Kim, BR Kim, DH 2024-01-21T17:33:45Z 2024-01-21T17:33:45Z 2021-09-04 1998-01-06 0006-291X https://pubs.kist.re.kr/handle/201004/143293 The role of NADPH reductase and cytochrome b(5) on glutathione (GSH)-induced stimulation of P450 3A4 activity was investigated, GSH increased the V-max of testosterone GP-hydroxylation without changing the K-m for testosterone whereas it decreased the K-m for NADPH-P450 reductase, Addition of cytochrome b(5) inhibited testosterone 6 beta-hydroxylation in the reconstituted system, depleting GSH, while it dramatically enhanced the rate of testosterone 6 beta-hydroxylation in the presence of GSH, Cumene hydroperoxide-mediated P450 3A4 activity, which is independent of NADPH-P450 reductase and cytochrome b(5), was not affected by GSH. High concentration of GSH above 4 mM was inhibitory in the reconstituted systems, These results suggest that GSH increases the apparent affinity between P450 3A4 and NADPH-P450 reductase, and between P450 3A4 and cytochrome b(5), but has no effect on the affinity between P450 3A4 and testosterone. (C) 1998 Academic Press. English ACADEMIC PRESS INC NADPH-P450 REDUCTASE ESCHERICHIA-COLI FUSION PROTEIN LIVER TESTOSTERONE PURIFICATION AGGREGATION ACTIVATION OXIDATION MECHANISM Influence of glutathione on the catalytic activity of reconstituted cytochrome P450 3A4 Article 10.1006/bbrc.1997.7861 1 BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, v.242, no.1, pp.209 - 212 BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS 242 1 209 212 scie scopus 000071550600038 2-s2.0-0032488540 Biochemistry & Molecular Biology Biophysics Biochemistry & Molecular Biology Biophysics Article NADPH-P450 REDUCTASE ESCHERICHIA-COLI FUSION PROTEIN LIVER TESTOSTERONE PURIFICATION AGGREGATION ACTIVATION OXIDATION MECHANISM cytochrome P450 3A4