bacterium (redirected from Gram-negative bacterium)

bac·te·ri·um  (bk-tîr-m)

n. pl. bac·te·ri·a (-tîr-)

Any of the unicellular prokaryotic microorganisms of the class Schizomycetes, which vary in terms of morphology, oxygen and nutritional requirements, and motility, and may be free-living, saprophytic, or pathogenic in plants or animals.

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[New Latin bactrium, from Greek baktrion, diminutive of baktron, rod; see bak- in Indo-European roots.]

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bacterium  (bk-tîr-m)

Plural bacteria

Any of a large group of one-celled organisms that lack a cell nucleus, reproduce by fission or by forming spores, and in some cases cause disease. They are the most abundant lifeforms on Earth, and are found in all living things and in all of the Earth's environments. Bacteria usually live off other organisms. Bacteria make up most of the kingdom of prokaryotes (Monera or Prokaryota), with one group (the archaea or archaebacteria) often classified as a separate kingdom. See also archaeonprokaryote

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bacterial adjective

Usage It is important to remember that bacteria is the plural of bacterium, and that saying a bacteria is incorrect. It is correct to say The soil sample contains millions of bacteria, and Tetanus is caused by a bacterium.

Thesaurus

Noun

1.

bacterium - (microbiology) single-celled or noncellular spherical or spiral or rod-shaped organisms lacking chlorophyll that reproduce by fission; important as pathogens and for biochemical properties; taxonomy is difficult; often considered to be plants bacteria immune reaction, immune response, immunologic response - a bodily defense reaction that recognizes an invading substance (an antigen: such as a virus or fungus or bacteria or transplanted organ) and produces antibodies specific against that antigen bioremediation - the act of treating waste or pollutants by the use of microorganisms (as bacteria) that can break down the undesirable substances micro-organism, microorganism - any organism of microscopic size acidophil, acidophile - an organism that thrives in a relatively acid environment probiotic, probiotic bacterium, probiotic flora, probiotic microflora - a beneficial bacterium found in the intestinal tract of healthy mammals; often considered to be a plant bacteroid - a rodlike bacterium (especially any of the rod-shaped or branched bacteria in the root nodules of nitrogen-fixing plants) eubacteria, eubacterium, true bacteria - a large group of bacteria having rigid cell walls; motile types have flagella Calymmatobacterium, genus Calymmatobacterium - a genus of bacterial rods containing only the one species that causes granuloma inguinale Francisella, genus Francisella - a genus of Gram-negative aerobic bacteria that occur as pathogens and parasite in many animals (including humans) gonococcus, Neisseria gonorrhoeae - the pus-producing bacterium that causes gonorrhea legionella, Legionella pneumophilia - the motile aerobic rod-shaped Gram-negative bacterium that thrives in central heating and air conditioning systems and can cause Legionnaires' disease nitrobacterium - any of the bacteria in the soil that take part in the nitrogen cycle; they oxidize ammonium compounds into nitrites or oxidize nitrites into nitrates penicillin-resistant bacteria - bacteria that are unaffected by penicillin pus-forming bacteria - bacteria that produce pus rod - any rod-shaped bacterium diplococcus - Gram-positive bacteria usually occurring in pairs superbug - a strain of bacteria that is resistant to all antibiotics resistance - the degree of unresponsiveness of a disease-causing microorganism to antibiotics or other drugs (as in penicillin-resistant bacteria) microphage - a neutrophil that ingests small things (as bacteria) microbiology - the branch of biology that studies microorganisms and their effects on humans