scholarly journals Divergence between the Highly Virulent Zoonotic Pathogen Helicobacter heilmannii and Its Closest Relative, the Low-Virulence “Helicobacter ailurogastricus” sp. nov.

2015 ◽  
Vol 84 (1) ◽  
pp. 293-306 ◽  
Author(s):  
Myrthe Joosten ◽  
Sara Lindén ◽  
Mirko Rossi ◽  
Alfred Chin Yen Tay ◽  
Emma Skoog ◽  
...  

Helicobacter heilmanniinaturally colonizes the stomachs of dogs and cats and has been associated with gastric disorders in humans. Nine felineHelicobacterstrains, classified asH. heilmanniibased onureABand 16S rRNA gene sequences, were divided into a highly virulent and a low-virulence group. The genomes of these strains were sequenced to investigate their phylogenetic relationships, to define their gene content and diversity, and to determine if the differences in pathogenicity were associated with the presence or absence of potential virulence genes. The capacities of these helicobacters to bind to the gastric mucosa were investigated as well. Our analyses revealed that the low-virulence strains do not belong to the speciesH. heilmanniibut to a novel, closely related species for which we propose the nameHelicobacter ailurogastricus. Several homologs ofH. pylorivirulence factors, such as IceA1, HrgA, and jhp0562-like glycosyltransferase, are present inH. heilmanniibut absent inH. ailurogastricus. Both species contain a VacA-like autotransporter, for which the passenger domain is remarkably larger inH. ailurogastricusthan inH. heilmannii. In addition,H. ailurogastricusshows clear differences in binding to the gastric mucosa compared toH. heilmannii. These findings highlight the low-virulence character of this novelHelicobacterspecies.

2013 ◽  
Vol 63 (Pt_2) ◽  
pp. 723-728 ◽  
Author(s):  
Neha Niharika ◽  
Hana Moskalikova ◽  
Jasvinder Kaur ◽  
Fazlurrahman Khan ◽  
Miroslava Sedlackova ◽  
...  

A yellow-pigmented bacterial strain, designated LL01T, was isolated from hexachlorocyclohexane (HCH)-contaminated soil at Spolana Neratovice, a former Czech producer of lindane. A neighbour-joining tree based on 16S rRNA gene sequences showed that strain LL01T occupied a distinct phylogenetic position in the Sphingobium cluster, showing highest similarity to Sphingobium rhizovicinum CC-FH12-1T (98.5 %). The DNA G+C content of strain LL01T was 66.1 mol%. The predominant respiratory pigment was ubiquinone Q-10. The polar lipid profile of strain LL01T also corresponded to those reported for other Sphingobium species (phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylcholine, phosphatidylglycerol, phosphatidylmonomethylethanolamine, phosphatidyldimethylethanolamine, sphingoglycolipids), supporting its identification as a member of the genus Sphingobium . Spermidine was the major polyamine observed. The results obtained from DNA–DNA hybridization and biochemical and physiological tests clearly distinguished strain LL01T from closely related species of the genus Sphingobium . Therefore, strain LL01T represents a novel species of the genus Sphingobium , for which the name Sphingobium czechense sp. nov. is proposed (type strain LL01T = CCM 7979T = DSM 25410T).


2012 ◽  
Vol 62 (Pt_12) ◽  
pp. 3030-3035 ◽  
Author(s):  
Eu Jin Chung ◽  
Tae Soon Park ◽  
Che Ok Jeon ◽  
Young Ryun Chung

A novel bacterial strain, YC7001T, was isolated from the rhizosphere soil of rice collected at Jinju, Korea, and was characterized using a polyphasic approach. Cells of strain YC7001T were Gram-negative-staining, yellow-pigmented, rod-shaped, aerobic, heterotrophic and non-motile. Strain YC7001T grew optimally at 25–30 °C, pH 5.0–8.0 and degraded gelatin, cellulose and chitin. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain YC7001T belonged to the genus Chitinophaga in the family Chitinophagaceae . The most closely related species were Chitinophaga sancti NBRC 15057T (96.9 %), Chitinophaga ginsengisoli Gsoil 052T (95.9 %), Chitinophaga pinensis DSM 2588T (95.7 %), Chitinophaga filiformis IFO 15056T (95.7 %) and Chitinophaga niabensis JS13-10T (95.0 %). The DNA–DNA relatedness value of strain YC7001T with C. sancti NBRC 15057T was 15.2±0.6 %. Strain YC7001T contained MK-7 as the major menaquinone and homospermidine as the major polyamine. The major fatty acids of strain YC7001T were C15 : 0 iso, C16 : 1ω5c and C17 : 0 iso 3-OH. The polar lipids were phosphatidylethanolamine, unknown aminolipids and unknown lipids. The total genomic DNA G+C content was 41.3 mol%. On the basis of phenotypic, chemotaxonomic and phylogenetic analyses, strain YC7001T represents a novel species of the genus Chitinophaga , in the family Chitinophagaceae , for which the name Chitinophaga oryziterrae sp. nov. is proposed. The type strain is YC7001T ( = KACC 14533T = JCM 16595T).


2011 ◽  
Vol 53 (4) ◽  
pp. 207-212 ◽  
Author(s):  
Rito Polanco ◽  
Víctor Salazar ◽  
Nelson Reyes ◽  
María Alexandra García-Amado ◽  
Fabián Michelangeli

Non-H. pylori helicobacters (NHPH) have been demonstrated as gastric spiral-shaped bacteria in specimens obtained from dogs; however, their roles in the pathogenesis of upper gastrointestinal disease have not yet been clearly established. The purpose of this study was to evaluate the prevalence of NHPH DNA in the gastric mucosa of dogs and its association with histopathology. Helicobacter was detected through histopathological techniques, PCR, and FISH analysis from fundic biopsies of twenty dogs with or without signs of gastrointestinal disease. PCR and FISH were based on partial 16S rRNA gene sequences. Nineteen dogs showed mild to marked gastritis in the fundus, and only one dog had a healthy gastric mucosa. NHPH DNA was detected in 18 dogs with gastritis and one with normal gastric mucosa. However, there was no significant correlation between the presence of NHPH DNA and the degree of gastritis. These results show a high prevalence of NHPH DNA in the gastric mucosa of dogs from Venezuela. Further studies are necessary to determine a possible association between a specific NHPH species and the degree of gastritis.


2014 ◽  
Vol 64 (Pt_6) ◽  
pp. 2072-2078 ◽  
Author(s):  
David Durán ◽  
Luis Rey ◽  
Juan Mayo ◽  
Doris Zúñiga-Dávila ◽  
Juan Imperial ◽  
...  

A group of strains isolated from root nodules of Phaseolus lunatus (Lima bean) in Peru were characterized by genotypic, genomic and phenotypic methods. All strains possessed identical 16S rRNA gene sequences that were 99.9 % identical to that of Bradyrhizobium lablabi CCBAU 23086T. Despite having identical 16S rRNA gene sequences, the Phaseolus lunatus strains could be divided into two clades by sequence analysis of recA, atpD, glnII, dnaK and gyrB genes. The genome sequence of a representative of each clade was obtained and compared to the genomes of closely related species of the genus Bradyrhizobium . Average nucleotide identity values below the species circumscription threshold were obtained when comparing the two clades to each other (88.6 %) and with all type strains of the genus Bradyrhizobium (≤92.9 %). Phenotypes distinguishing both clades from all described and closely related species of the genus Bradyrhizobium were found. On the basis of the results obtained, two novel species, Bradyrhizobium paxllaeri sp. nov. (type strain LMTR 21T = DSM 18454T = HAMBI 2911T) and Bradyrhizobium icense sp. nov. (type strain LMTR 13T = HAMBI 3584T = CECT 8509T = CNPSo 2583T), are proposed to accommodate the uncovered clades of Phaseolus lunatus bradyrhizobia. These species share highly related but distinct nifH and nodC symbiosis genes.


2014 ◽  
Vol 64 (Pt_2) ◽  
pp. 528-532 ◽  
Author(s):  
Hyo-Jin Lee ◽  
Kyung-Sook Whang

A Gram-stain-positive, novel actinobacterium, designated strain JL-6T, was isolated from the litter of a bamboo (Sasa borealis) forest in Damyang, Korea. Strain JL-6T had white‐grey, smooth, cylindrical spores that were borne in straight, long spore-chains. The novel strain grew aerobically at 15–28 °C (optimum, 28 °C), pH 4.0–8.0 (optimum, pH 5.5) and with 0–1.5 % (w/v) NaCl. The cell-wall peptidoglycan contained ll-diaminopimelic acid, glutamic acid, alanine and glycine. The predominant menaquinones were MK-9(H6) and MK-9(H8). Whole-cell hydrolysates mainly contained glucose and ribose. Phosphatidylinositol and phosphatidylcholine were the diagnostic phospholipids. The G+C content of the genomic DNA was 72.8 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain JL-6T belonged to the genus Streptomyces with sequence similarities ranging from 97.3 % to 98.3 %. However, DNA–DNA hybridization between JL-6T and the closest related strain, Streptomyces turgidiscabies , ATCC 700248T and other closely related species in the genus Streptomyces showed <50 % relatedness. Based on these observations, strain JL-6T is proposed to represent a novel species of the genus Streptomyces , for which the name Streptomyces graminilatus sp. nov. is proposed. The type strain is JL-6T ( = KACC 16470T = NBRC 108882T).


2013 ◽  
Vol 63 (Pt_4) ◽  
pp. 1267-1272 ◽  
Author(s):  
Haji Khan ◽  
Eu Jin Chung ◽  
Dong Young Kang ◽  
Che Ok Jeon ◽  
Young Ryun Chung

A Gram-negative, rod-shaped, pale-orange-pigmented bacterial strain with xylan-degrading activity designated YC7004T was isolated from a rotten-wood sample collected at Jinju, Korea, and its taxonomic position was investigated by using a polyphasic approach. The strain grew optimally on R2A medium at 30 °C and at pH 6. The major isoprenoid quinone was MK7 and major fatty acids were summed feature 3, iso-C15 : 0, C16 : 0, iso-C17 : 0 3-OH, iso-C17 : 1ω9c and C16 : 1ω5c. The G+C content of the genomic DNA was 40.0 mol%. Phylogenetic analysis based on the 16S rRNA gene sequences showed that the strain belongs to the genus Mucilaginibacter in the family Sphingobacteriaceae . The most closely related species were Mucilaginibacter daejeonensis (95.5 %), Mucilaginibacter frigoritolerans (94.6 %) and Mucilaginibacter mallensis (94.0 %). Based on the phylogenetic and chemotaxonomic data analyses, strain YC7004T represents a novel species of the genus Mucilaginibacter with the proposed name of Mucilaginibacter jinjuensis sp. nov. The type strain is YC7004T ( = KACC 16571T = NBRC 108856T).


2013 ◽  
Vol 63 (Pt_5) ◽  
pp. 1885-1890 ◽  
Author(s):  
Sanghwa Park ◽  
Susumu Yoshizawa ◽  
Yuki Muramatsu ◽  
Yasuyoshi Nakagawa ◽  
Akira Yokota ◽  
...  

A coccoid and amorphous-shaped, non-gliding, proteorhodopsin-containing, yellow bacterium, designated strain SG-18T, was isolated from seawater in the western North Pacific Ocean near Japan. The strain was Gram-stain-negative, obligately aerobic, heterotrophic and oxidase-positive. It hydrolysed aesculin but not DNA, urea, gelatin or agar. Growth occurred in the presence of 1–5 % NaCl, with optimum growth at 2 % NaCl. The strain grew at 15–37 °C with an optimum temperature of 25–30 °C. The DNA G+C content of the genomic DNA of strain SG-18T was 47.0 mol% (HPLC). The predominant isoprenoid quinone was MK-6, and major cellular fatty acids were iso-C15 : 1 G, iso-C15 : 0, iso-C15 : 0 3-OH. Phylogenetic trees generated by using 16S rRNA gene sequences revealed that strain SG-18T belonged to the family Flavobacteriaceae and showed 92.7 % sequence similarity to the most closely related species, Croceitalea eckloniae DOKDO 025T. On the basis of phenotypic and phylogenetic features, strain SG-18T is classified as representing a novel species of a new genus within the family Flavobacteriaceae , for which the name Aureicoccus marinus gen. nov., sp. nov. is proposed. The type strain of the type species is SG-18T ( = NBRC 108814T = KCTC 23967T).


Author(s):  
István Szabó ◽  
Jafar Al-Omari ◽  
Gábor Soma Szerdahelyi ◽  
Júlia Radó ◽  
Edit Kaszab ◽  
...  

A Gram-stain-negative, aerobic, non-spore-forming, rod-shaped bacterial strain (UP-52T) was isolated from hydrocarbon-polluted groundwater located near an oil refinery in Tiszaujvaros, Hungary. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the isolate belongs to the genus Dyadobacter in the family Cytophagaceae . Its closely related species are Dyadobacter frigoris (98.00 %), Dyadobacter koreensis (97.64 %), Dyadobacter psychrophilus (97.57 %), Dyadobacter ginsengisoli (97.56 %) and Dyadobacter psychrotolerans (97.20 %). The predominant fatty acids are summed feature 3 (C16 : 1  ω7c and/or C16 : 1  ω7c/C16 : 1  ω6c), C15 : 0 iso, C16 : 1  ω5c and C17 : 0 iso 3OH. The predominant respiratory quinone detected in strain UP-52T is quinone MK-7. The dominant polar lipids are glycolipid, phosphoaminolipid, phospholipid and aminolipid. The DNA G+C content is 40.0 mol%. Flexirubin-type pigment was present. Based on these phenotypic, chemotaxonomic and phylogenetic results, UP-52T represents a novel species of the genus Dyadobacter , for which the name Dyadobacter subterraneus sp. nov. is proposed. The type strain is UP-52T (=NCAIM B.02653T=CCM 9030T).


2013 ◽  
Vol 63 (Pt_3) ◽  
pp. 934-938 ◽  
Author(s):  
Wen-Ming Chen ◽  
Rey-Chang Chang ◽  
Chih-Yu Cheng ◽  
Yu-Wen Shiau ◽  
Shih-Yi Sheu

A novel bacterium, designated strain JchiT, was isolated from soil in Taiwan and characterized using a polyphasic approach. Cells of strain JchiT were aerobic, Gram-stain-negative, motile and rod-shaped. They contained poly-β-hydroxybutyrate granules and formed dark-yellow colonies. Growth occurred at 20–37 °C (optimum between 25 and 30 °C), at pH 6.0–8.0 (optimum between pH 7.0 and pH 8.0) and with 0–2 % NaCl (optimum between 0 and 1 %). Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain JchiT belonged to the genus Jeongeupia and that its closest neighbour was Jeongeupia naejangsanensis BIO-TAS4-2T (98.0 % sequence similarity). The major fatty acids (>10 %) of strain JchiT were summed feature 3 (comprising C16 : 1ω7c and/or C16 : 1ω6c), C16 : 0 and C18 : 1ω7c. The major cellular hydroxy fatty acid was C12 : 0 3-OH. The isoprenoid quinone was Q-8 and the genomic DNA G+C content was 66.1 mol%. The polar lipid profile consisted of a mixture of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylserine and two unidentified phospholipids. The DNA–DNA relatedness value between strain JchiT and J. naejangsanensis BIO-TAS4-2T was about 41.0 %. On the basis of the genotypic and phenotypic data, strain JchiT represents a novel species in the genus Jeongeupia , for which the name Jeongeupia chitinilytica sp. nov. is proposed. The type strain is JchiT ( = BCRC 80367T  = KCTC 23701T).


Author(s):  
Jun-Jie Ying ◽  
Zhi-Cheng Wu ◽  
Yuan-Chun Fang ◽  
Lin Xu ◽  
Cong Sun

Parvularcula flava was proposed as a novel member of genus Parvularcula in 2016. Some time earlier, Aquisalinus flavus has been proposed as a novel species of a novel genus named Aquisalinus . When comparing the 16S rRNA gene sequences of type strains P. flava NH6-79T and A. flavus D11M-2T, they showed 97.9 % sequence identity, much higher than the sequence identities 92.7–94.3 % between P. flava NH6-79T and type strains in the genus Parvularcula , indicating that the later proposed novel taxon Parvularcula flava need reclassification. The phylogenetic trees based on 16S rRNA gene sequences and genome sequences both showed that P. flava NH6-79T and A. flavus D11M-2T formed a separated branch away from strains in the genera Parvularcula , Marinicaulis and Amphiplicatus . The average amino acid identity and average nucleotide identity values of P. flava NH6-79T and A. flavus D11M-2T were 87.9 and 85.0 %, respectively, much higher than the values between P. flava NH6-79T and other closely related type strains (54.3 %–58.1 % and 68.6–70.4 %, respectively). P. flava NH6-79T and A. flavus D11M-2T also contained summed feature 8 (C18 : 1  ω6c and/or C18 : 1  ω7c) and C16 : 0 as major fatty acids, distinguishing them from other closely related taxa. Based on the results of the phylogenetic, comparative genomic and phenotypic analyses, Parvularcula flava should be reclassified as Aquisalinus luteolus nom. nov. and the description of genus Aquisalinus is emended.


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