ProteinProteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, responding to stimuli, providing structure to cells and organisms, and transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the nucleotide sequence of their genes, and which usually results in protein folding into a specific 3D structure that determines its activity.
VirulenceVirulence is a pathogen's or microorganism's ability to cause damage to a host. In most, especially in animal systems, virulence refers to the degree of damage caused by a microbe to its host. The pathogenicity of an organism—its ability to cause disease—is determined by its virulence factors. In the specific context of gene for gene systems, often in plants, virulence refers to a pathogen's ability to infect a resistant host. The noun virulence derives from the adjective virulent, meaning disease severity.
Legionella pneumophilaLegionella pneumophila is a thin, aerobic, pleomorphic, flagellated, non-spore-forming, Gram-negative bacterium of the genus Legionella. L. pneumophila is the primary human pathogenic bacterium in this group and is the causative agent of Legionnaires' disease, also known as legionellosis. In nature, L. pneumophila infects freshwater and soil amoebae of the genera Acanthamoeba and Naegleria. The mechanism of infection is similar in amoeba and human cells. L.
Genetically modified bacteriaGenetically modified bacteria were the first organisms to be modified in the laboratory, due to their simple genetics. These organisms are now used for several purposes, and are particularly important in producing large amounts of pure human proteins for use in medicine. The first example of this occurred in 1978 when Herbert Boyer, working at a University of California laboratory, took a version of the human insulin gene and inserted into the bacterium Escherichia coli to produce synthetic "human" insulin.
Transmutation of speciesTransmutation of species and transformism are unproven 18th and 19th-century evolutionary ideas about the change of one species into another that preceded Charles Darwin's theory of natural selection. The French Transformisme was a term used by Jean Baptiste Lamarck in 1809 for his theory, and other 18th and 19th century proponents of pre-Darwinian evolutionary ideas included Denis Diderot, Étienne Geoffroy Saint-Hilaire, Erasmus Darwin, Robert Grant, and Robert Chambers, the anonymous author of the book Vestiges of the Natural History of Creation.