THE SOCIETY FOR GENERAL MICROBIOLOGY

Summary: Oxidation of several substrates by whole or broken organisms of Micrococcus lysodeikticus was arrested following treatment with lysozyme, unless an osmotic stabilizer (sorbitol) were present. Whole organisms, which did not oxidize NADH2, and broken organisms (which oxidized NADH2 only slowly) oxidized NADH2 readily after lysozyme treatment, though the activity was maintained only in presence of an osmotic stabilizer. Lysozyme treatment similarly allowed whole or broken M. lysodeikticus to oxidize (mammalian) cytochrome c, or to reduce this cytochrome with appropriate electron-donors, e.g. lactate, succinate, or NADH2. Most of these observations held good also for the lysozyme-sensitive Bacillus megaterium, but not for several lysozyme-insensitive organisms (both Gram-positive and Gram-negative).