Chapter 5: Bacterial Transformation & Polymerase Chain Reaction

What is the clinical significance of bacterial transformation in biotechnology?

explains antibiotic resistance spread, enables genetic engineering, and underlies gene therapy vectors

When did Griffith discover transformation?

1928

How did the mouse die in station 1?

from pneumonia

What did the S-strain contain?

polysaccharide capsule which enabled immune evasion

How was the R-strain different from the S-strain?

the R-strain is uncapsulated while the S-strain is capsulated

What happened in station 3 of griffith’s experiment?

heat killed the S-strain and the mouse survived

What happened in station 4?

The mouse dies from pneumonia, blood samples show living, encapsulated S strain

How did the bacteria demonstrate genetic variation?

in demonstrated genetic transformation

What happens during DNA release and uptake in the transformation process?

foreign DNA is incorporated through cell membrane

What happens during DNA integration?

complementary strand integrates via homologous recombination

What happens during bacterial division in the transformation process?

dividing bacterium replicates hybrid chromosome with S strain

What is the clinical significance of bacterial conjugation?

drives antibiotic resistance spread in hospital settings

What are the different bacterial mating types?

F+ and F- bacterium, F+ and F- chromosome

What is the fertility factor?

episomal DNA conferring donor ability

What is the conjugation bridge?

cells creating direct contact for plasmid transfer

How are genes transferred during conjugation?

through the pilus

What is high frequency recombination?

transfers chromosomal DNA

What is bacterial transduction?

enables bacteriophage to transfer genetic material between bacteria

What happens during bacteriophage attachment?

recognizes receptor sites on bacterial surface

What happens during phage DNA replication?

bacterial machinery is used for viral Genome amplification and multiple copies of phage DNA form

What happens during packaging and phage release?

cell lysis releases mixture of normal phages and error occurs when phage protein coat covers bacterial DNA instead of phage DNA

What are the steps of generalized transduction?

donor bacterium harbors integrated prophage DNA, temperate phage integrates at specific attachment sites, and aberrant excision removes phage DNA with flanking bacterial genes

What happens during prophage integration and excision?

donor bacterium harbors integrated prophage DNA, temperate phage integrates at specific attachment sites, and aberrant excision removes phage DNA with flanking bacterial genes

What is hybrid DNA formation?

How is DNA transferred to recipient?

What is the pre-integratiom state?

What is the post-integration state?

What is the clinical significance of Bacterial Transduction?

How did genetic engineering revolutionize medicine?

What is the donor plasmis?

What are restriction enzymes?

What are DNA ligase?

Where do foreign DNA come from?

What is a chimera?

What does CaCl₂ solution do to cells?

How does the host bacteria reproduce quickly?

How can recombinant proteins be used?

How did PCR revolutionize medicine?

What are primers?

What are dNTPs?

What is taq polymerase?

What are the three steps of PCR?

What temp does annealing happen?

hat happens during annealing phase?

What temp does elongation happen at?

What occurs during elongation stage?

How does PCR multiply? (mathematical formula)

How many cycles of PCR are typical?