Chemotaxis
The ability of a cell to detect chemical stimuli and move toward or away from it.
Episomes
A subset of plasmids that are capable of integrating into the genome of the bacteria.
Bacterial Transformation
The integration of foreign genetic material into the host genome.
Bacterial Conjugation
The bacterial form of mating (sexual reproduction). Involves two cells forming a conjugation bridge between them that allows for the transfer of genetic material.
The transfer is unidirectional from the donor male (+) to the recipient female (-) across the conjugation bridge.
Hfr (High Frequency of Recombination)
Refers to bacterial cells that have undergone conjugation (sexual transmission of DNA).
Transduction
The only genetic recombination process that requires a vector - a virus that carries genetic material from one bacterium to another. When a bacteriophage infects another bacterium, it can release this trapped DNA into the new host cell. This transferred DNA can then integrate into the genome, giving the new host additional genes.
Transposons
Genetic elements capable of inserting and removing themselves from the genome. If a transposon is inserted within a coding region of a gene, that gene may be disrupted.
Binary Fission
Process by which bacteria reproduce.
This implies that all of the bacteria are exactly the same in a local colony (assuming no mutations or genetic recombination).
The Four Phases of Bacterial Growth
Lag Phase: adaptation to new environment.
Exponential Phase (Log Phase): exponential increase in the number of bacteria in a colony.
Stationary Phase: result of the reduction of resources, which slows reproduction.
Death Phase: after bacteria have exceeded the ability of the environment to support the number of bacteria.
Bacteriophages
Viruses that specifically target bacteria.