SEQUENCE CONSERVATION OF LIGHT-HARVESTING AND STRESS-RESPONSE PROTEINS IN RELATION TO THE 3-DIMENSIONAL MOLECULAR-STRUCTURE OF LHCII

The structure of pea light-harvesting complex LHCII determined to 3.4 Angstrom resolution by electron crystallography (Kuhlbrandt, Wang and Fujiyoshi (1994) Nature 367: 614-621) was examined to determine the re lationship between structural elements and sequence motifs conserved i n the extended family of light-harvesting antennas (Chl a/b, fucoxanth in Chl a/c proteins) and membrane-intrinsic stress-induced proteins (E LIPs) to which LHCII belongs. It is predicted that the eukaryotic ELIP s can bind at least four molecules of Chi. The one-helix prokaryotic F LIP of Synechococcus was modelled as a homodimer based on the high deg ree of conservation of residues involved in the interactions of the fi rst (B) and third (A) helices of LHCII.