Mycobacterium paraseoulense sp. nov., a slowly growing, scotochromogenic species related genetically to Mycobacterium seoulense.

A previously unidentified, slowly growing, scotochromogenic Mycobacterium species, represented by strain 31118(T), was discovered during hsp65 sequence-based reidentification of Korean clinical isolates that had been previously identified as Mycobacterium scrofulaceum by conventional biochemical tests. Although the 16S rRNA gene sequence of strain 31118(T) was identical to that of the recently described Mycobacterium seoulense, phylogenetic analyses based on three independent alternative targets (rpoB, hsp65 and the 16S-23S internal transcribed spacer) showed that it was closely related to M. seoulense but was a distinct phylogenetic entity. Furthermore, the phenetic characteristics of this strain were more similar to those of M. scrofulaceum than to those of M. seoulense. Taken together, these results support the conclusion that this strain represents a novel mycobacterium species, for which the name Mycobacterium paraseoulense sp. nov. is proposed. The type strain is 31118(T) (=DSM 45000(T) =KCTC 19145(T)).