1 H‐NMR study of the interaction of aminopyrine with purified rat liver microsomal cytochrome P‐450

• Published in: FEBS letters Vol. 181; no. 2; pp. 295 - 299
• Main Authors: Woldman, Ya.Yu, Weiner, L.M., Gulyaeva, L.F., Lyakhovich, V.V.
• Format: Journal Article
• Language: English
• Published: 25-02-1985
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/0014-5793(85)80279-9

Longitudinal relaxation (
T
1
) measurements for all lines (N(CH
3
)
2
, N(CH
3
), (C(CH
3
), phenyl) in the aminopyrine
1
H‐NMR spectrum were used to study the interaction of aminopyrine with purified microsomal cytochrome P‐450 from livers of phenobarbital‐treated rats. The paramagnetic contribution to the observed
t
1
−1
values was determined from its dependence on aminopyrine concentration. The Solomon‐Bloembergen equation was used to calculate between Fe
3+
and aminopyrine distances in the enzyme‐substrate complex. For all protons these distances are about 8 Å.