The X-ray structure of a ternary complex between human chorionic gonadotropin hormone (hCG) and two Fvs recognizing its α and β subunits has been recently determined. The Fvs recognize the elongated hCG molecule by its two ends, one being the Leu-12–Cys-29 loop of the α subunit. We have designed and synthesized a 17-amino-acid peptide (named PepH14) derived from the sequence of this antigenic loop with the purpose of mimicking its three-dimensional structure and its affinity for antibodies. We have determined the solution structure of PepH14 by homonuclear NMR spectroscopy and derived distance restraints. Comparison of this structure with that of the corresponding antigenic loop of α-hCG reveals strong conformational similarities. In particular, the two pairs of residues that establish crucial contacts with the Fv fragment share the same conformation in PepH14 and in the authentic hormone loop. We propose a three-dimensional model of interaction of PepH14 with a llama VHH (VHH-H14) fragment cloned from a single-chain llama immunoglobulin raised against α-hCG. This model has been constrained by the chemical shift variations of the H14 1HN and 15N resonances monitored upon binding with PepH14. Mapping of the backbone chemical shift variations on the VHH structure determined by NMR indicates that PepH14 binds to VHH-H14 and forms a complex using the three complementary determining regions (CDRs). They define a shallow groove encompassing residues Thr-31, Ala-56, Tyr-59 and Trp-104 which have been shown to be in conformational exchange [Renisio, Pérez, Czisch, Guenneugues, Bornet, Frenken, Cambillau and Darbon (2002) Proteins 47, 546–555] and also Phe-37 and Ala-50. This groove is close to the hydrophobic interface area observed between VH and VL domains in Fvs from classical antibodies, which explains the rather lateral binding of PepH14 on the VHH.
Skip Nav Destination
Article navigation
September 2002
- PDF Icon PDF LinkFront Matter
Research Article|
September 01 2002
A peptide mimic of an antigenic loop of α-human chorionic gonadotropin hormone: solution structure and interaction with a llama VHH domain
Gilles FERRAT;
Gilles FERRAT
1
∗Architecture et Fonction des Macromolécules Biologiques, UMR 6098, CNRS and Universités d'Aix-Marseille I and II, 31 Chemin Joseph Aiguier, 13402 Marseille, CEDEX 20, France
Search for other works by this author on:
Jean-Guillaume RENISIO;
Jean-Guillaume RENISIO
1
∗Architecture et Fonction des Macromolécules Biologiques, UMR 6098, CNRS and Universités d'Aix-Marseille I and II, 31 Chemin Joseph Aiguier, 13402 Marseille, CEDEX 20, France
Search for other works by this author on:
Xavier MORELLI;
Xavier MORELLI
2
†Division of Hemostasis and Thrombosis Research, Beth Israel Deaconess Medical Centre, Harvard Medical School, Boston, MA 02115, U.S.A.,
Search for other works by this author on:
Jerry SLOOTSTRA;
Jerry SLOOTSTRA
‡Department of Molecular Recognition, Institute for Animal Health and Science (ID-Lelystad), Edelhertweg 15, 8219 PH Lelystad, The Netherlands
Search for other works by this author on:
Rob MELOEN;
Rob MELOEN
‡Department of Molecular Recognition, Institute for Animal Health and Science (ID-Lelystad), Edelhertweg 15, 8219 PH Lelystad, The Netherlands
Search for other works by this author on:
Christian CAMBILLAU;
Christian CAMBILLAU
3
∗Architecture et Fonction des Macromolécules Biologiques, UMR 6098, CNRS and Universités d'Aix-Marseille I and II, 31 Chemin Joseph Aiguier, 13402 Marseille, CEDEX 20, France
3Correspondence may be addressed to either author (e-mail herve@afmb.cnrs-mrs.fr or cambillau@afmb.cnrs-mrs.fr).
Search for other works by this author on:
Hervé DARBON
Hervé DARBON
3
∗Architecture et Fonction des Macromolécules Biologiques, UMR 6098, CNRS and Universités d'Aix-Marseille I and II, 31 Chemin Joseph Aiguier, 13402 Marseille, CEDEX 20, France
3Correspondence may be addressed to either author (e-mail herve@afmb.cnrs-mrs.fr or cambillau@afmb.cnrs-mrs.fr).
Search for other works by this author on:
Publisher: Portland Press Ltd
Received:
January 29 2002
Revision Received:
April 23 2002
Accepted:
May 07 2002
Accepted Manuscript online:
May 07 2002
Online ISSN: 1470-8728
Print ISSN: 0264-6021
The Biochemical Society, London ©2002
2002
Biochem J (2002) 366 (2): 415–422.
Article history
Received:
January 29 2002
Revision Received:
April 23 2002
Accepted:
May 07 2002
Accepted Manuscript online:
May 07 2002
Citation
Gilles FERRAT, Jean-Guillaume RENISIO, Xavier MORELLI, Jerry SLOOTSTRA, Rob MELOEN, Christian CAMBILLAU, Hervé DARBON; A peptide mimic of an antigenic loop of α-human chorionic gonadotropin hormone: solution structure and interaction with a llama VHH domain. Biochem J 1 September 2002; 366 (2): 415–422. doi: https://doi.org/10.1042/bj20020172
Download citation file:
Sign in
Don't already have an account? Register
Sign in to your personal account
You could not be signed in. Please check your email address / username and password and try again.
Captcha Validation Error. Please try again.