Vector IG Sequence Link :
General : plasmid ds-DNA 1167 BP
Functions : (cloning)
Selection : ()
Copy Number :
Hosts : (E.coli)
Suppliers : ()
Misc.Comments : Dihydrofolate reductase (DHFR) is a highly conserved enzyme; the DHFRs encoded by the bacterial and animal genomes are similar to each other in size, amino acid sequence, and active site residues. In contrast, the plasmid-encoded type II DHFR and the bacterial chromosomal enzymes have different active sites and apparently distinct origins. Four BamHI linker insertion mutants were utilized as part of the sequencing strategy. Sites of insertion that destroyed the methotrexate resistance fell in two regions; one of these regions encodes a 78 amino acid polypeptide homologous to another drug-resistant DHFR, the second region essential for DHFR expression appears to be the promoter of the DHFR gene. The DHFR amino acid sequence derived from the DNA sequence is closely homologous to that of the R67 DHFR (see seperate entry), but differs in 17 of the 78 amino acid residues. NCBI gi: 207843
Parents : (R388 from E. coli RR1)
Siblings : ()
Descendents : ()


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