Jan 25, 1984

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

The Journal of Biological Chemistry
A M GronenbornG M Clore


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 complex formation. The most striking effect is observed with ternary complexes containing methotrexate or aminopterin and NADPH: maximal retention of the labeled protein in the immunoprecipitation assay is reduced to approximately 30% of its original value with dihydrofolate reductase alone due to a decrease in both the affinity and lifetime of the antibody-protein complex at one or more antigenic sites. This result is discussed in terms of different conformational changes brought about by NADP and NADPH.

  • References
  • Citations


  • We're still populating references for this paper, please check back later.
  • References
  • Citations


  • This paper may not have been cited yet.

Mentioned in this Paper

Ligand Binding
Complex (molecular entity)
Protein Complex Location
Protein Conformation
Immune complex
Tetrahydrofolate Dehydrogenase

About this Paper

Related Feeds

Antibody Specificity

Antibodies produced by B cells are highly specific for antigen as a result of random gene recombination and somatic hypermutation and affinity maturation. As the main effector of the humoral immune system, antibodies can neutralize foreign cells. Find the latest research on antibody specificity here.

ASBMB Publications

The American Society for Biochemistry and Molecular Biology (ASBMB) includes the Journal of Biological Chemistry, Molecular & Cellular Proteomics, and the Journal of Lipid Research. Discover the latest research from ASBMB here.