E.coli cells that have null mutations in the gene encoding mutH will be defective in:
A)base excision repair.
B)mismatch repair.
C)recombinational repair.
D)SOS repair.
E)thymine dimer splitting.

Question

Quizplus · Accepted Answer

MutH is involved in the mismatch repair pathway, which corrects errors that occur during DNA replication such as the incorporation of the wrong nucleotide. Null mutations in mutH will result in a defect in this pathway. Null mutations in the genes encoding base excision repair, recombinational repair, SOS repair, and thymine dimer splitting would result in defects in those specific repair pathways but not affect the mismatch repair pathway.

EColi Cells That Have Null Mutations in the Gene Encoding