Clostridium neonatale sp. nov. linked to necrotizing enterocolitis in neonates and a clarification of species assignable to the genus Clostridium (Prazmowski 1880) emend. Lawson and Rainey 2016

A description of an outbreak of necrotizing enterocolitis among neonates, linked to the putative novel species Clostridium neonatale and assignable to the genus Clostridium, was previously reported in brief but that name had never been validly published (Alfa et al. Clin Inf Dis 2002;35:S101-S105). Features of this taxon group and its phylogenetic position with respect to contemporary species in the genus Clostridium were recently reviewed and still found to be unique. Therefore, we provide here a description based on biochemical, chemotaxonomic and antimicrobial susceptibility testing (AST), matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) MS, 16S rRNA gene sequencing as well as information obtained by whole genome sequencing (WGS) for strains 99A005 T and 99A006. Those two C. neonatale strains were essentially identical to each other, with genome sizes of 4 658 596-4 705 520 bp and G+C content of 28.4-28.5 mol% (WGS). AST inferred susceptibility to 14 antibiotics. MALDI-TOF spectra were unique and could potentially be used for identification. The type strain is (NML) LCDC 99A005 T [=ATCC BAA-265 T =CCUG 46077 T =St. Boniface Hospital 30686 T ]. While performing this review, we found that the names of 24 validly published species assignable to the genus Clostridium had been omitted from the emended description of the genus (Lawson and Rainey Int J Syst Evol Microbiol 2016;66 :1009-1016). Those species are listed in brief here. Lastly, based on this review, we also propose that Eubacterium budayi, Eubacterium nitritogenes and Eubacterium combesii be transferred to the emended genus Clostridium, as Clostridium budayi comb. nov., Clostridium nitritogenes comb. nov. and Clostridium combesii comb. nov., respectively.