A single multilocus sequence typing (MLST) scheme for seven pathogenic Leptospira species

Area of Science:

• Microbiology
• Genetics
• Epidemiology

Background:

• The existing Leptospira multilocus sequence typing (MLST) scheme is limited to two pathogenic species.
• There is a need to expand the MLST scheme to cover more pathogenic Leptospira species.

Purpose of the Study:

• To broaden the utility of the MLST scheme to include seven major pathogenic Leptospira species.
• To develop a robust MLST scheme for accurate species identification and phylogenetic analysis of Leptospira.

Main Methods:

• Modified the existing MLST scheme by replacing the fadD locus with caiB.
• Applied the modified scheme to characterize 325 Leptospira isolates from seven species.
• Performed phylogenetic analysis using concatenated sequences of the seven MLST loci.

Main Results:

• The modified MLST scheme demonstrated comparable discriminatory power to the original scheme.
• Phylogenetic analysis confirmed distinct clades for each of the seven species, with no misclassifications.
• Analysis revealed complex relationships between sequence types and serovars, with 18 sequence types encompassing multiple serovars and 14 serovars containing multiple sequence types.

Conclusions:

• The developed MLST scheme effectively characterizes and assigns species to isolates of seven major pathogenic Leptospira species.
• The updated MLST scheme, supported by a website, facilitates Leptospira identification and epidemiological studies.
• The study provided new insights into the global phylogeography of Leptospira and the utility of MLST in linking human disease to specific hosts.