micrococcus

—micrococcal, micrococcic /muy'kreuh kok"sik/, adj.

/muy'kreuh kok"euhs/, n., pl. micrococci /-kok"suy, -see/. Bacteriol.

any spherical bacterium of the genus Micrococcus, occurring in irregular masses, many species of which are pigmented and are saprophytic or parasitic.

[ < NL (1872); see MICRO-, COCCUS]

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Any of the spherical bacteria that make up the genus Micrococcus.

Widespread in nature, these gram-positive (see gram stain) cocci (see coccus) are usually not considered to cause disease. They are normal inhabitants of the human body and may even be essential in keeping the balance among the various microorganisms found on the skin. Some species are found in the dust of the air, in soil, in marine waters, and on the skin of vertebrates. Certain species are found in milk and can result in spoilage.

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▪ bacteria genus

 genus of spherical bacteria in the family Micrococcaceae that is widely disseminated in nature. Micrococci are microbiologically characterized as gram-positive cocci, 0.5 to 3.5 μm (micrometres; 1 μm = 10^-6 metre) in diameter.

      Micrococci are usually not pathogenic. They are normal inhabitants of the human body and may even be essential in keeping the balance among the various microbial flora of the skin. Some species are found in the dust of the air (M. roseus), in soil (M. denitrificans), in marine waters (M. colpogenes), and on the skin or in skin glands or skin-gland secretions of vertebrates (M. flavus). Those species found in milk, such as M. luteus, M. varians, and M. freudenreichii, are sometimes referred to as milk micrococci and can result in spoilage of milk products.

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