Monoclonal antibody recognizes a conformational epitope in a random coil protein.
Abstract: The antigenic determinants for two monoclonal antibodies directed against horse apo-cytochrome c, a protein of disordered structure, as judged by spectroscopic and hydrodynamic criteria, have been studied by a combination of methods: antigen competition in solution by radio immunoassay and enzyme-linked immunoassay, and differential acetylation of free and antibody-bound antigen. In the latter method the accessibility of lysine residues of the antigen in the antigen-antibody complex is compared to the accessibility in the free antigen. The two antibodies against the heme-free protein do not recognize intact native cytochrome c, but they crossreact with the heme-containing peptides 1-38 and 1-65 of cytochrome c. The antigenic determinant recognized by monoclonal antibody SJL 2-4 is conformational and discontiguous, it is composed of residues close to the N-terminus and around position 25. The other monoclonal antibody, Cyt-1-59, seems to recognize a contiguous epitope close to the N-terminus. The present results show that even a seemingly disordered protein which is conventionally classified as a random coil may feature subtle spatial regularities. The presence of ordered conformational elements in apocytochrome c may be important for the enzyme-catalyzed covalent attachment of the heme and the import of cytochrome c into mitochondria. A discontiguous determinant for SJL 2-4 is particularly interesting because this antibody inhibits the proliferation of a T-cell clone specific for apo-cytochrome c [Corradin & Engers (1984) Nature (Lond.) 308, 547-548].
Publication Date: 1988-12-01 PubMed ID: 2462497DOI: 10.1111/j.1432-1033.1988.tb14446.xGoogle Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
- Journal Article
Summary
This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.
The research explores how two specific antibodies recognize determinants in a seemingly disordered protein, apo-cytochrome c. It uncovers that the protein shows some spatial regularities and that these could play significant roles in biological processes.
Objective and Method of the Experiment
- The research aimed to investigate how two monoclonal antibodies, SJL 2-4 and Cyt-1-59, recognize antigenic determinants within a seemingly disordered protein, the horse apo-cytochrome c. This protein is typically observed as a random coil due to its disordered structure.
- Researchers used antigen competition through radio immunoassay and enzyme-linked immunoassay, and differential acetylation for this investigation. The differential acetylation involved comparing the accessibilities of lysine residues in the antigen within the antigen-antibody complex to those in the free antigen.
Findings from the Experiment
- The two antibodies did not recognize the intact, native cytochrome c. However, they crossreacted with heme-containing peptides of the cytochrome c.
- The monoclonal antibody, SJL 2-4, recognized a conformational and discontiguous determinant, consisting of residues near the N-terminus and around position 25 of the apo-cytochrome c.
- The other monoclonal antibody, Cyt-1-59, seemed to recognize a contiguous epitope close to the N-terminus.
Implications of the Results
- The outcome of the study reveals that there may be subtle spatial regularities in what appears to be a disordered protein. Therefore, even a protein considered as a random coil may feature some structural organization.
- The ordered conformational elements observed in the apo-cytochrome c could be crucial for the enzyme-catalyzed covalent attachment of the heme and the import of cytochrome c into mitochondria.
- The findings are even more noteworthy since the antibody SJL 2-4, which recognized a discontiguous determinant, can inhibit the proliferation of a specific T-cell clone for apo-cytochrome c. This suggests possible therapeutic applications.
Cite This Article
APA
Saad B, Corradin G, Bosshard HR.
(1988).
Monoclonal antibody recognizes a conformational epitope in a random coil protein.
Eur J Biochem, 178(1), 219-224.
https://doi.org/10.1111/j.1432-1033.1988.tb14446.x Publication
Researcher Affiliations
- Biochemisches Institut, Universität Zürich, Switzerland.
MeSH Terms
- Animals
- Antibodies, Monoclonal / immunology
- Antigen-Antibody Reactions
- Apoproteins / immunology
- Binding Sites, Antibody
- Binding, Competitive
- Chromatography, Gel
- Cytochrome c Group / immunology
- Cytochromes c
- Epitopes / immunology
- Heme / immunology
- Horses
- Immunoenzyme Techniques
- Peptide Mapping
- Peptides / analysis
- Peptides / immunology
- Radioimmunoassay
Citations
This article has been cited 3 times.- Guy AJ, Irani V, MacRaild CA, Anders RF, Norton RS, Beeson JG, Richards JS, Ramsland PA. Insights into the Immunological Properties of Intrinsically Disordered Malaria Proteins Using Proteome Scale Predictions. PLoS One 2015;10(10):e0141729.
- Kieliszewski MJ, Leykam JF, Lamport DT. Structure of the Threonine-Rich Extensin from Zea mays. Plant Physiol 1990 Feb;92(2):316-26.
- Saad B, Schawalder H, Maier P. Crude liver membrane fractions as substrate preserve liver-specific functions in long-term, serum-free rat hepatocyte cultures. In Vitro Cell Dev Biol 1993 Jan;29A(1):32-40.
Use Nutrition Calculator
Check if your horse's diet meets their nutrition requirements with our easy-to-use tool Check your horse's diet with our easy-to-use tool
Talk to a Nutritionist
Discuss your horse's feeding plan with our experts over a free phone consultation Discuss your horse's diet over a phone consultation
Submit Diet Evaluation
Get a customized feeding plan for your horse formulated by our equine nutritionists Get a custom feeding plan formulated by our nutritionists
