ho; Byun, Myung-Woo

    2007-01-01

    Enterobacter sakazakii has been implicated as a causal organism in a severe form of neonatal meningitis, with reported mortality rates of 20%. The population at greatest risk is immunocompromised infants of any age. Dried infant formula has been identified as a potential source of the organism in both outbreaks and sporadic cases. The objective of this study was to investigate theirradiation effect of the inactivation on E. sakazakii (ATCC 29544) of a dehydrated infant formula. The D 10 -values were 0.22-0.27 and 0.76 kGy for broth and dehydrated infant formula, respectively. The irradiation at 5.0 kGy was able to completely eliminate the E. sakazakii inoculated at 8.0 to 9.0 log CFU g -1 onto a dehydrated infant formula. There was no regrowth for all samples during the time they were stored at 10 deg. C for 6 h after rehydration. The present results indicated that a gamma-irradiation could potentially be used to inactivate E. sakazakii in a dehydrated powdered infant formula

  9. Inactivation of Enterobacter sakazakii of dehydrated infant formula by gamma-irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ju-Woon; Oh, Sang-Hee [Radiation Application Research Division, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580 185 (Korea, Republic of); Byun, Eui-Baek [Radiation Application Research Division, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580 185 (Korea, Republic of); Graduate School of Biotechnology, Korea University, Yeongi 339-700 (Korea, Republic of); Kim, Jae-Hun; Kim, Jang-Ho [Radiation Application Research Division, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580 185 (Korea, Republic of); Woon, Jae-Ho [Livestock Products standard Division, National Veterinary Research and Quarantine Service, Anyang 430-824 (Korea, Republic of); Byun, Myung-Woo [Radiation Application Research Division, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580 185 (Korea, Republic of)], E-mail: mwbyun@kaeri.re.kr

    2007-11-15

    Enterobacter sakazakii has been implicated as a causal organism in a severe form of neonatal meningitis, with reported mortality rates of 20%. The population at greatest risk is immunocompromised infants of any age. Dried infant formula has been identified as a potential source of the organism in both outbreaks and sporadic cases. The objective of this study was to investigate theirradiation effect of the inactivation on E. sakazakii (ATCC 29544) of a dehydrated infant formula. The D{sub 10}-values were 0.22-0.27 and 0.76 kGy for broth and dehydrated infant formula, respectively. The irradiation at 5.0 kGy was able to completely eliminate the E. sakazakii inoculated at 8.0 to 9.0 log CFU g{sup -1} onto a dehydrated infant formula. There was no regrowth for all samples during the time they were stored at 10 deg. C for 6 h after rehydration. The present results indicated that a gamma-irradiation could potentially be used to inactivate E. sakazakii in a dehydrated powdered infant formula.

  10. Regulation of hydrogen production by Enterobacter aerogenes by external NADH and NAD{sup +}

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Chong; Ma, Kun; Xing, Xin-Hui [Department of Chemical Engineering, Tsinghua University, Beijing 100084 (China)

    2009-02-15

    Experiments involving the addition of external nicotinamide adenine dinucleotide, reduced form (NADH) or nicotinamide adenine dinucleotide (NAD{sup +}) have been designed to examine how the hydrogen in Enterobacter aerogenes is liberated by NADH or NAD{sup +}. The addition of external NADH or NAD{sup +} was found to regulate hydrogen production by E. aerogenes in resting cells, batch cultures, and chemostat cultures. Particularly in chemostat cultivation, with the external addition of NADH, hydrogen production via the NADH pathway was decreased, while that via the formate pathway was increased; in the end, the overall hydrogen p was decreased. The addition of NAD{sup +}, on the other hand, gave the opposite results. The membrane-bound hydrogenase was found to play a central role in regulating hydrogen production. The occurrence of NADH oxidation (NAD{sup +} reduction) on the cell membrane resulted in an electron flow across the membrane; this changed the oxidation state and metabolic pattern of the cells, which eventually affected the hydrogen evolution. (author)

  11. Hydrogen production from the monomeric sugars hydrolyzed from hemicellulose by Enterobacter aerogenes

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Yunli; Wang, Jianji; Liu, Zhen; Ren, Yunlai; Li, Guozhi [School of Chemical Engineering and Pharmaceutics, Henan University of Science and Technology, Luoyang 471039, Henan (China)

    2009-12-15

    Relatively large percentages of xylose with glucose, arabinose, mannose, galactose and rhamnose constitute the hydrolysis products of hemicellulose. In this paper, hydrogen production performance of facultative anaerobe (Enterobacter aerogenes) has been investigated from these different monomeric sugars except glucose. It was shown that the stereoisomers of mannose and galactose were more effective for hydrogen production than those of xylose and arabinose. The substrate of 5 g/l xylose resulted in a relative high level of hydrogen yield (73.8 mmol/l), hydrogen production efficiency (2.2 mol/mol) and a maximum hydrogen production rate (249 ml/l/h). The hydrogen yield, hydrogen production efficiency and the maximum hydrogen production rate reached 104 mmol/l, 2.35 mol/mol and 290 ml/l/h, respectively, on a substrate of 10 g/l galactose. The hydrogen yields and the maximum hydrogen production rates increased with an increase of mannose concentrations and reached 119 mmol/l and 518 ml/l/h on the culture of 25 g/l mannose. However, rhamnose was a relative poor carbon resource for E. aerogenes to produce hydrogen, from which the hydrogen yield and hydrogen production efficiency were about one half of that from the mannose substrate. E. aerogenes was found to be a promising strain for hydrogen production from hydrolysis products of hemicellulose. (author)

  12. Inactivation of Enterobacter sakazakii of dehydrated infant formula by gamma-irradiation

    Science.gov (United States)

    Lee, Ju-Woon; Oh, Sang-Hee; Byun, Eui-Baek; Kim, Jae-Hun; Kim, Jang-Ho; Woon, Jae-Ho; Byun, Myung-Woo

    2007-11-01

    Enterobacter sakazakii has been implicated as a causal organism in a severe form of neonatal meningitis, with reported mortality rates of 20%. The population at greatest risk is immunocompromised infants of any age. Dried infant formula has been identified as a potential source of the organism in both outbreaks and sporadic cases. The objective of this study was to investigate theirradiation effect of the inactivation on E. sakazakii (ATCC 29544) of a dehydrated infant formula. The D10-values were 0.22-0.27 and 0.76 kGy for broth and dehydrated infant formula, respectively. The irradiation at 5.0 kGy was able to completely eliminate the E. sakazakii inoculated at 8.0 to 9.0 log CFU g -1 onto a dehydrated infant formula. There was no regrowth for all samples during the time they were stored at 10 °C for 6 h after rehydration. The present results indicated that a gamma-irradiation could potentially be used to inactivate E. sakazakii in a dehydrated powdered infant formula.

  13. Bio-hydrogen production from glycerol by a strain of Enterobacter aerogenes

    Energy Technology Data Exchange (ETDEWEB)

    Marques, P.A.S.S; Bartolomeu, M.L.; Tome, M.M.; Rosa, M.F. [INETI, Unit of Biomass/Renewable Energy Department, Estrada do Paco do Lumiar, 22, 1649-038 Lisboa (Portugal)

    2008-07-01

    The goal of this work was to evaluate the H2 production from glycerol-containing byproducts obtained from biodiesel industrial production, using Enterobacter aerogenes ATCC 13048 Sputum. H2 production using as substrate pure glycerol and glycerol-containing biodiesel byproducts was compared. The effect of parameters such as initial substrate concentration and sodium chloride addition on the bio-hydrogen production efficiency was also investigated. The results showed that using 10 g/L of pure glycerol or biodiesel residues, containing the same concentration of glycerol as substrate, lead to similar bio-hydrogen productions (3.46 LH2/L and 3.28 LH2/L fermentation medium, respectively). This indicates that the performance of the E. aerogenes strain used was not influenced by the presence of other components than glycerol in biodiesel residues, at least for the tested waste concentration range. When sodium chloride was added to the fermentation medium with pure 10 g/L glycerol, H2 production was not affected (3.34 LH2/L fermentation medium), showing that metabolism of the E. aerogenes strain was not inhibited by this biodiesel waste component up to 4 g/L chloride concentration. Biodiesel residues used without sterilization provided a higher H2 production (1.03 L) than the ones submitted to previous sterilization in autoclave (0.89 L).

  14. Colistin resistance associated with outer membrane protein change in Klebsiella pneumoniae and Enterobacter asburiae.

    Science.gov (United States)

    Kádár, Béla; Kocsis, Béla; Tóth, Ákos; Kristóf, Katalin; Felső, Péter; Kocsis, Béla; Böddi, Katalin; Szabó, Dóra

    2017-06-01

    In this study, outer membrane proteins (OMPs) of colistin-resistant Klebsiella pneumoniae and Enterobacter asburiae were analyzed. One colistin-susceptible and three colistin-resistant K. pneumoniae sequence type 258 strains as well as one colistin-susceptible E. asburiae and its colistin-heteroresistant counterpart strain were involved in the study. OMP analysis of each strain was performed by microchip method. Matrix-assisted laser desorption ionization time of flight/mass spectrometry (MALDI-TOF/MS) investigation was carried out after separation of OMPs by two-dimensional gel electrophoresis and in-gel digestion. The MALDI-TOF/MS analysis of OMPs in the colistin-susceptible K. pneumoniae found 16 kDa proteins belonging to the LysM domain/BON superfamily, as well as DNA starvation proteins, whereas OmpX and OmpW were detected in the colistin-resistant counterpart strains. OmpC and OmpW were detected in the colistin-susceptible E. asburiae, whereas OmpA and OmpX were identified in the colistin-resistant counterpart. This study demonstrated that OMP differences were between colistin-susceptible and -resistant counterpart strains. The altered Gram-negative cell wall may contribute to acquired colistin resistance in Enterobacteriaceae.

  15. Hydrogen production of Enterobacter aerogenes altered by extracellular and intracellular redox states

    Energy Technology Data Exchange (ETDEWEB)

    Nakashimada, Y.; Rachman, M.A.; Kakizono, T.; Nishio, N. [Hiroshima University, Higashi-Hiroshima (Japan). Graduate School of Advanced Sciences of Matter, Department of Molecular Biotechnology

    2002-12-01

    Enterobacter aerogenes HU-101, tested for its hydrogen production in batch cultures on various substrates, produced the highest amount of hydrogen when the substrate was glycerol. The yield of hydrogen is a function of the degree to which the substrates are reduced. To examine the effect of intracellular redox state on hydrogen yield, glucose-limiting chemostat cultures were carried out at various pH using strain HU-101 and its mutant AY-2. For both strains, the molar yield and the production rate of hydrogen and the hydrogenase activity in the cell-free extract were optimal at the culture pH of 6.3. The highest NADH/NAD ratio in both strains was also observed at pH 6.3, at which the ratio in AY-2 was more than two-fold that of HU-101. Furthermore, NAD(P)H-dependent hydrogen formation was observed in the cell-free extract of AY-2, and hydrogenase activity was found not in the cytoplasmic but in the cell membrane fraction, suggesting that a high intracellular redox state, that is a high NADH/NAD ratio, would accelerate hydrogen production by driving membrane-bound NAD(P)H-dependent hydrogenase. (author)

  16. Extreme furfural tolerance of a soil bacterium Enterobacter cloacae GGT036.

    Science.gov (United States)

    Choi, Sun Young; Gong, Gyeongtaek; Park, Hong-Sil; Um, Youngsoon; Sim, Sang Jun; Woo, Han Min

    2015-01-10

    Detoxification process of cellular inhibitors including furfural is essential for production of bio-based chemicals from lignocellulosic biomass. Here we isolated an extreme furfural-tolerant bacterium Enterobacter cloacae GGT036 from soil sample collected in Mt. Gwanak, Republic of Korea. Among isolated bacteria, only E. cloacae GGT036 showed cell growth with 35 mM furfural under aerobic culture. Compared to the maximal half inhibitory concentration (IC50) of well-known industrial strains Escherichia coli (24.9 mM furfural) and Corynebacterium glutamicum (10 mM furfural) based on the cell density, IC50 of E. cloacae GGT036 (47.7 mM) was significantly higher after 24 h, compared to E. coli and C. glutamicum. Since bacterial cell growth was exponentially inhibited depending on linearly increased furfural concentrations in the medium, we concluded that E. cloacae GGT036 is an extreme furfural-tolerant bacterium. Recently, the complete genome sequence of E. cloacae GGT036 was announced and this could provide an insight for engineering of E. cloacae GGT036 itself or other industrially relevant bacteria. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Enterobacter aerogenes metabolites enhance Microcystis aeruginosa biomass recovery for sustainable bioflocculant and biohydrogen production.

    Science.gov (United States)

    Xu, Liang; Zhou, Mo; Ju, Hanyu; Zhang, Zhenxing; Zhang, Jiquan; Sun, Caiyun

    2018-04-07

    We report a recycling bioresource involving harvesting of Microcystis aeruginosa using the bioflocculant (MBF-32) produced by Enterobacter aerogenes followed by the recovery of the harvested M. aeruginosa as the main substrate for the sustainable production of MBF-32 and biohydrogen. The experimental results indicate that the efficiency of bioflocculation exceeded 90% under optimal conditions. The harvested M. aeruginosa was further recycled as the main substrate for the supply of necessary elements. The highest yield (3.6±0.1g/L) of MBF-32 could be obtained from 20g/L of wet biomass of M. aeruginosa with an additional 20g/L of glucose as the extra carbon source. The highest yield of biohydrogen was 35mL of H 2 /g (dw) algal biomass, obtained from 20g/L of wet biomass of M. aeruginosa with an additional 10g/L of glycerol. Transcriptome analyses indicated that MBF-32 was mainly composed of polysaccharide and tyrosine/tryptophan proteins. Furthermore, NADH synthase and polysaccharide export-related genes were found to be up-regulated. Copyright © 2018 Elsevier B.V. All rights reserved.

  18. Inactivation of Enterobacter aerogenes in reconstituted skim milk by high- and low-frequency ultrasound.

    Science.gov (United States)

    Gao, Shengpu; Hemar, Yacine; Lewis, Gillian D; Ashokkumar, Muthupandian

    2014-11-01

    The inactivation of Enterobacter aerogenes in skim milk using low-frequency (20kHz) and high-frequency (850kHz) ultrasonication was investigated. It was found that low-frequency acoustic cavitation resulted in lethal damage to E. aerogenes. The bacteria were more sensitive to ultrasound in water than in reconstituted skim milk having different protein concentrations. However, high-frequency ultrasound was not able to inactivate E. aerogenes in milk even when powers as high as 50W for 60min were used. This study also showed that high-frequency ultrasonication had no influence on the viscosity and particle size of skim milk, whereas low-frequency ultrasonication resulted in the decrease in viscosity and particle size of milk. The decrease in particle size is believed to be due to the breakup of the fat globules, and possibly to the cleavage of the κ-casein present at the surface of the casein micelles. Whey proteins were also found to be slightly affected by low-frequency ultrasound, with the amounts of α-lactalbumin and β-lactoglobulin slightly decreasing. Copyright © 2013. Published by Elsevier B.V.

  19. Isolation of Enterobacter sakazakii from ass' milk in Sicily: case report, safety and legal issues.

    Science.gov (United States)

    Conte, F; Passantino, A

    2008-07-01

    Enterobacter sakazakii (Es) infections are likely to involve newborns and infants, causing meningitis and necrotizing enterocolitis and sepsis. Contamination of infant formulae milk during factory production or bottle preparation is implicated. Es has been isolated from environmental sources and from food other than infant formula and milk powder, but why it is associated only with the consumption of infant formulae, is unclear. According to Regulation (EC) No. 2073/2005 on the microbiological criteria for foodstuffs, Es is considered a microorganisms of greatest concern in infant formulae and follow-on formulae. Es is included between "safety criteria". The isolation of two strains of Es from 50 samples of ass' milk in Sicily is described. The antibiotic resistance profile of the isolates revealed a multiple resistance profile, including fluoroquinolones, commonly used to treat the infections. The authors underline the importance of survey because in Italy ass' milk is considered one of the solutions for infants suffering from hypersensitivity to milk protein of some animal species. There is scarce information about the ecology and the uncertainty concerning the source of infection in the children and adults; the authors are concerned that ass' milk could become a high-risk food.

  20. Particular Distribution of Enterobacter cloacae Strains Isolated from Urinary Tract Infection within Clonal Complexes.

    Science.gov (United States)

    Akbari, Majid; Bakhshi, Bita; Najar Peerayeh, Shahin

    2016-01-01

    Based on biochemical properties, Enterobacter cloacae represents a large complex of at least 13 variant species, subspecies, and genotypes that progressively identified as the most species causing hospital-acquired infections. The aim of this study was to determine the relevance between phylogenetically related strains within the E. cloacae complex and the frequency of urinary tract infection caused by them. A 268-bp fragment was obtained from hsp60 gene for 50 clinical E. cloacae isolates from urine cultures of inpatients that admitted to six hospitals in Tehran, Iran during December 2012 to November 2013. The 107 nucleotide sequences were analyzed and the evolutionary distances of sequences were computed and neighbor-joining tree was calculated. It showed that all of the genetic clusters have not an equal involvement in pathogenesis of urinary tract infections. Three superior clusters were found, together representing more than two third (80%) of the isolates (cluster VI with 25 members; clusters III and VIII with 9 and 6 members, respectively) and some genetic clusters were absent (IV, X, XII, and xiii), some of which are supposed to be associated with plants and no human infection has been reported. This study, for the first time, reports the unequal contribution of E. cloacae complex subspecies and clusters in urinary tract infections in Iran and together with studies from other countries suggest that the subspecies of E.hormaechei subsp. Oharae is the most prevalent E. cloacae complex subspecies regardless of country under study.

  1. Establishment of a Molecular Serotyping Scheme and a Multiplexed Luminex-Based Array for Enterobacter aerogenes.

    Science.gov (United States)

    Guo, Xi; Wang, Min; Wang, Lu; Wang, Yao; Chen, Tingting; Wu, Pan; Chen, Min; Liu, Bin; Feng, Lu

    2018-01-01

    Serotyping based on surface polysaccharide antigens is important for the clinical detection and epidemiological surveillance of pathogens. Polysaccharide gene clusters (PSgcs) are typically responsible for the diversity of bacterial surface polysaccharides. Through whole-genome sequencing and analysis, eight putative PSgc types were identified in 23 Enterobacter aerogenes strains from several geographic areas, allowing us to present the first molecular serotyping system for E. aerogenes . A conventional antigenic scheme was also established and correlated well with the molecular serotyping system that was based on PSgc genetic variation, indicating that PSgc-based molecular typing and immunological serology provide equally valid results. Further, a multiplex Luminex-based array was developed, and a double-blind test was conducted with 97 clinical specimens from Shanghai, China, to validate our array. The results of these analyses indicated that strains containing PSgc4 and PSgc7 comprised the predominant groups. We then examined 86 publicly available E. aerogenes strain genomes and identified an additional seven novel PSgc types, with PSgc10 being the most abundant type. In total, our study identified 15 PSgc types in E. aerogenes , providing the basis for a molecular serotyping scheme. From these results, differing epidemic patterns were identified between strains that were predominant in different regions. Our study highlights the feasibility and reliability of a serotyping system based on PSgc diversity, and for the first time, presents a molecular serotyping system, as well as an antigenic scheme for E. aerogenes , providing the basis for molecular diagnostics and epidemiological surveillance of this important emerging pathogen.

  2. SP-100 Program overview

    International Nuclear Information System (INIS)

    Truscello, V.C.

    1984-01-01

    The SP-100 Program is expected to go through three phases: technology assessment and advancement, ground testing, and flight qualification. Currently the program is in the two- to three-year technology assessment and advancement stage. Goals are to identify the space nuclear power system concept that best meets anticipated requirements of future space missions, assess the technical feasibility of that concept, and establish a cost and schedule for developing the concept. The SP-100 Project Office has begun the implementation activities needed to meet these goals. With regard to refractory alloys, a better data base will be required before we move ahead in the program from technology assessment to ground demonstration

  3. Dominance of IMP-4-Producing Enterobacter cloacae among Carbapenemase-Producing Enterobacteriaceae in Australia

    Science.gov (United States)

    Townell, Nicola; Nimmo, Graeme R.; George, Narelle M.; Robson, Jennifer; Vohra, Renu; Davis, Louise; Heney, Claire; Paterson, David L.

    2015-01-01

    The prevalence of carbapenemase-producing Enterobacteriaceae (CPE) has been increasing worldwide. blaIMP has been reported to be the predominant carbapenemase-encoding gene within Enterobacteriaceae in Australia. However, there are limited data currently available on CPE from Queensland, Australia. A total of 58 CPE isolates were isolated between July 2009 and March 2014 from Queensland hospitals. The clonality of isolates was determined by Diversilab repetitive sequence-based PCR. The isolates were investigated for the resistance mechanisms carbapenemase, extended-spectrum β-lactamase, and AmpC β-lactamase and for aminoglycoside resistance and plasmid-mediated quinolone resistance genes by PCR. The plasmid types associated with carbapenemase-encoding genes were characterized. The majority of the CPE were Enterobacter cloacae (n = 29). The majority of Queensland CPE isolates were IMP producers and comprised 11 species (n = 48). Nine NDM-producing Enterobacteriaceae were identified. One NDM-producing Klebsiella pneumoniae isolate coproduced OXA-48. One K. pneumoniae isolate was an OXA-181 producer. The incidence of IMP producers increased significantly in 2013. blaIMP-4 was found in all IMP-producing isolates. blaTEM, qnrB, and aacA4 were common among IMP-4 producers. The HI2 (67%) and L/M (21%) replicons were associated with blaIMP-4. All HI2 plasmids were of sequence type 1 (ST1). All but one of the NDM producers possessed blaCTX-M-15. The 16S rRNA methylase genes found among NDM producers were armA, rmtB, rmtC, and rmtF. The substantial increase in the prevalence of CPE in Queensland has been associated mainly with the emergence E. cloacae strains possessing HI2 plasmids carrying blaIMP-4 over the past 2 years. The importation of NDM producers and/or OXA-48-like producers in patients also contributed to the increased emergence of CPE. PMID:25918153

  4. Characterization of endo-β-mannanase from Enterobacter ludwigii MY271 and application in pulp industry.

    Science.gov (United States)

    Yang, Miao; Cai, Jun; Wang, Changgao; Du, Xin; Lin, Jianguo

    2017-01-01

    β-Mannanases are the second most important enzymes for the hydrolysis of hemicelluloses. An endo-β-mannanase from Enterobacter ludwigii MY271 was purified at 11.7 ± 0.2-fold to homogeneity with a final recovery of 15.2 ± 0.2 %. Using purified β-mannanase protein and SDS-PAGE, the molecular mass was found to be 43.16 kDa. The optimal pH and temperature of the enzyme was found to be 7.0 and 55 °C, respectively. The β-mannanase activity was stable over a broad pH range of pH 2.0-10.0. In addition, the purified enzyme was highly activated by several metal ions and chemical reagents, such as Mg 2+ , L-cysteine, glutathione (GSH) and β-mercaptoethanol. Whereas the enzyme was strongly inhibited by Hg 2+ , Cu 2+ , N-bromosuccinimide (NBS), 1-ethyl-3-(3-dimethyl-amino-propyl)-carbodiimide (EDC), phenylmethanesulfonyl fluoride (PMSF), and sodium dodecyl sulfate (SDS). The β-mannanase was highly active towards glucomannan, and showed endo-activity by producing a mixture of oligosaccharides. Moreover, the enzyme displayed a classical endo-type mode on mannooligosaccharides. The β-mannanase coupled with xylanase significantly improved the brightness of kraft pulp, whereas it has no remarkable effect on the tensile strength of the pulp. Our functional studies of the purified β-mannanase indicate that the enzyme is beneficial to industrial applications, in particular, biotechnological processes, such as food, feed and pulp industry.

  5. Sucrose dependent mineral phosphate solubilization in Enterobacter asburiae PSI3 by heterologous overexpression of periplasmic invertases.

    Science.gov (United States)

    Kumar, Chanchal; Wagh, Jitendra; Archana, G; Naresh Kumar, G

    2016-12-01

    Enterobacter asburiae PSI3 solubilizes mineral phosphates in the presence of glucose by the secretion of gluconic acid generated by the action of a periplasmic pyrroloquinoline quinone dependent glucose dehydrogenase. In order to achieve mineral phosphate solubilization phenotype in the presence of sucrose, plasmids pCNK4 and pCNK5 containing genes encoding the invertase enzyme of Zymomonas mobilis (invB) and of Saccharomyces cerevisiae (suc2) under constitutive promoters were constructed with malE signal sequence (in case of invB alone as the suc2 is secreted natively). When introduced into E. asburiae PSI3, E. a. (pCNK4) and E. a. (pCNK5) transformants secreted 21.65 ± 0.94 and 22 ± 1.3 mM gluconic acid, respectively, in the presence of 75 mM sucrose and they also solubilized 180 ± 4.3 and 438 ± 7.3 µM P from the rock phosphate. In the presence of a mixture of 50 mM sucrose and 25 mM glucose, E. a. (pCNK5) secreted 34 ± 2.3 mM gluconic acid and released 479 ± 8.1 µM P. Moreover, in the presence of a mixture of eight sugars (10 mM each) in the medium, E. a. (pCNK5) released 414 ± 5.3 µM P in the buffered medium. Thus, this study demonstrates incorporation of periplasmic invertase imparted P solubilization ability to E. asburiae PSI3 in the presence of sucrose and mixture of sugars.

  6. Longer Contact Times Increase Cross-Contamination of Enterobacter aerogenes from Surfaces to Food.

    Science.gov (United States)

    Miranda, Robyn C; Schaffner, Donald W

    2016-11-01

    Bacterial cross-contamination from surfaces to food can contribute to foodborne disease. The cross-contamination rate of Enterobacter aerogenes on household surfaces was evaluated by using scenarios that differed by surface type, food type, contact time (food types were watermelon, bread, bread with butter, and gummy candy. Surfaces (25 cm 2 ) were spot inoculated with 1 ml of inoculum and allowed to dry for 5 h, yielding an approximate concentration of 10 7 CFU/surface. Foods (with a 16-cm 2 contact area) were dropped onto the surfaces from a height of 12.5 cm and left to rest as appropriate. Posttransfer, surfaces and foods were placed in sterile filter bags and homogenized or massaged, diluted, and plated on tryptic soy agar. The transfer rate was quantified as the log percent transfer from the surface to the food. Contact time, food, and surface type all had highly significant effects (P food, while the least bacteria transferred to gummy candy (∼0.1 to 62%). Transfer of bacteria to bread (∼0.02 to 94%) was similar to transfer of bacteria to bread with butter (∼0.02 to 82%), and these transfer rates under a given set of conditions were more variable than with watermelon and gummy candy. The popular notion of the "five-second rule" is that food dropped on the floor and left there for foods (watermelon, bread, bread with butter, and gummy candy), four different contact times (food and the surface, are of equal or greater importance. Some transfer takes place "instantaneously," at times of <1 s, disproving the five-second rule. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  7. Effect of nanocomposite packaging containing ZnO on growth of Bacillus subtilis and Enterobacter aerogenes

    Energy Technology Data Exchange (ETDEWEB)

    Esmailzadeh, Hakimeh [National Nutrition and Food Technology Research Institute, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of); Sangpour, Parvaneh, E-mail: Sangpour@merc.ac.ir [Nanotechnology and Advanced Materials Department, Materials and Energy Research Center, Karaj (Iran, Islamic Republic of); Shahraz, Farzaneh [National Nutrition and Food Technology Research Institute, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of); Hejazi, Jalal [Department of Biochemistry and Nutrition, Faculty of Medicine, Zanjan University of Medical Sciences, Zanjan (Iran, Islamic Republic of); Khaksar, Ramin [National Nutrition and Food Technology Research Institute, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of)

    2016-01-01

    Recent advances in nanotechnology have opened new windows in active food packaging. Nano-sized ZnO is an inexpensive material with potential antimicrobial properties. The aim of the present study is to evaluate the antibacterial effect of low density Polyethylene (LDPE) containing ZnO nanoparticles on Bacillus subtilis and Enterobacter aerogenes. ZnO nanoparticles have been synthesized by facil molten salt method and have been characterized by X-ray diffraction (XRD), and scanning electron microscopy (SEM). Nanocomposite films containing 2 and 4 wt.% ZnO nanoparticles were prepared by melt mixing in a twin-screw extruder. The growth of both microorganisms has decreased in the presence of ZnO containing nanocomposites compared with controls. Nanocomposites with 4 wt.% ZnO nanoparticles had stronger antibacterial effect against both bacteria in comparison with the 2 wt.% ZnO containing nanocomposites. B. subtilis as Gram-positive bacteria were more sensitive to ZnO containing nanocomposite films compared with E. aerogenes as Gram-negative bacteria. There were no significant differences between the migration of Zn ions from 2 and 4 wt.% ZnO containing nanocomposites and the released Zn ions were not significantly increased in both groups after 14 days compared with the first. Regarding the considerable antibacterial effects of ZnO nanoparticles, their application in active food packaging can be a suitable solution for extending the shelf life of food. - Highlights: • ZnO containing nanocomposites decreased growth of both B. subtilis and E. aerogenes. • B. subtilis was more sensitive to ZnO containing nanocomposites. • The migration of Zn ions from nanocomposites was negligible.

  8. Antimicrobial susceptibility and molecular epidemiology of clinical Enterobacter cloacae bloodstream isolates in Shanghai, China.

    Directory of Open Access Journals (Sweden)

    Su Wang

    Full Text Available Enterobacter cloacae is a major nosocomial pathogen causing bloodstream infections. We retrospectively conducted a study to assess antimicrobial susceptibility and phylogenetic relationships of E. cloacae bloodstream isolates in two tertiary university-affiliated hospitals in Shanghai, in order to facilitate managements of E. cloacae bloodstream infections and highlight some unknowns for future prevention.Fifty-three non-duplicate E. cloacae bloodstream isolates were consecutively collected from 2013 to 2016. Antimicrobial susceptibility was determined by disk diffusion. PCR was performed to detect extended-spectrum β-lactamase (ESBL, carbapenemase and colistin resistance (MCR-1 gene. Plasmid-mediated AmpC β-lactamase (pAmpC genes were detected using a multiplex PCR assay targeting MIR/ACT gene (closely related to chromosomal EBC family gene and other plasmid-mediated genes, including DHA, MOX, CMY, ACC, and FOX. eBURST was applied to analyze multi-locus sequence typing (MLST.The rates of resistance to all tested antibiotics were 0.05. SHV (6/8, 75.0% and MIR/ACT (15/18, 83.3% predominated in ESBL and pAmpC producers respectively. Moreover, 2 isolates co-carried TEM-1, SHV-12, IMP-26 and DHA-1. MLST analysis distinguished the 53 isolates into 51 STs and only ST414 and ST520 were assigned two isolates of each (2/53.The antimicrobial resistance rates were low among 53 E. cloacae bloodstream isolates in the two hospitals. Multiclonality disclosed no evidence on spread of these isolates in Shanghai. The simultaneous presence of ESBL, carbapenemase and pAmpC detected in 2 isolates was firstly reported in Shanghai, which necessitated active ongoing surveillances and consistent prevention and control of E. cloacae.

  9. Attachment of and biofilm formation by Enterobacter sakazakii on stainless steel and enteral feeding tubes.

    Science.gov (United States)

    Kim, Hoikyung; Ryu, Jee-Hoon; Beuchat, Larry R

    2006-09-01

    Enterobacter sakazakii has been reported to form biofilms, but environmental conditions affecting attachment to and biofilm formation on abiotic surfaces have not been described. We did a study to determine the effects of temperature and nutrient availability on attachment and biofilm formation by E. sakazakii on stainless steel and enteral feeding tubes. Five strains grown to stationary phase in tryptic soy broth (TSB), infant formula broth (IFB), or lettuce juice broth (LJB) at 12 and 25 degrees C were examined for the extent to which they attach to these materials. Higher populations attached at 25 degrees C than at 12 degrees C. Stainless steel coupons and enteral feeding tubes were immersed for 24 h at 4 degrees C in phosphate-buffered saline suspensions (7 log CFU/ml) to facilitate the attachment of 5.33 to 5.51 and 5.03 to 5.12 log CFU/cm(2), respectively, before they were immersed in TSB, IFB, or LJB, followed by incubation at 12 or 25 degrees C for up to 10 days. Biofilms were not produced at 12 degrees C. The number of cells of test strains increased by 1.42 to 1.67 log CFU/cm(2) and 1.16 to 1.31 log CFU/cm(2) in biofilms formed on stainless steel and feeding tubes, respectively, immersed in IFB at 25 degrees C; biofilms were not formed on TSB and LJB at 25 degrees C, indicating that nutrient availability plays a major role in processes leading to biofilm formation on the surfaces of these inert materials. These observations emphasize the importance of temperature control in reconstituted infant formula preparation and storage areas in preventing attachment and biofilm formation by E. sakazakii.

  10. Physiological and biochemical role of the butanediol pathway in Aerobacter (Enterobacter) aerogenes.

    Science.gov (United States)

    Johansen, L; Bryn, K; Stormer, F C

    1975-01-01

    Aerobacter (Enterobacter) aerogenes wild type and three mutants deficient in the formation of acetoin and 2,3-butanediol were grown in a glucose minimal medium. Culture densities, pH, and diacetyl, acetoin, and 2,3-butanediol levels were recorded. The pH in wild-type cultures dropped from 7.0 to 5.8, remained constant while acetoin and 2,3-butanediol were formed, and increased to pH 6.5 after exhaustion of the carbon source. More 2,3-butanediol than acetoin was formed initially, but after glucose exhaustion reoxidation to acetoin occurred. The three mutants differed from the wild type in yielding acid cultures (pH below 4.5). The wild type and one of the mutants were grown exponentially under aerobic and anaerobic conditions with the pH fixed at 7.0, 5.8, and 5.0, respectively. Growth rates decreased with decreasing pH values. Aerobically, this effect was weak, and the two strains were affected to the same degree. Under anaerobic conditions, the growth rates were markedly inhibited at a low pH, and the mutant was slightly more affected than the wild type. Levels of alcohol dehydrogenase were low under all conditions, indicating that the enzyme plays no role during exponential growth. The levels of diacetyl (acetoin) reductase, lactate dehydrogenase, and phosphotransacetylase were independent of the pH during aerobic growth of the two strains. Under anaerobic conditions, the formation of diacetyl (acetoin) reductase was pH dependent, with much higher levels of the enzyme at pH 5.0 than at pH 7.0. Lactate dehydrogenase and phosphotransacetylase revealed the same pattern of pH-dependent formation in the mutant, but not in the wild type. PMID:239921

  11. Adhesive properties of Enterobacter sakazakii to human epithelial and brain microvascular endothelial cells

    Directory of Open Access Journals (Sweden)

    Pospischil Andreas

    2006-06-01

    Full Text Available Abstract Background Enterobacter sakazakii is an opportunistic pathogen that has been associated with sporadic cases and outbreaks causing meningitis, necrotizing enterocolitis and sepsis especially in neonates. However, up to now little is known about the mechanisms of pathogenicity in E. sakazakii. A necessary state in the successful colonization, establishment and ultimately production of disease by microbial pathogens is the ability to adhere to host surfaces such as mucous membranes, gastric and intestinal epithelial or endothelial tissue. This study examined for the first time the adherence ability of 50 E. sakazakii strains to the two epithelial cell lines HEp-2 and Caco-2, as well as the brain microvascular endothelial cell line HBMEC. Furthermore, the effects of bacterial culture conditions on the adherence behaviour were investigated. An attempt was made to characterize the factors involved in adherence. Results Two distinctive adherence patterns, a diffuse adhesion and the formation of localized clusters of bacteria on the cell surface could be distinguished on all three cell lines. In some strains, a mixture of both patterns was observed. Adherence was maximal during late exponential phase, and increased with higher MOI. The adhesion capacity of E. sakazakii to HBMEC cells was affected by the addition of blood to the bacteria growth medium. Mannose, hemagglutination, trypsin digestion experiments and transmission electron microscopy suggested that the adhesion of E. sakazakii to the epithelial and endothelial cells is mainly non-fimbrial based. Conclusion Adherence experiments show heterogeneity within different E. sakazakii strains. In agreement with studies on E. cloacae, we found no relationship between the adhesive capacities in E. sakazakii and the eventual production of specific fimbriae. Further studies will have to be carried out in order to determine the adhesin(s involved in the interaction of E. sakazakii with cells and to

  12. Enterobacter and Klebsiella species isolated from fresh vegetables marketed in Valencia (Spain) and their clinically relevant resistances to chemotherapeutic agents.

    Science.gov (United States)

    Falomir, María Pilar; Rico, Hortensia; Gozalbo, Daniel

    2013-12-01

    Occurrence of antibiotic-resistant pathogenic or commensal enterobacteria in marketed agricultural foodstuffs may contribute to their incorporation into the food chain and constitutes an additional food safety concern. In this work, we have determined the clinically relevant resistances to 11 common chemotherapeutic agents in Enterobacter and Klebsiella isolates from fresh vegetables from various sources (supermarkets and greengrocers' shops in Valencia, Spain). A total of 96 isolates were obtained from 160 vegetables analyzed (50% positive samples): 68 Enterobacter isolates (59 E. cloacae, two E. aerogenes, two E. cancerogenus, one E. gergoviae, and four E. sakazakii, currently Cronobacter spp.), and 28 Klebsiella isolates (19 K. oxytoca and 9 K. pneumoniae). Only seven isolates were susceptible to all agents tested, and no resistances to ceftazidime, ciprofloxacin, gentamicin, and chloramphenicol were detected. Most isolates were resistant to amoxicillin/clavulanic acid (74 [58 Enterobacter and 16 Klebsiella]) or to ampicillin (80 [55/25]). Other resistances were less frequent: nitrofurantoin (13 isolates [12/1]), tetracycline (6 [5/1]), co-trimoxazole (3 [3/0]), cefotaxime (1 [1/0]), and streptomycin (2 [1/1]). Multiresistant isolates to two (56 [41/15]), three (10 E. cloacae isolates), four (one E. cloacae and one K. pneumoniae isolate), and five (two E. cloacae isolates) chemotherapeutic agents were also detected. The presence of potential pathogens points to marketed fresh produce, which often is eaten raw, as a risk factor for consumer health. In addition, these results support the usefulness of these bacterial species as indicators of the spreading of antibiotic resistances into the environment, particularly in the food chain, and suggest their role as carriers of resistance determinants from farms to consumers, which may constitute an additional "silent" food safety concern. Therefore, there is a need to improve the hygienic quality of marketed fresh

  13. Inactivation of Enterobacter sakazakii, Bacillus cereus, and Salmonella typhimurium in powdered weaning food by electron-beam irradiation

    Science.gov (United States)

    Hong, Yun-Hee; Park, Ji-Yong; Park, Jong-Hyun; Chung, Myong-Soo; Kwon, Ki-Sung; Chung, Kyungsook; Won, Misun; Song, Kyung-Bin

    2008-09-01

    Inactivation of Enterobacter sakazakii, Bacillus cereus, and Salmonella typhimurium were evaluated in powdered weaning food using electron-beam irradiation. E. sakazakii, B. cereus, and S. typhimurium were eliminated by irradiation at 16, 8, and 8 kGy, respectively. The D10-vlaues of E. sakazakii, B. cereus, and S. typhimurium inoculated on powdered weaning food were 4.83, 1.22, and 0.98 kGy, respectively. The results suggest that electron-beam irradiation should inhibit the growth of pathogenic bacteria on baby food without impairing qualities.

  14. Inactivation of Enterobacter sakazakii, Bacillus cereus, and Salmonella typhimurium in powdered weaning food by electron-beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Yun-Hee [Department of Food Science and Technology, College of Agriculture and Life Science, Chungnam National University, Yuseong-Gu, Daejeon 305-764 (Korea, Republic of); Park, Ji-Yong [Department of Biotechnology, Yonsei University, Seoul 120-749 (Korea, Republic of); Park, Jong-Hyun [Department of Food Science and Biotechnology, Kyungwon University, Sungnam 461-701 (Korea, Republic of); Chung, Myong-Soo [Department of Food Science, Ehwa Women' s University, Seoul 120-750 (Korea, Republic of); Kwon, Ki-Sung [Center for Food safety Evaluation, Korea Food and Drug Administration, Seoul 122-704 (Korea, Republic of); Chung, Kyungsook; Won, Misun [Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-333 (Korea, Republic of); Song, Kyung-Bin [Department of Food Science and Technology, College of Agriculture and Life Science, Chungnam National University, Yuseong-Gu, Daejeon 305-764 (Korea, Republic of)], E-mail: kbsong@cnu.ac.kr

    2008-09-15

    Inactivation of Enterobacter sakazakii, Bacillus cereus, and Salmonella typhimurium were evaluated in powdered weaning food using electron-beam irradiation. E. sakazakii, B. cereus, and S. typhimurium were eliminated by irradiation at 16, 8, and 8 kGy, respectively. The D{sub 10}-vlaues of E. sakazakii, B. cereus, and S. typhimurium inoculated on powdered weaning food were 4.83, 1.22, and 0.98 kGy, respectively. The results suggest that electron-beam irradiation should inhibit the growth of pathogenic bacteria on baby food without impairing qualities.

  15. Inactivation of Enterobacter sakazakii, Bacillus cereus, and Salmonella typhimurium in powdered weaning food by electron-beam irradiation

    International Nuclear Information System (INIS)

    Hong, Yun-Hee; Park, Ji-Yong; Park, Jong-Hyun; Chung, Myong-Soo; Kwon, Ki-Sung; Chung, Kyungsook; Won, Misun; Song, Kyung-Bin

    2008-01-01

    Inactivation of Enterobacter sakazakii, Bacillus cereus, and Salmonella typhimurium were evaluated in powdered weaning food using electron-beam irradiation. E. sakazakii, B. cereus, and S. typhimurium were eliminated by irradiation at 16, 8, and 8 kGy, respectively. The D 10 -vlaues of E. sakazakii, B. cereus, and S. typhimurium inoculated on powdered weaning food were 4.83, 1.22, and 0.98 kGy, respectively. The results suggest that electron-beam irradiation should inhibit the growth of pathogenic bacteria on baby food without impairing qualities

  16. Cryptosporidium sp. in lizards

    Czech Academy of Sciences Publication Activity Database

    Koudela, Břetislav; Modrý, D.

    1998-01-01

    Roč. 45, č. 1 (1998), s. 8 ISSN 1066-5234. [Cryptosporidium sp. in lazards. 01.01.1998-02.01.1998, Praha] R&D Projects: GA ČR GA508/95/0273; GA AV ČR IPP2020702 Subject RIV: fp - Other Medical Disciplines

  17. Endophytic Colonization and In Planta Nitrogen Fixation by a Herbaspirillum sp. Isolated from Wild Rice Species

    Science.gov (United States)

    Elbeltagy, Adel; Nishioka, Kiyo; Sato, Tadashi; Suzuki, Hisa; Ye, Bin; Hamada, Toru; Isawa, Tsuyoshi; Mitsui, Hisayuki; Minamisawa, Kiwamu

    2001-01-01

    Nitrogen-fixing bacteria were isolated from the stems of wild and cultivated rice on a modified Rennie medium. Based on 16S ribosomal DNA (rDNA) sequences, the diazotrophic isolates were phylogenetically close to four genera: Herbaspirillum, Ideonella, Enterobacter, and Azospirillum. Phenotypic properties and signature sequences of 16S rDNA indicated that three isolates (B65, B501, and B512) belong to the Herbaspirillum genus. To examine whether Herbaspirillum sp. strain B501 isolated from wild rice, Oryza officinalis, endophytically colonizes rice plants, the gfp gene encoding green fluorescent protein (GFP) was introduced into the bacteria. Observations by fluorescence stereomicroscopy showed that the GFP-tagged bacteria colonized shoots and seeds of aseptically grown seedlings of the original wild rice after inoculation of the seeds. Conversely, for cultivated rice Oryza sativa, no GFP fluorescence was observed for shoots and only weak signals were observed for seeds. Observations by fluorescence and electron microscopy revealed that Herbaspirillum sp. strain B501 colonized mainly intercellular spaces in the leaves of wild rice. Colony counts of surface-sterilized rice seedlings inoculated with the GFP-tagged bacteria indicated significantly more bacterial populations inside the original wild rice than in cultivated rice varieties. Moreover, after bacterial inoculation, in planta nitrogen fixation in young seedlings of wild rice, O. officinalis, was detected by the acetylene reduction and 15N2 gas incorporation assays. Therefore, we conclude that Herbaspirillum sp. strain B501 is a diazotrophic endophyte compatible with wild rice, particularly O. officinalis. PMID:11679357

  18. Enterobacter gergoviae membrane modifications are involved in the adaptive response to preservatives used in cosmetic industry.

    Science.gov (United States)

    Périamé, Marina; Pagès, Jean-Marie; Davin-Regli, Anne

    2015-01-01

    The objective of this study was to understand the adaptive mechanisms in Enterobacter gergoviae which are involved in recurrent contaminations in cosmetic products that are incorporated with preservatives. Bacterial strains from two backgrounds were examined for a profound understanding of the mechanisms of adaptation against preservatives. It included a series of Ent. gergoviae strain-ATCC 33028 derivatives, isolated using increasing methylisothiazolinone-chloromethylisothiazolinone (MIT-CMIT) and triclosan concentrations. The other series was of Ent. gergoviae isolates from cosmetic products exhibiting MIT-CMIT and triclosan resistance. We evaluated the outer membrane protein modifications and efflux mechanisms activities responsible for the resistant trait via immunoblotting assays. Additionally, for understanding the efflux activity real-time efflux, experiments were performed. A cross-insusceptibility between preservatives and some disinfectants was observed in MIT-CMIT-resistant derivative isolates, but antibiotics susceptibility was not altered. Resistance to EDTA was significant in all preservatives insusceptible derivative strains, indicating modifications in the LPS layer. Furthermore, an array of real-time efflux assays indicated different activity levels while no variations were detected in porins and AcrAB-TolC pumps production. Overexpression of a specific flagellin-type protein was observed in one of the MIT-CMIT- and triclosan-resistant strains. Another candidate, a 25-kDa peroxiredoxin enzyme involved in oxidative detoxification, was identified to be overexpressed in MIT-CMIT derivative. A similar profile was also observed among strains isolated from cosmetic products. Our study highlights the existence of adaptive mechanisms such as overexpression of detoxifying enzymes, flagellin, modification of membrane structure/function in Ent. gergoviae. They might be involved in recurrent episodes of contaminations occurring in the cosmetic production

  19. Impact of probiotic drugs, based on Enterobacter faecium autostrains, on human intestinal microflora in confined habitat

    Science.gov (United States)

    Viacheslav, Ilyin; Batov, Alexey; Usanova, Nonna

    The aim of research: Investigation of influence of probiotic drugs based on autostrains of Enter-obacter faecium, selected from the crew in long term isolation experiment in confined habitat. It is known that during long-term presence in confined habitat the risk of infectious diseases increases. One of the main infectious risk occurs during first 20 days of isolation as a result of exchange of strains and stress-mediated disbacterioses. Therefore it is necessary to evaluate activities of probiotics to avoid this risk. Furthermore, in case of super long term autonomous flight there should be possibilities of application of autochthonous microflora strains as pro-biotics to strengthen colonial resistance of crews. Materials and methods: In the experiment there were used probiotic drugs based on autostrains of E. faecium, selected from the crew before the experiment. Probiotic drugs were consumed during 30 days since the beginning of the experiment with the break of consumption between 10th to 19th day. Results: Comparing the state of intestinal microflora of the crew on the baseline and 14th day of experiment re-vealed remarkable changes of microflora: the increasing of concentration of bifidobacteria and E. faecium (approximately 10 times), elimination of hemolytic streptococcus, yeasts, reduction of the rate of S.aureus, hemolytic gramnegative non-fermenting rods, lactobacilli and normal E.coli. On the 45th day of isolation, 15 days after finishing of auto-strains administration, there fere signs of restoration of disbacteriosis: the quantitative decreasing lactobacilli, bifidobacteria and normal E.coli, increasing of the rate of S.aureus, hemolytic gramnegative nonfermentive rods. Conclusion: Thus we managed to avoid risk of pathogenicity potential growth in first 2 decades of isolation. Application of probiotic, based on the autostrains of E. faecium leads to insignificant changes of concentration of lactobacteries, bifidobacteries, normal E. coli and to

  20. Micro-aerobic, anaerobic and two-stage condition for ethanol production by Enterobacter aerogenes from biodiesel-derived crude glycerol

    DEFF Research Database (Denmark)

    Saisaard, Kanokrat; Angelidaki, Irini; Prasertsan, Poonsuk

    2011-01-01

    The microbial production of ethanol from biodiesel-derived crude glycerol by Enterobacter aerogenes TISTR1468, under micro-aerobic and anaerobic conditions, was investigated. The experimental results showed that micro-aerobic conditions were more favorable for cellular growth (4.0 g/L DCW), ethanol...

  1. Changes in qnr Prevalence and Fluoroquinolone Resistance in Clinical Isolates of Klebsiella pneumoniae and Enterobacter spp. Collected from 1990 to 2005▿

    Science.gov (United States)

    Strahilevitz, Jacob; Engelstein, Dalia; Adler, Amos; Temper, Violeta; Moses, Allon E.; Block, Colin; Robicsek, Ari

    2007-01-01

    Clinical isolates of Klebsiella pneumoniae and Enterobacter spp. collected from 1990 through 2005 at a tertiary care center were studied for qnr genes. Isolates bearing these genes emerged in the mid-1990s, coinciding with the time of a rapid increase in fluoroquinolone resistance. Sixty percent of these isolates were ciprofloxacin susceptible by CLSI breakpoints. PMID:17526754

  2. Occurrence and analysis of irp2 virulence gene in isolates of Klebsiella pneumoniae and Enterobacter spp. from microbiota and hospital and community-acquired infections.

    Science.gov (United States)

    Souza Lopes, Ana Catarina; Rodrigues, Juliana Falcão; Cabral, Adriane Borges; da Silva, Maíra Espíndola; Leal, Nilma Cintra; da Silveira, Vera Magalhães; de Morais Júnior, Marcos Antônio

    2016-07-01

    Eighty-five isolates of Klebsiella pneumoniae and Enterobacter spp., originating from hospital- and community-acquired infections and from oropharyngeal and faecal microbiota from patients in Recife-PE, Brazil, were analyzed regarding the presence of irp2 gene. This is a Yersinia typical gene involved in the synthesis of siderophore yersiniabactin. DNA sequencing confirmed the identity of irp2 gene in five K. pneumoniae, five Enterobacter aerogenes and one Enterobacter amnigenus isolates. To our knowledge in the current literature, this is the first report of the irp2 gene in E. amnigenus, a species considered an unusual human pathogen, and in K. pneumoniae and E. aerogenes isolates from the normal microbiota and from community infections, respectively. Additionally, the analyses of nucleotide and amino acid sequences suggest the irp2 genes derived from isolates used in this study are more closely related to that of Yersinia pestis P.CE882 than to that of Yersinia enterocolitica 8081. These data demonstrated that K. pneumoniae and Enterobacter spp. from normal microbiota and from community- and hospital-acquired infections possess virulence factors important for the establishment of extra-intestinal infections. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Enterobacter cloacae Complex Isolates Harboring blaNMC-A or blaIMI-Type Class A Carbapenemase Genes on Novel Chromosomal Integrative Elements and Plasmids.

    Science.gov (United States)

    Boyd, David A; Mataseje, Laura F; Davidson, Ross; Delport, Johannes A; Fuller, Jeff; Hoang, Linda; Lefebvre, Brigitte; Levett, Paul N; Roscoe, Diane L; Willey, Barbara M; Mulvey, Michael R

    2017-05-01

    Carbapenem-resistant Enterobacter cloacae complex isolates submitted to a reference laboratory from 2010 to 2015 were screened by PCR for seven common carbapenemase gene groups, namely, KPC, NDM, OXA-48, VIM, IMP, GES, and NMC-A/IMI. Nineteen of the submitted isolates (1.7%) were found to harbor Ambler class A bla NMC-A or bla IMI -type carbapenemases. All 19 isolates were resistant to at least one carbapenem but susceptible to aminoglycosides, trimethoprim-sulfamethoxazole, tigecycline, and ciprofloxacin. Most isolates (17/19) gave positive results with the Carba-NP test for phenotypic carbapenemase detection. Isolates were genetically diverse by pulsed-field gel electrophoresis macrorestriction analysis, multilocus sequence typing, and hsp60 gene analysis. The genes were found in various Enterobacter cloacae complex species; however, bla NMC-A was highly associated with Enterobacter ludwigii Whole-genome sequencing and bioinformatics analysis revealed that all NMC-A ( n = 10), IMI-1 ( n = 5), and IMI-9 ( n = 2) producers harbored the carbapenemase gene on EludIMEX-1-like integrative mobile elements (EcloIMEXs) located in the identical chromosomal locus. Two novel genes, bla IMI-5 and bla IMI-6 , were harbored on different IncFII-type plasmids. Enterobacter cloacae complex isolates harboring bla NMC-A/IMI -type carbapenemases are relatively rare in Canada. Though mostly found integrated into the chromosome, some variants are located on plasmids that may enhance their mobility potential. © Crown copyright 2017.

  4. Prevalence and impact of extended-spectrum β-lactamase production on clinical outcomes in cancer patients with Enterobacter species bacteremia.

    Science.gov (United States)

    Kim, Sun Jong; Park, Ki-Ho; Chung, Jin-Won; Sung, Heungsup; Choi, Seong-Ho; Choi, Sang-Ho

    2014-09-01

    We examined the prevalence of extended-spectrum β-lactamase (ESBL) production and the impact of ESBL on clinical outcomes in cancer patients with Enterobacter spp. bacteremia. Using prospective cohort data on Enterobacter bacteremia obtained between January 2005 and November 2008 from a tertiary care center, the prevalence and clinical impact of ESBL production were evaluated. Two-hundred and three episodes of Enterobacter spp. bacteremia were identified. Thirty-one blood isolates (15.3%, 31/203) scored positive by the double-disk synergy test. Among 17 isolates in which ESBL genes were detected by polymerase chain reaction and sequencing, CTX-M (n = 12), SHV-12 (n = 11), and TEM (n = 4) were the most prevalent ESBL types. Prior usage of antimicrobial agents (77.4% vs. 54.0%, p = 0.02) and inappropriate empirical antimicrobial therapy (22.6% vs. 3.0%, p Enterobacter bacteremia. Although inappropriate empirical therapy was more common in the ESBL-positive group, ESBL production was not associated with poorer outcomes.

  5. Role of ceftazidime dose regimen on the selection of resistant Enterobacter cloacae in the intestinal flora of rats treated for an experimental pulmonary infection

    NARCIS (Netherlands)

    W.H.F. Goessens (Wil); J.W. Mouton (Johan); M.T. ten Kate (Marian); A.J. Bijl; A. Ott (Alewijn); I.A.J.M. Bakker-Woudenberg (Irma)

    2007-01-01

    textabstractObjectives: The effect of ceftazidime dosing increments and frequency of dosing on the selection of ceftazidime-resistant Enterobacter cloacae in the intestine was studied in rats, during treatment of a pulmonary infection caused by Klebsiella pneumoniae. Methods: Rats with pulmonary

  6. Initial search for triggered gamma emission from Hf-178(m2) using the YSU miniball array

    Czech Academy of Sciences Publication Activity Database

    Carroll, J. J.; Burnett, J.; Drummond, T.; Lepak, J.; Propri, R.; Smith, D.; Karamian, S. A.; Adam, Jindřich; Stedile, F.; Agee, FJ.

    2002-01-01

    Roč. 143, 1, 2, 3, 4 (2002), s. 37-54 ISSN 0304-3843 Institutional research plan: CEZ:AV0Z1048901 Keywords : triggered gamma emission * Hf-178(m2) * nuclear batteries Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 0.533, year: 2002

  7. Q-PCR Based Culture-Independent Enumeration and Detection of Enterobacter: An Emerging Environmental Human Pathogen in Riverine Systems and Potable Water

    Science.gov (United States)

    Patel, Chandra B.; Shanker, Rishi; Gupta, Vijai K.; Upadhyay, Ram S.

    2016-01-01

    The availability of safe and pristine water is a global challenge when large numbers of natural and anthropogenic water resources are being depleted with faster rate. The remaining water resources are severely contaminated with various kinds of contaminants including microorganisms. Enterobacter is one of the fecal coliform bacteria of family Enterobacteriaceae. Enterobacter was earlier used as an indicator bacterium along with other fecal Coliforms namely Escherichia coli, Citrobacter, and Klebsiella, but it is now known to cause various diseases in human beings. In this study, we have collected 55 samples from potable water and riverine system and proved their presence using their conserved sequences of 16S rRNA and 23S rRNA genes with the help of SYBR green real-time PCR, which showed very high specificity for the detection of Enterobacter. The Enterobacter counts in potable water were found to 1290 ± 32.89 to 1460 ± 39.42 cfu/100 ml. The Enterobacter levels in surface water were 1.76 × 104 ± 492, 1.33 × 104 ± 334, 1.15 × 104 ± 308, 2.56 × 104 ± 802, 2.89 × 104 ± 962, 8.16 × 104 ± 3443 cfu/100 ml; the levels of Enterobacter contamination associated with hydrophytes were 4.80 × 104 ± 1804, 3.48 × 104 ± 856, 8.50 × 104 ± 2074, 8.09 × 104 ± 1724, 6.30 × 104 ± 1738, 3.68 × 104 ± 949 cfu/10 g and the Enterobacter counts in sediments of the river, were 2.36 × 104 ± 703, 1.98 × 104 ± 530, 9.92 × 104 ± 3839, 6.80 × 104 ± 2230, 8.76 × 104 ± 3066 and 2.34 × 104 ± 732 cfu/10 g at the sampling Site #1, Site #2, Site #3, Site #4, Site #5, and Site #6, respectively. The assay could be used for the regular monitoring of potable water and other water reservoirs to check waterborne outbreaks. PMID:26925044

  8. Ethylene induced plant stress tolerance by Enterobacter sp. SA187 is mediated by 2‐keto‐4‐methylthiobutyric acid production

    KAUST Repository

    Zé licourt, Axel de; Synek, Lukas; Saad, Maged; Alzubaidy, Hanin S.; Jalal, Rewaa Sauod Mohammed; Xie, Yakun; Andres-Barrao, Cristina; Rolli, Eleonora; Guerard, Florence; Mariappan, Kiruthiga; Daur, Ihsanullah; Colcombet, Jean; Benhamed, Moussa; Depaepe, Thomas; Van Der Straeten, Dominique; Hirt, Heribert

    2018-01-01

    of mechanisms related to the beneficial association of SA187 with plants. SA187 colonizes both the surface and inner tissues of Arabidopsis roots and shoots. SA187 induces salt stress tolerance by production of bacterial 2-keto-4-methylthiobutyric acid (KMBA

  9. IAA Producing Enterobacter sp. I-3 as a Potent Bio-herbicide Candidate for Weed Control: A Special Reference with Lettuce Growth Inhibition

    OpenAIRE

    Park, Jae-Man; Radhakrishnan, Ramalingam; Kang, Sang-Mo; Lee, In-Jung

    2015-01-01

    Development of bio-herbicides is an emerging method to weed management in agricultural field. Very few studies were conducted on identification of microbial bio-herbicides to weed control. The present study was aimed to isolate and identify the effective bio-herbicide potential bacterium from soil and assess their role on plant growth inhibition. Three-hundred and one rhizobacteria were isolated from agriculture field soil samples collected from various parts of Republic of Korea. Two bacteri...

  10. Control of Branchionus sp. and Amoeba sp. in cultures of Arthrospira sp. Control de Branchionus sp. y Amoeba sp. en cultivos de Arthrospira sp.

    Directory of Open Access Journals (Sweden)

    Carlos Méndez

    2012-09-01

    Full Text Available Cultivation of cyanobacterium Arthrospira sp. has been developed in many countries for the production of proteins, pigments and other compounds. Outdoor mass cultures are often affected by biological contamination, drastically reducing productivity as far as bringing death. This study evaluates the control of Branchionus sp. and Amoeba sp. with two chemical compounds: urea (U and ammonium bicarbonate (AB, in laboratory conditions and outdoor mass culture of Arthrospira sp. The lethal concentration 100 (LC100 at 24 h for Branchionus sp. and Amoeba sp. determined was of 60-80 mg L-1 (U and 100-150 mg L-1 (AB. The average effective inhibition concentration for 50% of the population (IC50 in Arthrospira sp., after 72 h, was 80 mg L-1 (U and 150 mg L-1 (AB. The application of doses of 60 mg L-1 (U or 100 mg L-1 (AB in the outdoor mass culture of this contaminated microalga, completely inhibited grazing and did not affect the growth of Arthrospira sp. but rather promoted rapid recovery of algal density at levels prior to infestation. These compounds provided an economical and effective control of predators in cultures of Arthrospira sp.El cultivo de la cianobacteria Arthrospira sp. ha sido desarrollado en muchos países para la obtención de proteínas, pigmentos y otros compuestos. Cultivo que a nivel industrial se ve afectado frecuentemente por contaminación biológica, reduciendo drásticamente la productividad hasta causar la muerte. Este estudio evalúa el control de Branchionus sp. y de Amoeba sp. con dos compuestos químicos, la urea (U y bicarbonato de amonio (AB en cultivos de Arthrospira sp. La concentración letal 100 (LC100 determinada a las 24 h para Branchionus sp. y Amoeba sp. fue de 60-80 mg L-1 (U y 100-150 mg L-1 (AB. La concentración media de inhibición efectiva, después de 72 h, para el 50% de la población (IC50 en Arthrospira fue de 80 mg L-1 (U y 150 mg L-1 (AB. La aplicación de dosis de 60 mg L-1 (U ó 100 mg L-1 (AB en

  11. Metabolic and Co-Metabolic Transformation of Diclofenac by Enterobacter hormaechei D15 Isolated from Activated Sludge.

    Science.gov (United States)

    Aissaoui, Salima; Ouled-Haddar, Houria; Sifour, Mohamed; Harrouche, Kamel; Sghaier, Haitham

    2017-03-01

    The presence of non-steroidal anti-inflammatory drugs, such as diclofenac (DCF), in the environment, is an emerging problem due to their harmful effects on non-target organisms, even at low concentrations. We studied the biodegradation of DCF by the strain D15 of Enterobacter hormaechei. The strain was isolated from an activated sludge, and identified as E. hormaechei based on its physiological characteristics and its 16 S RNA sequence. Using HPTLC and GC-MS methods, we demonstrated that this strain metabolized DCF at an elimination rate of 52.8%. In the presence of an external carbon source (glucose), the elimination rate increased to approximately 82%. GC-MS analysis detected and identified one metabolite as 1-(2,6-dichlorophenyl)-1,3-dihydro-2H-indol-2-one; it was produced as a consequence of dehydration and lactam formation reactions.

  12. A Comparison of Molecular Typing Methods Applied to Enterobacter cloacae complex: hsp60 Sequencing, Rep-PCR, and MLST

    Directory of Open Access Journals (Sweden)

    Roberto Viau

    2017-02-01

    Full Text Available Molecular typing using repetitive sequenced-based PCR (rep-PCR and hsp60 sequencing were applied to a collection of diverse Enterobacter cloacae complex isolates. To determine the most practical method for reference laboratories, we analyzed 71 E. cloacae complex isolates from sporadic and outbreak occurrences originating from 4 geographic areas. While rep-PCR was more discriminating, hsp60 sequencing provided a broader and a more objective geographical tracking method similar to multilocus sequence typing (MLST. In addition, we suggest that MLST may have higher discriminative power compared to hsp60 sequencing, although rep-PCR remains the most discriminative method for local outbreak investigations. In addition, rep-PCR can be an effective and inexpensive method for local outbreak investigation.

  13. Cloning and characterization of the ddc homolog encoding L-2,4-diaminobutyrate decarboxylase in Enterobacter aerogenes.

    Science.gov (United States)

    Yamamoto, S; Mutoh, N; Tsuzuki, D; Ikai, H; Nakao, H; Shinoda, S; Narimatsu, S; Miyoshi, S I

    2000-05-01

    L-2,4-diaminobutyrate decarboxylase (DABA DC) catalyzes the formation of 1,3-diaminopropane (DAP) from DABA. In the present study, the ddc gene encoding DABA DC from Enterobacter aerogenes ATCC 13048 was cloned and characterized. Determination of the nucleotide sequence revealed an open reading frame of 1470 bp encoding a 53659-Da protein of 490 amino acids, whose deduced NH2-terminal sequence was identical to that of purified DABA DC from E. aerogenes. The deduced amino acid sequence was highly similar to those of Acinetobacter baumannii and Haemophilus influenzae DABA DCs encoded by the ddc genes. The lysine-307 of the E. aerogenes DABA DC was identified as the pyridoxal 5'-phosphate binding residue by site-directed mutagenesis. Furthermore, PCR analysis revealed the distribution of E. aerogenes ddc homologs in some other species of Enterobacteriaceae. Such a relatively wide occurrence of the ddc homologs implies biological significance of DABA DC and its product DAP.

  14. SP mountain data analysis

    Science.gov (United States)

    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.

  15. BACTÉRIAS ENTÉRICAS NAS MÃOS DE MANIPULADORES DE ALIMENTOS DA CIDADE DE ARARAQUARA – SP

    Directory of Open Access Journals (Sweden)

    Clarice Queico Fugimura Leite

    2007-02-01

    Full Text Available Pesquisou-se a presença de bactérias entéricas nas mãos de 48 manipuladores de alimentos de estabelecimentos comerciais da cidade de Araraquara – SP. Verificou-se ausência de Salmonella, Shigella, Yersinia enterocolitica e Escherichia coli enteropatogênica utilizando-se as técnicas propostas. Dos indivíduos analisados 97,9% (47 carreavam outras enterobactérias e 95,8% (46 Streptococcus do grupo D (enterococo. A diversidade da flora bacteriana encontrada evidencia o risco potencial representado pelas mãos na transmissão das infecções alimentares.

  16. SP-100 Test Site

    International Nuclear Information System (INIS)

    Cox, C.M.; Mahaffey, M.K.; Miller, W.C.

    1988-01-01

    Preparatory activities are well under way at Hanford to convert the 309 Containment Building and its associated service wing to a 2.5 MWt nuclear test facility for the SP-100 Ground Engineering System (GES) test. Preliminary design is complete, encompassing facility modifications, a secondary heat transport system, a large vacuum system to enclose the high temperature reactor, a test assembly cell and handling system, control and data processing systems, and safety and auxiliary systems. The design makes extensive use of existing equipment to minimize technical risk and cost. Refurbishment of this equipment is 75% complete. The facility has been cleared of obstructing equipment from its earlier reactor test. Current activities are focusing on definitive design and preparation of the Preliminary Safety Analysis Report (PSAR) aimed at procurement and construction approvals and schedules to achieve reactor criticality by January 1992. 6 refs

  17. Multidrug-Resistant CTX-M-(15, 9, 2)- and KPC-2-Producing Enterobacter hormaechei and Enterobacter asburiae Isolates Possessed a Set of Acquired Heavy Metal Tolerance Genes Including a Chromosomal sil Operon (for Acquired Silver Resistance).

    Science.gov (United States)

    Andrade, Leonardo N; Siqueira, Thiago E S; Martinez, Roberto; Darini, Ana Lucia C

    2018-01-01

    Bacterial resistance to antibiotics is concern in healthcare-associated infections. On the other hand, bacterial tolerance to other antimicrobials, like heavy metals, has been neglected and underestimated in hospital pathogens. Silver has long been used as an antimicrobial agent and it seems to be an important indicator of heavy metal tolerance. To explore this perspective, we searched for the presence of acquired silver resistance genes ( sil operon: silE, silS, silR, silC, silF, silB, silA , and silP ) and acquired extended-spectrum cephalosporin and carbapenem resistance genes ( bla CTX-M and bla KPC ) in Enterobacter cloacae Complex (EcC) ( n = 27) and Enterobacter aerogenes ( n = 8) isolated from inpatients at a general hospital. Moreover, the genetic background of the silA (silver-efflux pump) and the presence of other acquired heavy metal tolerance genes, pcoD (copper-efflux pump), arsB (arsenite-efflux pump), terF (tellurite resistance protein), and merA (mercuric reductase) were also investigated. Outstandingly, 21/27 (78%) EcC isolates harbored silA gene located in the chromosome. Complete sil operon was found in 19/21 silA -positive EcC isolates. Interestingly, 8/20 (40%) E. hormaechei and 5/6 (83%) E. asburiae co-harbored silA/pcoD genes and bla CTX-M-(15,2,or9) and/or bla KPC-2 genes. Frequent occurrences of arsB, terF , and merA genes were detected, especially in silA/pcoD -positive, multidrug-resistant (MDR) and/or CTX-M-producing isolates. Our study showed co-presence of antibiotic and heavy metal tolerance genes in MDR EcC isolates. In our viewpoint, there are few studies regarding to bacterial heavy metal tolerance and we call attention for more investigations and discussion about this issue in different hospital pathogens.

  18. Multidrug-Resistant CTX-M-(15, 9, 2- and KPC-2-Producing Enterobacter hormaechei and Enterobacter asburiae Isolates Possessed a Set of Acquired Heavy Metal Tolerance Genes Including a Chromosomal sil Operon (for Acquired Silver Resistance

    Directory of Open Access Journals (Sweden)

    Leonardo N. Andrade

    2018-03-01

    Full Text Available Bacterial resistance to antibiotics is concern in healthcare-associated infections. On the other hand, bacterial tolerance to other antimicrobials, like heavy metals, has been neglected and underestimated in hospital pathogens. Silver has long been used as an antimicrobial agent and it seems to be an important indicator of heavy metal tolerance. To explore this perspective, we searched for the presence of acquired silver resistance genes (sil operon: silE, silS, silR, silC, silF, silB, silA, and silP and acquired extended-spectrum cephalosporin and carbapenem resistance genes (blaCTX−M and blaKPC in Enterobacter cloacae Complex (EcC (n = 27 and Enterobacter aerogenes (n = 8 isolated from inpatients at a general hospital. Moreover, the genetic background of the silA (silver-efflux pump and the presence of other acquired heavy metal tolerance genes, pcoD (copper-efflux pump, arsB (arsenite-efflux pump, terF (tellurite resistance protein, and merA (mercuric reductase were also investigated. Outstandingly, 21/27 (78% EcC isolates harbored silA gene located in the chromosome. Complete sil operon was found in 19/21 silA-positive EcC isolates. Interestingly, 8/20 (40% E. hormaechei and 5/6 (83% E. asburiae co-harbored silA/pcoD genes and blaCTX−M−(15,2,or9 and/or blaKPC−2 genes. Frequent occurrences of arsB, terF, and merA genes were detected, especially in silA/pcoD-positive, multidrug-resistant (MDR and/or CTX-M-producing isolates. Our study showed co-presence of antibiotic and heavy metal tolerance genes in MDR EcC isolates. In our viewpoint, there are few studies regarding to bacterial heavy metal tolerance and we call attention for more investigations and discussion about this issue in different hospital pathogens.

  19. High prevalence of non-clonal imipenem-nonsusceptible Enterobacter spp. isolates in Korea and their association with porin down-regulation.

    Science.gov (United States)

    Lee, Ji-Young; Hong, Yoon-Kyoung; Lee, Haejeong; Ko, Kwan Soo

    2017-01-01

    We investigated the prevalence and clonal distribution of imipenem-nonsusceptible Enterobacter clinical isolates from hospitals in Korea and the contributions of various mechanisms to imipenem nonsusceptibility. The in vitro antimicrobial susceptibility to imipenem of 357 non-duplicated Enterobacter isolates obtained from eight geographically distant tertiary care hospitals in Korea was evaluated. Imipenem-nonsusceptible Enterobacter isolates were genotyped. Additionally, β-lactamase genes were screened using PCR, and the expression of efflux pump and porin genes was investigated using quantitative RT-PCR. A total of 31 isolates (8.7%) were not susceptible to imipenem. Clonal diversity of 17 imipenem-nonsusceptible E. cloacae isolates was demonstrated by multilocus sequence typing. Fourteen imipenem-nonsusceptible E. aerogenes isolates were found to be distantly genetically related by an ERIC-PCR analysis. Expression levels of porin ompD and ompK35 genes were decreased in all imipenem-nonsusceptible E. cloacae and E. aerogenes isolates. However, only two isolates were found positive for bla IMP and bla VIM genes, and expression of the efflux pump gene, acrB, was not associated with reduced imipenem susceptibility. Imipenem resistance seems to have occurred independently in most of the imipenem-nonsusceptible isolates in this study, and decreased porin expression was found to be the main mechanism underlying this reduced susceptibility to imipenem. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Bradysia sp. em morangueiro Bradysia sp. in strawberry

    Directory of Open Access Journals (Sweden)

    Bernadete Radin

    2009-04-01

    Full Text Available No trabalho, relatam-se os primeiros registros de Bradysia sp. (Insecta: Diptera: Sciaridae em morangueiro (Fragaria x ananassa Duch., cultivado no Município de Eldorado do Sul, RS. O cultivo foi realizado em sacolas com três metros de comprimento, preenchidas com substrato composto de casca de arroz e turfa, dispostas horizontalmente sobre bancadas de madeira, em ambiente protegido. A presença de Bradysia sp. foi observada na segunda quinzena de agosto de 2005. Neste trabalho, estão descritos os sintomas apresentados no morangueiro pela praga, prováveis conseqüências sobre o aparecimento de doenças e uma breve descrição morfológica da Bradysia sp., adulto e fase larval.This paper describes the first record of Bradysia sp. (Insecta; Diptera; Sciaridae in strawberry (Fragaria x ananassa, cultivated in the city of Eldorado do Sul, RS, Brazil. Strawberry was planted in plastic bags filled with a mixture of burnt rice hulls and peat and cultivated in a greenhouse. The presence of Bradysia sp was noticed in the second fortnight of August, 2005. The symptoms in strawberry and the probable consequences in terms of disease arising were described in the present study, as well as the morphological characterization of Bradysia sp. and its illustrations.

  1. Yersinia pekkanenii sp. nov.

    Science.gov (United States)

    Murros-Kontiainen, Anna; Johansson, Per; Niskanen, Taina; Fredriksson-Ahomaa, Maria; Korkeala, Hannu; Björkroth, Johanna

    2011-10-01

    The taxonomic position of three strains from water, soil and lettuce samples was studied by using a polyphasic taxonomic approach. The strains were reported to lack the virulence-encoding genes inv and virF in a previous study. Controversially, API 20 E and some other phenotypic tests suggested that the strains belong to Yersinia pseudotuberculosis, which prompted this polyphasic taxonomic study. In both the phylogenetic analyses of four housekeeping genes (glnA, gyrB, recA and HSP60) and numerical analyses of HindIII and EcoRI ribopatterns, the strains formed a separate group within the genus Yersinia. Analysis of the 16S rRNA gene sequences showed that the strains were related to Yersinia aldovae and Yersinia mollaretii, but DNA-DNA hybridization analysis differentiated them from these species. Based on the results of the phylogenetic and DNA-DNA hybridization analyses, a novel species, Yersinia pekkanenii sp. nov., is proposed. The type strain is ÅYV7.1KOH2(T) ( = DSM 22769(T)  = LMG 25369(T)).

  2. A Sequential Statistical Approach towards an Optimized Production of a Broad Spectrum Bacteriocin Substance from a Soil Bacterium Bacillus sp. YAS 1 Strain

    Directory of Open Access Journals (Sweden)

    Amira M. Embaby

    2014-01-01

    Full Text Available Bacteriocins, ribosomally synthesized antimicrobial peptides, display potential applications in agriculture, medicine, and industry. The present study highlights integral statistical optimization and partial characterization of a bacteriocin substance from a soil bacterium taxonomically affiliated as Bacillus sp. YAS 1 after biochemical and molecular identifications. A sequential statistical approach (Plackett-Burman and Box-Behnken was employed to optimize bacteriocin (BAC YAS 1 production. Using optimal levels of three key determinants (yeast extract (0.48% (w/v, incubation time (62 hrs, and agitation speed (207 rpm in peptone yeast beef based production medium resulted in 1.6-fold enhancement in BAC YAS 1 level (470 AU/mL arbitrary units against Erwinia amylovora. BAC YAS 1 showed activity over a wide range of pH (1–13 and temperature (45–80°C. A wide spectrum antimicrobial activity of BAC YAS 1 against the human pathogens (Clostridium perfringens, Staphylococcus epidermidis, Campylobacter jejuni, Enterobacter aerogenes, Enterococcus sp., Proteus sp., Klebsiella sp., and Salmonella typhimurium, the plant pathogen (E. amylovora, and the food spoiler (Listeria innocua was demonstrated. On top and above, BAC YAS 1 showed no antimicrobial activity towards lactic acid bacteria (Lactobacillus bulgaricus, L. casei, L. lactis, and L. reuteri. Promising characteristics of BAC YAS 1 prompt its commercialization for efficient utilization in several industries.

  3. Antimicrobial peptides from Capsicum sp.

    African Journals Online (AJOL)

    ajl yemi

    2011-12-30

    Dec 30, 2011 ... Key words: Antimicrobial peptides, Capsicum sp, Capsicum chinense, chili pepper, agronomical options, ..... of this human activity is resumed by the simple phrase: produce .... It will be interesting to scale the AMPs extraction.

  4. A novel immunosensor for Enterobacter sakazakii based on multiwalled carbon nanotube/ionic liquid/thionine modified electrode

    International Nuclear Information System (INIS)

    Zhang Xiao; Dou Wenchao; Zhan Xuejia; Zhao Guangying

    2012-01-01

    Highlights: ► Constructed a novel immunosensor using MWCNT/[BMIM]PF 6 /thionine for E. sakazakii. ► Optimum conditions for the detection of E. sakazakii were investigated. ► The properties of proposed immunosensor were studied by AFM and CVs. ► The biosensor exhibited good specificity, reproducibility, stability and accuracy. - Abstract: A novel immunosensor for Enterobacter sakazakii (E. sakazakii) based on screen-printed carbon electrode (SPCE) modified by multiwalled carbon nanotube (MWCNT), 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM]PF 6 ) and thionine (Thi) was developed for the first time. The surface morphologies of modified electrodes were characterized by means of atomic force microscope (AFM). The electrochemical performance of the immunosensor was evaluated by cyclic voltammetry. Horseradish peroxidase labeled antibody to E. sakazakii in [BMIM]PF 6 showed high activity and stability. Under optimal conditions, E. sakazakii could be detected in range of 10 3 –10 9 CFU/ml with detection limit of 7.7 × 10 1 CFU/ml. The proposed immunosensor exhibited excellent long-time storage stability and had potential use in clinical immunoassay of E. sakazakii.

  5. Conversion of cheese whey into a fucose- and glucuronic acid-rich extracellular polysaccharide by Enterobacter A47.

    Science.gov (United States)

    Antunes, Sílvia; Freitas, Filomena; Alves, Vítor D; Grandfils, Christian; Reis, Maria A M

    2015-09-20

    Cheese whey was used as the sole substrate for the production of extracellular polysaccharides (EPS) by Enterobacter A47. An EPS concentration of 6.40 g L(-1) was reached within 3.2 days of cultivation, corresponding to a volumetric productivity of 2.00 g L(-1) d(-1). The produced EPS was mainly composed of glucuronic acid (29 mol%) and fucose (29 mol%), with lower contents of glucose and galactose (21 mol% each) and a total acyl groups content of 32 wt.%. The polymer had an average molecular weight of 1.8×10(6) Da, with a polydispersity index of 1.2, and an intrinsic viscosity of 8.0 dL g(-1). EPS aqueous solutions (1.0 wt.% in 0.01 M NaCl, at pH 8.0) presented a shear thinning behavior with a viscosity of the first Newtonian plateau approaching 0.1 Pas. This novel glucuronic acid-rich polymer possesses interesting rheological properties, which, together with its high content of glucuronic acid and fucose, two bioactive sugar monomers, confers it a great potential for use in high-value applications, such as cosmetics and pharmaceuticals. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Antimicrobial activity evaluation and comparison of methods of susceptibility for Klebsiella pneumoniae carbapenemase (KPC)-producing Enterobacter spp. isolates.

    Science.gov (United States)

    Rechenchoski, Daniele Zendrini; Dambrozio, Angélica Marim Lopes; Vivan, Ana Carolina Polano; Schuroff, Paulo Alfonso; Burgos, Tatiane das Neves; Pelisson, Marsileni; Perugini, Marcia Regina Eches; Vespero, Eliana Carolina

    The production of KPC (Klebsiella pneumoniae carbapenemase) is the major mechanism of resistance to carbapenem agents in enterobacterias. In this context, forty KPC-producing Enterobacter spp. clinical isolates were studied. It was evaluated the activity of antimicrobial agents: polymyxin B, tigecycline, ertapenem, imipenem and meropenem, and was performed a comparison of the methodologies used to determine the susceptibility: broth microdilution, Etest ® (bioMérieux), Vitek 2 ® automated system (bioMérieux) and disc diffusion. It was calculated the minimum inhibitory concentration (MIC) for each antimicrobial and polymyxin B showed the lowest concentrations for broth microdilution. Errors also were calculated among the techniques, tigecycline and ertapenem were the antibiotics with the largest and the lower number of discrepancies, respectively. Moreover, Vitek 2 ® automated system was the method most similar compared to the broth microdilution. Therefore, is important to evaluate the performance of new methods in comparison to the reference method, broth microdilution. Copyright © 2017 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  7. Identification of regulated genes conferring resistance to high concentrations of glyphosate in a new strain of Enterobacter.

    Science.gov (United States)

    Fei, Yun-Yan; Gai, Jun-Yi; Zhao, Tuan-Jie

    2013-12-01

    Glyphosate is a widely used herbicide that inhibits 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) activity. Most plants and microbes are sensitive to glyphosate. However, transgenic-resistant crops that contain a modified epsps obtained from the resistant microbes have been commercially successful and therefore, new resistance genes and their adaptive regulatory mechanisms are of great interest. In this study, a soil-borne, glyphosate-resistant bacterium was selected and identified as Enterobacter. The EPSPS in this strain was found to have been altered to a resistant one. A total of 42 differentially expressed genes (DEGs) in the glyphosate were screened using microarray techniques. Under treatment, argF, sdhA, ivbL, rrfA-H were downregulated, whereas the transcripts of speA, osmY, pflB, ahpC, fusA, deoA, uxaC, rpoD and a few ribosomal protein genes were upregulated. Data were verified by quantitative real-time PCR on selected genes. All transcriptional changes appeared to protect the bacteria from glyphosate and associated osmotic, acidic and oxidative stresses. Many DEGs may have the potential to confer resistance to glyphosate alone, and some may be closely related to the shikimate pathway, reflecting the complex gene interaction network for glyphosate resistance. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  8. Severe community-acquired Enterobacter pneumonia: a plea for greater awareness of the concept of health-care-associated pneumonia

    Science.gov (United States)

    2011-01-01

    Background Patients with Enterobacter community-acquired pneumonia (EnCAP) were admitted to our intensive care unit (ICU). Our primary aim was to describe them as few data are available on EnCAP. A comparison with CAP due to common and typical bacteria was performed. Methods Baseline clinical, biological and radiographic characteristics, criteria for health-care-associated pneumonia (HCAP) were compared between each case of EnCAP and thirty age-matched typical CAP cases. A univariate and multivariate logistic regression analysis was performed to determine factors independently associated with ENCAP. Their outcome was also compared. Results In comparison with CAP due to common bacteria, a lower leukocytosis and constant HCAP criteria were associated with EnCAP. Empiric antibiotic therapy was less effective in EnCAP (20%) than in typical CAP (97%) (p < 0.01). A delay in the initiation of appropriate antibiotic therapy (3.3 ± 1.6 vs. 1.2 ± 0.6 days; p < 0.01) and an increase in duration of mechanical ventilation (8.4 ± 5.2 vs. 4.0 ± 4.3 days; p = 0.01) and ICU stay were observed in EnCAP patients. Conclusions EnCAP is a severe infection which is more consistent with HCAP than with typical CAP. This retrospectively suggests that the application of HCAP guidelines should have improved EnCAP management. PMID:21569334

  9. Screening and Characterization of Cold-Active β-Galactosidase Producing Psychrotrophic Enterobacter ludwigii from the Sediments of Arctic Fjord.

    Science.gov (United States)

    Alikkunju, Aneesa P; Sainjan, Neethu; Silvester, Reshma; Joseph, Ajith; Rahiman, Mujeeb; Antony, Ally C; Kumaran, Radhakrishnan C; Hatha, Mohamed

    2016-10-01

    Low-temperature-tolerant microorganisms and their cold-active enzymes could be an innovative and invaluable tool in various industrial applications. In the present study, bacterial isolates from the sediment samples of Kongsfjord, Norwegian Arctic, were screened for β-galactosidase production. Among the isolates, KS25, KS85, KS60, and KS92 have shown good potential in β-galactosidase production at 20 °C. 16SrRNA gene sequence analysis revealed the relatedness of the isolates to Enterobacter ludwigii. The optimum growth temperature of the isolate was 25 °C. The isolate exhibited good growth and enzyme production at a temperature range of 15-35 °C, pH 5-10. The isolate preferred yeast extract and lactose for the maximum growth and enzyme production at conditions of pH 7.0, temperature of 25 °C, and agitation speed of 100 rpm. The growth and enzyme production was stimulated by Mn 2+ and Mg 2+ and strongly inhibited by Zn 2+ , Ni 2+ , and Cu + . β-Galactosidases with high specific activity at low temperatures are very beneficial in food industry to compensate the nutritional problem associated with lactose intolerance. The isolate exhibited a remarkable capability to utilize clarified whey, an industrial pollutant, for good biomass and enzyme yield and hence could be well employed in whey bioremediation.

  10. Enterobacter asburiae KE17 association regulates physiological changes and mitigates the toxic effects of heavy metals in soybean.

    Science.gov (United States)

    Kang, S-M; Radhakrishnan, R; You, Y-H; Khan, A-L; Lee, K-E; Lee, J-D; Lee, I-J

    2015-09-01

    This study aimed to elucidate the role played by Enterobacter asburiae KE17 in the growth and metabolism of soybeans during copper (100 μm Cu) and zinc (100 μm Zn) toxicity. When compared to controls, plants grown under Cu and Zn stress exhibited significantly lower growth rates, but inoculation with E. asburiae KE17 increased growth rates of stressed plants. The concentrations of plant hormones (abscisic acid and salicylic acid) and rates of lipid peroxidation were higher in plants under heavy metal stress, while total chlorophyll, carotenoid content and total polyphenol concentration were lower. While the bacterial treatment reduced the abscisic acid and salicylic acid content and lipid peroxidation rate of Cu-stressed plants, it also increased the concentration of photosynthetic pigments and total polyphenol. Moreover, the heavy metals induced increased accumulation of free amino acids such as aspartic acid, threonine, serine, glycine, alanine, leucine, isoleucine, tyrosine, proline and gamma-aminobutyric acid, while E. asburiae KE17 significantly reduced concentrations of free amino acids in metal-affected plants. Co-treatment with E. asburiae KE17 regulated nutrient uptake by enhancing nitrogen content and inhibiting Cu and Zn accumulation in soybean plants. The results of this study suggest that E. asburiae KE17 mitigates the effects of Cu and Zn stress by reprogramming plant metabolic processes. © 2015 German Botanical Society and The Royal Botanical Society of the Netherlands.

  11. Production of FucoPol by Enterobacter A47 using waste tomato paste by-product as sole carbon source.

    Science.gov (United States)

    Antunes, Sílvia; Freitas, Filomena; Sevrin, Chantal; Grandfils, Christian; Reis, Maria A M

    2017-03-01

    Out-of-specification tomato paste, a by-product from the tomato processing industry, was used as the sole substrate for cultivation of the bacterium Enterobacter A47 and production of FucoPol, a value-added fucose-rich extracellular polysaccharide. Among the different tested fed-batch strategies, pH-stat, DO-stat and continuous substrate feeding, the highest production (8.77gL -1 ) and overall volumetric productivity (2.92gL -1 d -1 ) were obtained with continuous substrate feeding at a constant flow rate of 11gh -1 . The polymer produced had the typical FucoPol composition (37mol% fucose, 27mol% galactose, 23mol% glucose and 12mol% glucuronic acid, with an acyl groups content of 13wt%). The average molecular weight was 4.4×10 6 Da and the polydispersity index was 1.2. This study demonstrated that out-of-specification tomato paste is a suitable low-cost substrate for the production of FucoPol, thus providing a route for the valorization of this by-product into a high-value microbial product. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Multi-time series RNA-seq analysis of Enterobacter lignolyticus SCF1 during growth in lignin-amended medium

    Energy Technology Data Exchange (ETDEWEB)

    Orellana, Roberto; Chaput, Gina; Markillie, Lye Meng; Mitchell, Hugh; Gaffrey, Matt; Orr, Galya; DeAngelis, Kristen M.; Yang, Shihui

    2017-10-19

    The production of lignocellulosic-derived biofuels is a highly promising source of alternative energy, but it has been constrained by the lack of a microbial platform capable to efficiently degrade this recalcitrant material and cope with by-products that can be toxic to cells. Species that naturally grow in environments where carbon is mainly available as lignin are promising for finding new ways of removing the lignin that protects cellulose for improved conversion of lignin to fuel precursors. Enterobacter lignolyticus SCF1 is a facultative anaerobic Gammaproteobacteria isolated from tropical rain forest soil collected in El Yunque forest, Puerto Rico under anoxic growth conditions with lignin as sole carbon source. Whole transcriptome analysis of SCF1 during E.lignolyticus SCF1 lignin degradation was conducted on cells grown in the presence (0.1%, w/w) and the absence of lignin, where samples were taken at three different times during growth, beginning of exponential phase, midexponential phase and beginning of stationary phase. Lignin-amended cultures achieved twice the cell biomass as unamended cultures over three days, and in this time degraded 60% of lignin. Transcripts in early exponential phase reflected this accelerated growth. A complement of laccases, aryl-alcohol dehydrogenases, and peroxidases were most up-regulated in lignin amended conditions in mid-exponential and early stationary phases compared to unamended growth. The association of hydrogen production by way of the formate hydrogenlyase complex with lignin degradation suggests a possible value added to lignin degradation in the future.

  13. Biohydrogen and Bioethanol Production from Biodiesel-Based Glycerol by Enterobacter aerogenes in a Continuous Stir Tank Reactor

    Directory of Open Access Journals (Sweden)

    Rujira Jitrwung

    2015-05-01

    Full Text Available Crude glycerol from the biodiesel manufacturing process is being produced in increasing quantities due to the expanding number of biodiesel plants. It has been previously shown that, in batch mode, semi-anaerobic fermentation of crude glycerol by Enterobacter aerogenes can produce biohydrogen and bioethanol simultaneously. The present study demonstrated the possible scaling-up of this process from small batches performed in small bottles to a 3.6-L continuous stir tank reactor (CSTR. Fresh feed rate, liquid recycling, pH, mixing speed, glycerol concentration, and waste recycling were optimized for biohydrogen and bioethanol production. Results confirmed that E. aerogenes uses small amounts of oxygen under semi-anaerobic conditions for growth before using oxygen from decomposable salts, mainly NH4NO3, under anaerobic condition to produce hydrogen and ethanol. The optimal conditions were determined to be 500 rpm, pH 6.4, 18.5 g/L crude glycerol (15 g/L glycerol and 33% liquid recycling for a fresh feed rate of 0.44 mL/min. Using these optimized conditions, the process ran at a lower media cost than previous studies, was stable after 7 days without further inoculation and resulted in yields of 0.86 mol H2/mol glycerol and 0.75 mol ethanol/mole glycerol.

  14. Biohydrogen and Bioethanol Production from Biodiesel-Based Glycerol by Enterobacter aerogenes in a Continuous Stir Tank Reactor

    Science.gov (United States)

    Jitrwung, Rujira; Yargeau, Viviane

    2015-01-01

    Crude glycerol from the biodiesel manufacturing process is being produced in increasing quantities due to the expanding number of biodiesel plants. It has been previously shown that, in batch mode, semi-anaerobic fermentation of crude glycerol by Enterobacter aerogenes can produce biohydrogen and bioethanol simultaneously. The present study demonstrated the possible scaling-up of this process from small batches performed in small bottles to a 3.6-L continuous stir tank reactor (CSTR). Fresh feed rate, liquid recycling, pH, mixing speed, glycerol concentration, and waste recycling were optimized for biohydrogen and bioethanol production. Results confirmed that E. aerogenes uses small amounts of oxygen under semi-anaerobic conditions for growth before using oxygen from decomposable salts, mainly NH4NO3, under anaerobic condition to produce hydrogen and ethanol. The optimal conditions were determined to be 500 rpm, pH 6.4, 18.5 g/L crude glycerol (15 g/L glycerol) and 33% liquid recycling for a fresh feed rate of 0.44 mL/min. Using these optimized conditions, the process ran at a lower media cost than previous studies, was stable after 7 days without further inoculation and resulted in yields of 0.86 mol H2/mol glycerol and 0.75 mol ethanol/mole glycerol. PMID:25970750

  15. Bioremoval of lead using Pennisetum purpureum augmented with Enterobacter cloacae-VITPASJ1: A pot culture approach.

    Science.gov (United States)

    Das, Anamika; Belgaonkar, Priyanka; Raman, Aditya S; Banu, Sofia; Osborne, Jabez W

    2017-06-01

    Lead is a toxic heavy metal discharged into the ecosystem from various industries. Biological remediation strategies have been effective in the bioremoval of lead. In our current study, a phytobacterial system using Pennisetum purpureum along with lead-resistant bacterium (LRB) was employed for the uptake of lead. The LRB was obtained from lead-contaminated sites. The isolate VITPASJ1 was found to be highly tolerant to lead and was identified as an effective plant growth-promoting bacterium. The 16S rRNA sequencing revealed VITPASJ1 to be the closest neighbour of Enterobacter cloacae. The lead-resistant gene pbrA in the plant and the bacterium were amplified using a specific primer. The uptake of lead was studied by phytoremediation and rhizoremediation set-ups where the soil was supplemented with various concentrations of lead (50, 100, 150 mg/kg). The plants were uprooted at regular intervals, and the translocation of lead into the plant was determined by atomic absorption spectroscopy. The root length, shoot height and chlorophyll content were found to be higher in the rhizoremediation set-up when compared to the phytoremediation set-up. The scanning electron microscopic micrographs gave a clear picture of increased tissue damage in the root and shoot of the phytoremediation set-up as compared to the rhizoremediation set-up with LRB.

  16. Fluoroquinolone Resistance Mechanisms and population structure of Enterobacter cloacae non-susceptible to Ertapenem in North-Eastern France.

    Directory of Open Access Journals (Sweden)

    Thomas eGuillard

    2015-10-01

    Full Text Available Fluoroquinolone (FQ agents are a potential resort to treat infection due to Enterobacteriaceae producing extended spectrum β-lactamase and susceptible to FQ. In a context of increase of non-susceptibility to carbapenems among Enterobacteriaceae, we characterized FQ resistance mechanisms in 75 Enterobacter cloacae isolates non-susceptible to ertapenem in North-Eastern France in 2012 and describe the population structure by pulsed field gel electrophoresis (PFGE and multilocus sequence typing (MLST.Among them, 14.7% (12/75 carried a carbapenemase-encoding gene. Except one isolate producing VIM-1, the carbapenemase-producing isolates carried the well-known IncL/M pOXA48a plasmid. Most of the isolates (59/75 harbored at least a FQ-R determinant. qnr genes were predominant (40%, 30/75. The MLST study revealed that E. cloacae isolates’ clonality was wide (24 different STs. The more widespread STs were ST74, ST101, ST110, ST114 and ST133. Carbapenem MICs were higher for E. cloacae ST74 than for other E. cloacae isolates. PMQR determinants were more often observed in E. cloacae ST74 isolates. These findings showed that (i pOXA-48a is spreading in North-Eastern France, (ii qnr is preponderant in E. cloacae, (iii E. cloacae comprised a large amount of lineages spreading in North-Eastern France and (iv FQ as an alternative to β-lactams to treat ertapenem non-susceptible Enterobacteriaceae are compromised.

  17. Multidrug efflux systems in Escherichia coli and Enterobacter cloacae obtained from wholesome broiler carcasses Sistemas de efluxo multidroga em Escherichia coli e Enterobacter cloacae obtidas de carcaças de frangos sadios

    Directory of Open Access Journals (Sweden)

    Maria Aparecida S. Moreira

    2009-06-01

    Full Text Available Members of the Enterobacteriaceae family are present in the intestines of man and animals as commensals or are important disease causing agents. Bacteria bearing multidrug efflux systems (MDR are able to survive adverse ecological niches. Multiresistant Escherichia coli and Enterobacter cloacae isolates from wholesome broiler carcasses were investigated for the presence of MDR. Lowering of Minimal Inhibitory Concentration for antimicrobials in the presence of a proton-motive force (PMF uncoupler was tested as a potential display of the MDR phenotype. PCR amplification of the genes encoding AcrA and AcrB, components of a MDR system was performed. Diversity of each species was ascertained by Pulsed-Field Gel Electrophoresis (PFGE of DNA digested with endonuclease XbaI. For all the isolates, except E. coli 1 and E. cloacae 9, lowering of MIC or of the growth rate in the presence of antimicrobials was observed, indicating a PMF dependent resistance mechanism. Expected products of DNA amplification with acrAB derived primers was obtained with all E. coli strains and with two of the five E. cloacae strains. Dendrogram generated shows diverse pulsetypes, confirming the genetic diversity among the strains. An important issue and related public health is the fact that different models and mechanisms of antimicrobial resistance are present in a small number of non-pathogenic strains and isolated from the same origin. These may be sources of resistance genes to others microorganisms, among them, pathogenic strains.Os membros da família Enterobacteriaceae estão presentes no intestino do homem e dos animais como comensais ou agentes causadores de doença importantes. Bactérias multirresistentes podem possuir sistemas de efluxo multidrogas (MDR sendo capazes de sobreviver em nichos ecológicos adversos. Escherichia coli e Enterobacter cloacae, multirresistentes, isoladas de frangos sadios foram investigadas quanto à presença de MDR. A diminuição da

  18. Seroprevalencia de Leptospira sp., Rickettsia sp. Ehrlichia sp. en trabajadores rurales del departamento de Sucre, Colombia Seroprevalence of Leptospira sp., Rickettsia sp. and Ehrlichia sp. in rural workers of Sucre, Colombia

    Directory of Open Access Journals (Sweden)

    Rodrigo Ríos

    2008-06-01

    Full Text Available Objective. Determinar la seroprevalencia de Leptospira sp., Rickettsia sp. y Ehrlichia sp. en trabajadores de áreas rurales del departamento de Sucre. Material y métodos. Se realizó un estudio escriptivo, prospectivo, de corte transversal, que pretendió determinar la seroprevalencia e Leptospira sp., Rickettsia sp. y Ehrlichia sp. en 90 trabajadores de áreas rurales del departamento de Sucre. Se estableció la presencia de anticuerpos séricos anti-IgM específicos anti-Leptospira por la técnica de ELISA indirecta. Para la determinación de Rickettsia sp. y Ehrlichia sp. se uso la técnica de inmunofluorescencia indirecta. Resultados. La población evaluada estaba compuesta por 27 (30% ordeñadores, 21 (23% jornaleros, 18 (20% profesionales del campo y 24 (27% que realizaban otras actividades. Ventidós (24% muestras resultaron positivas en alguna de las pruebas. De éstas, 12 (13,3% fueron positivas para Leptospira sp., 7 (7,8% para Rickettsia sp. y 3 (3,3% ara Ehrlichia sp. Conclusión. Este fue el primer estudio que se llevó a cabo en el departamento de Sucre y permitió demostrar que existe una prevalencia importante de Leptospira p.,Rickettsia sp. y Ehrlichia sp.. Los factores de riesgo ocupacional fueron factores determinantes en la seropositividad.Objective. To determine the seroprevalence of Leptospira sp., Rickettsia sp. and Ehrlichia sp. in agricultural workers of Sucre. Methods. A descriptive prospective cross-sectional study was conducted in ninety rural workers of Sucre. Presence of serum antibodies anti-IgM specific anti-Leptospira by indirect ELISA was established. For the determination of Rickettsia and Ehrlichia indirect inmunoflorescence was used. Results.The population was composed by 27 (30% milkers, 21 (23% day workers, 18 farm professionals (20% and 24 (26% workers in others activities. A total of 22 (24% samples were positive to some test. Twelve (13.3% were positive to Leptospira sp., seven (7.8% to Rickettsia sp

  19. SP-100 reactor cell activation

    International Nuclear Information System (INIS)

    Wilcox, A.D.

    1991-09-01

    There are plans to test the SP-100 space reactor for 2 yr in the test facility shown in Figure 1. The vacuum vessel will be in the reactor experiment (RX) cell surrounded by an inert gas atmosphere. It is proposed that the reactor test cell could contain removable-water- shielding tanks to reduce the residual activation dose rates in the test cell after the tests are completed. This reduction will allow the facility to be considered for other uses after the SP-100 tests are completed. The radiation dose rates in the test cell were calculated for several configurations of water-shielding tanks to help evaluate this concept

  20. Caracterización fenotípica y genotípica de la resistencia enzimática a las cefalosporinas de tercera generación en Enterobacter spp. Phenotypic and genotypic characterization of resistance to third-generation cephalosporins in Enterobacter spp.

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    E. Bertona

    2005-12-01

    Full Text Available Enterobacter spp. es un patógeno intrahospitalario que presenta múltiples mecanismos de resistencia a los antibióticos b-lactámicos. Se caracterizaron fenotípica y genotípicamente las diferentes b-lactamasas presentes en 27 aislamientos consecutivos e ininterrumpidos de Enterobacter spp. (25 Enterobacter cloacae y 2 Enterobacter aerogenes. También se evaluó la habilidad de diferentes métodos fenotípicos para detectar b-lactamasas de espectro extendido (BLEE en estos microorganismos. En 15/27 aislamientos (63% se observó resistencia a las cefalosporinas de tercera generación. En 12 de los aislamientos resistentes se detectó un alto nivel de producción de cefalosporinasa cromosómica, siendo 6 de ellos también productores de PER-2. Dicha resistencia en los 3 aislamientos restantes se debió exclusivamente a la presencia de BLEE, PER-2 en 2 de ellos y CTX-M-2 en un caso. Sólo CTX-M-2 se detectó con todas las cefalosporinas probadas en los ensayos de sinergia, utilizando el método de difusión, mientras que cefepima mejoró la detección de PER-2 en 7/8 aislamientos productores de esta BLEE, 4/8 utilizando la prueba de doble disco y 7/8 comparando discos de cefepima con y sin el agregado de ácido clavulánico. El método de dilución empleado solo detectó 1/9 BLEE al comparar las cefalosporinas con y sin el agregado de inhibidor.Enterobacter spp. are becoming increasingly frequent nosocomial pathogens with multiple resistance mechanism to b-lactam antibiotics. We carried out the phenotypic and genotypic characterization of beta-lactamases in 27 Enterobacter spp. (25 Enterobacter cloacae y 2 Enterobacter aerogenes, as well as the ability of different extended spectrum b-lactamase (ESBL screening methods. Resistance to third generation cephalosporins was observed in 15/27 (63% isolates. Twelve resistant isolates produced high level chromosomal encoded AmpC b-lactamase; 6 of them were also producers of PER-2. Resistance to third

  1. Bacillus subtilis and Enterobacter cloacae endophytes from healthy Theobroma cacao L. trees can systemically colonize seedlings and promote growth.

    Science.gov (United States)

    Leite, Hianna Almeida Câmara; Silva, Anderson Barbosa; Gomes, Fábio Pinto; Gramacho, Karina Peres; Faria, José Cláudio; de Souza, Jorge Teodoro; Loguercio, Leandro Lopes

    2013-03-01

    Clonal genotypes resistant to fungal diseases are an important component of the cocoa production system in southeastern Bahia state (Brazil), so that technologies for faster production of stronger and healthier plantlets are highly desirable. In this study, the effects of inoculated bacterial endophytes isolated from healthy adult cacao plants on seedlings, and aspects related to inoculation methods, colonization patterns, and photosynthesis were investigated. Sequencing of 16S rRNA, hsp-60, and rpo-B genes placed the wild-type isolates within the species Enterobacter cloacae (isolates 341 and 344) and Bacillus subtilis (isolate 629). Spontaneous rifampicin-resistant (rif(R)) variants for 344 were also produced and tested. Endophytic application was either by immersion of surface sterilized seeds in bacterial suspensions or direct inoculation into soil, 20 days after planting non-inoculated seeds into pots. Results from in vitro recovery of inoculated isolates showed that the wild-type endophytes and rif(R) variants systemically colonized the entire cacao seedlings in 15-20 days, regardless of the inoculation method. Some endophytic treatments showed significant increases in seedlings' height, number of leaves, and dry matter. Inoculation methods affected the combined application of endophytes, which maintained the growth-promotion effects, but not in the same manner as in single applications. Interestingly, the 344-3.2 rif(R) variant showed improved performance in relation to both the wild type and another related variant. Photosynthetic rates and stomatal conductance increased significantly for some endophytic treatments, being partially associated with effects on growth and affected by the inoculation method. The results suggest that E. cloacae and B. subtilis endophytes from healthy adult plants (not transmitted by seeds) were able to promote vegetative growth on cacao seedlings. The development of products for large-scale use in seedlings

  2. Multi-time series RNA-seq analysis of Enterobacter lignolyticus SCF1 during growth in lignin-amended medium.

    Science.gov (United States)

    Orellana, Roberto; Chaput, Gina; Markillie, Lye Meng; Mitchell, Hugh; Gaffrey, Matt; Orr, Galya; DeAngelis, Kristen M

    2017-01-01

    The production of lignocellulosic-derived biofuels is a highly promising source of alternative energy, but it has been constrained by the lack of a microbial platform capable to efficiently degrade this recalcitrant material and cope with by-products that can be toxic to cells. Species that naturally grow in environments where carbon is mainly available as lignin are promising for finding new ways of removing the lignin that protects cellulose for improved conversion of lignin to fuel precursors. Enterobacter lignolyticus SCF1 is a facultative anaerobic Gammaproteobacteria isolated from tropical rain forest soil collected in El Yunque forest, Puerto Rico under anoxic growth conditions with lignin as sole carbon source. Whole transcriptome analysis of SCF1 during E.lignolyticus SCF1 lignin degradation was conducted on cells grown in the presence (0.1%, w/w) and the absence of lignin, where samples were taken at three different times during growth, beginning of exponential phase, mid-exponential phase and beginning of stationary phase. Lignin-amended cultures achieved twice the cell biomass as unamended cultures over three days, and in this time degraded 60% of lignin. Transcripts in early exponential phase reflected this accelerated growth. A complement of laccases, aryl-alcohol dehydrogenases, and peroxidases were most up-regulated in lignin amended conditions in mid-exponential and early stationary phases compared to unamended growth. The association of hydrogen production by way of the formate hydrogenlyase complex with lignin degradation suggests a possible value added to lignin degradation in the future.

  3. Characterization of Exoelectrogenic Bacteria Enterobacter Strains Isolated from a Microbial Fuel Cell Exposed to Copper Shock Load

    Science.gov (United States)

    Feng, Cuijie; Li, Jiangwei; Qin, Dan; Chen, Lixiang; Zhao, Feng; Chen, Shaohua; Hu, Hongbo; Yu, Chang-Ping

    2014-01-01

    Microorganisms capable of generating electricity in microbial fuel cells (MFCs) have gained increasing interest. Here fourteen exoelectrogenic bacterial strains were isolated from the anodic biofilm in an MFC before and after copper (Cu) shock load by Hungate roll-tube technique with solid ferric (III) oxide as an electron acceptor and acetate as an electron donor. Phylogenetic analysis of the 16S rRNA gene sequences revealed that they were all closely related to Enterobacter ludwigii DSM 16688T within the Enterobacteriaceae family, although these isolated bacteria showed slightly different morphology before and after Cu shock load. Two representative strains R2B1 (before Cu shock load) and B4B2 (after Cu shock load) were chosen for further analysis. B4B2 is resistant to 200 mg L−1 of Cu(II) while R2B1 is not, which indicated the potential selection of the Cu shock load. Raman analysis revealed that both R2B1 and B4B2 contained c-type cytochromes. Cyclic voltammetry measurements revealed that strain R2B1 had the capacity to transfer electrons to electrodes. The experimental results demonstrated that strain R2B1 was capable of utilizing a wide range of substrates, including Luria-Bertani (LB) broth, cellulose, acetate, citrate, glucose, sucrose, glycerol and lactose to generate electricity, with the highest current density of 440 mA·m−2 generated from LB-fed MFC. Further experiments indicated that the bacterial cell density had potential correlation with the current density. PMID:25412475

  4. In Vivo Evolution of Bacterial Resistance in Two Cases of Enterobacter aerogenes Infections during Treatment with Imipenem.

    Science.gov (United States)

    Philippe, Nadège; Maigre, Laure; Santini, Sébastien; Pinet, Elizabeth; Claverie, Jean-Michel; Davin-Régli, Anne-Véronique; Pagès, Jean-Marie; Masi, Muriel

    2015-01-01

    Infections caused by multidrug resistant (MDR) bacteria are a major concern worldwide. Changes in membrane permeability, including decreased influx and/or increased efflux of antibiotics, are known as key contributors of bacterial MDR. Therefore, it is of critical importance to understand molecular mechanisms that link membrane permeability to MDR in order to design new antimicrobial strategies. In this work, we describe genotype-phenotype correlations in Enterobacter aerogenes, a clinically problematic and antibiotic resistant bacterium. To do this, series of clinical isolates have been periodically collected from two patients during chemotherapy with imipenem. The isolates exhibited different levels of resistance towards multiple classes of antibiotics, consistently with the presence or the absence of porins and efflux pumps. Transport assays were used to characterize membrane permeability defects. Simultaneous genome-wide analysis allowed the identification of putative mutations responsible for MDR. The genome of the imipenem-susceptible isolate G7 was sequenced to closure and used as a reference for comparative genomics. This approach uncovered several loci that were specifically mutated in MDR isolates and whose products are known to control membrane permeability. These were omp35 and omp36, encoding the two major porins; rob, encoding a global AraC-type transcriptional activator; cpxA, phoQ and pmrB, encoding sensor kinases of the CpxRA, PhoPQ and PmrAB two-component regulatory systems, respectively. This report provides a comprehensive analysis of membrane alterations relative to mutational steps in the evolution of MDR of a recognized nosocomial pathogen.

  5. Biological characterization of lead-enhanced exopolysaccharide produced by a lead resistant Enterobacter cloacae strain P2B.

    Science.gov (United States)

    Naik, Milind Mohan; Pandey, Anju; Dubey, Santosh Kumar

    2012-09-01

    A lead resistant bacterial strain isolated from effluent of lead battery manufacturing company of Goa, India has been identified as Enterobacter cloacae strain P2B based on morphological, biochemical characters, FAME profile and 16S rDNA sequence data. This bacterial strain could resist lead nitrate up to 1.6 mM. Significant increase in exopolysaccharide (EPS) production was observed as the production increased from 28 to 108 mg/L dry weight when exposed to 1.6 mM lead nitrate in Tris buffered minimal medium. Fourier-transformed infrared spectroscopy of this EPS revealed presence of several functional groups involved in metal binding viz. carboxyl, hydroxyl and amide groups along with glucuronic acid. Gas chromatography coupled with mass spectrometry analysis of alditol-acetate derivatives of acid hydrolysed EPS produced in presence of 1.6 mM lead nitrate demonstrated presence of several neutral sugars such as rhamnose, arabinose, xylose, mannose, galactose and glucose, which contribute to lead binding hydroxyl groups. Scanning electron microscope coupled with energy dispersive X-ray spectrometric analysis of this lead resistant strain exposed to 1.6 mM lead nitrate interestingly revealed mucous EPS surrounding bacterial cells which sequestered 17 % lead (as weight %) extracellularly and protected the bacterial cells from toxic effects of lead. This lead resistant strain also showed multidrug resistance. Thus these results significantly contribute to better understanding of structure, function and environmental application of lead-enhanced EPSs produced by bacteria. This lead-enhanced biopolymer can play a very important role in bioremediation of several heavy metals including lead.

  6. Characterization of exoelectrogenic bacteria enterobacter strains isolated from a microbial fuel cell exposed to copper shock load.

    Directory of Open Access Journals (Sweden)

    Cuijie Feng

    Full Text Available Microorganisms capable of generating electricity in microbial fuel cells (MFCs have gained increasing interest. Here fourteen exoelectrogenic bacterial strains were isolated from the anodic biofilm in an MFC before and after copper (Cu shock load by Hungate roll-tube technique with solid ferric (III oxide as an electron acceptor and acetate as an electron donor. Phylogenetic analysis of the 16S rRNA gene sequences revealed that they were all closely related to Enterobacter ludwigii DSM 16688T within the Enterobacteriaceae family, although these isolated bacteria showed slightly different morphology before and after Cu shock load. Two representative strains R2B1 (before Cu shock load and B4B2 (after Cu shock load were chosen for further analysis. B4B2 is resistant to 200 mg L-1 of Cu(II while R2B1 is not, which indicated the potential selection of the Cu shock load. Raman analysis revealed that both R2B1 and B4B2 contained c-type cytochromes. Cyclic voltammetry measurements revealed that strain R2B1 had the capacity to transfer electrons to electrodes. The experimental results demonstrated that strain R2B1 was capable of utilizing a wide range of substrates, including Luria-Bertani (LB broth, cellulose, acetate, citrate, glucose, sucrose, glycerol and lactose to generate electricity, with the highest current density of 440 mA·m-2 generated from LB-fed MFC. Further experiments indicated that the bacterial cell density had potential correlation with the current density.

  7. Occurrence of Blastocystis sp. in water catchments at Malay villages and Aboriginal settlement during wet and dry seasons in Peninsular Malaysia

    Directory of Open Access Journals (Sweden)

    Samseh Abdullah Noradilah

    2016-10-01

    Full Text Available In the tropics, there are too few studies on isolation of Blastocystis sp. subtypes from water sources; in addition, there is also an absence of reported studies on the occurrence of Blastocystis sp. subtypes in water during different seasons. Therefore, this study was aimed to determine the occurrence of Blastocystis sp. subtypes in river water and other water sources that drained aboriginal vicinity of highly endemic intestinal parasitic infections during wet and dry seasons. Water samples were collected from six sampling points of Sungai Krau (K1–K6 and a point at Sungai Lompat (K7 and other water sources around the aboriginal villages. The water samples were collected during both seasons, wet and dry seasons. Filtration of the water samples were carried out using a flatbed membrane filtration system. The extracted DNA from concentrated water sediment was subjected to single round polymerase chain reaction and positive PCR products were subjected to sequencing. All samples were also subjected to filtration and cultured on membrane lactose glucuronide agar for the detection of faecal coliforms. During wet season, Blastocystis sp. ST1, ST2 and ST3 were detected in river water samples. Blastocystis sp. ST3 occurrence was sustained in the river water samples during dry season. However Blastocystis sp. ST1 and ST2 were absent during dry season. Water samples collected from various water sources showed contaminations of Blastocystis sp. ST1, ST2, ST3 and ST4, during wet season and Blastocystis sp. ST1, ST3, ST8 and ST10 during dry season. Water collected from all river sampling points during both seasons showed growth of Escherichia coli and Enterobacter aerogenes, indicating faecal contamination. In this study, Blastocystis sp. ST3 is suggested as the most robust and resistant subtype able to survive in any adverse environmental condition. Restriction and control of human and animal faecal contaminations to the river and other water sources

  8. Identificação de enterobactérias em macacos-prego-galego (Sapajus flavius mantidos em cativeiro no estado da Paraíba

    Directory of Open Access Journals (Sweden)

    Ayodhya Cardoso Ramalho

    2015-05-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2015v28n3p177 O objetivo deste estudo foi isolar e identificar enterobactérias presentes em duas populações de macaco-prego-galego (Sapajus flavius mantidas em cativeiro. O estudo foi realizado com 12 animais, seis do Centro de Triagem de Animais Silvestres (CETAS, em Cabedelo-PB, e seis do Zoológico de João Pessoa. A coleta das amostras de fezes foi realizada diretamente na ampola retal com o auxílio de swabs estéreis e processadas para o isolamento das bactérias em meios seletivos, seguida da identificação por provas bioquímicas. As frequências observadas nas amostras do CETAS foram de: 80% (4/5 para Salmonella spp.; 20% (1/5 para Shigella spp.; e 20% (1/5 para Enterobacter spp. Já no zoológico, a frequência observada foi de 100% (3/3 para Salmonella spp. Devido ao fato de que essas enterobactérias são possíveis causadoras de infeções, há necessidade de melhorar o monitoramento da saúde desses animais, com investigações periódicas em unidades do CETAS e em zoológicos. Simultaneamente, constata-se a necessidade de monitorar a saúde dos profissionais que lidam diretamente com esses animais, por meio de exames periódicos, bem como a adoção de medidas de biossegurança adequadas para evitar a transmissão desses patógenos.

  9. Epidemiology and molecular characterization of extended-spectrum beta-lactamase-producing Enterobacter spp., Pantoea agglomerans, and Serratia marcescens isolates from a Bulgarian hospital.

    Science.gov (United States)

    Markovska, Rumyana Donkova; Stoeva, Temenuga Jekova; Bojkova, Kalina Dineva; Mitov, Ivan Gergov

    2014-04-01

    Forty-two extended-spectrum beta-lactamase (ESBL)-producing isolates of Enterobacter aerogenes, Enterobacter cloacae, Pantoea agglomerans, and Serratia marcescens, collected consecutively during the period January-November 2011 from the University Hospital in Varna, Bulgaria, were studied to characterize their ESBLs by isoelectric focusing, group-specific PCR, and sequencing. The epidemiological relationship was evaluated by random amplified polymorphic DNA analysis (RAPD). Transferability of ESBL genes was determined by conjugation experiments. Plasmid analysis was done by replicon typing and PstI fingerprinting. The overall rate of ESBL production was 20%. The most widespread enzyme was CTX-M-3, found in 64%. It was dominant in E. aerogenes (100%) and S. marcescens (83%). SHV-12, CTX-M-3, and CTX-M-15 were found among E. cloacae isolates in 50%, 35%, and 45%, respectively. Three main CTX-M-3-producing epidemic clones of E. aerogenes and S. marcescens have been detected. Among E. cloacae isolates, six different RAPD profiles were discerned. The plasmids harboring blaCTX-M-3 belonged to IncL/M type and demonstrated similar PstI fingerprinting profiles. IncFII plasmids were detected in two CTX-M-15-producing E. cloacae isolates. Our results demonstrate wide intrahospital dissemination of clonal E. aerogenes and S. marcescens isolates, carrying IncL/M conjugative plasmids.

  10. Stimulating effects of two plant growth-promoting bacteria, Enterobacter ludwigii Ez-185-17 and Raoultella terrigena Ez-555-6, on flax culture

    Science.gov (United States)

    Sarron, Elodie; Clément, Nathalie; Pawlicki-Jullian, Nathalie; Gaillard, Isabelle; Boitel-Conti, Michèle

    2018-04-01

    Two bacteria, Enterobacter ludwigii Ez-185-17 and Raoultella terrigena Ez-555-6, isolated from root nodules of Medicago lupulina from the Chernobyl exclusion zone, were identified in a previous study and shown not to disturb plant growth. The main goal of this work is to elucidate the relationships between these bacteria and flax, in particular whether they display activities such as plant growth promoting bacteria (PGPB) properties or modulation hairy root development. In order to better understand their role in plants, some known PGPB properties were determined in comparison with several control bacteria. The influence of these bacteria on Linum usitatissimum growth under hydroponic conditions was also investigated. Our study shows that both bacteria belong to PGPB since they were able to increase considerably the root surface area of flax, especially Raoultella terrigena Ez-555-6. Significant IAA production and phosphate solubilization of Enterobacter ludwigii Ez-185-17 were highlighted, which enabled these biochemical PGPB properties to be correlated with their effects on flax growth. However, Raoultella terrigena Ez-555-6 did not express high biochemical activities, suggesting that other PGPB abilities should be studied in order to establish the link with flax growth improvement.

  11. Long-Term, Low-Frequency Cluster of a German-Imipenemase-1-Producing Enterobacter hormaechei ssp. steigerwaltii ST89 in a Tertiary Care Hospital in Germany.

    Science.gov (United States)

    Wendel, Andreas F; Meyer, Sebastian; Deenen, René; Köhrer, Karl; Kolbe-Busch, Susanne; Pfeffer, Klaus; Willmann, Matthias; Kaasch, Achim J; MacKenzie, Colin R

    2018-05-11

    Enterobacter cloacae complex is a common cause of hospital outbreaks. A retrospective and prospective molecular analysis of carbapenem-resistant clinical isolates in a tertiary care center demonstrated an outbreak of a German-imipenemase-1 (GIM-1) metallo-beta-lactamase-producing Enterobacter hormaechei ssp. steigerwaltii affecting 23 patients between 2009 and 2016. Thirty-three isolates were sequence type 89 by conventional multilocus sequence typing (MLST) and displayed a maximum difference of 49 out of 3,643 targets in the ad-hoc core-genome MLST (cgMLST) scheme (SeqSphere+ software; Ridom, Münster, Germany). The relatedness of all isolates was confirmed by further maximum-likelihood phylogeny. One clonal complex of highly related isolates (≤15 allele difference in cgMLST) contained 17 patients, but epidemiological data only suggested five transmission events. The bla GIM-1 -gene was embedded in a class-1-integron (In770) and the Tn21-subgroup transposon Tn6216 (KC511628) on a 25-kb plasmid. Environmental screening detected one colonized sink trap in a service room. The outbreak was self-limited as no further bla GIM-1 -positive E. hormaechei has been isolated since 2016. Routine molecular screening of carbapenem-nonsusceptible gram-negative isolates detected a long-term, low-frequency outbreak of a GIM-1-producing E. hormaechei ssp. steigerwaltii clone. This highlights the necessity of molecular surveillance.

  12. Survival and growth of Enterobacter sakazakii in infant cereal as affected by composition, reconstitution liquid, and storage temperature.

    Science.gov (United States)

    Lin, Li-Chun; Beuchat, Larry R

    2007-06-01

    Invasive infections caused by Enterobacter sakazakii have occurred predominantly in low-birth-weight neonates and infants younger than 2 months of age. However, infections have also occurred in healthy infants up to 8 months of age and in immunocompromised children up to 4 years of age. The ability of E. sakazakii to survive and grow in infant cereals as affected by composition of the cereal, composition of the reconstitution liquid, and temperature is unknown. A study was done to determine the survival and growth characteristics of E. sakazakii initially at populations of 0.005 and 0.52 CFU/ml of infant rice cereal, oatmeal cereal, or rice with mixed fruit cereal reconstituted with water, milk, or apple juice. Reconstituted cereals were stored at 4, 12, 21, and 30 degrees C, and populations were monitored for up to 72 h. Growth did not occur in reconstituted cereals stored at 4 degrees C or in cereals reconstituted with apple juice and stored at 12 degrees C. Populations (> or =1 CFU/ml) were detected in cereals reconstituted with water or milk and stored at 12, 21, and 30 degres C for 24, 8, and 4 h, respectively. The composition of infant cereals did not markedly affect the survival or growth of E. sakazakii in reconstituted cereals. Populations of E. sakazakii in reconstituted cereal decreased with increases in populations of mesophilic aerobic microflora up to 8 to 9 log CFU/ml, which was concurrent with decreases in pH. E. sakazakii, initially at 2.62 log CFU/ml of rice cereal reconstituted with apple juice (pH 4.32), survived at 40C for at least 14 days. The pathogen grew at 21 and 30 degrees C within 2 days and then decreased to undetectable levels (<1 CFU/10 ml) in cereal stored at 21 degrees C for 5 days or 30'C for 4 days. Initially, at 7.32 log CFU/ml, E. sakazakii was detected in rice cereal stored at 4 degrees C for 50 days. It is recommended that reconstituted infant cereals stored at 21 or 30 degrees C be discarded within 4 h after preparation or

  13. Expression of zinc transporter genes in rice as influenced by zinc-solubilizing Enterobacter cloacae strain ZSB14

    Directory of Open Access Journals (Sweden)

    Selvaraj eKrithika

    2016-04-01

    Full Text Available Zinc (Zn deficiency in major food crops has been considered as an important factor affecting the crop production and subsequently the human health. Rice (Oryza sativa is sensitive to Zn deficiency and thereby causes malnutrition to most of the rice-eating Asian populations. Application of zinc solubilizing bacteria (ZSB could be a sustainable agronomic approach to increase the soil available Zn which can mitigate the yield loss and consequently the nutritional quality of rice. Understanding the molecular interactions between rice and unexplored ZSB is useful for overcoming Zn deficiency problems. In the present study, the role of zinc solubilizing bacterial strain Enterobacter cloacae strain ZSB14 on regulation of Zn-regulated transporters and iron (Fe-regulated transporter-like protein (ZIP genes in rice under iron sufficient and deficient conditions was assessed by quantitative real-time reverse transcription PCR. The expression patterns of OsZIP1, OsZIP4 and OsZIP5 in root and shoot of rice were altered due to the Zn availability as dictated by Zn sources and ZSB inoculation. Fe sufficiency significantly reduced the root and shoot OsZIP1 expression, but not the OsZIP4 and OsZIP5 levels. Zinc oxide in the growth medium up-regulated all the assessed ZIP genes in root and shoot of rice seedlings. When ZSB was inoculated to rice seedlings grown with insoluble zinc oxide in the growth medium, the expression of root and shoot OsZIP1, OsZIP4 and OsZIP5 was reduced. In the absence of zinc oxide, ZSB inoculation up-regulated OsZIP1 and OsZIP5 expressions. Zinc nutrition provided to the rice seedling through ZSB-bound zinc oxide solubilization was comparable to the soluble zinc sulphate application which was evident through the ZIP genes’ expression and the Zn accumulation in root and shoot of rice seedlings. These results demonstrate that zinc solubilizing bacteria could play a crucial role in zinc fertilization and fortification of rice.

  14. Penicillium araracuarense sp. nov., Penicillium elleniae sp. nov., Penicillium penarojense sp. nov., Penicillium vanderhammenii sp. nov. and Penicillium wotroi sp. nov., isolated from leaf litter.

    Science.gov (United States)

    Houbraken, Jos; López-Quintero, Carlos A; Frisvad, Jens C; Boekhout, Teun; Theelen, Bart; Franco-Molano, Ana Esperanza; Samson, Robert A

    2011-06-01

    Several species of the genus Penicillium were isolated during a survey of the mycobiota of leaf litter and soil in Colombian Amazon forest. Five species, Penicillium penarojense sp. nov. (type strain CBS 113178(T) = IBT 23262(T)), Penicillium wotroi sp. nov. (type strain CBS 118171(T) = IBT 23253(T)), Penicillium araracuarense sp. nov. (type strain CBS 113149(T) = IBT 23247(T)), Penicillium elleniae sp. nov. (type strain CBS 118135(T) = IBT 23229(T)) and Penicillium vanderhammenii sp. nov. (type strain CBS 126216(T) = IBT 23203(T)) are described here as novel species. Their taxonomic novelty was determined using a polyphasic approach, combining phenotypic, molecular (ITS and partial β-tubulin sequences) and extrolite data. Phylogenetic analyses showed that each novel species formed a unique clade for both loci analysed and that they were most closely related to Penicillium simplicissimum, Penicillium janthinellum, Penicillium daleae and Penicillium brasilianum. An overview of the phylogeny of this taxonomically difficult group is presented, and 33 species are accepted. Each of the five novel species had a unique extrolite profile of known and uncharacterized metabolites and various compounds, such as penicillic acid, andrastin A, pulvilloric acid, paxillin, paspaline and janthitrem, were commonly produced by these phylogenetically related species. The novel species had a high growth rate on agar media, but could be distinguished from each other by several macro- and microscopical characteristics.

  15. Genotypic and Phenotypic Detection of AmpC β-lactamases in Enterobacter spp. Isolated from a Teaching Hospital in Malaysia.

    Science.gov (United States)

    Mohd Khari, Fatin Izzati; Karunakaran, Rina; Rosli, Roshalina; Tee Tay, Sun

    2016-01-01

    The objective of this study was to determine the occurrence of chromosomal and plasmid-mediated β-lactamases (AmpC) genes in a collection of Malaysian isolates of Enterobacter species. Several phenotypic tests for detection of AmpC production of Enterobacter spp. were evaluated and the agreements between tests were determined. Antimicrobial susceptibility profiles for 117 Enterobacter clinical isolates obtained from the Medical Microbiology Diagnostic Laboratory, University Malaya Medical Centre, Malaysia, from November 2012-February 2014 were determined in accordance to CLSI guidelines. AmpC genes were detected using a multiplex PCR assay targeting the MIR/ACT gene (closely related to chromosomal EBC family gene) and other plasmid-mediated genes, including DHA, MOX, CMY, ACC, and FOX. The AmpC β-lactamase production of the isolates was assessed using cefoxitin disk screening test, D69C AmpC detection set, cefoxitin-cloxacillin double disk synergy test (CC-DDS) and AmpC induction test. Among the Enterobacter isolates in this study, 39.3% were resistant to cefotaxime and ceftriaxone and 23.9% were resistant to ceftazidime. Ten (8.5%) of the isolates were resistant to cefepime, and one isolate was resistant to meropenem. Chromosomal EBC family gene was amplified from 36 (47.4%) E. cloacae and three (25%) E. asburiae. A novel blaDHA type plasmid-mediated AmpC gene was identified for the first time from an E. cloacae isolate. AmpC β-lactamase production was detected in 99 (89.2%) of 111 potential AmpC β-lactamase producers (positive in cefoxitin disk screening) using D69C AmpC detection set. The detection rates were lower with CC-DDS (80.2%) and AmpC induction tests (50.5%). There was low agreement between the D69C AmpC detection set and the other two phenotypic tests. Of the 40 isolates with AmpC genes detected in this study, 87.5%, 77.5% and 50.0% of these isolates were positive by the D69C AmpC detection set, CC-DDS and AmpC induction tests, respectively

  16. Neues vom Heringsparasiten Ichthyophonus sp.

    OpenAIRE

    Lang, Thomas

    1994-01-01

    Seit dem Massensterben von Heringen entlang der schwedischen Südküste im Sommer 1991, aufgrund einer Infektion mit dem parasitischen Pilz Ichthyophonus sp., wird der Gesundheitszustand der Heringsbestände in den europäischen Seegebieten intensiv überwacht. Diese Untersuchungen, an denen sich auch die Bundesforschungsanstalt für Fischerei beteiligt, werden koordiniert von der "Arbeitsgruppe über Pathologie und Krankheiten mariner Organismen" des Internationalen Rates für Meeresforschung (IC...

  17. Bacterial content in the intestine of frozen common carp Cyprinus ...

    African Journals Online (AJOL)

    Aeromonas hydrophila, Aeromonas sp., Bacillus sp., Enterobacter sp., Micrococcus sp., Photobacterium damselae, Serratia liquefaciens, Shewanella putrefaciens, Staphylococcus sp., Streptococcus sp. and Vibrio sp. survived after prolonged freezing. Two bacterial species viz. Shewanella putrefaciens and Aeromonas ...

  18. Complete Sequence of pSAM7, an IncX4 Plasmid Carrying a Novel blaCTX-M-14b Transposition Unit Isolated from Escherichia coli and Enterobacter cloacae from Cattle

    NARCIS (Netherlands)

    Stokes, M.O.; Abuoun, M.; Umur, S.; Wu, G.; Partridge, S.R.; Mevius, D.J.; Coldham, N.G.; Fielder, M.D.

    2013-01-01

    The same plasmid carrying blaCTX-M-14b was identified from an Escherichia coli isolate and an Enterobacter cloacae isolate collected from cattle in the United Kingdom by complete plasmid sequencing. This 35,341-bp plasmid, pSAM7, had an IncX4 backbone that is 99% identical to that of pJIE143 from a

  19. Cronobacter (Enterobacter) sakazakii

    Science.gov (United States)

    Cronobacter sakazakii has been identified as an infrequently isolated opportunistic pathogen. Over 120 cases of C. sakazakii-related illness have been reported and most reported cases are life-threatening infections. Many of these outbreaks have been linked the consumption of C. sakazakii-contamina...

  20. DISTRIBUSI Solen sp DI PERAIRAN KABUPATEN BANGKALAN

    Directory of Open Access Journals (Sweden)

    Eva Ari Wahyuni

    2016-03-01

    Full Text Available DISTRIBUTION OF Solen sp IN BANGKALAN WATERSSolen sp potential needs to be developed on the island of Madura, particularly in Bangkalan. Solen sp utilization has increased which has the potential to overfishing. Therefore, this study aims to determine the density of Solen sp and their ecology in the waters Modung village, Modung District, Bangkalan. The experiment was conducted in April 2015 using the descriptive method. The materials used include Solen sp and physico-chemical parameters of the environment (temperature, salinity, pH, and substrate. The analyzes were conducted at the Laboratory of Marine Science, Department of Marine Sciences, Trunojoyo University of Madura by using the tool grabsampler, sieveshaker, and pipetting with gravimetric method. The analysis shows the range of values of temperature between 29-300C, salinity between 31-32 ppt, pH were 7.9-8.0 and the type of substrate in the form of sandy mud, as well as the density of Solen sp from 8-10 individuals/m2. All measurement results indicate normal conditions and in accordance with the sea water quality standard for marine life, which can be a suitable habitat for the growth and development of Solen sp. This condition is thought to affect the density of Solen sp.Keywords: Bangkalan, density, distribution, Solen sp, substrate.ABSTRAKPotensi Solen sp perlu dikembangkan di pulau Madura, khususnya di Kabupaten Bangkalan. Pemanfaatan Solen sp mengalami peningkatan sehingga berpotensi overfishing. Untuk itu, penelitian ini bertujuan untuk mengetahui kepadatan Solen sp dan ekologinya di perairan desa Modung, Kecamatan Modung, Kabupaten Bangkalan. Penelitian dilaksanakan pada bulan April 2015 dengan metode deskriptif. Materi dan bahan yang digunakan diantaranya Solen sp dan parameter fisika-kimia lingkungan (suhu, salinitas, pH, dan substrat. Analisa dilakukan di Laboratorium Ilmu Kelautan, Program studi/Jurusan Ilmu Kelautan Universitas Trunojoyo Madura dengan menggunakan alat

  1. The spread of bla OXA-48 and bla OXA-244 carbapenemase genes among Klebsiella pneumoniae, Proteus mirabilis and Enterobacter spp. isolated in Moscow, Russia.

    Science.gov (United States)

    Fursova, Nadezhda K; Astashkin, Eugeny I; Knyazeva, Anastasia I; Kartsev, Nikolay N; Leonova, Ekaterina S; Ershova, Olga N; Alexandrova, Irina A; Kurdyumova, Natalia V; Sazikina, Svetlana Yu; Volozhantsev, Nikolay V; Svetoch, Edward A; Dyatlov, Ivan A

    2015-11-02

    The spread of carbapenemase-producing Enterobacteriaceae (CPE) is a great problem of healthcare worldwide. Study of the spread for bla OXA-48-like genes coding epidemically significant carbapenemases among hospital pathogens is important for the regional and global epidemiology of antimicrobial resistance. Antibacterial resistant isolates of Klebsiella pneumoniae (n = 95) from 54 patients, P. mirabilis (n = 32) from 20 patients, Enterobacter aerogenes (n = 6) from four patients, and Enterobacter cloacae (n = 4) from four patients were collected from January, 2013 to October, 2014 in neurosurgical intensive care unit (ICU) of the Burdenko Neurosurgery Institute, Moscow. Characteristics of the isolates were done using susceptibility tests, PCR detection of the resistance genes, genotyping, conjugation, DNA sequencing, and bioinformatic analysis. Major strains under study were multi drug resistant (MDR), resistant to three or more functional classes of drugs simultaneously-98.9 % K. pneumoniae, 100 % P. mirabilis, one E. aerogenes isolate, and one E. cloacae isolate. Molecular-genetic mechanism of MDR in K. pneumoniae and P. mirabilis isolates were based on carrying of epidemic extended-spectrum beta-lactamase bla CTX-M-15 gene (87.2 and 90.6 % accordingly), carbapenemase bla OXA-48-like gene (55.3 and 23.3 % accordingly), and class 1 (54.8 and 31.3 % accordingly) and class 2 (90.6 % P. mirabilis) integrons. The bla OXA-48-like-positive K. pneumoniae were collected during whole two-year surveillance period, while P. mirabilis and Enterobacter spp. carrying bla OXA-48-like genes were detected only after four and 18 months after the research start, respectively. The bla OXA-48-like gene acquisition was shown for P. mirabilis isolates collected from five patients and for E. cloacae isolate collected from one patient during their stay in the ICU, presumably from bla OXA-48-like-positive K. pneumoniae. The source of the bla OXA-244 gene acquired by E

  2. Introduction to the SP theory of intelligence

    OpenAIRE

    Wolff, J Gerard

    2018-01-01

    This article provides a brief introduction to the "Theory of Intelligence" and its realisation in the "SP Computer Model". The overall goal of the SP programme of research, in accordance with long-established principles in science, has been the simplification and integration of observations and concepts across artificial intelligence, mainstream computing, mathematics, and human learning, perception, and cognition. In broad terms, the SP system is a brain-like system that takes in "New" infor...

  3. Evaluation of antioxidant and cytotoxic properties of Cynobacteria, Limnothrix sp. and Leptolyngbya sp. from Arabian sea

    Digital Repository Service at National Institute of Oceanography (India)

    Anas, A.; Vinothkumar, S.; Gupta, S.; Jasmin, C.; Joseph, V.; Parameswaran, P.S.; Nair, S.

    The hexane fractions of the marine cyanobacteria: Leptolyngbya sp. and Limnothrix sp., collected from Arabian Sea were found to display promising antioxidant properties than their ethyl acetate fraction during radical scavenging ABTS/DPPH assays (IC...

  4. Xylanolytic enzyme systems in Arthrobacter sp MTCC 5214 and Lactobacillus sp.

    Digital Repository Service at National Institute of Oceanography (India)

    Khandeparker, R.; Jalal, T.

    The production of extracellular xylanolytic enzymes such as xylanase, alfa-L-arabinofuranosidase (alfa-l-AFase), and acetyl xylan esterase (Axe) by marine Arthrobacter sp and Lactobacillus sp was investigated using different carbon sources Induction...

  5. Large IncHI2-plasmids encode extended-spectrum β-lactamases (ESBLs) in Enterobacter spp. bloodstream isolates, and support ESBL-transfer to Escherichia coli.

    Science.gov (United States)

    Nilsen, E; Haldorsen, B C; Sundsfjord, A; Simonsen, G S; Ingebretsen, A; Naseer, U; Samuelsen, O

    2013-11-01

    We investigated the prevalence of extended-spectrum β-lactamases (ESBLs) in Enterobacter spp. bloodstream isolates from 19 hospital laboratories in Norway during 2011. A total of 62/230 (27%) isolates were resistant to third-generation cephalosporins and four (1.7%) were ESBL-positive; blaCTX -M-15 (n = 3) and blaSHV -12 (n = 1). This is comparable to the prevalence of ESBLs in clinical isolates of Escherichia coli and Klebsiella pneumoniae in Norway during the same period. All ESBL-positive isolates were multidrug resistant (MDR) and harboured plasmid-mediated quinolone resistance. Three isolates supported transfer of large IncHI2-plasmids harbouring ESBL- and MDR-encoding genes to E. coli recipients by in vitro conjugation. © 2013 The Authors Clinical Microbiology and Infection © 2013 European Society of Clinical Microbiology and Infectious Diseases.

  6. Pengendalian Hayati Penyakit Layu Fusarium Pisang (Fusarium Oxysporum F.sp. Cubense) dengan Trichoderma SP.

    OpenAIRE

    Sudirman, Albertus; Sumardiyono, Christanti; Widyastuti, Siti Muslimah

    2011-01-01

    The aim of this research was to study the inhibiting ability of Trichoderma sp. to control fusarium wilt of banana in greenhouse condition. The experiments consisted of the antagonism test between Trichoderma sp. and Fusarium oxysporum f.sp. cubense (Foc) in vitro using dual culture method and glass house experiment which was arranged in 3×3 Factorial Complete Randomized Design. First factor of the latter experiment was the dose of Trichoderma sp. culture (0, 25, and 50 g per polybag), second...

  7. Selective C(sp2)-C(sp) bond cleavage: the nitrogenation of alkynes to amides.

    Science.gov (United States)

    Qin, Chong; Feng, Peng; Ou, Yang; Shen, Tao; Wang, Teng; Jiao, Ning

    2013-07-22

    Breakthrough: A novel catalyzed direct highly selective C(sp2)-C(sp) bond functionalization of alkynes to amides has been developed. Nitrogenation is achieved by the highly selective C(sp2)-C(sp) bond cleavage of aryl-substituted alkynes. The oxidant-free and mild conditions and wide substrate scope make this method very practical. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. First report of Anisakis sp. in Epinephelus sp. in East Indonesia

    OpenAIRE

    Annytha Ina Rohi Detha; Diana Agustiani Wuri; Julianty Almet; Yuni Riwu; Christin Melky

    2018-01-01

    Objective: The present research was conducted to identify the prevalence of Anisakis sp. as fish-borne zoonoses in Epinephelus sp. in territorial waters of East Nusa Tenggara, Indonesia. Materials and methods: A total of 50 fish (Epinephelus sp.) were collected from Kupang Fish Market in East Nusa Tenggara. Identification of Anisakis sp. was performed based on morphological observations considering shape of ventriculus, boring tooth, and mucron using binocular microscope. Results: Prev...

  9. Identification of Ideal Multi-targeting Bioactive Compounds Against Mur Ligases of Enterobacter aerogenes and Its Binding Mechanism in Comparison with Chemical Inhibitors.

    Science.gov (United States)

    Chakkyarath, Vijina; Natarajan, Jeyakumar

    2017-10-31

    Enterobacter aerogenes have been reported as important opportunistic and multi-resistant bacterial pathogens for humans during the last three decades in hospital wards. The emergence of drug-resistant E. aerogenes demands the need for developing new drugs. Peptidoglycan is an important component of the cell wall of bacteria and the peptidoglycan biochemical pathway is considered as the best source of antibacterial targets. Within this pathway, four Mur ligases MurC, MurD, MurE, and MurF are responsible for the successive additions of L-alanine and suitable targets for developing novel antibacterial drugs. As an inference from this fact, we modeled the three-dimensional structure of above Mur ligases using best template structures available in PDB and analyzed its common binding features. Structural refinement and energy minimization of the predicted Mur ligases models is also being done using molecular dynamics studies. The models of Mur ligases were further investigated for in silico docking studies using bioactive plant compounds from the literature. Interestingly, these results indicate that four plant compounds Isojuripidine, Atroviolacegenin, Porrigenin B, and Nummularogenin showing better docking results in terms of binding energy and number of hydrogen bonds. All these four compounds are spirostan-based compounds with differences in side chains and the amino acid such as ASN, LYS, THR, HIS, ARG (polar) and PHE, GLY, VAL, ALA, MET (non-polar) playing active role in binding site of all four Mur ligases. Overall, in the predicted model, the four plant compounds with its binding features could pave way to design novel multi-targeted antibacterial plant-based bioactive compounds specific to Mur ligases for the treatment of Enterobacter infections.

  10. Pseudoxanthomonas koreensis sp. nov. and Pseudoxanthomonas daejeonensis sp. nov.

    Science.gov (United States)

    Yang, Deok-Chun; Im, Wan-Taek; Kim, Myung Kyum; Lee, Sung-Taik

    2005-03-01

    Gram-negative, non-spore-forming, rod-shaped bacteria, T7-09(T) and TR6-08(T), were isolated from soil from a ginseng field in South Korea and characterized to determine their taxonomic position. 16S rRNA gene sequence analysis showed that the two isolates shared 99.5 % sequence similarity. Strains T7-09(T) and TR6-08(T) were shown to belong to the Proteobacteria and showed the highest levels of sequence similarity to Pseudoxanthomonas broegbernensis DSM 12573(T) (98.1 %), Pseudoxanthomonas mexicana AMX 26B(T) (97.4-97.5 %), Pseudoxanthomonas japonensis 12-3(T) (96.5-96.6 %), Pseudoxanthomonas taiwanensis ATCC BAA-404(T) (95.7 %) and Xanthomonas campestris ATCC 33913(T) (96.3-96.5 %). The sequence similarity values with respect to any species with validly published names in related genera were less than 96.5 %. The detection of a quinone system with Q-8 as the predominant compound and a fatty acid profile with C(15 : 0) iso as the predominant acid supported the assignment of the novel isolates to the order 'Xanthomonadales'. The two isolates could be distinguished from the established species of the genus Pseudoxanthomonas by the presence of quantitative unsaturated fatty acid C(17 : 1) iso omega9c and by their unique biochemical profiles. The results of DNA-DNA hybridization clearly demonstrated that T7-09(T) and TR6-08(T) represent separate species. On the basis of these data, it is proposed that T7-09(T) (=KCTC 12208(T)=IAM 15116(T)) and TR6-08(T) (=KCTC 12207(T)=IAM 15115(T)) be classified as the type strains of two novel Pseudoxanthomonas species, for which the names Pseudoxanthomonas koreensis sp. nov. and Pseudoxanthomonas daejeonensis sp. nov., respectively, are proposed.

  11. Specialised predation by Palpimanus sp. (Araneae: Palpimanidae ...

    African Journals Online (AJOL)

    This is the first detailed report on the natural prey and the prey-capture tactics of a Palpimanus sp. from Entebbe (Uganda). Although this species fed occasionally on insects, its dominant prey in the field was other spiders, especially jumping spiders (Salticidae) and their eggs. Encounters between Palpimanus sp. and ...

  12. Kultivasi Scenedesmus SP. Pada Medium Air Limbah

    OpenAIRE

    Kawaroe, Mujizat

    2011-01-01

    Proses fotosintesis pada mikroalga membutuhkan CO2 dan cahaya matahari serta nutrien untuk pertumbuhannya. Kultivasi Scenedesmus sp. pada medium air limbah bertujuan guna mencukupi kebutuhan mikroalga akan nutrien dan mengurangi masukan dari bahan kimia yang terkandung dalam air limbah tersebut ke lingkungan. Kultivasi Scenedesmus sp. dilakukan selama tujuh hari pada medium air limbah industri tanpa penambahan nutri...

  13. Uso do açafrão (Curcuma longa L. na redução da Escherichia coli (ATCC 25922 e Enterobacter aerogenes (ATCC 13048 em ricota The use of turmeric in the reduction of Escherichia coli (ATCC 25922 and Enterobacter aerogenes (ATCC 13048 in ricotta

    Directory of Open Access Journals (Sweden)

    Sandra Ribeiro Maia

    2004-04-01

    Full Text Available Considerando o envolvimento de queijos como veículo de microrganismos patogênicos, foi avaliada a eficiência do extrato alcoólico de cúrcuma adicionado à ricota, na redução de Escherichia coli e Enterobacter aerogenes. Foram fabricados três lotes de ricota cremosa e inoculados com 104 UFC/mL de Escherichia coli (ATCC 25922 e 105 UFC/mL de Enterobacter aerogenes (ATCC 13048. Às ricotas, foram adicionados 0,4% de NaCl e extrato alcoólico de Curcuma longa L., em concentrações que variaram de 0,0% a 2,0%. As ricotas foram avaliadas físico-química e microbiologicamente em 0, 1, 7, 14 e 21 dias de armazenamento refrigerado. O percentual de umidade das ricotas foi, em média, de 73%. O pH médio observado foi de 5,4 e o percentual de gordura de 3%. Pelos resultados, evidenciou-se, após 21 dias, uma redução do número de Escherichia coli de aproximadamente dois ciclos logaritmicos nos tratamentos utilizados de 0,5%, 1,0%, 1,5% e 2,0% de cúrcuma. Já para Enterobacter aerogenes, a redução foi menor, de aproximadamente um ciclo logaritmico, de 105 UFC/mL para 104 UFC/mL, também nos tratamentos utilizados de 0,5%, 1,0%, 1,5% e 2,0% de cúrcuma. Apesar de os resultados evidenciarem uma redução do número de células viáveis dos microrganismos avaliados, a cúrcuma não deverá ser o único meio preservativo, considerando uma contaminação inicial de 104 UFC/mL de Escherichia coli e 105 UFC/mL de Enterobacter aerogenes, pois não atenderia à legislação vigente quanto aos requisitos microbiológicos para queijos.Considering the cheese involvement as a vehicle of pathogenic microorganisms it was evaluated the eficciency of the ethanolic turmeric extract added to ricotta, in the reduction of Escherichia coli and Enterobacter aerogenes. Three lots of creamy ricotta were manufacturated and inoculated with 104 UFC/mL of Escherichia coli (ATCC 25922 and 105 UFC/mL of Enterobacter aerogenes (ATCC 13048. It was added 0,4% of NaCl and

  14. Guide til gode spørgeskemaer

    DEFF Research Database (Denmark)

    Olsen, Henning

    Spørgeskemaundersøgelser bliver ofte brugt til at dokumentere forskellige forhold og begrunde politiske beslutninger. Men resultaterne kan være forbundet med stor usikkerhed. Det kræver omhu og stor sproglig formåen at udarbejde spørgeskemaer. Seniorforsker Henning Olsen har i flere år arbejdet med...... viden om, hvordan folk forstår sproglige meddelelser og genkalder sig informationer. I guiden behandles emner som fx styrende problemstillinger og spørgsmåls fokus og neutralitet, formulering af åbne eller lukkede spørgsmål og svarkategorier, tematiske spørgeforløb, aflastning af svarpersoners...

  15. Glyphosate catabolism by Pseudomonas sp

    International Nuclear Information System (INIS)

    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- 14 C] glyphosate revealed that approximately 50-59% of the C3 carbon was oxidized to CO 2 . Fractionation of stationary phase cells labeled with [3- 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- 14 C]glyphosate revealed that [3- 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

  16. 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.).

    Science.gov (United States)

    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.

  17. Trichoderma sp. dalam Pengendalian Penyakit Layu Fusarium pada Tanaman Tomat

    OpenAIRE

    Novita, Trias

    2013-01-01

    Penelitian ini bertujuan untuk mengetahui peran Trichoderma sp dalam pengendalianpenyakit layu fusarium pada tanaman tomat. Penelitian dilaksanakan di Rumah Kaca FakultasPertanian Universitas Jambi, perlakuannya terdiri dari : t0 = tanpa Trichoderma sp; t1 = 25 gTrichoderma sp/8 kg media; t2 = 50 g Trichoderma sp/8 kg media; t3 = 75 g Trichoderma sp/8 kgmedia; dan t4 = 100 g Trichoderma sp /8 kg media. Hasil penelitian menunjukkan bahwa Trichodermasp berperan dalam mengendalikan penyakit layu...

  18. INTERAKSI ANTARA Trichoderma Harzianum, Penicillium SP. DAN Pseudomonas SP. SERTA KAPASITAS ANTAGONISMENYA TERHADAP Phytophthora CapsicilN VITRO*[Interaction Among Trichoderma Harzianum, Penicillium SP., Pseudomonas SP. and Antagonism Capacities Against Phy

    OpenAIRE

    Suharna, Nandang

    2003-01-01

    A preliminary study has been done to know antagonism capacities of three isolates of Trichoderma harzianum, two isolates of Penicillium sp.and one isolate of Pseudomonas sp.against Phytophthora capsici in vitro and interaction among those six antagonists.The highest antagonism capacity possessed by Penicillium sp. KN1, respectively followed by Penicillium sp.KN2,Pseudomonas sp. GH1 and the three T. harzianum isolates. Except for those three T. harzianum isolates, the two Penicillium sp.isolat...

  19. SP140L, an Evolutionarily Recent Member of the SP100 Family, Is an Autoantigen in Primary Biliary Cirrhosis

    Directory of Open Access Journals (Sweden)

    Mario Saare

    2015-01-01

    Full Text Available The SP100 family members comprise a set of closely related genes on chromosome 2q37.1. The widely expressed SP100 and the leukocyte-specific proteins SP110 and SP140 have been associated with transcriptional regulation and various human diseases. Here, we have characterized the SP100 family member SP140L. The genome sequence analysis showed the formation of SP140L gene through rearrangements of the two neighboring genes, SP100 and SP140, during the evolution of higher primates. The SP140L expression is interferon-inducible with high transcript levels in B cells and other peripheral blood mononuclear cells. Subcellularly, SP140L colocalizes with SP100 and SP140 in nuclear structures that are devoid of SP110, PML, or p300 proteins. Similarly to SP100 and SP140 protein, we detected serum autoantibodies to SP140L in patients with primary biliary cirrhosis using luciferase immunoprecipitation system and immunoblotting assays. In conclusion, our results show that SP140L is phylogenetically recent member of SP100 proteins and acts as an autoantigen in primary biliary cirrhosis patients.

  20. Fresh Water Cyanobacteria Geitlerinema sp. CCC728 and Arthrospira sp. CCC729 as an Anticancer Drug Resource

    OpenAIRE

    Srivastava, Akanksha; Tiwari, Ratnakar; Srivastava, Vikas; Singh, Tej Bali; Asthana, Ravi Kumar

    2015-01-01

    An increasing number of cancer patients worldwide, especially in third world countries, have raised concern to explore natural drug resources, such as the less explored fresh water filamentous cyanobacteria. Six strains of cyanobacteria (Phormidium sp. CCC727, Geitlerinema sp. CCC728, Arthrospira sp. CCC729, Phormidium sp. CCC731, Phormidium sp. CCC730, and Leptolyngbya sp. CCC732) were isolated (paddy fields and ponds in the Banaras Hindu University, campus) and five strains screened for ant...

  1. Antibacterial Actions and Potential Phototoxic Effects of Volatile oils of Foeniculum sp. (fennel, Salvia sp. (sage, Vitis sp. (grape, Lavandula sp. (lavender

    Directory of Open Access Journals (Sweden)

    Elif Ayse Erdogan Eliuz

    2016-09-01

    Full Text Available In the present study, the volatile compounds of essential oil of Foeniculum vulgare (fennel, Salvia officinalis (sage, Vitis vinifera (grape, Lavandula angustifolia (lavender were analysed by gas chromatography-mass spectrometry (GC-MS using the Nist and Willey libraries. It was determined that the main components of Foeniculum sp. were anethole (41.11%, carvacrol (9.18%. whereas main components of Salvia sp were 1.8 cineole (34.09%, caryophyllene (10.95%, camphor (9.44%, α-pinene (8.42%. Vitis sp. contained linoleic acid (36.98%, 2,4-decadienal (30.79%. Finally, volatile component of Lavandula sp. was linalool (33.57%, linalyl acetate (30.74%. Photoxic antibacterial activity of volatile oil of those plants against Escherichia coli (ATCC 25293, Klebsiella pneumoniae (10031, Salmonella thyphimurium, Bacillus subtilis (ATCC 6633, Staphylococcus aureus (ATCC 25925, Enterococcus feacalis (ATCC 29212 were examined by using disc diffusion method. We demonstrated that volatile oil effectively can be activated by a standard LED light. In vitro, significant phototoxicity was demonstrated by volatile oil of Foeniculum sp. and Vitis sp. (P < 0.05, while minor phototoxicity was induced by Lavandula sp. Therefore, volatile oil of plant can be considered as a potential photosensitizer in the photochemical therapy.

  2. TurboSP and the Topological Trigger

    CERN Document Server

    Belavin, Vladislav

    2016-01-01

    TurboSP was originally proposed as an alternative to Full stream in LHCb data flow. TurboSP is a data flow strategy which not only selects events that should be preserved, like in Full stream, but also provides selective persistence. This is achieved by saving candidates and subset of the reconstruction. During this summer project we investigated the physics viability of using TurboSP with the topological lines and found out a possibility to reduce the number of kept tracks per event by two times while keeping a ratio of fully picked up interesting decay modes on $\\sim 97 \\%$ level.

  3. Caracterización molecular de aislamientos de enterobacter cloacae multirresistentes, productores ß-Lactamasas provenientes de pacientes de un hospital de tercer nivel de Bogotá

    Directory of Open Access Journals (Sweden)

    Ibonne Aydee García Romero

    2005-07-01

    Full Text Available Antecedentes. Las enterobacterias, antaño flora normal del tracto gastrointestinal, han cambiado su biología y emergido como agentes patógenos nosocomiales que se tornan resistentes los antibióticos conocidos. Objetivo. Realizar la caracterización epidemiológico-molecular de 20 aislamientos de Enterobacter cloacae resistentes a cefalosporinas de tercera generación; provenientes de un hospital de tercer nivel de Bogotá-Colombia. Material y métodos. Los aislamientos fueron identificados mediante sistemas automatizados Microscan y VITEK, se utilizó el Enterobacter asbureae como control externo inter-especie. La confirmación de resistencia se hizo por técnica de difusión en agar, y una vez establecida se realizó BLEE para comprobación. La determinación de puntos isoeléctricos se hizo, mediante lisis por ultrasonido y la genotipificación mediante la metodología para bacterias Gramnegativas propuesta por Versalovic. Resultados: Los aislamientos colectados durante un año fueron causantes de 15 casos de infección Intrahospitalaria y dos colonizaciones. Todos los aislamientos presentaron resistencia a cefotaxima, ceftazidima, ceftriaxona, aztreonam y ciprofloxacina, 95% a amikacina, gentamicina y cloranfenicol, 75% a trimetoprim/sulfametoxazol, 20% a cefepime y todos fueron sensibles a imipenem. Dos aislamientos fueron confirmados como productores de â-lactamasas de espectro extendido (BLEE por la técnica microbiológica de disco combinado. Por isoelectroenfoque presentaron dos â-lactamasas con puntos isoeléctricos (pI de 5,4 y 8,2. En los 18 aislamientos no inhibidos por ácido clavulánico, se detectaron entre 2 y 4 â-lactamasas con pI de 5,4; 6,0; 7,0; 8,2 y mayor que 8,2; la resistencia a cefalosporinas de tercera generación podría ser atribuida a la hiperproducción de AmpC; los valores de pI sugieren la producción simultánea de â-lactamasas tipo SHV y TEM. La genotipificación mediante tres metodologías de rep

  4. Pengendalian Hayati Penyakit Layu Fusarium Pisang (Fusarium oxysporum f.sp. cubense dengan Trichoderma sp.

    Directory of Open Access Journals (Sweden)

    Albertus Sudirman

    2011-07-01

    Full Text Available The aim of this research was to study the inhibiting ability of Trichoderma sp. to control fusarium wilt of banana in greenhouse condition. The experiments consisted of the antagonism test between Trichoderma sp. and Fusarium oxysporum f.sp. cubense (Foc in vitro using dual culture method and glass house experiment which was arranged in 3×3 Factorial Complete Randomized Design. First factor of the latter experiment was the dose of Trichoderma sp. culture (0, 25, and 50 g per polybag, second factor was time of Trichoderma culture application (2 weeks before Foc inoculation, at same time with Foc inoculation and 2 weeks after Foc inoculation. Trichoderma sp. was cultured in mixed rice brand and chaff medium. The disease intensity was observed with scoring system of wilting leaves (0–4. The results showed that Trichoderma sp. was antagonistic against Foc in vitro and inhibited 86% of Foc colony development. Mechanism of antagonism between Trichoderma sp. and Foc was hyperparasitism. Trichoderma hyphae coiled around Foc hyphae. Lysis of Foc hyphae was occurred at the attached site of Trichoderma hyphae on Foc hyphae. Added banana seedling with Trichoderma sp. Culture reduced disease intensity of Fusarium wilt. Suggested dose of Trichoderma culture application in glass house was 25 g/polybag, given at the same time with Foc inoculation. Penelitian ini bertujuan untuk mengetahui kemampuan Trichoderma sp. untuk pengendalian penyakit layu fusarium pisang di rumah kaca. Penelitian meliputi pengujian daya hambat Fusarium oxysporum f.sp. cubense (Foc in vitro dan kemampuan menekan intensitas penyakit di rumah kaca. Penelitian in vitro meliputi uji antagonisme dan mekanismenya yang dilakukan secara dual culture. Uji pengaruh Trichoderma sp. terhadap penyakit layu Fusarium dilakukan di rumah kaca dengan Rancangan Acak Lengkap Faktorial. Faktor pertama adalah dosis biakan Trichoderma sp., dengan tiga aras (0, 25, 50 g/per bibit dalam polibag. Faktor kedua

  5. Association between the Presence of Aminoglycoside-Modifying Enzymes and In Vitro Activity of Gentamicin, Tobramycin, Amikacin, and Plazomicin against Klebsiella pneumoniae Carbapenemase- and Extended-Spectrum-β-Lactamase-Producing Enterobacter Species.

    Science.gov (United States)

    Haidar, Ghady; Alkroud, Ammar; Cheng, Shaoji; Churilla, Travis M; Churilla, Bryce M; Shields, Ryan K; Doi, Yohei; Clancy, Cornelius J; Nguyen, M Hong

    2016-09-01

    We compared the in vitro activities of gentamicin (GEN), tobramycin (TOB), amikacin (AMK), and plazomicin (PLZ) against 13 Enterobacter isolates possessing both Klebsiella pneumoniae carbapenemase and extended-spectrum β-lactamase (KPC+/ESBL+) with activity against 8 KPC+/ESBL-, 6 KPC-/ESBL+, and 38 KPC-/ESBL- isolates. The rates of resistance to GEN and TOB were higher for KPC+/ESBL+ (100% for both) than for KPC+/ESBL- (25% and 38%, respectively), KPC-/ESBL+ (50% and 17%, respectively), and KPC-/ESBL- (0% and 3%, respectively) isolates. KPC+/ESBL+ isolates were more likely than others to possess an aminoglycoside-modifying enzyme (AME) (100% versus 38%, 67%, and 5%; P = 0.007, 0.06, and 1 AME than with ≤1 AME. The presence of at least 2/3 of KPC, SHV, and TEM predicted the presence of AMEs. PLZ MICs against all isolates were ≤4 μg/ml, regardless of KPC/ESBL pattern or the presence of AMEs. In conclusion, GEN and TOB are limited as treatment options against KPC+ and ESBL+ Enterobacter PLZ may represent a valuable addition to the antimicrobial armamentarium. A full understanding of AMEs and other aminoglycoside resistance mechanisms will allow clinicians to incorporate PLZ rationally into treatment regimens. The development of molecular assays that accurately and rapidly predict antimicrobial responses among KPC- and ESBL-producing Enterobacter spp. should be a top research priority. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  6. Detection of Salmonella sp., Vibrio sp. and total plate count bacteria on blood cockle (Anadara granosa)

    Science.gov (United States)

    Ekawati, ER; Yusmiati, S. N. H.

    2018-01-01

    Blood cockle (Anadara granosa) has high level of zinc and protein, which is beneficial for therapeutic function for malnourished particularly stunting case in children. Zinc in animal foods is more absorbable than that from vegetable food. Blood cockle (Anadara granosa) is rich in nutrient and an excellent environment for the growth of microorganisms. This research aimed to identify the contamination of Salmonella sp., Vibrio sp. and total plate count bacteria on blood cockle (Anadara granosa). This was observation research with laboratory analysis. Salmonella sp. and Vibrio sp. were detected from blood cockle. Total plate count was determine of the total amount of the bacteria. Results detected from 20 samples of blood cockle showed that all samples were negative of Salmonella sp. and 1 sample positive Vibrio sp. The result of total plate count bacteria was < 5 x 105 colony/g sample.

  7. Superhard sp2–sp3 hybrid carbon allotropes with tunable electronic properties

    Directory of Open Access Journals (Sweden)

    Meng Hu

    2016-05-01

    Full Text Available Four sp2–sp3 hybrid carbon allotropes are proposed on the basis of first principles calculations. These four carbon allotropes are energetically more favorable than graphite under suitable pressure conditions. They can be assembled from graphite through intralayer wrinkling and interlayer buckling, which is similar to the formation of diamond from graphite. For one of the sp2–sp3 hybrid carbon allotropes, mC24, the electron diffraction patterns match these of i-carbon, which is synthesized from shock-compressed graphite (H. Hirai and K. Kondo, Science, 1991, 253, 772. The allotropes exhibit tunable electronic characteristics from metallic to semiconductive with band gaps comparable to those of silicon allotropes. They are all superhard materials with Vickers hardness values comparable to that of cubic BN. The sp2–sp3 hybrid carbon allotroes are promising materials for photovoltaic electronic devices, and abrasive and grinding tools.

  8. EOP Gold Coral (Gerardia sp.) Growth Measurements

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gold coral (Gerardia sp.) trees that were inspected years earlier on Pisces submersible dives were revisited and their change in size measured. The fishery for...

  9. Metabolites from marine fungus Aspergillus sp.

    Digital Repository Service at National Institute of Oceanography (India)

    Wahidullah, S.; Rajmanickam, R.; DeSouza, L.

    Chemical examination of a methanolic extract of the marine fungus, Aspergillus sp., isolated from marine grass environment, yielded a steroid, ergosterol peroxide (1), and a mixture of known glyceride esters (2,3) of unsaturated fatty acids...

  10. SP (4,R) symmetry in light nuclei

    International Nuclear Information System (INIS)

    Peterson, D.R.

    1979-01-01

    A classification of nuclear states according to the noncompact sympletic Lie algebras sp(2n,R), n = 1, 2, 3, is investigated. Such a classification has recently been shown to be physically meaningful. This classification scheme is the appropriate generalization fo Elliott's SU 3 model of rotational states in deformed light nuclei to include core excitations. A restricted classification according to the Lie algebra, sp(4,R), is motivated. Truncation of the model space to a single sp(4,R) irreducible representation allows the inclusion of states possessing very high excitation energy. An sp(4,R) model study is performed on S = T = 0 positive-parity rotational bands in the deformed light nuclei 16 O and 24 Mg. States are included in the model space that possess up to 10h ω in excitation energy. Results for the B(E2) transition rates compare favorable with experiment, without resort to effective charges

  11. Progress in SP-100 tribological coatings

    International Nuclear Information System (INIS)

    Ring, P.J.; Roy, P.; Schuster, G.B.; Busboom, H.J.

    1992-01-01

    The SP-100 reactor will operate at temperatures up to 1500K in high vacuum. To address the SP-100 needs, a tribology development program has been established at GE to investigate candidate coating materials. Materials were selected based on their high thermodynamic stability, high melting point, compatibility with the substrate, and coefficients of thermal expansion similar to niobium-1% zirconium-the candidate structural material for SP-100. An additional requirement was that the deposition processes should be commercially available to coat large components. This paper presents the details regarding the SP-100 Tribology Development Program including background information, specific bearing requirements, basis for coating material selection, testing methods and the initial results covering the early years of this program

  12. Silencing the SpMPK1, SpMPK2, and SpMPK3 Genes in Tomato Reduces Abscisic Acid—Mediated Drought Tolerance

    Directory of Open Access Journals (Sweden)

    Yan Liang

    2013-11-01

    Full Text Available Drought is a major threat to agriculture production worldwide. Mitogen-activated protein kinases (MAPKs play a pivotal role in sensing and converting stress signals into appropriate responses so that plants can adapt and survive. To examine the function of MAPKs in the drought tolerance of tomato plants, we silenced the SpMPK1, SpMPK2, and SpMPK3 genes in wild-type plants using the virus-induced gene silencing (VIGS method. The results indicate that silencing the individual genes or co-silencing SpMPK1, SpMPK2, and SpMPK3 reduced the drought tolerance of tomato plants by varying degrees. Co-silencing SpMPK1 and SpMPK2 impaired abscisic acid (ABA-induced and hydrogen peroxide (H2O2-induced stomatal closure and enhanced ABA-induced H2O2 production. Similar results were observed when silencing SpMPK3 alone, but not when SpMPK1 and SpMPK2 were individually silenced. These data suggest that the functions of SpMPK1 and SpMPK2 are redundant, and they overlap with that of SpMPK3 in drought stress signaling pathways. In addition, we found that SpMPK3 may regulate H2O2 levels by mediating the expression of CAT1. Hence, SpMPK1, SpMPK2, and SpMPK3 may play crucial roles in enhancing tomato plants’ drought tolerance by influencing stomatal activity and H2O2 production via the ABA-H2O2 pathway.

  13. Cellulose powder from Cladophora sp. algae.

    Science.gov (United States)

    Ek, R; Gustafsson, C; Nutt, A; Iversen, T; Nyström, C

    1998-01-01

    The surface are and crystallinity was measured on a cellulose powder made from Cladophora sp. algae. The algae cellulose powder was found to have a very high surface area (63.4 m2/g, N2 gas adsorption) and build up of cellulose with a high crystallinity (approximately 100%, solid state NMR). The high surface area was confirmed by calculations from atomic force microscope imaging of microfibrils from Cladophora sp. algae.

  14. Production and assay of cellulolytic enzyme activity of Enterobacter cloacae WPL 214 isolated from bovine rumen fluid waste of Surabaya abbatoir, Indonesia

    Directory of Open Access Journals (Sweden)

    W. P. Lokapirnasari

    2015-03-01

    Full Text Available Aim: This study aims to produce and assay cellulolytic enzyme activity (endo-(1,4-β-D-glucanase, exo-(1,4-β-Dglucanase, and β-glucosidase, at optimum temperature and optimum pH of Enterobacter cloacae WPL 214 isolated from bovine rumen fluid waste of Surabaya Abbatoir, Indonesia. Materials and Methods: To produce enzyme from a single colony of E. cloacae WPL 214, 98 × 1010 CFU/ml of isolates was put into 20 ml of liquid medium and incubated in a shaker incubator for 16 h at 35°C in accordance with growth time and optimum temperature of E. cloacae WPL 214. Further on, culture was centrifuged at 6000 rpm at 4°C for 15 min. Pellet was discarded while supernatant containing cellulose enzyme activity was withdrawn to assay endo-(1,4-β-D-glucanase, exo-(1,4-β-D-glucanase, and β-glucosidase. Results: Cellulase enzyme of E. cloacae WPL 214 isolates had endoglucanase activity of 0.09 U/ml, exoglucanase of 0.13 U/ml, and cellobiase of 0.10 U/ml at optimum temperature 35°C and optimum pH 5. Conclusion: E. cloacae WPL 214 isolated from bovine rumen fluid waste produced cellulose enzyme with activity as cellulolytic enzyme of endo-(1,4-β-D-glucanase, exo-(1,4-β-D-glucanase and β-glucosidase.

  15. Fermentative hydrogen production by two novel strains of Enterobacter aerogenes HGN-2 and HT 34 isolated from sea buried crude oil pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Jayasinghearachchi, H.S.; Sarma, Priyangshu M.; Singh, Sneha; Mandal, Ajay K.; Lal, Banwari [Environmental and Industrial Biotechnology Division, The Energy and Resource Institute, Darbari Seth Block, Habitat Place, Lodhi Road, New Delhi 110 003 (India); Aginihotri, Anil [Corporate HSF, Oil and Natural Gas Corporation, New Delhi (India)

    2009-09-15

    Present study investigated fermentative hydrogen production of two novel isolates of Enterobacter aerogenes HGN-2 and HT 34 isolated from oil water mixtures. The two isolates were identified as novel strains of E. aerogenes based on 16S rRNA gene. The batch fermentations of two strains from glucose and xylose were carried out using economical culture medium under various conditions such as temperature, initial pH, NaCl, Ni{sup +}/Fe{sup ++}, substrate concentrations for enhanced fermentation process. Both the strains favoured wide range of pH (6.5-8.0) at 37 C for optimum production (2.20-2.23 mol H{sub 2}/mol-glucose), which occurred through acetate/butyrate pathway. At 55 C, both strains favoured 6.0-6.5 and acetate type fermentation was predominant in HT 34. Hydrogen production by HT 34 from xylose was highly pH dependant and optimum production was at pH 6.5 (circa 1.98 mol-H{sub 2}/mol-xylose) through acetate pathway. The efficiency of the strain HGN-2 at pH 6.5 was 1.92-1.94 mol-H{sub 2}/mol-xylose, and displayed both acetate and butyrate pathways. At 55 C, very low hydrogen production was detected (less than 0.5 m mol/mol-xylose). (author)

  16. Impact of furan derivatives and phenolic compounds on hydrogen production from organic fraction of municipal solid waste using co-culture of Enterobacter aerogenes and E. coli.

    Science.gov (United States)

    Sharma, Preeti; Melkania, Uma

    2017-09-01

    In the present study, the effect of furan derivatives (furfural and 5-hydroxymethylfurfural) and phenolic compounds (vanillin and syringaldehyde) on hydrogen production from organic fraction of municipal solid waste (OFMSW) was investigated using co-culture of facultative anaerobes Enterobacter aerogenes and E. coli. The inhibitors were applied in the concentration ranges of 0.25, 0.5, 1, 2 and 5g/L each. Inhibition coefficients of phenolic compounds were higher than those of furan derivatives and vanillin exhibited maximum inhibition coefficients correspondingly lowest hydrogen yield among all inhibitors. Furfural and 5-hydroxymethylfurfural addition resulted in an average decrease of 26.99% and 37.16% in hydrogen yield respectively, while vanillin and syringaldehyde resulted in 49.40% and 42.26% average decrease in hydrogen yield respectively. Further analysis revealed that Furfural and 5-hydroxymethylfurfural were completely degraded up to concentrations of 1g/L, while vanillin and syringaldehyde were degraded completely up to the concentration of 0.5g/L. Volatile fatty acid generation decreased with inhibitors addition. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Molecular cloning, characterization, and overexpression of a novel [Fe]-hydrogenase isolated from a high rate of hydrogen producing Enterobacter cloacae IIT-BT 08

    International Nuclear Information System (INIS)

    Mishra, Jayshree; Khurana, Seema; Kumar, Narendra; Ghosh, Ananta K.; Das, Debabrata

    2004-01-01

    Degenerate primers were designed from the conserved zone of hydA structural gene encoding for catalytic subunit of [Fe]-hydrogenase of different hydrogen producing bacteria. A 750 bp of PCR product was amplified by using the above-mentioned degenerate primers and genomic DNA of Enterobacter cloacae IIT-BT 08 as template. The amplified PCR product was cloned and sequenced. The sequence showed the presence of an ORF of 450 bp with significant similarity (40%) with C-terminal end of the conserved zone (H-cluster) of [Fe]- hydrogenase. hydA ORF was then amplified and cloned in-frame with GST in pGEX4T-1 and overexpressed in a non-hydrogen producing Escherichia coli BL-21 to produce a GST-fusion protein of a calculated molecular mass of about 42.1 kDa. Recombinant protein was purified and specifically recognized by anti-GST monoclonal antibody through Western blot. Southern hybridization confirmed the presence of this gene in E. cloacae IIT-BT 08 genome. In vitro hydrogenase assay with the overexpressed hydrogenase enzyme showed that it is catalytically active upon anaerobic adaptation. In vivo hydrogenase assay confirmed the presence of H 2 gas in the gas mixture obtained from the batch culture of recombinant E. coli BL-21. A tentative molecular mechanism has been proposed about the transfer of electron from electron donor to H-cluster without the mediation of the F-cluster

  18. Lactobacillus bulgaricus Prevents Intestinal Epithelial Cell Injury Caused by Enterobacter sakazakii-Induced Nitric Oxide both In Vitro and in the Newborn Rat Model of Necrotizing Enterocolitis▿

    Science.gov (United States)

    Hunter, Catherine J.; Williams, Monica; Petrosyan, Mikael; Guner, Yigit; Mittal, Rahul; Mock, Dennis; Upperman, Jeffrey S.; Ford, Henri R.; Prasadarao, Nemani V.

    2009-01-01

    Enterobacter sakazakii is an emerging pathogen that has been associated with outbreaks of necrotizing enterocolitis (NEC) as well as infant sepsis and meningitis. Our previous studies demonstrated that E. sakazakii induces NEC in a newborn rat model by inducing enterocyte apoptosis. However, the mechanisms responsible for enterocyte apoptosis are not known. Here we demonstrate that E. sakazakii induces significant production of nitric oxide (NO) in rat intestinal epithelial cells (IEC-6) upon infection. The elevated production of NO, which is due to increased expression of inducible NO synthase, is responsible for apoptosis of IEC-6 cells. Notably, pretreatment of IEC-6 cells with Lactobacillus bulgaricus (ATCC 12278) attenuated the upregulation of NO production and thereby protected the cells from E. sakazakii-induced apoptosis. Furthermore, pretreatment with L. bulgaricus promoted the integrity of enterocytes both in vitro and in the infant rat model of NEC, even after challenge with E. sakazakii. Infection of IEC-6 cells with E. sakazakii upregulated several genes related to apoptosis, cytokine production, and various signaling pathways, as demonstrated by rat gene array analysis, and this upregulation was subdued by pretreatment with L. bulgaricus. In agreement with these data, L. bulgaricus pretreatment protected newborn rats infected with E. sakazakii from developing NEC, resulting in improved survival. PMID:19075027

  19. Biosurfactant-enhanced hydrogen production from organic fraction of municipal solid waste using co-culture of E. coli and Enterobacter aerogenes.

    Science.gov (United States)

    Sharma, Preeti; Melkania, Uma

    2017-11-01

    The effect of biosurfactants (surfactin and saponin) on the hydrogen production from organic fraction of municipal solid waste (OFMSW) was investigated using co-culture of facultative anaerobes Enterobacter aerogenes and E. coli. The biosurfactants were applied in the concentration ranges of 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5 and 5.0% each. Cumulative hydrogen production (P), maximum hydrogen production rate (Rmax) and lag phases (λ) were analyzed using modified Gompertz model. Results revealed that both the biosurfactants were effective in hydrogen production enhancement. The maximum cumulative hydrogen production of 743.5±14.4ml and 675.6±12.1ml and volumetric hydrogen production of 2.12L H2 /L substrate and 1.93L H2 /L substrate was recorded at 3.5% surfactin and 3.0% saponin respectively. Corresponding highest hydrogen yields were 79.2mlH 2 /gCarbo initial and 72.0mlH 2 /gCarbo initial respectively. Lag phase decreased from 12.5±2.0h at control to a minimum of 9.0±2.8h and 9.5±2.1h at 3.5% surfactin and 3.0% saponin respectively. Volatile fatty acid generation was increased with biosurfactants addition. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. A biological method for in-situ synthesis of hydroxyapatite-coated magnetite nanoparticles using Enterobacter aerogenes: Characterization and acute toxicity assessments.

    Science.gov (United States)

    Ahmadzadeh, Elham; Talebnia Rowshan, Farid; Hosseini, Morteza

    2017-04-01

    Hydroxyapatite (HA)-coated magnetite nanoparticles (MNPs) are being widely investigated for various applications in medical engineering and wastewater treatment. In this work, the MNPs were thoroughly coated by bacterial synthesized HA nanoparticles during biomineralization process using Enterobacter aerogenes. The resulting bacterial-induced precipitate was then calcined at 600°C and investigated with respect to structural characteristics, particle size and magnetic strength by XRD, FT-IR, SEM, EDS, TEM and VSM analyses. The effects of MNPs and HA-coated MNPs (HA-MNPs) on the viability of human MCF-7 cell lines were also investigated via mitochondrial activity test (MTT) and lactate dehydrogenase (LDH) assays. The powder characterization results showed appropriate structural properties for HA-MNPs samples. The particles diameter size of the MNPs and HA-MNPs were in the range of 3-25nm and 20-80nm, respectively. The biologically-synthesized HA-MNPs formed a stable suspension in water while keeping their magnetic property. The saturation magnetization (Ms) of HA-MNPs was measured at ~10emug -1 which was in good agreement with the structural composition of this sample. Finally, the results of the cell lines viability indicated that coating of toxic MNPs via biomineralization was a promising approach in order to synthesize bio-compatible magnetic nanoparticles with suitable physical and chemical structural characteristics. The toxicity level of MNPs was reduced by 10 fold when coated by bacterial-synthesized HA. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Impact of heavy metals on hydrogen production from organic fraction of municipal solid waste using co-culture of Enterobacter aerogenes and E. Coli.

    Science.gov (United States)

    Sharma, Preeti; Melkania, Uma

    2018-05-01

    In the present study, the effect of heavy metals (lead, mercury, copper, and chromium) on the hydrogen production from the organic fraction of municipal solid waste (OFMSW) was investigated using co-culture of facultative anaerobes Enterobacter aerogenes and E. coli. Heavy metals were applied at concentration range of 0.5, 1, 2, 5, 10, 20, 50 and 100 mg/L. The results revealed that lead, mercury, and chromium negatively affected hydrogen production for the range of concentrations applied. Application of copper slightly enhanced hydrogen production at low concentration and resulted in the hydrogen yield of 36.0 mLH 2 /gCarbo initial with 10 mg/L copper supplementation as compared to 24.2 mLH 2 /gCarbo initial in control. However, the higher concentration of copper (>10 mg/L) declined hydrogen production. Hydrogen production inhibition potential of heavy metals can be arranged in the following increasing order: Cu 2+  metal addition. Thus, the present study reveals that the presence of heavy metals in the feedstock is detrimental for the hydrogen production. Therefore, it is essential to remove the toxic heavy metals prior to anaerobic digestion. Copyright © 2018 Elsevier Ltd. All rights reserved.

  2. Isolation of Enterobacter aerogenes carrying blaTEM-1 and blaKPC-3 genes recovered from a hospital Intensive Care Unit.

    Science.gov (United States)

    Pulcrano, Giovanna; Pignanelli, Salvatore; Vollaro, Adriana; Esposito, Matilde; Iula, Vita Dora; Roscetto, Emanuela; Soriano, Amata Amy; Catania, Maria Rosaria

    2016-06-01

    Enterobacter aerogenes has recently emerged as an important hospital pathogen. In this study, we showed the emergence of E. aerogenes isolates carrying the blaKPC gene in patients colonized by carbapenem-resistant Klebsiella pneumoniae strains. Two multiresistant E. aerogenes isolates were recovered from bronchial aspirates of two patients hospitalized in the Intensive Care Unit at the "Santa Maria della Scaletta" Hospital, Imola. The antimicrobial susceptibility test showed the high resistance to carbapenems and double-disk synergy test confirmed the phenotype of KPC and AmpC production. Other investigation revealed that ESBL and blaKPC genes were carried on the conjugative pKpQIL plasmid. This is a relevant report in Italy that describes a nosocomial infection due to the production of KPC beta-lactamases by an E. aerogenes isolate in patients previously colonized by K. pneumoniae carbapenem-resistant. In conclusion, it's necessary a continuous monitoring of multidrug-resistant strains for the detection of any KPC-producing bacteria that could expand the circulation of carbapenem-resistant pathogens. © 2016 APMIS. Published by John Wiley & Sons Ltd.

  3. Microencapsulation of a putative probiotic Enterobacter species, C6-6, to protect rainbow trout, Oncorhynchus mykiss (Walbaum), against bacterial coldwater disease.

    Science.gov (United States)

    Ghosh, B; Cain, K D; Nowak, B F; Bridle, A R

    2016-01-01

    Flavobacterium psychrophilum is the causative agent of bacterial coldwater disease (BCWD), which has a major impact on salmonid aquaculture globally. An Enterobacter species, C6-6, isolated from the gut of rainbow trout, Oncorhynchus mykiss (Walbaum), has been identified as a potential probiotic species providing protection against BCWD. This study examined the effects of alginate microencapsulation on the protective efficacy of C6-6 against BCWD in vivo when administered to rainbow trout fry orally or by intraperitoneal (IP) injection. Viable C6-6 bacteria were microencapsulated successfully, and this process (microencapsulation) did not significantly deteriorate its protective properties as compared to the administration of non-microencapsulated C6-6 bacteria. Both oral and IP delivery of C6-6 achieved significantly better protection than control treatments that did not contain C6-6 bacteria. The highest relative percent survival (RPS) resulted from IP delivery (71.4%) and was significantly greater than the highest oral RPS (38.6%). Successful intestinal colonization was not critical to protective effects of C6-6. The study showed that C6-6 administration, with or without encapsulation, was a viable choice for protecting fry from BCWD especially when administered intraperitoneally. © 2014 John Wiley & Sons Ltd.

  4. Penggunaan Jamur Antagonis Trichoderma SP. Dan Gliocladium SP. Untuk Mengendalikan Penyakit Layu Fusarium Pada Tanaman Bawang Merah (Allium Ascalonicum L.)

    OpenAIRE

    Arie Ramadhina, Arie Ramadhina; Lisnawita, Lisnawita; Lubis, Lahmuddin

    2013-01-01

    The use of antagonism fungus of Trichoderma sp. and Gliocladium sp. for controlling wilt(Fusarium oxysporum) in red onion plants. The aim of the research was to know the effectiviness ofantagonism fungus of Trichoderma sp. and Gliocladium sp. in controlling wilt in red onion plants.The research used non-factorial RAK (random group design) with eight treatments: control, 10grams of F. oxysporum, 12 grams of Trichoderma sp., 18 grams of Trichoderma sp., 24 grams ofTrichoderma sp., and 12 grams ...

  5. Interaction of uranium with Pleurotus sp

    International Nuclear Information System (INIS)

    Ohnuki, Toshihiko; Sakamoto, Fuminori; Kozaki, Naofumi; Ozaki, Takuro; Samadfam, Mohammad

    2002-01-01

    Uptake of uranium by higher fungi, such as mushroom is little elucidated. We have studied the interaction of uranium with Pleurotus sp. (a mushroom) in pure culture over a wide range of U concentration (50-3000 mg/L). The Pleurotus sp. was cultured in two different media. One was rice bran medium, and the other was agar (yeast extract, peptone and dextrose) medium. The uptake of uranium in Pleurotus sp. was examined by alpha ray autoradiography (A,A), X-ray fluorescence spectroscopy (XRF) and scanning microcopy (SEM) equipped with EDS. In the agar medium, the higher uranium concentration gave lower growth of mycelia, and no fruiting body was observed. In the rice bran medium, the fruiting body was grown at U concentrations up to 1000 mg/L. The AA and XRF analysis showed that uranium taken up in the fruiting body was below the detection limit. The SEM-EDS analysis indicated that U was distributed in the limited region and was not transported to the mycelia far from U containing medium. It is concluded that uranium affects the growth of Pleurotus sp., and little uranium is taken up by Pleurotus sp. during the growth of both mycelia and fruiting body. (author)

  6. Taxonomy Icon Data: Synechocystis sp.PCC 6803 [Taxonomy Icon

    Lifescience Database Archive (English)

    Full Text Available Synechocystis sp.PCC 6803 Synechocystis sp.PCC 6803 Synechocystis_sp_PCC_6803_L.png Synecho...cystis_sp_PCC_6803_NL.png Synechocystis_sp_PCC_6803_S.png Synechocystis_sp_PCC_6803_NS.png http://bi...osciencedbc.jp/taxonomy_icon/icon.cgi?i=Synechocystis+sp%2ePCC+6803&t=L http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Synecho...cystis+sp%2ePCC+6803&t=NL http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Synecho...cystis+sp%2ePCC+6803&t=S http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Synechocystis

  7. Five novel Wickerhamomyces- and Metschnikowia-related yeast species, Wickerhamomyces chaumierensis sp. nov., Candida pseudoflosculorum sp. nov., Candida danieliae sp. nov., Candida robnettiae sp. nov. and Candida eppingiae sp. nov., isolated from plants

    NARCIS (Netherlands)

    Groenewald, Marizeth; Robert, Vincent; Smith, Maudy Th

    On the basis of nucleotide divergences in the D1/D2 domain of the 26S rRNA gene and the internal transcribed spacers (ITS) domain of the rRNA gene, five novel yeast species, Wickerhamomyces chaumierensis sp. nov. (CBS 8565(T)  = JCM 17246(T)), Candida pseudoflosculorum sp. nov. (CBS 8584(T)  = JCM

  8. SP2Bench: A SPARQL Performance Benchmark

    Science.gov (United States)

    Schmidt, Michael; Hornung, Thomas; Meier, Michael; Pinkel, Christoph; Lausen, Georg

    A meaningful analysis and comparison of both existing storage schemes for RDF data and evaluation approaches for SPARQL queries necessitates a comprehensive and universal benchmark platform. We present SP2Bench, a publicly available, language-specific performance benchmark for the SPARQL query language. SP2Bench is settled in the DBLP scenario and comprises a data generator for creating arbitrarily large DBLP-like documents and a set of carefully designed benchmark queries. The generated documents mirror vital key characteristics and social-world distributions encountered in the original DBLP data set, while the queries implement meaningful requests on top of this data, covering a variety of SPARQL operator constellations and RDF access patterns. In this chapter, we discuss requirements and desiderata for SPARQL benchmarks and present the SP2Bench framework, including its data generator, benchmark queries and performance metrics.

  9. The gamma ray spectrometer GA.SP

    Energy Technology Data Exchange (ETDEWEB)

    Bazzacco, D [Instituto Nazionale di Fisica Nucleare, Sezione di Padova, Padova (Italy)

    1992-08-01

    GA.SP is a general purpose 4{pi} detector array for advanced {gamma}-spectroscopy and, in the same time, a suitable system for reaction mechanism studies. The detector is sited at the LNL Tandem+Linac accelerator and has been built as a joint project of INFN Padova, LNL, Milano and Firenze. The array consists of 40 Compton suppressed HPGe detectors and of a 4{pi} calorimeter composed of 80 BGO crystals. The detector houses a reaction chamber of 34 cm diameter where a charged particles multiplicity filter composed of 40 Si detectors is going to be installed. Evaporation residues produced in the centre of GA.SP can be injected into the recoil mass spectrometer (RMS, named CAMEL) in use at LNL, without the need to remove any of the gamma detectors. The coupled operation of GA.SP, RMS and Si ball will give a unique instrument for identification and study of weak reaction channels. (author). 6 figs.

  10. The gamma ray spectrometer GA.SP

    International Nuclear Information System (INIS)

    Bazzacco, D.

    1992-01-01

    GA.SP is a general purpose 4π detector array for advanced γ-spectroscopy and, in the same time, a suitable system for reaction mechanism studies. The detector is sited at the LNL Tandem+Linac accelerator and has been built as a joint project of INFN Padova, LNL, Milano and Firenze. The array consists of 40 Compton suppressed HPGe detectors and of a 4π calorimeter composed of 80 BGO crystals. The detector houses a reaction chamber of 34 cm diameter where a charged particles multiplicity filter composed of 40 Si detectors is going to be installed. Evaporation residues produced in the centre of GA.SP can be injected into the recoil mass spectrometer (RMS, named CAMEL) in use at LNL, without the need to remove any of the gamma detectors. The coupled operation of GA.SP, RMS and Si ball will give a unique instrument for identification and study of weak reaction channels. (author). 6 figs

  11. SP-100/Brayton power system concepts

    International Nuclear Information System (INIS)

    Owen, D.F.

    1989-01-01

    Use of closed Brayton cycle (CBC) power conversion technology has been investigated for use with SP-100 reactors for space power systems. The CBC power conversion technology is being developed by Rockwell International under the Dynamic Isotype Power System (DIPS) and Space Station Freedom solar dynamic power system programs to provide highly efficient power conversion with radioisotype and solar collector heat sources. Characteristics including mass, radiator area, thermal power, and operating temperatures for systems utilizing SP-100 reactor and CBC power conversion technology were determined for systems in the 10-to 100-kWe power range. Possible SP-100 reactor/CBC power system configurations are presented. Advantages of CBC power conversion technology with regard to reactor thermal power, operating temperature, and development status are discussed

  12. Modifications of Sp(2) covariant superfield quantization

    Energy Technology Data Exchange (ETDEWEB)

    Gitman, D.M.; Moshin, P.Yu

    2003-12-04

    We propose a modification of the Sp(2) covariant superfield quantization to realize a superalgebra of generating operators isomorphic to the massless limit of the corresponding superalgebra of the osp(1,2) covariant formalism. The modified scheme ensures the compatibility of the superalgebra of generating operators with extended BRST symmetry without imposing restrictions eliminating superfield components from the quantum action. The formalism coincides with the Sp(2) covariant superfield scheme and with the massless limit of the osp(1,2) covariant quantization in particular cases of gauge-fixing and solutions of the quantum master equations.

  13. SP-100 converter multicouple thermoelectric cell

    International Nuclear Information System (INIS)

    Kull, R.A.; Terrill, W.R.

    1990-01-01

    The General Electric Company is under contract to DOE to design, fabricate, and test an SP-100 Ground Engineering System. This paper provides a description of the SP-100 space reactor power system configuration, and a more detailed description of the power conversion subsystem (PCSS) and the key building block of the power converter, the thermoelectric cell. The functions of the various elements of the PCSS and the cells are also presented. These cells convert the thermal energy from the reactor into electrical power at the desired voltage while being conductively coupled to the hot and cold side heat exchangers to maximize the power output and system specific power

  14. Fatty acid composition of Spirulina sp., Chlorella sp. and Chaetoceros sp. microalgae and introduction as potential new sources to extinct omega 3 and omega 6

    Directory of Open Access Journals (Sweden)

    Homan Gorjzdadeh

    2016-05-01

    Full Text Available Background: This study was carried out to determine the oil fatty acids from two special species of microalgae; Spirulina sp.,Chlorella sp. and also Chaetoceros sp. collected from Bahmanshir River. Materials and Methods: Sampling of microalgae Chaetoceros sp. from Bahmanshir River was under taken using bottle samplers during spring season of 2013. Microalgae Spirulina sp. and Chlorella sp. were supplied from Shrimp Research Institute of Iran in Bushehr Province. Samples then were cultured under controlled laboratory conditions and mass culture for 100 liters was undertaken. Isolation of microalgae species from water of cultured media was carried out using filtration and centrifugation methods. The fatty acid compositions were determined by Gas – FID chromatography. Results: Results showed that regarding Saturated Fatty Acids (SFA obtained from purified culture of Chaetoceros sp., Spirulina sp. and Chlorella sp. the maximum amount of total fatty acids were belonged to palmitic acids (C16:0 with 15.21%, 30.1% and 25.17% of total fatty acids  respectively. Analysis of Mono Unsaturated Fatty Acids (MUFA showed that in the Oleic acid was maximum amount of 34% in Spirulina sp. In addition the amount of MUFA in Chlorella sp. was 16.37% of total fatty acids. On the other hand the amount of palmeotic acid in purified culture of Chaetoceros sp. was 30.33% from total content of fatty acids. Analysis of Poly Unsaturated Fatty Acids (PUFA, Linoleic acid (C18:2 (Omega 6, revealed maximum percentage in Spirulina sp. with 18.8%. Results of Alpha linoleic acid (C18:3 (Omega3 analysis showed maximum amount of 9.66% in Chlorella sp. compared to other microalgae with lower omega 3 contents. Spirulina sp. contained maximum amount of Linoleic acid (C18:2 with 18.8% of total fatty acids. Therefore, Spirulina sp. can be considered as a rich source of omega 6 for the purpose of fatty acid extractions. The presence of PUFA in Chlorella sp. and Spirulina sp. was

  15. Harnessing the bio-mineralization ability of urease producing Serratia marcescens and Enterobacter cloacae EMB19 for remediation of heavy metal cadmium (II).

    Science.gov (United States)

    Bhattacharya, Amrik; Naik, S N; Khare, S K

    2018-06-01

    In the present study, urease positive Serratia marcescens (NCIM2919) and Enterobacter cloacae EMB19 (MTCC10649) were individually evaluated for remediation of cadmium (II) using ureolysis-induced calcium carbonate precipitation. Both the cultures were observed to efficiently remove cadmium from the media through co-precipitation of Cd (II) and Ca (II). S. marcescens and E. cloacae EMB19, respectively showed 96 and 98% removal of initial 5.0 mg L -1 soluble Cd (II) from the urea and CaCl 2 laden media at 96 h of incubation period. At higher Cd (II) concentrations of 10 and 15 mg L -1 , cadmium removal efficiency was much higher in case of E. cloacae EMB19 compared to S. marcescens. In-vitro cadmium (II) remediation study using urease containing cell-free culture supernatant of S. marcescens and E. cloacae EMB19 showed respective 98 and 53% removal of initial 50 mg L -1  Cd (II) from the reaction mixtures in co-presence of Ca (II). While in sole presence of Cd (II), only 16 and 8% removal of Cd (II) were detected for S. marcescens and E. cloacae EMB19, respectively. The elemental analysis of the co-precipitated mineral products using Energy Dispersive X-ray spectroscopy (EDX) clearly showed the prevalence of Ca and Cd ions. The morphology Cd-Ca composites formed with respect to both the cultures were observed to be of different shape and size as revealed through Scanning Electron Microscopy (SEM). Entire study hence comes out with a sustainable bioremediation option which could be effectively used to tackle Cd (II) or other heavy metal pollution. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Perturbation of formate pathway for hydrogen production by expressions of formate hydrogen lyase and its transcriptional activator in wild Enterobacter aerogenes and its mutants

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Yuan; Zhao, Hongxin; Zhang, Chong; Lai, Qiheng; Xing, Xin-Hui [Institute of Biochemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084 (China)

    2009-06-15

    To examine perturbation effects of formate pathway on hydrogen productivity in Enterobacter aerogenes (Ea), formate dehydrogenase FDH-H gene (fdhF) and formate hydrogen lyase activator protein FHLA gene (fhlA) originated from Escherichia coli, were overexpressed in the wild strain Ea, its hycA-deleted mutant (A) by knockout the formate hydrogen lyase repressor and hybO-deleted mutant (O) by knockout of the uptake hydrogenase, respectively. Overexpression of fdhF and fhlA promoted cell growth and volumetric hydrogen production rates of all the strains, and the hydrogen production per gram cell dry weight (CDW) for Ea, A and O was increased by 38.5%, 21.8% and 5.25%, respectively. The fdhF and fhlA overexpression improved the hydrogen yield per mol glucose of strains Ea and A, but declined that of strain O. The increase of hydrogen yield of the strain Ea with fdhF and fhlA expression was mainly attributed to the increase of formate pathway, while for the mutant A, the improved hydrogen yield with fdhF and fhlA expression was mainly due to the increase of NADH pathway. Analysis of the metabolites and ratio of ethanol-to-acetate showed that the cellular redox state balance and energy level were also changed for these strains by fdhF and fhlA expression. These findings demonstrated that the hydrogen production was not only dependent on the hydrogenase genes, but was also affected by the regulation of the whole metabolism. Therefore, fdhF and fhlA expression in different strains of E. aerogenes could exhibit different perturbation effects on the metabolism and the hydrogen productivity. (author)

  17. Phage-mediated Shiga toxin (Stx) horizontal gene transfer and expression in non-Shiga toxigenic Enterobacter and Escherichia coli strains.

    Science.gov (United States)

    Khalil, Rowaida K S; Skinner, Craig; Patfield, Stephanie; He, Xiaohua

    2016-07-01

    Enterobacter cloacae M12X01451 strain recently identified from a clinical specimen produces a new Stx1 subtype (Stx1e) that was not neutralized by existing anti-Stx1 monoclonal antibodies. Acquisition of stx by Ent. cloacae is rare and origin/stability of stx1e in M12X01451 is not known. In this study, we confirmed the ability of Stx1a- and Stx1e-converting phages from an Escherichia coli O157:H7 strain RM8530 and M12X01451 respectively to infect several E. coli and Ent. cloacae strains. stx1e was detected in 97.5% and 72.5% of progenies of strains lysogenized by stx1e phage after 10 (T10) and 20 (T20) subcultures, versus 65% and 17.5% for stx1a gene. Infection of M12X01451 and RM8530 with each other's phages generated double lysogens containing both phages. stx1a was lost after T10, whereas the stx1e was maintained even after T20 in M12X01451 lysogens. In RM8530 lysogens, the acquired stx1e was retained with no mutations, but 20% of stx1a was lost after T20 ELISA and western blot analyses demonstrated that Stx1e was produced in all strains lysogenized by stx1e phage; however, Stx1a was not detected in any lysogenized strain. The study results highlight the potential risks of emerging Stx-producing strains via bacteriophages either in the human gastrointestinal tract or in food production environments, which are matters of great concern and may have serious impacts on human health. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  18. A disposable electrochemical immunosensor arrays using 4-channel screen-printed carbon electrode for simultaneous detection of Escherichia coli O157:H7 and Enterobacter sakazakii

    International Nuclear Information System (INIS)

    Dou, Wenchao; Tang, Weilu; Zhao, Guangying

    2013-01-01

    An electrochemical immunosensor for Escherichia coli O157:H7 (E. coli O157:H7) and Enterobacter sakazakii (E. sakazakii) detection using carbon screen-printed low-density arrays is reported. The sensors were fabricated based on screen-printed carbon arrays containing four carbon working electrode, an integrated carbon counter electrodes and an integrated Ag/AgCl reference electrode. Multi-walled carbon nanotubes (MWCNTs)/sodium alginate (SA)/carboxymethyl chitosan (CMC) composite films were coated on all the working electrodes to enhance the sensitization of the electrode. Horseradish peroxidases (HRP) labeled antibodies of two bacteria were immobilize on different working electrode of the same screen-printed electrode respectively. The immobilization of MWCNTs, HRP labeled antibodies onto the screen-printed carbon electrodes was examined using atom force microscopy (AFM) and cyclic voltammetry (CV). The analytical performance of proposed immunosensor arrays toward E. sakazakii and E. coli O157:H7 was investigated by AFM and CV. Under optimal conditions, the linear range of E. sakazakii and E. coli O157:H7 were from 10 4 to 10 10 cfu/ml, with a detection limit of 4.57 × 10 3 cfu/ml (S/N = 3) and 3.27 × 10 3 cfu/ml (S/N = 3), respectively. The specificity, reproducibility, stability and accuracy of the proposed immunosensor arrays were also evaluated. Two antibodies modified work electrodes were tested and compared in terms of sensitivity and ability to recognize different pathogenic biological species

  19. Quantifying the effect of hand wash duration, soap use, ground beef debris, and drying methods on the removal of Enterobacter aerogenes on hands.

    Science.gov (United States)

    Jensen, Dane A; Danyluk, Michelle D; Harris, Linda J; Schaffner, Donald W

    2015-04-01

    Hand washing is recognized as a crucial step in preventing foodborne disease transmission by mitigating crosscontamination among hands, surfaces, and foods. This research was undertaken to establish the importance of several keys factors (soap, soil, time, and drying method) in reducing microorganisms during hand washing. A nonpathogenic nalidixic acid-resistant Enterobacter aerogenes surrogate for Salmonella was used to assess the efficacy of using soap or no soap for 5 or 20 s on hands with or without ground beef debris and drying with paper towel or air. Each experiment consisted of 20 replicates, each from a different individual with ∼ 6 log CFU/ml E. aerogenes on their hands. A reduction of 1.0 ± 0.4 and 1.7 ± 0.8 log CFU of E. aerogenes was observed for a 5-s wash with no soap and a 20-s wash with soap, respectively. When there was no debris on the hands, there was no significant difference between washing with and without soap for 20 s (P > 0.05). Likewise, there was no significant difference in the reductions achieved when washing without soap, whether or not debris was on the hands (P > 0.05). A significantly greater reduction (P soap when there was ground beef debris on the hands. The greatest difference (1.1 log CFU greater average reduction) in effectiveness occurred when ground beef debris was on the hands and a 20-s wash with water was compared with a 20-s wash with soap. Significantly greater (P 4.0 log CFU per towel) when hands are highly contaminated. Our results support future quantitative microbial risk assessments needed to effectively manage risks of foodborne illness in which food workers' hands are a primary cause.

  20. Treatment Outcomes in Infections Caused by "SPICE" (Serratia, Pseudomonas, Indole-positive Proteus, Citrobacter, and Enterobacter) Organisms: Carbapenem versus Noncarbapenem Regimens.

    Science.gov (United States)

    Moy, Stanley; Sharma, Roopali

    2017-01-01

    Techniques used to identify AmpC β-lactamases in SPICE (Serratia, Pseudomonas, indole-positive Proteus, Citrobacter, and Enterobacter) organisms are not yet optimized for the clinical laboratory and are not routinely used. Clinicians are often left with an uncertainty on the choice of antibiotic when a SPICE organism is isolated. The purpose of this study was to evaluate the outcomes of carbapenem versus noncarbapenem regimens in treating bacteremia or urinary tract infection from a SPICE organism in clinical practice. This single-center, retrospective, cohort study analyzed data from adult patients who had clinical infection with a SPICE organism isolated from blood or urine cultures. Patients were assigned to a carbapenem- or noncarbapenem-treated group. The primary end point was clinical response, defined as a resolution of signs and symptoms of infection at the end of therapy. A total of 332 patients were assessed, and 145 patients met the inclusion criteria for the study. There were 20 patients who received a carbapenem, while 125 received a noncarbapenem regimen. The percentage of patients who were bacteremic was 46.2%. Clinical response overall was achieved in 80% of patients on a carbapenem versus 90.3% of patients on a noncarbapenem regimen (P = 0.24). The rate of microbiologic cure was 90% in patients on a carbapenem versus 91.2% in patients on a noncarbapenem regimen (P = 1). In this study in patients treated for infection with a SPICE organism in clinical practice, the rates of clinical response did not differ significantly between the carbapenem and noncarbapenem groups. Current CLSI breakpoints set for SPICE organisms may still be reliable and may not require additional testing for AmpC β-lactamases. Copyright © 2017 Elsevier HS Journals, Inc. All rights reserved.

  1. Characterization of quinolone-resistant Enterobacteriaceae strains isolated from poultry in Western Algeria: First report of qnrS in an Enterobacter cloacae

    Directory of Open Access Journals (Sweden)

    Qada Benameur

    2018-04-01

    Full Text Available Aim: Multidrug-resistant (MDR Enterobacteriaceae have frequently been reported, in both human and veterinary medicine, from different parts of the world as a consequence of antibiotic usage. However, there is a lack of published data regarding antimicrobial resistance in non-Escherichia coli (E. coli Enterobacteriaceae from animals in Algeria. This study aimed to evaluate the frequency of resistance to antibiotics with a focus on quinolones and to investigate the presence of qnr genes in Enterobacteriaceae of poultry origin. Materials and Methods: A total of 310 samples of poultry origin were collected from 2010 to 2014 from broiler and layer farms and hatcheries located in different geographic areas of Western Algeria (including Mostaganem, Oran, Mascara, Relizane, Chlef, Tiaret, and Tissemsilt. Antimicrobial susceptibility testing was performed using disc diffusion assay. Polymerase chain reaction and sequencing accomplished the characterization of qnr genes (qnrA, qnrB, and qnrS. Results: A total of 253 Enterobacteriaceae strains were isolated in this study. These isolates exhibited high levels of resistance to quinolones and other families of antibiotics. All the strains isolated in this study were resistant to at least one antibiotic. Among them, 233 (92.09% were considered MDR. Among the 18 randomly selected nalidixic acid (NA- resistant Enterobacteriaceae isolates, one E. coli and one Enterobacter cloacae were carrying qnrS1. By contrast, qnrA and qnrB were not detected in this study. Conclusion: This is the first report on the identification of the qnrS gene in E. cloacae isolated from animal source in Algeria. Further studies have to be conducted to determine the real prevalence of qnr genes.

  2. Halobacterium sp. SP1(1) as a starter culture for accelerating fish sauce fermentation.

    Science.gov (United States)

    Akolkar, A V; Durai, D; Desai, A J

    2010-07-01

    Application of Halobacterium sp. SP1(1) for the acceleration of fish sauce fermentation. Traditional fish sauce fermentation was mimicked using Halobacterium sp. SP1(1) as starter culture. Protease activity, peptide release and α-amino content (parameters used to monitor the progress of the fermentation) were high at day 10 in tests and day 20 in un-inoculated controls. The total protein and nitrogen contents were also high in tests compared with controls. The amino acid profile observed at the end of fermentation in experimental samples, when compared with the commercial sauce preparation, was found to be better with respect to flavour and aroma contributing amino acids as well as essential amino acid lysine. Microflora analysis of the final fish sauce revealed the absence of any nonhalophilic or halotolerant micro-organisms. The protease-producing halophilic isolates obtained from the fish sauce of eviscerated and uneviscerated controls were identified as Halobacterium sp. F1 and F2, respectively, by 16S rDNA sequence analysis. Exogenous augmentation of Halobacterium sp. SP1(1) accelerated the fish sauce fermentation process with an additive effect on the existing natural microflora present in the fish during fermentation. Halobacterium sp SP1(1), therefore, can be used as an important starter culture for accelerating the fish fermentation process, which is attributed to its extracellular protease. The present study is the first report on use of Halobacterium species as a starter culture for accelerating fish sauce fermentation. Use of halobacterial starter cultures may revolutionize the process in fish sauce industries by reducing the fermentation time and making the process more economical with improved nutritive value of product. Journal compilation © 2009 The Society for Applied Microbiology. No claim to Indian Government works.

  3. 76 FR 56876 - Proposed Collection; Comment Request for Forms 9779, 9779(SP), 9783, 9783(SP), 9787, 9787(SP...

    Science.gov (United States)

    2011-09-14

    ... and 9789(SP), Electronic Federal Tax Payment System (EFTPS). DATES: Written comments should be received on or before November 14, 2011 to be assured of consideration. ADDRESSES: Direct all [email protected] . SUPPLEMENTARY INFORMATION: Title: Electronic Federal Tax Payment System (EFTPS). OMB...

  4. SP-A binding sites on bovine alveolar macrophages.

    Science.gov (United States)

    Plaga, S; Plattner, H; Schlepper-Schaefer, J

    1998-11-25

    Surfactant protein A (SP-A) binding to bovine alveolar macrophages was examined in order to characterize SP-A binding proteins on the cell surface and to isolate putative receptors from these cells that could be obtained in large amounts. Human SP-A, unlabeled or labeled with gold particles, was bound to freshly isolated macrophages and analyzed with ELISA or the transmission electron microscope. Binding of SP-A was inhibited by Ca2+ chelation, by an excess of unlabeled SP-A, or by the presence of 20 mg/ml mannan. We conclude that bovine alveolar macrophages expose binding sites for SP-A that are specific and that depend on Ca2+ and on mannose residues. For isolation of SP-A receptors with homologous SP-A as ligand we isolated SP-A from bovine lung lavage. SDS-PAGE analysis of the purified SP-A showed a protein of 32-36 kDa. Functional integrity of the protein was demonstrated. Bovine SP-A bound to Dynabeads was used to isolate SP-A binding proteins. From the fractionated and blotted proteins of the receptor preparation two proteins bound SP-A in a Ca2+-dependent manner, a 40-kDa protein showing mannose dependency and a 210-kDa protein, showing no mannose sensitivity. Copyright 1998 Academic Press.

  5. Ovos de Toxocara sp. e larvas de Ancylostoma sp. em praça pública de Lavras, MG Toxocara sp. eggs and Ancylostoma sp. larva in public parks, Brazil

    Directory of Open Access Journals (Sweden)

    Antônio Marcos Guimarães

    2005-04-01

    Full Text Available Larva migrans visceral e cutânea são zoonoses parasitárias causadas pela infecção da larva de Toxocara sp. e Ancylostoma sp., respectivamente. O objetivo do estudo foi verificar a contaminação por ovos de Toxocara sp. e ovos e larvas de Ancylostoma sp. em amostras de solos coletadas de praças públicas e de áreas de recreação infantil de Lavras, Estado de Minas Gerais, por meio da técnica de centrífugo-flutuação e do método de Baermann. A ocorrência de ovos de Toxocara sp. e, ovos e larvas de Ancylostoma sp. foi observada em 69,6% (16/23 das amostras de solo coletadas de praças públicas. A contaminação somente por ovos de Ancylostoma sp. em amostras de solo coletadas em escolas/creches foi de 22,2% (4/18. A percentagem de amostras de areia coletadas de escolas/creches contaminadas somente com larvas de Ancylostoma sp. foi de 11,1% (2/18. Praças públicas são as áreas com maior risco potencial de infecção por Toxocara sp. e Ancylostoma sp. Exame coproparasitológico realizado em 174 amostras de fezes de cães observou 58% e 23%, respectivamente, com ovos de Ancylostoma sp. e Toxocara sp.Visceral and cutaneous larva migrans are parasitic zoonoses caused by the infection of larval nematodes Toxocara sp. and Ancylostoma sp. respectively. The objective of this study was to investigate the contamination by Toxocara sp. eggs and Ancylostoma sp. eggs and larva of soil samples collected from public parks and children's playground areas in state of Minas Gerais, Brazil, using both Baermann's method and centrifugal flotation technique. Toxocara sp. and Ancylostoma sp. eggs were observed in soil samples collected from public squares in 17.4% (4/23 and 69.6 (16/23 respectively. In schools and child day care settings the contamination by Ancylostoma sp. larva in sand samples was 11.1% (2/18. Public parks are settings of more potential risk of Toxocara sp. eggs and Ancylostoma sp. infection. Stool parasitology testing of 174 stool

  6. ‘Khelaifiella massiliensis’, ‘Niameybacter massiliensis’, ‘Brachybacterium massiliense’, ‘Enterobacter timonensis’, ‘Massilibacillus massiliensis’, new bacterial species and genera isolated from the gut microbiota of healthy infants

    Directory of Open Access Journals (Sweden)

    M. Tidjani Alou

    2017-09-01

    Full Text Available The main characteristics of ‘Khelaifiella massiliensis’ strain Mt13T (= CSUR P1935, = DSM100591, ‘Niameybacter massiliensis’ strain Mt14T (= CSUR P1909, = DSM100592, ‘Brachybacterium massiliense’ strain MT5T (= CSUR P2240, = DSM101766, ‘Enterobacter timonensis’ strain mt20T (= CSUR P2201, = DSM 101775 and ‘Massilibacillus massiliensis’ strain Marseille-P2411T (= CSUR P2411, = DSM102838, new species isolated from the gut of healthy African infants, are presented.

  7. Concordância dos resultados do sistema BD Phoenix com provas bioquímicas manuais na identificação de Enterobactérias em amostras clínicas

    Directory of Open Access Journals (Sweden)

    Natacha Allgayer

    2015-02-01

    Full Text Available Enterobactérias pertencem a um grupo grande e heterogêneo de bacilos Gram-negativos cujo habitat natural é o cólon de humanos e animais, sendo microrganismos amplamente distribuídos na natureza. Devido a essas características são frequentemente responsáveis por infecções hospitalares. O principal objetivo desse estudo foi estabelecer uma concordância entre as provas bioquímicas manuais e a automação BD Phoenix 100 na identificação de enterobactérias, a partir de uma análise de registros de pacientes hospitalizados. No período de Agosto de 2011 a Abril de 2012, foram realizados 303 exames no Laboratório Exame de Análises Clinicas pelo método manual e pela automação. Do total, 27,7% foram positivos para enterobactérias. Os microrganismos mais frequentes isolados, foram a Klebsiella pneumoniae 36,9%, seguido pela Escherichia coli 29,8%. O estudo apresentou uma alta concordância entre os métodos, principalmente na identificação dos gêneros. Na identificação das espécies, as bactérias dos gêneros Klebsiella spp. e Serratia spp. não tiveram suas espécies identificadas pelo método manual em sete dos registros observados, sendo identificadas somente pela automação. Assim como a Escherichia coli que não foi identificada pelo método manual, vista como indeterminada em quatro dos registros analisados. Portanto, verificou-se uma boa concordância entre os métodos na identificação das principais enterobactérias isoladas de amostras clínicas.

  8. Gilliamella intestini sp. nov., Gilliamella bombicola sp. nov., Gilliamella bombi sp. nov. and Gilliamella mensalis sp. nov.: Four novel Gilliamella species isolated from the bumblebee gut.

    Science.gov (United States)

    Praet, Jessy; Cnockaert, Margo; Meeus, Ivan; Smagghe, Guy; Vandamme, Peter

    2017-06-01

    Spectra of five isolates (LMG 28358 T , LMG 29879 T , LMG 29880 T , LMG 28359 T and R-53705) obtained from gut samples of wild bumblebees of Bombus pascuorum, Bombus lapidarius and Bombus terrestris were grouped into four MALDI-TOF MS clusters. RAPD analysis revealed an identical DNA fingerprint for LMG 28359 T and R-53705 which also grouped in the same MALDI-TOF MS cluster, while different DNA fingerprints were obtained for the other isolates. Comparative 16S rRNA gene sequence analysis of the four different strains identified Gilliamella apicola NCIMB 14804 T as nearest neighbour species. Average nucleotide identity values of draft genome sequences of the four isolates and of G. apicola NCIMB 14804 T were below the 96% threshold value for species delineation and all four strains and G. apicola NCIMB 14804 T were phenotypically distinct. Together, the draft genome sequences and phylogenetic and phenotypic data indicate that the four strains represent four novel Gilliamella species for which we propose the names Gilliamella intestini sp. nov., with LMG 28358 T as the type strain, Gilliamella bombicola sp. nov., with LMG 28359 T as the type strain, Gilliamella bombi sp. nov., with LMG 29879 T as the type strain and Gilliamella mensalis sp. nov., with LMG 29880 T as the type strain. Copyright © 2017 Elsevier GmbH. All rights reserved.

  9. Biosorption of uranium by Azolla, SP, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Vieira, Ludmila C.; Alves, Eliakim G.; Marumo, Julio T., E-mail: lcvieira@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Ferreira, Rafael V. de P., E-mail: rafael@itatijuca.com [Itatijuca Biotech, Sao Paulo, SP (Brazil); Canevesi, Rafael L.S.; Silva, Edson A., E-mail: edson.silva2@unioeste.br [Universidade Estadual do Oeste Parana (UNIOESTE), Toledo, PR (Brazil)

    2015-07-01

    Radioactive liquid waste needs special attention and requires suitable treatment before deposition. Among the potential technologies under development for the treatment of liquid radioactive wastes the biosorption has been highlighted by being an efficient and low cost technique. Biosorption process involves the exchange of ions contained in the biomass matrix by others present in solution. There are many biomasses that could be applied in treatment of radioactive wastes, for example, agricultural residues and macrophyte. The aim of this study is evaluate the ability of the Azolla sp., a floating aquatic plant, to absorb uranium in solution. Azolla sp. is a macrophyte that has been used to treat effluents containing heavy metals. The biosorption capacity of uranium by Azolla sp. was experimentally determined and modeled by isotherms. Experiments were performed to determine metal uptake, and then the solutions were analyzed by inductively coupled plasma optical emission spectrometry (ICP-OES). The isotherms applied to model the data was Langmuir, Freundlich, Sips Toth, Redlich Peternson, Two-Site-Langmuir, Radke Prausnitz to develop a technique for the treatment of radioactive liquid waste generated at the Nuclear and Energy Research Institute (IPEN-CNEN/SP), Brazil. (author)

  10. Biosorption of uranium by Azolla, SP, Brazil

    International Nuclear Information System (INIS)

    Vieira, Ludmila C.; Alves, Eliakim G.; Marumo, Julio T.; Ferreira, Rafael V. de P.; Canevesi, Rafael L.S.; Silva, Edson A.

    2015-01-01

    Radioactive liquid waste needs special attention and requires suitable treatment before deposition. Among the potential technologies under development for the treatment of liquid radioactive wastes the biosorption has been highlighted by being an efficient and low cost technique. Biosorption process involves the exchange of ions contained in the biomass matrix by others present in solution. There are many biomasses that could be applied in treatment of radioactive wastes, for example, agricultural residues and macrophyte. The aim of this study is evaluate the ability of the Azolla sp., a floating aquatic plant, to absorb uranium in solution. Azolla sp. is a macrophyte that has been used to treat effluents containing heavy metals. The biosorption capacity of uranium by Azolla sp. was experimentally determined and modeled by isotherms. Experiments were performed to determine metal uptake, and then the solutions were analyzed by inductively coupled plasma optical emission spectrometry (ICP-OES). The isotherms applied to model the data was Langmuir, Freundlich, Sips Toth, Redlich Peternson, Two-Site-Langmuir, Radke Prausnitz to develop a technique for the treatment of radioactive liquid waste generated at the Nuclear and Energy Research Institute (IPEN-CNEN/SP), Brazil. (author)

  11. Carbon sp chains in graphene nanoholes

    DEFF Research Database (Denmark)

    Castelli, Ivano Eligio; Ferri, Nicola; Onida, Giovanni

    2012-01-01

    Nowadays sp carbon chains terminated by graphene or graphitic-like carbon are synthesized routinely in several nanotech labs. We propose an ab initio study of such carbon-only materials, by computing their structure and stability, as well as their electronic, vibrational and magnetic properties. ...

  12. Rhodotorula bloemfonteinensis sp. nov., Rhodotorula eucalyptica sp. nov., Rhodotorula orientis sp. nov. and Rhodotorula pini sp. nov., yeasts isolated from monoterpene-rich environments.

    Science.gov (United States)

    Pohl, Carolina H; Smit, Martha S; Albertyn, Jacobus

    2011-09-01

    Recent rDNA sequencing of 25 isolates from a previous study, during which limonene-utilizing yeasts were isolated from monoterpene-rich environments by using 1,4-disubstituted cyclohexanes as sole carbon sources, led to the identification of four hitherto unknown Rhodotorula species. Analyses of the 26S rDNA D1/D2 region as well as the internal transcribed spacer (ITS) domain indicated that two isolates (CBS 8499(T) and CBS 10736) were identical and were closely related to Rhodotorula cycloclastica, a previously described limonene-utilizing yeast. These novel isolates differed from known yeast species and could be distinguished from R. cycloclastica by standard physiological tests. The other three isolates represent three novel Rhodotorula species, closely related to Sporobolomyces magnisporus. These three species could also be distinguished from other Rhodotorula species by standard physiological tests. Based on these results, we suggest that the new isolates represent novel species, for which the names Rhodotorula eucalyptica sp. nov. (type strain CBS 8499(T)  = NRRL Y-48408(T)), Rhodotorula pini sp. nov. (type strain CBS 10735(T)  = NRRL Y-48410(T)), Rhodotorula bloemfonteinensis sp. nov. (type strain CBS 8598(T)  = NRRL Y-48407(T)) and Rhodotorula orientis sp. nov. (type strain CBS 8594(T)  = NRRL Y-48719(T)) are proposed. R. eucalyptica and R. pini can also utilize limonene.

  13. Test af spørgeskema

    DEFF Research Database (Denmark)

    Hermansen, Jonathan

    2017-01-01

    Denne bog gennemgår alle surveyarbejdets faser og giver en praktisk indføring i •design af undersøgelsen og udvælgelse af stikprøver, •formulering af spørgeskemaer samt indsamling og kodning af data, •metoder til at analysere resultaterne....

  14. Lipid contents of the sponge Haliclona sp.

    Digital Repository Service at National Institute of Oceanography (India)

    Parameswaran, P.S.; Das, B.; Kamat, S.Y.

    Several fatty acids, sterols, batyl alcohol and its analogs and an N-acylated sphingosine (ceramide) have been isolated from the lipid fraction of the extract of the sponge Haliclona sp. The major sterol is found to be cholesterol (54%), followed...

  15. Optisk scanning af spørgeskemaer

    DEFF Research Database (Denmark)

    Paulsen, Aksel

    / 1000 felter= 0.370 (95% CI: 0.160-0.729), (p= 0.020)). Der var ingen statistisk forskel mellem optisk scanning (fejl/ 1000 felter= 0.046 (95% CI: 0.001-0.258)) og manuel dobbelt indtastning (p=1.000). Konklusioner: Optisk scanning er et godt alternativ til manuel dobbelt indtastning for spørgeskema med......Formål og baggrund: Patient rapporterede outcomes i form af spørgeskemaer bruges i øgende grad i sundhedssektoren både i klinisk praksis og forskning. Ofte bruges spørgeskemaer i papirformat. Manuel dobbelt indtastning er defineret som guld standard for overføring af data til et elektronisk format......, men processen er tidkrævende. Optisk scanning af spørgeskemaer med automatisk registrering af svar kan være et alternativ, men videre validering af metoden er nødvendig. Design: 200 patienter blev tilfældigt udvalgt fra en kohorte på 5777 patienter der tidligere havde svaret på to forskellige...

  16. Aerococcus sp. with an antimycobacterial effect

    African Journals Online (AJOL)

    Yomi

    2011-12-21

    Dec 21, 2011 ... In this study, we reported data on a strain that was isolated from different areas of Fez. (Morocco), which ... sp. The antibacterial activity of the genus Aerococcus have .... able to amplify the 16S rRNA gene from eubacteria.

  17. Botrallin from the endophytic fungus Hyalodendriella sp ...

    African Journals Online (AJOL)

    use

    2011-12-12

    Dec 12, 2011 ... Bioassay-guided fractionation of the crude methanol extract of the mycelia from the endophytic fungus. Hyalodendriella sp. Ponipodef12, associated with the hybrid 'Neva' of Populus deltoides Marsh × P. nigra L., led to the isolation of one compound coded as P12-1 which was identified as botrallin (1,7-.

  18. The astaxanthin dideoxyglycoside biosynthesis pathway in Sphingomonas sp. PB304

    DEFF Research Database (Denmark)

    Kim, Se Hyeuk; Kim, Jin Ho; Lee, Bun Yeol

    2014-01-01

    A major carotenoid in Sphingomonas sp. PB304, originally isolated from a river in Daejon City, South Korea, was identified as astaxanthin dideoxyglycoside. Gene clusters encoding the astaxanthin dideoxyglycoside biosynthetic enzymes were identified by screening Sphingomonas sp. PB304 fosmid...

  19. SP-100 initial startup and restart control strategy

    Science.gov (United States)

    Halfen, Frank J.; Wong, Kwok K.; Switick, Dennis M.; Shukla, Jaikaran N.

    Startup control strategies for SP-100 are described. Revised control and operating strategies are discussed which have been developed and tested using the SP-100 dynamic simulation model Aries-GFS (Generic Flight System).

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

    Science.gov (United States)

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

    2002-05-01

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

  1. Analisis Fosfor pada Cacing Tanah (Megascolex sp. dan Fridericia sp.) Secara Spektrofotometri Sinar Tampak

    OpenAIRE

    Safira, Cut Shafa

    2015-01-01

    Earthworm is natural resource which can be used for medication due to its highly amount of minerals. One of these minerals is phosphorus. The aim of this research are to identify, determine and know the difference content of phosphorus in Megascolex sp. and Fridericia sp. Qualitative analysis shows positive results with addition of ammonium molybdate 4% and BaCl2 5%. Quantitative analysis was done using visible spectrophotometer with ascorbic acid method, measuring blu-colored molybdenum ...

  2. Nanocrystalline sp{sup 2} and sp{sup 3} carbons: CVD synthesis and applications

    Energy Technology Data Exchange (ETDEWEB)

    Terranova, M. L. [Università degli Studi di Roma “Tor Vergata,” via Della Ricerca Scientifica, Dipartimento di Scienze e Tecnologie Chimiche—MinimaLab (Italy); Rossi, M. [Università degli Studi di Roma “Sapienza,” via A. Scarpa, Dipartimento di Scienze di Base e Applicate per l’Ingegneria and Centro di Ricerca per le Nanotecnologie Applicate all’Ingegneria (CNIS) (Italy); Tamburri, E., E-mail: emanuela.tamburri@uniroma2.it [Università degli Studi di Roma “Tor Vergata,” via Della Ricerca Scientifica, Dipartimento di Scienze e Tecnologie Chimiche—MinimaLab (Italy)

    2016-11-15

    The design and production of innovative materials based on nanocrystalline sp{sup 2}- and sp{sup 3}-coordinated carbons is presently a focus of the scientific community. We present a review of the nanostructures obtained in our labs using a series of synthetic routes, which make use of chemical vapor deposition (CVD) techniques for the selective production of non-planar graphitic nanostructures, nanocrystalline diamonds, and hybrid two-phase nanostructures.

  3. Differences in nutrient uptake capacity of the benthic filamentous algae Cladophora sp., Klebsormidium sp. and Pseudanabaena sp. under varying N/P conditions.

    Science.gov (United States)

    Liu, Junzhuo; Vyverman, Wim

    2015-03-01

    The N/P ratio of wastewater can vary greatly and directly affect algal growth and nutrient removal process. Three benthic filamentous algae species Cladophora sp., Klebsormidium sp. and Pseudanabaena sp. were isolated from a periphyton bioreactor and cultured under laboratory conditions on varying N/P ratios to determine their ability to remove nitrate and phosphorus. The N/P ratio significantly influenced the algal growth and phosphorus uptake process. Appropriate N/P ratios for nitrogen and phosphorus removal were 5-15, 7-10 and 7-20 for Cladophora sp., Klebsormidium sp. and Pseudanabaena sp., respectively. Within these respective ranges, Cladophora sp. had the highest biomass production, while Pseudanabaena sp. had the highest nitrogen and phosphorus contents. This study indicated that Cladophora sp. had a high capacity of removing phosphorus from wastewaters of low N/P ratio, and Pseudanabaena sp. was highly suitable for removing nitrogen from wastewaters with high N/P ratio. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Anomalous self potential (sp) log signatures observed in a water ...

    African Journals Online (AJOL)

    Geophysical logging was done after drilling had been completed in a water well at Okwudor, South Eastern Nigeria. Three electric logs were run viz: Self Potential (SP), Resistivity N16″ and N64″ logs. An anomaly was observed in the SP log. The SP results from this well show some deviation from the standard norm.

  5. Biosorption of chromium by mangrove-derived Aplanochytrium sp ...

    African Journals Online (AJOL)

    The microbial dried biomass of Thraustochytrids is used as bioadsorbent for the removal of the chromium in aqueous solution. In this investigation, three species of Thraustochydrids namely Aplanochytrium sp., Thraustochytrium sp. and Schizochytrium sp. were tested for the efficiency of chromium accumulation by culturing ...

  6. Babesia peircei sp. nov. from the jackass penguin

    African Journals Online (AJOL)

    1992-01-09

    Jan 9, 1992 ... An avian piroplasm, Babesia peircei sp. nov. is described from the jackass penguin Spheniscus demersus. Morphological differences between Babesia peircei sp. nov. and the other valid Babesia spp. are discussed together with the possible vectors. 'n Voal-piroplasma, Babesia peircei sp. nov. afkomstig ...

  7. Environmental conditions affecting exopolysaccharide production by Pseudomonas aeruginosa, Micrococcus sp., and Ochrobactrum sp.

    Science.gov (United States)

    Kiliç, Nur Koçberber; Dönmez, Gönül

    2008-06-15

    Three different chromium-resistant microorganisms (Pseudomonas aeruginosa, Micrococcus sp., and Ochrobactrum sp.) were tested with regard to their EPS production at different pH levels, temperatures, Cr(VI) concentrations, and incubation periods. The optimum pH level was 7 for P. aeruginosa and Micrococcus sp., while it was 8 for Ochrobactrum sp. according to the highest EPS amount at 100 mg/L Cr(VI) concentration. The highest production of EPSs by the three bacteria was obtained under different environmental conditions. P. aeruginosa produced the highest EPS (863.3 mg/L) after incubation for 96 h on media with 50 mg/L Cr(VI) at 20 degrees C, Micrococcus sp. gave the highest yield (444.6 mg/L) after incubation for 72 h on media with 100 mg/L Cr(VI) at the same temperature, and Ochrobactrum sp. had the highest production (430.5 mg/L) on media with 150 mg/L Cr(VI) at 30 degrees C at the end of 48 h of incubation.

  8. Remote sensing data of SP Mountain and SP Lava flow in North-Central Arizona

    Science.gov (United States)

    Schaber, G.G.; Elachi, C.; Farr, T.G.

    1980-01-01

    Multifrequency airborne radar image data of SP Mountain [Official name of feature (U.S. Geological Survey, 1970)] and SP flow (and vicinity) in north-central Arizona were obtained in diverse viewing directions and direct and cross-polarization, then compared with surface and aerial photography, LANDSAT multispectral scanner data, airborne thermal infrared imagery, surface geology, and surface roughness statistics. The extremely blocky, basaltic andesite of SP flow is significantly brighter on direct-polarization K-band (0.9-cm wavelength) images than on cross-polarized images taken simultaneously. Conversely, for the longer wavelength (25 cm) L-band radar images, the cross-polarization image returns from SP flow are brighter than the direct-polarized image. This effect is explained by multiple scattering and the strong wavelength dependence of polarization effects caused by the rectilinear basaltic andesite scatters. Two distinct types of surface relief on SP flow, one extremely blocky, the other subdued, are found to be clearly discriminated on the visible and thermal wavelength images but are separable only on the longer wavelength L-band radar image data. The inability of the K- and X- (3-cm wavelength) band radars to portray the differences in roughness between the two SP flow surface units is attributed to the radar frequency dependence of the surface-relief scale, which, described as the Rayleigh criterion, represents the transition between quasispecular and primarily diffuse backscatter. ?? 1980.

  9. Two new species of suctorians, Acineta satyanandani sp. nov. and Paracineta karunakarani sp. nov. epizoic on ostracods

    Digital Repository Service at National Institute of Oceanography (India)

    Santhakumari, V.

    Two, species of protozoic suctorians, Acineta satyanandani sp. nov. and Paracineta karunakarani sp. nov., are described. These were found attached on the body of the marine ostracod, Cypridina dentata (Muller), collected from the shelf and slope...

  10. Microbiologically influenced corrosion of galvanized steel by Desulfovibrio sp. and Desulfosporosinus sp. in the presence of Ag–Cu ions

    Energy Technology Data Exchange (ETDEWEB)

    Ilhan-Sungur, Esra, E-mail: esungur@istanbul.edu.tr [Istanbul University, Faculty of Science, Department of Biology, 34134 Vezneciler, Istanbul (Turkey); Unsal-Istek, Tuba [Istanbul University, Faculty of Science, Department of Biology, 34134 Vezneciler, Istanbul (Turkey); Cansever, Nurhan [Yıldız Technical University, Faculty of Chemistry-Metallurgy, Metallurgical and Materials Engineering Department, 34210 Esenler, Istanbul (Turkey)

    2015-07-15

    The effects of Ag–Cu ions on the microbiologically induced corrosion of galvanized steel in the presence of Desulfovibrio sp. and Desulfosporosinus sp. were investigated. The corrosion behavior of galvanized steel was analyzed by potentiodynamic polarization and electrochemical impedance spectroscopy. The biofilm, corrosion products and Ag–Cu ions on the surfaces were investigated by using scanning electron microscopy, energy dispersive X-ray spectrometry and elemental mapping. The biofilm layer formed by the Desulfovibrio sp. was stable covering the all surface of galvanized steel coupons, while that by Desulfosporosinus sp. was intermittent, highly porous and heterogeneous. It was found that both of the sulfate reducing bacteria species accelerated corrosion of the galvanized steel. However, it was detected that Desulfosporosinus sp. was more corrosive for galvanized steel than Desulfovibrio sp. Scanning electron microscopy images showed that Desulfovibrio sp. and Desulfosporosinus sp. in biofilm clustered into patches on the galvanized steel surface when the culture contained toxic Ag–Cu ions. The ions affected the growth of the sulfate reducing bacteria strains in different ways and hence the corrosion behaviors. It was observed that the Ag–Cu ions affected negatively growth of Desulfosporosinus sp. especially after 24 h of exposure leading to a decrease in the corrosion rate of galvanized steel. However, Desulfovibrio sp. showed more corrosive effect in the presence of the ions according to the ions-free culture. Energy dispersive X-ray spectrometry analysis showed that corrosion products on the surfaces were mainly composed of Zn, S, Na, O and P. - Highlights: • Galvanized steel was corroded by Desulfosporosinus sp. and Desulfovibrio sp. • Desulfosporosinus sp. is more corrosive than Desulfovibrio sp. • The Ag–Cu ions affected corrosion behavior of Desulfosporosinus sp. and Desulfovibrio sp. on galvanized steel.

  11. In vitro cytotoxicity evaluation of nano-carbon particles with different sp{sup 2}/sp{sup 3} ratios

    Energy Technology Data Exchange (ETDEWEB)

    Li, S.S.; Wu, B.J.; Deng, Q.Y. [Key Laboratory for Advanced Technologies of Materials, Ministry of Education, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, Sichuan 610031 (China); Guo, Y.B. [The Third People' s Hospital of Chengdu, Sichuan 610031 (China); Leng, Y.X., E-mail: yxleng@263.net [Key Laboratory for Advanced Technologies of Materials, Ministry of Education, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, Sichuan 610031 (China); Huang, N. [Key Laboratory for Advanced Technologies of Materials, Ministry of Education, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, Sichuan 610031 (China)

    2017-06-01

    Graphitization occurs during the long-term service of a diamond-like carbon (DLC) modified artificial joint. Then, DLC wear debris, which are carbon particles with different sp{sup 2}/sp{sup 3} ratios and sizes ranging from the nano- to micro-meter scale produced. In this paper, to promote the application of DLC coating for artificial joint modification, the cytotoxicity of DLC debris (nano-carbon particles, NCs) with different sp{sup 2}/sp{sup 3} ratios was studied. The microstructure and physical characteristics of NCs with different sp{sup 2}/sp{sup 3} ratios were investigated by Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), Transmission Electron Microscope (TEM) and Dynamic Light Scattering (DLS). Meanwhile, osteoblasts and macrophages were applied to characterize the cytotoxicity of the NCs. In vitro cytotoxicity assay results indicated that cells incubated with NCs of different sp{sup 2}/sp{sup 3} ratios had greater osteogenic capacity, and these particles caused a weaker immune response in comparison with CoCrMo particles. Taken together, the results indicated that NCs with different sp{sup 2}/sp{sup 3} ratios presented a good cytocompatibility than CoCrMo particles. But no significant differences were observed among NCs with different sp{sup 2}/sp{sup 3} ratios. The better cytocompatibility of NCs is mainly attributable to their surface charge. - Highlights: • NCs with different sp{sup 2}/sp{sup 3} ratios have been successfully prepared by annealing treatment. • NCs with different sp{sup 2}/sp{sup 3} ratios show good osteogenic capacity and lower immune response. • The good cytocompatibility of NCs is mainly dependent on its surface charge.

  12. Microbiologically influenced corrosion of galvanized steel by Desulfovibrio sp. and Desulfosporosinus sp. in the presence of Ag–Cu ions

    International Nuclear Information System (INIS)

    Ilhan-Sungur, Esra; Unsal-Istek, Tuba; Cansever, Nurhan

    2015-01-01

    The effects of Ag–Cu ions on the microbiologically induced corrosion of galvanized steel in the presence of Desulfovibrio sp. and Desulfosporosinus sp. were investigated. The corrosion behavior of galvanized steel was analyzed by potentiodynamic polarization and electrochemical impedance spectroscopy. The biofilm, corrosion products and Ag–Cu ions on the surfaces were investigated by using scanning electron microscopy, energy dispersive X-ray spectrometry and elemental mapping. The biofilm layer formed by the Desulfovibrio sp. was stable covering the all surface of galvanized steel coupons, while that by Desulfosporosinus sp. was intermittent, highly porous and heterogeneous. It was found that both of the sulfate reducing bacteria species accelerated corrosion of the galvanized steel. However, it was detected that Desulfosporosinus sp. was more corrosive for galvanized steel than Desulfovibrio sp. Scanning electron microscopy images showed that Desulfovibrio sp. and Desulfosporosinus sp. in biofilm clustered into patches on the galvanized steel surface when the culture contained toxic Ag–Cu ions. The ions affected the growth of the sulfate reducing bacteria strains in different ways and hence the corrosion behaviors. It was observed that the Ag–Cu ions affected negatively growth of Desulfosporosinus sp. especially after 24 h of exposure leading to a decrease in the corrosion rate of galvanized steel. However, Desulfovibrio sp. showed more corrosive effect in the presence of the ions according to the ions-free culture. Energy dispersive X-ray spectrometry analysis showed that corrosion products on the surfaces were mainly composed of Zn, S, Na, O and P. - Highlights: • Galvanized steel was corroded by Desulfosporosinus sp. and Desulfovibrio sp. • Desulfosporosinus sp. is more corrosive than Desulfovibrio sp. • The Ag–Cu ions affected corrosion behavior of Desulfosporosinus sp. and Desulfovibrio sp. on galvanized steel

  13. Interaction of Sp1 zinc finger with transport factor in the nuclear localization of transcription factor Sp1

    International Nuclear Information System (INIS)

    Ito, Tatsuo; Kitamura, Haruka; Uwatoko, Chisana; Azumano, Makiko; Itoh, Kohji; Kuwahara, Jun

    2010-01-01

    Research highlights: → Sp1 zinc fingers themselves interact with importin α. → Sp1 zinc finger domains play an essential role as a nuclear localization signal. → Sp1 can be transported into the nucleus in an importin-dependent manner. -- Abstract: Transcription factor Sp1 is localized in the nucleus and regulates the expression of many cellular genes, but the nuclear transport mechanism of Sp1 is not well understood. In this study, we revealed that GST-fused Sp1 protein bound to endogenous importin α in HeLa cells via the Sp1 zinc finger domains, which comprise the DNA binding domain of Sp1. It was found that the Sp1 zinc finger domains directly interacted with a wide range of importin α including the armadillo (arm) repeat domain and the C-terminal acidic domain. Furthermore, it turned out that all three zinc fingers of Sp1 are essential for binding to importin α. Taken together, these results suggest that the Sp1 zinc finger domains play an essential role as a NLS and Sp1 can be transported into the nucleus in an importin-dependent manner even though it possesses no classical NLSs.

  14. A superhard sp3 microporous carbon with direct bandgap

    Science.gov (United States)

    Pan, Yilong; Xie, Chenlong; Xiong, Mei; Ma, Mengdong; Liu, Lingyu; Li, Zihe; Zhang, Shuangshuang; Gao, Guoying; Zhao, Zhisheng; Tian, Yongjun; Xu, Bo; He, Julong

    2017-12-01

    Carbon allotropes with distinct sp, sp2, and sp3 hybridization possess various different properties. Here, a novel all-sp3 hybridized tetragonal carbon, namely the P carbon, was predicted by the evolutionary particle swarm structural search. It demonstrated a low density among all-sp3 carbons, due to the corresponding distinctive microporous structure. P carbon is thermodynamically stable than the known C60 and could be formed through the single-walled carbon nanotubes (SWCNTs) compression. P carbon is a direct bandgap semiconductor displaying a strong and superhard nature. The unique combination of electrical and mechanical properties constitutes P carbon a potential superhard material for semiconductor industrial fields.

  15. Characterization of extended-spectrum β-lactamase (ESBL)-producing Klebsiella, Enterobacter, and Citrobacter obtained in environmental samples of a Tunisian hospital.

    Science.gov (United States)

    Dziri, Raoudha; Klibi, Naouel; Alonso, Carla Andrea; Said, Leila Ben; Bellaaj, Ridha; Slama, Karim Ben; Boudabous, Abdellatif; Torres, Carmen

    2016-10-01

    The assessment of the hospital environment as a reservoir of ESBL-producing Enterobacteriaceae in Tunisian hospitals is scarcely analyzed, except for Escherichia coli. The aim of this study was to evaluate the presence of ESBL-producing non-E. coli Enterobacteriaceae (ESBL-EbNoEc) in 300 samples of abiotic surfaces and the hands of patients and staff of a Tunisian Hospital, and to characterize the ESBL genes of the recovered isolates. ESBL-EbNoEc were recovered in 28 of 300 (9.3%) analyzed samples and were identified as Klebsiella pneumoniae (n= 11), Enterobacter cloacae (n=11), Citrobacter freundii (n=4) and Klebsiella oxytoca (n=2). The bla genes identified by PCR and sequencing among the strains were as follows: 11 K.pneumoniae strains [blaCTX-M-15+ blaTEM-1+ blaSHV-11 (n=6); blaCTX-M-15+ blaTEM-1+ blaSHV-28 (n=3); blaCTX-M-15+ blaTEM-1+ blaSHV-1 (n=2)], 11 E. cloacae strains [blaCTX-M-15 (n=6); blaCTX-M-15+ blaTEM-1b (n=2); blaCTX-M-15+ blaTEM-1b+ blaOXA-1 (n=1);blaCTX-M-15+ blaOXA-1 (n=1);blaSHV-12 (n=1)], 4 C. freundii strains [blaCTX-M-15] and 2 K. oxytoca strains [blaCTX-M-15 (n=1); blaSHV-12 (n=1)]. The ISEcp1 and orf477 sequences were identified upstream and downstream of the blaCTX-M-15 gene, respectively, in 3 K. pneumoniae and 3 E. cloacae isolates. The PFGE analysis demonstrated three unrelated pulsotypes in K. pneumoniae strains and five pulsotypes in E. cloacae. The uncontrolled dissemination of ESBL-producing bacteria, even in the hospital environment, has become a real problem and new strategies and hygienic rules are needed to stop this bacterial dissemination. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Biochemical characterization of CTX-M-15 from Enterobacter cloacae and designing a novel non-β-lactam-β-lactamase inhibitor.

    Directory of Open Access Journals (Sweden)

    Mohammad Faheem

    Full Text Available The worldwide dissemination of CTX-M type β-lactamases is a threat to human health. Previously, we have reported the spread of bla(CTX-M-15 gene in different clinical strains of Enterobacteriaceae from the hospital settings of Aligarh in north India. In view of the varying resistance pattern against cephalosporins and other β-lactam antibiotics, we intended to understand the correlation between MICs and catalytic activity of CTX-M-15. In this study, steady-state kinetic parameters and MICs were determined on E. coli DH5α transformed with bla(CTX-M-15 gene that was cloned from Enterobacter cloacae (EC-15 strain of clinical background. The effect of conventional β-lactamase inhibitors (clavulanic acid, sulbactam and tazobactam on CTX-M-15 was also studied. We have found that tazobactam is the best among these inhibitors against CTX-M-15. The inhibition characteristic of tazobactam is defined by its very low IC(50 value (6 nM, high affinity (K(i = 0.017 µM and better acylation efficiency (k(+2/K' = 0.44 µM(-1s(-1. It forms an acyl-enzyme covalent complex, which is quite stable (k(+3 = 0.0057 s(-1. Since increasing resistance has been reported against conventional β-lactam antibiotic-inhibitor combinations, we aspire to design a non-β-lactam core containing β-lactamase inhibitor. For this, we screened ZINC database and performed molecular docking to identify a potential non-β-lactam based inhibitor (ZINC03787097. The MICs of cephalosporin antibiotics in combination with this inhibitor gave promising results. Steady-state kinetics and molecular docking studies showed that ZINC03787097 is a reversible inhibitor which binds non-covalently to the active site of the enzyme through hydrogen bonds and hydrophobic interactions. Though, it's IC(50 (180 nM is much higher than tazobactam, it has good affinity for CTX-M-15 (K(i = 0.388 µM. This study concludes that ZINC03787097 compound can be used as seed molecule to design more

  17. Cloning and knockout of formate hydrogen lyase and H{sub 2}-uptake hydrogenase genes in Enterobacter aerogenes for enhanced hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Hongxin; Ma, Kun; Lu, Yuan; Zhang, Chong; Wang, Liyan; Xing, Xin-Hui [Institute of Biochemical Engineering, Department of Chemical Engineering, Tsinghua University, Tsinghua Yuan, Beijing 100084 (China)

    2009-01-15

    A 5431-bp DNA fragment partially encoding the formate hydrogen lyase (FHL) gene cluster hycABCDE was isolated and identified from Enterobacter aerogenes IAM1183 chromosomal DNA. All the five putative gene products showed a high degree of homology to the reported bacterial FHL proteins. The gene hycA, encoding the FHL repressor protein, and hybO, encoding the small subunit of the uptake hydrogenase, were targeted for genetic knockout for improving the hydrogen production. The pYM-Red recombination system was adopted to form insertional mutations in the E. aerogenes genome, thereby creating mutant strains of IAM1183-A ({delta} hycA), IAM1183-O ({delta} hybO), and IAM1183-AO ({delta} hycA/ {delta} hybO double knockout). The hydrogen production experiments with these mutants showed that the maximum specific hydrogen productivities of IAM1183-A, IAM1183-O, and IAM1183-AO were 2879.466 {+-} 38.59, 2747.203 {+-} 13.25 and 3372.019 {+-} 4.39 (ml h{sup -1} g{sup -1}dry cell weight), respectively, higher than that of the wild strain (2321.861 {+-} 15.34 ml h{sup -1} g{sup -1}dry cell weight). The total H{sub 2} yields by the three mutants IAM1183-A, IAM1183-O and IAM1183-AO were 0.73, 0.78, and 0.83 mol-H{sub 2}/mol glucose, respectively, while the wild-type IAM1183 was only 0.65 mol-H{sub 2}/mol glucose. The metabolites of the mutants including acetate, ethanol, 2,3-butanediol and succinate were all increased compared with that of the wild type, implying the changed metabolic flux by the mutation. In the fermentor cultivation with IAM1183 {delta} hycA/ {delta} hybO, the total hydrogen volume after 16 h cultivation reached 4.4 L, while that for the wild type was only 2.9 L. (author)

  18. Incidência de infecções por enterobactérias resistentes a carbapenêmicos em pacientes previamente colonizados

    Directory of Open Access Journals (Sweden)

    Paula Lüttjohann Rodrigues

    2015-09-01

    Full Text Available Introdução: Nos últimos anos, a incidência mundial de enterobactérias resistentes a carbapenêmicos (ERC tem aumentado. A disseminação de ERC é preocupante considerando as limitações terapêuticas e a alta mortalidade de infecções causadas por essas bactérias. O objetivo deste estudo foi determinar a incidência de infecções por ERC em pacientes previamente colonizados. Métodos: Estudo de coorte, retrospectivo, realizado em hospital universitário de Porto Alegre, no período de janeiro a dezembro de 2014. Foram incluídos todos os pacientes com coleta de swab retal para pesquisa de ERC. Foram considerados infectados pacientes com isolado de ERC em amostra clínica que apresentaram swab retal prévio positivo para a mesma espécie. A mortalidade bruta foi analisada em 30 dias após o isolamento de ERC. Resultados: Foram coletados 2.733 swabs retais, sendo 78 (2,85% destes positivos para ERC (pacientes colonizados. Um total de 33% (26/78 dos pacientes colonizados também apresentaram ERC em amostra clínica. O tempo médio entre o isolamento de ERC em swab (colonização e em material clínico (infecção foi de 14,9 dias (± 13,6. A maior parte das amostras clínicas positivas para ERC foi em urina (46,1%; 12/26. A mortalidade foi de 61% (16/26 nos pacientes colonizados e com infecção versus 46% (24/52 nos pacientes colonizados que não desenvolveram infecção. Conclusão: Nossos dados demonstram que 1/3 de pacientes colonizados desenvolveram infecção por ERC. Foi possível observar uma mortalidade maior em pacientes infectados em relação a pacientes apenas colonizados por ERC.

  19. Actividad inhibitoria de dihidroxifenilpropenona sobre β-lactamasa de Enterobacter cloacae: estudio preliminar en el desarrollo de fármacos para enfrentar la resistencia bacteriana

    Directory of Open Access Journals (Sweden)

    Cristina Lucía Mora

    2014-04-01

    Full Text Available Introducción. Microorganismos patógenos como Enterobacter cloacae producen enzimas β-lactamasas que les confieren resistencia a los antibioticos β-lactámicos y actualmente se ha identificado la actividad limitada de los inhibidores enzimáticos, de modo que las únicas posibilidades para enfrentar la problemática son el diseño de nuevos fármacos y el uso racional de los mismos. Objetivo. Evaluar el efecto de la chalcona dihidroxifenilpropenona sobre un aislamiento clínico de E. cloacae y sobre la enzima β-lactamasa aislada a partir de este microorganismo resistente como un aporte hacia la búsqueda de compuestos inhibidores de β-lactamasa. Materiales y métodos. Se sintetizó la chalcona dihidroxifenilpropenona y se evaluó sobre el aislamiento clínico de E. cloacae para determinar la concentración mínima inhibitoria mediante el método de microdilución en caldo y con la β-lactamasa purificada mediante cromatografía de afinidad se realizaron estudios espectrofotométricos de cinética enzimática. Resultados. La concentración mínima inhibitoria de la dihidroxifenilpropenona sobre E. cloacae fue de 35 μg/ml, el porcentaje de recuperación de la enzima β-lactamasa a partir del microorganismo fue de 31,75% y en el estudio cinético se evidenció actividad inhibitoria de acuerdo con los parámetros cinéticos de Vmax= 1,7 x 10-3 μM/min y KM´= 2330 μM. Conclusión. La chalcona dihidroxifenilpropenona ejerce su actividad inhibitoria a través de la interacción con la enzima β-lactamasa y de esta manera protege la integridad estructural de los antibióticos β-lactámicos, este efecto sinérgico lo convierte en un compuesto promisorio en la búsqueda de alternativas para enfrentar la problemática de resistencia bacteriana.

  20. Purification and Characterization of Glutaminase Free Asparaginase from Enterobacter cloacae: In-Vitro Evaluation of Cytotoxic Potential against Human Myeloid Leukemia HL-60 Cells.

    Directory of Open Access Journals (Sweden)

    Islam Husain

    Full Text Available Asparaginase is an important antileukemic agent extensively used worldwide but the intrinsic glutaminase activity of this enzymatic drug is responsible for serious life threatening side effects. Hence, glutaminase free asparaginase is much needed for upgradation of therapeutic index of asparaginase therapy. In the present study, glutaminase free asparaginase produced from Enterobacter cloacae was purified to apparent homogeneity. The purified enzyme was found to be homodimer of approximately 106 kDa with monomeric size of approximately 52 kDa and pI 4.5. Purified enzyme showed optimum activity between pH 7-8 and temperature 35-40°C, which is close to the internal environment of human body. Monovalent cations such as Na+ and K+ enhanced asparaginase activity whereas divalent and trivalent cations, Ca2+, Mg2+, Zn2+, Mn2+, and Fe3+ inhibited the enzyme activity. Kinetic parameters Km, Vmax and Kcat of purified enzyme were found to be 1.58×10-3 M, 2.22 IU μg-1 and 5.3 × 104 S-1, respectively. Purified enzyme showed prolonged in vitro serum (T1/2 = ~ 39 h and trypsin (T1/2 = ~ 32 min half life, which is therapeutically remarkable feature. The cytotoxic activity of enzyme was examined against a panel of human cancer cell lines, HL-60, MOLT-4, MDA-MB-231 and T47D, and highest cytotoxicity observed against HL-60 cells (IC50 ~ 3.1 IU ml-1, which was comparable to commercial asparaginase. Cell and nuclear morphological studies of HL-60 cells showed that on treatment with purified asparaginase symptoms of apoptosis were increased in dose dependent manner. Cell cycle progression analysis indicates that enzyme induces apoptosis by cell cycle arrest in G0/G1 phase. Mitochondrial membrane potential loss showed that enzyme also triggers the mitochondrial pathway of apoptosis. Furthermore, the enzyme was found to be nontoxic for human noncancerous cells FR-2 and nonhemolytic for human erythrocytes.

  1. Caracterización de la comunidad bacteriana aerobia en sanguijuelas (Hirudinea, Haementeria sp. (Glossiphoniidae y Oxytychus ornatus (Macrobdellidae de El Bagre, Antioquia = Characterization of the aerobic bacterial community in leeches Haementeria sp (Hirudinea: Glossiphoniidae y Oxytychus ornatus (Hirudinea: Macrobdellidae de El Bagre, Antioquia

    Directory of Open Access Journals (Sweden)

    López Isaza, Laura Patricia

    2012-01-01

    Full Text Available Se ha incrementado el uso terapéutico de las sanguijuelas y se ha demostrado que ellas pueden inocular bacterias causantes de infecciones en el 20% de los pacientes. El hallazgo en Antioquia de dos especies de sanguijuelas promisorias para hirudoterapia motivó este estudio para identificar las bacterias en la superficie, la probóscide y el intestino de estos anélidos y evaluar su sensibilidad a antibióticos. Las sanguijuelas estudiadas se identificaron como Haementeria sp., y Oxytychus ornatus. Muestras de la superficie, boca e intestino de ambos anélidos se inocularon en agar sangre, agar sangre con ampicilina y agar eosina azul de metileno. La identificación de las bacterias y su sensibilidad a antibióticos se evaluaron por el método automatizado Vitek (Biomerieux®. Se hicieron en total 26 aislamientos pertenecientes a 12 especies de nueve géneros. Enterobacter cloacae fue la especie más frecuente en ambos anélidos. Las bacterias fueron sensibles a los antibióticos comúnmente empleados en las infecciones causadas por este tipo de microorganismos. Se sugiere hacer profilaxis con antibióticos en los pacientes que reciban terapia con los anélidos investigados e implementar los protocolos estandarizados para el lavado de los animales antes de su uso y para el aseo de los acuarios en donde se los mantenga.

  2. Sp6 and Sp8 Transcription Factors Control AER Formation and Dorsal-Ventral Patterning in Limb Development

    Science.gov (United States)

    Haro, Endika; Delgado, Irene; Junco, Marisa; Yamada, Yoshihiko; Mansouri, Ahmed; Oberg, Kerby C.; Ros, Marian A.

    2014-01-01

    The formation and maintenance of the apical ectodermal ridge (AER) is critical for the outgrowth and patterning of the vertebrate limb. The induction of the AER is a complex process that relies on integrated interactions among the Fgf, Wnt, and Bmp signaling pathways that operate within the ectoderm and between the ectoderm and the mesoderm of the early limb bud. The transcription factors Sp6 and Sp8 are expressed in the limb ectoderm and AER during limb development. Sp6 mutant mice display a mild syndactyly phenotype while Sp8 mutants exhibit severe limb truncations. Both mutants show defects in AER maturation and in dorsal-ventral patterning. To gain further insights into the role Sp6 and Sp8 play in limb development, we have produced mice lacking both Sp6 and Sp8 activity in the limb ectoderm. Remarkably, the elimination or significant reduction in Sp6;Sp8 gene dosage leads to tetra-amelia; initial budding occurs, but neither Fgf8 nor En1 are activated. Mutants bearing a single functional allele of Sp8 (Sp6−/−;Sp8+/−) exhibit a split-hand/foot malformation phenotype with double dorsal digit tips probably due to an irregular and immature AER that is not maintained in the center of the bud and on the abnormal expansion of Wnt7a expression to the ventral ectoderm. Our data are compatible with Sp6 and Sp8 working together and in a dose-dependent manner as indispensable mediators of Wnt/βcatenin and Bmp signaling in the limb ectoderm. We suggest that the function of these factors links proximal-distal and dorsal-ventral patterning. PMID:25166858

  3. Analysis list: SP2 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available SP2 Blood,Liver,Pluripotent stem cell + hg19 http://dbarchive.biosciencedbc.jp/kyus...hu-u/hg19/target/SP2.1.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/target/SP2.5.tsv http://dbarchive....biosciencedbc.jp/kyushu-u/hg19/target/SP2.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/colo/SP2.Blood.tsv,http:...//dbarchive.biosciencedbc.jp/kyushu-u/hg19/colo/SP2.Liver.tsv,http:...//dbarchive.biosciencedbc.jp/kyushu-u/hg19/colo/SP2.Pluripotent_stem_cell.tsv http://dbarchive.biosciencedbc

  4. Biodegradation of resorcinol byPseudomonas sp.

    Institute of Scientific and Technical Information of China (English)

    Nader Hajizadeh; Najibeh Shirzad; Ali Farzi; Mojtaba Salouti; Azra Momeni

    2016-01-01

    ABSTRACT Objective:To investigate the ability ofPseudomonas sp. isolated from East Azarbaijan, Iran in bioremediation of resorcinol. Methods: Resorcinol biodegradation was evaluated using spectrophotometry and confirmed by gas chromatography-mass spectroscopy. Results:This isolate was able to remove up to 37.12% of resorcinol from contaminated water. Reusability experiments had confirmed the biodegradation process which produced seven intermediate compounds. These intermediates were characterized by gas chromatography-mass spectroscopy technique. The products of resorcinol biodegradation were apparently 1, 4-cyclohexadiene, nonadecene, 2-heptadecanone, 1-isopropyl-2-methoxy-4-methylbenzene, hexadecanoic acid, 9-octadecenoic acid, phenol and 5-methyl-2-(1-methylethyl). Conclusions: The findings revealed thatPseudomonas sp. is able to degrade resorcinol. Because of being an indigenous organism, this isolate is more compatible with the climate of the northwest region of Iran and possibly will be used for degradation of other similar aromatic compounds.

  5. SP-100 space reactor power system readiness

    International Nuclear Information System (INIS)

    Josloff, A.T.; Matteo, D.N.; Bailey, H.S.

    1992-01-01

    This paper discusses the SP-100 Space Reactor Power System which is being developed by GE, under contract to the U.S. Department of Energy, to provide electrical power in the range of 10's to 100's of kW. The system represents an enabling technology for a wide variety of earth orbital and interplanetary science missions, nuclear electric propulsion (NEP) stages, and lunar/Mars surface power for the Space Exploration Initiative (SEI). The technology and design is now at a state of readiness to support the definition of early flight demonstration missions. Of particular importance is that SP-100 meets the demanding U.S. safety performance, reliability and life requirements. The system is scalable and flexible and can be configured to provide 10's to 100's of kWe without repeating development work and can meet DoD goals for an early, low-power demonstration flight in the 1996-1997 time frame

  6. Superfield quantization in Sp(2) covariant formalism

    CERN Document Server

    Lavrov, P M

    2001-01-01

    The rules of the superfield Sp(2) covariant quantization of the arbitrary gauge theories for the case of the introduction of the gauging with the derivative equations for the gauge functional are generalized. The possibilities of realization of the expanded anti-brackets are considered and it is shown, that only one of the realizations is compatible with the transformations of the expanded BRST-symmetry in the form of super translations along the Grassmann superspace coordinates

  7. Spøgelsets egne ord

    DEFF Research Database (Denmark)

    Gemzøe, Anker

    2012-01-01

    refleksioner over den gengangerscene, der åbner Shakespeares Hamlet. Ifølge Derridas ’hantologie’ opererer spøgelser i en eksistentiel tidslighed, der har at gøre med sorg, sprog og forvandling. Genremæssigt, tilføjer Gemzøe, har gengangeren det med at husere i tragedien. Med Derridas ’hantologie’ som en af de...

  8. Carbon sp chains in graphene nanoholes

    International Nuclear Information System (INIS)

    Castelli, Ivano E; Ferri, Nicola; Onida, Giovanni; Manini, Nicola

    2012-01-01

    Nowadays sp carbon chains terminated by graphene or graphitic-like carbon are synthesized routinely in several nanotech labs. We propose an ab initio study of such carbon-only materials, by computing their structure and stability, as well as their electronic, vibrational and magnetic properties. We adopt a fair compromise of microscopic realism with a certain level of idealization in the model configurations, and predict a number of properties susceptible to comparison with experiment. (paper)

  9. Carbon sp chains in graphene nanoholes

    Science.gov (United States)

    Castelli, Ivano E.; Ferri, Nicola; Onida, Giovanni; Manini, Nicola

    2012-03-01

    Nowadays sp carbon chains terminated by graphene or graphitic-like carbon are synthesized routinely in several nanotech labs. We propose an ab initio study of such carbon-only materials, by computing their structure and stability, as well as their electronic, vibrational and magnetic properties. We adopt a fair compromise of microscopic realism with a certain level of idealization in the model configurations, and predict a number of properties susceptible to comparison with experiment.

  10. Commercial technologies from the SP-100 program

    International Nuclear Information System (INIS)

    Truscello, V.C.; Fujita, T.; Mondt, J.F.

    1995-01-01

    For more than a decade, Jet Propulsion Labortory and Los Alamos have managed a multi-agency funded effort to develop a space reactor power system. This SP-100 Program has developed technologies required for space power systems that can be implemented in the industrial and commercial sectors to improve competitiveness in the global economy. Initial steps taken to transfer this technology from the laboratories to industrial and commercial entities within United States include: (1) identifying specific technologies having commercial potential; (2) distributing information describing the identified technologies and interacting with interested commercial and industrial entities to develop application-specific details and requirements; and (3) providing a technological data base that leads to transfer of technology or the forming of teaming arrangements to accomplish the transfer by tailoring the technology to meet application-specific requirements. SP-100 technologies having commercial potential encompass fabrication processes, devices, and components. Examples: a process for bonding refractory metals to graphite, a device to sense the position of an actuator and a component to enable rotating machines to operate without supplying lubrication (self-lubricating ball bearing). Shortly after the NASA Regional Technology Transfer Centers widely disseminated information covering SP-100 technologies, over one hundred expressions of interest were received, which indicate that there is a large potential benefit in transferring SP-100 technology. Interactions with industrial and commercial entities have identified a substantial need for creating teaming arrangements involving the interested entity and personnel from laboratories and their contractors, who have the knowledge and ability to tailor the technology to meet application-specific requirements. copyright 1995 American Institute of Physics

  11. Thermomucor abortosporangium sp. nov. (Fungi: Mucorales

    Directory of Open Access Journals (Sweden)

    A. Swathi Sri

    2012-03-01

    Full Text Available Thermomucor abortosporangium A. Swathi Sri & A. Subrahm., sp. nov. is described as the second species of Thermomucor. It differs from the type species of T. indicae-seudaticae in the branching pattern of sporangiophores, size and shape of sporangiospores and production of abortosporangia. Zygospores are reddish brown, globose, psilate, isogamic and formed at low (37°C temperature whilst the higher temperatures are prohibitive. The fungus grows well at 50°C on PDA, SMA and MEA.

  12. Optimization of cellulase production by Penicillium sp.

    Science.gov (United States)

    Prasanna, H N; Ramanjaneyulu, G; Rajasekhar Reddy, B

    2016-12-01

    The production of cellulolytic enzymes (β-exoglucanase, β-endoglucanase and β-glucosidase) by Penicillium sp. on three different media in liquid shake culture conditions was compared. The organism exhibited relatively highest activity of endoglucanase among three enzymes measured at 7-day interval during the course of its growth on Czapek-Dox medium supplemented with 0.5 % (w/v) cellulose. Cellulose at 0.5 %, lactose at 0.5 %, sawdust at 0.5 %, yeast extract at 0.2 % as a nitrogen source, pH 5.0 and 30 °C temperature were found to be optimal for growth and cellulase production by Penicillium sp. Yields of Fpase, CMCase and β-glucosidase, attained on optimized medium with Penicillium sp. were 8.7, 25 and 9.52 U/ml, respectively with increment of 9.2, 5.9 and 43.8-folds over titers of the respective enzyme on unoptimised medium. Cellulase of the fungal culture with the ratio of β-glucosidase to Fpase greater than one will hold potential for biotechnological applications.

  13. Biosorption of 241Am by Candida sp

    International Nuclear Information System (INIS)

    Luo Shunzhong; Zhang Taiming; Liu Ning; Yang Yuanyou; Jin Jiannan; Hua Xinfeng

    2003-01-01

    The biosorption of radionuclide 241 Am from solutions by Candida sp., and the influences of experimental conditions on the adsorption were studied. The results showed that the adsorption equilibrium was achieved within 4h and the optimum pH=2. No significant differences on 241 Am biosorption were observed at 10-45 degree C, or challenged with Au 3+ or Ag + , even 1500 times or 4500 times over 241 Am, respectively. The adsorption rate could reach 97.8% by dry Candida sp. of 0.82 g/L in 241 Am solutions (pH=2) of 5.6-111 MBq/L (44.04-873.0 μg/L) (C 0 ), with maximum adsorption capacity (W) of 63.5 MBq/g (501.8 μg/g), implying that the removal of 241 Am by Candida sp. from solutions was feasible. The relationship between activities (C 0 ) and adsorption capacities (W) of 241 Am indicated that the biosorption process could be described by Langmuir adsorption isotherm

  14. Biosorption of americium-241 by Candida sp

    International Nuclear Information System (INIS)

    Luo Shunzhong; Zhang Taiming; Liu Ning; Yang Yuanyou; Jin Jiannan; Liao Jiali

    2003-01-01

    As an important radioisotope in nuclear industry and other fields, americium-241 is one of the most serious contamination concerns duo to its high toxicity and long half-life. In this experiment, the biosorption of 241 Am from solution by Candida sp., and the effects of various experimental conditions on the adsorption were investigated. The preliminary results showed that the adsorption of 241 Am by Candida sp. was efficient. 241 Am could be removed by Candida sp. of 0.82 g/L (dry weight) from 241 Am solutions of 5.6-111 MBq/L (44.3-877.2 μg/L)(C 0 ), with maximum adsorption rate (R) of 98% and maximum adsorption capacities (W) of 63.5 MBq/g biomass (dry weight) (501.8 μg/g). The biosorption equilibrium was achieved within 4 hour and the optimum pH was pH = 2. No significant differences on 241 Am adsorption were observed at 10 C-45 C, or in solutions containing Au 3+ or Ag + , even 1500 times or 4500 times above the 241 Am concentration, respectively. The relationship between concentrations and adsorption capacities of 241 Am indicated the biosorption process should be described by a Langmuir adsorption isotherm. (orig.)

  15. Borrelia bissettiae sp. nov. and Borrelia californiensis sp. nov. prevail in diverse enzootic transmission cycles.

    Science.gov (United States)

    Margos, Gabriele; Lane, Robert S; Fedorova, Natalia; Koloczek, Johannes; Piesman, Joseph; Hojgaard, Andrias; Sing, Andreas; Fingerle, Volker

    2016-03-01

    Two species of the genus Borrelia , Borrelia bissettiae sp. nov. and Borrelia californiensis sp. nov., were first described by Postic and co-workers on the basis of genetic analyses of several loci. Multilocus sequence analysis of eight housekeeping loci confirmed that these two Borrelia genomospecies are distinct members of the Borrelia burgdorferi sensu lato complex. B. bissettiae sp. nov. was initially described in transmission cycles involving Neotoma fuscipes wood rats and Ixodes pacificus ticks in California, and Neotoma mexicana and Ixodes spinipalpis in Colorado. The preferred host of B. californiensis sp. nov. appears to be the California kangaroo rat, Dipodomys californicus ; Ixodes jellisoni , I. spinipalipis and I. pacificus ticks are naturally infected with it. Thus, the ecological associations of the two genomospecies and their genetic distance from all other known Borrelia genomospecies species justify their description as separate genomospecies: B. bissettiae sp. nov. (type strain DN127 T  = DSM 17990 T  =  CIP 109136 T ) and B. californiensis (type strain CA446 T  = DSM 17989 T  = ATCC BAA-2689 T ).

  16. EFEKTIFITAS DAYA HAMBAT BAKTERI Streptomyces sp TERHADAP Erwinia sp PENYEBAB PENYAKIT BUSUK REBAH PADA TANAMAN LIDAH BUAYA (Aloe barbadensis Mill

    Directory of Open Access Journals (Sweden)

    SARMILA TASNIM

    2013-05-01

    Full Text Available Streptomyces sp was conducted from December 2010 - June 2011 at the Laboratoryof Microbiology, Biology Department, Math and Science Faculty, UdayanaUniversity Bukit Jimbaran-Bali. Implementation stages of the research consisted ofisolation and testing of the antibiotic activity Streptomyces sp to inhibit growthbacterial pathogens Erwinia sp as a cause of disease in plants fallen foul (Soft rot ofAloe barbadensis Mill.The results of this study have eight isolates of Streptomyces spwith macroscopic and microscopic characters are varied. Furthermore, all isolateswere obtained and then tested against antibiotic activity to inhibit growth the bacteriaErwinia sp. Test results obtained by Streptomyces sp that has the most effective ininhibiting the ability of the bacteria Erwinia sp isolates are Streptomyces sp2for (45%.

  17. Nanoscale transformation of sp2 to sp3 of graphite by slow highly charged ion irradiation

    International Nuclear Information System (INIS)

    Meguro, T.; Hida, A.; Koguchi, Y.; Miyamoto, S.; Yamamoto, Y.; Takai, H.; Maeda, K.; Aoyagi, Y.

    2003-01-01

    Nanoscale transformation of electronic states by highly charged ion (HCI) impact on graphite surfaces is described. The high potential energy of slow HCI, which induces multiple emission of electrons from the surface, provides a strong modification of the electronic states of the local area upon graphite surfaces. The HCI impact and the subsequent surface treatment either by electron injection from a scanning tunneling microscopy tip or by He-Cd laser irradiation induce a localized transition from sp 2 to sp 3 hybridization in graphite, resulting in the formation of nanoscale diamond-like structures (nanodiamond) at the impact region. From Raman spectroscopic measurements on sp 2 related peaks, it is found that the HCI irradiation creates vacancy complexes in contrast to ions having a lower charge state, which generate single vacancies. It is of interest that a single impact of HCI creates one nanodiamond structure, suggesting potential applications of HCI in nanoscale material processing

  18. Burkholderia humisilvae sp. nov., Burkholderia solisilvae sp. nov. and Burkholderia rhizosphaerae sp. nov., isolated from forest soil and rhizosphere soil.

    Science.gov (United States)

    Lee, Jae-Chan; Whang, Kyung-Sook

    2015-09-01

    Strains Y-12(T) and Y-47(T) were isolated from mountain forest soil and strain WR43(T) was isolated from rhizosphere soil, at Daejeon, Korea. The three strains grew at 10-55 °C (optimal growth at 28-30 °C), at pH 3.0-8.0 (optimal growth at pH 6.0) and in the presence of 0-4.0% (w/v) NaCl, growing optimally in the absence of added NaCl. On the basis of 16S rRNA gene sequence analysis, the three strains were found to belong to the genus Burkholderia, showing the closest phylogenetic similarity to Burkholderia diazotrophica JPY461(T) (97.2-97.7%); the similarity between the three sequences ranged from 98.3 to 98.7%. Additionally, the three strains formed a distinct group in phylogenetic trees based on the housekeeping genes recA and gyrB. The predominant ubiquinone was Q-8, the major fatty acids were C16 : 0 and C17  : 0 cyclo and the DNA G+C content of the novel isolates was 61.6-64.4 mol%. DNA-DNA relatedness among the three strains and the type strains of the closest species of the genus Burkholderia was less than 50%. On the basis of 16S rRNA, recA and gyrB gene sequence similarities, chemotaxonomic and phenotypic data, the three strains represent three novel species within the genus Burkholderia, for which the names Burkholderia humisilvae sp. nov. (type strain Y-12(T)= KACC 17601(T) = NBRC 109933(T) = NCAIM B 02543(T)), Burkholderia solisilvae sp. nov. (type strain Y-47(T) = KACC 17602(T)= NBRC 109934(T) = NCAIM B 02539(T)) and Burkholderia rhizosphaerae sp. nov. (type strain WR43(T) = KACC 17603(T) = NBRC 109935(T) = NCAIM B 02541(T)) are proposed.

  19. Bifidobacterium reuteri sp. nov., Bifidobacterium callitrichos sp. nov., Bifidobacterium saguini sp. nov., Bifidobacterium stellenboschense sp. nov. and Bifidobacterium biavatii sp. nov. isolated from faeces of common marmoset (Callithrix jacchus) and red-handed tamarin (Saguinus midas).

    Science.gov (United States)

    Endo, Akihito; Futagawa-Endo, Yuka; Schumann, Peter; Pukall, Rüdiger; Dicks, Leon M T

    2012-03-01

    Five strains of bifidobacteria were isolated from faeces of a common marmoset (Callithrix jacchus) and a red-handed tamarin (Saguinus midas). The five isolates clustered inside the phylogenetic group of the genus Bifidobacterium but did not show high sequence similarities between the isolates and to known species in the genus by phylogenetic analysis based on 16S rRNA gene sequences. Sequence analyses of dnaJ1 and hsp60 also indicated their independent phylogenetic positions to each other in the Bifidobacterium cluster. DNA G+C contents of the species ranged from 57.3 to 66.3 mol%, which is within the values recorded for Bifidobacterium species. All isolates showed fructose-6-phosphate phosphoketolase activity. Based on the data provided, the five isolates represent five novel species, for which the names Bifidobacterium reuteri sp. nov. (type strain: AFB22-1(T) = JCM 17295(T) = DSM 23975(T)), Bifidobacterium callitrichos sp. nov. (type strain: AFB22-5(T) = JCM 17296(T) = DSM 23973(T)), Bifidobacterium saguini sp. nov. (type strain: AFB23-1(T) = JCM 17297(T) = DSM 23967(T)), Bifidobacterium stellenboschense sp. nov. (type strain: AFB23-3(T) = JCM 17298(T) = DSM 23968(T)) and Bifidobacterium biavatii sp. nov. (type strain: AFB23-4(T) = JCM 17299(T) = DSM 23969(T)) are proposed. Copyright © 2011 Elsevier GmbH. All rights reserved.

  20. Fermentation of Azolla sp. leaves and the utilization as a feed ingredient of tilapia Oreochromis sp.

    Directory of Open Access Journals (Sweden)

    Nur Bambang Priyo Utomo

    2015-03-01

    Full Text Available ABSTRACTThe objective of this study was to study the effect of incubation period on the nutritional content of Azolla sp. meal fermented by Trichoderma harzianum, and its optimum supplementation level in the feed of tilapia Oreochromis sp. In incubation period treatments, fermentation of Azolla meal was performed in two, six, eight, and ten days (AF2, AF6, AF8, AF10 using Trichoderma harzianum as the fermentor. The fish used in this study was tilapia Oreochromis sp. with an average weight of 10.59±1.29 g. The design of the feeding treatments was repeletting commercial feed with Azolla leaves by with different supplementation levels, i.e. 0% (A/control, 30% (B, 60% (C, and 90% (D. Faecal collection for digestibility measurement was conducted for 15 days and fish growth rate was observed for 40 days. Azolla meal fermented for two days (AF2 showed the best results among the other treatments with a crude fiber decrease of 37.19% and protein increase of 38.65%. The results of this study indicate that fermentation can increase the nutritional quality of Azolla meal and its most optimal supplementation level in the diet of tilapia is 30%.Keywords: crude fiber, Azolla sp., tilapiaABSTRAKPenelitian ini bertujuan untuk mengetahui pengaruh lama waktu fermentasi daun mata lele Azolla sp. menggunakan kapang Trichoderma harzianum serta dosis optimal dalam pakan ikan nila Oreochromis sp. Proses fermentasi tepung daun mata lele dilakukan selama dua, enam, delapan, dan sepuluh hari (AF2, AF6, AF8, AF10. Ikan uji pada penelitian ini menggunakan ikan nila Oreochromis sp. dengan bobot rata-rata 10,59±1,29 g yang ditebar sebanyak 6 ekor/akuarium berukuran 50×45×30 cm3. Sebagai pakan perlakuan yakni repeletting daun mata lele dengan pakan komersil pada tingkat suplementasi 0% (A/kontrol, 30% (B, 60% (C, dan 90% (D. Pemeliharaan ikan uji dan pengumpulan data dilakukan dengan mengumpulkan feses ikan untuk uji ketercernaan selama 15 hari dan mengamati pertumbuhan

  1. Isolation of C11 Cyclopentenones from Two Didemnid Species, Lissoclinum sp. and Diplosoma sp.

    Directory of Open Access Journals (Sweden)

    Katsuhiro Ueda

    2009-12-01

    Full Text Available A series of new C11 cyclopentenones 1-7 was isolated, together with four known metabolites 9/10, 12 and 13, from the extract of the didemnid ascidian Lissoclinum sp. The other didemnid ascidian Diplosoma sp. contained didemnenones 1, 2 and 5, and five known metabolites 8-12. The structures of 1-7 were elucidated by spectroscopic analyses. Cytotoxicity of the isolated compounds was evaluated against three human cancer cell lines (HCT116, A431 and A549.

  2. Role of surfactant protein A (SP-A)/lipid interactions for SP-A functions in the lung.

    Science.gov (United States)

    Casals, C

    2001-01-01

    Surfactant protein A (SP-A), an oligomeric glycoprotein, is a member of a group of proteins named collectins that contain collagen-like and Ca(2+)-dependent carbohydrate recognition domains. SP-A interacts with a broad range of amphipathic lipids (glycerophospholipids, sphingophospholipids, glycosphingolipids, lipid A, and lipoglycans) that are present in surfactant or microbial membranes. This review summarizes SP-A/lipid interaction studies regarding the lipid system used (i.e., phospholipid vesicles, phospholipid monolayers, and lipids immobilized on silica or adsorbed on a solid support). The effect of calcium, ionic strength, and pH on the binding of SP-A to lipids and the subsequent lipid aggregation process is discussed. Current evidence suggests that hydrophobic-binding forces are involved in the peripherical association of SP-A to membranes. It is also proposed that fluid and liquid-ordered phase coexistence in surfactant membranes might favor partition of SP-A into those membranes. The binding of SP-A to surfactant membranes containing hydrophobic surfactant peptides makes possible the formation of a membrane reservoir in the alveolar fluid that is protected by SP-A against inactivation and improves the rate of surfactant film formation. In addition, the interaction of SP-A with membranes might enhance the affinity of SP-A for terminal carbohydrates of glycolipids or glycoproteins on the surface of invading microorganisms.

  3. Fresh Water Cyanobacteria Geitlerinema sp. CCC728 and Arthrospira sp. CCC729 as an Anticancer Drug Resource.

    Directory of Open Access Journals (Sweden)

    Akanksha Srivastava

    Full Text Available An increasing number of cancer patients worldwide, especially in third world countries, have raised concern to explore natural drug resources, such as the less explored fresh water filamentous cyanobacteria. Six strains of cyanobacteria (Phormidium sp. CCC727, Geitlerinema sp. CCC728, Arthrospira sp. CCC729, Phormidium sp. CCC731, Phormidium sp. CCC730, and Leptolyngbya sp. CCC732 were isolated (paddy fields and ponds in the Banaras Hindu University, campus and five strains screened for anticancer potential using human colon adenocarcinoma (HT29 and human kidney adenocarcinoma (A498 cancer cell lines. Geitlerinema sp. CCC728 and Arthrospira sp. CCC729 were the most potent as determined by examination of morphological features and by inhibition of growth by graded concentrations of crude extracts and thin-layer chromatography (TLC eluates. Cell cycle analysis and multiplex assays using cancer biomarkers also confirmed Geitlerinema sp. CCC728 and Arthrospira sp. CCC729 as cancer drug resources. Apoptotic studies in the cells of A498 (cancer and MCF-10A (normal human epithelial exposed to crude extracts and TLC fractions revealed no significant impact on MCF-10A cells emphasizing its importance in the development of anticancer drug. Identification of biomolecules from these extracts are in progress.

  4. Fresh Water Cyanobacteria Geitlerinema sp. CCC728 and Arthrospira sp. CCC729 as an Anticancer Drug Resource.

    Science.gov (United States)

    Srivastava, Akanksha; Tiwari, Ratnakar; Srivastava, Vikas; Singh, Tej Bali; Asthana, Ravi Kumar

    2015-01-01

    An increasing number of cancer patients worldwide, especially in third world countries, have raised concern to explore natural drug resources, such as the less explored fresh water filamentous cyanobacteria. Six strains of cyanobacteria (Phormidium sp. CCC727, Geitlerinema sp. CCC728, Arthrospira sp. CCC729, Phormidium sp. CCC731, Phormidium sp. CCC730, and Leptolyngbya sp. CCC732) were isolated (paddy fields and ponds in the Banaras Hindu University, campus) and five strains screened for anticancer potential using human colon adenocarcinoma (HT29) and human kidney adenocarcinoma (A498) cancer cell lines. Geitlerinema sp. CCC728 and Arthrospira sp. CCC729 were the most potent as determined by examination of morphological features and by inhibition of growth by graded concentrations of crude extracts and thin-layer chromatography (TLC) eluates. Cell cycle analysis and multiplex assays using cancer biomarkers also confirmed Geitlerinema sp. CCC728 and Arthrospira sp. CCC729 as cancer drug resources. Apoptotic studies in the cells of A498 (cancer) and MCF-10A (normal human epithelial) exposed to crude extracts and TLC fractions revealed no significant impact on MCF-10A cells emphasizing its importance in the development of anticancer drug. Identification of biomolecules from these extracts are in progress.

  5. Dominancy of Trichodesmium sp. in the Biawak Island

    Science.gov (United States)

    Prihadi, D. J.

    2018-03-01

    The Biawak Island is one of the small islands in West Java Province with an abundance of marine biological resources. This research was conducted to collect the primary producer zooplankton and water quality parameters. Direct observation is done by field surveys and measurement in situ for plankton and environmental parameters such as temperature, water transparency, water current, salinity, dissolved oxygen, and pH. Trichodesmium sp. was found dominance in where some other types of zooplankton were found in the area, like Scenedesmus sp., Sagitta sp., Acartia sp. also occurred. Further, the most abundance of Trichodesmium sp. was found in southern of Biawak Island where mangroves, coral and seagrass ecosystem provide nutrients which indirectly support the abundance of planktons. Trichodesmium sp. is plankton that can survive in water with minimum nutrient.

  6. Green Decision Making: Sustainable Transport and Systemic Planning (SP)

    DEFF Research Database (Denmark)

    Leleur, Steen

    and infrastructure assessment and on the methodology and process of systemic planning (SP). SP theory development has interchanged with practical application and testing of the SP approach in a large number of cases. The word systemic in SP indicates that complex planning problems and provision of decision support...... in today’s strategic planning needs a focus on what may be addressed as systemic insights in balance with more conventional, systematically-based findings where causal linkages can be modelled and made use of. In practice this means that SP is based on a study-specific combination of hard (quantitative......) and soft (qualitative) operations research (OR) methods; especially the latter have a function as regards knowledge generation that relates to obtaining systemic insights. Furthermore, SP applies a process that drives group-based learning forward. The group should be formed with the different stakeholder...

  7. The SP Theory of Intelligence: An Overview

    Directory of Open Access Journals (Sweden)

    J Gerard Wolff

    2013-08-01

    Full Text Available This article is an overview of the SP theory of intelligence, which aims to simplify and integrate concepts across artificial intelligence, mainstream computing and human perception and cognition, with information compression as a unifying theme. It is conceived of as a brain-like system that receives "New" information and stores some or all of it in compressed form as "Old" information; and it is realised in the form of a computer model, a first version of the SP machine. The matching and unification of patterns and the concept of multiple alignment are central ideas. Using heuristic techniques, the system builds multiple alignments that are "good" in terms of information compression. For each multiple alignment, probabilities may be calculated for associated inferences. Unsupervised learning is done by deriving new structures from partial matches between patterns and via heuristic search for sets of structures that are "good" in terms of information compression. These are normally ones that people judge to be "natural", in accordance with the "DONSVIC" principle—the discovery of natural structures via information compression. The SP theory provides an interpretation for concepts and phenomena in several other areas, including "computing", aspects of mathematics and logic, the representation of knowledge, natural language processing, pattern recognition, several kinds of reasoning, information storage and retrieval, planning and problem solving, information compression, neuroscience and human perception and cognition. Examples include the parsing and production of language with discontinuous dependencies in syntax, pattern recognition at multiple levels of abstraction and its integration with part-whole relations, nonmonotonic reasoning and reasoning with default values, reasoning in Bayesian networks, including "explaining away", causal diagnosis, and the solving of a geometric analogy problem.

  8. Methyl (Sp-2-(diphenylphosphinoferrocene-1-carboxylate

    Directory of Open Access Journals (Sweden)

    Petr Štěpnička

    2009-10-01

    Full Text Available The title compound, [Fe(C5H5(C19H16O2P], obtained serendipitously during recrystallization of 1-hydroxybenzotriazolyl (Sp-2-(diphenylphosphinoferrocene-1-carboxylate from methanol, crystallizes in the chiral space group P212121. Its crystal structure not only confirms the anticipated absolute configuration but also establishes a rather regular geometry for the ferrocene unit, devoid of any significant deformation due to the attached substituents. In the crystal, symmetry-related molecules are linked via weak C—H...O interactions.

  9. Increasing rice plant growth by Trichoderma sp.

    Science.gov (United States)

    Doni, Febri; Isahak, Anizan; Zain, Che Radziah Che Mohd; Sulaiman, Norela; Fathurahman, F.; Zain, Wan Nur Syazana Wan Mohd.; Kadhimi, Ahsan A.; Alhasnawi, Arshad Naji; Anhar, Azwir; Yusoff, Wan Mohtar Wan

    2016-11-01

    Trichoderma sp. is a plant growth promoting fungi in many crops. Initial observation on the ability to enhance rice germination and vigor have been reported. In this study, the effectiveness of a local isolate Trichoderma asprellum SL2 to enhance rice seedling growth was assessed experimentally under greenhouse condition using a completely randomized design. Results showed that inoculation of rice plants with Trichoderma asprellum SL2 significantly increase rice plants height, root length, wet weight, leaf number and biomass compared to untreated rice plants (control). The result of this study can serve as a reference for further work on the application of beneficial microorganisms to enhance rice production.

  10. SP-100 radiator design trade study

    International Nuclear Information System (INIS)

    Ewell, R.

    1992-01-01

    This paper reports on a design trade study of the SP-100 heat rejection subsystem (HRSS) which was made. A system code was used to evaluate the sensitivity of the HRSS mass and performance to changes. Variations in heat pipe diameter and cross-section, fin length and thickness, armor thickness, and overall configuration and materials were evaluated. The analysis indicates that the minimum system mass occurs for the case with many small diameter heat pipes, with ducting that maximizes the fraction of the heat pipe evaporator perimeter in contract with it

  11. Prepare for an SpR interview.

    Science.gov (United States)

    Garner, J P; Heppell, P S J

    2003-03-01

    By the time you attend an interview for a military SpR number you should have no real problems but it pays to be prepared. Begin preparations early, reading widely and talk to as many people as possible. Your consultants will have a useful viewpoint on the proceedings and may be able to help you refine your answers to the common questions. Arrive at your interview in a smart and timely fashion and answer questions with confidence and common sense. Avoid confrontation and bluff and be courteous at all times, whatever you may be feeling inside and thank the interview panel as you leave.

  12. Amino Alcohols from the Ascidian Pseudodistoma sp.

    Directory of Open Access Journals (Sweden)

    Tae Hyung Won

    2014-06-01

    Full Text Available Seven new amino alcohol compounds, pseudoaminols A–G (1–7, were isolated from the ascidian Pseudodistoma sp. collected off the coast of Chuja-do, Korea. Structures of these new compounds were determined by analysis of the spectroscopic data and from chemical conversion. The presence of an N-carboxymethyl group in two of the new compounds (6 and 7 is unprecedented among amino alcohols. Several of these compounds exhibited moderate antimicrobial activity and cytotoxicity, as well as weak inhibitory activity toward Na+/K+-ATPase.

  13. PRODUCTION OF FIBRINOLYTIC ENZYME (NATTOKINASE) FROM BACILLUS SP.

    OpenAIRE

    Padma Singh, Rekha Negi*, Vani Sharma, Alka Rani, Pallavi and Richa Prasad

    2018-01-01

    During present study Nattokinase which is a novel fibrinolytic enzyme was produced by Bacillus sp. To screen and extract nattokinase enzyme from Bacillus sp. were isolated from soil of different agricultural field by serial dilution method. Out of 10 isolate, one strain i.e. B3 produced nattokinase on screening medium. B3 was identified by biochemical characterization. The caseinolytic activity of Nattokinase was 0.526 U/ml and the selected isolate Bacillus sp. could produce active nattokinas...

  14. Indirect Manganese Removal by Stenotrophomonas sp. and Lysinibacillus sp. Isolated from Brazilian Mine Water

    Directory of Open Access Journals (Sweden)

    Natália Rocha Barboza

    2015-01-01

    Full Text Available Manganese is a contaminant in the wastewaters produced by Brazilian mining operations, and the removal of the metal is notoriously difficult because of the high stability of the Mn(II ion in aqueous solutions. To explore a biological approach for removing excessive amounts of aqueous Mn(II, we investigated the potential of Mn(II oxidation by both consortium and bacterial isolates from a Brazilian manganese mine. A bacterial consortium was able to remove 99.7% of the Mn(II. A phylogenetic analysis of isolates demonstrated that the predominant microorganisms were members of Stenotrophomonas, Bacillus, and Lysinibacillus genera. Mn(II removal rates between 58.5% and 70.9% were observed for Bacillus sp. and Stenotrophomonas sp. while the Lysinibacillus isolate 13P removes 82.7%. The catalytic oxidation of Mn(II mediated by multicopper oxidase was not properly detected; however, in all of the experiments, a significant increase in the pH of the culture medium was detected. No aggregates inside the cells grown for a week were found by electronic microscopy. Nevertheless, an energy-dispersive X-ray spectroscopy of the isolates revealed the presence of manganese in Stenotrophomonas sp. and Lysinibacillus sp. grown in K medium. These results suggest that members of Stenotrophomonas and Lysinibacillus genera were able to remove Mn(II by a nonenzymatic pathway.

  15. Screening of biodiesel production from waste tuna oil (Thunnus sp.), seaweed Kappaphycus alvarezii and Gracilaria sp.

    Science.gov (United States)

    Alamsjah, Mochammad Amin; Abdillah, Annur Ahadi; Mustikawati, Hutami; Atari, Suci Dwi Purnawa

    2017-09-01

    Biodiesel has several advantages over solar. Compared to solar, biodiesel has more eco-friendly characteristic and produces lower greenhouse gas emissions. Biodiesel that is made from animal fats can be produced from fish oil, while other alternative sources from vegetable oils are seaweed Kappaphycus alvarezii and Gracilaria sp. Waste tuna oil (Thunnus sp.) in Indonesia is commonly a side product of tuna canning industries known as tuna precook oil; on the other hand, seaweed Gracilaria sp. and Kappaphycus alvarezii are commonly found in Indonesia's seas. Seaweed waste that was used in the present study was 100 kg and in wet condition, and the waste oil was 10 liter. The seaweed was extracted with soxhletation method that used n-hexane as the solvent. To produce biodiesel, trans esterification was performed on the seaweed oil that was obtained from the soxhletation process and waste tuna oil. Biodiesel manufactured from seaweed K. alvarezii obtained the best score in flash point, freezing point, and viscosity test. However, according to level of manufacturing efficiency, biodiesel from waste tuna oil is more efficient and relatively easier compared to biodiesel from waste K. alvarezii and Gracilaria sp.

  16. Biodegradation of hexavalent chromium (Cr+6) in wastewater using Pseudomonas sp. and Bacillus sp. bacterial strains

    Energy Technology Data Exchange (ETDEWEB)

    Qasim, Muhammad [Department of Chemical Engineering, American University of Sharjah (United Arab Emirates)

    2013-07-01

    The recovery of toxic metal compounds is a deep concern in all industries. Hexavalent chromium is particularly worrying because of its toxic influence on human health. In this paper, biodegradation of hexavalent chromium (Cr+6) present in wastewater has been studied using two different bacterial strains; Pseudomonas sp. and Bacillus sp. A chemostat (with and without recycle of cells) with 10 L liquid culture volume was used to study the substrate and the biomass cell concentrations with time. Also, the degree of substrate conversion was studied by the varying the dilution rate as an independent parameter. The dilution rate (ratio of feed flow rate to the culture volume) was varied by varying the feed volumetric rate from 110-170 mL/h for inlet hexavalent chromium concentrations of 70 mg/dm3. The results show that a chemostat with recycle gives a better performance in terms of substrate conversion than a chemostat without a recycle. Moreover, the degree of substrate conversion decreases as the dilution rate is increased. Also, Bacillus sp. was found to give higher conversions compared to pseudomonas sp.

  17. Genetic diversity in Fusarium oxysporum f.sp. dianthi and F. redolens f.sp. dianthi

    NARCIS (Netherlands)

    Baayen, R.P.; Dreven, van F.; Krijger, M.C.; Waalwijk, C.

    1997-01-01

    Pathogenic isolates were selected representing all known vegetative compatibility groups (VCGs) and races of Fusarium oxysporum sensu lato from Dianthus spp. On basis of differences in the internal transcribed spacer region of the ribosomal DNA, six VCGs were classified as F. oxysporum f.sp. dianthi

  18. SHEAR STRENGTH IN THE GLUE LINE OF Eucalyptus sp. AND Pinus sp.WOOD

    Directory of Open Access Journals (Sweden)

    Juliana Jerásio Bianche

    Full Text Available ABSTRACT To evaluate the adhesive efficiency on the union of glued joints in a particular temperature and humidity conditions for a specified time the adhesive must be submitted to specific load tests, such as shear in the glue line. The objective of this study was to evaluate the shear strength in the glue line of Eucalyptus sp and Pinus sp.woods. Five adhesives (castor oil, sodium silicate, modified silicate, , PVA and resorcinol-formaldehyde, three weights (150 g/m2, 200 g/m2, and 250 g/m2 and two species (Eucalyptus sp. and Pinus sp. of wood were used. Twelve specimens were obtained from each repetition per treatment, corresponding to 108 specimens that were conditioned at a temperature of 23 ± 1°C and relative humidity of 50 ± 2%. The interaction between the weight and type of adhesive was significant for the shear strength in the glue line of eucalyptus wood. However, no interaction between the weight and the adhesive was found for pinus, only the isolated from the adhesive effect. Chemical bonds originated in the polymerization of resorcinol-formaldehyde adhesives and castor bi-component conferred upon these adhesives the greatest resistance in the glue line. Castor and resorcinol-formaldehyde adhesives showed the highest shear strength values in the line of glue and wood failure. Castor adhesive presented satisfactory performance for bonding of eucalyptus and pine woods.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  20. SP@CE - An SP-based programming model for consumer electronics streaming applications

    NARCIS (Netherlands)

    Varbanescu, Ana Lucia; Nijhuis, Maik; Escribano, Arturo González; Sips, Henk; Bos, Herbert; Bal, Henri

    2007-01-01

    Efficient programming of multimedia streaming applications for Consumer Electronics (CE) devices is not trivial. As a solution for this problem, we present SP@CE, a novel programming model designed to balance the specific requirements of CE streaming applications with the simplicity and efficiency

  1. Eficiencia de pseudomonas sp, rhodopseudomonas sp, micrococcus sp y bacillus sp empleados como cultivos individuales y en consorcio, en la degradación de petróleo diesel ii

    OpenAIRE

    Otiniano García, Nélida Milly Esther

    2010-01-01

    In order to evaluate the efficiency of Pseudomonas sp, Rhodopseudomonas sp, Micrococcus sp, Bacillus sp, and the consortium formed by these four microorganisms in the diesel II petroleum degradation, it was worked in 5 bioreactors of aerated and shaken tank of 1.5 litters of capacity, with speed agitation of 120 rpm, and air flow of 0.5 vvm; in which were placed; 940 mL of Minimum Broth of Davies pH 7.0; 50 mL of diesel II petroleum as source of carbon and 10 mL of a suspension of approx...

  2. Sp(2) covariant quantisation of general gauge theories

    Energy Technology Data Exchange (ETDEWEB)

    Vazquez-Bello, J L

    1994-11-01

    The Sp(2) covariant quantization of gauge theories is studied. The geometrical interpretation of gauge theories in terms of quasi principal fibre bundles Q(M{sub s}, G{sub s}) is reviewed. It is then described the Sp(2) algebra of ordinary Yang-Mills theory. A consistent formulation of covariant Lagrangian quantisation for general gauge theories based on Sp(2) BRST symmetry is established. The original N = 1, ten dimensional superparticle is considered as an example of infinitely reducible gauge algebras, and given explicitly its Sp(2) BRST invariant action. (author). 18 refs.

  3. Sp(2) covariant quantisation of general gauge theories

    International Nuclear Information System (INIS)

    Vazquez-Bello, J.L.

    1994-11-01

    The Sp(2) covariant quantization of gauge theories is studied. The geometrical interpretation of gauge theories in terms of quasi principal fibre bundles Q(M s , G s ) is reviewed. It is then described the Sp(2) algebra of ordinary Yang-Mills theory. A consistent formulation of covariant Lagrangian quantisation for general gauge theories based on Sp(2) BRST symmetry is established. The original N = 1, ten dimensional superparticle is considered as an example of infinitely reducible gauge algebras, and given explicitly its Sp(2) BRST invariant action. (author). 18 refs

  4. Enkapsulasi B. bassiana menggunakan maizena dan daya infeksinya terhadap larva Aedes aegypti, Anopheles sp., Culex sp.

    Directory of Open Access Journals (Sweden)

    Mutiara Widawati

    2015-12-01

    Full Text Available Abstract. Encapsulation formulae of mycoinsecticide have to be able to maintain fungus viability and pathogenicity. This mycoinsecticide was developed as an alternative way to control mosquito borne disease. The aim of this study was to encapsulate Beauveria bassiana as viable storage and have the capability to kill larvae of Aedes aegypti, Anopheles sp. and Culex sp. Mosquito larvae obtained from laboratory reared at health research laboratory; Loka Litbang P2B2 Ciamis. The treatments made in this study were the formu-lation of cornstarch and controls for comparison. This study showed potential formulation of cornstarch encapsulation as a biolarvacidal. Cornstarch formulations proven to be succeed in maintaining fungus viability, however, the pathogenicity of the microcapsule still not effective to kill Aedes, Culex and Anopheles larvae. Keywords: encapsulation, Beauveria bassiana, Ae.aegypti, Anopheles sp., Culex sp. Abstrak. Pembuatan formula bioinsektisida yang optimal sebagai salah satu alternatif untuk pengen-dalian nyamuk vektor perlu di kembangkan. Sediaan mikoinsektisida yang dibuat harus dapat memper-tahankan viabilitas jamur B. bassiana sehingga masih efektif pada saat penggunaannya. Salah satu cara yang digunakan untuk menjaga kestabilan sediaan mikoinsektisida yang berdampak langsung pada via-bilitas jamur adalah dengan menerapkan metode enkapsulasi. Penelitian ini bertujuan untuk meng-hasilkan sediaan mikokapsul dari Beauvaria bassiana melalui proses enkapsulasi menggunakan maizena yang memiliki kapabilitas tinggi sebagai penyimpan B. bassiana dan efektif dalam membunuh larva dan telur Aedes aegypti, Anopheles sp. dan Culex sp. Semua larva uji berasal dari insektarium laboratorium penelitian kesehatan Loka litbang P2B2 Ciamis. Pembuatan enkapsulasi dimulai dengan kultur dan pema-nenan B. bassiana, uji viabilitas, proses enkapsulasi serta uji larvasida di laboratorium. Uji dilakukan dengan satu perlakuan dan satu kontrol untuk

  5. Quality improvement on half-fin anchovy (Setipinna taty) fish sauce by Psychrobacter sp. SP-1 fermentation.

    Science.gov (United States)

    Zheng, Bin; Liu, Yu; He, Xiaoxia; Hu, Shiwei; Li, Shijie; Chen, Meiling; Jiang, Wei

    2017-10-01

    A method of improving fish sauce quality during fermentation was investigated. Psychrobacter sp. SP-1, a halophilic protease-producing bacterium, was isolated from fish sauce with flavor-enhancing properties and non-biogenic amine-producing activity. The performance of Psychrobacter sp. SP-1 in Setipinna taty fish sauce fermentation was investigated further. The inoculation of Psychrobacter sp. SP-1 did not significantly affect pH or NaCl concentration changes (P > 0.05), although it significantly increased total moderately halophilic microbial count, protease activity, total soluble nitrogen content and amino acid nitrogen content, and also promoted the umami taste and meaty aroma (P sauce quality by fermentation. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  6. Penggunaan Streptomyces sp. Sebagai Biokontrol Penyakit Layu Pada Tanaman Cabai Merah (Capsicum annuum L. yang Disebabkan Oleh Fusarium oxysporum f.sp. capsici

    Directory of Open Access Journals (Sweden)

    ANINDA OKTAVIA RAHARINI

    2014-01-01

    Full Text Available A research has been conducted to find out Streptomyces bacteria at Bukit Jimbaran, to inhibitionpotency of Streptomyces sp. to pathogenic fungi Fusarium oxysporum f.sp. capsici, and to find outantifungal activity of Streptomyces filtrate to F.oxysporum f.sp. capsici in chili (Capsicum annuumL. plants. Streptomyces sp. isolation was done by platting method with selective media YMA (ISP4.Identification of Streptomyces sp. used Bergey’s book entitled Manual Determinative Bacteriology.Test inhibition against F.oxysporum f.sp. capsici and in vivo test used by dying the roots of the chili(C.annuum L. plant with F.oxysporum f.sp. capsici and after 30 seconds the roots were dying withStreptomyces sp. culture, furthermore sterile soil on polybag watered by F.oxysporum f.sp. capsicispore and Streptomyces sp. culture at the same time. The result found five isolates Streptomyces sp.with different morphological. The antagonis test showed Streptomyces sp. 4 had ability (82% againstFusarium, Streptomyces sp.1 (72%, Streptomyces sp.2 (64%, Streptomyces sp.3 (76%, andStreptomyces sp. 5 (32%. All Streptomyces suppressed the growth of Fusarium on chili plants inglass house (p<0,05. Streptomyces sp.4 suppressed Fusarium wilt disease in chili from 80% in controlto 8%.

  7. UTILIZAÇÃO DE ADESIVO PVA EM COMPENSADOS DE Pinus sp. E Eucalyptus sp. / UTILIZATION OF PVA ADHESIVES IN Pinus sp. and Eucalyptus sp. PLYWOOD

    Directory of Open Access Journals (Sweden)

    C. I. De Campos

    2014-12-01

    Full Text Available Estudos sobre novos adesivos ou resinas para colagem de madeira e derivados estão sendo realizados com a intenção de diminuir o impacto ambiental sem alterar suas propriedades. Por este motivo, novas formulações de adesivos PVA (Acetato de Polivinila vêm sendo desenvolvidas. Este trabalho testou a utilização deste adesivo na produção de compensado de Eucalyptus sp. e Pinus sp., com tempo e temperatura de prensagem, respectivamente, de 10 minutos e90°C. Foram realizados os ensaios físicos de densidade, teor de umidade e absorção, e os ensaios mecânicos de flexão estática e de resistência ao cisalhamento na linha de cola, todos de acordo com as normas ABNT. Obtiveram-se bons resultados com relação à resistência ao cisalhamento na linha de cola, a qual foi superior para os adesivos PVA, se comparados com compensados produzidos com ureia-formaldeído e o fenol-formaldeído, enquanto que os resultados de MOE e MOR apresentaram-se inferiores em ambos os casos. 

  8. Microbial transformation of citral by Penicillium sp..

    Science.gov (United States)

    Esmaeili, Akbar; Tavassoli, Afsaneh

    2010-01-01

    Thymol is present in the essential oils from herbs and spices, such as thyme. It is produced by these plant species as a chemical defense against phytopathogenic microorganisms. Therefore, this compound has attracted great attention in food industry, i.e., it has been used as a natural preservative in foods such as cheese to prevent fungal growth. Previous studies concerning the biotransformation of nerol by Penicillium sp. and microbial transformation of citral by sporulated surface cultures method (SSCM) of Penicillium digitatum have been reported. The objective of this research was to study the pathway involved during biotransformation of citral by Penicillium sp. using two methods. The culture preparation was done using different microbial methods and incubation periods to obtain Penicillium for citral biotransformation. The biotransformation products were identified by gas chromatography (GC) and gas chromatography/mass spectroscopy (GC/MS). A comparison of the two methods showed that SSCM was more effective, its major products were thymol (21.5 %), geranial (18.6 %) and nerol (13.7 %). LM produced only one compound — thymol — with a low efficiency.

  9. Burkholderia cordobensis sp. nov., from agricultural soils.

    Science.gov (United States)

    Draghi, Walter O; Peeters, Charlotte; Cnockaert, Margo; Snauwaert, Cindy; Wall, Luis G; Zorreguieta, Angeles; Vandamme, Peter

    2014-06-01

    Two Gram-negative, rod-shaped bacteria were isolated from agricultural soils in Córdoba province in central Argentina. Their 16S rRNA gene sequences demonstrated that they belong to the genus Burkholderia, with Burkholderia zhejiangensis as most closely related formally named species; this relationship was confirmed through comparative gyrB sequence analysis. Whole-cell fatty acid analysis supported their assignment to the genus Burkholderia. Burkholderia sp. strain YI23, for which a whole-genome sequence is available, represents the same taxon, as demonstrated by its highly similar 16S rRNA (100% similarity) and gyrB (99.1-99.7%) gene sequences. The results of DNA-DNA hybridization experiments and physiological and biochemical characterization further substantiated the genotypic and phenotypic distinctiveness of the Argentinian soil isolates, for which the name Burkholderia cordobensis sp. nov. is proposed, with strain MMP81(T) ( = LMG 27620(T) = CCUG 64368(T)) as the type strain. © 2014 IUMS.

  10. The Effect of Acupuncture to SP6 on Skin Temperature Changes of SP6 and SP10: An Observation of “Deqi”

    Directory of Open Access Journals (Sweden)

    Jia-Min Yang

    2014-01-01

    Full Text Available Background. Deqi sensation is a complex but an important component for acupuncture effect. In this study, we tried to observe the relationship between Deqi and skin temperature changes and whether there was some relativity between Deqi and needle stimulations on cold congealing and dysmenorrhea rat model. Thirty-two female Sprague Dawley (SD rats were randomly divided into four groups (Saline Control Group, Model Group, Group A with strong stimulation, and Group B with small stimulation. Group A and Group B were performed with different stimulations. We found that, compared with saline control group, model group, and Group B, Group A showed that the skin temperature changes on right acupoint SP6 and SP10 increased significantly at 5 min–10 min interval. The skin temperature changes on left SP6 decreased at instant–5 min interval. The skin temperature changes on right SP10 decreased significantly at instant–5 min interval and 10 min–20 min interval. Thermogenic action along Spleen Meridian of Foot Greater Yin was manifested as simultaneous skin temperature increase on right SP6 and SP10 at 5 min–10 min interval after needling SP6, which was helpful to illustrate the relationship between the characteristic of Deqi and needle stimulations.

  11. MALDI-TOF MS as a Tool To Detect a Nosocomial Outbreak of Extended-Spectrum-β-Lactamase- and ArmA Methyltransferase-Producing Enterobacter cloacae Clinical Isolates in Algeria.

    Science.gov (United States)

    Khennouchi, Nour Chems el Houda; Loucif, Lotfi; Boutefnouchet, Nafissa; Allag, Hamoudi; Rolain, Jean-Marc

    2015-10-01

    Enterobacter cloacae is among the most important pathogens responsible for nosocomial infections and outbreaks. In this study, 77 Enterobacter isolates were collected: 27 isolates from Algerian hospitals (in Constantine, Annaba, and Skikda) and 50 isolates from Marseille, France. All strains were identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). Antibiotic susceptibility testing was performed by the disk diffusion method. PCR was used to detect extended-spectrum-beta-lactamase (ESBL)-encoding, fluoroquinolone resistance-encoding, and aminoglycoside-modifying enzyme (AME) genes. Epidemiological typing was performed using MALDI-TOF MS with data mining approaches, along with multilocus sequence typing (MLST). Sixty-eight isolates (27 from Algeria, 41 from Marseille) were identified by MALDI-TOF MS as E. cloacae. Resistance to antibiotics in the Algerian isolates was significantly higher than that in the strains from Marseille, especially for beta-lactams and aminoglycosides. Eighteen of the 27 Algerian isolates and 11 of the 41 Marseille isolates possessed at least one ESBL-encoding gene: blaCTX-M and/or blaTEM. AME genes were detected in 20 of the 27 Algerian isolates and 8 of the 41 Marseille isolates [ant(2″)-Ia, aac(6')-Ib-cr, aadA1, aadA2, and armA]. Conjugation experiments showed that armA was carried on a transferable plasmid. MALDI-TOF typing showed three separate clusters according to the geographical distribution and species level. An MLST-based phylogenetic tree showed a clade of 14 E. cloacae isolates from a urology unit clustering together in the MALDI-TOF dendrogram, suggesting the occurrence of an outbreak in this unit. In conclusion, the ability of MALDI-TOF to biotype strains was confirmed, and surveillance measures should be implemented, especially for Algerian patients hospitalized in France. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  12. Integrative Gene Cloning and Expression System for Streptomyces sp. US 24 and Streptomyces sp. TN 58 Bioactive Molecule Producing Strains

    Directory of Open Access Journals (Sweden)

    Samiha Sioud

    2009-01-01

    Full Text Available Streptomyces sp. US 24 and Streptomyces sp. TN 58, two strains producing interesting bioactive molecules, were successfully transformed using E. coli ET12567 (pUZ8002, as a conjugal donor, carrying the integrative plasmid pSET152. For the Streptomyces sp. US 24 strain, two copies of this plasmid were tandemly integrated in the chromosome, whereas for Streptomyces sp. TN 58, the integration was in single copy at the attB site. Plasmid pSET152 was inherited every time for all analysed Streptomyces sp. US 24 and Streptomyces sp. TN 58 exconjugants under nonselective conditions. The growth, morphological differentiation, and active molecules production of all studied pSET152 integrated exconjugants were identical to those of wild type strains. Consequently, conjugal transfer using pSET152 integration system is a suitable means of genes transfer and expression for both studied strains. To validate the above gene transfer system, the glucose isomerase gene (xylA from Streptomyces sp. SK was expressed in strain Streptomyces sp. TN 58. Obtained results indicated that heterologous glucose isomerase could be expressed and folded effectively. Glucose isomerase activity of the constructed TN 58 recombinant strain is of about eighteenfold higher than that of the Streptomyces sp. SK strain. Such results are certainly of importance due to the potential use of improved strains in biotechnological process for the production of high-fructose syrup from starch.

  13. Effect of garlic solution to Bacillus sp. removal

    Science.gov (United States)

    Zainol, N.; Rahim, S. R.

    2018-04-01

    Biofilm is a microbial derived sessile community characterized by cells that are irreversibly attached to a substratum or interface to each other, embedded in a matrix of extracellular polymeric substances that they have produced. Bacillus sp. was used as biofilm model in this study. The purpose of this study is to determine the effect of Garlic solution in term of ratio of water and Garlic solution (W/G) and ratio of Garlic solution to Bacillus sp. (GS/B) on Bacillus sp removal. Garlic solution was used to remove Bacillus sp. In this study, Garlic solution was prepared by crushing the garlic and mixed it with water. the Garlic solution was added into Bacillus sp. mixture and mixed well. The mixture then was spread on nutrient agar. The Bacillus sp. weight on agar plate was measured by using dry weight measurement method. In this study, initially Garlic solution volume and Garlic solution concentration were studied using one factor at time (OFAT). Later two-level-factorial analysis was done to determine the most contributing factor in Bacillus sp. removal. Design Expert software (Version 7) was used to construct experimental table where all the factors were randomized. Bacilus sp removal was ranging between 42.13% to 99.6%. The analysis of the results showed that at W/G of 1:1, Bacillus sp. removal increased when more Garlic solution was added to Bacillus sp. Effect of Garlic solution to Bacillus sp. will be understood which in turn may be beneficial for the industrial purpose.

  14. Rhodotorula rosulata sp. nov., Rhodotorula silvestris sp. nov. and Rhodotorula straminea sp. nov., novel myo-inositol-assimilating yeast species in the Microbotryomycetes.

    Science.gov (United States)

    Golubev, Wladyslav I; Scorzetti, Gloria

    2010-10-01

    Three novel species are described as Rhodotorula rosulata sp. nov. (type strain VKM Y-2962(T) =CBS 10977(T)), Rhodotorula silvestris sp. nov. (type strain VKM Y-2971(T) =CBS 11420(T)) and Rhodotorula straminea sp. nov. (type strain VKM Y-2964(T) =CBS 10976(T)) based on the study of eight isolates from needle litter. The new species, phylogenetically located within the Microbotryomycetes, are related to glucuronate-assimilating species of the genus Rhodotorula. Sequencing of the D1/D2 domains of the LSU rDNA gene and the internal transcribed spacer (ITS) region, as well as physiological characterization, revealed their distinct taxonomic positions.

  15. Potential topical natural repellent against Ae. aegypti, Culex sp. and Anopheles sp. mosquitoes

    Directory of Open Access Journals (Sweden)

    Dewi Nur Hodijah

    2014-08-01

    Full Text Available AbstrakLatar belakang:Minyak atsiri daun sirih diketahui mempunyai daya proteksi. Dibuatkan losion berdasarkan pengantar sediaan farmasi yang ditambahkan minyak atsiri daun nilam. Sediaan losion dipilih agar dapat menempel lebih lama di permukaan kulit. Tujuan penelitian ini untuk membandingkan daya proteksi antara losion dengan penambahan minyak nilam dan losion tanpa penambahan minyak nilam dibandingkan daya proteksi dengan DEET. Metode: Penelitian ini merupakan penelitian eksperimental laboratorium. Semua nyamuk uji berasal dari insektarium laboratorium penelitian kesehatan Loka litbang P2B2 Ciamis. Konsentrasi minyak atsiri daun sirih dalam losion adalah 4%; konsentrasi minyak nilam sebagai zat pengikat adalah 0,4%. Formula yang digunakan yaitu formula dasar yang ada pada pengantar sediaan farmasi. Uji repelensi dilakukan dengan menggunakan metoda yang direkomendasikan oleh Komisi pestisida.Hasil: Dihasilkan formulasi losion yang stabil dan masih memenuhi standar formulasi sediaan. Berdasarkan hasil, diperoleh data bahwa DEET dan losion hasil modifikasi memiliki rata-rata daya proteksi di atas 90% selama 6 jam terhadap nyamuk Ae.aegypti dan Culex sp. Kesimpulan: Penambahan minyak nilam pada losion sirih dapat meningkatkan daya proteksi terhadap hinggapan nyamuk Ae. aegypti dan Culex sp. (Health Science Indones 2014;1:44-8Kata kunci:repelen alamiah, minyak atsiri, daun sirih, daun nilam, Ae. aegypti, Culex sp.AbstractBackground: Betel leaf essential oil lotion has been known to have insect repellent properties. A lotion was made based on a pharmaceutical formula from a monograph where patchouli leaf essential oil was added. A lotion preparation was intended to enhance adherence of the formula on the surface of the skin. The purpose of this study was to compare protection percentage of lotion with patchouli oil and without patchouli oil lotion compared to DEET.Methods: This study is an experimental laboratory-based research. All mosquitoes

  16. Kroyeria deetsi n.sp. (Kroyeriidae: Siphonostomatoida), a parasitic ...

    African Journals Online (AJOL)

    Kroyeria deetsi n.sp. (Kroyeriidae: Siphonostomatoida) is described from both sexes collected from the gills of spinner sharks, Carcharhinus brevipinna (Müller & Henle, 1839), captured in the Indian Ocean off the coast of South Africa. Kroyeria deetsi n.sp. can easily be distinguished from all of its congeners because the ...

  17. Enhancement of clavulanic acid production by Streptomyces sp MU ...

    African Journals Online (AJOL)

    Purpose: To enhance clavulanic acid production using UV-mutagenesis on Streptomyces sp. NRC77. Methods: UV-mutagenesis was used to study the effect of Streptomyces sp. NRC77 on CA production. Phenotypic and genotypic identification methods of the promising mutant strain were characterized. Optimization of the ...

  18. HANSENULA WICKERHAMII SP. N., A NEW YEAST FROM FINNISH SOIL

    Science.gov (United States)

    Capriotti, Augusto

    1961-01-01

    Capriotti, Augusto (l'Università di Perugia, Perugia, Italy). Hansenula wickerhamii sp. n., a new yeast from Finnish soil. J. Bacteriol. 82:259–360. 1961.—Hansenula wickerhamii sp. n. is described; it was isolated from a Finnish soil, and is named in honor of Lynferd J. Wickerham. Images PMID:13690638

  19. Truncated recombinant human SP-D attenuates emphysema and type II cell changes in SP-D deficient mice

    Directory of Open Access Journals (Sweden)

    Mühlfeld Christian

    2007-10-01

    Full Text Available Abstract Background Surfactant protein D (SP-D deficient mice develop emphysema-like pathology associated with focal accumulations of foamy alveolar macrophages, an excess of surfactant phospholipids in the alveolar space and both hypertrophy and hyperplasia of alveolar type II cells. These findings are associated with a chronic inflammatory state. Treatment of SP-D deficient mice with a truncated recombinant fragment of human SP-D (rfhSP-D has been shown to decrease the lipidosis and alveolar macrophage accumulation as well as production of proinflammatory chemokines. The aim of this study was to investigate if rfhSP-D treatment reduces the structural abnormalities in parenchymal architecture and type II cells characteristic of SP-D deficiency. Methods SP-D knock-out mice, aged 3 weeks, 6 weeks and 9 weeks were treated with rfhSP-D for 9, 6 and 3 weeks, respectively. All mice were sacrificed at age 12 weeks and compared to both PBS treated SP-D deficient and wild-type groups. Lung structure was quantified by design-based stereology at the light and electron microscopic level. Emphasis was put on quantification of emphysema, type II cell changes and intracellular surfactant. Data were analysed with two sided non-parametric Mann-Whitney U-test. Main Results After 3 weeks of treatment, alveolar number was higher and mean alveolar size was smaller compared to saline-treated SP-D knock-out controls. There was no significant difference concerning these indices of pulmonary emphysema within rfhSP-D treated groups. Type II cell number and size were smaller as a consequence of treatment. The total volume of lamellar bodies per type II cell and per lung was smaller after 6 weeks of treatment. Conclusion Treatment of SP-D deficient mice with rfhSP-D leads to a reduction in the degree of emphysema and a correction of type II cell hyperplasia and hypertrophy. This supports the concept that rfhSP-D might become a therapeutic option in diseases that are

  20. Solar drying of rose (Rosa sp.) petals

    Energy Technology Data Exchange (ETDEWEB)

    Balladin, D.A.; Headley, Oliver [University of the West Indies, Center for Resource Management and Environmental Studies, St. Michael (Barbados)

    1999-10-01

    The rose (Rosa sp.) petals can be dried after 2 days at about 30degC reaching an equilibrium moisture content after 16 h using the solar wire basket dryer. The initial moisture content (wet wt basis) and final moisture content (dry wt basis), determined by the Dean-Stark toluene were 65.7 and 25.2% respectively. The intensity of the rose red coloured pigment (pelargonidin) decreased by a factor of 2.5 after drying. The pelargonidin ethanoic extract as an acid-base indicator, has a K{sub 4} value of 1 x 10{sup -4} mol 1{sup -1} and pH of end point 4 and imbibed on filter paper and allowed to air dry for 5 min showed excellent properties as acid-based test tapes. (Author)

  1. Electron microscope study of Sarcocystis sp

    Science.gov (United States)

    Zeve, V.H.; Price, D.L.; Herman, C.M.

    1966-01-01

    Sarcocystis sp. obtained from wild populations of grackles, Quiscalus quiscula (Linn.), were examined to clarify the effect of the parasite on the host. Electron micrographs are presented to show areas of muscle destruction adjacent to the parasite which appear to be mechanically produced by the parasite. The microtubules within the villus-like projections of the cyst suggest that their possible function is absorptive and/or conductive with regard to the production of a toxin or the conveyance of nutritive material to the developing cells. The proposed function of submembranous filaments and their relation to the conoid is discussed. Similarities in the ultrastructure to Toxoplasma and other protozoa tend to negate the relegation of Sarcocystis to the fungi and further emphasize its protozoan nature.

  2. Polyhydroxybutyrate accumulation by a Serratia sp.

    Science.gov (United States)

    Lugg, Harriet; Sammons, Rachel L; Marquis, Peter M; Hewitt, Christopher J; Yong, Ping; Paterson-Beedle, Marion; Redwood, Mark D; Stamboulis, Artemis; Kashani, Mitra; Jenkins, Mike; Macaskie, Lynne E

    2008-03-01

    A strain of Serratia sp. showed intracellular electron-transparent inclusion bodies when incubated in the presence of citrate and glycerol 2-phosphate without nitrogen source following pre-growth under carbon-limitation in continuous culture. About 1.3 mmol citrate were consumed per 450 mg biomass, giving a calculated yield of maximally 55% of stored material per g of biomass dry wt. The inclusion bodies were stained with Sudan Black and Nile Red (NR), suggesting a lipid material, which was confirmed as polyhydroxybutyrate (PHB) by analysis of molecular fragments by GC and by FTIR spectroscopy of isolated bio-PHB in comparison with reference material. Multi-parameter flow cytometry in conjunction with NR fluorescence, and electron microscopy, showed that not all cells contained heavy PHB bodies, suggesting the potential for increasing the overall yield. The economic attractiveness is enhanced by the co-production of nanoscale hydroxyapatite (HA), a possible high-value precursor for bone replacement materials.

  3. In vitro rootting of Dioscoreas sp.

    Directory of Open Access Journals (Sweden)

    Irma Quintero

    2003-07-01

    Full Text Available The Universidad de Córdoba s Vegetal Tissue Culture Laboratory evaluated the effect of naphthalenacetic acid (NAA on in vitro rooting of three yam cultivars (Dioscorea sp. in 2000. The effect of four hormone levels (0, 0.3, 0.6 and 0.9 mg/1 was studied on three yam cultivars (Diamantes-22,003 and 005. A random experimental design was used employing 4x3 factorial arrangement and 20 repetitions; each experimental unit consisted of a glass receptacle containing the culture medium and the explant (one segment nodal. The variables considered were the number of roots and their thickness, culture medium oxidation and callus production. Findings showed that both the hormone and genotype had an effect on all those variables considered in the study and interaction was significant (P

  4. Predicting fuel performance for SP-100 conditions

    International Nuclear Information System (INIS)

    Baars, R.E.

    1985-01-01

    This paper reports on methods for analyzing fuel designs proposed for the thermionic and thermoelectric concepts for SP-100 application. The proposed fuel design for the thermionic concept consisted of fully-enriched oxide fuel clad in chemical vapor deposition (CVD) tungsten, which also served as the emitter for the thermionic fuel element (TFE). The fuel density was 95% of theoretical with the linear heat rate flattened radially by removing fuel from the center of the fuel pellet. The fuel inner diameter varied from approx.0.45 in. at the core center to zero at the edge of the core. The as-fabricated gap between fuel and emitter was 10 mils radial. The emitter thickness was 80 mils, and the outer diameter was 1.099 in. The LIFE-4 code was used for evaluation of this concept after extensive review of the code and development of a procedure that corrects certain deficiencies noted in analysis of several tests

  5. Taxonomic evaluation of the genus Enterobacter based on multilocus sequence analysis (MLSA): proposal to reclassify E. nimipressuralis and E. amnigenus into Lelliottia gen. nov. as Lelliottia nimipressuralis comb. nov. and Lelliottia amnigena comb. nov., respectively, E. gergoviae and E. pyrinus into Pluralibacter gen. nov. as Pluralibacter gergoviae comb. nov. and Pluralibacter pyrinus comb. nov., respectively, E. cowanii, E. radicincitans, E. oryzae and E. arachidis into Kosakonia gen. nov. as Kosakonia cowanii comb. nov., Kosakonia radicincitans comb. nov., Kosakonia oryzae comb. nov. and Kosakonia arachidis comb. nov., respectively, and E. turicensis, E. helveticus and E. pulveris into Cronobacter as Cronobacter zurichensis nom. nov., Cronobacter helveticus comb. nov. and Cronobacter pulveris comb. nov., respectively, and emended description of the genera Enterobacter and Cronobacter.

    Science.gov (United States)

    Brady, Carrie; Cleenwerck, Ilse; Venter, Stephanus; Coutinho, Teresa; De Vos, Paul

    2013-07-01

    The taxonomy of Enterobacter has a complicated history, with several species transferred to and from this genus. Classification of strains is difficult owing to its polyphyletic nature, based on 16S rRNA gene sequences. It has been previously acknowledged that Enterobacter contains species which should be transferred to other genera. In an attempt to resolve the taxonomy of Enterobacter, MLSA based on partial sequencing of protein-encoding genes (gyrB, rpoB, infB and atpD) was performed on the type strains and reference strains of Enterobacter, Cronobacter and Serratia species, as well as members of the closely related genera Citrobacter, Klebsiella, Kluyvera, Leclercia, Mangrovibacter, Raoultella and Yokenella. Phylogenetic analyses of the concatenated nucleotide sequences revealed that Enterobacter can be divided into five strongly supported MLSA groups, suggesting that the species should be reclassified into five different genera. Further support for this was provided by a concatenated amino acid tree, phenotypic characteristics and fatty acid profiles, enabling differentiation of the MLSA groups. Three novel genera are proposed: Lelliottia gen. nov., Pluralibacter gen. nov. and Kosakonia gen. nov. and the following new combinations: Lelliottia nimipressuralis comb. nov., Lelliottia amnigena comb. nov., Pluralibacter gergoviae comb. nov., Pluralibacter pyrinus comb. nov., Kosakonia cowanii comb. nov., Kosakonia radicincitans comb. nov., Kosakonia oryzae comb. nov., Kosakonia arachidis comb. nov., Cronobacter helveticus comb. nov. and Cronobacter pulveris comb. nov. Additionally, the novel epithet Cronobacter zurichensis nom. nov. is proposed for the reclassification of Enterobacter turicensis into the genus Cronobacter, as Cronobacter turicensis (Iversen et al., 2008) is already in use. Copyright © 2013 Elsevier GmbH. All rights reserved.

  6. Aspergillus waksmanii sp. nov. and Aspergillus marvanovae sp. nov., two closely related species in section Fumigati

    DEFF Research Database (Denmark)

    Hubka, Vit; Peterson, Stephen W.; Frisvad, Jens Christian

    2013-01-01

    Two new and phylogenetically closely related species in Aspergillus section Fumigati are described and illustrated. Homothallic Aspergillus waksmanii sp. nov. was isolated from New Jersey soil (USA) and is represented by the ex-type isolate NRRL 179T (=CCF 4266T=Thom 4138.HS2T=IBT 31900T......). Aspergillus marvanovae sp. nov. was isolated from water with high boracic acid anions content in Dukovany nuclear power station (Czech Republic). The sexual stage of this species is unknown, but the MAT1-1 locus was successfully amplified suggesting that the species is probably heterothallic and teleomorphic...... but is represented by only the ex-type isolate CCM 8003T (=CCF 4037T=NRRL 62486T=IBT 31279T=IFM 60873T). Both species can be distinguished from all previously described species in section Fumigati based on morphology, maximum growth temperature, sequence data from five unlinked loci and unique secondary metabolites...

  7. Six New Polyacetylenic Alcohols from the Marine Sponges Petrosia sp. and Halichondria sp.

    Science.gov (United States)

    Gabriel, Adeyemi Francis; Li, Zhen; Kusuda, Ryouhei; Tanaka, Chiaki; Miyamoto, Tomofumi

    2015-01-01

    Six new polyacetylenic alcohols, termed strongylotriols A and B; pellynols J, K, and L; and isopellynol A, together with three known polyacetylenic alcohols, pellynols A, B, and C were isolated from the marine sponges Petrosia sp., and Halichondria sp. collected in Okinawa, Japan. Their planer structures were determined based on 2D-NMR and mass spectrometric analysis of the degraded products by RuCl3 oxidation. The absolute stereochemistry of isolates was examined by their Mosher's esters. The strongylotriols were found to be optically pure compounds, whereas the pellynols are diastereomeric mixtures at the C-6 position. Proliferation experiments using the HeLa and K562 cell lines suggested that the essential structural units for activity are the "hexa-2,4-diyn-1,6-diol" and "pent-1-en-4-yn-3-ol" on the termini.

  8. Kinerja probiotik Bacillus sp. pada pendederan benih ikan lele Clarias sp. yang diinfeksi Aeromonas hydrophila

    Directory of Open Access Journals (Sweden)

    , Sukenda

    2016-12-01

    Full Text Available ABSTRACT This experiment was conducted to assess performance of Bacillus sp. probiotic on catfish juvenile Clarias sp. infected by Aeromonas hydrophila. The probiotic content in the diets were 0% (K+ and K-, 1%, and 2% in duplicates. This experiment used randomized design with four treatments and two replications. Juveniles with average body weight of 3.22±0.15 g/fish were reared in the 1.5×2.8×0.5 m3 pond with density of 800 fish/pond. Fish were reared for 30 days and fed three times a day at rate 8% of  total body weight. At day 31, catfish were challenged by A. hydrophila 0.1 mL (106 cfu/mL. Post infection observation was carried out ten days with density 10 fish/aquaria. The result showed that fish fed diet containing 2% probiotic gave the best probiotic performance with survival rate of catfish 83.33% after challenged, spesific growth rate 5.40%, and 0,75 of feed conversion ratio. The results of the blood profile showed significantly better results in the treatment of probiotics compared to the positive control after challenge test A. hydrophila. Probiotic Bacillus sp. has given as much as 2% on feed provides better performance on catfish juvenile. Keywords: probiotic, Bacillus sp., A. hydrophila, catfish juvenille, growth  ABSTRAK Penelitian ini bertujuan untuk menguji kinerja probiotik Bacillus sp. dalam pakan pada pendederan benih ikan lele Clarias sp. yang diinfeksi bakteri Aeromonas hydrophila. Penelitian ini menggunakan rancangan acak lengkap dengan empat perlakuan yaitu kandungan probiotik dalam pakan perlakuan yaitu 0% (K+ dan K-, 1%,  dan 2%, masing-masing dengan dua ulangan. Ikan lele yang digunakan memiliki bobot rata-rata 3,22±0,15 g/ekor, dipelihara dalam kolam terpal berukuran 1,5×2,8×0,5 m3 dengan kepadatan 800 ekor/kolam. Ikan dipelihara selama 30 hari dengan frekuensi pemberian pakan tiga kali sehari sebanyak 8% dari bobot tubuh ikan. Hari ke-31 benih lele diinjeksi bakteri A. hydrophila dosis 0,1 m

  9. Descriptions of Deladenus albizicus n. sp. and D. processus n. sp. (Nematoda: Hexatylina) from Haryana, India.

    Science.gov (United States)

    Tomar, V V S; Somvanshi, Vishal S; Bajaj, Harish K

    2015-03-01

    Two different nematodes were isolated from the bark of Albizia lebbeck trees; one from insect infested and another from noninfested, healthy tree. Based on the biological, morphological, and molecular evidences, the nematodes are described as Deladenus albizicus n. sp. and D. processus n. sp. (Nematoda: Hexatylina). Deladenus albizicus n. sp., isolated from insect-infested tree, multiplied on the fungus Nigrospora oryzae. Myceliophagous females of this nematode reproduced by parthenogenesis and spermathecae were indistinct. Infective females, readily produced in the cultures, are dorsally curved. Only one type of males containing small-sized sperms in their genital tracts were produced in the culture. Myceliophagous females: L = 0.75 to 1.71 mm, a = 32.3 to 50.8, b = 9.3 to 11.2, b' = 5.2 to 7.3, c = 27.2 to 35.6, V = 91.0 to 93.3, c' = 2.0 to 2.9, stylet = 11 to 12 µm, excretory pore in the region of median pharyngeal bulb, 43 to 47 µm anterior to hemizonid. Deladenus processus n. sp., isolated from bark of healthy A. lebbeck tree, was cultured on Alternaria alternata. Myceliophagous females reproduced by amphimixis and their spermathecae contained rounded sperms. Infective females were never produced, even in old cultures. Myceliophagous females: L = 0.76 to 0.99 mm, a = 34 to 49, b = 13.3 to 17.7, b' = 3.8 to 5.8, c = 19.6 to 22.8, V = 92.2 to 93.5, c' = 2.7 to 3.5, stylet = 6 to 7 µm, excretory pore in the proximity of hemizonid, tail conoid, tapering from both sides to a long pointed central process. It is proposed to classify Deladenus species in three groups: durus, siricidicola, and laricis groups based on female and spermatogonia dimorphism, mode of reproduction, and insect parasitism.

  10. Neorickettsia risticii, Rickettsia sp. and Bartonella sp. in Tadarida brasiliensis bats from Buenos Aires, Argentina.

    Science.gov (United States)

    Cicuttin, Gabriel L; De Salvo, María N; La Rosa, Isabel; Dohmen, Federico E Gury

    2017-06-01

    Bats are potential reservoirs of many vector-borne bacterial pathogens. The aim of the present study was to detect species of Anaplasma, Ehrlichia, Neorickettsia, Rickettsia, Borrelia and Bartonella in Brazilian free-tailed bats (Tadarida brasiliensis, Molossidae) from Buenos Aires city, Argentina. Between 2012 and 2013, 61 T. brasiliensis from urban areas of Buenos Aires city were studied. The samples were molecularly screened by PCR and sequencing. Five bats (8.2%) were positive to Neorickettsia risticii, one (1.6%) was positive to Rickettsia sp. and three bats (4.9%) to Bartonella sp. For molecular characterization, the positive samples were subjected to amplification and sequencing of a fragment of p51 gene for N. risticii, a fragment of citrate synthase gene (gltA) for Rickettsia genus and a fragment of gltA for Bartonella genus. Phylogenetic tree was constructed using the maximum-likelihood method. Phylogenetic analysis of N. risticii detect in our study revealed that it relates to findings in the USA West Coast; Rickettsia sp. detected is phylogenetically within R. bellii group, which also includes many other Rickettsia endosymbionts of insects; and Bartonella sp. found is related to various Bartonella spp. described in Vespertilionidae bats, which are phylogenetically related to Molossidae. Our results are in accordance to previous findings, which demonstrate that insectivorous bats could be infected with vector-borne bacteria representing a potential risk to public health. Future research is necessary to clarify the circulation of these pathogens in bats from Buenos Aires. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Endosulfan induced alteration in bacterial protein profile and RNA yield of Klebsiella sp. M3, Achromobacter sp. M6, and Rhodococcus sp. M2.

    Science.gov (United States)

    Singh, Madhu; Singh, Dileep Kumar

    2014-01-30

    Three bacterial strains identified as Klebsiella sp. M3, Achromobacter sp. M6 and Rhodococcus sp. M2 were isolated by soil enrichment with endosulfan followed by shake flask enrichment technique. They were efficiently degrading endosulfan in the NSM (non sulfur medium) broth. Degradation of endosulfan was faster with the cell free extract of bacterial cells grown in the sulfur deficient medium (NSM) supplemented with endosulfan than that of nutrient rich medium (Luria Bertani). In the cell free extract of NSM supplemented with endosulfan as sole sulfur source, a unique band was visualized on SDS-PAGE but not with magnesium sulfate as the sole sulfur source in NSM and LB with endosulfan. Expression of a unique polypeptide band was speculated to be induced by endosulfan under sulfur starved condition. These unique polypeptide bands were identified as OmpK35 protein, sulfate binding protein and outer membrane porin protein, respectively, in Klebsiella sp. M3, Achromobacter sp. M6 and Rhodococcus sp. M2. Endosulfan showed dose dependent negative effect on total RNA yield of bacterial strains in nutrient rich medium. Absence of plasmid DNA indicated the presence of endosulfan metabolizing gene on genomic DNA. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. From spent graphite to amorphous sp2+sp3 carbon-coated sp2 graphite for high-performance lithium ion batteries

    Science.gov (United States)

    Ma, Zhen; Zhuang, Yuchan; Deng, Yaoming; Song, Xiaona; Zuo, Xiaoxi; Xiao, Xin; Nan, Junmin

    2018-02-01

    Today, with the massive application of lithium ion batteries (LIBs) in the portable devices and electric vehicles, to supply the active materials with high-performances and then to recycle their wastes are two core issues for the development of LIBs. In this paper, the spent graphite (SG) in LIBs is used as raw materials to fabricate two comparative high-capacity graphite anode materials. Based on a microsurgery-like physical reconstruction, the reconstructed graphite (RG) with a sp2+sp3 carbon surface is prepared through a microwave exfoliation and subsequent spray drying process. In contrast, the neural-network-like amorphous sp2+sp3 carbon-coated graphite (AC@G) is synthesized using a self-reconfigurable chemical reaction strategy. Compared with SG and commercial graphite (CG), both RG and AC@G have enhanced specific capacities, from 311.2 mAh g-1 and 360.7 mAh g-1 to 409.7 mAh g-1 and 420.0 mAh g-1, at 0.1C after 100 cycles. In addition, they exhibit comparable cycling stability, rate capability, and voltage plateau with CG. Because the synthesis of RG and AC@G represents two typical physical and chemical methods for the recycling of SG, these results on the sp2+sp3 carbon layer coating bulk graphite also reveal an approach for the preparation of high-performance graphite anode materials derived from SG.

  13. Wnt-mediated down-regulation of Sp1 target genes by a transcriptional repressor Sp5

    Czech Academy of Sciences Publication Activity Database

    Fujimura, Naoko; Vacík, Tomáš; Machoň, Ondřej; Vlček, Čestmír; Scalabrin, S.; Speth, M.; Diep, D.; Krauss, S.; Kozmik, Zbyněk

    2007-01-01

    Roč. 282, č. 2 (2007), s. 1225-1237 ISSN 0021-9258 Institutional research plan: CEZ:AV0Z50520514 Keywords : Wnt -mediated signaling * Sp5 transcription factor * Sp1 target genes Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.581, year: 2007

  14. Structural Analysis of Planar sp3 and sp2 Films: Diamond-Like Carbon and Graphene Overlayers

    KAUST Repository

    Mansour, Ahmed

    2011-01-01

    pure sp2 as in graphene, carbon nanotubes and fullerenes, to pure sp3 as in diamond. Amorphous and diamond-like carbon consists of a mixture of both hybridizations. This variation in hybridization in carbon materials enables a wide spectrum

  15. Formulation of a minimal nutritional medium for enhanced lipid productivity in Chlorella sp. and Botryococcus sp. using response surface methodology.

    Science.gov (United States)

    Vishwakarma, Rashi; Dhar, Dolly Wattal; Pabbi, Sunil

    2018-03-01

    Chlorella sp. MCC 7 and Botryococcus sp. MCC 31 were investigated to enable large-scale biodiesel production from minimal constituents in the growth medium. Response surface methodology (RSM) was used to maximise the biomass productivity and lipid yield using only nitrogen (N), phosphorus (P) and potassium (K) as urea, single super phosphate and muriate of potash. The optimum values were 0.42 g/L nitrogen; 0.14 g/L phosphorus and 0.22 g/L potassium for Chlorella sp.; and 0.46 g/L; 0.14 g/L and 0.25 g/L for Botryococcus sp. Lipid yield of 42% for Chlorella sp. and 52% in Botryococcus sp. was observed. An enhancement in lipid yield by approximately 55% for Chlorella sp. and 73% for Botryococcus sp. was registered as compared to original nutrient medium. Fourier transform infrared (FTIR) analysis of extracted lipids revealed characteristic bands for triglycerides. This study provided utilisation of a practicable nutrient recipe in the form of N, P, K input for enhanced lipid yield from the selected microalgal strains.

  16. Elevated expression and potential roles of human Sp5, a member of Sp transcription factor family, in human cancers

    International Nuclear Information System (INIS)

    Chen Yongxin; Guo Yingqiu; Ge Xijin; Itoh, Hirotaka; Watanabe, Akira; Fujiwara, Takeshi; Kodama, Tatsuhiko; Aburatani, Hiroyuki

    2006-01-01

    In this report, we describe the expression and function of human Sp5, a member of the Sp family of zinc finger transcription factors. Like other family members, the Sp5 protein contains a Cys2His2 zinc finger DNA binding domain at the C-terminus. Our experiments employing Gal4-Sp5 fusion proteins reveal multiple transcriptional domains, including a N-terminal activity domain, an intrinsic repressive element, and a C-terminal synergistic domain. Elevated expression of Sp5 was noted in several human tumors including hepatocellular carcinoma, gastric cancer, and colon cancer. To study the effects of the Sp5 protein on growth properties of human cancer cells and facilitate the identification of its downstream genes, we combined an inducible gene expression system with microarray analysis to screen for its transcriptional targets. Transfer of Sp5 into MCF-7 cells that expressed no detectable endogenous Sp5 protein elicited significant growth promotion activity. Several of the constitutively deregulated genes have been associated with tumorigenesis (CDC25C, CEACAM6, TMPRSS2, XBP1, MYBL1, ABHD2, and CXCL12) and Wnt/β-Catenin signaling pathways (BAMBI, SIX1, IGFBP5, AES, and p21 WAF1 ). This information could be utilized for further mechanistic research and for devising optimized therapeutic strategies against human cancers

  17. The human luteinizing hormone receptor gene promoter: activation by Sp1 and Sp3 and inhibitory regulation.

    Science.gov (United States)

    Geng, Y; Tsai-Morris, C H; Zhang, Y; Dufau, M L

    1999-09-24

    To understand the transcriptional mechanism(s) of human LH receptor (LHR) gene expression, we have identified the dominant functional cis-elements that regulate the activity of the promoter domain (-1 to -176 bp from ATG). Mutagenesis demonstrated that the promoter activity was dependent on two Sp1 domains (-79 bp, -120 bp) in a transformed normal placental cell (PLC) and the choriocarcinoma JAR cell. Both elements interacted with endogenous Sp1 and Sp3 factors but not with Sp2 or Sp4. In Drosophila SL2 cells, the promoter was activated by either Sp1 or Sp3. An ERE half-site (EREhs) at -174 bp was inhibitory (by 100%), but was unresponsive to estradiol and did not bind the estrogen receptor or orphan receptors ERR1 and SF-1. The 5' upstream sequence (-177 to -2056 bp) inhibited promoter activity in PLC by 60%, but only minimally in JAR cells. Activation of the human LHR promoter through Sp1/3 factors is negatively regulated through EREhs and upstream sequences to exert control of gene expression. Copyright 1999 Academic Press.

  18. PENGGUNAAN EKSTRAK BIOTA LAUTAGLAOPHENIA SP. UNTUK MENGENDALIKANFUSARIUM OXYSPORUM F.SP.VANILLAE PENYEBAB BUSUK BATANG VANILI

    Directory of Open Access Journals (Sweden)

    I KETUT SUADA

    2012-11-01

    Full Text Available The Use of Aglaophenia sp. Marine Biota Extract to Control Fusarium oxysporum f. sp. vanillae, a Pathogen of Vanilla Stem Rot The use of marine biota for organic fungicide material has enormous potential to be developed. The organic fungicide was directed to substitute synthetic fungicide for vanilla cultivation. Application of synthetic fungicide degraded environmental quality, therefore its applications does not support sustainable agriculture. The objective of this research was to know the potence of Aglaopheniain suppressing the growth of F. oxysporum f. sp.vanillae, the pathogen of vanilla stem rot. The research was done in green house in order to find the best substance for formulation of the extract. The substances screened were water, tween-80, and detergents with two different concentrations. Subsequently, two best formulas were chosen to apply in endemic area in Tabanan. The green house and field trial research used Randomized Completely Design with three and five replications respectively. Results showed that tween was the best substance used for formulation and concentration of 0.2% was better than other concentrations. The extract diluted in tween-80 on the concentration of 0.2% showed the lowest rot on stem, longest shoot, and the most leaves on vanilla shoot. Because of its significant performance, the 0.1% extract ofAglaopheniain 0.1% tween-80 was proposed to be the best formula to suppress the vanilla stem rot disease.

  19. A sp2+sp3 hybridized carbon allotrope transformed from AB stacking graphyne and THD-graphene

    Directory of Open Access Journals (Sweden)

    Yu Zhang

    2018-01-01

    Full Text Available New carbon allotropes can be designed by combining sp, sp2 and sp3 three hybridization states. And the hybridization states or coordination numbers of carbon atoms can be changed by applying high pressure on carbon materials. In this study, a common high pressure phase (named as TBBC transformed from AB-stacking graphyne or THD-graphene is predicted. Its kinetic stability is examined using finite displacement method. We find that the sp2 and sp3 hybridized carbon atoms behave different vibration features at high frequency region. Both graphene-like and diamond-like vibration peaks occurs. Phase transition energy barriers from both graphyne and THD-graphene to TBBC are estimated. Electronic structure calculations show that the TBBC is an indirect semiconductor with a bandgap of 0.66 eV. The ideal tensile strength of TBBC is high in [0001] and [11¯00] directions, but is weak along [12¯10] direction.

  20. Kinetics of petroleum oil biodegradation by a consortium of three protozoan isolates (Aspidisca sp., Trachelophyllum sp. and Peranema sp.

    Directory of Open Access Journals (Sweden)

    L. Kachieng’a

    2017-09-01

    Full Text Available Petroleum oil is a complex mixture of substances, the majority of which are hydrocarbons; the latter represent an extremely important and heterogeneous group of compounds that find their way into water resources by anthropogenic or natural ways. The majority of toxic hydrocarbon components of petroleum are biodegradable, where bioremediation using microbial species has become an integral process for the restoration of oil-polluted areas. In this study, three bioremediation processes, namely natural attenuation, nutrient supplementation by adding glucose and biostimulation by adding Tween® 80, were carried out in various petroleum hydrocarbon concentrations in polluted water media using a consortium of three protozoan isolates (Aspidisca sp., Trachelophyllum sp. and Peranema sp.. A first-order kinetics model was fitted to the biodegradation data to evaluate the biodegradation rate and to determine the corresponding half-life time. First-order kinetics satisfactorily described the biodegradation of the petroleum-based contaminants under abiotic conditions. The results showed an increase in the percentage removal of petroleum oil at the lower petroleum concentrations and a gradual percentage decrease in removing petroleum oil residues occurred when there was an increase in the initial concentrations of the petroleum oil: 39%, 27%, 22%, 12%, 10% for various petroleum oil concentrations of 50, 100, 150, 200, 250 mg/L, respectively. A similar trend was also observed in the glucose-supplemented culture media where the reduction was 45% and 78% for petroleum concentrations of 250 mg/L and 50 mg/L, respectively. Biodegradation of between 33 and 90% was achieved at a Tween® 80 concentration of between 50 mg/L and 250 mg/L. The degradation rate constants for the natural attenuation process ranged between ≥0 to ≤0.50, ≥0 to ≤0.35, ≥0 to ≤0.25, ≥0 to ≤ 0.14 and ≥ 0 to ≤0.11 for petroleum oil concentrations varying from 50, 100, 150

  1. Cr(VI) reduction from contaminated soils by Aspergillus sp. N2 and Penicillium sp. N3 isolated from chromium deposits.

    Science.gov (United States)

    Fukuda, Tsubasa; Ishino, Yasuhiro; Ogawa, Akane; Tsutsumi, Kadzuyo; Morita, Hiroshi

    2008-10-01

    Aspergillus sp. N2 and Penicillium sp. N3 are chromate-resistant filamentous fungi that were isolated from Cr(VI) contaminated soil based on their ability to decrease hexavalent chromium levels in the growth medium. After 120 h of growth in a medium containing 50 ppm Cr(VI) at near neutral pH, Aspergillus sp. N2 reduced the Cr(VI) concentration by about 75%. Penicillium sp. N3 was able to reduce the Cr(VI) concentration by only 35%. However, Penicillium sp. N3 reduced the Cr(VI) concentration in the medium by 93% under acidic conditions. Interestingly, the presence of Cu(II) enhanced the Cr(VI) reducing ability of Aspergillus sp. N2 and Penicillium sp. N3 at near neutral pH. Aspergillus sp. N2 and Penicillium sp. N3 reduced the Cr(VI) concentration in the growth medium to a virtually undetectable level within 120 h. For both Aspergillus sp. N2 and Penicillium sp. N3, mycelial seed cultures were more efficient at Cr(VI) reduction than conidium seed cultures. The mechanisms of Cr(VI) reduction in Aspergillus sp. N2 and Penicillium sp. N3 were enzymatic reduction and sorption to mycelia. Enzymatic activity contributed significantly to Cr(VI) reduction. Aspergillus sp. N2 and Penicillium sp. N3 reduced the levels of Cr(VI) in polluted soil samples, suggesting that these strains might be useful for cleaning up chromium-contaminated sites.

  2. Scalability of Parallel Spatial Direct Numerical Simulations on Intel Hypercube and IBM SP1 and SP2

    Science.gov (United States)

    Joslin, Ronald D.; Hanebutte, Ulf R.; Zubair, Mohammad

    1995-01-01

    The implementation and performance of a parallel spatial direct numerical simulation (PSDNS) approach on the Intel iPSC/860 hypercube and IBM SP1 and SP2 parallel computers is documented. Spatially evolving disturbances associated with the laminar-to-turbulent transition in boundary-layer flows are computed with the PSDNS code. The feasibility of using the PSDNS to perform transition studies on these computers is examined. The results indicate that PSDNS approach can effectively be parallelized on a distributed-memory parallel machine by remapping the distributed data structure during the course of the calculation. Scalability information is provided to estimate computational costs to match the actual costs relative to changes in the number of grid points. By increasing the number of processors, slower than linear speedups are achieved with optimized (machine-dependent library) routines. This slower than linear speedup results because the computational cost is dominated by FFT routine, which yields less than ideal speedups. By using appropriate compile options and optimized library routines on the SP1, the serial code achieves 52-56 M ops on a single node of the SP1 (45 percent of theoretical peak performance). The actual performance of the PSDNS code on the SP1 is evaluated with a "real world" simulation that consists of 1.7 million grid points. One time step of this simulation is calculated on eight nodes of the SP1 in the same time as required by a Cray Y/MP supercomputer. For the same simulation, 32-nodes of the SP1 and SP2 are required to reach the performance of a Cray C-90. A 32 node SP1 (SP2) configuration is 2.9 (4.6) times faster than a Cray Y/MP for this simulation, while the hypercube is roughly 2 times slower than the Y/MP for this application. KEY WORDS: Spatial direct numerical simulations; incompressible viscous flows; spectral methods; finite differences; parallel computing.

  3. Genetic polymorphism of horse serum protein 3 (SP3).

    Science.gov (United States)

    Juneja, R K; Sandberg, K; Kuryl, J; Gahne, B

    1989-01-01

    Two-dimensional agarose gel (pH 8.6)-horizontal polyacrylamide gel (pH 9.0) electrophoresis of horse serum samples, followed by general protein staining, revealed genetic polymorphism of an unidentified protein tentatively designated serum protein 3 (SP3). The SP3 fractions appeared distinctly when a 14% concentration of acrylamide was used in the separation gels. The 2-D mobilities of SP3 fractions were quite similar to that of albumin. Family data were consistent with the hypothesis that the observed SP3 phenotypes were controlled by four co-dominant, autosomal alleles (D, F, I, S). Evidence was provided that the F allele can be further divided into two alleles (F1 and F2); the mobilities of F1 and F2 variants were very similar. Each of the SP3 alleles gave rise to one fraction and each of the heterozygous types showed two fractions. More than 600 horses representing five different breeds (Swedish Trotter, North-Swedish Trotter, Thoroughbred, Arab and Polish Tarpan) were typed for SP3, and allele frequency estimates were calculated. SP3 was highly polymorphic in all breeds studied.

  4. Reparation and Immunomodulating Properties of Bacillus sp. Metabolites from Permafrost.

    Science.gov (United States)

    Kalenova, L F; Melnikov, V P; Besedin, I M; Bazhin, A S; Gabdulin, M A; Kolyvanova, S S

    2017-09-01

    An ointment containing metabolites of Bacillus sp. microorganisms isolated from permafrost samples was applied onto the skin wound of BALB/c mice. Metabolites isolated during culturing of Bacillus sp. at 37°C produced a potent therapeutic effect and promoted wound epithelialization by 30% in comparison with the control (ointment base) and by 20% in comparison with Solcoseryl. Treatment with Bacillus sp. metabolites stimulated predominantly humoral immunity, reduced the time of wound contraction and the volume of scar tissue, and promoted complete hair recovery. These metabolites can be considered as modulators of the wound process with predominance of regeneration mechanisms.

  5. Post-neonatal drop in alveolar SP-A expression

    DEFF Research Database (Denmark)

    Stray-Pedersen, Arne; Vege, Ashild; Stray-Pedersen, Asbjorg

    2008-01-01

    BACKGROUND: Surfactant protein A (SP-A) is synthesized in the lung and is a part of the innate immune system. The aim of this study was to evaluate the expression of SP-A in lung tissue from fetuses, infants, children and adults with special regard to sudden infant death syndrome (SIDS). METHODS......: A total of 160 cases were studied; 19 fetuses and neonates, 59 SIDS and 49 explained infant deaths below 1 year of age, 19 toddlers and 14 adults. Immunohistochemical detection of SP-A using monoclonal antibodies was performed by microscopy of lung tissue specimens collected at autopsy. A scoring system...

  6. Efektivitas Ovitrap Bambu terhadap Jumlah Jentik Aedes sp yang Terperangkap

    Directory of Open Access Journals (Sweden)

    Wiwit Aditama

    2015-05-01

    places of 10 subdistricts. Data of trapped Aedes sp larvae numbers was collected four times repeatedly within one week time-lapse. Analysis was conducted using the mean number of larvae in ovitraps and ovitrap index. The number of Aedes sp larvae trapped was 1,265. The most effective ovitrap is piece of bamboo, mean = 123, p value = 0.006, HI = 10.01% (16.66 26.67%, CI = 36.8% (336.06 - 39.74%, BI = 29.97% (73.33 - 103.3%. Health authorities should promote bamboo ovitrap, especially to public as an effort to control Aedes sp.

  7. Späte Mutterschaft – (keine biografische Entscheidung

    Directory of Open Access Journals (Sweden)

    Martina Beham

    2004-11-01

    Full Text Available Der Übergang in die Mutterschaft findet zunehmend später statt. Über die Gründe liegen zahlreiche Vermutungen und einige theoretische Diskussionen, aber kaum empirische Befunde vor. Die Autorinnen möchten mit ihrer Studie einen Beitrag zum Abbau dieses Forschungsdefizits leisten. In ihrer empirisch-biografischen Untersuchung gehen Ingrid Herlyn und Dorothea Krüger der Frage nach, ob späte Erstmutterschaft ein neues biografisches Muster der Familiengründung darstellt oder ob Mutterschaft nach wie vor eine selbstverständlich anerkannte Norm ist, deren Realisierung im Lebenslauf lediglich zeitlich später stattfindet.

  8. Pengaruh Perbedaan Konsentrasi Ekstrak Sargassum sp. dan Lama Penyimpanan terhadap Oksidasi Lemak pada Fillet Ikan Patin (Pangasius sp.

    Directory of Open Access Journals (Sweden)

    Fatin Hidayati

    2017-05-01

    Full Text Available ABSTRAK Ikan patin merupakan ikan air tawar yang mengandung lemak dan protein tinggi sehingga apabila dilakukan penyimpanan rentan terjadi oksidasi yang mengakibatkan ketengikan. Sargassum sp. dengan kandungan fenol dan flavonoid mampu menghambat terjadinya oksidasi pada fillet ikan patin. Penelitian ini bertujuan untuk mengetahui pengaruh perbedaan ekstrak Sargassum sp. dan lama penyimpanan dalam menghambat terjadinya oksidasi pada fillet ikan patin. Materi yang digunakan dalam penelitian ini adalah ekstrak Sargassum sp. dan fillet ikan patin. Metode penelitian yang digunakan adalah experimental laboratories dengan menggunakan Rancangan Acak Lengkap (RAL faktorial dengan 2 faktor yaitu konsentrasi ekstrak Sargassum sp. (0%, 1%, 1,5% dan 2% dan lama penyimpanan (hari ke-0, hari ke-2, hari ke-4, dan hari ke-6. Hasil penelitian menunjukkan bahwa perbedaan penambahan konsentrasi ekstrak Sargassum sp. dan lama penyimpanan memberikan pengaruh nyata terhadap nilai PV, nilai TBA, kadar lemak, kadar protein, kadar air serta organoleptik (P < 0,05. Hasil penelitian tahap I didapatkan rendemen Sargassum sp. dengan pelarut etanol 96% sebesar 1,39%, kandungan fenol 1,813%, flavonoid 0,278% dan aktivitas antioksidan 99,1659 ppm (kuat. Hasil penelitian tahap II didapatkan nilai PV berkisar antara 2,03 - 19,82 meq/kg, nilai TBA 0,63 - 6,72 mg.mal/kg. Konsentrasi 1,5% merupakan konsentrasi terbaik ekstrak Sargassum sp. dalam menghambat oksidasi lemak pada fillet ikan patin selama penyimpanan. Kata kunci: Antioksidan, Ekstrak Sargassum sp., Lama Penyimpanan, Oksidasi lemak, Fillet Ikan patin ABSTRACT Catfish is a freshwater fish that contain high fat and protein so that if its stored it will susceptible to oxidation process which leads to rancidity. Sargassum sp. with its phenolic and flavonoid content are able to inhibit the oxidation process in catfish fillet. This research was aimed to know the effects of different concentrations of Sargassum sp. extracts and

  9. Mycorrhizal dependency of laurel (Ocotea sp.)

    International Nuclear Information System (INIS)

    Sierra-Escobar, Jorge A; Castro Restrepo, Dagoberto; Osorio Vega, Walter

    2009-01-01

    A greenhouse experiment was carried out to determine the mycorrhizal dependency of laurel (>Ocotea sp.). In order to do this, a completely randomized experimental design was used, with six treatments in a factorial array of 3 x 2 and five repetitions. The treatments involved a combination of three Phosphorus (P) levels in soil solution (0.002, 0.02 and 0.2 mg L-1) and two levels of mycorrhizal inoculation, either inoculated or non-inoculated with Glomus aggregatum Schenck and Smith. The leaf P content as a function of time was used as an output variable. Shoot dry matter, shoot P content, mycorrhizal colonization of roots, and mycorrhizal dependence were measured at harvest. The results indicated that the leaf P content increased significantly when using the mycorrhizal inoculation in laurel at P level 0.2 mg L -1, but not in the other P levels, on some of the sampling days. Shoot dry weight and total plant P content did not increase at all levels of soil available P. Mycorrhizal dependency of laurel reached 28%, which allows this species to be classified as moderately dependent on mycorrhiza.

  10. Production of biodiesel from Coelastrella sp. microalgae

    Science.gov (United States)

    Mansur, Dieni; Fitriady, Muhammad Arifuddin; Susilaningsih, Dwi; Simanungkalit, Sabar Pangihutan

    2017-11-01

    Microalgae have a wide area of usage and one of them it can be used for biodiesel production. In biodiesel production, lipids containing triglyceride or free fatty acid are converted into methyl ester through trans/esterification reactions. Lipids from microalgae can be extracted by acetone and dimethyl carbonate using homogenizer. Esterification of the lipids was investigated using various catalysts and source of methyl group. Activity of homogeneous catalyst such as HCl and H2SO4 and heterogeneous catalysts such as montmorillonit K-10 and ledgestone was investigated. Moreover, methanol and dimethyl carbonate as source of methyl group were also studied. Among of catalysts with methanol as source of methyl group, it was found that yield of crude biodiesel derived from Choelestrella Sp. microalgae was high over H2SO4 catalyst. On the other hand, over H2SO4 catalyst using dimethyl carbonate as source of methyl group, yield of crude biodiesel significant increase. However, FAME composition of crude biodiesel was high over HCl catalyst.

  11. Campylobacter iguaniorum sp. nov., isolated from reptiles.

    Science.gov (United States)

    Gilbert, Maarten J; Kik, Marja; Miller, William G; Duim, Birgitta; Wagenaar, Jaap A

    2015-03-01

    During sampling of reptiles for members of the class Epsilonproteobacteria, strains representing a member of the genus Campylobacter not belonging to any of the established taxa were isolated from lizards and chelonians. Initial amplified fragment length polymorphism, PCR and 16S rRNA sequence analysis showed that these strains were most closely related to Campylobacter fetus and Campylobacter hyointestinalis. A polyphasic study was undertaken to determine the taxonomic position of five strains. The strains were characterized by 16S rRNA and atpA sequence analysis, matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry and conventional phenotypic testing. Whole-genome sequences were determined for strains 1485E(T) and 2463D, and the average nucleotide and amino acid identities were determined for these strains. The strains formed a robust phylogenetic clade, divergent from all other species of the genus Campylobacter. In contrast to most currently known members of the genus Campylobacter, the strains showed growth at ambient temperatures, which might be an adaptation to their reptilian hosts. The results of this study clearly show that these strains isolated from reptiles represent a novel species within the genus Campylobacter, for which the name Campylobacter iguaniorum sp. nov. is proposed. The type strain is 1485E(T) ( = LMG 28143(T) = CCUG 66346(T)). © 2015 IUMS.

  12. Parapedobacter koreensis gen. nov., sp. nov.

    Science.gov (United States)

    Kim, Myung Kyum; Na, Ju-Ryun; Cho, Dong Ha; Soung, Nak-Kyun; Yang, Deok-Chun

    2007-06-01

    Strain Jip14(T), a Gram-negative, non-spore-forming, rod-shaped, non-motile bacterium, was isolated from dried rice straw and characterized in order to determine its taxonomic position. 16S rRNA gene sequence analysis revealed that strain Jip14(T) belongs to the family Sphingobacteriaceae, and the highest degree of sequence similarity was determined to be to Pedobacter saltans DSM 12145(T) (88.5 %), Pedobacter africanus DSM 12126(T) (87.6 %), Pedobacter heparinus DSM 2366(T) (87.1 %) and Pedobacter caeni LMG 22862(T) (86.9 %). Chemotaxonomic data revealed that strain Jip14(T) possesses menaquinone MK-7 and the predominant fatty acids C(15 : 0) iso, C(16 : 0), C(16 : 0) 10-methyl, C(17 : 0) iso 3-OH and summed feature 3 (C(15 : 0) iso 2-OH/C(16 : 1)omega7c). The results of physiological and biochemical tests clearly demonstrated that strain Jip14(T) represents a distinct species. Based on these data, Jip14(T) should be classified within a novel genus and species, for which the name Parapedobacter koreensis gen. nov., sp. nov. is proposed. The type strain of Parapedobacter koreensis is Jip14(T) (=KCTC 12643(T)=LMG 23493(T)).

  13. Pedobacter insulae sp. nov., isolated from soil.

    Science.gov (United States)

    Yoon, Jung-Hoon; Kang, So-Jung; Oh, Hyun Woo; Oh, Tae-Kwang

    2007-09-01

    A Gram-negative, non-motile, rod-shaped bacterium, DS-139(T), was isolated from a soil sample collected from Dokdo, Korea, and subjected to a polyphasic taxonomic analysis. Strain DS-139(T) grew optimally at 25 degrees C and pH 6.5-7.5 in the presence of 0-0.5 % (w/v) NaCl. It contained MK-7 as the predominant menaquinone and iso-C(15 : 0), C(16 : 1)omega7c and/or iso-C(15 : 0) 2-OH and iso-C(17 : 0) 3-OH as the major fatty acids. The DNA G+C content was 39.4 mol%. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain DS-39(T) belongs to the genus Pedobacter in the family Sphingobacteriaceae. The similarity values between the 16S rRNA gene sequence of strain DS-139(T) and those of the type strains of recognized Pedobacter species, except Pedobacter saltans, were in the range 93.9-96.7 %. The differential phenotypic properties, together with the phylogenetic distinctiveness, were sufficient to assign strain DS-139(T) to a species that is separate from recognized Pedobacter species. On the basis of the phenotypic and phylogenetic data, therefore, strain DS-139(T) represents a novel species of the genus Pedobacter, for which the name Pedobacter insulae sp. nov. is proposed. The type strain is DS-139(T) (=KCTC 12820(T) =DSM 18684(T)).

  14. Lactobacillus paralimentarius sp. nov., isolated from sourdough.

    Science.gov (United States)

    Cai, Y; Okada, H; Mori, H; Benno, Y; Nakase, T

    1999-10-01

    Six strains of lactic acid bacteria isolated from sourdough were characterized taxonomically. They were Gram-positive, catalase-negative, facultatively anaerobic rods that did not produce gas from glucose. Morphological and physiological data indicated that the strains belong to the genus Lactobacillus and they were similar to Lactobacillus alimentarius in phenotypic characteristics. These strains shared the same phenotypic characteristics and exhibited intragroup DNA homology values of over 89.8%, indicating that they comprised a single species. The G + C content of the DNA for the strains was 37.2-38.0 mol%. The 16S rRNA sequence of representative strain TB 1T was determined and aligned with that of other Lactobacillus species. This strain was placed in the genus Lactobacillus on the basis of phylogenetic analysis. L. alimentarius was the most closely related species in the phylogenetic tree and this species also showed the highest sequence homology value (96%) with strain TB 1T. DNA-DNA hybridization indicated that strain TB 1T did not belong to L. alimentarius. It is proposed that these strains are placed in the genus Lactobacillus as a new species, Lactobacillus paralimentarius sp. nov. The type strain of L. paralimentarius is TB 1T, which has been deposited in the Japan Collection of Microorganisms (JCM) as strain JCM 10415T.

  15. sp magnetism in clusters of gold thiolates

    International Nuclear Information System (INIS)

    Ayuela, A; Hernando, A; Echenique, P M; Crespo, P; García, M A

    2012-01-01

    Using first-principles calculations, we consider the bond between thiolate and small Au clusters, with particular emphasis on the resulting magnetic moment. The moment of pure gold clusters is 1 μ B for clusters with an odd number of Au atoms and zero for those with an even number. The addition of the thiolate, having an odd number of electrons itself, shifts the phase of the odd-even oscillations so that particles with an even number of Au atoms now have unit moment. Surprisingly, gold thiolate exhibits a dramatic and non-intuitive distribution of charge and spin moment. Our results show that the S-Au bond is such that sulfur does not get charge and an electron is transferred to the Au cluster. This extra electron is mainly sp in character and resides in an electronic shell below the Au surface. The calculations suggest that any thiolate-induced magnetism occurs in the gold nanoparticle and not the thiolate, and can be controlled by modifying the thiolate coverage. (paper)

  16. Preliminary SP-100/Stirling heat exchanger designs

    International Nuclear Information System (INIS)

    Schmitz, P.; Tower, L.; Blue, B.; Dunn, P.

    1994-01-01

    Analytic modeling of several heat exchanger concepts to couple the SP-100 nuclear reactor lithium loop and the Space Stirling Power Convertor (SSPC) was performed. Four 25 kWe SSPC's are used to produce the required 100 kW of electrical power. This design work focused on the interface between a single SSPC and the primary lithium loop. Manifolding to separate and collect the four channel flow was not modeled. This work modeled two separate types of heat exchanger interfaces (conductive coupling and radiative coupling) to explore their relative advantages and disadvantages. The minimum mass design of the conductively coupled concepts was 18 kg or 0.73 kg/kWe for a single 25 kWe convertor. The minimum mass radiatively coupled concept was 41 kg or 1.64 kg/kWe. The direct conduction heat exchanger provides a lighter weight system because of its ability to operate the Stirling convertor evaporator at higher heat fluxes than those attainable by the radiatively coupled systems. Additionally the conductively coupled concepts had relatively small volumes and provide potentially simpler assembly. Their disadvantages were the tight tolerances and material joining problems associated with this refractory to superalloy interface. The advantages of the radiatively coupled designs were the minimal material interface problems

  17. The Growth of Monoraphidium sp. and Scenedesmus sp. Cells in the Presence of Thorium

    Directory of Open Access Journals (Sweden)

    Juliana Cristina de Queiroz

    2012-01-01

    Full Text Available Toxicity of thorium by Monoraphidium sp. and Scenedesmus sp. was studied. Microalgal cultures were inoculated in ASM-1 medium in presence and absence of thorium. Its effect was monitored by direct counting on Fuchs-Rosenthal chamber and with software. The toxicity of thorium over the species was observed for concentrations over 50.0 mg/L. After 30 days, Monoraphidium cells decreased their concentration from 4.23×106 to 4.27×105 and 8.57×105 cells/mL, in the presence of 50.0 and 100.0 mg/L of thorium, respectively. Scenedesmus sp. cells were more resistant to thorium: for an initial cell concentration of 7.65×104 cells/mL it was observed a change to 5.25×105 and 5.12×105 cells/mL, in the presence of thorium at 50.0 and 100.0 mg/L, respectively. This is an indication that low concentrations of the radionuclide favored the growth, and that Scenedesmus cells are more resistant to thorium than Monoraphidium cells. The software used for comparison with direct count method proved to be useful for the improvement of accuracy of the results obtained, a decrease in the uncertainty and allowed recording of the data. The presence of thorium suggests that low concentrations have a positive effect on the growth, due to the presence of the nitrate, indicating its potential for ecotoxicological studies.

  18. The Growth of Monoraphidium sp. and Scenedesmus sp. Cells in the Presence of Thorium

    Science.gov (United States)

    de Queiroz, Juliana Cristina; Ferreira, Ana Cristina de Melo; da Costa, Antonio Carlos Augusto

    2012-01-01

    Toxicity of thorium by Monoraphidium sp. and Scenedesmus sp. was studied. Microalgal cultures were inoculated in ASM-1 medium in presence and absence of thorium. Its effect was monitored by direct counting on Fuchs-Rosenthal chamber and with software. The toxicity of thorium over the species was observed for concentrations over 50.0 mg/L. After 30 days, Monoraphidium cells decreased their concentration from 4.23 × 106 to 4.27 × 105 and 8.57 × 105 cells/mL, in the presence of 50.0 and 100.0 mg/L of thorium, respectively. Scenedesmus sp. cells were more resistant to thorium: for an initial cell concentration of 7.65 × 104 cells/mL it was observed a change to 5.25 × 105 and 5.12 × 105 cells/mL, in the presence of thorium at 50.0 and 100.0 mg/L, respectively. This is an indication that low concentrations of the radionuclide favored the growth, and that Scenedesmus cells are more resistant to thorium than Monoraphidium cells. The software used for comparison with direct count method proved to be useful for the improvement of accuracy of the results obtained, a decrease in the uncertainty and allowed recording of the data. The presence of thorium suggests that low concentrations have a positive effect on the growth, due to the presence of the nitrate, indicating its potential for ecotoxicological studies. PMID:22649297

  19. Down-regulation of human topoisomerase IIα expression correlates with relative amounts of specificity factors Sp1 and Sp3 bound at proximal and distal promoter regions

    Directory of Open Access Journals (Sweden)

    Isaacs Richard J

    2007-05-01

    Full Text Available Abstract Background Topoisomerase IIα has been shown to be down-regulated in doxorubicin-resistant cell lines. The specificity proteins Sp1 and Sp3 have been implicated in regulation of topoisomerase IIα transcription, although the mechanism by which they regulate expression is not fully understood. Sp1 has been shown to bind specifically to both proximal and distal GC elements of the human topoisomerase IIα promoter in vitro, while Sp3 binds only to the distal GC element unless additional flanking sequences are included. While Sp1 is thought to be an activator of human topoisomerase IIα, the functional significance of Sp3 binding is not known. Therefore, we sought to determine the functional relationship between Sp1 and Sp3 binding to the topoisomerase IIα promoter in vivo. We investigated endogenous levels of Sp1, Sp3 and topoisomerase IIα as well as binding of both Sp1 and Sp3 to the GC boxes of the topoisomerase IIα promoter in breast cancer cell lines in vivo after short term doxorubicin exposure. Results Functional effects of Sp1 and Sp3 were studied using transient cotransfection assays using a topoisomerase IIα promoter reporter construct. The in vivo interactions of Sp1 and Sp3 with the GC elements of the topoisomerase IIα promoter were studied in doxorubicin-treated breast cancer cell lines using chromatin immunoprecipitation assays. Relative amounts of endogenous proteins were measured using immunoblotting. In vivo DNA looping mediated by proteins bound at the GC1 and GC2 elements was studied using the chromatin conformation capture assay. Both Sp1 and Sp3 bound to the GC1 and GC2 regions. Sp1 and Sp3 were transcriptional activators and repressors respectively, with Sp3 repression being dominant over Sp1-mediated activation. The GC1 and GC2 elements are linked in vivo to form a loop, thus bringing distal regulatory elements and their cognate transcription factors into close proximity with the transcription start site

  20. Cloning and expression of an amylase gene from Bacillus sp ...

    African Journals Online (AJOL)

    SAM

    2014-08-06

    Aug 6, 2014 ... Bacillus sp. isolated from an agricultural field in West. Bengal, India ... plants, even though, the competition is incipient (Sen,. 2007), and therefore ..... proteins: Engineering mesophilic–like activity and stability in a cold adapted ...