Promiscuous evolution of Group A Streptococcal M and M-like proteins

Hannah Frost (1, 2) , Julien Guglielmini (3) , Sebastian Duchêne (4) , Jake Lacey (4) , Martina Sanderson-Smith (5) , Andrew Steer (2, 6) , Mark Walker (7) , Anne Botteaux (1) , Mark Davies (4) , Pierre Smeesters (1, 2, 6)

1 ULB - Université libre de Bruxelles
2 MCRI - Murdoch Children's Research Institute
3 Hub Bioinformatique et Biostatistique - Bioinformatics and Biostatistics HUB
4 The Peter Doherty Institute for Infection and Immunity [Melbourne]
5 University of Wollongong [Australia]
6 University of Melbourne
7 UQ [All campuses : Brisbane, Dutton Park Gatton, Herston, St Lucia and other locations] - The University of Queensland

Group A Streptococcus (GAS) M and M-like proteins are essential virulence factors and represent the primary epidemiological marker of this pathogen. Protein sequences encoding 1054 M, Mrp and Enn proteins, from 1668 GAS genomes, were analysed by SplitsTree4, partitioning around medoids and co-occurrence. The splits network and groups-based analysis of all M and M-like proteins revealed four large protein groupings, with multiple evolutionary histories as represented by multiple edges for most splits, leading to ‘M-family-groups’ (FG) of protein sequences: FG I, Mrp; FG II, M protein and Protein H; FG III, Enn; and FG IV, M protein. M and Enn proteins formed two groups with nine sub-groups and Mrp proteins formed four groups with ten sub-groups. Discrete co-occurrence of M and M-like proteins were identified suggesting that while dynamic, evolution may be constrained by a combination of functional and virulence attributes. At a granular level, four distinct family-groups of M, Enn and Mrp proteins are observable, with Mrp representing the most genetically distinct of the family-group of proteins. While M and Enn protein families generally group into three distinct family-groups, horizontal and vertical gene flow between distinct GAS strains is ongoing.

Mots clés: Streptococcus pyogenes; Typing; Virulence; Vaccine; Surface protein; MGA regular

Domaines: Microbiologie et Parasitologie

Hannah Frost, Julien Guglielmini, Sebastian Duchêne, Jake Lacey, Martina Sanderson-Smith, et al.. Promiscuous evolution of Group A Streptococcal M and M-like proteins. Microbiology, 2023, 169 (1), pp.001280. ⟨10.1099/mic.0.001280⟩. ⟨pasteur-03965799⟩