Mycobacterium parakoreense sp nov., a slowly growing non-chromogenic species related to Mycobacterium koreense, isolated from a human clinical specimen

A previously undescribed, slowly growing, non-chromogenic Mycobacterium strain (299(T)) was isolated from the sputum sample of a patient with a symptomatic pulmonary infection. Phenotypically, strain 299(T) was generally similar to Mycobacterium koreense DSM 45576(T) and Mycobacterium triviale ATCC 23292(T). The 16S rRNA gene sequence of strain 299(T) was similar to that of M. koreense DSM 45576(T) (Gen Bank accession no. AY734996, 99.5% similarity); however, it differed substantially from that of M. triviale ATCC 23292(T) (X88924, 98.2%). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain 299(T) clustered together with M. koreense DSM 45576(T) and M. triviale ATCC 23292(T), supported by high bootstrapping values (99%). Unique mycolic acid profiles and phylogenetic analysis based on two different chronometer molecules, the hsp65 and rpoB genes, strongly supported the taxonomic status of this strain as representing a distinct species. These data support the conclusion that strain 299(T) represents a novel mycobacterial species, for which the name Mycobacterium parakoreense sp. nov. is proposed. The type strain is 299(T) (=DSM 45575(T)=KCTC 19818(T)).