Description of Acinetobacter ihumii sp. nov., Microbacterium ihumii sp. nov., and Gulosibacter massiliensis sp. nov., three new bacteria isolated from human blood.

Abstract

Blood is precious tissue that is normally sterile. With the aim of diagnosing the cause of bacteremia, three bacterial strains were isolated from three different individuals. Strains Marseille-P7157T and Marseille-Q2854T are Gram-stain positive, non-spore-forming rod-shaped bacteria, while strain Marseille-P8049T is a Gram-stain negative, motile, non-spore-forming and rod-shaped bacterium. The major fatty acids found (>30%) were hexadecanoic acid for strain Marseille-P8049T and 12-methyl tetradecanoic acid for both strains Marseille-P7157T and Marseille-Q2854T. The 16S rRNA gene sequence analysis shows that strains Marseille-P8049 and Marseille-Q2854T have sequence similarity of 96.8%, 99.04%, and 98.3% with Acinetobacter ursingii strain LUH3792 (NR_025392.1), Gulosibacter faecalis strain B187 (NR_041812.1), and Schaalia canis strain CCUG 41706 (NR_025366.1), respectively. In addition, strains Marseille-Q2854T, Marseille-P8049T and Marseille-P7157T shared with their closely related species cited above the following DDH values: 19.5%, 24.4%, and 20.2%, respectively. Based on these phenotypic and genomic findings, we consider that strains Marseille-P8049T (= CSUR P8049 = CECT 30350), Marseille-P2854T ( = CSUR Q2854 = CECT 30120) and Marseille-P7157T ( = CSUR P7157 = CECT 30048) are new bacterial species, for which the names Acinetobacter ihumii sp. nov., Microbacterium ihumii sp. nov., and Gulosibacter massiliensis sp. nov., are proposed.