In Vitro Interaction between a Chloroplast Transit Peptide and Chloroplast Outer Envelope Lipids Is Sequence-specific and Lipid Class-dependent

Abstract

Interaction of artificial lipid bilayers (liposomes) with the purified transit peptide (SS-tp) of the precursor form of the small subunit for ribulose-2,5-bisphosphate carboxylase/oxygenase (prSSU) has been studied using a vesicle-disruption assay (calcein dye release) and electron microscopy. Employing purified forms of Escherichia coli-expressed prSSU, mature small subunit, glu-

Non-native, N-terminal Hsp70 Molecular Motor Recognition Elements in Transit Peptides Support Plastid Protein Translocation

“…Further experimentation and mutagenesis may uncover how these peptides interact with artificial membranes mimicking the chloroplast outer envelope. It has already been shown that the N-ter of SStp can interact with lipids and undergo a conformational change (12,14) that may be involved in the initial reversible binding step.…”

Comparative topical delivery of antifungal drug croconazole using liposome and micro-emulsion-based gel formulations

“…The EE of the drug in the prepared liposome (MLVs or SUVs) was observed in the range of 53-70%. The EE of sonicated liposome was found to be higher which could be due to lower size of sonicated liposomes (Pinnaduwage & Bruce, 1996;Were et al, 2003). However, prepared micro-emulsions (ME1 and ME2) showed the particle size in the range of 40-45 nm with high degree of homogeneity (PI-0.1).…”

Protein import into chloroplasts

“…The outer chloroplast envelope is strongly negatively charged and enables formation of ionic interactions between preproteins and lipids on the chloroplast surface (Fulgosi and Soll, 2001). Both inner and outer chloroplast envelope membranes are composed of unusual lipids, including monogalactosyldiacylglycerol (MGDG), digalactosyldiacylglycerol (DGDG), sulfolipid sulfoqinovosildiacylglycerol (SQDG) and negatively charged phosphatidylglycerol (PG) (Joyard et al, 1991, Pinnaduwage and Bruce, 1996). The lipid/protein ratio of the outer membrane is very high (around 3) (Block et al, 1983) and has a direct influence on protein binding and import across the chloroplast envelopes.…”