{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T06:54:18Z","timestamp":1775804058227,"version":"3.50.1"},"reference-count":47,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T00:00:00Z","timestamp":1775779200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Cell. Infect. Microbiol."],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>\n                      <jats:italic>Streptococcus dysgalactiae<\/jats:italic>\n                      is an important pathogen in both humans and animals. Alpha-like proteins (Alps) are surface-anchored adhesins and contribute to host tissue invasion. While Alps are nearly ubiquitous in\n                      <jats:italic>Streptococcus agalactiae<\/jats:italic>\n                      and are recognized as major virulence factors in\n                      <jats:italic>Streptococcus pyogenes<\/jats:italic>\n                      , their presence and diversity in\n                      <jats:italic>S. dysgalactiae<\/jats:italic>\n                      remain poorly characterized.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      We screened 1,243\n                      <jats:italic>S. dysgalactiae<\/jats:italic>\n                      genomes of human and animal origin from Norway, Japan, Canada, and Australia for presence of\n                      <jats:italic>alp<\/jats:italic>\n                      genes. A subset of 32 strains from Norway was further sequenced using long-read technology (Nanopore) to resolve tandem repeat regions of\n                      <jats:italic>alp<\/jats:italic>\n                      genes.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      By screening global strain collections, we found five novel\n                      <jats:italic>alp<\/jats:italic>\n                      genes, designated here as\n                      <jats:italic>dysalp2\u20135<\/jats:italic>\n                      and\n                      <jats:italic>alp1\u20133 hybrid<\/jats:italic>\n                      . The\n                      <jats:italic>alp<\/jats:italic>\n                      genes exhibited extensive genetic heterogeneity, predominantly arising from mosaicism and tandem repeat variations. Overall,\n                      <jats:italic>alp<\/jats:italic>\n                      genes were detected in 18% of human and 10-15% of animal strains. There were geographic differences in prevalence and diversity of\n                      <jats:italic>alp<\/jats:italic>\n                      genes, yet the overall distribution did not follow a strictly clonal pattern. The\n                      <jats:italic>alp<\/jats:italic>\n                      genes in\n                      <jats:italic>S. dysgalactiae<\/jats:italic>\n                      resided on mobile genetic elements, and we detected similar elements also in other streptococcal species.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>\n                      We reveal that Alpha-like proteins are common and widely distributed among\n                      <jats:italic>S. dysgalactiae<\/jats:italic>\n                      , and exhibit extensive genetic heterogeneity. Our findings expand our understanding of Alp diversity and shed light on the evolutionary mechanisms that drive cross-species exchange of\n                      <jats:italic>alp<\/jats:italic>\n                      genes.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fcimb.2026.1770747","type":"journal-article","created":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T05:58:59Z","timestamp":1775800739000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["The dynamic Alp landscape of Streptococcus dysgalactiae"],"prefix":"10.3389","volume":"16","author":[{"given":"Camilla","family":"Olaisen","sequence":"first","affiliation":[{"name":"Department of Medical Microbiology, St. Olavs Hospital","place":["Trondheim, Norway"]},{"name":"Clinic of Laboratory Medicine, St. Olavs Hospital","place":["Trondheim, Norway"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alba","family":"Kaci","sequence":"additional","affiliation":[{"name":"Center for Laboratory Medicine, \u00d8stfold Hospital Trust","place":["Gr\u00e5lum, Norway"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Christina Gabrielsen","family":"\u00c5s","sequence":"additional","affiliation":[{"name":"Department of Medical Microbiology, St. Olavs Hospital","place":["Trondheim, Norway"]},{"name":"Clinic of Laboratory Medicine, St. Olavs Hospital","place":["Trondheim, Norway"]},{"name":"Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology (NTNU)","place":["Trondheim, Norway"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jan Egil","family":"Afset","sequence":"additional","affiliation":[{"name":"Department of Medical Microbiology, St. Olavs Hospital","place":["Trondheim, Norway"]},{"name":"Clinic of Laboratory Medicine, St. Olavs Hospital","place":["Trondheim, Norway"]},{"name":"Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology (NTNU)","place":["Trondheim, Norway"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Oddvar","family":"Oppegaard","sequence":"additional","affiliation":[{"name":"Department of Clinical Science, Faculty of Medicine, University of Bergen","place":["Bergen, Norway"]},{"name":"Department of Medicine, Haukeland University Hospital","place":["Bergen, Norway"]}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2026,4,10]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"493","DOI":"10.1038\/s41586-024-07487-w","article-title":"Accurate structure prediction of biomolecular interactions with AlphaFold 3","volume":"630","author":"Abramson","year":"2024","journal-title":"Nature"},{"key":"B2","doi-asserted-by":"publisher","first-page":"18245","DOI":"10.1074\/jbc.M412391200","article-title":"Crystal structure of the N-terminal domain of the group B streptococcus alpha C protein","volume":"280","author":"Aup\u00e9rin","year":"2005","journal-title":"J. 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