Lecture 34: Microbial Genetics Flashcards
List 3 properties of bacterial genome:
- Typically a singular circular chromosome
- No nuclear membrane
- Small circular DNA molecules known as Plasmids
What is the region called that the chromosome in a bacterial cell is confined to known as?
Nucleoid region
What are 2 types of gene transfer amongst bacteria?
- Horizontal gene transfer
- Vertical gene transfer
What is horizontal gene transfer?
Transferring genes from one organism directly to another
What is vertical gene transfer?
Transferring genes from ‘parent’ to ‘offspring’
What are the 3 types of horizontal gene transfer?
- Transformation
- Transduction
- Conjugation
Outline the features of conjugation.
- Bacteria use a sex pilus, that attach to another bacteria
- plasmids unwind and are fed through the pilus to another bacteria
Outline the features of transformation.
Naked DNA fragments find their way into another bacteria
Outline the features of transduction.
Phage virus bind and inject their DNA into bacteria
Outline the lytic cycle.
- Phage inserts its DNA
- replicates using the bacteria’s machinery
- Cell lyses releases newly assembled phages
Outline the Lysogenic cycle.
- Phage DNA integrates with bacterial DNA
- Cell replication creates more bacteria containing bacterial chromosome