title: Structural Analysis of CYP101C1 from Novosphingobium aromaticivorans DSM12444.
abstract: CYP101C1 from Novosphingobium aromaticivorans DSM12444 is a homologue of CYP101D1 and CYP101D2 enzymes from the same bacterium and CYP101A1 from Pseudomonas putida. CYP101C1 does not bind camphor but is capable of binding and hydroxylating ionone derivatives including α- and β-ionone and β-damascone. The activity of CYP101C1 was highest with β-damascone (k(cat)=86 s(-1)) but α-ionone oxidation was the most regioselective (98 % at C3). The crystal structures of hexane-2,5-diol- and β-ionone-bound CYP101C1 have been solved; both have open conformations and the hexanediol-bound form has a clear access channel from the heme to the bulk solvent. The entrance of this channel is blocked when β-ionone binds to the enzyme. The heme moiety of CYP101C1 is in a significantly different environment compared to the other structurally characterised CYP101 enzymes. The likely ferredoxin binding site on the proximal face of CYP101C1 has a different topology but a similar overall positive charge compared to CYP101D1 and CYP101D2, all of which accept electrons from the ArR/Arx class I electron transfer system.
authors.affiliation: National Laboratory of Macromolecules, Institute of Biophysics, Chinese Academy of Science, Beijing 100101, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Ma
authors.forename: Stephen G
authors.initials: SG
authors.lastname: Bell
authors.forename: Wen
authors.initials: W
authors.lastname: Yang
authors.forename: Yiming
authors.initials: Y
authors.lastname: Hao
authors.forename: Nicholas H
authors.initials: NH
authors.lastname: Rees
authors.forename: Mark
authors.initials: M
authors.lastname: Bartlam
authors.forename: Weihong
authors.initials: W
authors.lastname: Zhou
authors.forename: Luet-Lok
authors.initials: LL
authors.lastname: Wong
authors.forename: Zihe
authors.initials: Z
authors.lastname: Rao
mesh_terms: D019475:Camphor 5-Monooxygenase / Q000737:chemistry* / Q000378:metabolism; D020134:Catalytic Domain; D006418:Heme / Q000737:chemistry / Q000378:metabolism; D007700:Kinetics; D008958:Models, Molecular; D045792:Norisoprenoids / Q000378:metabolism; D042301:Sphingomonadaceae / Q000201:enzymology*; D013379:Substrate Specificity
chemical_list: D045792:Norisoprenoids; D006418:Heme; C008157:beta-ionone; D019475:Camphor 5-Monooxygenase