Dependence of M, N and O states decay kinetics of D96N bacteriorhodopsin on amine and amino compounds and its application in chemical sensing

Abstract

Abstract The dependence of the kinetics of M, N and O states decay of the D96N bacteriorhodopsin (BR) on (i) ammonium ion and (ii) an aromatic amine is reported. The kinetics of decay back to trans BR at 410, 530 and 640 nm, which are the absorption maximum for M, N and O states, respectively, in presence and absence of these analytes are studies for better understanding of the kinetics of M state decay back to trans BR as reported earlier [P.C. Pandey et al. Sensors and Actuators, 35–36 (1996) 470–474]. The half time (T1/2) of these decays and absorption spectra are measured at 410, 530 and 640 nm, respectively. The half time(T1/2) of these decay at 410 nm increases in the presence of amine whereas it decreases in the presence of amino compounds as compared with control. Similar trends have been observed at 530 and 640 nm. The reverse is observed on the measurement of absorption. The variation of these parameters are more apparent when measurements are carried out at 530 nm. The application of the kinetic data in the construction of chemical sensors is discussed and the analysis of ammonium ion and amine is reported.