Kinetics of nitric oxide binding to R-state hemoglobin

被引：27

作者：

Huang, Z

Ucer, KB

Murphy, T

Williams, RT

King, SB

Kim-Shapiro, DB ^{[1
]}

机构：

[1] Wake Forest Univ, Dept Phys, Winston Salem, NC 27109 USA

[2] Wake Forest Univ, Dept Chem, Winston Salem, NC 27109 USA

来源：

BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS | 2002年 / 292卷 / 04期

关键词：

hemoglobin; nitric oxide; allostery; time-resolved absorption spectroscopy;

D O I：

10.1006/bbrc.2002.6730

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

Despite earlier work indicating otherwise, some recent reports have suggested that nitric oxide (NO) binds to hemoglobin cooperatively. In particular, it has been suggested that, under physiological conditions, NO binds to the high-affinity R-state hemoglobin as much as 100 times faster than to the low-affinity T-state hemoglobin. This rapid NO binding could provide a means of preserving NO bioactivity. However, using a flash-flow photolysis technique, we have determined that the rate of NO binding to normal adult R-state hemoglobin is (2.1 +/- 0.1) x 10(7) (s(-1) M-1 which is essentially the same as that reported for T-state NO binding. (C) 2002 Elsevier Science (USA).

引用

页码：812 / 818

页数：7

共 32 条

[1] Allosteric intermediates in hemoglobin .1. Nanosecond time-resolved circular dichroism spectroscopy [J].