{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,11]],"date-time":"2026-04-11T10:41:23Z","timestamp":1775904083443,"version":"3.50.1"},"reference-count":44,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2022,2,7]],"date-time":"2022-02-07T00:00:00Z","timestamp":1644192000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["Norte-01-0145-FEDER-000012"],"award-info":[{"award-number":["Norte-01-0145-FEDER-000012"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["FEDER\/02\/SAICT\/2020\/072560"],"award-info":[{"award-number":["FEDER\/02\/SAICT\/2020\/072560"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biology"],"abstract":"<jats:p>The production of extended-spectrum \u03b2-lactamases (ESBLs) is the main defense mechanism found in Gram negative bacteria. Among all the ESBLs, the CTX-M enzymes appear as the most efficient in terms of dissemination in different epidemiological contexts. CTX-M enzymes exhibit a striking plasticity, with a large number of allelic variants distributed in several sublineages, which can be associated with functional heterogeneity of clinical relevance. This observational analytical study provides an update of this family, currently with more than 200 variants described, from a phylogenetic, molecular, and structural point of view through homology in amino acid sequences. Our data, combined with described literature, provide phylogenetic and structural evidence of a new group. Thus, herein, we propose six groups among CTX-M enzymes: the already stablished CTX-M-1, CTX-M-2, CTX-M-8, CTX-M-9, and CTX-M-25 clusters, as well as CTX-M-151 as the new cluster.<\/jats:p>","DOI":"10.3390\/biology11020256","type":"journal-article","created":{"date-parts":[[2022,2,7]],"date-time":"2022-02-07T08:38:48Z","timestamp":1644223128000},"page":"256","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["New CTX-M Group Conferring \u03b2-Lactam Resistance: A Compendium of Phylogenetic Insights from Biochemical, Molecular, and Structural Biology"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5817-6226","authenticated-orcid":false,"given":"Jacinta","family":"Mendon\u00e7a","sequence":"first","affiliation":[{"name":"LABMI\u2014Laboratory of Medical and Industrial Biotechnology, 4200-374 Porto, Portugal"},{"name":"ESS\u2014Escola Superior de Sa\u00fade, IPP\u2014Porto Polytechnic Institute, 4200-072 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3277-7821","authenticated-orcid":false,"given":"Carla","family":"Guedes","sequence":"additional","affiliation":[{"name":"LABMI\u2014Laboratory of Medical and Industrial Biotechnology, 4200-374 Porto, Portugal"},{"name":"ESS\u2014Escola Superior de Sa\u00fade, IPP\u2014Porto Polytechnic Institute, 4200-072 Porto, Portugal"},{"name":"i3S\u2014Metabesity Research Team, Instituto de Investiga\u00e7\u00e3o e Inova\u00e7\u00e3o em Sa\u00fade, 4200-135 Porto, Portugal"},{"name":"UVIGO\u2014Facultade de Biolog\u00eda, Universidade de Vigo, 36310 Pontevedra, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1711-0858","authenticated-orcid":false,"given":"Carina","family":"Silva","sequence":"additional","affiliation":[{"name":"LABMI\u2014Laboratory of Medical and Industrial Biotechnology, 4200-374 Porto, Portugal"},{"name":"ESS\u2014Escola Superior de Sa\u00fade, IPP\u2014Porto Polytechnic Institute, 4200-072 Porto, Portugal"},{"name":"UVIGO\u2014Facultade de Biolog\u00eda, Universidade de Vigo, 36310 Pontevedra, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1376-2624","authenticated-orcid":false,"given":"Sara","family":"S\u00e1","sequence":"additional","affiliation":[{"name":"LABMI\u2014Laboratory of Medical and Industrial Biotechnology, 4200-374 Porto, Portugal"},{"name":"i3S\u2014Metabesity Research Team, Instituto de Investiga\u00e7\u00e3o e Inova\u00e7\u00e3o em Sa\u00fade, 4200-135 Porto, Portugal"},{"name":"FMUP\u2014Faculdade de Medicina, Universidade do Porto, 4200-319 Porto, Portugal"}]},{"given":"Marco","family":"Oliveira","sequence":"additional","affiliation":[{"name":"LABMI\u2014Laboratory of Medical and Industrial Biotechnology, 4200-374 Porto, Portugal"},{"name":"i3S\u2014Metabesity Research Team, Instituto de Investiga\u00e7\u00e3o e Inova\u00e7\u00e3o em Sa\u00fade, 4200-135 Porto, Portugal"},{"name":"ESB\u2014Escola Superior de Biotecnologia, Universidade Cat\u00f3lica Portuguesa, 4169-005 Porto, Portugal"}]},{"given":"Gustavo","family":"Accioly","sequence":"additional","affiliation":[{"name":"ESS\u2014Escola Superior de Sa\u00fade, IPP\u2014Porto Polytechnic Institute, 4200-072 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3740-862X","authenticated-orcid":false,"given":"Pilar","family":"Baylina","sequence":"additional","affiliation":[{"name":"LABMI\u2014Laboratory of Medical and Industrial Biotechnology, 4200-374 Porto, Portugal"},{"name":"ESS\u2014Escola Superior de Sa\u00fade, IPP\u2014Porto Polytechnic Institute, 4200-072 Porto, Portugal"},{"name":"i3S\u2014Metabesity Research Team, Instituto de Investiga\u00e7\u00e3o e Inova\u00e7\u00e3o em Sa\u00fade, 4200-135 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4537-5450","authenticated-orcid":false,"given":"Pedro","family":"Barata","sequence":"additional","affiliation":[{"name":"LABMI\u2014Laboratory of Medical and Industrial Biotechnology, 4200-374 Porto, Portugal"},{"name":"i3S\u2014Metabesity Research Team, Instituto de Investiga\u00e7\u00e3o e Inova\u00e7\u00e3o em Sa\u00fade, 4200-135 Porto, Portugal"},{"name":"UFP\u2014Faculdade de Ci\u00eancias da Sa\u00fade, Universidade Fernando Pessoa, 4200-253 Porto, Portugal"}]},{"given":"Cl\u00e1udia","family":"Pereira","sequence":"additional","affiliation":[{"name":"LABMI\u2014Laboratory of Medical and Industrial Biotechnology, 4200-374 Porto, Portugal"},{"name":"i3S\u2014Metabesity Research Team, Instituto de Investiga\u00e7\u00e3o e Inova\u00e7\u00e3o em Sa\u00fade, 4200-135 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8933-3984","authenticated-orcid":false,"given":"Ruben","family":"Fernandes","sequence":"additional","affiliation":[{"name":"LABMI\u2014Laboratory of Medical and Industrial Biotechnology, 4200-374 Porto, Portugal"},{"name":"ESS\u2014Escola Superior de Sa\u00fade, IPP\u2014Porto Polytechnic Institute, 4200-072 Porto, Portugal"},{"name":"i3S\u2014Metabesity 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