title: Heterodimerization of the Entamoeba histolytica EhCPADH virulence complex through molecular dynamics and protein-protein docking.
abstract: EhCPADH is a protein complex involved in the virulence of Entamoeba histolytica, the protozoan responsible for human amebiasis. It is formed by the EhCP112 cysteine protease and the EhADH adhesin. To explore the molecular basis of the complex formation, three-dimensional models were built for both proteins and molecular dynamics simulations (MDS) and docking calculations were performed. Results predicted that the pEhCP112 proenzyme and the mEhCP112 mature enzyme were globular and peripheral membrane proteins. Interestingly, in pEhCP112, the propeptide appeared hiding the catalytic site (C167, H329, N348); while in mEhCP112, this site was exposed and its residues were found structurally closer than in pEhCP112. EhADH emerged as an extended peripheral membrane protein with high fluctuation in Bro1 and V shape domains. 500 ns-long MDS and protein-protein docking predictions evidenced different heterodimeric complexes with the lowest free energy. pEhCP112 interacted with EhADH by the propeptide and C-terminal regions and mEhCP112 by the C-terminal through hydrogen bonds. In contrast, EhADH bound to mEhCP112 by 442-479 residues, adjacent to the target cell-adherence region (480-600 residues), and by the Bro1 domain (9-349 residues). Calculations of the effective binding free energy and per residue free energy decomposition showed that EhADH binds to mEhCP112 with a higher binding energy than to pEhCP112, mainly through van der Waals interactions and the nonpolar part of solvation energy. The EhADH and EhCP112 structural relationship was validated in trophozoites by immunofluorescence, TEM, and immunoprecipitation assays. Experimental findings fair agreed with in silico results.
authors: a Departamento de Infectómica y Patogénesis Molecular , Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN) , Ave. IPN 2508, San Pedro Zacatenco, México, D.F. 07360 , Mexico.
authors: Sarita
authors: S
authors: Montaño
authors: a Departamento de Infectómica y Patogénesis Molecular , Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN) , Ave. IPN 2508, San Pedro Zacatenco, México, D.F. 07360 , Mexico.
authors: Esther
authors: E
authors: Orozco
authors: b Laboratorio de Modelado Molecular, Bioinformática y Diseño de Fármacos , Escuela Superior de Medicina del Instituto Politécnico Nacional (ESM-IPN) , Plan de San Luis y Díaz Mirón s/n, Miguel Hidalgo, Casco de Santo Tomas, México, D.F. 11340 , Mexico.
authors: José
authors: J
authors: Correa-Basurto
authors: b Laboratorio de Modelado Molecular, Bioinformática y Diseño de Fármacos , Escuela Superior de Medicina del Instituto Politécnico Nacional (ESM-IPN) , Plan de San Luis y Díaz Mirón s/n, Miguel Hidalgo, Casco de Santo Tomas, México, D.F. 11340 , Mexico.
authors: Martiniano
authors: M
authors: Bello
authors: a Departamento de Infectómica y Patogénesis Molecular , Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN) , Ave. IPN 2508, San Pedro Zacatenco, México, D.F. 07360 , Mexico.
authors: Bibiana
authors: B
authors: Chávez-Munguía
authors: a Departamento de Infectómica y Patogénesis Molecular , Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN) , Ave. IPN 2508, San Pedro Zacatenco, México, D.F. 07360 , Mexico.
authors: Abigail
authors: A
authors: Betanzos
mesh_terms: D000426:Alcohol Dehydrogenase / Q000737:chemistry*; D004748:Entamoeba histolytica / Q000201:enzymology*; D006801:Humans; D008565:Membrane Proteins / Q000737:chemistry; D062105:Molecular Docking Simulation; D056004:Molecular Dynamics Simulation; D011485:Protein Binding; D011487:Protein Conformation; D054730:Protein Interaction Domains and Motifs; D055503:Protein Multimerization; D015800:Protozoan Proteins / Q000737:chemistry*
chemical_list: D008565:Membrane Proteins; D015800:Protozoan Proteins; D000426:Alcohol Dehydrogenase
keywords: ALIX family proteins; EhADH; Entamoeba histolytica; cysteine proteases; molecular dynamics simulation; protein–protein docking