title: Degradation of 2-hydroxybiphenyl and 2,2'-dihydroxybiphenyl by Pseudomonas sp. strain HBP1.
abstract: Pseudomonas sp. strain HBP1 was found to grow on 2-hydroxy- and 2,2'-dihydroxy-biphenyl as the sole carbon and energy sources. The first step in the degradation of these compounds was catalyzed by an NADH-dependent monooxygenase. The enzyme inserted a hydroxyl group adjacent to the already existing hydroxyl group to form 2,3-dihydroxybiphenyl when acting on 2-hydroxybiphenyl and to form 2,2',3-trihydroxybiphenyl when acting on 2,2'-dihydroxybiphenyl. To be substrates of the monooxygenase, compounds required a 2-hydroxyphenyl-R structure, with R being a hydrophobic group (e.g., methyl, ethyl, propyl, sec-butyl, phenyl, or 2-hydroxyphenyl). Several chlorinated hydroxybiphenyls served as pseudosubstrates by effecting consumption of NADH and oxygen without being hydroxylated. Further degradation of 2,3-dihydroxy- and 2,2',3-trihydroxybiphenyl involved meta cleavage, with subsequent formation of benzoate and salicylate, respectively.
authors.affiliation: Department of Soil and Environmental Sciences, University of California, Riverside 92521.
authors.forename: H P
authors.initials: HP
authors.lastname: Kohler
authors.forename: D
authors.initials: D
authors.lastname: Kohler-Staub
authors.forename: D D
authors.initials: DD
authors.lastname: Focht
mesh_terms: D001673:Biodegradation, Environmental; D001713:Biphenyl Compounds / Q000378:metabolism*; D055598:Chemical Phenomena; D002621:Chemistry; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D006899:Mixed Function Oxygenases / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism; D010636:Phenols / Q000378:metabolism*; D011549:Pseudomonas / Q000201:enzymology / Q000254:growth & development / Q000378:metabolism*; D012722:Sewage; D013055:Spectrophotometry, Infrared; D013056:Spectrophotometry, Ultraviolet
chemical_list: D001713:Biphenyl Compounds; D010636:Phenols; D012722:Sewage; C004369:2-phenylphenol; D006899:Mixed Function Oxygenases; C058145:2-hydroxybiphenyl 3-monooxygenase; C038764:2,2'-biphenol; D010100:Oxygen