Initial investigations of C4a-(hydro)peroxyflavin intermediate formation by dibenzothiophene monooxygenase.
Dibenzothiophene monooxygenase is the initiating enzyme in the Rhodococcus 4S biodesulfurization pathway. A member of the Class D flavin monooxygenases, it uses FMN to activate molecular oxygen for oxygenation of the substrate, dibenzothiophene. Here, we have used stopped-flow spectrophotometry to show that DszC forms a peroxyflavin intermediate in the absence of substrate. Mutagenesis of Ser163 and His391 to Ala appears to decrease the binding affinity for reduced FMN and eliminates the enzyme's ability to stabilize the peroxyflavin intermediate.
Department of Chemistry and Biochemistry, California State University, Northridge, Northridge, CA 91330-8262, United States.
Liliana
L
Gonzalez-Osorio
Department of Chemistry and Biochemistry, California State University, Northridge, Northridge, CA 91330-8262, United States.
Kelvin
K
Luong
Department of Chemistry and Biochemistry, California State University, Northridge, Northridge, CA 91330-8262, United States.
Samatar
S
Jirde
Program in Chemical Biology, University of Michigan, Ann Arbor, MI 48109, United States; Department of Biological Chemistry, University of Michigan, Ann Arbor, MI 48109, United States.
Bruce A
BA
Palfey
Department of Chemistry and Biochemistry, California State University, Northridge, Northridge, CA 91330-8262, United States. Electronic address: jessica.vey@csun.edu.
Jessica L
JL
Vey
D002384:Catalysis; D004795:Enzyme Stability; D005415:Flavins / Q000138:chemical synthesis*; D006861:Hydrogen Peroxide / Q000737:chemistry*; D010088:Oxidoreductases / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry*; D011485:Protein Binding; D013329:Structure-Activity Relationship
C531259:C4a-hydroperoxyflavin; D005415:Flavins; D006861:Hydrogen Peroxide; D010088:Oxidoreductases; C090100:dibenzothiophene monooxygenase; D010100:Oxygen
Biodesulfurization; Dibenzothiophene; Flavin hydroperoxide; Flavin monooxygenase