{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T08:49:13Z","timestamp":1791449353946,"version":"4.3.3"},"reference-count":35,"publisher":"Portland Press Ltd.","issue":"11","license":[{"start":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T00:00:00Z","timestamp":1790035200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/2.0\/"}],"funder":[{"DOI":"10.13039\/501100001502","name":"Department of Atomic Energy, Government of India","doi-asserted-by":"publisher","award":["N\/A"],"award-info":[{"award-number":["N\/A"]}],"id":[{"id":"10.13039\/501100001502","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["portlandpress.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2026,11,4]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>The cysteine-mediated catalytic reactions are essential for redox homeostasis in photosynthetic organisms. In the genome of cyanobacterium Anabaena PCC 7120 (Anabaena), the genes encoding thioredoxin reductase (TR; alr2204) and the atypical thioredoxin (Trx; alr2205) are contiguously located, but whether these proteins function as a redox pair remains unknown. Interestingly, Alr2204 and Alr2205, respectively, show high homology to the TR and Trx domains of the chloroplast NADPH-thioredoxin reductase C (NTRC). To delve into its possible role, Alr2204 was overexpressed in Anabaena. The resulting strain displayed elevated TR activity and demonstrated enhanced resistance to oxidative stresses. Biochemical characterization showed Alr2204 to be a FAD-associated, predominantly alpha helical protein with NADPH-dependent TR activity. Notably, Alr2204 supported the function of Trx Alr2205, indicating that Alr2204\u2013Alr2205 formed a cognate redox pair wherein Alr2204 donated electrons to Alr2205. When co-expressed in Anabaena, Alr2204 copurified with Alr2205, and together these proteins enhanced the cellular levels of the reduced form of 2-Cys-Prx, a physiologically vital antioxidant protein. Importantly, Alr2204\u2013Alr2205 also sustained peroxidase activity of 2-Cys-Prx. This is the first study to show that Alr2204\u2013Alr2205, though independently synthesized, are functionally analogous to the NTRC protein, and Trx systems can be modulated to enhance stress resistance in organisms.<\/jats:p>","DOI":"10.1042\/bcj20260355","type":"journal-article","created":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T13:32:00Z","timestamp":1790083920000},"page":"2075-2089","update-policy":"https:\/\/doi.org\/10.1042\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Alr2204\u2013Alr2205 form a functional modular thioredoxin system that enhances oxidative stress tolerance in cyanobacteria"],"prefix":"10.1042","volume":"483","author":[{"given":"Namrata","family":"Waghamare","sequence":"first","affiliation":[{"name":"1Molecular Biology Division, Bhabha Atomic Research Centre, Anushakti Nagar, Mumbai 400085, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Deepak\u00a0T.","family":"Hurali","sequence":"additional","affiliation":[{"name":"1Molecular Biology Division, Bhabha Atomic Research Centre, Anushakti Nagar, Mumbai 400085, India"},{"name":"2Homi Bhabha National Institute, Anushakti Nagar, Mumbai 400094 India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ragavendra\u00a0S.","family":"Patwardhan","sequence":"additional","affiliation":[{"name":"2Homi Bhabha National Institute, Anushakti Nagar, Mumbai 400094 India"},{"name":"3Radiation Biology and Health Science Division, Bhabha Atomic Research Centre, Anushakti Nagar, Mumbai 400085, India"},{"name":"4Radiobiology & Omics Lab, Radiological Research Unit, Bhabha Atomic Research Centre Facility, Kharghar, Navi Mumbai 410210, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3605-7741","authenticated-orcid":false,"given":"Manisha","family":"Banerjee","sequence":"additional","affiliation":[{"name":"1Molecular Biology Division, Bhabha Atomic Research Centre, Anushakti Nagar, Mumbai 400085, India"},{"name":"2Homi Bhabha National Institute, Anushakti Nagar, Mumbai 400094 India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8776-3021","authenticated-orcid":false,"given":"Anand","family":"Ballal","sequence":"additional","affiliation":[{"name":"2Homi Bhabha National Institute, Anushakti Nagar, Mumbai 400094 India"},{"name":"5Nuclear Agriculture & Biotechnology Division, Bhabha Atomic Research Centre, Anushakti Nagar, Mumbai 400085, India"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"288","published-online":{"date-parts":[[2026,10,8]]},"reference":[{"key":"2026100803511866600_B1","doi-asserted-by":"publisher","first-page":"642","DOI":"10.1111\/tpj.15856","article-title":"ROS production and signalling in chloroplasts: cornerstones and evolving concepts","volume":"111","author":"Foyer","year":"2022","journal-title":"Plant J."},{"key":"2026100803511866600_B2","doi-asserted-by":"publisher","first-page":"59","DOI":"10.1007\/s11120-013-9929-8","article-title":"Oxidative stress management in the filamentous, heterocystous, diazotrophic cyanobacterium, Anabaena PCC7120","volume":"118","author":"Banerjee","year":"2013","journal-title":"Photosynth. 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