首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
A group of three motile facultative anaerobic marine bacteria were isolated from cultured Manila clams (Ruditapes philippinarum) in Galicia, north-western Spain. The strains were characterized phenotypically and genotypically. Phylogenetic analysis of the 16S rRNA gene and four housekeeping genes, RNA polymerase α-chain (rpoA), RecA protein (recA), the α-subunit of bacterial ATP synthase (atpA) and the uridine monophosphate (UMP) kinase (pyrH), indicated that these strains were closely related to the Vibrio splendidus clade. The amplified fragment length polymorphism (AFLP) fingerprints, DNA–DNA hybridizations and phylogenies of the housekeeping and 16S rRNA gene sequences showed that the three strains represented a different species from all currently described vibrios. The new species could be differentiated from its nearest neighbours on the basis of several phenotypic features. The three strains are therefore a novel species within the genus Vibrio, for which the name Vibrio gallaecicus is proposed, with the type strain being VB 8.9T(=CECT 7244T=LMG 24045T).  相似文献   

2.
The phenotypic and genotypic characteristics of seventeen Achromobacter strains representing MLST genogroups 2, 5, 7 and 14 were examined. Although genogroup 2 and 14 strains shared a DNA–DNA hybridization level of about 70%, the type strains of both genogroups differed in numerous biochemical characteristics and all genogroup 2 and 14 strains could by distinguished by nitrite reduction, denitrification and growth on acetamide. Given the MLST sequence divergence which identified genogroups 2 and 14 as clearly distinct populations, the availability of nrdA sequence analysis as a single locus identification tool for all Achromobacter species and genogroups, and the differential phenotypic characteristics, we propose to formally classify Achromobacter genogroups 2, 5, 7 and 14 as four novel Achromobacter species for which we propose the names Achromobacter insuavis sp. nov. (with strain LMG 26845T [= CCUG 62426T] as the type strain), Achromobacter aegrifaciens sp. nov. (with strain LMG 26852T [= CCUG 62438T] as the type strain), Achromobacter anxifer sp. nov. (with strain LMG 26857T [= CCUG 62444T] as the type strain), and Achromobacter dolens sp. nov. (with strain LMG 26840T [= CCUG 62421T] as the type strain).  相似文献   

3.
Five strains of gram negative bacteria, isolated from soybean (LPPA 221T, 222 and 223) and weeds (LPPA 816 and 1442), were analyzed by a polyphasic approach. The isolates showed variation in their phenotypic traits and were placed in the Pseudomonas fluorescens lineage, based on 16S rRNA gene sequence phylogeny, as a single but well separated cluster. MLSA analysis based on gyrB and rpoD sequences clustered the strains in a single branch in the Pseudomonas syringae group, and revealed P. viridiflava as closest relative. DNA–DNA hybridizations showed medium levels of DNA–DNA relatedness with the type strain of P. viridiflava (50%) and lower levels (<32%) with other type strains of the P. syringae group, supporting classification within a novel species of the genus Pseudomonas. The strains can be distinguished from species of the P. syringae group by the fatty acid C17:0 cyclo that is present in a low amount (2.5%) and from P. viridiflava by their inability to assimilate d-tartrate and d-sorbitol, and by the formation of red colonies on TTC medium. For this new species, the name Pseudomonas asturiensis sp. nov. is proposed. The type strain is LPPA 221T (=LMG 26898T = CECT 8095T).  相似文献   

4.
A group of four strains isolated from clams (Venerupis decussata and Venerupis philippinarum) in Galicia (NW Spain) were subjected to a polyphasic characterization, based on the phenotypic characteristics, the analysis of chemotaxonomic features, the sequencing of the 16S rRNA and five housekeeping (atpA, pyrH, recA, rpoA and rpoD) genes, as well as DNA–DNA hybridization (DDH). The analysis of the phenotypic and chemotaxonomic characteristics and the results of a phylogenetic study, based on the 16S rRNA gene sequence analysis and multilocus sequence analysis, clearly indicated that these strains belong to the genus Vibrio and were allocated between the Splendidus and Anguillarum clades showing a close relationship with the type strains of Vibrio tapetis (98.8 %), Vibrio pomeroyi (98.0 %) and Vibrio crassostreae (97.9 %). DNA–DNA hybridization results confirmed that these isolates constitute a new species. The name Vibrio cortegadensis sp. nov. is proposed with C 16.17T (=CECT 7227T=LMG 27474T) as the type strain.  相似文献   

5.
Gram-negative, facultatively anaerobic bacteria were isolated from symptomatic oak tissue in the UK and USA. Partial gyrB sequencing placed ten strains in the genus Brenneria, with B. goodwinii as the closest phylogenetic relative. The strains were investigated further using a polyphasic approach including MLSA (based on partial gyrB, rpoB, infB and atpD gene sequences), 16S rRNA gene sequencing, DNA–DNA relatedness studies and both phenotypic and chemotaxonomic assays. The MLSA and 16S rRNA gene analyses separated the strains into two groups based on origin, suggesting that they belong to Brenneria as two novel species. However, the DNA–DNA relatedness values revealed a closer relationship between the groups and indicated that they should belong to the same species. As the two groups of strains from the UK and USA can be differentiated from each other phenotypically and by ERIC PCR fingerprints, it is proposed to classify them as novel subspecies of a novel Brenneria species. The name Brenneria roseae sp. nov. (FRB 222T = LMG 27714T = NCPPB 4581T) is proposed, with Brenneria roseae subsp. roseae ssp. nov. (FRB 222T = LMG 27714T = NCPPB 4581T) for the strains from the UK and Brenneria roseae subsp. americana ssp. nov. (FRB 223T = LMG 27715T = NCPPB 4582T) for the strains from the USA.  相似文献   

6.
The phenotypic and genotypic characteristics of fourteen human clinical Achromobacter strains representing four genogroups which were delineated by sequence analysis of nusA, eno, rpoB, gltB, lepA, nuoL and nrdA loci, demonstrated that they represent four novel Achromobacter species. The present study also characterized and provided two additional reference strains for Achromobacter ruhlandii and Achromobacter marplatensis, species for which, thus far, only single strains are publicly available, and further validated the use of 2.1% concatenated nusA, eno, rpoB, gltB, lepA, nuoL and nrdA sequence divergence as a threshold value for species delineation in this genus. Finally, although most Achromobacter species can be distinguished by biochemical characteristics, the present study also highlighted considerable phenotypic intraspecies variability and demonstrated that the type strains may be phenotypically poor representatives of the species. We propose to classify the fourteen human clinical strains as Achromobacter mucicolens sp. nov. (with strain LMG 26685T [=CCUG 61961T] as the type strain), Achromobacter animicus sp. nov. (with strain LMG 26690T [=CCUG 61966T] as the type strain), Achromobacter spiritinus sp. nov. (with strain LMG 26692T [=CCUG 61968T] as the type strain), and Achromobacter pulmonis sp. nov. (with strain LMG 26696T [=CCUG 61972T] as the type strain).  相似文献   

7.
Four isolates of Gram-negative facultatively anaerobic bacteria, three of them producing NDM-1 carbapenemase, were isolated from hospitalized patients and outpatients attending two military hospitals in Rawalpindi, Pakistan, and studied for their taxonomic position. Initially the strains were phenotypically identified as Citrobacter species. Comparative analysis of 16S rRNA gene sequences then showed that the four strains shared >97%, but in no case >98.3%, 16S rRNA gene sequence similarities to members of the genera Citrobacter, Kluyvera, Pantoea, Enterobacter and Raoultella, but always formed a separate cluster in respective phylogenetic trees. Based on multilocus sequence analysis (MLSA) including partial recN, rpoA, thdF and rpoB gene sequence and respective amino acid sequence analysis it turned out that the strains also here always formed separate clusters. Based on further comparative analyses including DNA–DNA hybridizations, genomic fingerprint analysis using rep- and RAPD-PCRs and physiological tests, it is proposed to classify these four strains into the novel genus Pseudocitrobacter gen. nov. with a new species Pseudocitrobacter faecalis sp. nov. with strain 25 CITT (= CCM 8479T = LMG 27751T) and Pseudocitrobacter anthropi sp. nov. with strain C138T (= CCM 8478T = LMG 27750T), as the type strains, respectively.  相似文献   

8.
In this paper we analyze through a polyphasic approach several Bradyrhizobium strains isolated in Spain and Morocco from root nodules of Retama sphaerocarpa and Retama monosperma. All the strains have identical 16S rRNA genes and their closest relative species is Bradyrhizobium lablabi CCBAU 23086T, with 99.41% identity with respect to the strain Ro19T. Despite the closeness of the 16S rRNA genes, the housekeeping genes recA, atpD and glnII were divergent in Ro19T and B. lablabi CCBAU 23086T, with identity values of 95.71%, 93.75% and 93.11%, respectively. These differences were congruent with DNA–DNA hybridization analysis that revealed an average of 35% relatedness between the novel species and B. lablabi CCBAU 23086T. Also, differential phenotypic characteristics of the new species were found with respect to the already described species of Bradyrhizobium. Based on the genotypic and phenotypic data obtained in this study, we propose to classify the group of strains isolated from R. sphaerocarpa and R. monosperma as a novel species named Bradyrhizobium retamae sp. nov. (type strain Ro19T = LMG 27393T = CECT 8261T). The analysis of symbiotic genes revealed that some of these strains constitute a new symbiovar within genus Bradyrhizobium for which we propose the name “retamae”, that mainly contains nodulating strains isolated from Retama species in different continents.  相似文献   

9.
10.
11.
Comparison of HaeIII- and HpaII-restriction profiles of PCR-amplified 16S-23S rDNA ITS regions of Gluconacetobacter sp. LMG 1529T and SKU 1109 with restriction profiles of reference strains of acetic acid bacteria described by Tr?ek and Teuber [34] revealed the same but unique restriction profiles for LMG 1529T and SKU 1109. Further analyses of nearly complete 16S rRNA gene sequences, nearly complete 16S-23S rDNA ITS sequences, as well as concatenated partial sequences of the housekeeping genes dnaK, groEL and rpoB, allocated both strains to a single phylogenetic cluster well separated from the other species of the genus Gluconacetobacter. DNA–DNA hybridizations confirmed their novel species identity by 73% DNA–DNA relatedness between both strains, and values below the species level (<70%) between SKU 1109 and the type strains of the closest phylogenetic neighbors. The classification of strains LMG 1529T and SKU 1109 into a single novel species was confirmed also by AFLP and (GTG)5-PCR DNA fingerprinting data, as well as by phenotypic data. Strains LMG 1529T and SKU 1109 can be differentiated from their closely related Gluconacetobacter species, Gluconacetobacter entanii and Gluconacetobacter hansenii, by their ability to form 2-keto-d-gluconic acid from d-glucose, their ability to use d-mannitol, d-gluconate and glycerol as carbon source and form acid from d-fructose, and their ability to grow without acetic acid. The major fatty acid of LMG 1529T and SKU 1109 is C18:1ω7c (60.2–64.8%). The DNA G + C content of LMG 1529T and SKU 1109 is 62.5 and 63.3 mol% respectively. The name Gluconacetobacter maltaceti sp. nov. is proposed. The type strain is LMG 1529T (= NBRC 14815T = NCIMB 8752T).  相似文献   

12.
Three strains recovered from mussels (F26), sewage (SW28-13T) and pork meat (F41T) were characterized as Arcobacter. They did not appear to resemble any known species on the basis of their 16S rDNA-RFLP patterns and the rpoB gene analyses. However, strains F26 and SW28-13T appeared to be the same species. The 16S rRNA gene sequence similarity of strains SW28-13T and F41T to the type strains of all other Arcobacter species ranged from 94.1% to 99.6% and 93.4% to 98.8%, respectively. Phenotypic characteristics and the DNA–DNA hybridization (DDH) results showed that they belonged to 2 new Arcobacter species. A multilocus phylogenetic analysis (MLPA) with the concatenated sequences of 5 housekeeping genes (gyrA, atpA, rpoB, gyrB and hsp60) was used for the first time in the genus, showing concordance with the 16S rRNA gene phylogenetic analysis and DDH results. The MALDI-TOF mass spectra also discriminated these strains as two new species. The names proposed for them are Arcobacter cloacae with the type strain SW28-13T (=CECT 7834T = LMG 26153T) and Arcobacter suis with the type strain F41T (=CECT 7833T = LMG 26152T).  相似文献   

13.
Five isolates from marine fish (W3T, WM, W1S, S2 and S3) and three isolates misclassified as Photobacterium phosphoreum, originating from spoiled modified atmosphere packed stored cod (NCIMB 13482 and NCIMB 13483) and the intestine of skate (NCIMB 192), were subjected to a polyphasic taxonomic study. Phylogenetic analysis of 16S rRNA gene sequences showed that the isolates were members of the genus Photobacterium. Sequence analysis using the gapA, gyrB, pyrH, recA and rpoA loci showed that these isolates formed a distinct branch in the genus Photobacterium, and were most closely related to Photobacterium aquimaris, Photobacterium kishitanii, Photobacterium phosphoreum and Photobacterium iliopiscarium. The luxA gene was present in isolates W3T, WM, W1S, S2 and S3 but not in NCIMB 13482, NCIMB 13483 and NCIMB 192. AFLP and (GTG)5-PCR fingerprinting indicated that the eight isolates represented at least five distinct genotypes. DNA–DNA hybridizations revealed 89% relatedness between isolate W3T and NCIMB 192, and values below 70% with the type strains of the phylogenetically closest species, P. iliopiscarium LMG 19543T, P. kishitanii LMG 23890T, P. aquimaris LMG 26951T and P. phosphoreum LMG4233T. The strains of this new taxon could also be distinguished from the latter species by phenotypic characteristics. Therefore, we propose to classify this new taxon as Photobacterium piscicola sp. nov., with W3T (=NCCB 100098T = LMG 27681T) as the type strain.  相似文献   

14.
15.
Two Gram-negative strains obtained from tank water in a scallop hatchery in Norway, were phenotypically and genotypically characterized in order to clarify their taxonomic position. On the basis of 16S rRNA gene sequence analysis, these isolates, ATF 5.2T and ATF 5.4T, were included in the genus Halomonas, being their closest relatives H. smyrnensis and H. taeanensis, with similarities of 98.9% and 97.7%, respectively. Sequence analysis of the housekeeping genes atpA, ftsZ, gyrA, gyrB, mreB, rpoB, rpoD, rpoE, rpoH, rpoN and rpoS clearly differentiated the isolates from the currently described Halomonas species, and the phylogenetic analysis using concatenated sequences of these genes located them in two robust and independent branches. DNA–DNA hybridization (eDDH) percentage, together with average nucleotide identity (ANI), were calculated using the complete genome sequences of the strains, and demonstrate that the isolates constitute two new species of Halomonas, for which the names of Halomonas borealis sp. nov. and Halomonas niordiana sp. nov. are proposed, with type strains ATF 5.2T (=CECT 9780T = LMG 31367T) and ATF 5.4T (=CECT 9779T = LMG 31227T), respectively.  相似文献   

16.
Four red-pigmented isolates, with optimum growth temperatures of approximately 55–60 °C and an optimum pH for growth between 7.5 and 8.5, were recovered from hot springs in Central France. Phylogenetic analysis of the 16S rRNA gene sequences showed that these organisms represented a new species of the genus Meiothermus. The new isolates could be distinguished from other strains of the species of the genus Meiothermus primarily by the glycolipid profile and fatty acid composition because these organisms lacked the hydroxy fatty acids and the glycolipid variant GL-1a found in all other isolates of the species of Meiothermus examined. On the basis of the results presented here we propose the name Meiothermus rufus for the new species, which is represented by strains CAL-4T (=DSM 22234T=LMG 24878T) and CAL-12 (=DSM 22235=LMG 24879). We also propose emending the genus Meiothermus to include strains that have only one glycolipid instead of two glycolipid variants.  相似文献   

17.
The Aeromonas group 501, also named Aeromonas sp. HG13, is taxonomically close to A. schubertii. Results obtained in previous studies, including DNA–DNA hybridization and DNA fingerprinting, suggest that Aeromonas group 501 could constitute a different Aeromonas species. In this work we have performed a polyphasic study with the two strains comprising the Aeromonas sp. HG13 in order to propose a formal species name. They could be differentiated from A. schubertii by the indole and lysine decarboxylase tests and the utilization of l-lactate. Phenotypically, both strains were also easily separated from the other Aeromonas species. Sequence analysis of the 16S rRNA gene showed high sequence similarities (>97%) between Aeromonas group 501 and all Aeromonas species. Nevertheless, sequence divergences of cpn60, dnaJ, gyrB and rpoD genes were higher than the intraspecific threshold values established for each gene (3.5%, 3.3%, 2.3% and 2.6%, respectively), while sequence divergences between strains CDC 2478-85T and CDC 2555-87 were low (0.6–1.1%). The DNA G+C content of the type strain was 62.2 mol%. Phenotypic and genotypic evidence strongly suggests that the Aeromonas group 501 is a novel species of the genus Aeromonas, for which the name Aeromonas diversa sp. nov. is proposed. The type strain is CDC 2478-85T (=CECT 4254T=ATCC 43946T=LMG 17321T).  相似文献   

18.
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   

19.
In 2010, cream-coloured, Gram-negative staining, facultatively anaerobic enterobacteria were isolated from a single black oak tree (Quercus kelloggii) exhibiting decline symptoms in southern California, USA. These 12 isolates were tentatively identified as Gibbsiella quercinecans based on partial gyrB sequencing. Closer examination of the strains using multilocus sequence analysis, based on partial sequences of gyrB, rpoB, infB and atpD genes, and almost complete 16S rRNA gene sequencing suggested that the isolates belong to a novel taxon within the genus Gibbsiella with G. quercinecans as their closest phylogenetic relative. DNA–DNA relatedness studies confirmed that the strains belong to a single taxon in Gibbsiella, which can be differentiated from other members of the genus by several phenotypic traits. Therefore, the name Gibbsiella greigii sp. nov. is proposed for this novel species isolated from symptomatic Q. kelloggii in the USA with FRB 224T (=LMG 27716T = NCPPB 4583T) as the type strain.  相似文献   

20.
In a survey of rhizobia associated with the native legumes in Yunnan Province, China, seven and nine strains isolated from the root nodules of Psoralea corylifolia, Sesbania cannabina and Medicago lupulina were respectively classified into the novel genomic species groups I and II in the genus Ensifer (former Sinorhizobium) based on the sequence analyses of the 16S rRNA gene. Analyses of concatenated housekeeping genes (atpD, recA and glnII) further revealed that they were distinct lineages in the genus, and group I was most similar to Ensifer terangae and Ensifer garamanticus (both with 94.2% similarity), while group II was most similar to Ensifer adhaerens (94.0%). These groups could be distinguished from closely related species by DNA–DNA relatedness, MALID-TOF MS, cellular fatty acid profiles and a series of phenotypic characters. Therefore, two novel species were proposed: Ensifer psoraleae sp. nov. (seven strains, type strain CCBAU 65732T = LMG 26835T = HAMBI 3286T) and Ensifer sesbaniae sp. nov. (nine strains, type strain CCBAU 65729T = LMG 26833T = HAMBI 3287T). They had a DNA G + C mol% (Tm) of 58.9 and 60.4, respectively. Both of the type strains formed effective nodules on common bean (Phaseolus vulgaris) and their hosts of origin. In addition, the previously described species Sinorhizobium morelense and Sinorhizobium americanum were renamed as Ensifer morelense comb. nov. and Ensifer americanum comb. nov. according to the accumulated data from different studies.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号