scholarly journals Phylogeny of different Helicobacter pylori strains could not be explained by 16S rRNA gene due to high similarity in gene sequence across strains

2022 ◽  
Author(s):  
Wenfa Ng
Keyword(s):  
Helicobacter Pylori ◽  
16S Rrna ◽  
16S Rrna Gene ◽  
Phylogenetic Tree ◽  
Gene Sequence ◽  
Strain Level ◽  
16S Rrna Gene Sequence ◽  
Rrna Gene ◽  
Rrna Gene Sequence ◽  
Different Strains

Abstract Understanding the evolutionary relatedness of different strains of a species helped identify strain-specific differences that may be useful for disease diagnosis and treatment. Typically, such strain level typing would be augmented by molecular assays such as DNA sequencing, and phylogenetic tree analysis. This work utilizes public data on the 16S rRNA gene sequence of different strains of Helicobacter pylori to help plot the phylogenetic tree that describes the evolutionary trajectories of the different strains. Results from multiple sequence alignment reveals high level of conservation in 16S rRNA gene sequence across strains. This then translates into a phylogenetic tree structure that suggests very close evolutionary relationships of the different strains except for one outlier strain. Even in the case of the outlier strain, its evolutionary distance from other brethren was also not large. Overall, the results obtained in this study indicates that 16S rRNA gene may not capture strain-level phylogeny between different strains of the same species, and point to efforts in elucidating this phylogenetic effect in other genes of the species. Such genes may be involved in virulence during pathogenesis in humans, and may thus be subjected to higher evolutionary pressure and natural selection.

scholarly journals Lactobacillus hammesii sp. nov., isolated from French sourdough

2005 ◽  
Vol 55 (2) ◽  
pp. 763-767 ◽  
Author(s):  
Rosica Valcheva ◽  
Maher Korakli ◽  
Bernard Onno ◽  
Hervé Prévost ◽  
Iskra Ivanova ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Gene Sequence ◽  
Fragment Length Polymorphism ◽  
Sequence Similarity ◽  
16S Rrna Gene Sequence ◽  
Rrna Gene ◽  
Rrna Gene Sequence ◽  
Gene Sequence Analysis ◽  
Different Strains

Twenty morphologically different strains were chosen from French wheat sourdough isolates. Cells were Gram-positive, non-spore-forming, non-motile rods. The isolates were identified using amplified-fragment length polymorphism, randomly amplified polymorphic DNA and 16S rRNA gene sequence analysis. All isolates were members of the genus Lactobacillus. They were identified as representing Lactobacillus plantarum, Lactobacillus paralimentarius, Lactobacillus sanfranciscensis, Lactobacillus spicheri and Lactobacillus sakei. However, two isolates (LP38T and LP39) could be clearly discriminated from recognized Lactobacillus species on the basis of genotyping methods. 16S rRNA gene sequence similarity and DNA–DNA relatedness data indicate that the two strains belong to a novel Lactobacillus species, for which the name Lactobacillus hammesii is proposed. The type strain is LP38T (=DSM 16381T=CIP 108387T=TMW 1.1236T).

scholarly journals Streptomonospora litoralis sp. nov., a halophilic thiopeptides producer isolated from sand collected at Cuxhaven beach

2021 ◽  
Author(s):  
Shadi Khodamoradi ◽  
Richard L. Hahnke ◽  
Yvonne Mast ◽  
Peter Schumann ◽  
Peter Kämpfer ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Gene Sequence ◽  
Sequence Similarity ◽  
Bioinformatic Analysis ◽  
Biosynthetic Gene Cluster ◽  
16S Rrna Gene Sequence ◽  
Rrna Gene ◽  
Rrna Gene Sequence ◽  
Polar Lipid Profile

AbstractStrain M2T was isolated from the beach of Cuxhaven, Wadden Sea, Germany, in course of a program to attain new producers of bioactive natural products. Strain M2T produces litoralimycin and sulfomycin-type thiopeptides. Bioinformatic analysis revealed a potential biosynthetic gene cluster encoding for the M2T thiopeptides. The strain is Gram-stain-positive, rod shaped, non-motile, spore forming, showing a yellow colony color and forms extensively branched substrate mycelium and aerial hyphae. Inferred from the 16S rRNA gene phylogeny strain M2T affiliates with the genus Streptomonospora. It shows 96.6% 16S rRNA gene sequence similarity to the type species Streptomonospora salina DSM 44593 T and forms a distinct branch with Streptomonospora sediminis DSM 45723 T with 97.0% 16S rRNA gene sequence similarity. Genome-based phylogenetic analysis revealed that M2T is closely related to Streptomonospora alba YIM 90003 T with a digital DNA-DNA hybridisation (dDDH) value of 26.6%. The predominant menaquinones of M2T are MK-10(H6), MK-10(H8), and MK-11(H6) (> 10%). Major cellular fatty acids are iso-C16:0, anteiso C17:0 and C18:0 10-methyl. The polar lipid profile consisted of diphosphatidylglycerol phosphatidyl glycerol, phosphatidylinositol, phosphatidylcholine, phosphatidylethanolamine, three glycolipids, two unknown phospholipids, and two unknown lipids. The genome size of type strain M2T is 5,878,427 bp with 72.1 mol % G + C content. Based on the results obtained from phylogenetic and chemotaxonomic studies, strain M2T (= DSM 106425 T = NCCB 100650 T) is considered to represent a novel species within the genus Streptomonospora for which the name Streptomonospora litoralis sp. nov. is proposed.

scholarly journals Faecalicoccus acidiformans gen. nov., sp. nov., isolated from the chicken caecum, and reclassification of Streptococcus pleomorphus (Barnes et al. 1977), Eubacterium biforme (Eggerth 1935) and Eubacterium cylindroides (Cato et al. 1974) as Faecalicoccus pleomorphus comb. nov., Holdemanella biformis gen. nov., comb. nov. and Faecalitalea cylindroides gen. nov., comb. nov., respectively, within the family Erysipelotrichaceae

2014 ◽  
Vol 64 (Pt_11) ◽  
pp. 3877-3884 ◽  
Author(s):  
Celine De Maesschalck ◽  
Filip Van Immerseel ◽  
Venessa Eeckhaut ◽  
Siegrid De Baere ◽  
Margo Cnockaert ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Type Species ◽  
Gene Sequence ◽  
Sequence Similarity ◽  
16S Rrna Gene Sequence ◽  
Rrna Gene ◽  
Rrna Gene Sequence ◽  
Content Type ◽  
Link Type

Strains LMG 27428T and LMG 27427 were isolated from the caecal content of a chicken and produced butyric, lactic and formic acids as major metabolic end products. The genomic DNA G+C contents of strains LMG 27428T and LMG 27427 were 40.4 and 38.8 mol%. On the basis of 16S rRNA gene sequence similarity, both strains were most closely related to the generically misclassified Streptococcus pleomorphus ATCC 29734T. Strain LMG 27428T could be distinguished from S. pleomorphus ATCC 29734T based on production of more lactic acid and less formic acid in M2GSC medium, a higher DNA G+C content and the absence of activities of acid phosphatase and leucine, arginine, leucyl glycine, pyroglutamic acid, glycine and histidine arylamidases, while strain LMG 27428 was biochemically indistinguishable from S. pleomorphus ATCC 29734T. The novel genus Faecalicoccus gen. nov. within the family Erysipelotrichaceae is proposed to accommodate strains LMG 27428T and LMG 27427. Strain LMG 27428T ( = DSM 26963T) is the type strain of Faecalicoccus acidiformans sp. nov., and strain LMG 27427 ( = DSM 26962) is a strain of Faecalicoccus pleomorphus comb. nov. (type strain LMG 17756T = ATCC 29734T = DSM 20574T). Furthermore, the nearest phylogenetic neighbours of the genus Faecalicoccus are the generically misclassified Eubacterium cylindroides DSM 3983T (94.4 % 16S rRNA gene sequence similarity to strain LMG 27428T) and Eubacterium biforme DSM 3989T (92.7 % 16S rRNA gene sequence similarity to strain LMG 27428T). We present genotypic and phenotypic data that allow the differentiation of each of these taxa and propose to reclassify these generically misnamed species of the genus Eubacterium formally as Faecalitalea cylindroides gen. nov., comb. nov. and Holdemanella biformis gen. nov., comb. nov., respectively. The type strain of Faecalitalea cylindroides is DSM 3983T = ATCC 27803T = JCM 10261T and that of Holdemanella biformis is DSM 3989T = ATCC 27806T = CCUG 28091T.

scholarly journals 16S rRNA Gene Sequence Analysis ofPhotobacterium damselae and Nested PCR Method for Rapid Detection of the Causative Agent of Fish Pasteurellosis

1999 ◽  
Vol 65 (7) ◽  
pp. 2942-2946 ◽  
Author(s):  
Carlos R. Osorio ◽  
Matthew D. Collins ◽  
Alicia E. Toranzo ◽  
Juan L. Barja ◽  
Jesús L. Romalde
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Causative Agent ◽  
Nested Pcr ◽  
Gene Sequence ◽  
16S Rrna Gene Sequence ◽  
Rrna Genes ◽  
Rrna Gene ◽  
Rrna Gene Sequence ◽  
Photobacterium Damselae

ABSTRACT The causative agent of fish pasteurellosis, the organism formerly known as Pasteurella piscicida, has been reclassified asPhotobacterium damselae subsp. piscicida on the basis of 16S rRNA gene sequence comparisons and chromosomal DNA-DNA hybridization data; thus, this organism belongs to the same species asPhotobacterium damselae subsp. damselae(formerly Vibrio damselae). Since reassignment of P. damselae subsp. piscicida was based on only two strains, one objective of the present work was to confirm the taxonomic position of this fish pathogen by sequencing the 16S rRNA genes of 26 strains having different geographic and host origins. In addition, a nested PCR protocol for detection of P. damselae based on 16S rRNA was developed. This PCR protocol was validated by testing 35 target and 24 nontarget pure cultures, and the detection limits obtained ranged from 1 pg to 10 fg of DNA (200 to 20 cells). A similar level of sensitivity was observed when the PCR protocol was applied to fish tissues spiked with bacteria. The PCR approach described in this paper allows detection of the pathogen in mixed plate cultures obtained from asymptomatic fish suspected to be carriers of P. damselae subsp. piscicida, in which growth of this bacterium cannot be visualized. Our results indicate that the selective primers which we designed represent a powerful tool for sensitive and specific detection of fish pasteurellosis.

scholarly journals Paenibacillus xinjiangensis sp. nov., isolated from Xinjiang province in China

2006 ◽  
Vol 56 (11) ◽  
pp. 2579-2582 ◽  
Author(s):  
Jee-Min Lim ◽  
Che Ok Jeon ◽  
Dong-Jin Park ◽  
Li-Hua Xu ◽  
Cheng-Lin Jiang ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Gene Sequence ◽  
Sequence Similarity ◽  
Diaminopimelic Acid ◽  
16S Rrna Gene Sequence ◽  
Rrna Gene ◽  
Rrna Gene Sequence ◽  
16S Rrna Gene Sequences ◽  
Sequence Similarities

Strain B538T is a Gram-positive, motile, rod-shaped bacterium, which was isolated from Xinjiang province in China. This organism grew optimally at 30–35 °C and pH 8.0–8.5. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain B538T belonged to the genus Paenibacillus and chemotaxonomic data (DNA G+C content, 47.0 mol%; major isoprenoid quinone, MK-7; cell wall type, A1γ meso-diaminopimelic acid; major fatty acids, anteiso-C15 : 0 and C16 : 0) supported affiliation of the isolate with the genus Paenibacillus. Comparative 16S rRNA gene sequence analyses showed that the isolate was most closely related to Paenibacillus glycanilyticus DS-1T, with 16S rRNA gene sequence similarity of 98.1 %; sequence similarities to other members of the genus Paenibacillus used in the phylogenetic tree were less than 96.5 %. The DNA–DNA relatedness between strain B538T and P. glycanilyticus DS-1T was about 8.0 %. On the basis of physiological and molecular properties, strain B538T (=KCTC 3952T=DSM 16970T) is proposed as the type strain of a novel species within the genus Paenibacillus, for which the name Paenibacillus xinjiangensis sp. nov. is proposed.

scholarly journals Exiguobacterium aestuarii sp. nov. and Exiguobacterium marinum sp. nov., isolated from a tidal flat of the Yellow Sea in Korea

2005 ◽  
Vol 55 (2) ◽  
pp. 885-889 ◽  
Author(s):  
In-Gi Kim ◽  
Mi-Hwa Lee ◽  
Seo-Youn Jung ◽  
Jae Jun Song ◽  
Tae-Kwang Oh ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Tidal Flat ◽  
Yellow Sea ◽  
Type Strain ◽  
Gene Sequence ◽  
Sequence Similarity ◽  
16S Rrna Gene Sequence ◽  
Rrna Gene ◽  
Rrna Gene Sequence

Three Gram-variable, rod-shaped bacterial strains, TF-16T, TF-19 and TF-80T, were isolated from a tidal flat of Daepo Beach (Yellow Sea) near Mokpo City, Korea, and their taxonomic positions were investigated by a polyphasic approach. These isolates grew optimally in the presence of 2 % NaCl and at 30 °C. Their peptidoglycan types were based on l-Lys–Gly. The predominant menaquinone detected in the three strains was MK-7. The three strains contained large amounts of the branched fatty acids iso-C17 : 0, anteiso-C13 : 0, iso-C13 : 0 and iso-C15 : 0. The DNA G+C contents of strains TF-16T, TF-19 and TF-80T were 48·6, 48·4 and 48·0 mol%, respectively. The three strains formed a coherent cluster with Exiguobacterium species in a phylogenetic tree based on 16S rRNA gene sequences. They showed closest phylogenetic affiliation to Exiguobacterium aurantiacum, with 16S rRNA gene sequence similarity values of 98·1–98·3 %. The three strains exhibited 16S rRNA gene sequence similarity values of 94·0–94·6 % to the type strains of other Exiguobacterium species. Levels of DNA–DNA relatedness indicated that strains TF-16T and TF-19 and strain TF-80T are members of two species that are separate from E. aurantiacum. On the basis of phenotypic, phylogenetic and genetic data, strains TF-16T and TF-19 and strain TF-80T represent two novel species in the genus Exiguobacterium; the names Exiguobacterium aestuarii sp. nov. (type strain TF-16T=KCTC 19035T=DSM 16306T; reference strain TF-19) and Exiguobacterium marinum sp. nov. (type strain TF-80T=KCTC 19036T=DSM 16307T) are proposed.

scholarly journals Denitratisoma oestradiolicum gen. nov., sp. nov., a 17β-oestradiol-degrading, denitrifying betaproteobacterium

2006 ◽  
Vol 56 (7) ◽  
pp. 1547-1552 ◽  
Author(s):  
Michael Fahrbach ◽  
Jan Kuever ◽  
Ruth Meinke ◽  
Peter Kämpfer ◽  
Juliane Hollender
Keyword(s):  
Phylogenetic Analysis ◽  
16S Rrna ◽  
16S Rrna Gene ◽  
Gene Sequence ◽  
Municipal Wastewater ◽  
Treatment Plant ◽  
16S Rrna Gene Sequence ◽  
Physiological Data ◽  
Rrna Gene ◽  
Rrna Gene Sequence

A Gram-negative, motile, denitrifying bacterium (strain AcBE2-1T) was isolated from activated sludge of a municipal wastewater treatment plant using 17β-oestradiol (E2) as sole source of carbon and energy. Cells were curved rods, 0.4–0.8×0.8–2.0 μm in size, non-fermentative, non-spore-forming, oxidase-positive and catalase-negative. E2 was oxidized completely to carbon dioxide and water by reduction of nitrate to a mixture of dinitrogen monoxide and dinitrogen, with the intermediate accumulation of nitrite. Electron recoveries were between 90 and 100 %, taking assimilated E2 into account. With nitrate as the electron acceptor, the bacterium also grew on fatty acids (C2 to C6), isobutyrate, crotonate, dl-lactate, pyruvate, fumarate and succinate. Phylogenetic analysis of its 16S rRNA gene sequence revealed that strain AcBE2-1T represents a separate line of descent within the family Rhodocyclaceae (Betaproteobacteria). The closest relatives are the cholesterol-degrading, denitrifying bacteria Sterolibacterium denitrificans DSM 13999T and strain 72Chol (=DSM 12783), with <93.9 % sequence similarity. The G+C content of the DNA was 61.4 mol%. Detection of a quinone system with ubiquinone Q-8 as the predominant compound and a fatty acid profile that included high concentrations of C16 : 1 ω7c/iso-C15 : 0 2-OH and C16 : 0, in addition to C18 : 1 ω7c and small amounts of C8 : 0 3-OH, supported the results of the phylogenetic analysis. On the basis of 16S rRNA gene sequence data in combination with chemotaxonomic and physiological data, strain AcBE2-1T (=DSM 16959T=JCM 12830T) is placed in a new genus Denitratisoma gen. nov. as the type strain of the type species Denitratisoma oestradiolicum gen. nov., sp. nov.

Sign in / Sign up

Export Citation Format

Share Document