Prof. Martin Engelhard
Max Planck Institute of Molecular Physiology
Dortmund, Germany

Friday, March 7, 2003
11:00 am (CT)
3269 Beckman Institute

Abstract

Sensory rhodopsin II, a repellent phototaxis receptor from Natronobacterium pharaonis (NpSRII), is a member of the family of microbial rhodopsins. Excitation by light triggers a conformational change in the transmembrane domain of its cognate transducer (NpHtrII) which subsequently is transferred to the tip of the cytoplasmic domain, thereby activating the cellular two component signalling cascade. In membranes NpHtrII and NpSRII form a 2:2 complex which dissociates to a tightly bound 1:1 complex in micelles. The structure of the complex has been determined and will be discussed in respect to a mechanism of signal transduction across the membrane.

Tea and coffee will be served in R3151 Beckman Institute at 2:15pm.