1) Consider the following DNA template strand: 3'TACTATCGAGTC5'
Give the complementary DNA sequence, the mRNA transcript, and the polypeptide.
mRNA transcript: 5'AUGAUAGCUCAG3'
Polypeptide: met - ile - ala - gln
2) An aliquot of 1 x 108 E. coli cells from a strain
unable to synthesize arginine, lysine, and serine were plated on complete
medium, forming a bacterial lawn. Replica plates were then made onto
minimal medium supplemented by pairs of the three amino acids. Give
the full genotypes of the new mutants.
arg- lys- ser+ arg+ lys- ser-
3) A bacterial strain unable to synthesize methionine (met-) was transduced by a strain unable to synthesize isoleucine (ileu-). Half the resulting broth culture was plated on minimal medium supplemented with isoleucine, the other half was plated on minimal medium alone. A total of 29 clones appeared on the miminal plates and 320 on the isoleucine plates. What is the map distance?
4) At time zero a wild-type Hfr strain sensitive to streptomycin was mated
to an strep-resistant F- strain mutant at eight loci: a-b-c-d-e-f-g-h-.
Samples were removed at intervals, agitated, and plated on selective media
containing streptomycin. Draw a genetic map from the following results:
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