{"title":"自由基 SAM 环烷合成酶的序列-功能空间揭示了影响底物特异性的保守活性位点残基。","authors":"Chin-Soon Phan, Brandon I Morinaka","doi":"10.1039/d4cb00227j","DOIUrl":null,"url":null,"abstract":"<p><p>Radical SAM cyclophane synthases catalyze C-C, C-N, and C-O crosslinking reactions in the biosynthesis of bioactive peptide natural products. Here, we studied an uncharacterized rSAM enzyme, HtkB from <i>Pandoraea</i> sp., and found this enzyme to catalyze the formation of a HisC2-to-LysCβ crosslink. We used a combination of ColabFold and mutagenesis studies to show that residues D214 in HtkB and H204 in HaaB (another cyclophane synthase) are important for substrate specificity. Mutation of these residues changes the specificity and lowers substrate recognition on the wild-type motifs. This result opens opportunities to alter the specificity and promiscuity for rSAM peptide modifying enzymes.</p>","PeriodicalId":40691,"journal":{"name":"RSC Chemical Biology","volume":null,"pages":null},"PeriodicalIF":4.2000,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11499958/pdf/","citationCount":"0","resultStr":"{\"title\":\"Sequence-function space of radical SAM cyclophane synthases reveal conserved active site residues that influence substrate specificity.\",\"authors\":\"Chin-Soon Phan, Brandon I Morinaka\",\"doi\":\"10.1039/d4cb00227j\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>Radical SAM cyclophane synthases catalyze C-C, C-N, and C-O crosslinking reactions in the biosynthesis of bioactive peptide natural products. Here, we studied an uncharacterized rSAM enzyme, HtkB from <i>Pandoraea</i> sp., and found this enzyme to catalyze the formation of a HisC2-to-LysCβ crosslink. We used a combination of ColabFold and mutagenesis studies to show that residues D214 in HtkB and H204 in HaaB (another cyclophane synthase) are important for substrate specificity. Mutation of these residues changes the specificity and lowers substrate recognition on the wild-type motifs. This result opens opportunities to alter the specificity and promiscuity for rSAM peptide modifying enzymes.</p>\",\"PeriodicalId\":40691,\"journal\":{\"name\":\"RSC Chemical Biology\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":4.2000,\"publicationDate\":\"2024-10-23\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11499958/pdf/\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"RSC Chemical Biology\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1039/d4cb00227j\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"BIOCHEMISTRY & MOLECULAR BIOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"RSC Chemical Biology","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1039/d4cb00227j","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"BIOCHEMISTRY & MOLECULAR BIOLOGY","Score":null,"Total":0}
Sequence-function space of radical SAM cyclophane synthases reveal conserved active site residues that influence substrate specificity.
Radical SAM cyclophane synthases catalyze C-C, C-N, and C-O crosslinking reactions in the biosynthesis of bioactive peptide natural products. Here, we studied an uncharacterized rSAM enzyme, HtkB from Pandoraea sp., and found this enzyme to catalyze the formation of a HisC2-to-LysCβ crosslink. We used a combination of ColabFold and mutagenesis studies to show that residues D214 in HtkB and H204 in HaaB (another cyclophane synthase) are important for substrate specificity. Mutation of these residues changes the specificity and lowers substrate recognition on the wild-type motifs. This result opens opportunities to alter the specificity and promiscuity for rSAM peptide modifying enzymes.