Microbial Genetics Flashcards
Properties of the Bacterial Genome
Single circular chromosome
No nuclear membrane
Other small circular self replicating DNA molecules can be found in the cytosol
What is the area where the chromosome is restricted to?
The chromosome is restricted to defined region of the bacterial cell known as the nucleoid
What is horizontal gene transfer?
Only bacteria can do this
One living bacteria takes a part of its DNA and transports it to another different bacteria
Plasmids are being transferred
What is vertical gene transfer?
Only way mammals can transfer genetic material
Bacteria can also do this
Transfer genetic material to offspring
How does Griffiths classic experiment demonstrate horizontal gene transfer?
Smooth forms (infected) of bacteria is treated with heat and mixed with rough forms (healthy)
DNA/plasmids from treated smooth form has gone inside rough forms producing infected smooth form
What are virulence factors?
Attributes that help bacteria survive in the host, sometimes at a cost to the host
How do capsules protect bacteria?
Capsules protect bacteria from being phagocytosed by white blood cells allowing for continuous growth
What is antibiotic resistance?
Attributes that reduce the effectiveness of antibodies against the targeted bacteria
How does a plasmid make a bacteria drug resistant?
Transfer of one plasmid to another can make a bacteria completely drug resistant as a single plasmid can contain many multiple resistance factor genes
What is transformation?
One form transformed to another
Some bacteria are partially capable of sucking up naked DNA from the environment
Uptake of DNA by living bacteria
What is conjugation?
Involves the sex pilus to transfer of plasmids from one bacteria to another
Requires cell to cell contact
What is transduction?
Involves the phage virus that particularly infects bacteria only and have molecular arrangements that only enable it to infect specific types of bacteria
Transfer of DNA from bacteria to another via phage viruses
What is the phage therapy?
The therapeutic use of bacteriophages to resist pathogenic bacterial infections
