RANDOM HETEROPOLYMER ADSORPTION ON DISORDERED MULTIFUNCTIONAL SURFACES - EFFECT OF SPECIFIC INTERSEGMENT INTERACTIONS

Biopolymers adsorb on cell and virus surfaces with great specificity. Recently, theoretical and computational studies have inquired as to wh ether there are any universal design strategies that nature employs in order to affect such recognition. Specifically, the efficacy of multi functionality and quenched disorder as essential design strategies has been explored. It has been found that when random heteropolymers inte ract with disordered multifunctional surfaces,a sharp transition from weak to strong adsorption occurs when the statistics characterizing th e sequence and surface site distributions are related in a special way . The aforementioned studies consider the intersegment interactions to be much weaker than the surface site interactions. In this work we us e nondynamic ensemble growth Monte Carlo simulations to study the effe ct of the competition between frustrating intersegment and segment-sur face interactions. We find that as the intersegment interactions becom e stronger, the transition from weak to strong adsorption occurs at hi gher surface disorder strengths. This trend is reversed beyond a thres hold strength of the intersegment interactions because interactions wi th the surface are no longer able to ''unravel'' the dominant conforma tions favored by the intersegment interactions. (C) 1998 American Inst itute of Physics. [S0021-9606(98)70639-7].