scholarly journals Rhizobium oryzicola sp. nov., potential plant-growth-promoting endophytic bacteria isolated from rice roots

2015 ◽  
Vol 65 (Pt_9) ◽  
pp. 2931-2936 ◽  
Author(s):  
Xiao-Xia Zhang ◽  
Ju-Sheng Gao ◽  
Yan-Hua Cao ◽  
Rizwan Ali Sheirdil ◽  
Xiu-Cheng Wang ◽  
...  

Bacterial strains ZYY136T and ZYY9 were isolated from surface-sterilized rice roots from a long-term experiment of rice–rice–Astragalus sinicus rotation. The 16S rRNA gene sequences of strains ZYY136T and ZYY9 showed the highest similarity, of 97.0  %, to Rhizobium tarimense PL-41T. Sequence analysis of the housekeeping genes recA, thrC and atpD clearly differentiated the isolates from currently described species of the genus Rhizobium. The DNA–DNA relatedness value between ZYY136T and ZYY9 was 82.3  %, and ZYY136T showed 34.0  % DNA–DNA relatedness with the most closely related type strain, R. tarimense PL-41T. The DNA G+C content of strain ZYY136T was 58.1 mol%. The major cellular fatty acids were summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), C16 : 0 and C16 : 0 3-OH. Strains ZYY136T and ZYY9 could be differentiated from the previously defined species of the genus Rhizobium by several phenotypic characteristics. Therefore, we conclude that strains ZYY136T and ZYY9 represent a novel species of the genus Rhizobium, for which the name Rhizobium oryzicola sp. nov. is proposed (type strain ZYY136T = ACCC 05753T = KCTC 32088T).

2011 ◽  
Vol 61 (8) ◽  
pp. 1802-1810 ◽  
Author(s):  
Anna E. Dinsdale ◽  
Gillian Halket ◽  
An Coorevits ◽  
Anita Van Landschoot ◽  
Hans-Jürgen Busse ◽  
...  

Nineteen thermophilic, aerobic, endospore-forming bacterial strains were subjected to 16S rRNA gene sequence analysis. Eight of these strains had been received as cultures of Geobacillus kaustophilus, G. lituanicus, G. stearothermophilus, ‘G. thermoleovorans subsp. stromboliensis’, G. vulcani, ‘Bacillus caldolyticus’, ‘B. caldotenax’ and ‘B. caldovelox’, but they showed close relationships with the type strain of G. thermoleovorans, as did two other strains received as G. thermoleovorans. All strains underwent further taxonomic analysis by API and other phenotypic tests and fatty acid methyl ester analysis, and selected strains were analysed for their polar lipids and for DNA relatedness. The 11 strains that formed the G. thermoleovorans 16S rRNA cluster also showed some phenotypic similarities, and DNA relatedness data support the reassignment of the strains received as G. kaustophilus, G. lituanicus, ‘G. thermoleovorans subsp. stromboliensis’, G. vulcani, ‘B. caldolyticus’, ‘B. caldotenax’ and ‘B. caldovelox’, and one of the G. stearothermophilus strains, as members of the species G. thermoleovorans. Four other strains received as G. kaustophilus were misnamed; two were identified as G. stearothermophilus and two appeared to be closely related to Anoxybacillus rupiensis. One strain received as G. stearothermophilus remained unidentified. On the basis of a single strain, Geobacillus thermocatenulatus was shown to represent a distinct species, but study of the type strain of Geobacillus gargensis showed this species to be a later heterotypic synonym of Geobacillus thermocatenulatus. Emended descriptions of Geobacillus thermoleovorans and Geobacillus thermocatenulatus are therefore presented.


2010 ◽  
Vol 60 (8) ◽  
pp. 1897-1903 ◽  
Author(s):  
Jia-Yue Zhang ◽  
Xing-Yu Liu ◽  
Shuang-Jiang Liu

Two bacterial strains, DNG5T and V3M1T, isolated from forest soil of the Changbai mountains in China, were characterized using a polyphasic approach. Analysis of their 16S rRNA gene sequences indicated that strains DNG5T and V3M1T were phylogenetically related to members of the genus Agrococcus (96.0–98.4 % similarity) and Micrococcus (96.7–98.0 % similarity), respectively, within the order Actinomycetales. Strains DNG5T and V3M1T were Gram-stain-positive and strictly aerobic and formed yellow colonies on LB agar. Cells of strain DNG5T were short, non-motile rods, 0.4–0.5×0.8–1.0 μm. Strain DNG5T contained MK-10 and MK-11 as the major respiratory quinones and anteiso-C15 : 0 (49.2 %) and iso-C16 : 0 (22.4 %) as the major fatty acids. The diamino acid in the peptidoglycan of strain DNG5T was 2,4-diaminobutyric acid and the murein was of the acetyl type. Cells of strain V3M1T were cocci, 0.6–0.7 μm in diameter. The cell-wall peptidoglycan of strain V3M1T contained the amino acids lysine, glutamic acid, alanine and glycine. Strain V3M1T contained MK-7, MK-7(H2), MK-8 and MK-8(H2) as respiratory quinones and anteiso-C15 : 0 (78.2 %) and iso-C15 : 0 (13.1 %) as the major cellular fatty acids. The DNA G+C contents of strains DNG5T and V3M1T were 75.9 and 67.2 mol%, respectively. The DNA–DNA relatedness of strain DNG5T to Agrococcus jejuensis DSM 22002T, A. jenensis JCM 9950T, A. baldri JCM 12132T and A. citreus JCM 12398T was 58.3, 43.9, 36.1 and 54.1 %, respectively. The DNA–DNA relatedness of strain V3M1T to Micrococcus luteus CGMCC 1.2299T, M. antarcticus CGMCC 1.2373T and M. lylae CGMCC 1.2300T was 57.5, 45.4 and 39.0 %, respectively. Combining phenotypic and genotypic traits, strain DNG5T represents a novel species of the genus Agrococcus, for which the name Agrococcus terreus sp. nov. is proposed, with DNG5T (=CGMCC 1.6960T =NBRC 104260T) as the type strain. Strain V3M1T represents a novel species of the genus Micrococcus, for which the name Micrococcus terreus sp. nov. is proposed, with V3M1T (=CGMCC 1.7054T =NBRC 104258T) as the type strain.


2015 ◽  
Vol 65 (Pt_12) ◽  
pp. 4424-4433 ◽  
Author(s):  
Jakeline Renata Marçon Delamuta ◽  
Renan Augusto Ribeiro ◽  
Ernesto Ormeño-Orrillo ◽  
Marcia Maria Parma ◽  
Itamar Soares Melo ◽  
...  

Biological nitrogen fixation is a key process for agricultural production and environmental sustainability, but there are comparatively few studies of symbionts of tropical pasture legumes, as well as few described species of the genus Bradyrhizobium, although it is the predominant rhizobial genus in the tropics. A detailed polyphasic study was conducted with two strains of the genus Bradyrhizobium used in commercial inoculants for tropical pastures in Brazil, CNPSo 1112T, isolated from perennial soybean (Neonotonia wightii), and CNPSo 2833T, from desmodium (Desmodium heterocarpon). Based on 16S-rRNA gene phylogeny, both strains were grouped in the Bradyrhizobium elkanii superclade, but were not clearly clustered with any known species. Multilocus sequence analysis of three (glnII, gyrB and recA) and five (plus atpD and dnaK) housekeeping genes confirmed that the strains are positioned in two distinct clades. Comparison with intergenic transcribed spacer sequences of type strains of described species of the genus Bradyrhizobium showed similarity lower than 93.1 %, and differences were confirmed by BOX-PCR analysis. Nucleotide identity of three housekeeping genes with type strains of described species ranged from 88.1 to 96.2 %. Average nucleotide identity of genome sequences showed values below the threshold for distinct species of the genus Bradyrhizobium ( < 90.6 %), and the value between the two strains was also below this threshold (91.2 %). Analysis of nifH and nodC gene sequences positioned the two strains in a clade distinct from other species of the genus Bradyrhizobium. Morphophysiological, genotypic and genomic data supported the description of two novel species in the genus Bradyrhizobium, Bradyrhizobium tropiciagri sp. nov. (type strain CNPSo 1112T = SMS 303T = BR 1009T = SEMIA 6148T = LMG 28867T) and Bradyrhizobium embrapense sp. nov. (type strain CNPSo 2833T = CIAT 2372T = BR 2212T = SEMIA 6208T = U674T = LMG 2987).


2007 ◽  
Vol 57 (12) ◽  
pp. 2770-2776 ◽  
Author(s):  
Rachel E. Muir ◽  
Man-Wah Tan

A yellow-pigmented, Gram-positive, aerobic, non-motile, non-spore-forming, irregular rod-shaped bacterium (strain TAN 31504T) was isolated from the bacteriophagous nematode Caenorhabditis elegans. Based on 16S rRNA gene sequence similarity, DNA G+C content of 69.5 mol%, 2,4-diaminobutyric acid in the cell-wall peptidoglycan, major menaquinone MK-11, abundance of anteiso- and iso-fatty acids, polar lipids diphosphatidylglycerol and phosphatidylglycerol and a number of shared biochemical characteristics, strain TAN 31504T was placed in the genus Leucobacter. DNA–DNA hybridization comparisons demonstrated a 91 % DNA–DNA relatedness between strain TAN 31504T and Leucobacter chromiireducens LMG 22506T indicating that these two strains belong to the same species, when the recommended threshold value of 70 % DNA–DNA relatedness for the definition of a bacterial species by the ad hoc committee on reconciliation of approaches to bacterial systematics is considered. Based on distinct differences in morphology, physiology, chemotaxonomic markers and various biochemical characteristics, it is proposed to split the species L. chromiireducens into two novel subspecies, Leucobacter chromiireducens subsp. chromiireducens subsp. nov. (type strain L-1T=CIP 108389T=LMG 22506T) and Leucobacter chromiireducens subsp. solipictus subsp. nov. (type strain TAN 31504T=DSM 18340T=ATCC BAA-1336T).


2004 ◽  
Vol 50 (4) ◽  
pp. 291-297 ◽  
Author(s):  
Michael F Cohen ◽  
Xiang Y Han ◽  
Mark Mazzola

Four phenotypically similar bacterial strains isolated from fungal, plant, and human sources were identified as Azospirillum species. Strains RC1 and LOD4 were isolated from the mycelium of the apple root pathogen Rhizoctonia solani AG 5 and from the rhizosphere of wheat grown in apple orchard soil, respectively. Strains C610 and F4626 isolated from human wounds were previously misclassified as Roseomonas genomospecies 3 and 6. All four strains demonstrated close similarities in 16S rRNA gene sequences, having [Formula: see text]97% identity to Azospirillum brasilense type strain ATCC 29145 and <90% identity to Roseomonas gilardii, the Roseomonas type strain. Extensive phenotypic similarities among the four strains included the ability of free-living cells to fix N2. Cells of strains RC1, LOD4, and C610 but not of strain F4626 could be induced to flocculate by incubation with 10 mmol·L–1glycerol or fructose in medium containing 0.5 mmol·L–1NO3–. Our results indicate a wide range of potential sources for Azospirillum spp. with the isolation of Azospirillum spp. from human wounds warranting further investigation.Key words: Azospirillum brasilense, Roseomonas fauriae, flocculation, Rhizoctonia solani.


2007 ◽  
Vol 57 (3) ◽  
pp. 548-551 ◽  
Author(s):  
Hang-Yeon Weon ◽  
Byung-Yong Kim ◽  
Min-Kyeong Kim ◽  
Seung-Hee Yoo ◽  
Soon-Wo Kwon ◽  
...  

Two bacterial strains, designated GH34-4T and GH41-7T, were isolated from greenhouse soil cultivated with cucumber. The bacteria were strictly aerobic, Gram-negative, rod-shaped and oxidase- and catalase-positive. 16S rRNA gene sequence analysis indicated that these strains belong to the genus Lysobacter within the Gammaproteobacteria. Strain GH34-4T showed highest sequence similarity to Lysobacter yangpyeongensis GH19-3T (97.5 %) and Lysobacter koreensis Dae16T (96.4 %), and strain GH41-7T showed highest sequence similarity to Lysobacter antibioticus DSM 2044T (97.5 %), Lysobacter enzymogenes DSM 2043T (97.5 %) and Lysobacter gummosus ATCC 29489T (97.4 %). Levels of DNA–DNA relatedness indicated that strains GH34-4T and GH41-7T represented species clearly different from L. yangpyeongensis, L. antibioticus, L. enzymogenes and L. gummosus. The major cellular fatty acids of strains GH34-4T and GH41-7T were iso-C16 : 0, iso-C15 : 0 and iso-C17 : 1 ω9c, and the major isoprenoid quinone was Q-8. The DNA G+C contents of GH34-4T and GH41-7T were 62.5 and 66.6 mol%, respectively. On the basis of the polyphasic taxonomic data presented, it is evident that each of these strains represents a novel species of the genus Lysobacter, for which the names Lysobacter niabensis sp. nov. (type strain GH34-4T=KACC 11587T=DSM 18244T) and Lysobacter niastensis sp. nov. (type strain GH41-7T=KACC 11588T=DSM 18481T) are proposed.


2007 ◽  
Vol 57 (4) ◽  
pp. 708-712 ◽  
Author(s):  
Akihito Endo ◽  
Sanae Okada

Five strains of lactic acid bacteria were isolated from a compost of distilled shochu residue in Japan. The isolates were separated into two groups on the basis of 16S rRNA gene sequence similarity, and two subclusters were formed that comprised micro-organisms closely related to Lactobacillus buchneri, L. diolivorans, L. hilgardii, L. kefiri, L. parabuchneri and L. parakefiri. DNA–DNA relatedness results revealed that the isolates could be separated into two groups, and these groups correlated well with the subclusters generated using the phylogenetic analysis. Moreover, the levels of DNA–DNA relatedness showed clear separation of the two groups from their phylogenetic relatives. Therefore, the two groups represent two novel species, for which the names Lactobacillus farraginis sp. nov. (type strain NRIC 0676T=JCM 14108T=DSM 18382T) and Lactobacillus parafarraginis sp. nov. (type strain NRIC 0677T=JCM 14109T=DSM 18390T) are proposed.


2015 ◽  
Vol 65 (Pt_2) ◽  
pp. 510-515 ◽  
Author(s):  
Abdolrazagh Hashemi Shahraki ◽  
Cengiz Çavuşoğlu ◽  
Emanuele Borroni ◽  
Parvin Heidarieh ◽  
Orhan Kaya Koksalan ◽  
...  

Six strains of a rapidly growing scotochromogenic mycobacterium were isolated from pulmonary specimens of independent patients. Biochemical and cultural tests were not suitable for their identification. The mycolic acid pattern analysed by HPLC was different from that of any other mycobacterium. Genotypic characterization, targeting seven housekeeping genes, revealed the presence of microheterogeneity in all of them. Different species were more closely related to the test strains in various regions: the type strain of Mycobacterium moriokaense showed 99.0 % 16S rRNA gene sequence similarity, and 91.5–96.5 % similarity for the remaining six regions. The whole genome sequences of the proposed type strain and that of M. moriokaense presented an average nucleotide identity (ANI) of 82.9 %. Phylogenetic analysis produced poorly robust trees in most genes with the exception of rpoB and sodA where Mycobacterium flavescens and Mycobacterium novocastrense were the closest species. This phylogenetic relatedness was confirmed by the tree inferred from five concatenated genes, which was very robust. The polyphasic characterization of the test strains, supported by the ANI value, demonstrates that they belong to a previously unreported species, for which the name Mycobacterium celeriflavum sp. nov. is proposed. The type strain is AFPC-000207T ( = DSM 46765T = JCM 18439T).


2011 ◽  
Vol 61 (7) ◽  
pp. 1667-1670 ◽  
Author(s):  
M. Tseng ◽  
H. C. Liao ◽  
W. P. Chiang ◽  
G. F. Yuan

A novel actinomycete, designated strain 06182M-1T, was isolated from a mangrove soil sample collected from Chiayi County in Taiwan. Phylogenetic analysis based on 16S rRNA gene sequences revealed levels of similarity of 97.0–98.8 % to the type strains of recognized species of the genus Isoptericola. Chemotaxonomic data also supported the placement of strain 06182M-1T within the genus Isoptericola. However, the low levels of DNA–DNA relatedness between the novel strain and the type strains of recognized species of the genus Isoptericola, in combination with differential phenotypic data, demonstrate that strain 06182M-1T represents a novel species of the genus Isoptericola, for which the name Isoptericola chiayiensis sp. nov. is proposed. The type strain is 06182M-1T ( = BCRC 16888T  = KCTC 19740T).


2004 ◽  
Vol 54 (1) ◽  
pp. 183-189 ◽  
Author(s):  
Mei-Chin Lai ◽  
Chih-Chien Lin ◽  
Ping-Hung Yu ◽  
Yi-Feng Huang ◽  
Sheng-Chung Chen

Three novel halotolerant, hydrogenotrophic methanogens, designated strains K1F9705bT, K1F9705c and O1F9704a, were isolated from an estuary in Eriln Shi, Taiwan, and from a nearby marine water aquaculture fishpond. These isolates were irregular cocci that stained Gram-negative. Strains K1F9705bT and K1F9705c were non-motile, but strain O1F9704a was weakly motile with flagella. They were able to use formate and H2/CO2 to form methane, but they could not catabolize acetate, methanol, trimethylamine or secondary alcohols. Acetate was required for cell growth. Tungsten greatly stimulated the growth of strains K1F9705bT and K1F9705c, but did not affect the growth of strain O1F9704a. Optimal pH and temperature for growth of these three isolates were respectively 7·2 and 37 °C. Optimal NaCl concentration for growth was 0·5 % for strain O1F9704a and 1·0 % for strains K1F9705c and K1F9705bT. Moreover, all strains grew well at up to 8–12 % NaCl. Analysis of the 16S rRNA gene revealed that these isolates are members of the genus Methanocalculus, but are distinct from Methanocalculus taiwanensis, Methanocalculus pumilus and Methanocalculus halotolerans, with sequence similarities of 98·4, 98·3 and 98·2 %, respectively. In addition, strain K1F9705bT possessed 85, 80, 37, 29 and 10 % DNA–DNA relatedness to strain K1F9705c, strain O1F9704a, M. pumilus, M. halotolerans and M. taiwanensis, respectively. Analysis of protein profiles and the M r of surface (S)-layer glycoprotein subunits showed that these three new isolates are closely related to, but distinct from, known Methanocalculus species. A novel species, Methanocalculus chunghsingensis sp. nov., is proposed for strains K1F9705bT, K1F9705c and O1F9704a. The type strain is K1F9705bT (=OCM 772T=DSM 14646T).


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