ABSTRACT
An anti-idiotypic antibody approach was used to identify chloroplast and mitochondrial protein component(s) which interact with the corresponding signal sequence. The proteins thus identified can be operationally defined as receptor(s) for import of proteins into chloroplasts and mitochondria. The import receptor(s) was found in "contact sites" between the outer and inner membrane of chloroplast envelope or of mitochondria.
Subject(s)
Antibodies, Anti-Idiotypic , Biological Transport , Chloroplasts/metabolism , Fabaceae , Fungal Proteins/metabolism , Membrane Proteins/immunology , Mitochondria/metabolism , Plant Proteins/metabolism , Plants, Medicinal , Protein Sorting Signals/metabolism , Receptors, Cell Surface/metabolism , Receptors, Cytoplasmic and Nuclear , Receptors, Peptide , Ribulose-Bisphosphate Carboxylase/immunology , YeastsABSTRACT
Dextran was covalently coupled to neutral unilamellar liposomes. Dextran conjugated liposomes were cleared from the circulation at a much slower rate than unconjugated liposomes. The uptake of dextran conjugated liposomes by liver and spleen was also decreased. The amount of dextran on the surface of liposomes was found to be a determining factor for their stability in circulation. Dextran conjugated liposomes therefore may be a more effective way of controlled drug release.
ABSTRACT
The binding of Ricinus communis agglutinin and Abrus agglutinin to 4-methylumbelliferyl β-D-galactopyranoside was studied by equilibrium dialysis, fluorescence quenching and fluorescence polarization. The number of binding sites and the association constant value obtained by fluorescence polarization for both Ricinus communis agglutinin and Abrus agglutinin are in close agreement with those obtained by the other methods. This indicates the potential of ligand-fluorescence polarization measurements in the investigation of lectin-sugar interactions.