ELECTRON MICROSCOPY OF ULTRATHIN SECTIONS OF MICROCOCCUS CRYOPHILUS

Abstract
Ultra thin sections of Micrococcus cryophilus cells were investigated. The cell wall, consisting of several layers, measures 410–500 Å and is covered with a distinct capsule. The cytoplasm, which is of granular structure, includes ribosomes, condensed chromatin, and occasionally mesosomes. The nuclear material has various shapes and is formed by filaments proceeding in various directions. We could find no evidence to bear out the supposition of Kocur and Martinec (1962) that M. cryophilus is related to Micrococcus luteus. M. cryophilus is, in its structure as well as its groupings of cells, different from micrococci, which leads us to believe that it does not belong to the genus Micrococcus.