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bacteria

(Encyclopedia)bacteria [pl. of bacterium], microscopic unicellular prokaryotic organisms characterized by the lack of a membrane-bound nucleus and membrane-bound organelles. Once considered a part of the plant king...

denitrifying bacteria

(Encyclopedia)denitrifying bacteria: see nitrogen cycle. ...

nitrifying bacteria

(Encyclopedia)nitrifying bacteria: see nitrogen cycle. ...

nitrogen-fixing bacteria

(Encyclopedia)nitrogen-fixing bacteria: see nitrogen cycle. ...

Archaebacteria

(Encyclopedia)Archaebacteria ärˌkēbăktĭrˈēə [key], diverse group of bacteria (prokaryotes), sometimes called the archaea and considered a major group unto themselves. Archaebacteria are contrasted with the ...

Gram's stain

(Encyclopedia)Gram's stain, laboratory staining technique that distinguishes between two groups of bacteria by the identification of differences in the structure of their cell walls. The Gram stain, named after its...

autotroph

(Encyclopedia)autotroph ôtˈətrōfˌ [key], in biology, an organism capable of synthesizing its own organic substances from inorganic compounds. Autotrophs produce their own sugars, lipids, and amino acids using ...

Lederberg, Joshua

(Encyclopedia)Lederberg, Joshua lāˈdərbûrgˌ [key], 1925–2008, American geneticist, b. Montclair, N.J., grad. Columbia, 1944, Ph.D. Yale, 1948. He is known for his studies of the genetic mechanisms of bacteri...

drug resistance

(Encyclopedia)drug resistance, condition in which infecting bacteria can resist the destructive effects of drugs such as antibiotics and sulfa drugs. Drug resistance has become a serious public health problem, sinc...

erythromycin

(Encyclopedia)erythromycin ĭrĭthˌrōmīˈsĭn [key], any of several related antibiotic drugs produced by bacteria of the genus Streptomyces (see antibiotic). Erythromycin is most effective against gram-positive ...