Mitsuaria chitinivorans sp. nov. a potential candidate for bioremediation: emended description of the genera Mitsuaria, Roseateles and Pelomonas.

As a part of studying the effect of deoxygenation, eutrophication and acidification on bacterial diversity, strain HWN-4T was isolated from tube well water and characterized. The draft genome sequencing of strain HWN-4T revealed a genome size of 5,774,764 bp and the annotation indicated 5102 coding sequences including 66 RNA genes. Strain HWN-4T is Gram negative, rod-shaped, motile in the log phase, catalase and oxidase positive, and the major fatty acids and respiratory quinone present are C10:0 3-OH, C14:0 3OH/C16:1 iso I, C16:1 ω7c/C16:1 ω6c, C16:0 and C17:0 cyclo and ubiquinone-8, respectively. The phylogenetic analyses, based on 16S rRNA gene sequence, indicated that strain HWN-4T is a member of the genus Mitsuaria. The average nucleotide identity (ANI) and genome-to-genome similarity between strain HWN-4T and all other species/strains of the genus Mitsuaria are less than (%) 95.0 and 70.0, respectively. This confirms the status of strain HWN-4T as a novel species. The species status is further confirmed by phenotypic differences exhibited by strain HWN-4T with other members of the same genus. Based on the collective differences exhibited by strain HWN-4T with other members of the genus Mitsuaria, the name Mitsuaria chitinivorans sp. nov. is proposed. Further, the diagnostic signature nucleotides were identified in the 16S rRNA gene sequences of members of the genera Mitsuaria, Pelomonas and Roseateles, that distinctly differentiate them and support an emendation of the genera. Besides, phylogenetic and structural characterization of chitinases from members of the genus Mitsuaria was performed. The type strain of Mitsuaria chitinivorans sp. nov. is HWN-4T = LMG 28685T = KTCC 42483T.

Emended description of the family Chromatiaceae, phylogenetic analyses of the genera Alishewanella, Rheinheimera and Arsukibacterium, transfer of Rheinheimera longhuensis LH2-2T to the genus Alishewanella and description of Alishewanella alkalitolerans sp. nov. from Lonar Lake, India.

Phylogenetic analyses were performed for members of the family Chromatiaceae, signature nucleotides deduced and the genus Alishewanella transferred to Chromatiaceae. Phylogenetic analyses were executed for the genera Alishewanella, Arsukibacterium and Rheinheimera and the genus Rheinheimera is proposed to be split, with the creation of the Pararheinheimera gen. nov. Furthermore, the species Rheinheimera longhuensis, is transferred to the genus Alishewanella as Alishewanella longhuensis comb. nov. Besides, the genera Alishewanella and Rheinheimera are also emended. Strain LNK-7.1T was isolated from a water sample from the Lonar Lake, India. Cells were Gram-negative, motile rods, positive for catalase, oxidase, phosphatase, contained C16:0, C17:1ω8c, summed feature3 (C16:1ω6c and/or C16:1ω7c) and summed feature 8 (C18:1ω7c) as major fatty acids, PE and PG as the major lipids and Q-8 as the sole respiratory quinone. Phylogenetic analyses using NJ, ME, ML and Maximum parsimony, based on 16S rRNA gene sequences, identified Alishewanella tabrizica RCRI4T as the closely related species of strain LNK-7.1T with a 16S rRNA gene sequence similarity of 98.13%. The DNA-DNA similarity between LNK-7.1T and the closely related species (A. tabrizica) was only 12.0% and, therefore, strain LNK-7.1T was identified as a novel species of the genus Alishewanella with the proposed name Alishewanella alkalitolerans sp. nov. In addition phenotypic characteristics confirmed the species status to strain LNK-7.1T. The type strain of A. alkalitolerans is LNK-7.1T (LMG 29592T = KCTC 52279T), isolated from a water sample collected from the Lonar lake, India.

Description of Deinococcus oregonensis sp. nov., from biological soil crusts in the Southwestern arid lands of the United States of America.

Biological soil crusts are distinct habitats, harbor unique prokaryotic diversity and gave an impetus to isolate novel species. In the present study, a pink-pigmented bacterium, (OR316-6T), was isolated from biological soil crusts using oligotrophic BG11-PGY medium. Strain OR316-6T was Gram-positive, short rods, non-motile and non-spore forming. Cells were positive for catalase, oxidase and ß-galactosidase and negative for most of the enzymatic activities. The major fatty acids present were C16:0, C17:0, and C16:1ω7c and contained MK-8 and MK-10 as the predominant menaquinones. The cell wall peptidoglycan was of A3ß variant with L-ornithine as the diamino acid. Based on the above characteristics, strain OR316-6T was assigned to the genus Deinococcus. The phylogenetic analysis indicated that strain OR316-6T was closely related to D. aquatilis DSM 23025T with a 16S rRNA gene similarity of 99.3 % and clustered with a bootstrap value of 100 %. DNA-DNA similarity between strain OR316-6T and D. aquatilis DSM 23025T was 37.0 % indicating that strain OR316-6T was a novel species. Further, DNA fingerprinting of stains OR316-6T and D. aquatilis DSM 23035T demonstrated that both strains were related to each other with a similarity coefficient of only 0.32 and supported the species status to strain OR316-6T. In addition, phenotypic characteristics distinguished strain OR316-6T from D. aquatilis DSM 23025T. Based on the cumulative differences, strain OR316-16T exhibited with its closely related species, it was identified as a novel species and proposed the name Deinococcus oregonensis sp. nov. The type strain is D. oregonensis sp. nov. (OR316-6T = JCM 13503T = DSM 17762T).

Description of Hydrogenophaga laconesensis sp. nov. isolated from tube well water.

A light cream color colony was isolated, using oligotrophic LB agar medium, from a water sample collected from a tube well and designated as HWB-10(T). Cells of strain HWB-10(T) were Gram-negative, motile rods, non-spore forming, positive for catalase, oxidase, nitrate reduction and esculin. The predominant fatty acids were C16:0, summed feature 4 (C16:1 ω7c/iso-C15:0 2-OH) and summed feature 7 (C18:1 ω7c, C18:1 ω9t and/or C18:1 ω12t), and the major ubiquinone was Q-8. NCBI-BLAST- and EzTaxon-based 16S rRNA gene sequence similarity search identified strain HWB-10(T) as a member of the genus Hydrogenophaga and H. atypica DSM 15342(T), H. defulvi DSM 15341(T), H. palleronii LMG2366(T) and H. taeniospiralis LMG7170(T) being the nearest phylogenetic species with a similarity (%) of 99.3, 99.1, 98.4 and 98.2, respectively, while the similarity was <98.0 % with other species of the genus. However, DNA-DNA similarities between HWB-10(T) and H. atypica DSM 15342(T) and H. defulvi DSM 15341(T) were 37.0 and 43.0 %, respectively, indicating that strain HWB-10(T) is a novel species. Further, the DNA fingerprinting, based on BOX-, ERIC-, (GTG)5- and REP-PCR amplifications, distinguished strain HWB-10(T) from its closest species, H. atypica DSM 15342(T) and H. defulvi DSM 15341(T) with similarity coefficients of 0.45 and 0.37, respectively, a value sufficient to establish the species status within the genus Hydrogenophaga. In addition, strain HWB-10(T) exhibited several phenotypic differences with its closely related species. Based on the above cumulative differentiating characteristics, strain HWB-10(T) was identified as a new species of the genus Hydrogenophaga and proposed as Hydrogenophaga laconesensis sp. nov. with strain HWB-10(T) (KTCC 42478(T) = LMG 28681(T)) as its type strain.

Response of bacterioplankton to iron fertilization of the Southern Ocean, Antarctica.

Ocean iron fertilization is an approach to increase CO2 sequestration. The Indo-German iron fertilization experiment "LOHAFEX" was carried out in the Southern Ocean surrounding Antarctica in 2009 to monitor changes in bacterial community structure following iron fertilization-induced phytoplankton bloom of the seawater from different depths. 16S rRNA gene libraries were constructed using metagenomic DNA from seawater prior to and after iron fertilization and the clones were sequenced for identification of the major bacterial groups present and for phylogenetic analyses. A total of 4439 clones of 16S rRNA genes from ten 16S rRNA gene libraries were sequenced. More than 97.35% of the sequences represented four bacterial lineages i.e. Alphaproteobacteria, Gammaproteobacteria, Bacteroidetes, and Firmicutes and confirmed their role in scavenging of phytoplankton blooms induced following iron fertilization. The present study demonstrates the response of Firmicutes due to Iron fertilization which was not observed in previous southern ocean Iron fertilization studies. In addition, this study identifies three unique phylogenetic clusters LOHAFEX Cluster 1 (affiliated to Bacteroidetes), 2, and 3 (affiliated to Firmicutes) which were not detected in any of the earlier studies on iron fertilization. The relative abundance of these clusters in response to iron fertilization was different. The increase in abundance of LOHAFEX Cluster 2 and Papillibacter sp. another dominant Firmicutes may imply a role in phytoplankton degradation. Disappearance of LOHAFEX Cluster 3 and other bacterial genera after iron fertilization may imply conditions not conducive for their survival. It is hypothesized that heterotrophic bacterial abundance in the Southern Ocean would depend on their ability to utilize algal exudates, decaying algal biomass and other nutrients thus resulting in a dynamic bacterial succession of distinct genera.

Draft genome of Kocuria polaris CMS 76or(T) isolated from cyanobacterial mats, McMurdo Dry Valley, Antarctica: an insight into CspA family of proteins from Kocuria polaris CMS 76or(T).

Kocuria polaris strain CMS 76or(T) is a gram-positive, orange-pigmented bacterium isolated from a cyanobacterial mat sample from a pond located in McMurdo Dry Valley, Antarctica. It is psychrotolerant, orange pigmented, hydrolyses starch and Tween 80 and reduces nitrate. We report the 3.78-Mb genome of K. polaris strain CMS 76or(T), containing 3416 coding sequences, including one each for 5S rRNA, 23S rRNA, 16S rRNA and 47 tRNA genes, and the G+C content of DNA is 72.8%. An investigation of Csp family of proteins from K. polaris strain CMS 76or(T) indicated that it contains three different proteins of CspA (peg.319, peg.2255 and 2832) and the length varied from 67 to 69 amino acids. The three different proteins contain all the signature amino acids and two RNA binding regions that are characteristic of CspA proteins. Further, the CspA from K. polaris strain CMS 76or(T) was different from CspA of four other species of the genus Kocuria, Cryobacterium roopkundense and E. coli indirectly suggesting the role of CspA of K. polaris strain CMS 76or(T) in psychrotolerant growth of the bacterium.

The community and phylogenetic diversity of biological soil crusts in the Colorado Plateau studied by molecular fingerprinting and intensive cultivation.

We studied the bacterial communities in biological soil crusts (BSCs) from the Colorado Plateau by enrichment and cultivation, and by statistically analyzed denaturing gradient gel electrophoresis (DGGE) fingerprinting of environmental 16S rRNA genes, and phylogenetic analyses. Three 500-m-long transects, tens of km apart, consisting of 10 equally spaced samples each, were analyzed. BSC communities consistently displayed less richness (10-32 detectable DGGE bands per sample) and Shannon diversity (2.1-3.3) than typical soil communities, with apparent dominance by few members. In spite of some degree of small-scale patchiness, significant differences in diversity and community structure among transects was detectable, probably related to the degree of crust successional maturity. Phylogenetic surveys indicated that the cyanobacterium Microcoleus vaginatus was dominant, with M. steenstrupii second among phototrophs. Among the 48 genera of nonphototrophs detected, Actinobacteria (particularly Streptomyces spp.) were very common and diverse, with 18 genera and an average contribution to the total 16S rDNA amplificate of 11.8%. beta-Proteobacteria and Bacteriodetes contributed around 10% each; Low-GC Gram-positives, alpha-Proteobacteria, Thermomicrobiales, and Acidobacteria were common (2-5%). However, the second largest contribution was made by deep-branching unaffiliated alleles (12.6%), with some of them representing candidate bacterial divisions. Many of the novel strains isolated are likely new taxa, and some were representatives of the phylotypes detected in the field. The mucoid or filamentous nature of many of these isolates speaks for their role in crust formation.