Development of a multi-locus sequence typing scheme for the molecular typing of Mycoplasma pneumoniae. PHE MYCOPLASMA

Mycoplasma pneumoniae is a major human respiratory pathogen causing both upper and lower respiratory disease in humans of all ages, and can also result in other serious extra-pulmonary sequelae. A multi-locus sequence typing (MLST) scheme for M. pneumoniae was developed, based on the sequence of eight housekeeping genes (ppa, pgm, gyrB, gmk, glyA, atpA, arcC, and adk) and applied to 55 M. pneumoniae clinical isolates and the two type strains M129 and FH. A total of 12 sequence types (STs) resulted for 57 M. pneumoniae isolates tested; with a discriminatory index of 0.21 STs per isolate. The MLST loci used in this scheme were shown to be stable in ten strains following ten sequential sub-culture passages. Phylogenetic analysis of concatenated sequences of the eight loci indicated two distinct genetic clusters which could be directly linked to multi-locus variable-number tandem repeat analysis (MLVA) type. Genetic MLST clustering was confirmed by genomic sequence analysis, indicating that the MLST scheme developed in this study is representative of the genome. Furthermore, this MLST scheme was shown to be more discriminatory than both MLVA and P1 typing for the M. pneumoniae isolates examined, providing a method for further and more detailed analysis of observed epidemic peaks of M. pneumoniae infection. This scheme is supported by a public web-based database (http://pubmlst.org/mpneumoniae)