title: Structure and Function of Benzylsuccinate Synthase and Related Fumarate-Adding Glycyl Radical Enzymes.
abstract: The pathway of anaerobic toluene degradation is initiated by a remarkable radical-type enantiospecific addition of the chemically inert methyl group to the double bond of a fumarate cosubstrate to yield (R)-benzylsuccinate as the first intermediate, as catalyzed by the glycyl radical enzyme benzylsuccinate synthase. In recent years, it has become clear that benzylsuccinate synthase is the prototype enzyme of a much larger family of fumarate-adding enzymes, which play important roles in the anaerobic metabolism of further aromatic and even aliphatic hydrocarbons. We present an overview on the biochemical properties of benzylsuccinate synthase, as well as its recently solved structure, and present the results of an initial structure-based modeling study on the reaction mechanism. Moreover, we compare the structure of benzylsuccinate synthase with those predicted for different clades of fumarate-adding enzymes, in particular the paralogous enzymes converting p-cresol, 2-methylnaphthalene or n-alkanes.
authors.affiliation: Laboratory of Microbial Biochemistry, LOEWE Center for Synthetic Microbiology, Philipps University Marburg, Marburg, Germany.
authors.forename: Johann
authors.initials: J
authors.lastname: Heider
authors.forename: Maciej
authors.initials: M
authors.lastname: Szaleniec
authors.forename: Berta M
authors.initials: BM
authors.lastname: Martins
authors.forename: Deniz
authors.initials: D
authors.lastname: Seyhan
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Buckel
authors.forename: Bernard T
authors.initials: BT
authors.lastname: Golding
mesh_terms: D000693:Anaerobiosis; D001421:Bacteria, Anaerobic / Q000201:enzymology / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000378:metabolism; D001673:Biodegradation, Environmental; D019755:Carbon-Carbon Lyases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D005650:Fumarates / Q000378:metabolism*; D007527:Isoenzymes; D053858:Metabolic Networks and Pathways; D008958:Models, Molecular; D010802:Phylogeny; D013329:Structure-Activity Relationship; D014050:Toluene / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D005650:Fumarates; D007527:Isoenzymes; D014050:Toluene; D019755:Carbon-Carbon Lyases; C114354:benzylsuccinate synthase