title: Photoinduced kinetics of bacteriorhodopsin in a dried xerogel glass.
abstract: Time-resolved absorption measurements of the formation and decay kinetics of the M (deprotonated) photocycle intermediate of bR purple membranes entrapped within a dried xerogel glass have been investigated. The dramatic change observed for the M state decay time is in contrast to the relatively insensitive half life reported for the M intermediate of the D96N mutant entrapped within a dried sol-gel glass. The decay kinetics of the M intermediate was observed to slow by a factor of almost 100 when the solvent was removed from the wet-gel to form the dry xerogel glass. Very long aging times for wet-gels resulted in highly biexponential M state decay kinetics. Upon drying, the M state formation rate initially decreased relative to that in solution before increasing in the dry xerogel to a formation rate nearly three times faster than in solution.
authors.affiliation: Department of Chemistry, California State University, San Bernardino, CA 92407-2397, USA. lshamans@csusb.edu
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Shamansky
authors.forename: Kenny Minh
authors.initials: KM
authors.lastname: Luong
authors.forename: Duly
authors.initials: D
authors.lastname: Han
authors.forename: Eric L
authors.initials: EL
authors.lastname: Chronister
mesh_terms: D001436:Bacteriorhodopsins / Q000378:metabolism*; D005782:Gels; D007700:Kinetics; D008027:Light; D012996:Solutions; D013053:Spectrophotometry
chemical_list: D005782:Gels; D012996:Solutions; D001436:Bacteriorhodopsins