Exam 1 - Ch.7 - Microbial Genetics Flashcards
Small molecules of extra-chromosomal DNA that replicate independently.
plasmids
Are plasmids essential for normal metabolism, growth, or reproduction?
NO
What can plasmids do?
Can covert survival advantage.
What are the 4 types of plasmids?
F plasmids
R plasmids
Bacteriocin factors
Virulence plasmids
What are F plasmids?
Fertility factors - carry instructions for conjugation.
What are R plasmids?
Resistance factors - carry genes for resistance to anitbiotics
What are bacteriocin factors?
Carry genes for toxins called bacterions - can kill its competitors.
What are virulence plasmids?
Carry instructions that enable bacteria to become pathogenic. “good bacteria go bad”
What is it called when organisms replicate their genome and provide copies to descendants?
Vertical gene transfer
What type of cells do we see vertical gene transfer?
Prokaryotes and Eukaryotes (normal process in both)
What is it called when genes are acquired from other microbes of the SAME generations?
Horizontal gene transfer
How does horizontal gene transfer work?
donor cell contributes part of genome to recipient cell - may be a different species.
What are the three types of horizontal gene transfer (Prokaryotes)?
Transformation
Transduction
Bacterial conjugation
Horizontal gene transfer where recipient cell takes up DNA from environment. (not specific - scavenger)
Transformation
In transformation what are the cells that take up DNA called?
Competent (must have particular “skill set”)
What type of horizontal gene transfer is transfer of DNA from one cell to another via a replicating virus called?
Transduction
In transduction, what is it called when the transducing phage carries random DNA segment from donor to recipient?
Generalized transduction
In transduction, what is it called when only certain DNA sequences are transferred?
Specialized transduction
What is a virus that attacks bacteria called?
bacteriophage
What is the phage with the donor DNA called?
Transducing phage
In transduction, how is the donor DNA incorporated into the recipient’s chromosome?
By recombination
The type of horizontal gene transfer that transfers DNA from one cell to another, mediated by conjugation pili?
Conjugation
Donor cell in conjugation requires what type of plasmid?
F plasmid (F+)
Does the recipient cell have F plasmid?
NO
What happens during bacterial conjugation?
A strand of F plasmid DNA is transferred to the recipient and the recipient can now do bacterial conjugation as well. (“female” becomes “male”)
