Production of the enzyme dihydrofolate reductase by methotrexate-resistant bacteria isolated from soil

✍ Scribed by Poonam Nigam; Roger Marchant

• Publisher: Wiley (John Wiley & Sons)
• Year: 2007
• Tongue: English
• Weight: 449 KB
• Volume: 56
• Category: Article
• ISSN: 0268-2575
• DOI: 10.1002/jctb.280560107

✦ Synopsis

Abstract

Six bacterial cultures isolated from soil were capable of growing in the presence of methotrexate (MTX). Two strains, PFR‐1 and 3, developed resistance to 500 μg cm^−3^ MTX in the medium and produced elevated levels of the enzyme dihydrofolate reductase (EC 1.5.1.3): 2580 and 2702 U dm^−3^ compared to the sensitive parent strains (28 and 35 U dm^−3^). Isolate PFR‐3 showed maximum enzyme production (4950 U dm^−3^, specific activity 12.56 U mg^−1^ in flasks and 5737 U dm^−3^, specific activity 14.80 U mg^−1^ in 5‐dm^3^ fermenter) during exponential phase of growth (6 h) at 37°C and pH 7.0.