Gemella parahaemolysans sp. nov. and Gemella taiwanensis sp. nov., isolated from human clinical specimens

Abstract

Four Gram-staining-positive, catalase-negative, coccoid isolates, designated NTUH_1465T, NTUH_2196, NTUH_4957 and NTUH_5572T, were isolated from human specimens. The four isolates displayed more than 99.6 % 16S rRNA gene sequence similarity with Gemella haemolysans ATCC 10379T, and 96.7 to 98.6 % similarity with Gemella sanguinis ATCC 700632T, Gemella morbillorum ATCC 27824T or Gemella cuniculi CCUG 42726T. However, phylogenetic analysis of concatenated sequences of three housekeeping genes, groEL, rpoB and recA, suggested that the four isolates were distinct from G. haemolysans ATCC 10379T and other species. Isolates NTUH_2196, NTUH_4957 and NTUH_5572T clustered together and formed a stable monophyletic clade. DNA–DNA hybridization values among strains NTUH_1465T and NTUH_5572T and their phylogenetically related neighbours were all lower than 49 %. The four isolates could be distinguished from G. haemolysans and other species by phenotypic characteristics. Based on the phylogenetic and phenotypic results, two novel species Gemella parahaemolysans sp. nov. (type strain NTUH_1465T = BCRC 80365T = JCM 18067T) and Gemella taiwanensis sp. nov. (type strain NTUH_5572T = BCRC 80366T = JCM 18066T) are proposed.