Photoaffinity cross-linking of acyl carrier protein to Escherichia coli membranes.
Acyl Carrier Protein (ACP) is a small acidic protein which interacts with the various enzymes implicated in the biosynthesis of fatty acids in E. coli. It also interacts with the inner membrane proteins implicated in the biosynthesis of phospholipids. Samples of radioactive ACP were prepared with high specific activities and bearing photoactivable aryl azide derivatives. Two photoactivable reagents were used: para azido phenacyl bromide (pAPA) which reacts with the SH of the ACP prosthetic group and the N-hydroxysuccinimide ester of 4-azido salicylic acid (NHS-ASA) which reacts with the amino groups of the protein. Various methods were used to demonstrate that ACP could be cross-linked specifically to an inner membrane protein of E. coli, most probably to the glycerol-3-phosphate acyl transferase (GPAT). This covalent link should provide a powerful tool for further analysis of the structure of GPAT and its role in phospholipid biosynthesis. These photoactivable aryl azide derivatives of ACP could also be very useful for studying the interaction of ACP with the soluble enzymes implicated in fatty acid biosynthesis.
Bayan
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Laboratoire des Biomembranes, UA 1116, Université Paris Sud, Orsay, France.
Thérisod
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D000213:Acyl Carrier Protein / Q000138:chemical synthesis / Q000737:chemistry* / Q000187:drug effects; D000345:Affinity Labels; D002462:Cell Membrane / Q000201:enzymology; D003432:Cross-Linking Reagents / Q000737:chemistry / Q000494:pharmacology; D004926:Escherichia coli / Q000737:chemistry* / Q000201:enzymology; D007457:Iodine Radioisotopes; D008565:Membrane Proteins / Q000737:chemistry; D011956:Receptors, Cell Surface / Q000737:chemistry
D000213:Acyl Carrier Protein; D000345:Affinity Labels; D003432:Cross-Linking Reagents; D007457:Iodine Radioisotopes; D008565:Membrane Proteins; D011956:Receptors, Cell Surface