BACTERIAL GENETICS II - GENETIC
TRANSFER AND ANTIBIOTIC
RESISTANCE EXAM WITH COMPLETE
QUESTIONS AND ANSWERS { GRADED
A+}
Homologous Recombination - ✔✔large regions of sequence identity or
similarity; recipient cell must express recombination enzymes
RecA/RecBC; responsible for the integration of cell-free DNA or
plasmids
Non-Homologous Recombination - ✔✔RecA-independent
recombination; specific sites with no sequence homology required;
specialized enzymes recognize specific nucleotide sequences and
, promote crossover events including transposase, excisase and integrase;
responsible for the integration of Ab gene recombination, phages, and
transposons
Transformation - ✔✔a mechanism of genetic exchange in which naked
bacterial DNA is released by cell lysis and a limited amount is taken up
by the recipient cell; the cell is transformed when the donor DNA is
stably integrated into the recipient's DNA; if there is no homology, the
DNA strand is degraded and nucleotides are recycled; the recipient cell
must be competent in order to be able to uptake cell-free DNA
Competence - ✔✔physiological state that occurs at the late logarithmic
phase of growth in which a cell is able to take up cell-free naked DNA
Gram Positive (Streptococcus/Bacillus) Mode of Competence - ✔✔1.
competence factor induces the synthesis of new proteins
2. autolysin exposes a cell membrane DNA-binding protein
3. DNA-binding protein binds DNA indiscriminately
4. Endonuclease cleaves DNA into 6-8 kb fragments
TRANSFER AND ANTIBIOTIC
RESISTANCE EXAM WITH COMPLETE
QUESTIONS AND ANSWERS { GRADED
A+}
Homologous Recombination - ✔✔large regions of sequence identity or
similarity; recipient cell must express recombination enzymes
RecA/RecBC; responsible for the integration of cell-free DNA or
plasmids
Non-Homologous Recombination - ✔✔RecA-independent
recombination; specific sites with no sequence homology required;
specialized enzymes recognize specific nucleotide sequences and
, promote crossover events including transposase, excisase and integrase;
responsible for the integration of Ab gene recombination, phages, and
transposons
Transformation - ✔✔a mechanism of genetic exchange in which naked
bacterial DNA is released by cell lysis and a limited amount is taken up
by the recipient cell; the cell is transformed when the donor DNA is
stably integrated into the recipient's DNA; if there is no homology, the
DNA strand is degraded and nucleotides are recycled; the recipient cell
must be competent in order to be able to uptake cell-free DNA
Competence - ✔✔physiological state that occurs at the late logarithmic
phase of growth in which a cell is able to take up cell-free naked DNA
Gram Positive (Streptococcus/Bacillus) Mode of Competence - ✔✔1.
competence factor induces the synthesis of new proteins
2. autolysin exposes a cell membrane DNA-binding protein
3. DNA-binding protein binds DNA indiscriminately
4. Endonuclease cleaves DNA into 6-8 kb fragments
