{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,11]],"date-time":"2026-02-11T19:18:15Z","timestamp":1770837495931,"version":"3.50.1"},"reference-count":38,"publisher":"Public Library of Science (PLoS)","issue":"2","license":[{"start":{"date-parts":[[2026,2,11]],"date-time":"2026-02-11T00:00:00Z","timestamp":1770768000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000057","name":"National Institute of General Medical Sciences","doi-asserted-by":"publisher","award":["GM 52049"],"award-info":[{"award-number":["GM 52049"]}],"id":[{"id":"10.13039\/100000057","id-type":"DOI","asserted-by":"publisher"}]},{"name":"UMBC Designated Research Initiative Fund"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:p>\n                    The single-stranded DNA binding protein of bacteriophage T4, gp32, has important roles in replication, recombination, and repair. gp32 possesses three domains: the central (core) domain which contains the binding trough for single-stranded DNA, the N-terminal domain, which interacts with the core domain of an adjacent ssDNA-bound protein, bringing about binding cooperativity, and the C-terminal domain, which interacts with other proteins involved in replication, recombination, and repair. The essential residues within the N-domain for the association with the adjacent DNA bound gp32, Lys-Arg-Lys-Ser-Thr, the\n                    <jats:italic>\u201cLAST Motif\u201d<\/jats:italic>\n                    , is almost identical to the ssDNA-interactive residues within the core domain binding trough, and was the basis of a model in which a \u201cclosed\u201d \u21c4 \u201copen\u201d conformational change within core domain controls DNA binding. In this study, we show that alteration of the core domain\n                    <jats:italic>LAST sequence<\/jats:italic>\n                    , while maintaining its\n                    <jats:italic>composition<\/jats:italic>\n                    , can have an effect on the binding parameters, and may be the result of a shift in the closed-open equilibrium. Additionally, utilizing a gp32 truncated at residue 227, as well as amino acid substituted variants, we have further localized the residues within the core domain responsible for the protein-protein association leading to cooperative ssDNA binding. Truncation leads to an increase in the non-cooperative affinity for single-stranded nucleic acids, which can be explained by the absence of a closed conformation in this variant. The truncated protein forms a tight complex with core domain on a 12-residue oligonucleotide, a potential candidate for further structural study.\n                  <\/jats:p>","DOI":"10.1371\/journal.pone.0332487","type":"journal-article","created":{"date-parts":[[2026,2,11]],"date-time":"2026-02-11T18:34:43Z","timestamp":1770834883000},"page":"e0332487","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Bacteriophage T4 gene 32 protein: Insights into its interaction with ssDNA, binding cooperativity, and conformational change"],"prefix":"10.1371","volume":"21","author":[{"given":"Jules","family":"Guei","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Michael P.","family":"Chapman","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Paul N.","family":"Brothers","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shital","family":"Desai","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1891-644X","authenticated-orcid":true,"given":"Richard L.","family":"Karpel","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"340","published-online":{"date-parts":[[2026,2,11]]},"reference":[{"issue":"3","key":"pone.0332487.ref001","first-page":"1154","article-title":"Function of gene 32-protein, a new protein essential for the genetic recombination and replication of T4 bacteriophage DNA","volume":"29","author":"BM Alberts","year":"1970","journal-title":"Fed Proc"},{"issue":"5265","key":"pone.0332487.ref002","doi-asserted-by":"crossref","first-page":"1313","DOI":"10.1038\/2271313a0","article-title":"T4 bacteriophage gene 32: a structural protein in the replication and recombination of DNA","volume":"227","author":"BM Alberts","year":"1970","journal-title":"Nature"},{"key":"pone.0332487.ref003","first-page":"103","article-title":"T4 Bacteriophage Gene 32 Protein.","volume-title":"The Biology of Non-Specific DNA-Protein Interactions","author":"RL Karpel","year":"1990"},{"issue":"3","key":"pone.0332487.ref004","doi-asserted-by":"crossref","first-page":"161","DOI":"10.1080\/15216540212332","article-title":"LAST motifs and SMART domains in gene 32 protein: an unfolding story of autoregulation?","volume":"53","author":"RL Karpel","year":"2002","journal-title":"IUBMB Life"},{"issue":"8","key":"pone.0332487.ref005","doi-asserted-by":"crossref","first-page":"718","DOI":"10.2174\/1389203716666150505231019","article-title":"DNA Binding Proteins and Drug Delivery Vehicles: Tales of Elephants and Snakes","volume":"16","author":"RL Karpel","year":"2015","journal-title":"Curr Protein Pept Sci"},{"issue":"4","key":"pone.0332487.ref006","doi-asserted-by":"crossref","first-page":"165","DOI":"10.1016\/S0968-0004(00)01559-0","article-title":"Recombination-dependent DNA replication in phage T4","volume":"25","author":"KN Kreuzer","year":"2000","journal-title":"Trends Biochem Sci"},{"key":"pone.0332487.ref007","first-page":"231","article-title":"Prokaryotic DNA-binding Proteins. 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