creators_name: Sen, Himanshu creators_name: Choudhury, Gourab Basu creators_name: Das, Joyasree creators_name: Surin, Shradha creators_name: Ekka, Manjula creators_name: Saha, Angira creators_name: Saha, Debayan creators_name: Krishnamurthi, Srinivasan creators_name: Datta, Saumen creators_name: Raychaudhuri, Saumya type: article datestamp: 2026-07-14 04:43:09 lastmod: 2026-07-14 04:43:09 metadata_visibility: show title: Comprehensive findings of functional modulations linked to structural intricacies in DNA binding for HapR/LuxR homologues from the Vibrionaceae family ispublished: pub subjects: QR keywords: HapR/LuxR; Quorum sensing; Crystal structure; Vibrionaceae; Transcriptional regulators note: copyright of this Article belongs to ELSEVIER abstract: LuxR/HapR homologues play important roles in the regulation of virulence and protease genes in pathogenic Vibrio species like V. cholerae, V. vulnificus, V. parahaemolyticus, etc. as well as providing physiological advantages such as resistance to protozoan grazing, motility and chitin-induced competence in the aqueous environments. They are commonly termed as the high cell density master regulators. They are highly conserved in sequence and structure among the Vibrios and can recognize and bind to common DNA promoters, like activation of protease production in V. cholerae by SmcR of V. vulnificus. Despite this conservation, critical differences occur due to amino acid divergence in their sequences. In the present study, we compare the degree of functional conservation among HapR/LuxR homologues selected from various clades of the Vibrionaceae family, using a hapR mutant V. cholerae strain as a model organism. We also delve into the structural intricacies of distant HapR/LuxR homologues, such as LuxR proteins of Photobacterium spp. and HapR of Vibrio mimicus, a close homologue of V. cholerae. Evolutionary implications arising from sequence divergence are also recorded in the structural changes through the crystal structure analysis. The study compared several structural constraints responsible for the variation in functions related to transcriptional regulation. date: 2026-03-05 date_type: published publication: INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES volume: 348 publisher: ELSEVIER place_of_pub: RADARWEG 29, 1043 NX AMSTERDAM, NETHERLANDS refereed: TRUE official_url: https://www.sciencedirect.com/science/article/pii/S0141813026006483?via%3Dihub citation: Sen, Himanshu and Choudhury, Gourab Basu and Das, Joyasree and Surin, Shradha and Ekka, Manjula and Saha, Angira and Saha, Debayan and Krishnamurthi, Srinivasan and Datta, Saumen and Raychaudhuri, Saumya (2026) Comprehensive findings of functional modulations linked to structural intricacies in DNA binding for HapR/LuxR homologues from the Vibrionaceae family. INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES, 348. document_url: http://crdd.osdd.net/open/3463/1/references.bib