Bacterial and Viral Genetics Flashcards
What are the 3 types of DNA transfer
Conjugation, Transduction and Transformation
In which cell (diploid or haploid) is it easier to observe mutations and why?
haploid are easy to identify due to loss-of-function mutations (usually gametes). They reproduce asexually through gene transfer
what is the process of conjugation?
transfer of DNA from one bacteria to another following direct cell-to-cell contact
what cells can act as donor cells
only strains of bacteria that contain the F factor can act as a donor cell.
what’s an F factor
it is a small circular piece of DNA, the ones containing the F factor is designated as F+
- F= cell to F- cell
What are sex pilus
they act as attachment sites for other bacteria
Made only by F+ strains
-helps create conjunction bridge
What is transduction?
the transfer of DNA between bacteria via a bacteriophage
what is a bacteriophage
they are viruses that specifically attack bacteria
What is the process of transformation?
it is when a bacterium takes up extracellular DNA in its environment
What are the two types of transformation?
natural transformation
artificial transformation
does natural transformation require help?
DNA uptake occurs without outside help and occurs in a wide variety of bacteria
what are competent cells?
they carry genes that encode proteins called competence factors that facilitate the binding, uptake and subsequent incorporation of the DNA into the bacterial chromosome
what enzyme cuts up the DNA in transformation in bacterial DNA
endonuclease enzymes
what are plasmids?
they are DNA that exist independently of the chromosomal DNA
what are the plasmids that can integrate into the chromosome?
episome
