Carnosine is a dipeptide composed of beta-alanine and histidine found exclusively in long-lived animal tissues. The cellular action of carnosine is still under extensive investigation; however, it has been proposed to have a role as an anti-oxidant and oxygen free radical scavenger, a physiological buffer, a heavy metal chelator, and has been implicated as an anti-aging agent.2,4 Our lab has been studying the interaction between carnosine and heme by analyzing both the effect carnosine has on the glycation of the heme containing protein cytochrome c and the interaction of carnosine with free hemin. We have observed that the addition of carnosine to glycated cytochrome c inhibits the formation of advanced glycation end product (AGE) structures. We have also found that the addition of carnosine to a solution of free hemin drastically increases the solubility of hemin and causes a shift of the max in its UV-Vis absorbance profile. We propose that carnosine is a natural intracellular heme chelator and that this interaction may act as a signal for cellular antioxidant processes. We have designed an experiment to identify proteins capable of binding to carnosine and heme-chelated carnosine. Using mass spectral techniques, we were able to identify a protein isolated from kidney tissue lysates using carnosine affinity beads. By identifying a carnosine protein binding partner, we gained a better understanding of the cellular action of carnosine that may eventually lead to the development of novel drugs for the treatment of a variety of diseases in which oxidative injury and cellular stress occurs
