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1.
Through the use of an enrichment technique, we isolated from the agricultural soils of Morelos in central México a strain of Burkholderia zhejiangensis identified as CEIB S4-3, it’s could use the pesticide methyl parathion (MP) as the only source of carbon and degrade completely p-nitrophenol (PNP). For more efficient MP and PNP degradation by the CEIB S4-3 strain, the absence of an extra carbon source, a large inoculum and an MP concentration up to 50 mg/l are required. Sequence and annotation analysis of the draft genome, showed presence of mpd functional gene, which was expressed and its activity on the MP was confirmed. Additionally, the genes coding for enzymes in the benzoquinone pathway (conducted by Gram-negative bacteria) and the benzenotriol pathway (conducted by Gram-positive bacteria) were found, which was corroborated by identification of intermediary metabolites by HPLC. Thus, we propose that B. zhejiangensis CEIB S4-3 uses both degradation pathways.  相似文献   

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Glutaredoxins are a family of small molecular weight proteins that have a central role in cellular redox regulation. Human GRX1 (hGRX1) has also been shown to play an integral role in copper homeostasis by regulating the redox activity of the metalated sites of copper chaperones such as ATOX1 and SOD1, and the copper efflux proteins ATP7A and ATP7B. To further elucidate the role of hGRX1 in copper homeostasis, we examined the impact of RNA interference-mediated knockdown of CG6852, a putative Drosophila orthologue of hGRX1. CG6852 shares ~41 % amino acid identity with hGRX1 and key functional domains including the metal-binding CXXC motif are conserved between the two proteins. Knockdown of CG6852 in the adult midline caused a thoracic cleft and reduced scutellum, phenotypes that were exacerbated by additional knockdown of copper uptake transporters Ctr1A and Ctr1B. Knockdown of CG6852 in the adult eye enhanced a copper-deficiency phenotype caused by Ctr1A knockdown while ubiquitous knockdown of CG6852 resulted a mild systemic copper deficiency. Therefore we conclude that CG6852 is a putative orthologue of hGRX1 and may play an important role in Drosophila copper homeostasis.  相似文献   

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The vacuolar H+-pyrophosphatase (V-PPase) is an electrogenic H+ pump localized in the plant vacuolar membrane. V-PPase from many species has been characterized previously and the corresponding genes/cDNAs have been cloned. Cloning of the V-PPase genes from many plant species has revealed conserved motifs that may correspond to catalytic sites. The completion of the entire DNA sequence of Oryza sativa (430 Mb) presented an opportunity to study the structure and function of V-PPase proteins, and also to identify new members of this family in Oryza sativa. Our analysis identified three novel V-PPase proteins in the Oryza sativa genome that contain functional domains typical of V-PPase. We have designated them as OVP3 to OVP5. The new predicted OVPs have chromosomal locations different from previously characterized V-PPases (OVP1 and OVP2) located on chromosome 6. They all contain three characteristic motifs of V-PPase and also a conserved motif [DE]YYTS, specific to type I V-PPases and involved in coupling PPi hydrolysis to H+ translocation.  相似文献   

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Late embryogenesis abundant (LEA) proteins are identified as a large and highly diverse group of polypeptides accumulating in response to cellular dehydration in many organisms. However, there are only very limited reports of this protein family in maize until this study. In the present paper, we identified 32 LEA genes in maize. A total of 83 LEA proteins including 51 members in Arabidopsis and 32 putative members in maize were classified into nine groups. Gene organization and motif compositions of the LEA members are highly conserved in each of the groups, indicative of their functional conservation. The predicted ZmLEA genes were non-random distributed across chromosomes, and transposition event and segmental duplication contributed to the expansion of the LEA gene family in maize. Some abiotic stress-responsive cis-elements were also found in the promoters of ZmLEA genes. Microarray expression analyses revealed different accumulation patterns of ZmLEA family members. Moreover, some members of ZmLEAs were regulated under IAA and some abiotic stresses. This study will provide comprehensive information for maize LEA gene family and may pave the way for deciphering their functions in further studies.  相似文献   

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Sublethal concentrations of chemical insecticides may cause changes in some behavioral characteristics of natural enemies such as functional responses. The residual effect of three synthetic insecticides including deltamethrin, fenvalerate and azadirachtin were studied on functional response of Habrobracon hebetor Say to Ephestia kuehniella Zeller larvae. Seven host densities (2, 4, 8, 16, 32, 64 and 96) were used during a 24 h period. The resulting data were appropriately fit to Type II functional response models in all treatments: (1) control (0.0916 h?1; and T h  = 0.2011 h); (2) deltamethrin (a = 0.0839 h?1; and T h  = 0.3560 h); (3) fenvalerate (a = 0.0808 h?1 and T h  = 0.3623 h); and (4) azadirachtin (a = 0.0900 h?1 and T h  = 0.2042 h). Maximum theoretical parasitism rate (T/T h ) was 119.34 estimated for control wasps. There was no significant difference between the values of attack rates (a and a + D a ) in all treatments while the handling time was statistically affected in female wasps treated with fenvalerate. Our findings will be useful in safe application of these insecticides in pest management programmes.  相似文献   

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Diacylglycerol kinase (DGK) is a kind of phosphokinase that catalyzes the formation of signaling molecule phosphatidic acid. In this study, seven maize (Zea mays) DGK gene family members were identified by an exploration of maize genome via multiple online databases, and designated as ZmDGK1-7, respectively. The proteins encoded by ZmDGKs ranged from 487 to 716 amino acids, and had a molecular weight (MWs) between 54.6 and 80.2 kDa. Phylogenetic analysis revealed that ZmDGKs grouped into three clusters as described for known plant DGK families: Cluster I was composed of three maize DGKs, ZmDGK1, ZmDGK4 and ZmDGK5, cluster II contained ZmDGK6, and the isoforms ZmDGK2, ZmDGK3 and ZmDGK7 fell into cluster III. ZmDGK proteins featured the typical functional domains, while all seven ZmDGKs have a conserved catalytic domain DGKc, only the cluster I ZmDGKs have the DAG/PE binding domain. Most ZmDGK genes showed ubiquitous expression profiles at various developmental stages, while a high relative expression was observed at the tasseling stage. ZmDGK genes exhibited differential expression patterns in response to abiotic stresses including cold, salinity and drought, and all ZmDGK genes were found obviously up-regulated by cold. The distinct roles of ZmDGKs in cold response was also supported by the finding that an accumulation of DGK products–PA under low temperature. This study will help to better understand the roles of DGKs in the development and abiotic stress responses in major crops.  相似文献   

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The objective of this study was to determine the occurrence and distribution of antibiotic resistant (AR) lactic acid bacteria (LAB) in Indian poultry. LAB from poultry farm feces (n = 21) and samples from slaughter houses comprising chicken intestine (n = 46), raw meat (n = 23), and sanitary water (n = 4) were evaluated and compared with those from organic chicken (OC) collected from nearby villages. Screening studies showed 5–7 log units higher erythromycin (ER), tetracycline (TC) and vancomycin (VAN) resistant LAB from conventional poultry chicken (CC) compared to OC. Molecular characterization of isolated cultures (n = 32) with repetitive-PCR profiling and 16S rRNA gene sequencing revealed their taxonomical status as Enterococcus faecium (n = 16), Enterococcus durans (n = 2), Lactobacillus plantarum (n = 10), Lactobacillus pentosus (n = 1) and Lactobacillus salivarius (n = 3). The isolates were found to harbor erm(B), msr(C), msr(A/B), tet(M), tet(L) and tet(K) genes associated with Tn916 and Tn917 family transposons. Expression studies through real-time PCR revealed antibiotic-induced expression of the identified AR genes. In vitro and in vivo conjugational studies revealed transfer of ER and TC resistant (ERR and TCR) genes with transfer frequencies of 10?7 and 10?4 transconjugants recipient?1, respectively. Although no known VAN resistance (VANR) genes were detected, high phenotypic resistance was observed and was transferable to the recipient. From a public health point of view, this study reports Indian poultry as a major source of high levels of AR bacteria contaminating the food chain and the environment. Thus, urgent and determined strategies are needed to control the spread of multiple AR bacteria.  相似文献   

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Many phytopathogenic micro-organisms such as bacteria and fungi produce pectin methylesterases (PME) during plant invasion. Plants and insects also produce PME to degrade plant cell wall. In the present study, a thermostable pectin methylesterase (CtPME) from Clostridium thermocellum belonging to family 8 carbohydrate esterase (CE8) was cloned, expressed and purified. The amino acid sequence of CtPME exhibited similarity with pectin methylesterase from Erwinia chrysanthemi with 38% identity. The gene encoding CtPME was cloned into pET28a(+) vector and expressed using Escherichia coli BL21(DE3) cells. The recombinant CtPME expressed as a soluble protein and exhibited a single band of molecular mass approximately 35.2 kDa on SDS-PAGE gels. The molecular mass, 35.5 kDa of the enzyme, was also confirmed by MALDI-TOF MS analysis. Notably, highest protein concentration (11.4 mg/mL) of CtPME was achieved in auto-induction medium, as compared with LB medium (1.5 mg/mL). CtPME showed maximum activity (18.1 U/mg) against citrus pectin with >85% methyl esterification. The optimum pH and temperature for activity of CtPME were 8.5 and 50 °C, respectively. The enzyme was stable in pH range 8.0–9.0 and thermostable between 45 and 70 °C. CtPME activity was increased by 40% by 5 mM Ca2+ or Mg2+ ions. Protein melting curve of CtPME gave a peak at 80 °C. The peak was shifted to 85 °C in the presence of 5 mM Ca2+ ions, and the addition of 5 mM EDTA shifted back the melting peak to 80 °C. CtPME can be potentially used in food and textile industry applications.  相似文献   

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Sulfur is an essential element for all living organisms. Plants can convert inorganic sulfur into organic sulfur compounds by complex enzymatic steps. In this study, we conducted a genome-wide analysis of sulfate transporter genes (SULTRs) in the sorghum (Sorghum bicolor) genome and examined expression profiles of SbSULTR genes under 200 µM cadmium (Cd) exposure. As a result of sorghum genome analysis, 11 SULTR genes were identified, including SbSULTR1;1, SbSULTR1;2, SbSULTR1;3, SbSULTR2;1, SbSULTR2;2, SbSULTR3;1, SbSULTR3;2, SbSULTR3;3, SbSULTR3;4, SbSULTR3;5, and SbSULTR4. Given names are based on phylogeny and chromosomal locations. Except SbSULTR4, all SbSULTR proteins contained Sulfate_transp (PF00916), STAS (PF01740) domains and 12 trans-membrane domains. Phylogenetic analysis revealed that four major groups were identified such as SULTR1, 2, 3, and 4 groups and SULTR4 group was separated to other SULTR groups. In promotor sequences of SbSULTR genes, many diverse cis-acting elements were found mainly related with physiological processes such as light, stress and hormone responsiveness. The expression profiles of SbSULTR genes showed that SULTR1;2, 1;3, 3;3, and 3;5 genes up-regulated in root, while expression level of SULTR4 decreased under 200 µM Cd exposure. The predicted 3D structures of SULTR proteins showed some conformational changes, suggesting functional diversities of SbSULTRs. Finally, results of this study may contribute towards understanding SbSULTR genes and their regulations and roles in Cd stress in sorghum.  相似文献   

12.
Trichocysts are a common cell organelle of ciliates and dinoflagellates. They are composed of trichocyst matrix proteins and have been intensely investigated and characterized in ciliates. Here, for the first time, data have been obtained for trichocyst matrix proteins of a dinoflagellate. A DELTA-BLAST search using 14 available and complete amino acid sequences of mature trichocyst matrix proteins of the ciliate Paramecium tetraurelia resulted in 16 hits for the dinoflagellate Oxyrrhis marina when the E values and bit values to be scored were <10?4 and >40. They code for proteins with acidic pI values and exceeded the precursors of the trichocyst matrix proteins of the ciliate approximately twofold in length. The values calculated for coverage, identity, and positives ranged from 76 to 100, 21.5 to 28.3, and 44.9 to 53.9%, respectively. Protein conformation predictions indicate coiled-coil domains which are a common feature of mature ciliate trichocyst matrix proteins. As often several EST sequences of O. marina matched with a queried mature trichocyst matrix protein of P. tetraurelia, a multigene family can be assumed for trichocyst proteins in this dinophyte, too. Trichocyst-enriched fractions of O. marina were isolated and subjected to sodium dodecyl sulfate polyacrylamide gel electrophoresis. When samples were incubated with loading buffer without a reducing agent, the banding pattern was mainly composed of three regions in the range of >90, 75–60, and 50–35 kDa, with each region consisting of four to five bands. Tryptic in gel digestion of proteins excised from these three gel regions followed by mass spectrometry confirmed that up to 14 of the 16 predicted proteins were present within the trichocyst-enriched fractions. When the samples were reduced with either ß-mercaptoethanol or dithiothreitol, the proteins of the three regions disappeared almost completely and proteins in the range of 27 to 15 kDa became the dominating bands. Up to 12 of the predicted proteins were detected within these bands.  相似文献   

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A Gram-stain negative, facultative anaerobic, non-motile, strongly orange-pigmented and rod-shaped bacterium, designated XAY3209T, was isolated from a marine sediment sample collected from the coast of Weihai, China. Strain XAY3209T was found to grow optimally at 30 °C, at pH 7.0 and in the presence of 2.0% (w/v) NaCl. Its genomic DNA G+C content was 41.9 mol%. On the basis of 16S rRNA gene sequence similarity, the novel isolate belongs to the family Cyclobacteriaceae and is related to the genus Algoriphagus. It shares 98.1% 16S rRNA sequence identity with Algoriphagus marincola, its close phylogenetic relative, but did not show similarities more than 97% with other members of the genus Algoriphagus with validly published names. It contained menaquinone-7 (MK-7) as the sole respiratory quinone, iso-C15:0, iso-C17:1 ω9c and Summed feature 3 (C16:1 ω7c and/or iso-C15:0 2-OH) as the major fatty acids. The major polar lipids were phosphatidylethanolamine, one unidentified aminolipid, one unidentified phospholipid and five unidentified lipids. Results of physiological experiments, biochemical tests and genome average nucleotide identity value (with A. marincola MCCC 1F01203T) indicate that strain XAY3209T is genetically and phenotypically distinct from the species of the genus Algoriphagus with validly published names. Strain XAY3209T therefore represents a novel species, for which the name Algoriphagus formosus sp. nov. is proposed. The type strain is XAY3209T (= KCTC 52842T = MCCC 1H00189T).  相似文献   

14.
Border cell (BC) migration during Drosophila oogenesis is an excellent model for the analysis of the migratory and invasive cell behavior. Most studies on BC migration have exploited a slbo-Gal4 driver to regulate gene expression in these cells or to mark them. Here, we report that the slbo-Gal4 transgene present in the line #6458 from the Bloomington Stock Center is inserted within chickadee (chic), a gene encoding the actin-binding protein Profilin, which promotes actin polymerization and is known to be involved in cell migration. The chic6458 mutation caused by the transgene insertion behaves as a null chic allele and is homozygous lethal. To evaluate possible effects of chic6458 on the assessment of BC behavior, we generated new lines bearing the slbo-Gal4 transgene inserted into different second chromosome loci that do not appear to be involved in cell migration. Using these new lines and the slbo-Gal4-chic6458 line, we defined the functional relationships between the twinfilin (twf) and chic in BC migration. Migration of BCs is substantially reduced by mutations in twf, which encodes an actin-binding protein that inhibits actin filament assembly. The defects caused by twf mutations are significantly suppressed when the slbo-Gal4-chic6458, but not the new slbo-Gal4 drivers were used. These findings indicate twf and chic interact and function antagonistically during BC migration in Drosophila oogenesis.  相似文献   

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Sixteen yeast isolates identified as belonging to the genus Sugiyamaella were studied in relation to D-xylose fermentation, xylitol production, and xylanase activities. The yeasts were recovered from rotting wood and sugarcane bagasse samples in different Brazilian regions. Sequence analyses of the internal transcribed spacer (ITS) region and the D1/D2 domains of large subunit rRNA gene showed that these isolates belong to seven new species. The species are described here as Sugiyamaella ayubii f.a., sp. nov. (UFMG-CM-Y607T = CBS 14108T), Sugiyamaella bahiana f.a., sp. nov. (UFMG-CM-Y304T = CBS 13474T), Sugiyamaella bonitensis f.a., sp. nov. (UFMG-CM-Y608T = CBS 14270T), Sugiyamaella carassensis f.a., sp. nov. (UFMG-CM-Y606T = CBS 14107T), Sugiyamaella ligni f.a., sp. nov. (UFMG-CM-Y295T = CBS 13482T), Sugiyamaella valenteae f.a., sp. nov. (UFMG-CM-Y609T = CBS 14109T) and Sugiyamaella xylolytica f.a., sp. nov. (UFMG-CM-Y348T = CBS 13493T). Strains of the described species S. boreocaroliniensis, S. lignohabitans, S. novakii and S. xylanicola, isolated from rotting wood of Brazilian ecosystems, were also compared for traits relevant to xylose metabolism. S. valenteae sp. nov., S. xylolytica sp. nov., S. bahiana sp. nov., S. bonitensis sp. nov., S. boreocarolinensis, S. lignohabitans and S. xylanicola were able to ferment d-xylose to ethanol. Xylitol production was observed for all Sugiyamaella species studied, except for S. ayubii sp. nov. All species studied showed xylanolytic activity, with S. xylanicola, S. lignohabitans and S. valenteae sp. nov. having the highest values. Our results suggest these Sugiyamaella species have good potential for biotechnological applications.  相似文献   

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Acorus calamus Linn. of the family Araceae (Acoraceae), commonly known as Sweet Flag and Vacha. The rhizome of this plant has medicinal properties against bugs, moths, lice and emetic stomach in dyspepsia. Chemical composition of the hydro-distilled essential oil obtained from the rhizomes of A. calamus was analyzed by gas chromatography equipped with flame ionization detector and gas chromatography coupled with mass spectrometry. The essential oil of A. calamus and its major compound β-asarone were tested against five Gram-positive, eight Gram-negative bacteria, and three fungi by the tube-dilution method at a concentration rang of 5.0–0.009 mg/mL. Forty constituents were identified which comprised 98.3 % of the total oil. The major compound β-asarone (80.6 %) was identified and confirm by NMR (1H– & 13C–) in rhizome oil of A. calamus. The organism Micrococcus luteus was found to be more susceptible to the oil with minimum bactericidal concentration (MBC) value of 0.032 ± 0.004 mg/mL, followed by Aspergillus fumigatus, Aspergillus niger and Micrococcus flavus with MBC values of 0.104 ± 0.016, 0.117 ± 0.017 and 0.143 ± 0.013 mg/mL, respectively. The compound β-asarone was susceptible to the microorganism A. niger with MBC value 0.416 ± 0.065 mg/mL. The present study revealed that tetraploid variety of A. calamus is growing in this region with substantial amount of β-asarone. The oil showed bactericidal property against tested bacteria and fungi. The β-asarone exhibited poorer bactericidal activity against test microorganisms.  相似文献   

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A Gram staining negative, rod-shaped, aerobic bacterial strain J5-3T with a single polar flagellum was isolated from coking wastewater collected from Shaoguan, Guangdong, China. It was motile and capable of optimal growth at pH 6–8, 30 °C, and 0–2 % (w/v) NaCl. Its predominant fatty acids were 11-methyl C18:1 ω7c (29.2 %), C16:0 (20.6 %), C19:0 cyclo ω8c (18.2 %), C18:0 (11.0 %), and C18:1 ω7c/C18:1 ω6c (10.9 %) when grown on trypticase soy agar. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, two unknown glycolipids (GL1, GL2), and two unknown phospholipid (PL1, PL2). The predominant ubiquinone was Q-10, and the genome DNA G+C content was 61.7 mol %. Phylogenetic analysis based on the 16S rRNA gene sequences indicated that strain J5-3T belonged to the family Hyphomicrobiaceae in Alphaproteobacteria. It shared the 16S rRNA gene sequence similarities of 93.8–96.1 % with the genus Devosia, 94.5–94.8 % with the genus Pelagibacterium, and <92.0 % with all the other type strains in family Hyphomicrobiaceae. It can be distinguished from the closest phylogenetic neighbors based on several phenotypic and genotypic features, including α-galactosidase activity, tetracycline susceptibility, major fatty acid composition, polar lipid profile, DNA gyrase B subunit (gyrB) gene sequence, and random-amplified polymorphic DNA profile. Therefore, we consider strain J5-3T to represent a novel species of a novel genus within the family Hyphomicrobiaceae, for which the name Paradevosia shaoguanensis gen. nov., sp. nov. is proposed. The type strain of Paradevosia shaoguanensis is J5-3T (=CGMCC 1.12430T =LMG 27409T).  相似文献   

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