Lysobacter concretionis sp. nov., isolated from anaerobic granules in an upflow anaerobic sludge blanket reactor

Abstract

The taxonomic positions of Lysobacter species with validly published names and a novel strain Ko07T, which was newly isolated from an upflow anaerobic sludge blanket reactor treating wastewater from a brewery, were (re)estimated on the basis of results obtained by using a polyphasic taxonomy approach. Phylogenetic inference based on 16S rRNA gene sequences showed that strain Ko07T and all Lysobacter species with validly published names clustered together in a phylogenetic branch within the class ‘Gammaproteobacteria’. The sequence similarity of strain Ko07T to the type strains of established Lysobacter species was in the range 94·9–96·7 %. Ubiquinone Q-8 and branched fatty acids, C11 : 0 iso, C15 : 0 iso, C16 : 0 iso, iso C17 : 1 ω9c and C11 : 0 iso 3OH, predominantly appeared in strain Ko07T as well as in all type strains of the recognized Lysobacter species. The DNA–DNA hybridization values of strain Ko07T with those of recognized Lysobacter species were estimated to be 2–20 %. Despite sharing common taxonomic features in important phenotypic characteristics, such as gliding movement, long-rod shape and proteolytic activity, strain Ko07T could be distinguished from the Lysobacter species with validly published names by its low DNA–DNA hybridization value, a comparatively low DNA G+C content (63·8 mol%), substrate utilization and some physiochemical characteristics. On the basis of the results obtained in this study, it is proposed that strain Ko07T should be classified as representing a novel member of the genus Lysobacter, for which the name Lysobacter concretionis sp. nov. is proposed. The type strain is Ko07T (=KCTC 12205T=DSM 16239T).