Microbiology terms - T
- taxis
- Movement toward or away from a stimulus.
- taxon (plural taxa)
- A group into which related organisms are classified.
- taxonomy
- The study of scientific classification and nomenclature.
- T cell
- See T lymphocyte.
- T cell receptor
- The antigen-specific receptor on the surface of T lymphocytes.
- T-DNA
- The segment of the Agrobacterium Ti plasmid which is transferred to plant
cells.
- T lymphocyte
- A type of immune cell responsible for many cell-mediated immune responses
plus stimulation of differentiation of antibody-producing lymphocytes (i.e. B
cell) during the humoral immune response.
- termination
- 1. Stop of mRNA synthesis (i.e., transcription) at the terminator site
2. Stop of protein synthesis (i.e., translation) at the stop codon.
- terminator
- The site on a DNA sequence at which the process of transcription stops.
- temperate virus
- A virus which upon infection of a host does not necessarily cause lysis but
whose genome may replicate in synchrony with that of the host. See lysogen
- tertiary structure
- The final folded structure of a polypeptide that has previously attained
secondary structure.
- thermocline
- Zone of water in a stratified lake in which temperature and oxygen
concentration drop precipitously with depth.
- Ti plasmid
- A conjugative plasmid present in the bacterium Agrobacterium
tunmefaciens which can transfer genes into plants.
- tick-borne disease
- The diseases transmitted by ticks such as Rocky Mountain spotted fever, Q
fever, and Lyme disease.
- titer
- Measure of antibody quantity.
- tolerance
- In reference to immunology, the acquisition of nonresponsiveness to a
molecule normally recognized by the immune system.
- toxic shock symdrome
- Acute shock resulting from host response to an exotoxin produced by
Staphylococcus aureus.
- toxigenicity
- The degree to which an organisms is able to elicit toxic symptoms.
- toxin
- A microbial substance able to induce host damage.
- toxoid
- A toxin modified so that it is no longer toxic but is still able to induce
antibody formation.
- transcription
- Synthesis of an RNA molecule complementary to one of the two strands of
a double-stranded DNA molecule.
- transduction
- Transfer of host genetic information via a virus (or bacteriophage) particle.
- transfection
- The transformation of a prokaryotic cell by DNA or RNA from a virus.
Used also to describe the process of genetic transformation in eukaryotic
cells.
- transfer RNA (tRNA)
- A type of RNA that carries amino acids to the ribosome during translation;
contains anticodon.
- transformation
- 1. Transfer of genetic information into a prokaryotic cell via free DNA.
2. A process initiated by infection with certain viruses, whereby a normal
animal cell becomes a cancer cell.
- transgenic
- Used to describe genetically modified plants or animals containing foreign
genes inserted by means of recombinant DNA techniques.
- translation
- The synthesis of protein using the genetic information in a messenger RNA
as a template.
- transpeptidation
- The formation of peptide bonds betweent the short peptides present in the
cell wall polymer, peptidoglycan.
- transposable element
- A genetic element that has the ability to move (transpose) from one site on a
chromosome to another.
- transposition
- The movement of a piece of DNA around the chromosome, usually through
the function of a transposable element.
- transposon
- A type of transposable element which, in addition to genes involved in
transposition, carries other genes; often conferring selectable phenotypes
such as antibiotic resistance.
- transposon mutagenesis
- Insertion of a transposon into a gene; this inactivates the host gene leading to
a mutant phenotype and also confers the phenotype associated with the
transposon gene.
- tricarboxylic acid cycle (= TCA cycle, citric acid cycle, Krebs cycle)
- A series of metabolic reactions by which pyruvate is oxidized completely to
carbon dioxide, also forming NADH, which allows ATP production.
- trichome
- A trichome is a row of cells which have remained attached to one another
following successive cell divisions. The cells in the trichome are usually
separated by septa but some of the adjacent cells can communicate with one
another via small pores (microplasmodesmata) which are not found in a
simple chain of bacterial cells such as chains of streptococci. The cells of a
trichome may or may not be covered by a common sheath. Trichomes are
formed by many cyanobacteria and e.g. by species of Beggiatoa.
- tuberculin test
- A test for previous infection with Mycobacterium tuberculosis.
- tumor
- Excessive tissue caused by uncontrolled cell growth.
Compiled by Tsute Chen, Converted by Ben Hoyt