title: Molecular characterization of a eukaryotic-like phenol hydroxylase from Corynebacterium glutamicum.
abstract: This study focuses on the genetic and biochemical characterization of phenol hydroxylase (Phe, NCgl2588) from Corynebacterium glutamicum that shares 31% identity in amino acids with phenol hydroxylase from yeast Trichosporon cutaneum but less similarity with that from bacteria. The phe deletion mutant significantly reduced its ability to grow with phenol as the sole carbon and energy source. Expression of the phe gene was strongly induced with phenol and also subject to the control of carbon catabolite repression (CCR). The molecular weight of purified Phe protein determined by gel filtration chromatography was 70 kDa, indicating that Phe exists as a monomer in the purification condition. However, Phe protein pre-incubated with phenol showed a molecular weight of 140 kDa, suggesting that Phe is likely active as a dimer. In addition to phenol, the Phe protein could utilize various other phenolic compounds as substrates. Site-directed mutagenesis revealed that D75, P261, R262, R269, C349 and C476 are key amino acid residues closely related to the enzyme activity of Phe.
authors.affiliation: State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University.
authors.forename: Xiao
authors.initials: X
authors.lastname: Xiao
authors.forename: Meiru
authors.initials: M
authors.lastname: Si
authors.forename: Zhifang
authors.initials: Z
authors.lastname: Yang
authors.forename: Yaoling
authors.initials: Y
authors.lastname: Zhang
authors.forename: Jingyuan
authors.initials: J
authors.lastname: Guan
authors.forename: Muhammad Tausif
authors.initials: MT
authors.lastname: Chaudhry
authors.forename: Yao
authors.initials: Y
authors.lastname: Wang
authors.forename: Xihui
authors.initials: X
authors.lastname: Shen
mesh_terms: D000595:Amino Acid Sequence; D057465:Catabolite Repression; D002850:Chromatography, Gel; D048230:Corynebacterium glutamicum / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D004926:Escherichia coli / Q000235:genetics; D007700:Kinetics; D006899:Mixed Function Oxygenases / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*; D008970:Molecular Weight; D016297:Mutagenesis, Site-Directed; D019800:Phenol / Q000378:metabolism; D010802:Phylogeny; D011994:Recombinant Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D017384:Sequence Deletion; D017386:Sequence Homology, Amino Acid; D013379:Substrate Specificity; D014250:Trichosporon / Q000201:enzymology
chemical_list: D011994:Recombinant Proteins; D019800:Phenol; D006899:Mixed Function Oxygenases; C022336:phenol 2-monooxygenase