The first messenger, Nitric Oxide: 
NO signals on land and in the oceans

Joseph Bonaventura, Ph.D.
Duke University Marine Laboratory

Wednesday, August 21, 2002
3:00 p.m.–Pacific Forum

Until a scant decade ago, nitric oxide was the culprit of atmospheric pollution and many other environmental insults. Everyone now knows that this all-important biological signaling molecule is responsible for processes ranging from blood pressure control to combating infections—in humans. But what about other organisms? What about NO in the oceans? Rich redox chemistry of NO gives this molecule functional flexibility that allows it to interact with both metal and non-metal components of biological molecules.  Many of the basic discoveries linking NO to biological systems have arisen from structure-function relationships in hemoglobin. Many other proteins involved in NO biology are heme proteins where NO coordination plays an essential function. In this regard, we may view hemoglobin as a microcosm of NO biology.

Invertebrates provide rich examples in which to explore alternate functions, or even perhaps the original functions, of the globins. Oxygen-carrying proteins could well have evolved from metalloproteins that primarily functioned in nitrogen metabolism rather than reversible oxygen binding. Newly discovered aspects of Hb function relate to the signaling and control processes that nitric oxide shows in biological systems.