title: The dehydratase activity of lacticin 481 synthetase is highly processive.
abstract: Lacticin 481 synthetase (LctM) is a bifunctional enzyme that undertakes dehydration and cyclization in the structural region of the pre-lacticin peptide (LctA) to introduce three thioether rings and one dehydrobutyrine residue. The order and timing of these events has been investigated employing high-resolution ESI-FTMS-based tandem MS/MS techniques and chemical derivatization. LctM demonstrates highly processive behavior as seen by MS analysis of the reaction course of dehydration. Furthermore, cyclization is not tightly coupled to dehydration and follows at a later stage of the enzymatic reaction.
authors.affiliation: Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
authors.forename: Leah M
authors.initials: LM
authors.lastname: Miller
authors.forename: Champak
authors.initials: C
authors.lastname: Chatterjee
authors.forename: Wilfred A
authors.initials: WA
authors.lastname: van der Donk
authors.forename: Neil L
authors.initials: NL
authors.lastname: Kelleher
mesh_terms: D000595:Amino Acid Sequence; D001430:Bacteriocins / Q000737:chemistry / Q000378:metabolism*; D003500:Cyclization; D004798:Enzymes / Q000737:chemistry / Q000378:metabolism*; D006836:Hydro-Lyases / Q000737:chemistry / Q000378:metabolism*; D008969:Molecular Sequence Data; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D001430:Bacteriocins; D004798:Enzymes; C481644:LctM protein, Lactococcus lactis; C082508:lacticin 481; D006836:Hydro-Lyases