Dehydration effects on gelatin films of the D96N mutant bacteriorhodop
sin (BR) and wild-type BR were studied. Unlike the wild-type BR films,
wherein dehydration to 12% humidity results in an approximate 200-fol
d increase in the lifetime of the M state, D96N BR films dehydrated to
the same extent have been shown to exhibit only a 17- to 20-fold incr
ease in the lifetime of the M state. Chemically-enhanced D96N BR films
possess a total bleaching efficiency of the initial-to-M;state transi
tion that is close to theoretical maximum (1.0) over a wide range of r
elative humidity (35 to 85%). This provides an additional benefit to t
he D96N BR films as a material for storage and retrieval of optical in
formation.