Simulacricoccus ruber gen. nov., sp. nov., a microaerotolerant, non-fruiting, myxospore-forming soil myxobacterium and emended description of the family Myxococcaceae

Abstract

A non-fruiting group of myxobacteria was previously speculated to exist in nature based on metagenomics data containing uncultured members of the order Myxococcales. Here, we describe a myxobacterial strain, designated MCy10636T , which was isolated from a German soil sample collected in 2013. It exhibits swarming characteristics but atypically produces myxospores in the absence of fruiting bodies. The novel strain stains Gram-negative and Congo-red-negative and is characterized mesophilic, neutrophilic, chemoheterotrophic and microaerotolerant. Branched-chain fatty acids are the predominant cellular fatty acids over the straight-chain type, and contain the major fatty acids iso-C17 : 0 2-OH, C16 : 1, isoC17 : 0 and iso-C15 : 0. Based on BLASTn results, the 16S rRNA gene sequence reveals similarity (97 %) to Aggregicoccus edonensis MCy1366T , (97 %) Myxococcus macrosporus DSM 14697T , (96 %) Corallococcus coralloides DSM2259T and Corallococcus exiguus Cc e167T . Phylogenetic analysis showed a novel lineage of MCy10636T in the family Myxococcaceae, suborder Cystobacterineae. Based on polyphasic taxonomic characterization, we propose that this unusual, non-fruiting, myxospore-forming and microaerotolerant myxobacterial strain, MCy10636T , represents a novel genus and species, Simulacricoccus ruber gen. nov., sp. nov. (DSM 106554T =NCCB 100651T ).