Answers 2024/2025
what applies to bacteriophages? - ANSWERSBacteriophages recognize molecules on bacterial surface to
infect
All phages use the hosts replication machinery to some extent
Most phages have narrow host range
Bacteriophage genomes can be RNA, but mostly DNA
In vitro transcription of the SARS-2 spike gene makes use of the __________ - ANSWERST7 gp10
promoter
The antirestriction protein of T7: - ANSWERSprotects T7 DNA from bacterial endonucleases
What is the enzymatic function of gene product 1 in T7? - ANSWERSmRNA synthesis
Which phage-encoded protein catalyzes the formation of phosphodiester bonds between nucleotides? -
ANSWERSDNA ligase
In the pET system for recombinant protein expression, in the absence of IPTG: - ANSWERSBinding of T7
RNA polymerase to the gp10 promoter is obstructed
Which gene or feature is employed in the pET system? - ANSWERST7 gp10 promoter
LacI
, T7 RNA polymerase
plac
What is a major advantage of bacteriophages as antimicrobial agents over small molecule antibiotics? -
ANSWERSless killing of friendly human bacteria
What is a pathogenic bacterial genus for which a bacteriophage is being developed for treatment, and is
commonly implicated in bacterial food poisoning? - ANSWERSlisteria
escherichia
salmonella
What applies more to generalized than to specialized transduction? - ANSWERSLacks site specificity for
integration in the bacterial chromosome
specialized transduction - ANSWERSDNA of the host bacterium tends to get completely degraded
Preferentially transfers only a certain region of the bacterial chromosome
Mostly bacterial sequences close to attB site are transferred during transduction
The transducing phage tends to have a very narrow host range
Which event in bacteriophage lambda will favor lysis over lysogeny? - ANSWERSIncreased expression of
the cro repressor
Which event in bacteriophage lambda will favor lysogeny? - ANSWERSAntitermination mediated by T
protein
Autocleavage of CRO dimers upon contact with RecA-ssDNA nucleoprotein