bacterium

(noun)

A single celled organism with no nucleus.

Related Terms

Examples of bacterium in the following topics:

  • Botulism

    • Botulism is a rare but sometimes fatal paralytic illness caused by botulinum toxin produced by the bacterium Clostridium botulinum.
    • This toxin is a protein produced under anaerobic conditions by the bacterium Clostridium botulinum.
    • In all cases, illness is caused by the botulinium toxin produced by the bacterium C. botulinum in anaerobic conditions, and not by the bacterium itself.
    • This occurs in small children who are colonized with the bacterium during the early stages of their lives.
    • The bacterium then releases the toxin into the intestine, which is absorbed into the bloodstream.

  • Bacterial Transduction

    • Transduction is the process by which DNA is transferred from one bacterium to another by a virus.
    • Transduction is the process by which DNA is transferred from one bacterium to another by a virus .
    • This bacterial material may become recombined into another bacterium upon infection.
    • Specialized transduction is the process by which a restricted set of bacterial genes are transferred to another bacterium.
    • Transduction is the process by which DNA is transferred from one bacterium to another by a virus.

  • Plasmids and Lysogeny

    • Lysogeny is the process by which a bacteriophageintegrates its nucleic acids into a host bacterium's genome.
    • The virus displays the ability to infect the bacterium host and integrate its own genetic materials into the host bacterium genome.
    • The prophage is integrated into the bacterium genome at this point.
    • The lysogenic cycle is key to ensure the transmittance of bacteriophage nucleic acids to host bacterium's genome.
    • This bacterium is then able to produce a cholera toxin, the cause of the disease cholera .

  • Introduction to Plasmids

    • The upper half of the image shows a bacterium with its chromosomal DNA and plasmids dividing into two identical bacteria, each with their chromosomal DNA and plasmids.
    • The lower half of the image shows a bacterium with its chromosomal DNA, but with an episome.
    • Next to this bacterium, we see the same bacterium, but after the episome has integrated into the chromosomal DNA and has become a part of it.
    • This second bacterium now divides into two bacteria identical to it, each with an episome integrated into it.

  • Hosts for Cloning Vectors

    • The majority of molecular cloning experiments begin with a laboratory strain of the bacterium E. coli (Escherichia coli) as the host.
    • A very large number of host organisms and molecular cloning vectors are in use, but the great majority of molecular cloning experiments begin with a laboratory strain of the bacterium E. coli (Escherichia coli) and a plasmid cloning vector.

  • Whooping Cough

    • The bacterium contains a surface protein, filamentous haemagglutinin adhesin, which binds to the sulfatides found on the cilia of epithelial cells.
    • Once anchored, the bacterium produces tracheal cytotoxin, which stops the cilia from beating.
    • The bacterium is spread by airborne droplets, and its incubation period is one to two weeks.

  • Tularemia

    • Tularemia (also known as Pahvant Valley plague, rabbit fever, deer fly fever, and Ohara's fever) is a serious infectious disease caused by the bacterium Francisella tularensis.
    • A Gram-negative, nonmotile coccobacillus, the bacterium has several subspecies with varying degrees of virulence.
    • Francisella tularensis is an intracellular bacterium, meaning it is able to live as a parasite within host cells.
    • Tularemia is caused by the bacterium, Francisella tularensis.

  • Listeriosis

    • Listeriosis is a bacterial infection caused by a Gram-positive, motile bacterium called Listeria monocytogenes.
    • Listeriosis is a bacterial infection caused by a Gram-positive , motile bacterium, Listeria monocytogenes.
    • A bacterial infection caused by a Gram-positive, motile bacterium, Listeria monocytogenes which is shown here on a blood agar plate.

  • Anthrax

    • Anthrax is an acute disease caused by the bacterium Bacillus anthracis.
    • Bacillus anthracis is a rod-shaped, Gram-positive, aerobic bacterium about 1 by 9 micrometers in length.
    • The bacterium normally rests in endospore form in the soil, and can survive for decades in this state.
    • Once ingested or placed in an open wound, the bacterium begins multiplying inside the animal or human and typically kills the host within a few days or weeks.

  • Deinococcus and Thermus

    • Deinococcus radiodurans is an extremophilic bacterium, one of the most radioresistant organisms known.
    • It has been listed as the world's toughest bacterium in The Guinness Book of World Records.
    • Deinococcus radiodurans is an extremophilic bacterium, one of the most radioresistant organisms known.
    • D. radiodurans is a rather large, spherical bacterium, with a diameter of 1.5 to 3.5 µm.
    • This bacterium is a chemotroph — it performs chemosynthesis to obtain food.