Thermo Scientific pBR322 is one of the more commonly used E. coli cloning vectors.

Product Advantages

• Isolated from Escherichia coli (dam+, dcm+)
• Over 90% supercoiled form
• Purified by chromatography using proprietary patented technology

Applications

• Cloning
• Preparation of DNA Molecular Weight Standard

pBR322 is 4361 bp in length and contains:
• Replicon rep responsible for plasmid replication (source – plasmid pMB1)< br>•ropgene encoding Rop protein, which promotes the conversion of unstable RNA I – RNA II complexes into stable complexes and serves to reduce copy number (source – plasmid pMB1)
• Encodes β -bla gene for lactamase, which confers resistance to ampicillin (source – transposon Tn3)
•tet gene encoding tetracycline resistance protein ( Source – plasmid pSC101)
• The circular sequence is numbered as follows: 1 is the first T of the unique EcoRI site GAATTC, and the number increases as it passes through the tet gene and pMB1 material and finally through the Tn3 region.

This map shows the enzyme that makes one cleavage of pBR322 DNA. Enzymes produced by Thermo Scientific are shown in orange. Coordinates refer to the position of the first nucleotide in each recognition sequence.
The exact location of the genetic element (including the stop codon) is shown in the map. bla gene nucleotides 4153-4085 (complementary strand) encode a signal peptide. The indicated rep regions are sufficient to facilitate replication. DNA replication is initiated at position 2533 (± 1) and proceeds in the direction indicated. Plasmids carrying the pMB1 and ColE1 replicons are incompatible, but they are fully compatible with plasmids carrying the p15A replicon (pACYC177, pACYC184). pMB1-derived plasmids can be amplified using chloramphenicol.