Immunoaffinity purification of the Escherichia coli rne gene product. Evidence that the rne gene encodes the processing endoribonuclease RNase E.

摘要: The rne gene product was highly purified from Escherichia coli cells overproducing the protein by a procedure including immunoaffinity chromatography. Expression in vivo and vitro of cloned 6-kilobase pair DNA fragment containing entire resulted synthesis migrating as 180-kDa polypeptide SDS-polyacrylamide gel. position on two-dimensional polyacrylamide gel indicated that is acidic. enzymatic activity test which used substrate RNA I 9 S provided evidence structural for processing enzyme RNAse E. Western blot analysis performed using rabbit antiserum raised against truncated 110-kDa RNase E (containing two-thirds sequence N terminus) revealed only recognized antibodies wild type whole cell extract coli. cross-reacted with similar molecular weight proteins number different bacteria, suggesting evolutionarily conserved bacterial world.