Lipid—peptide interactions between fragments of the transit peptide of ribulose‐1,5‐bisphosphate carboxylase/oxygenase and chloroplast membrane lipids

Abstract

Lipid-peptideEnteraetisms between fragments of the transit peptide of ribulase-1,5bisphosphate sarboxgrlase/oxygsmase and chloroplast membrane lipids Received 5 August 1991The mteractlons of fragments of the transit peptide of r~bulose-I $blsphosphate carboxylase/oxygenase with hp~d monolayers was studied In order to mvestlgate the possible mvolvement of the membrane hplds m the pro&m Import peocess The fragments are surface active and have a differential ablhty to Insert m hpld monolayees The fragments have a preference for the chloroplast galacto-and sulphohplds and phosphatldylglycerol and Interact with envelope membrane hptd extracts These results suggest that probably transu peptlde-hpld InteractIons aec mvolvcd III the chloroplast protem Import process Chloroplast protem Import, Trdnslt peptlde, Pepttde-hpld mteractlon, Galactohpld. Sulphohpld, Small subumt of rlbulosc-l,5-blsphosphatr: carboxylaselovygenase

Protein import into chloroplasts

“…A possible function of lipids in the import process can be assumed easily because envelope membranes have a unique lipid composition, containing high amounts of the phospholipids phosphatidylcholine and phosphatidyglycerol as well as the specific chloroplast galactolipids, monogalactosyldiacylglycerol and digalactosyldiacylglycerol and the sulpholipid, sulphoquinovosyldiacylglycerol. Recently Van't Hof et al (48) reported that fragments representing different parts of the transit peptide of pSSU interact specifically with lipids typically present in the outer chloroplast envelope, indicating that transit peptide-lipid interactions could play a certain role in a productive chloro-plast protein import pathway. In contrary Endo et al (49) showed that the chloroplast-targeting domain of PC transit peptide has only low affinity for lipid bilayers consisting of galactolipids and phospholipids to mimick the lipid composition of chloroplast envelope membranes, but can form a helical structure in a hydrophobic environment.…”

Galactolipid deficiency and abnormal chloroplast development in the Arabidopsis MGD synthase 1 mutant

“…The mgd1 mutant therefore represents a unique resource for studying the role of MGD in different photosynthetic processes in vivo. It will also prove invaluable as attempts are made to assess the role of MGD in other important processes in which it has been proposed to play a role, such as the translocation of nucleus-encoded proteins across the plastid envelope (31)(32)(33).…”

Transit sequence‐dependent binding of the chloroplast precursor protein ferredoxin to lipid vesicles and its implications for membrane stability

“…Precursor proteins bind to chloroplasts in the absence of ATP [3] and after protease pretreatment of chloroplasts [4]. Furthermore, it was shown in model membrane studies that precursor proteins and transit peptides can interact in a specific way with lipids from the target membrane [5,6]. For instance, lipid monolayer studies showed that the precursor protein of ferredoxin (prefd) inserts, transit sequence-dependent, efficiently and specifically in between the lipids extracted from the chloroplast outer envelope membrane [6].…”