Halococcus qingdaonensis sp. nov., a halophilic archaeon isolated from a crude sea-salt sample

Open Access
Publisher Website
Google Scholar
Abstract
A Gram-negative, extremely halophilic, coccoid archaeal strain, CM5T, was isolated from a crude sea-salt sample collected near Qingdao, China. The organism grew optimally at 35–40 °C and pH 6.0 in the presence of 20 % (w/v) NaCl. Its colonies were red in colour and it could use glucose as a sole carbon source for growth. The 16S rRNA gene sequence of CM5Twas most closely related to those ofHalococcusspecies. Its pattern of antibiotic susceptibility was similar to those of other describedHalococcusspecies. Biochemical tests revealed no sign of H2S production or gelatin liquefaction. The main polar lipids of strain CM5Twere phosphatidylglycerol, phosphatidylglycerol methylphosphate and sulfated diglycosyl diether. No phosphatidylglycerol sulfate was present. The DNA G+C content of strain CM5Twas 61.2 mol% and it gave DNA–DNA reassociation values of 33.7, 57.1 and 29.6 %, respectively, withHalococcus salifodinaeDSM 8989T,Halococcus dombrowskiiDSM 14522TandHalococcus morrhuaeATCC 17082T. Based on its morphological and chemotaxonomic properties and phylogenetic analysis of 16S rRNA gene sequence data, we propose that CM5Tshould be classified within a novel species,Halococcus qingdaonensissp. nov., with strain CM5T(=CGMCC 1.4243T=JCM 13587T) as the type strain.