Pumped biochemical reactions, nonequilibrium circulation, and stochastic resonance

Based on a master equation formalism for mesoscopic, unimolecular biochemic al reactions, we show the periodic oscillation arising from severe nonequil ibrium pumping is intimately related to the periodic motion in recently stu died stochastic resonance (SR). The white noise in SR is naturally identifi ed with the temperature in the biochemical reactions; the drift in the SR i s associated with the circular flux in nonequilibrium steady state (NESS). As in SR, an optimal temperature for biochemical oscillation is shown to ex ist. A unifying framework for Hill's theory of NESS and the SR without peri odic forcing is presented. The new formalism provides an analytically solva ble model for SR.