Enterobacter hormaechei subsp. hoffmannii subsp. nov., Enterobacter hormaechei subsp. xiangfangensis comb. nov., Enterobacter roggenkampii sp. nov., and Enterobacter muelleri is a later heterotypic synonym of Enterobacter asburiae based on computational analysis of sequenced Enterobacter genomes.

<ns4:p> <ns4:bold>Background:</ns4:bold> The predominant species in clinical <ns4:italic>Enterobacter</ns4:italic> isolates is <ns4:italic>E. hormaechei</ns4:italic> . Many articles, clinicians, and GenBank submissions misname these strains as <ns4:italic>E. cloacae</ns4:italic> . The lack of sequenced type strains or named species/subspecies for some clades in the <ns4:italic>E. cloacae</ns4:italic> complex complicate the issue. </ns4:p> <ns4:p> <ns4:bold>Methods:</ns4:bold> The genomes of the type strains for <ns4:italic>Enterobacter hormaechei</ns4:italic> subsp. <ns4:italic>oharae</ns4:italic> , <ns4:italic>E</ns4:italic> . <ns4:italic>hormaechei</ns4:italic> subsp. <ns4:italic>steigerwaltii</ns4:italic> , and <ns4:italic>E. xiangfangensis</ns4:italic> , and two strains from Hoffmann clusters III and IV of the <ns4:italic>E. cloacae</ns4:italic> complex were sequenced. These genomes, the <ns4:italic>E</ns4:italic> . <ns4:italic>hormaechei</ns4:italic> subsp. <ns4:italic>hormaechei</ns4:italic> type strain, and other available <ns4:italic>Enterobacter</ns4:italic> type strains were analysed in conjunction with all extant <ns4:italic>Enterobacter</ns4:italic> genomes in NCBI’s RefSeq using Average Nucleotide Identity (ANI). </ns4:p> <ns4:p> <ns4:bold>Results:</ns4:bold> There were five recognizable subspecies of <ns4:italic>E. hormaechei</ns4:italic> : <ns4:italic>E. hormaechei</ns4:italic> subsp. <ns4:italic>hoffmannii</ns4:italic> subsp. nov., <ns4:italic>E. hormaechei</ns4:italic> subsp. <ns4:italic>xiangfangensis</ns4:italic> comb. nov., and the three previously known subspecies. One of the strains sequenced from the <ns4:italic>E. cloacae</ns4:italic> complex was not a novel <ns4:italic>E. hormaechei</ns4:italic> subspecies but rather a member of a clade of a novel species: <ns4:italic>E. roggenkampii</ns4:italic> sp. nov.. <ns4:italic>E. muelleri</ns4:italic> was determined to be a later heterotypic synonym of <ns4:italic>E. asburiae</ns4:italic> which should take precedence. </ns4:p> <ns4:p> <ns4:bold>Conclusion:</ns4:bold> The phylogeny of the <ns4:italic>Enterobacter</ns4:italic> genus, particularly the <ns4:italic>cloacae</ns4:italic> complex, was re-evaluated based on the type strain genome sequences and all other available <ns4:italic>Enterobacter</ns4:italic> genomes in RefSeq. </ns4:p>