Development of Mycoplasma synoviae (MS) core genome multilocus sequence typing (cgMLST) scheme

Area of Science:

• Veterinary Microbiology
• Genomics
• Epidemiology

Background:

• Mycoplasma synoviae (MS) is an increasingly prevalent and virulent poultry pathogen.
• Accurate MS strain identification is crucial for disease control and outbreak investigations.
• Existing multilocus sequence typing (MLST) schemes lack sufficient resolution for detailed epidemiological studies.

Purpose of the Study:

• To develop and validate a standardized core genome multilocus sequence typing (cgMLST) scheme for Mycoplasma synoviae.
• To establish a reproducible whole genome sequencing-based typing method for MS.
• To assess the discriminatory power of cgMLST compared to conventional MLST schemes.

Main Methods:

• Identification of 302 core genome genes from 25 diverse MS whole genome sequences.
• Application of the developed cgMLST scheme to type 44 MS isolates from six countries.
• Phylogenetic analysis of cgMLST data and comparison with core genome SNP analysis and epidemiological information.

Main Results:

• The cgMLST scheme targets 302 core genes, representing 35.5% of the MS genome.
• cgMLST phylogenetic trees showed high concordance with SNP-based analysis and epidemiological data.
• cgMLST demonstrated superior discriminatory power, differentiating isolates within the same conventional MLST type.

Conclusions:

• cgMLST provides a standardized, accurate, and highly discriminatory method for typing Mycoplasma synoviae isolates.
• The scheme enables reproducible strain differentiation and facilitates global data sharing through a stable nomenclature.
• cgMLST significantly enhances the capability for poultry disease outbreak investigations and epidemiological surveillance.