{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,7]],"date-time":"2026-05-07T12:21:48Z","timestamp":1778156508162,"version":"3.51.4"},"reference-count":52,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2025,10,29]],"date-time":"2025-10-29T00:00:00Z","timestamp":1761696000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>This review summarizes the current knowledge on the role of alternative \u03c3 factors in the highly invasive spirochaete Leptospira interrogans, the causative agent of leptospirosis. This globally distributed zoonosis affects both animals and humans, resulting in substantial public health and economic consequences. Together with the primary \u03c370, alternative \u03c3 factors provide transcriptional flexibility essential for bacterial adaptation to environmental changes and host\u2013pathogen interactions. Comparative genomic analyses have revealed that the L. interrogans genome encodes 14 \u03c3 factors, including one housekeeping \u03c370-like factor and three types of alternative \u03c3 factors: \u03c354, \u03c328, and 11 predicted extracytoplasmic function (ECF, \u03c3\u1d31-type) factors. This review discusses the characteristics of these regulators, with particular emphasis on the poorly understood ECF \u03c3 factors and their potential roles in gene regulation, adaptive responses, and pathogenicity.<\/jats:p>","DOI":"10.3390\/pathogens14111100","type":"journal-article","created":{"date-parts":[[2025,10,29]],"date-time":"2025-10-29T17:38:22Z","timestamp":1761759502000},"page":"1100","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Alternative Sigma Factors of RNA Polymerase as Master Regulators in the Pathogenic Spirochaete Leptospira interrogans"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5756-3013","authenticated-orcid":false,"given":"Sabina","family":"K\u0119dzierska-Mieszkowska","sequence":"first","affiliation":[{"name":"Department of General and Medical Biochemistry, Faculty of Biology, University of Gdansk, 80-308 Gdansk, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5997-2555","authenticated-orcid":false,"given":"Zbigniew","family":"Arent","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases and Public Health, Faculty of Veterinary Medicine, University of Agriculture in Krakow, 30-248 Krakow, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"287","DOI":"10.1016\/j.vetmic.2009.03.012","article-title":"Leptospira and leptospirosis","volume":"140","author":"Adler","year":"2010","journal-title":"Vet. 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