Studies on the functional topography of Escherichia coli RNA polymerase. Highly selective affinity labelling by analogues of initiating substrates.

摘要: A method is proposed for localization of the sites affinity labelling β subunit Escherichia coli RNA polymerase. The principle this similar to that methods rapid sequencing nucleic acids. The polypeptide bearing a radioactive label at one amino acid residues subjected short-term treatment with cyanogen bromide. conditions reaction are selected in such way less than cleavage occurs on average per chain. Two series peptides formed, involving all possible N-terminal and other C-terminal peptides. distribution lengths these studied by means gel electrophoresis compared theoretical ones based known sequence subunit. Obviously, resides between C-terminus shortest peptide N-terminus peptide. In order increase reliability resolution method, partial trypsinolysis may be employed. The evidence obtained suggests lysine over regions 1036–1066, 1234–1242, histidine-1237 situated nearest neighbourhood to, or directly involved formation active center initiating substrate binding E.