BIOL 205 Lecture Notes - Lecture 5: Hfr Cell, Transposable Element, Cas9
Document Summary
Where it;"s integrated, it never puts entire chromosomal dna. Crossovers integrate parts of the transferred donor fragment. Transferred fragment is converted into a double helix. Linear transmission of the hfr genes from a fixed point. At specific times, take samples out and throw into blender. This is known as interrupted mating, as the pili are fragile and cannot mate. Plate the blended culture on streptomycin to kill hfr cells. Test cells for azi, ton, lac, gal. Analysis of auxotrophic markers -> chromosome is circular. A single crossover inserts f at a specific locus, which then determines the order of gene transfer. The integration site determines the order of gene transfer. Each donor allele first appears in the f- recipients at a specific time after mating began. The donor alleles appear in a specific sequence. Later donor alleles are present in fewer recipient cells.