Chloroplast SecA and Escherichia coli SecA have Distinct Lipid and Signal Peptide Preferences

Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT 06269-3125 USA

^* To whom correspondence should be addressed. Email: debra.kendall{at}uconn.edu.

	Abstract

Like prokaryotic Sec-dependent protein transport, chloroplasts utilize SecA. However, we observe distinctive requirements for stimulation of chloroplast SecA ATPase activity; it is optimally stimulated in the presence of galactolipid and only a low fraction of anionic lipid, and by Sec-dependent thylakoid signal peptides but not Escherichia coli signal peptides.