Question

Which of the following is not a characteristic of pBR322 vector?

• A. It is the first artificial cloning vector constructed in 1977 by Boliver and Rodriguez
• B. It is the most widely used, versatile and easily manipulated vector
• C. It has two antibiotic resistance genes, $te{t}^R$ and $am{p}^R$
• D. It does not have restriction site for Sal I

Answer 1

The correct option is D It does not have restriction site for Sal I

The pBR322 is the first artificial cloning vector. The p in pBR322 stands for plasmid. BR stands for Bolivar and Rodriguez, two of the scientists who constructed the pBR322 cloning vector in 1977. The number 322 distinguishes this vector from other vectors developed in their laboratory.

The pBR322 vector was developed from E. coli. It contains restriction sites (Hind III, EcoR I, BamH I, Sal I, Pvu II, Pst I, Cla I), ori (origin of replication) and two antibiotic resistance genes ($am{p}^R$ and $te{t}^R$ ). It also contains a region rop which codes for the proteins involved in the replication of the plasmid. The recognition sites for Sal I and BamH I are present within its tetracycline resistance gene ($te{t}^R$). While Pvu II, Pst I recognition sites are within ampicillin resistance gene ($am{p}^R$).