title: Cell-free synthesis of proteins related to sn-glycerol-3-phosphate transport in Escherichia coli.
abstract: An Escherichia coli periplasmic protein (GlpT) related to sn-glycerol-3-phosphate transport was synthesized in a cell-free system directed by hybrid plasmic ColE1-glpT DNA. The in vitro product cross-reacted with antisera against the purified protein. The ColE1-glpT DNA-directed cell-free system was induced by sn-glycerol-3-phosphate and phosphonomycin and was dependent on cyclic AMP. The in vitro-synthesized protein showed the characteristics of a multimeric protein, as did the purified periplasmic protein. The main proportion of the newly synthesized product had a higher molecular weight than the mature protein found in the periplasm of cells and showed a more positive charge in two-dimensional gel electrophoresis. Thus, a proportion of this protein is presumed to be synthesized in vitro as a precursor. The cell-free system yielded a second protein that is likely to be also coded for by the glpT operon. This protein had a molecular weight of approximately 33,000 in sodium dodecyl sulfate-acrylamide gel electrophoresis and behaved like an intrinsic membrane protein.
mesh_terms: D001426:Bacterial Proteins / Q000096:biosynthesis*; D003086:Bacteriocin Plasmids; D002474:Cell-Free System; D000242:Cyclic AMP / Q000494:pharmacology; D003593:Cytoplasm / Q000378:metabolism; D004269:DNA, Bacterial / Q000378:metabolism; D004352:Drug Resistance, Microbial; D004926:Escherichia coli / Q000187:drug effects / Q000378:metabolism*; D005578:Fosfomycin / Q000494:pharmacology; D005990:Glycerol / Q000378:metabolism; D005991:Glycerol Kinase / Q000378:metabolism; D005994:Glycerophosphates / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D005994:Glycerophosphates; D005578:Fosfomycin; D000242:Cyclic AMP; D005991:Glycerol Kinase; D005990:Glycerol