Showing papers by "Serge Muyldermans published in 1999"
TL;DR: Biochemical, structural and antigen binding characterisation properties of both camel VH domains and camelised human VH domain suggest that these can compete successfully with single chain variable domain (Fv) fragments from conventional antibodies in many applications.
300 citations
TL;DR: The presence of the heavy‐chain antibodies and the possibility of immunizing a dromedary allows for the production of antigen binders consisting of a single domain only, which has two additional advantages: the camel or llama derived single domain antibodies might be an ideal scaffold for anti‐idiotypic vaccinations; and the development of smaller peptides or peptide mimetic drugs derived from of the antigen binding loops might be facilitated due to their less complex antigen binding site.
Abstract: The humoral immune response of camels, dromedaries and llamas includes functional antibodies formed by two heavy chains and no light chains. The amino acid sequence of the variable domain of the naturally occurring heavy-chain antibodies reveals the necessary adaptations to compensate for the absence of the light chain. In contrast to the conventional antibodies, a large proportion of the heavy-chain antibodies acts as competitive enzyme inhibitors. Studies on the dromedary immunoglobulin genes start to shed light on the ontogeny of these heavy-chain antibodies. The presence of the heavy-chain antibodies and the possibility of immunizing a dromedary allows for the production of antigen binders consisting of a single domain only. These minimal antigen-binding fragments are well expressed in bacteria, bind the antigen with affinity in the nM range and are very stable. We expect that such camelid single domain antibodies will find their way into a number of biotechnological or medical applications. The structure of the camelid single domain is homologous to the human VH, however, the antigen-binding loop structures deviate fundamentally from the canonical structures described for human or mouse VHs. This has two additional advantages: (1) the camel or llama derived single domain antibodies might be an ideal scaffold for anti-idiotypic vaccinations; and (2) the development of smaller peptides or peptide mimetic drugs derived from of the antigen binding loops might be facilitated due to their less complex antigen binding site.
217 citations
TL;DR: A new canonical structure for the H1 loop of immunoglobulins, with c Ab-RN05 and cAb-Lys3 as reference structures is defined, which might also occur in human or mouse VH domains.
198 citations
TL;DR: In this article, the authors determined the molecular basis for the absence of the C(H)1 domain in naturally occurring heavy-chain antibodies of the camelids was assessed by determining the entire Camelus dromedarius gamma2a constant gene.
120 citations
TL;DR: The three‐dimensional structure of rat pancreatic RNase A expressed in Escherichia coli was determined and it was inferred that the local conformation of the substrate governs the specificity of subtilisin.
Abstract: The three-dimensional structure of rat pancreatic RNase A expressed in Escherichia coli was determined. The backbone conformations of certain critical loops are significantly different in this enzyme compared to its bovine counterpart. However, the core structure of rat RNase A is similar to that of the other members of the pancreatic ribonuclease family. The structural variations within a loop bordering the active site can be correlated with the subtle differences in the enzymatic activi- ties of bovine and rat ribonucleases for different substrates. The most significant difference in the backbone conformation was observed in the loop 15-25. This loop incorporates the subtilisin cleavage site which is responsible for RNase A to RNase S conversion in the bovine enzyme. The rat enzyme does not get cleaved under identical conditions. Molecular docking of this region of the rat enzyme in the active site of subtilisin shows steric incompat- ibility, although the bovine pancreatic ribonuclease A appropriately fits into this active site. It is there- fore inferred that the local conformation of the substrate governs the specificity of subtilisin. Pro- teins 1999;35:1-12. r 1999 Wiley-Liss, Inc.
8 citations