In E. coli, the primary component of the mismatch repair system is the protein MutS. How does MutS recognize mismatched base pai

Question

10 days ago

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In E. coli, the primary component of the mismatch repair system is the protein MutS. How does MutS recognize mismatched base pai

rs?
(a)-It reads the major groove and counts the number of hydrogen bonds to determine if there is correct base pairing.
(b)-When mismatched base pairs are transcribed, MutS edits the RNA transcript to correct the mutation.
(c)-It recognizes purine-purine and pyrimidine-pyrimidine mismatches because they are, respectively, longer and shorter than a purine-pyrimidine pair.
(d)-It identifies hemimethylated base pairs and methylates the unmodified base.
(e)-When subjected to force, mismatched base pairs distort more easily than correctly matched basepairs.

Biology

1 answer:

-BARSIC- [1.9K] · Answer 1 · 2026-03-19T18:10:05+03:00

Answer:

The most accurate answer to the inquiry, based on findings regarding this specific mechanism in E. Coli, is: D) It detects hemimethylated base pairs and extends the methylation to the unmethylated base.

Explanation:

Research into this complex subject, particularly in E. Coli and other gram-negative prokaryotes, indicates that whether or not methylation is present will trigger MutS, a protein present in both prokaryotes and eukaryotes that plays a crucial role in launching and executing the entire DNA mismatch repair operation. When daughter DNA strands are synthesized from the parent strands, these initial strands often contain various mismatches and deletions that require rectification, identifiable because the daughter strands are hemimethylated. This situation prompts MutS in E. Coli to attach to the damaged DNA strand, and accompanied by other complex members like MutH and MutL, it starts the repair process.

The exact methodology by which MutS repairs DNA in eukaryotes and different prokaryotic organisms remains not entirely elucidated.