title: Partial Purification and Characterization of a Bacteriocin Produced by Propionibacterium thoenii.
abstract: A partially purified bacteriocin produced by Propionibacterium thoenii designated propionicin PLG-1 was found to be active against closely related species and exhibited a broad spectrum of activity against other microorganisms. Propionicin PLG-1 was found to be heat labile, sensitive to several proteolytic enzymes, and stable at pH 3 to 9. Propionicin PLG-1 was isolated from solid medium, partially purified by ammonium sulfate precipitation, and purified further by gel filtration. Gel filtration experiments revealed that bacteriocin PLG-1 was present as two different protein aggregates with apparent molecular weights of more than 150,000 and approximately 10,000. Resolution of these protein aggregates by sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed the presence of a protein common to both with an apparent molecular weight of 10,000.
authors.affiliation: Department of Microbiology and Department of Food Science and Human Nutrition, Iowa State University, Ames, Iowa 50011.
authors.forename: W J
authors.initials: WJ
authors.lastname: Lyon
authors.forename: B A
authors.initials: BA
authors.lastname: Glatz