Genotyping Mycoplasma hyopneumoniae isolates based on multi-locus sequence typing, multiple-locus variable-number tandem repeat analysis and analysing gene p146.

Mycoplasma hyopneumoniae is a swine pathogen bacterium, causing significant economic losses worldwide. Epidemiological investigations based on molecular typing methods support the prevention and eradication strategies for the control of M. hyopneumoniae, through tracing the spreading of the pathogen. The present study describes the genotyping of 44 M. hyopneumoniae strains isolated from Hungarian, Czech and Slovakian porcine lung samples by multi-locus sequence typing (MLST), multiple-locus variable-number tandem repeat analysis (MLVA) and analysing gene p146, and the evaluation of the used methods. The resolution of the three-gene (adk, rpoB, tpiA) and the seven-gene (efp, metG, pgiB, recA, adk, rpoB, tpiA) based MLST systems was identical with 27 sequence types. MLVA utilising loci P97-RR1 and Locus1 extended with the serine repeat numbers of gene p146 showed the highest resolution power among the studied methods differentiating 40 genotypes. The independent analysis of gene p146 revealed 31 different types among the isolates. High variability of M. hyopneumoniae strains was detected by the used typing methods. The results confirmed that utilization of the minimal MLST is suitable for phylogenetic analyses of M. hyopneumoniae strains. The MLVA method extended with the evaluation of serine repeat numbers of gene p146 is adequate for the resolution of genetic relationships within MLST groups. Examination of the p146 gene is suitable to complement both MLST and MLVA methods in order to refine closer genetic relationships.