title: Post-translational modifications in the active site region of methyl-coenzyme M reductase from methanogenic and methanotrophic archaea.
abstract: Methyl-coenzyme M reductase (MCR) catalyzes the methane-forming step in methanogenic archaea. Isoenzyme I from Methanothermobacter marburgensiswas shown to contain a thioxo peptide bond and four methylated amino acids in the active site region. We report here that MCRs from all methanogens investigated contain the thioxo peptide bond, but that the enzymes differ in their post-translational methylations. The MS analysis included MCR I and MCR II from Methanothermobacter marburgensis, MCR I from Methanocaldococcus jannaschii and Methanoculleus thermophilus, and MCR from Methanococcus voltae, Methanopyrus kandleri and Methanosarcina barkeri. Two MCRs isolated from Black Sea mats containing mainly methanotrophic archaea of the ANME-1 cluster were also analyzed.
authors.affiliation: Max Planck Institute for Terrestrial Microbiology, Marburg, Germany.
authors.forename: Jörg
authors.initials: J
authors.lastname: Kahnt
authors.forename: Bärbel
authors.initials: B
authors.lastname: Buchenau
authors.forename: Felix
authors.initials: F
authors.lastname: Mahlert
authors.forename: Martin
authors.initials: M
authors.lastname: Krüger
authors.forename: Seigo
authors.initials: S
authors.lastname: Shima
authors.forename: Rudolf K
authors.initials: RK
authors.lastname: Thauer
mesh_terms: D000595:Amino Acid Sequence; D001105:Archaea / Q000201:enzymology* / Q000378:metabolism*; D001120:Arginine / Q000031:analogs & derivatives / Q000378:metabolism; D001665:Binding Sites; D003545:Cysteine / Q000031:analogs & derivatives / Q000378:metabolism; D005973:Glutamine / Q000031:analogs & derivatives / Q000378:metabolism; D005998:Glycine / Q000031:analogs & derivatives / Q000378:metabolism; D006639:Histidine / Q000031:analogs & derivatives / Q000378:metabolism; D008697:Methane / Q000378:metabolism*; D008969:Molecular Sequence Data; D010088:Oxidoreductases / Q000737:chemistry* / Q000378:metabolism*; D011499:Protein Processing, Post-Translational; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014357:Trypsin / Q000378:metabolism
chemical_list: D005973:Glutamine; D006639:Histidine; D001120:Arginine; C008425:S-methylcysteine; D010088:Oxidoreductases; C021572:methyl coenzyme M reductase; D014357:Trypsin; D003545:Cysteine; D008697:Methane; D005998:Glycine