{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,2]],"date-time":"2026-01-02T06:32:50Z","timestamp":1767335570433,"version":"3.48.0"},"reference-count":131,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,1,2]],"date-time":"2026-01-02T00:00:00Z","timestamp":1767312000000},"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. Microbiol."],"abstract":"<jats:p>\n                    Hemes are iron-containing porphyrin compounds that play a crucial role in a wide array of biological processes. Heme\n                    <jats:italic>a<\/jats:italic>\n                    synthase (HAS) is a crucial enzyme that facilitates the biosynthesis of heme\n                    <jats:italic>a<\/jats:italic>\n                    , an essential heme variant that serves as a cofactor in heme-copper terminal oxidases and in some acidophilic archaea's quinol reductases, such as the\n                    <jats:italic>ba<\/jats:italic>\n                    complex. Depending on the length and presence or absence of cysteine residues in the periplasmic loop(s), HAS has been classified into different types. Our manuscript presents a large-scale analysis of the distribution and evolution of HAS in Archaea in comparison to Bacteria, revealing evolutionary patterns among the proposed subtypes, with types 1 and 2 diverging early. This study also underscores the complexity of HAS enzyme evolution, which reflects deep ancestral innovations as well as recent ecological pressures.\n                  <\/jats:p>","DOI":"10.3389\/fmicb.2025.1706049","type":"journal-article","created":{"date-parts":[[2026,1,2]],"date-time":"2026-01-02T06:28:07Z","timestamp":1767335287000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Archaeal heme a synthase: evolutionary trajectory distinct from bacterial homologs"],"prefix":"10.3389","volume":"16","author":[{"given":"Val","family":"Karavaeva","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marco","family":"Rampin","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jordi","family":"Zamarre\u00f1o Beas","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"L\u00edgia M.","family":"Saraiva","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Filipa L.","family":"Sousa","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2026,1,2]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"e78237","DOI":"10.1371\/journal.pone.0078237","article-title":"Architecture and gene repertoire of the flexible genome of the extreme acidophile Acidithiobacillus caldus","volume":"8","author":"Acu\u00f1a","year":"2013","journal-title":"PLoS ONE"},{"key":"B2","doi-asserted-by":"publisher","first-page":"297","DOI":"10.1111\/j.1432-1033.1990.tb19123.x","article-title":"Cytochrome aa3 from Sulfolobus acidocaldarius. 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