The charge state of substrates and inhibitors when bound to Lactobacillus casei dihydrofolate reductase [proceedings].

Binding to Lactobacillus casei Dihydrofolate Reductase

The u.v. difference spectra generated when methotrexate, trimethoprim or folate bind to Lactobacillus casei dihydrofolate reductase were analysed. The difference spectrum produced by methotrexate binding is shown to consist of three components: (a) one closely resembling that observed on protonation of methotrexate, reflecting an increased degree of protonation on binding; (b) a pH-independent ...

Dihydrofolate reductase: partial sequence of the Lactobacillus casei enzyme and homology with other dihydrofolate reductases [proceedings].

DNA binding by dihydrofolate reductase from Lactobacillus casei.

The protein-dependent retention of double-stranded DNA molecules on nitrocellulose filters has been used to show that pure dihydrofolate reductase from Lactobacillus casei has affinity for DNA. Dihydrofolate reductase will bind to end-labeled linear double-stranded DNA and to DNA in supercoiled form. Coenzymes and certain inhibitors do not affect the affinity of the protein to DNA, indicating t...

Characterization of the DNA binding region recognized by dihydrofolate reductase from lactobacillus casei.

Two specific DNA binding sites for the enzyme dihydrofolate reductase from Lactobacillus casei have been located by means of an immunoprecipitation assay within a 2900-base pair L. casei DNA fragment containing the L. casei dihydrofolate reductase structural gene, which was previously cloned into pBR322. The inserted L. casei DNA was mapped using restriction endonucleases, and the location and ...

Immunochemical evidence for extensive ligand-induced conformational changes in Lactobacillus casei dihydrofolate reductase.

The effects of ligand binding on antibody complex formation of Lactobacillus casei dihydrofolate reductase have been investigated. Binary complexes containing either substrate and inhibitors or NADP+ and NADPH together with ternary complexes containing inhibitors and coenzyme were examined. Whereas substrate and inhibitor binding alone show no effect, the binding of coenzyme reduces antibody co...