title: Photoresponses of Halobacterium salinarum to repetitive pulse stimuli.
abstract: Halobacterium salinarum cells from 3-day-old cultures have been stimulated with different patterns of repetitive pulse stimuli. A short train of 0.6-s orange light pulses with a 4-s period resulted in reversal peaks of increasing intensity. The reverse occurred when blue light pulses were delivered as a finite train: with a 3-s period, the response declined in sequence from the first to the last pulse. To evaluate the response of the system under steady-state conditions of stimulation, continuous trains of pulses were also applied; whereas blue light always produced a sharply peaked response immediately after each pulse, orange pulses resulted in a declining peak of reversals that lasted until the subsequent pulse. An attempt to account for these results in terms of current excitation/adaptation models shows that additional mechanisms appear to be at work in this transduction chain.
authors.affiliation: Dipartimento di Fisiologia e Biochimica, Università di Pisa, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Cercignani
authors.forename: S
authors.initials: S
authors.lastname: Lucia
authors.forename: D
authors.initials: D
authors.lastname: Petracchi
mesh_terms: D055592:Biophysical Phenomena; D001703:Biophysics; D019617:Halobacterium salinarum / Q000502:physiology* / Q000528:radiation effects*; D008027:Light; D008954:Models, Biological; D009068:Movement / Q000502:physiology / Q000528:radiation effects; D010775:Photic Stimulation; D020283:Photoreceptors, Microbial / Q000502:physiology / Q000528:radiation effects; D015398:Signal Transduction
chemical_list: D020283:Photoreceptors, Microbial