Fig. 6. Phylogenetic analysis of Sheffield emm4 genomes collected in 2022–2023 and 2016–2017, within the context of global emm4 isolates. A maximum likelihood phylogenetic tree was generated with the core gene alignment (excluding prophage and SpyCI regions) to reference strain MGAS10750 (GenBank CP000262.1 [63]). The position of another reference strain MEW427 (GenBank CP014138.1 [67]) is also indicated. Alongside our Sheffield emm4 genomes from 2022–2023 and 2016–2017, we included publicly available emm4 genome data from Sheffield, 2019 (n=9) [28]; the UK, 2011–2016 (n=176) [31,55, 56, 59]; the Netherlands, 2009–2022 (n=66) [42]; and the USA, 2015–2017 (n=204) [38,62]. The large grey shaded area indicates the ‘Degraded’ lineage, and the small grey shaded area indicates the M4_NL22 lineage. The scale bar represents the number of nucleotide substitutions per site.