Benzoic acid 2-hydroxylase, a soluble oxygenase from tobacco, catalyzes salicylic acid biosynthesis
- Rutgers Univ., New Brunswick, NJ (United States); and others
Benzoic acid 2-hydroxylase (BA2H) catalyzes the biosynthesis of salicylic acid from benzoic acid. The enzyme has been partially purified and characterized as a soluble protein of 160 kDa. High-efficiency in vivo labeling of salicyclic acid with {sup 18}O{sub 2} suggested that BA2H is an oxygenase that specifically hydroxylates the ortho position of benzoic acid. The enzyme was strongly induced by either tobacco mosaic virus inoculation of benzoic acid infiltration of tobacco leaves and it was inhibited by CO and other inhibitors of cytochrome P450 hydroxylases. The BA2H activity was immunodepleted by antibodies raised against SU2, a soluble cytochrome P450 from Streptomyces griseolus. The anti-SU2 antibodies immunoprecipitated a radiolabeled polypeptide of around 160 kDa from the soluble protein extracts of L-[{sup 35}S]-methionine-fed tobacco leaves. Purified BA2H showed CO-difference spectra with a maximum at 457 nm. These data suggest that BA2H belongs to a novel class of soluble, high molecular weight cytochrome P450 enzymes. 21 refs., 6 figs., 1 tab.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 183562
- Journal Information:
- Proceedings of the National Academy of Sciences of the United States of America, Vol. 92, Issue 22; Other Information: PBD: 24 Oct 1995
- Country of Publication:
- United States
- Language:
- English
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