biostudies-literatureTallant CEuropean Commission FP713951-7https://www.ebi.ac.uk/biostudies/studies/S-EPMC2859557biostudies-literatureUnknown285(18)The metzincins are a clan of metallopeptidases consisting of families that share a series of structural elements. Among them is the Met-turn, a tight 1,4-turn found directly below the zinc-binding site, which is structurally and spatially conserved and invariantly shows a methionine at position 3 in all metzincins identified. The reason for this conservation has been a matter of debate since its discovery. We have studied this structural element in Methanosarcina acetivorans ulilysin, the structural prototype of the pappalysin family, by generating 10 mutants that replaced methionine with proteogenic amino acids. We compared recombinant overexpression yields, autolytic and tryptic activation, proteolytic activity, thermal stability, and three-dimensional structure with those of the wild tyThe Journal of biological chemistryOn the relevance of the Met-turn methionine in metzincins.PMC2859557FP7_223101Tallant CBaumann UGomis-Ruth FXGarcia-Castellanos RfalseOn the relevance of the Met-turn methionine in metzincins.The metzincins are a clan of metallopeptidases consisting of families that share a series of structural elements. Among them is the Met-turn, a tight 1,4-turn found directly below the zinc-binding site, which is structurally and spatially conserved and invariantly shows a methionine at position 3 in all metzincins identified. The reason for this conservation has been a matter of debate since its discovery. We have studied this structural element in Methanosarcina acetivorans ulilysin, the structural prototype of the pappalysin family, by generating 10 mutants that replaced methionine with proteogenic amino acids. We compared recombinant overexpression yields, autolytic and tryptic activation, proteolytic activity, thermal stability, and three-dimensional structure with those of the wild ty2010-01-01T00:00:00Z2010 Apr2026-05-04T11:23:26.279Z2019-03-27T00:30:21ZS-EPMC28595572020293710.1074/jbc.M109.08337810.1074/jbc.m109.083378