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Retrieval or recombination-repair systems in E. coli do NOT use these proteins (______) to perform these (_______) functions?

A. RecBC and RecF; help associate RecA with single-stranded DNA

B. RecA and SSB; bind to double-stranded DNA

C. RecF, RecO and RecR; to repair gaps due to T-T dimers left in after replication in daughter strand

D. RecBC and RecA; restart stalled replication forks

User Poudigne
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Final answer:

The proteins RecA and SSB in E. coli are not involved in binding to double-stranded DNA. RecA facilitates homologous recombination while SSB stabilizes single-stranded DNA during replication and other DNA processes.

Step-by-step explanation:

The correct answer to the question 'Retrieval or recombination-repair systems in E. coli do NOT use these proteins (______) to perform these (_______) functions?' is option B: RecA and SSB; bind to double-stranded DNA. The RecA and SSB proteins have distinct functions related to DNA repair.

Specifically, RecA is important for homologous recombination and is involved in the search for homologous sequences and strand invasion. Single-Stranded Binding proteins (SSB) stabilize single-stranded DNA during processes like DNA replication, preventing the DNA from reforming into a double helix.

These proteins do not typically bind to double-stranded DNA as the functionality of the proteins is related to single-stranded DNA processes. It is noteworthy that RecBC and RecF help associate RecA with single-stranded DNA, RecF, RecO, and RecR are involved in the repair of gaps which may include T-T dimers, and RecBC and RecA can assist in restarting stalled replication forks.

User Sandeep Sudhakaran
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