biostudies-literatureWang SAHHS | NIH | National Institute of General Medical SciencesWelch FoundationNIH HHSNIGMS NIH HHS24794-24801https://www.ebi.ac.uk/biostudies/studies/S-EPMC7547251biostudies-literatureUnknown117(40)The structure of lincomycin A consists of the unusual eight-carbon thiosugar core methyllincosamide (MTL) decorated with a pendent <i>N</i>-methylprolinyl moiety. Previous studies on MTL biosynthesis have suggested GDP-ᴅ-<i>erythro</i>-α-ᴅ-<i>gluco</i>-octose and GDP-ᴅ-α-ᴅ-lincosamide as key intermediates in the pathway. However, the enzyme-catalyzed reactions resulting in the conversion of GDP-ᴅ-<i>erythro</i>-α-ᴅ-<i>gluco</i>-octose to GDP-ᴅ-α-ᴅ-lincosamide have not yet been elucidated. Herein, a biosynthetic subpathway involving the activities of four enzymes-LmbM, LmbL, CcbZ, and CcbS (the LmbZ and LmbS equivalents in the closely related celesticetin pathway)-is reported. These enzymes catalyze the previously unknown biosynthetic steps including 6-epimerization, 6,8-dehydration, 4-epimProceedings of the National Academy of Sciences of the United States of AmericaStudies of lincosamide formation complete the biosynthetic pathway for lincomycin A.PMC7547251GM035906R37 GM035906S10 OD021508R01 GM035906F-1511Zhang JWang SALiu HWSasaki EUshimaru RLin CIfalseStudies of lincosamide formation complete the biosynthetic pathway for lincomycin A.The structure of lincomycin A consists of the unusual eight-carbon thiosugar core methyllincosamide (MTL) decorated with a pendent <i>N</i>-methylprolinyl moiety. Previous studies on MTL biosynthesis have suggested GDP-ᴅ-<i>erythro</i>-α-ᴅ-<i>gluco</i>-octose and GDP-ᴅ-α-ᴅ-lincosamide as key intermediates in the pathway. However, the enzyme-catalyzed reactions resulting in the conversion of GDP-ᴅ-<i>erythro</i>-α-ᴅ-<i>gluco</i>-octose to GDP-ᴅ-α-ᴅ-lincosamide have not yet been elucidated. Herein, a biosynthetic subpathway involving the activities of four enzymes-LmbM, LmbL, CcbZ, and CcbS (the LmbZ and LmbS equivalents in the closely related celesticetin pathway)-is reported. These enzymes catalyze the previously unknown biosynthetic steps including 6-epimerization, 6,8-dehydration, 4-epim2020-01-01T00:00:00Z2020 Oct2025-04-18T13:42:04.582Z2025-04-06T23:28:07.066ZS-EPMC75472513295863910.1073/pnas.2009306117