Trimethoprim: Difference between revisions
No edit summary |
Qchristensen (talk | contribs) (Added content) |
||
Line 1: | Line 1: | ||
==Mode of Action== | ==Mode of Action== | ||
Trimethoprim inhibits folate | Trimethoprim inhibits dihydrofolate reductase, most efficaciously effecting the bacterial enzyme. Bacteria are unable to uptake folate appreciably from rich medium and so must synthesize it themselves. Addition of folate to the medium can counteract trimethoprim, however. | ||
Sulfonilamide effects another step in folate metabolism and so exibits a synergistic effect when used with trimethoprim. | |||
==Resistance Gene== | ==Resistance Gene== | ||
An alternative dihydrofolate Reductase (DHFR) is the gene counteracting trimethoprim. | |||
==Transposon Mutagenesis== | ==Transposon Mutagenesis== | ||
Line 9: | Line 11: | ||
==Working concentrations and stock solutions== | ==Working concentrations and stock solutions== | ||
Working concentrations are typically 10 μg/ml. Trimethoprim is essentially insoluble, | Working concentrations are typically 10 μg/ml. Trimethoprim is essentially insoluble in water, but is soluble in DMSO (check the Merk index or Sigma Catalogue). Addition of the powder is also an option. |
Revision as of 09:58, 26 January 2006
Mode of Action
Trimethoprim inhibits dihydrofolate reductase, most efficaciously effecting the bacterial enzyme. Bacteria are unable to uptake folate appreciably from rich medium and so must synthesize it themselves. Addition of folate to the medium can counteract trimethoprim, however.
Sulfonilamide effects another step in folate metabolism and so exibits a synergistic effect when used with trimethoprim.
Resistance Gene
An alternative dihydrofolate Reductase (DHFR) is the gene counteracting trimethoprim.
Transposon Mutagenesis
Epicentre provides a Tn5 transposon system containing the DHFR gene for random knockouts of genes in bacteria.
Working concentrations and stock solutions
Working concentrations are typically 10 μg/ml. Trimethoprim is essentially insoluble in water, but is soluble in DMSO (check the Merk index or Sigma Catalogue). Addition of the powder is also an option.