An NMR‐based identification of peptide fragments mimicking the interactions of the cathepsin B propeptide

FEBS Letters

Magny, Marie-Claude¹  Yu, Youlu³  Dupras, Robert²  Ni, Feng³  de Miguel, Elisa¹  Goudreau, Nathalie³  Vranken, Wim³  Mort, John S³  Storer, Andrew C³ 

[1] Joint Diseases Laboratory, Shriners Hospital for Children and Department of Surgery, McGill University, Montreal, Que. H3G 1A6, Canada;Enzyme Engineering Laboratories, Biotechnology Research Institute, National Research Council of Canada, 6100 Royalmount Avenue, Montreal, Que. H4P 2R2, Canada;Protein Engineering Network of Centres of Excellence, Montreal, Que. H4P 2R2, Canada

关键词: Protein-protein interaction;    Peptide design;    Nuclear magnetic resonance;    Cysteine protease;   

DOI  :  10.1016/S0014-5793(98)00548-1

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Selected fragments of the 62-residue proregion (or residues 1p–62p) of the cysteine protease cathepsin B were synthesized and their interactions with cathepsin B studied by use of proton NMR spectroscopy. Peptide fragments 16p–51p and 26p–51p exhibited differential perturbations of their proton resonances in the presence of cathepsin B. These resonance perturbations were lost for the further truncated 36p–51p fragment, but remained in the 26p–43p and 28p–43p peptide fragments. Residues 23p–26p or TWQ²⁵A in the N-terminal 1p–29p fragment did not show cathepsin B-induced resonance perturbations although the same residues had strongly perturbed proton resonances within the 16p–51p peptide. Both the 1p–29p and 36p–51p fragments lack a common set of hydrophobic residues 30p–35p or F³⁰YNVDI³⁵ from the proregion. The presence of residues F³⁰YNVDI³⁵ appears to confer a conformational preference in peptide fragments 16p–51p, 26p–51p, 28p–43p and 26p–43p, but the same residues induce the aggregation of peptides 16p–36p and 1p–36p. The peptide fragment 26p–43p binds to the active site, as indicated by its inhibition of the catalytic activity of cathepsin B. The cathepsin B prosegment can therefore be reduced into smaller, but functional subunits 28p–43p or 26p–43p that retain specific binding interactions with cathepsin B. These results also suggest that residues F³⁰YNVDI³⁵ may constitute an essential element for the selective inhibition of cathepsin B by the full-length cathepsin B proregion.

【 授权许可】

Unknown