Description of Klebsiella grimontii sp. nov.

Strains previously identified as Klebsiella oxytocaphylogroup Ko6 were characterized by rpoB, gyrA and rrs gene sequencing, genome-sequence based average nucleotide identity analysis and their biochemical characteristics. rpoB and gyrA sequencing demonstrated that the Ko6 strains formed a well-demarcated sequence cluster related to, but distinct from, Klebsiella oxytoca (which includes strains previously labelled as K. oxytocaphylogroup Ko2) and Klebsiella michiganensis (Ko1). The average nucleotide identity values of Ko6 with K. oxytoca and K. michiganensis were 91.2 and 93.47 %, respectively. The inability to metabolize melezitose differentiated most of the Ko6 strains from K. oxytoca and K. michiganensis. Based on its genetic and phenotypic characteristics, we propose the name Klebsiella grimontii for the Ko6 sequence cluster, with strain 06D021T (=CIP111401T, DSM 105630T) as the type strain. Strains of Klebsiella grimontii were isolated from human blood cultures, wound infections, antibiotic-associated haemorrhagic colitis and faecal carriage.