title: Effects of Precise Deletions in Rhodobacter sphaeroides Reaction Center Genes on Steady-state Levels of Reaction Center Proteins: A Revised Model for Reaction Center Assembly.
abstract: Possible interactions between photosynthetic reaction center (RC) proteins that protect these membrane proteins from proteolytic digestion in RC complex assembly were evaluated by use of translationally in-frame (nonpolar) RC gene-specific deletions. The RC H, RC M and RC L proteins were produced from plasmids, either alone or in concert with one or both of the others, in a strain of Rhodobacter sphaeroides that contained chromosomal deletions of all three RC genes. The steady-state amounts of these proteins in cell membrane and soluble fractions were assessed in western blots. The data are used to propose a model of RC assembly in which the RC M protein accumulates in the cell membrane regardless of the presence of the RC H and RC L proteins, and the RC M protein is a nucleus for addition of RC L followed by RC H in assembly of the RC holocomplex.
authors.affiliation: Department of Microbiology and Immunology, University of British Columbia, 300-6174 University Blvd, Vancouver, British Columbia, Canada, V6T 1Z3, jbeatty@interchange.ubc.ca.
authors.forename: Ali
authors.initials: A
authors.lastname: Tehrani
authors.forename: J
authors.initials: J
authors.lastname: Thomas Beatty