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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...

antiseptic

(Encyclopedia)antiseptic, agent that kills or inhibits the growth of microorganisms on the external surfaces of the body. Antiseptics should generally be distinguished from drugs such as antibiotics that destroy mi...

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 ...

chemosynthesis

(Encyclopedia)chemosynthesis, process in which carbohydrates are manufactured from carbon dioxide and water using chemical nutrients as the energy source, rather than the sunlight used for energy in photosynthesis....

pus

(Encyclopedia)pus, thick white or yellowish fluid that forms in areas of infection such as wounds and abscesses. It is constituted of decomposed body tissue, bacteria (or other micro-organisms that cause the infect...

bacteriophage

(Encyclopedia)bacteriophage băktērˈēəfājˌ [key], virus that infects bacteria and sometimes destroys them by lysis, or dissolution of the cell. Bacteriophages, or phages, have a head composed of protein, an i...

episome

(Encyclopedia)episome ĕpˈĭsōm [key], unit of genetic material composed of a series of genes that sometimes has an independent existence in a host cell and at other times is integrated into a chromosome of the c...