FACTORS MODIFYING INDUCED FORMATION OF PENICILLINASE IN STAPHYLOCOCCUS AUREUS
Abstract
CONTENT ALERTS Receive: RSS Feeds, eTOCs, free email alerts (when new articles cite this article), more» Information about commercial reprint orders: http://jb.asm.org/site/misc/reprints.xhtml To subscribe to to another ASM Journal go to: http://journals.asm.org/site/subscriptions/ HARRY G. Laboratory of Clinical Investigation, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland Received for publication November 21, 1960 Penicillinase, which is encountered in many penicillin-resistant strains of Staphylococcus aureus isolated from man (Kirby, 1944), is an inducible enzyme in Bacillus cereus and other species of this genus (Poilock, 1950). It was considered for a time as noninducible in S. aureus (Bondi et al., 1954). Subsequently, evidence was presented by Geronimus and Cohen (1957) supporting the hypothesis that the enzyme in S. aureus is also inducible. The present report verifies the inducibility of staphylococcal penicillinase and describes some of the factors controlling the induction process. MATERIALS AND METHODS Preparation of cells. The test organism was a penicillin-resistant strain of S. aureus isolated from a patient at the Clinical Center of the National Institutes of Health. It was of the phage pattern 80/81, coagulase positive, a strong a-hemolysin producer, and was resistant to a variety of antibiotics at the time of the primary isolation. A