Question

In vector pBR 322, the ‘rop’ codes for the

• A. Pvu II
• B. proteins that involved in the replication of the restriction enzyme
• C. Pvu I
• D. proteins that involved in the replication of the plasmid

Answer 1

The correct option is D proteins that involved in the replication of the plasmid

Vectors are the DNA molecules which can carry the foreign DNA fragment into the host cells for cloning. Examples include plasmids.

pBR322 is the most common plasmid vector. It is named after Bolivar and Rodriguez.

Common features of pBR322 are as follows:

• Restriction sites - It has multiple restriction sites for different restriction enzymes such as Pvu II, Pvu I, BamH I, EcoR I, Hind III, Pst I, Sal I, Cla I, etc.
• Rop - It is a specific base sequence that codes for the rop protein involved in the replication of the plasmid. ‘Rop’ stands for the ‘repressor of primer’ and the main function of the rop protein is to control the copy number of plasmid.
• Selectable markers - It has two selectable markers, one for ampicillin resistance amp^R and one for tetracycline resistance tet^R.
• Ori - It has an ori site or origin of replication site. Any piece of DNA when linked to this sequence can be made to replicate within the host cells.

Pictorial representation of pBR322


Hence the correct option is
d. proteins that involved in the replication of the plasmid