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Six Clostridium strains which ferment glycerol to 1,3-propanediol were tested for their taxonomic and phylogenetic relatedness. All but one were known as C butyricum. By physiological tests, 16S rDNA sequences and fatty acid composition two groups were distinguished. The first comprised the strains VPI 3266, DSM 2478 and DSM 523 (C. \"kainantoi\") and was consistent with the type strain of C. butyricum in almost all characters. The second group comprising the strains DSM 5430, DSM 5431 and E5 was related to C. beijerinckii. The 16S rDNAs of these strains were almost identical with that of the type strain of C. beijerinckii, DSM 791. The DNA-DNA hybridization value of DSM 5431 and ES with C. beijerinckii DSM 791 was markedly but not decisively lower (67 and 72%, respectively). However, there were significant physiological differences to C. beijerinckii which suggested to describe the strains as a separate species, Clostridium diolis with strain SH1 (= DSM 5431) as the type strain. The new species is distinguished from C. beijerinckii, which requires complex nutrients, by its ability to grow in glucose mineral medium with biotin as the only growth factor and by differences in substrate utilization. \"C. kainantoi\" Takeda and Matsui was recognized as a later synonym of C. butyricum.  相似文献   

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Strain BBS, the purple sulfur bacterium assigned initially to the species Thiocapsa roseopersicina, is the best studied representative of this species. However, no molecular phylogenetic analysis has been performed to confirm its systematic position. Based on the results of analysis of the sequences of 16S rRNA, cbbL, and nifH genes, DNA-DNA hybridization with the T. roseopersicina type strain, and comparative analysis of the phenotypic characteristics of various species belonging to the genus Thiocapsa, we suggest that strain BBS should be assigned to a new species of the genus Thiocapsa, Thiocapsa bogorovii sp. nov. Original Russian Text ? T.P. Tourova, O.I. Keppen, O.L. Kovaleva, N.V. Slobodova, I.A. Berg, R.N. Ivanovsky, 2009, published in Mikrobiologiya, 2009, Vol. 78, No. 3, pp. 381–392.  相似文献   

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This work deals with the taxonomic study of orange-pigmented bacteria isolated from permafrost sediments, rice plots, and soils contaminated with wastes from the chemical and salt industries that were assigned to the genus Brevibacterium on the basis of phenotypic characteristics, as well as of some strains described previously as Brevibacterium linens. The study revealed three genomic species, whose members and the type strains of the closest species of Brevibacterium had DNA similarity levels between 24 and 59%. The strains of the genomic species differed from each other and from the known species of Brevibacterium in some physiological and biochemical characteristics, as well as in the sugar and polyol composition of their teichoic acids. The 16S rDNA sequence analysis confirmed the assignment of the environmental isolates to the genus Brevibacterium and showed the phylogenetic distinction of the three genomic species. The results obtained in this study allow three new Brevibacterium species to be described: Brevibacterium antiquum (type strain VKM Ac-2118T = UCM Ac-411T), Brevibacterium aurantiacum (type strain VKM Ac-2111T = NCDO 739T = ATCC 9175T), and Brevibacterium permense (type strain VKM Ac-2280T = UCM Ac-413T).  相似文献   

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Four Aeromonas strains (S1.2T, EO-0505, TC1 and TI 1.1) isolated from moribund fish in Spain showed a restriction fragment length polymorphism (RFLP) pattern related to strains of Aeromonas salmonicida and Aeromonas bestiarum but their specific taxonomic position was unclear. Multilocus sequence analysis (MLSA) of housekeeping genes rpoD, gyrB, recA and dnaJ confirmed the allocation of these isolates to an unknown genetic lineage within the genus Aeromonas with A. salmonicida, A. bestiarum and Aeromonas popoffii as the phylogenetically nearest neighbours. Furthermore, a strain biochemically labelled as Aeromonas hydrophila (AH-3), showing a pattern of A. bestiarum based on 16S rDNA-RFLP, also clustered with the unknown genetic lineage. The genes rpoD and gyrB proved to be the best phylogenetic markers for differentiating these isolates from their neighbouring species. Useful phenotypic features for differentiating the novel species from other known Aeromonas species included their ability to hydrolyze elastin, produce acid from l-arabinose and salicin, and their inability to produce acid from lactose and use l-lactate as a sole carbon source. A polyphasic approach using phenotypic characterization, phylogenetic analysis of the 16S rRNA gene and of four housekeeping genes, as well as DNA–DNA hybridization studies and an analysis of the protein profiles by MALDI-TOF-MS, showed that these strains represented a novel species for which the name Aeromonas piscicola sp. nov. is proposed with isolate S1.2T (=CECT 7443T, =LMG 24783T) as the type strain.  相似文献   

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The taxonomic positions of soil isolates known as Streptomyces groups A, B and C were clarified. Comparative 16S rDNA sequence studies indicated that representatives of all three taxa formed distinct phyletic lines within the Streptomyces tree though the group A strains were shown to be related to Streptomyces griseus and associated validly described species. The taxonomic integrity of all three groups was highlighted by DNA:DNA relatedness and ribotype data though the group A strains encompassed a higher degree of genetic variation than the group B and C strains. In light of these and earlier phenotypic data it is proposed that Streptomyces groups A, B and C be given species status as Streptomyces sanglieri sp. nov., Streptomyces aureus sp. nov. and Streptomyces laceyi sp. nov., respectively. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

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Industrial glycerol obtained through the transesterification process using rapeseed oil did not support growth of several strains ofClostridium butyricum obtained from bacterial culture collections. Ten new strains ofC. butyricum were obtained from mud samples from a river, a stagnant pond, and a dry canal. These new isolates fermented the commercial glycerol and produced 1,3-propanediol as a major fermentation product with concomitant production of acetic and butyric acids. Four of the ten isolates were able to grow on industrial glycerol obtained from rapeseed oil. One strain,C. butyricum E5, was very resistant to high levels of glycerol and 1,3-propanediol. Using fed-batch fermentation, 109 g L–1 of industrial glycerol were converted into 58 g of 1,3-propanediol, 2.2 g of acetate and 6.1 g of butyrate per liter.  相似文献   

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Proton magnetic resonance spectra at 500 MHz are reported for the oxidized and reduced forms of the 2[4Fe-4S]-ferredoxin from Clostridium pasteurianum. The reduced protein showed additional peaks in the 10–60 ppm region, which were previously unobserved, and there were significant differences between oxidized and reduced states in the whole region. The electron exchange rate in partially reduced ferredoxin is slow on the n.m.r. time scale when reduced with sodium dithionite, but fast when zinc reduced methyl viologen is used as reducing agent. We explain the difference between fast and slow exchange as being due to the different chemical properties of the two reducing agents.  相似文献   

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Gram-negative, facultatively anaerobic bacterial strains were consistently isolated from oak trees displaying symptoms of extensive stem bleeding. In Britain, this disorder is called Acute Oak Decline (AOD). A similar condition has been noted on species of Mediterranean oak in Spain. The identity of bacterial isolates from symptomatic trees in both countries was investigated using molecular techniques and phenotypic assays. 16S rRNA gene sequencing indicated that the strains were most closely related to the genera Serratia, Kluyvera, Klebsiella and Raoultella (all>97%). Phylogenetic analysis revealed that the strains formed a distinct lineage within the family Enterobacteriaceae, which was confirmed by both gyrB- and rpoB-gene sequencing. DNA-DNA hybridization confirmed that the strains belonged to a single taxon which could also be differentiated phenotypically from its closest phylogenetic neighbours. The phylogenetic and phenotypic data both demonstrated that the strains isolated from oak represented a novel genus and species within the family Enterobacteriaceae for which the name Gibbsiella quercinecans gen. nov., sp. nov. (type strain=FRB 97(T)=LMG 25500(T)=NCPPB 4470(T)) is proposed.  相似文献   

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Bacteremia is an uncommon complication after polypectomy and colonoscopy. We report one of the first cases of Clostridium perfringens bacteremia after polypectomy. Our patient was a four years old boy with congenital polyposis, who underwent colonoscopy and polypectomy without complication. Approximately 12 h later he developed a fever and tachycardia with no other clinical symptoms. His blood cultures grew out penicillin susceptible C. perfringens and Enterococcus faecalis. He responded to antibiotic therapy and remained clinically asymptomatic for the duration of his course. There are a few reports of bacteremia after routine polypectomy, but no reported cases of C. perfringens bacteremia in the pediatric population. Clostridial sp. bacteremia can be fatal with devastating consequences if appropriate antibiotics and/or surgical debridement are delayed. Polymicrobial infection, as illustrated in our patient, is also common and can be a poor prognostic risk factor. Therefore, for patients with a history of polypectomy and new onset fever, anaerobic infections should be considered and empiric antibiotic therapy should include coverage for these organisms.  相似文献   

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As part of a study carried out for detecting Arcobacter spp. in shellfish, three mussel isolates that were Gram-negative slightly curved rods, non-spore forming, showed a new 16S rDNA-RFLP pattern with a specific identification method for the species of this genus. Sequences of the 16S rRNA gene and those of the housekeeping genes rpoB, gyrB and hsp60 provided evidence that these mussel strains belonged to an unknown genetic lineage within the genus Arcobacter. The similarity between the 16S rRNA gene sequence of the representative strain (F79-6T) and type strains of the other Arcobacter species ranged between 94.1% with A. halophilus and 99.1% with the recently proposed species A. defluvii (CECT 7697T). DDH results between strain F79-6T and the type strain of the latter species were below 70% (53 ± 3.0%). Phenotypic characteristics together with MALDITOF mass spectra differentiated the new mussel strains from all other Arcobacter species. All the results indicate that these strains represent a new species, for which the name Arcobacter ellisii sp. nov. with the type strain F79-6T (=CECT 7837T = LMG 26155T) is proposed.  相似文献   

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通过数值分类、SDS-全细胞蛋白电泳分析,对分离自西北黄土高原地区的木蓝根瘤菌进行了研究,获得了1个新类群。在此基础上,进行了中心菌株SHL042的16S rDNA全序列分析,得到系统发育树状图。 SHL042与 R.tropici A、 R.tropici B、 R.leguminosarum、 R etli、 Rhananesis、R. mongolense和R.gallicum构成一个发育分支,其与这些种模式菌株 16S rDNA全序列的相似性分别为95.4%、95.5%、96.3%、95.8%、96.3%、97.9%和97.7%,均大于95%,应属于同一个属。新类群群内DNA同源性大于80%,而中心菌株SHL042与分支内各已知种的DNA同源性小于50%,表明SHL042代表1个新的根瘤菌菌种。  相似文献   

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A novel actinomycete strain, designated YIM 30243T, was isolated from a soil sample in Yunnan Province, China. Based on the results of phenotypic and genotypic characteristics, strain YIM 30243T should be assigned to a new species of the genus Nocardia, for which the name Nocardia alba sp. nov. is proposed. The type strain is YIM 30243T (= CCTCC AA001030T = DSM 44684T).  相似文献   

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