Chapter 9 Flashcards
What is conjugation?
Transfer of genetic material between donor and recipient bacteria through sex pills
Where can bacteria be grown?
Liquid culture, or agarose plates (isolated from seaweed)
Prototrophic vs Auxotrophic bacteria
Prototrophic bacteria are wild type and can synthesize all the compounds they need for survival. Auxotrophic bacteria are mutant and require a medium supplemented with nutrients.
Bacterial Genome consists of:
Most bacteria have a single, circular DNA chromosome with plasmids also present
What are episomes?
Plasmids that can replicate freely but also integrate into bacterial genome
What is transformation?
A bacterium takes up DNA from the medium in which it is growing
What is transduction?
Bacteriophages carry DNA from one bacterium to another
F factor conjugation
F factor nicked at an origin. Nicked strand moves to F- cell and replicates. F- cell is now F+ cell.
HFr conjugation
F factor (integrated into chromosome) is nicked, and 5’ end moves into recipient. Chromosome follows into recipient, replicates, and crosses over with recipient DNA.
F’ Plasmid
F factor that integrated with bacterial chromosome, but was excised, taking some bacterial genes with it
F’ to F- conjugation
F’ plasmid transferred, creating two merozygotes (or partially diploid), as some genes are found on both F factor and bacterial gene
What are competent cells?
Cells that take up DNA
What are transform ants?
cells that receive genetic material
What does cotransformed mean?
Cells that are transformed by two or more genes
Process of transformation
Double stranded DNA approaches cell, but only one strand can enter. Strand recombines with bacterial chromosome. When the cell divides, one daughter cell has the recombinant chromosome.
