Functional Coupling of Oxygen Binding and Vasoactivity inS-Nitrosohemoglobin
TJ McMahon, AE Stone, J Bonaventura… - Journal of Biological …, 2000 - jbc.org
S-Nitrosohemoglobin (SNO-Hb) is a vasodilator whose activity is allosterically modulated by
oxygen (" thermodyamic linkage"). Blood vessel contractions are favored in the oxygenated
structure, and vasorelaxant activity is" linked" to deoxygenation, as illustrated herein. We
further show that transnitrosation reactions between SNO-Hb and ambient thiols transduce
the NO-related bioactivity, whereas NO itself is inactive. One remaining problem is that the
amounts of SNO-Hb present in vivo are so large as to be incompatible with life were all theS …
oxygen (" thermodyamic linkage"). Blood vessel contractions are favored in the oxygenated
structure, and vasorelaxant activity is" linked" to deoxygenation, as illustrated herein. We
further show that transnitrosation reactions between SNO-Hb and ambient thiols transduce
the NO-related bioactivity, whereas NO itself is inactive. One remaining problem is that the
amounts of SNO-Hb present in vivo are so large as to be incompatible with life were all theS …