Action of penicillin on Aerobacter cloacae.

Hugo, W. B. (University of Nottingham, Nottingham, England), and A. D. Russell. Action of penicillin on Aerobacter cloacae. J. Bacteriol. 82:411-417. 1961.-A study has been made of the action of penicillin on a penicillinase-producing strain of Aerobacter cloacae. It has been found that in culture media rendered hypertonic by the addition of sucrose (0.33 to 0.66 m), provided a source of magnesium ions is present, cell wall lesions occur, giving rise to osmotically fragile spheroplasts. Evidence is also presented of a lethal effect not associated with cell wall damage. Penicillinase production is not a complete challenge to the action of penicillin and in certain experimental situations renders the cells more susceptible to penicillin action.