Bleaching of bacteriorhodopsin by continuous light.

Z Dancsházy; Z Tokaji; A Dér

doi:10.1016/s0014-5793(99)00487-1

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PubMed · 10350076

Bleaching of bacteriorhodopsin by continuous light.

Z Dancsházy·Z Tokaji·A Dér

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Abstract

A new two step photobleaching process is observed under continuous illumination of bacteriorhodopsin. This photobleaching is considerable even at physiological temperatures and becomes large at 50-60 degrees C. The photobleaching also increases with increasing pH from 7 to 10. We suggest that the bleaching at its final stage could be due to the dissociation of the retinal and a local thermal denaturation-like process. These facts may question the generally held belief that BR is a stable protein in vivo for a long period of time. Our results may have relevance also to practical applications of bacteriorhodopsin where the stability of bacteriorhodopsin is a key issue. In certain instances, the use of bacteriorhodopsin may require cooled conditions. Here, we defined the conditions under which bacteriorhodopsin is stable. The permanent photobleaching offers a new way of picture imaging and information input for bacteriorhodopsin-based optical devices.

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Bacteriorhodopsins Hydrogen-Ion Concentration Information Storage and Retrieval Light Optical Devices Photochemistry Photons Protein Denaturation Purple Membrane Spectrophotometry Temperature Journal Article Research Support, Non-U.S. Gov't

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Z Dancsházy, Z Tokaji, A Dér. 1999-04-30. Bleaching of bacteriorhodopsin by continuous light.. https://doi.org/10.1016/s0014-5793(99)00487-1

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