An S-nitrosothiol (SNO) synthase function of hemoglobin that utilizes nitrite as a substrate.

ABSTRACT: Red blood cells (RBCs) act as O(2)-responsive transducers of vasodilator and vasoconstrictor activity in lungs and tissues by regulating the availability of nitric oxide (NO). Vasodilation by RBCs is impaired in diseases characterized by hypoxemia. We have proposed that the extent to which RBCs constrict vs. dilate vessels is, at least partly, controlled by a partitioning between NO bound to heme iron and to Cysbeta93 thiol of hemoglobin (Hb). Hemes sequester NO, whereas thiols deploy NO bioactivity. In recent work, we have suggested that specific micropopulations of NO-liganded Hb could support the chemistry of S-nitrosohemoglobin (SNO-Hb) formation. Here, by using nitrite as the source of NO, we demonstrate that a (T state) micropopulation of a heme-NO species, with spectral and chemical

SUBMITTER: Angelo M 

PROVIDER: S-EPMC1482500 | biostudies-literature | 2006 May

REPOSITORIES: biostudies-literature