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Clostridium

(Encyclopedia)Clostridium, genus of gram-positive bacteria (see Gram's stain), several species of which cause significant, potentially deadly diseases in humans as a result of the toxins that each produces. Clostri...

streptomycin

(Encyclopedia)streptomycin strĕpˌtōmīˈsĭn [key], antibiotic produced by soil bacteria of the genus Streptomyces and active against both gram-positive and gram-negative bacteria (see Gram's stain), including s...

streptococcus

(Encyclopedia)streptococcus strĕpˌtəkŏkˈəs [key], any of a group of gram-positive bacteria, genus Streptococcus, some of which cause disease. Streptococci are spherical and divide by fission, but they remain ...

gangrene

(Encyclopedia)gangrene, local death of body tissue. Dry gangrene, the most common form, follows a disturbance of the blood supply to the tissues, e.g., in diabetes, arteriosclerosis, thrombosis, or destruction of t...

Metchnikoff, Élie

(Encyclopedia)Metchnikoff, Élie ālēˈ mĕchˈnĭkôf [key], 1845–1916, Russian biologist. He studied in Russia and Germany, lectured at the Univ. of Odessa, and, after working with Pasteur in Paris, became (19...

antibiotic

(Encyclopedia)antibiotic, any of a variety of substances, usually obtained from microorganisms, that inhibit the growth of or destroy certain other microorganisms. Although for centuries preparations derived from ...

deodorizer

(Encyclopedia)deodorizer or deodorant, substance used to absorb or eliminate offensive odors. Disinfectants such as hydrogen peroxide, chlorine, and chlorine compounds eliminate odors caused by microorganisms. Adso...

Monera

(Encyclopedia)Monera, taxonomic kingdom that comprises the prokaryotes (bacteria and cyanobacteria). Prokaryotes are single-celled organisms that lack a membrane-bound nucleus and usually lack membrane-bound organe...

colitis

(Encyclopedia)colitis, inflammation of the colon, or large intestine. The term “colitis” may be used to refer to any of a number of disorders involving the colon. Symptoms include diarrhea (often with blood and...

Leeuwenhoek, Antony van

(Encyclopedia)Leeuwenhoek, Antony van änˈtōnē vän lāˈvənho͞okˌ [key], 1632–1723, Dutch student of natural history and maker of microscopes, b. Delft. His use of lenses in examining cloth as a draper's a...