title: 30-S ribosomal subunit proteins of an Escherichia coli mutant in which assembly of the small ribosomal subunit is temperature-sensitive.
abstract: Escherichia coli 219ts2, a temperature-sensitive streptomycin-independent revertant of the streptomycin-dependent strain E. coli 209 is defective in 30-S ribosomal subunit assembly at 42 degrees C. Total 30-S ribosomal subunit proteins of this strain contain two additional components one of which (alpha) migrates below and the other (beta) to the right of protein S7 in two-dimensional polyacrylamide gel analyses carried out according to Kaltschmidt and Wittmann. These two components are also resolved from normal 30-S subunit proteins by chromatography on phosphocellulose. Tryptic fingerprinting of proteins alpha and beta identifies alpha as protein S7B, the form of S7 found in B strains of E. coli and beta as a mutant form of protein S4 produced by deletion of about 20 amino acids from the COOH terminus of the wild-type protein.
mesh_terms: D000596:Amino Acids / Q000032:analysis; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000378:metabolism*; D046911:Macromolecular Substances; D008970:Molecular Weight; D009154:Mutation; D010446:Peptide Fragments / Q000032:analysis; D012269:Ribosomal Proteins / Q000378:metabolism*; D012270:Ribosomes / Q000378:metabolism*; D013696:Temperature
chemical_list: D000596:Amino Acids; D046911:Macromolecular Substances; D010446:Peptide Fragments; D012269:Ribosomal Proteins