• Trimethoprim packaged and labeled.

click on thumbnail to zoom
SKU: T011

Size  
Quantity:
  Click 'Bulk Order' for 10 or more
Price: make selection(s)
Description

Trimethoprim is a synthetic derivative of trimethoxybenzyl-pyrimidine with bacteriostatic and antiprotozoal properties. As a dihydrofolate reductase inhibitor, trimethoprim binds tightly to the bacterial enzyme, blocking the production of tetrahydrofolic acid from dihydrofolic acid, arresting folic acid synthesis.

When Trimethroprim is combined with sulfonamides, like sulfamethoxazole (S045), the two compounds show bactericidal effects, but are only bacteriostatic when used separately. The activity is attributed to their synergistic effect in inhibiting folic acid metabolism in bacteria. 

Trimethoprim has a wide antibacterial spectrum and is active against most gram-positive and gram-negative aerobic bacteria, including NocardiaBrucella, Gram-negative bacilli, and some Gram-positive bacteria like StreptococcusToxoplasma and some other coccidians. It is used to treat recurrent cystitis, mild acute prostatitis, urinary tract infections, asymptomatic bacteriuria during pregnancy and respiratory tract infections.

TOKU-E offers two forms of trimethoprim: trimethoprim (T011) and trimethoprim lactate (T012). Trimethoprim has low solubility in aqueous solution (0.4 mg/mL). Trimethoprim lactate is freely soluble in aqueous solution (19.6 mg/mL).

    CAS Number

    738-70-5

    Molecular Formula

    C14H18N4O3

    Molecular Weight

    290.32

    Mechanism of Action

    Trimethoprim interferes with the cellular metabolism of folic acid in the bacterial cell by blocking the biosynthesis of nucleotides. Trimethoprim binds to dihydrofolate reductase and inhibits the reduction of dihydrofolic acid to tetrahydrofolic acid. Tetrahydrofolic acid is an essential precursor in the thymidine synthesis pathway and interference with this pathway inhibits bacterial DNA synthesis.

    Storage Conditions

    2-8 °C

    Tariff Code

    2933.59.2200

    Spectrum

    Trimethoprim has a wide antibacterial spectrum and is active against most gram-positive and gram-negative aerobic bacteria, including NocardiaBrucella, Gram-negative bacilli, and some Gram-positive bacteria like StreptococcusToxoplasma and some other coccidians. It is used to treat recurrent cystitis, mild acute prostatitis, urinary tract infections, asymptomatic bacteriuria during pregnancy and respiratory tract infections.

Applications

    Microbiology Applications

    Trimethoprim is commonly used in clinical in vitromicrobiological antimicrobial susceptibility tests (panels, discs, and MIC strips) against gram positive and gram negative microbial isolates. Medical microbiologists use AST results to recommend antibiotic treatment options for infected patients. Representative MIC values include:

    • Escherichia coli 0.25 µg/mL - 64 µg/mL
    • Haemophilus influenzae 0.15 µg/mL - 16 µg/mL
    • For a complete list of trimethoprim MIC values, click here.

    Media Supplement

    Trimethoprim can be used as a selective agent in several types of isolation media:

    Columbia Blood Agar - Campylobacter selective supplement (Skirrow)

    Columbia Blood Agar - Campylobacter selective supplement (Blaser-Wang)

    Campylobacter Agar - Campylobacter Selective Supplement (Preston)

    Columbia Blood Agar - Helicobacter pylori Selective Supplement (Dent)

    Bolton Broth - Bolton Broth Selective Supplement

    Campylobacter Agar Base - Modified Preston Campylobacter Selective Supplement

    Bolton Broth - Modified Bolton Broth Selective Supplement

    ChromogenicBacillus cereus Agar - Chromogenic Bacillus cereus Selective Supplement

    Plant Biology Applications

    Trimethoprim can be used in combination with rifampicin to provide sufficient coverage against pathogenic microbes. When used without other supplemental antibiotics, trimethoprim was not shown to provide sufficient coverage (Pollock et al.1983).

Specifications

    Form

    Powder

    Appearance

    White or yellowish-white powder

    Melting Point

    199°C - 203°C

    Assay

    (On Dried Basis): 98.5 - 101.0%

    Loss on Drying

    Not more than 0.5%

    Residue On Ignition

    Not more than 0.1%

References

    References

    Weir, D. G., and J. Scott. "Mechanism of the Antimicrobial Drug Trimethoprim Revisited."PubMed (2000): 2519-524. www.ncbi.gov. 14 Dec. 2000. Web. 21 Aug. 2012.

Other Items In This Category

Related Products