Bicarbonate stimulated adenylyl cyclases

Bicarbonate ion is fundamental to the biology of all living organisms. HCO3- is vital to such diverse physiological processes as carbon fixation, cellular homeostasis, sperm maturation, and nucleotide synthesis. A defined subset of adenylyl cyclases identified in eukaryotes and prokaryotes are directly activated by HCO3- . As such, cAMP represents the first identified biological effector for fluctuations in intracellular inorganic carbon levels. The identification of a signal transduction pathway activated by HCO3- has far reaching implications for understanding how the cell responds to fluctuations in this essential anion.