产品名称

Dihydrofolate Reductase human

一般描述

Human DHFR is an 186 amino acid protein with an apparent molecular weight of 25 kDa. It is 30% homologous to the E. coli protein and up to 70% homologous to vertebrate proteins.

别 称

DHFR, Tetrahydrofolate NADP₊ oxidoreductase

含 量

≥80% (SDS-PAGE), recombinant, expressed in  E. coli, ≥1 units/mg protein

浓 度

0.02-0.06 mg/mL

MDL  number

MFCD00130955

适用范围

生物试剂

l  理化信息

外 观

无色的甘油溶液

物理形态

Solution in 10 mM Tris pH 8, 1 mM EDTA, 0.5  mM DTT, 5 μM NADPH, protease inhibitors, and 50% glycerol.

l  生物学信息

生物活性/药理作用

Km_5,6

NADPH 0.16 mM

7,8-dihydrofolate 0.03 mM

8-methylpterin 0.13 mM

Ki₇

Folate 2.6x10_-5 mM

Methotrexate 6.1_-9x10_-9

The human DHFR gene, as well as DHFR genes in other mammalian species, overcome the inhibitory effects of methotrexate by a mechanism of gene amplification or by amino-acid mutagenesis. Dihydroflate reductase (DHFR) catalyzes the NADPH dependent reduction of dihydrofolate (DHF) to tetrahydrofolate (THF) and, at a much lower rate, the conversion of folate to THF. The reaction product, THF, is an essential cofactor in the conversion of deoxyuridylate (dUMP) to deoxythymidylate (dTMP) by thymidylate synthetase. It is a key enzyme in thymidine synthesis. Therefore, DHFR is a critical enzyme in DNA synthesis and has become a target  for drug development and cancer therapy. The variations between DHFR from different sources have enabled the development of species selective DHFR  inhibitors, such as trimethoprim (antibacterial and antifungal), pyrimethamine (antiprotozoal), and methotrexate; MTX (antineoplastic, antipsoriatic, and anti-inflammatory).

应 用

Dihydrofolate reductase (DHFR) is a key enzyme in thymidine synthesis. It catalyzes the reduction of dihydrofolate (DHF) to tetrahydrofolate (THF). At a much lower rate, it catayzes the conversion of folate to THF. Since thymidine is a necessary substrate for DNA synthesis, DHFR is a target for anticancer drug development. Methotrexate is the prototype dihydrofolate reductase inhibitor. The enzyme from Sigma has been used in the inhibitory studies of Leishmaniasis donovani pteridine reductase 1 (PTR1). The enzyme has also been used as a positive control to measure the DHFR activity of a protein, MS0308, purified from Mycobacterium smegmatis. Human dihydrofolate reductase has been used in a study to investigate the stable of green fluorescent protein and the targeted disruption of thioredoxin peroxidase-1 gene in Babesia bovis. Human dihydrofolate reductase has also been used in a study to investigate the structural analysis of human dihydrofolate reductase as a binary complex.

有效单位定义

One unit will convert 1.0 μmole of dihydrofolic acid to tetrahydrofolic acid in 1 minute at pH 7.5 at 22 °C.

l  存储

存储温度

-20 °C

l  注意事项及免责声明

本产品仅用于实验研究，不得作为药物使用，不得用于家用或其它用途。

l  参考文献

1.    http://www.drugbank.ca

2.    https://ncit.nci.nih.gov

3.    https://www.ncbi.nlm.nih.gov