Purification of cloned proaerolysin released by a low protease mutant of Aeromonas salmonicida.
The precursor to the hole-forming toxin aerolysin has been purified in high yield from culture supernatants of a mutant of Aeromonas salmonicida containing the cloned structural gene. The mutant strain was generated by Tn5 mutagenesis. It released little or no protease or other extracellular proteins, including phospholipase, suggesting that it is a regulatory mutant. The absence of protease allowed the isolation of protoxin free from contaminating aerolysin. Typically, more than 50 mg of pure proaerolysin was obtained from 2 L of culture supernatant. The purified protein was completely unable to lyse human erythrocytes without prior activation with trypsin.
Department of Biochemistry and Microbiology, University of Victoria, B.C., Canada.
J T
JT
Buckley
D000333:Aeromonas / Q000201:enzymology / Q000235:genetics*; D001427:Bacterial Toxins / Q000235:genetics / Q000302:isolation & purification*; D003001:Cloning, Molecular; D004591:Electrophoresis, Polyacrylamide Gel; D005798:Genes, Bacterial; D006460:Hemolysin Proteins / Q000302:isolation & purification*; D006801:Humans; D009154:Mutation; D010447:Peptide Hydrolases / Q000235:genetics*; D052899:Pore Forming Cytotoxic Proteins; D011498:Protein Precursors / Q000235:genetics / Q000302:isolation & purification*; D011994:Recombinant Proteins / Q000302:isolation & purification
D001427:Bacterial Toxins; D006460:Hemolysin Proteins; D052899:Pore Forming Cytotoxic Proteins; D011498:Protein Precursors; D011994:Recombinant Proteins; C032676:aerolysin; D010447:Peptide Hydrolases