Identification of an N-hydroxyguanidine reducing activity of xanthine oxidase.
Eur J Biochem
; 257(1): 178-84, 1998 Oct 01.
Article
in En
| MEDLINE
| ID: mdl-9799117
ABSTRACT
A guanoxabenz [1-(2,6-dichlorobenzylideneamino)-3-hydroxyguanidine; an N-hydroxyguanidine] reducing enzymatic activity of rat spleen cytosol was investigated. By means of protein purification and N-terminal amino acid sequencing, the reducing activity was shown to reside in xanthine oxidase. The action of the enzyme on guanoxabenz resulted in the formation of guanabenz [1-(2,6-dichlorobenzylidene-amino)-3-guanidine]; the product formation could be monitored by HPLC and its identity was confirmed by NMR analysis. The reduction of guanoxabenz required xanthine or NADH as reducing substrates, while the process could be blocked by allopurinol, a selective inhibitor of xanthine oxidase. By using bovine milk xanthine oxidase, the guanoxabenz reducing activity of the enzyme was also verified. We conclude that guanoxabenz is a novel electron acceptor structure for xanthine oxidase.
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Collection:
01-internacional
Database:
MEDLINE
Main subject:
Xanthine Oxidase
/
Guanidines
Type of study:
Diagnostic_studies
Limits:
Animals
Language:
En
Journal:
Eur J Biochem
Year:
1998
Document type:
Article
Affiliation country:
Suecia