Taming of a poison: biosynthesis of the NiFe-hydrogenase cyanide ligands.
NiFe-hydrogenases have an Ni-Fe site in which the iron has one CO and two CN groups as ligands. Synthesis of the CN ligands requires the activity of two hydrogenase maturation proteins: HypF and HypE. HypF is a carbamoyltransferase that transfers the carbamoyl moiety of carbamoyladenylate to the COOH-terminal cysteine of HypE and thus forms an enzyme-thiocarbamate. HypE dehydrates the S-carbamoyl moiety in an adenosine triphosphate-dependent process to yield the enzyme thiocyanate. Chemical model reactions corroborate the feasibility of this unprecedented biosynthetic route and show that thiocyanates can donate CN to iron. This finding underscores a striking parallel between biochemistry and organometallic chemistry in the formation of an iron-cyano complex.
Reissmann
Stefanie
S
Department Biologie I, Mikrobiologie, University of Munich, Maria-Ward-Strasse 1a, D-80638 Munich, Germany.
Hochleitner
Elisabeth
E
Wang
Haofan
H
Paschos
Athanasios
A
Lottspeich
Friedrich
F
Glass
Richard S
RS
Böck
August
A
D000249:Adenosine Monophosphate / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D020816:Amino Acid Motifs; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism*; D002221:Carbamyl Phosphate / Q000378:metabolism; D002248:Carbon Monoxide / Q000378:metabolism; D002384:Catalysis; D003486:Cyanides / Q000737:chemistry / Q000378:metabolism*; D003545:Cysteine / Q000737:chemistry / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000378:metabolism; D006864:Hydrogenase / Q000737:chemistry / Q000378:metabolism*; D007501:Iron / Q000737:chemistry / Q000378:metabolism*; D008024:Ligands; D013058:Mass Spectrometry; D008956:Models, Chemical; D010084:Oxidation-Reduction; D013861:Thiocyanates / Q000378:metabolism*
D001426:Bacterial Proteins; D003486:Cyanides; D029968:Escherichia coli Proteins; C108878:HypF protein, Bacteria; D008024:Ligands; D013861:Thiocyanates; C085871:hypE protein, Bacteria; D000249:Adenosine Monophosphate; D002221:Carbamyl Phosphate; D002248:Carbon Monoxide; D000255:Adenosine Triphosphate; C026976:thiocyanic acid; D007501:Iron; C043296:nickel-iron hydrogenase; D006864:Hydrogenase; D003545:Cysteine