Antibodies against a peptide of cholera toxin differing in cross-reactivity with the toxin differ in their specific interactions with the peptide as observed by sup 1 H NMR spectroscopy

Journal Article · Tue Jan 30 00:00:00 EST 1990 · Biochemistry; (USA)

DOI:https://doi.org/10.1021/bi00456a011· OSTI ID:6717679

Anglister, J; Zilber, B ^[1]

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1. Weizmann Institute of Science, Rehovot (Israel)

The interactions between the aromatic residues of the monoclonal antibody TE34, and its peptide antigen CTP3, have been studied by 2D TRNOE difference spectroscopy. The sequence of CTP3 corresponds to residues 50-64 of the B subunit of cholera toxin (VEVPGSQHIDSQKKA). Unlike two previously studied anti-CTP3 antibodies (TE32 and TE33), the TE34 antibody does not bind the toxin. The off-rate of CTP3 from TE34 was found to be too slow to measure strong TRNOE cross-peaks between the antibody and the peptide. Much faster off-rates, resulting in a strong TRNOE, were obtained for two peptide analogues: (a) CTP3 with an amide in the C-terminus (VEVPGSQHIDSQKKA-NH{sub 2}) and (b) a truncated version of the peptide (N-acetyl-IDSQKKA). These modifications do not interfere significantly either with the interactions of the unmodified part of the peptide with the antibody or with intramolecular interactions occurring in the epitope recognized by the antibody. The combined use of these peptides allows us to study the interactions between the antibody and the whole peptide. Two tyrosine residues and one or more tryptophan and phenylalanine residues have been found to interact with histidine-8, isoleucine-9, aspartate-10, lysine-13 and/or lysine-14, and alanine-15 of the peptide. The strong interaction of TE34 with the negatively charged C-terminus of CTP3 is one of the main reasons for its lack of cross-reactivity with the native toxin. Similar use of modified peptides may extend the applicability of 2D TRNOE difference spectroscopy to the study of other antibody-peptide complexes involving slow peptide off-rates.

• OSTI ID: 6717679
• Journal Information: Biochemistry; (USA), Vol. 29:4; ISSN 0006-2960
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
PEPTIDES
MONOCLONAL ANTIBODIES
TOXINS
NUCLEAR MAGNETIC RESONANCE
CHEMICAL SHIFT
CHOLERA
NMR SPECTRA
OVERHAUSER EFFECT
PROTONS
RESONANCE FLUORESCENCE
ANTIBODIES
ANTIGENS
BACTERIAL DISEASES
BARYONS
DISEASES
ELEMENTARY PARTICLES
FERMIONS
FLUORESCENCE
HADRONS
INFECTIOUS DISEASES
LUMINESCENCE
MAGNETIC RESONANCE
MATERIALS
NUCLEONS
ORGANIC COMPOUNDS
PROTEINS
RESONANCE
SPECTRA
TOXIC MATERIALS
550601* - Medicine- Unsealed Radionuclides in Diagnostics