Purification and Characterization of an Autolysin from Clostridium acetobutylicum

Abstract

A proteinaceous substance with antibiotic-like activity, resembling that of a bacteriocin, was isolated from an industrial-scale acetone-butanol fermentation of C. acetobutylicum. The substance, purified by acetone precipitation, DEAE chromatography and polyacrylamide gel electrophoresis, was characterized as a glycoprotein with a MW of 28,000. The glycoprotein was partially inactivated by certain protease enzymes. It had no effect on DNA, RNA or protein synthesis and it did not result in the loss of intracellular ATP. The glycoprotein lysed sodium dodecyl sulfate-treated cells and cell wall preparations, and therefore it is referred to as an autolysin. The autolysin gene appeared to be chromosomal since plasmid DNA was not detected in the C. acetobutylicum strain.