Cysteine biosynthesis in the Archaea: Methanosarcina thermophila utilizes O-acetylserine sulfhydrylase.
Two pathways for cysteine biosynthesis are known in nature; however, it is not known which, if either, the Archaea utilize. Enzyme activities in extracts of Methanosarcina thermophila grown with combinations of cysteine and sulfide as sulfur sources indicated that this archaeon utilizes the pathway found in the Bacteria domain. The genes encoding serine transacetylase and O-acetylserine sulfhydrylase (cysE and cysK) are adjacent on the chromosome of M. thermophila and possibly form an operon. When M. thermophila is grown with cysteine as the sole sulfur source, O-acetylserine sulfhydrylase activity is maximally expressed suggesting alternative roles for this enzyme apart from cysteine biosynthesis.
Department of Chemistry, Pennsylvania State University, University Park, PA 16802, USA.
B
B
Borup
J G
JG
Ferry
D000595:Amino Acid Sequence; D019757:Carbon-Oxygen Lyases / Q000235:genetics / Q000378:metabolism*; D003545:Cysteine / Q000096:biosynthesis*; D003547:Cysteine Synthase; D017020:Methanosarcina / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D009097:Multienzyme Complexes; D029701:Saccharomyces cerevisiae Proteins; D016415:Sequence Alignment; D013455:Sulfur / Q000378:metabolism*
D009097:Multienzyme Complexes; D029701:Saccharomyces cerevisiae Proteins; D013455:Sulfur; D003547:Cysteine Synthase; C103381:MET17 protein, S cerevisiae; C018725:O-acetylhomoserine (thiol)-lyase; D019757:Carbon-Oxygen Lyases; D003545:Cysteine