4ZQ0

crystal structure of Giardia 14-3-3 in complex with the phosphopeptide A8Ap

Summary for 4ZQ0

• Entry DOI: 10.2210/pdb4zq0/pdb
• Descriptor: 14-3-3 protein, A8Ap phosphopeptide, PHOSPHATE ION (3 entities in total)
• Functional Keywords: phosphopeptide binding protein-protein interaction, signaling protein
• Biological source: Giardia lamblia P15; More
• Total number of polymer chains: 8
• Total formula weight: 112041.38

Authors

Fiorillo, A.,Ilari, A. (deposition date: 2015-05-08, release date: 2016-03-30, Last modification date: 2024-10-16)

Primary citation

Cau, Y.,Fiorillo, A.,Mori, M.,Ilari, A.,Botta, M.,Lalle, M.
Molecular Dynamics Simulations and Structural Analysis of Giardia duodenalis 14-3-3 Protein-Protein Interactions.
J.Chem.Inf.Model., 55:2611-2622, 2015

PubMed Abstract: Giardiasis is a gastrointestinal diarrheal illness caused by the protozoan parasite Giardia duodenalis, which affects annually over 200 million people worldwide. The limited antigiardial drug arsenal and the emergence of clinical cases refractory to standard treatments dictate the need for new chemotherapeutics. The 14-3-3 family of regulatory proteins, extensively involved in protein-protein interactions (PPIs) with pSer/pThr clients, represents a highly promising target. Despite homology with human counterparts, the single 14-3-3 of G. duodenalis (g14-3-3) is characterized by a constitutive phosphorylation in a region critical for target binding, thus affecting the function and the conformation of g14-3-3/clients interaction. However, to approach the design of specific small molecule modulators of g14-3-3 PPIs, structural elucidations are required. Here, we present a detailed computational and crystallographic study exploring the implications of g14-3-3 phosphorylation on protein structure and target binding. Self-Guided Langevin Dynamics and classical molecular dynamics simulations show that phosphorylation affects locally and globally g14-3-3 conformation, inducing a structural rearrangement more suitable for target binding. Profitable features for g14-3-3/clients interaction were highlighted using a hydrophobicity-based descriptor to characterize g14-3-3 client peptides. Finally, the X-ray structure of g14-3-3 in complex with a mode-1 prototype phosphopeptide was solved and combined with structure-based simulations to identify molecular features relevant for clients binding to g14-3-3. The data presented herein provide a further and structural understanding of g14-3-3 features and set the basis for drug design studies.

PubMed: 26551337
DOI: 10.1021/acs.jcim.5b00452

Experimental method

X-RAY DIFFRACTION (3.1 Å)