Falsirhodobacter halotolerans gen. nov., sp. nov., isolated from dry soils of a solar saltern

Abstract

Two bacterial strains (JA744T and JA745) were isolated from dry soil samples collected from solar salterns at Humma, Odisha, India. Both strains were Gram-stain-negative, catalase- and oxidase-positive, motile rods. Major fatty acids in both strains included C18 : 1ω7c, C18 : 0 and C16 : 0, while minor amounts of C10 : 0 3-OH, C12 : 0, C12 : 0 3-OH, C14 : 0 and C16 : 0 were also present. Diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, phosphatidylglycerol, an unidentified glycolipid, five unidentified lipids, an unidentified aminolipid and an unidentified phospholipid made up the polar lipids of both strains. Both strains had bacteriohopane derivatives (BHD1,2) and diploptene as major hopanoids. Mean genomic DNA G+C content was 75±1 mol% and the two strains were closely related (mean DNA–DNA hybridization >90 %). Phylogenetic analysis based on the 16S rRNA gene sequence showed that the two strains clustered with species of the genus Rhodobacter belonging to the family Rhodobacteraceae of the class Alphaproteobacteria . The highest sequence similarity was observed with Rhodobacter sphaeroides ATH2.4.1T (96 %) and other members of the genera Rhodobacter and Pseudorhodobacter (<96 %). However, the two strains were positioned distinctly outside the group formed by the other genera of the family Rhodobacteraceae . Distinct morphological, physiological and genotypic differences from previously described taxa support the classification of these isolates as representatives of a novel species in a new genus, for which the name Falsirhodobacter halotolerans gen. nov., sp. nov. is proposed. The type strain of Falsirhodobacter halotolerans is JA744T ( = KCTC 32158T = NBRC 108897T).

Sphingopyxis contaminans sp. nov., isolated from a contaminated Petri dish

“…Quinones were analysed by Shimadzu after extraction with a chloroform/methanol (2 : 1, v/v) mixture and purified by TLC (Subhash et al, 2013a). Q-10 (.90 %) was the major quinone of strain JC216 T , S. wooponensis KCTC 23340 T and S. rigui KCTC 23326 T .…”

“…Cellular fatty acids were methylated, separated and identified as previously described (Subhash et al, 2013a). C 18 : 1 v7c/ C 18 : 1 v6c, C 16 : 1 v7c/C 16 : 1 v6c, C 14 : 0 2-OH and C 16 : 0 were the major (¢8 %) fatty acids of strain JC216 T with minor amounts of C 12 : 0 , C 15 : 0 2-OH, C 16 : 0 2-OH, C 16 : 1 2-OH, C 17 : 1 v6c, C 17 : 1 v8c and C 17 : 1 v9c.…”

“…Members of the genus Sphingopyxis are Gram-stain-negative, non-spore-forming, yellow to brown pigmented and contain sphingoglycolipids (Yoon et al, 2005). In this study, we isolated a strain (JC216 T ) which had clear distinguishing characteristics from the type strains of species of the genus Sphingopyxis.Strain JC216 T was isolated in March 2013, from a contaminated Petri dish from our laboratory (GPS position; 17 u 279 20.6199 N 78 u 199 0099 E) while growing a strain of the genus Pontibacter on agar medium (Subhash et al, 2013a) containing (g l 21 ): KH 2 PO 4 (0.2), NaCl (1), NH 4 Cl (0.25), KCl (0.5), CaCl 2 . 2H 2 0 (0.15), MgCl 2 .…”

“…Strain JC216 T was isolated in March 2013, from a contaminated Petri dish from our laboratory (GPS position; 17 u 279 20.6199 N 78 u 199 0099 E) while growing a strain of the genus Pontibacter on agar medium (Subhash et al, 2013a) containing (g l 21 ): KH 2 PO 4 (0.2), NaCl (1), NH 4 Cl (0.25), KCl (0.5), CaCl 2 . 2H 2 0 (0.15), MgCl 2 .…”

“…Cell material for 16S rRNA gene sequencing was taken from an isolated colony. DNA was extracted, purified, PCR-amplified and sequenced as previously described (Subhash et al, 2013a). Identification of phylogenetic neighbours and calculation of pairwise 16S rRNA gene sequence similarity was achieved using the EzTaxon-e server (Kim et al, 2012).…”