Synthesizing Amino Acids Modified with Reactive Carbonyls in Silico to Assess Structural Effects Using Molecular Dynamics Simulations 

Protein carbonylation by reactive aldehydes derived from lipid peroxidation leads to cross-linking, oligomerization, and aggregation of proteins, causing ...

University of Cartagena

The populations infected with malaria have developed genetic defense mechanisms in order to protect themselves against the most serious complications of this disease. Those mechanisms have been associated from the perspective of co-adaptive process with some genetic diseases widely present in humans as sickle-cell disease, sickle cell trait and glucose-6-phosphate dehydrogenase deficiency (G6PD). Biochemically, polymorphic mutations at the erythrocyte level have been widely studied, however there is no clear statement of the mechanisms used for resistance against the causative agent of malaria. The purpose of this review is to introduce the molecular and biochemical basis of defense mechanisms associated with two of those adaptations: sickle-cell trait and Glucose-6-phosphate Dehydrogenase Deficiency (G6PD). The first one is a hemoglobinopathy while the second one is the most frequent enzymopathy present in humans.

Human red blood cell polymorphisms prevalent in Colombian population and its protective role against malaria.

4-hydroxy-2-nonenal (4-HNE) is the main end product of peroxidation in lipids, capable of introduce carbonyl groups to nucleophilic amino acids via Michael additions and alter protein function. It has been reported that 4-HNE protein carbonylation is associated with intracellular protein aggregation, the pathogenesis of neurodegenerative and metabolic diseases and yet it is unclear how the carbonylation affects the protein structure and dynamics at the atomic level. Here, we analysis the structural effects of 4-HNE modification through formation of Michael adducts of Cys-4HNE, His-4HNE and Lys-4HNE on Serum Albumin (BSA) and Thioredoxin (TRX). Since both proteins have experimental evidence to possess 4-HNE-modifications on cysteine, histidine and lysine residues, extended molecular dynamics simulations were performed with AMBER to study the carbonylation effects in the structure of these proteins. BSA is the main protein of plasma while TRX is an important antioxidant enzyme. Results showed local changes and alteration in the conformational stability, folding and flexibility after including the 4-HNE modification. DSSP analysis showed important structural modifications as a consequence of the inclusion of the modified residues. Analysis of the computed trajectories suggests that 4-HNE decreases stability, increases local flexibility and produced modest unfolding on both tested proteins. Finally, all the systems evaluated shown an increase in the lipophilic potential and a modest decrease in the electrostatic potential in BSA but an increase in TRX.

4-HNE carbonylation induces local conformational changes on bovine serum albumin and thioredoxin. A molecular dynamics study.

The data described here support the research article "4-HNE carbonylation induces local conformational changes on bovine serum albumin and thioredoxin. A molecular dynamics study" (Alviz-Amador et al., 2018) . Dataset on Gaff force field parameters of AMBER is provided for assembled three non-standard amino acids resulting of the 4-HNE Michael addition, the main end product of lipids peroxidation. Data include a framework for derivation of missing bonds, angles and dihedral parameters for Cys, His, and Lys modified amino acids, alongside optimized partial charges derived with Restrained Electrostatic Potential (RESP) method and the new force field parameters obtained by quantic mechanical (QM) using HF/6-31G** level of theory. Benchmark as a graphics tutorial summary steps to obtained new parameters and the validation of non-standard amino acids is presented. The new residues constructed are put available to the scientific community to perform molecular dynamics simulations of modified 4-HNE proteins.

Development and benchmark to obtain AMBER parameters dataset for non-standard amino acids modified with 4-hydroxy-2-nonenal.

4-HNE-modified ankyrins have been described in diseases such as diabetes, renal failure, G6PD deficient, sickle cell trait,  infected erythrocytes with different AB0 blood groups. However, effects at the atomic level of this carbonylation on structure and function of modified protein are not yet fully understood. We present a study based on molecular dynamics simulations of nine 4-HNE modified residues of the ZU5-ANK ankyrin domain with β-spectrin and their binding energy profiles. Results show that 4-HNE induced local conformational changes over all protein systems evaluated, increased mobility in the modification sites, and localized structural changes between the positively charged patch of the ZU5-ANK domain. Carbonylation with 4-HNE on lysine residues decreased the affinity between ZU5-ANK and the 14-β-spectrin repeat by reducing electrostatic and van der Waals interactions. The presented work provides further insight into understanding the loss of human erythrocyte deformation capacity under conditions of oxidative stress in different diseases.

Effect of 4-HNE Modification on ZU5-ANK Domain and the Formation of Their Complex with β-Spectrin: A Molecular Dynamics Simulation Study.

The data described here supports a part of the research article "Effect of 4‑HNE Modification on ZU5-ANK Domain and the Formation of Their Complex with β‑Spectrin: A Molecular Dynamics Simulation Study" [1]. Dataset on Gaff force field parameters of AMBER is provided for the non-standard arginine resulting of reaction with 4-hydroxy-2-nonenal (4-HNE), the major secondary product of lipids peroxidation. Arg-HNE 2-pentilpyrrole adduct is part of the 4-hydroxyalkenals described in various physiopathological disorders related to increased oxidative stress. Data include a framework for derivation of missing bonds, angles and dihedral parameters for modified arginine, alongside optimized partial charges derived with Restrained Electrostatic Potential (RESP) method and the new force field parameters obtained by quantum mechanicals methods (QM) using Hartree-Fock (HF)/6 - 31G** level of theory. Benchmark as a graphics tutorial summary steps to obtained new parameters and the validation of non-standard amino acids is presented. The new residue constructed is put available to the scientific community to perform molecular dynamics simulations of modified 4-HNE proteins on arginine residue and complete the set of data parameters for nucleophilic residues with this reactive aldehyde ADDIN EN.CITE ADDIN EN.CITE.DATA [2]. Data that could be used for the researchers interested in the role of protein oxidation as mediator in cellular pathophysiological.

AMBER parameters and topology data of 2-pentylpyrrole adduct of arginine with 4-hydroxy-2-nonenal.

Leukoplakia is one of the most frequently found lesions in the oral cavity, with a probability of 17 to 24% of becoming malignant cells in a period of 30 years.

Bioinformatic Analysis of Plus Gene Expression Related to Progression from Leukoplakia to Oral Squamous Cell Carcinoma.

The emergence of the new SARS-CoV-2 virus, which causes the disease known as COVID-19, has generated a pandemic that has plunged the world into a health crisis. The infection process is triggered by the direct binding of the receptor-binding domain (RBD) of the spike (S) protein of SARS-CoV-2 to the angiotensin-converting enzyme 2 (ACE2) of the host cell. In the present study, virtual screening techniques such as molecular docking, molecular dynamics, calculation of free energy using the GBSA method, prediction of drug similarity, pharmacokinetic, and toxicological properties of various ligands interacting with the RBD-ACE2 complex were applied. The ligands radotinib, hinokiflavone, and ginkgetin were identified as potential destabilizers of the RBD-ACE2 interaction, which could produce their pharmacological effect by interacting at an allosteric site of ACE2, with affinity energy values of -10.2 ± 0.1, -9.8 ± 0.0, and -9.4 ± 0.0 kcal/mol, indicating strong receptor affinity. The complex with hinokiflavone showed the highest conformational stability and rigidity of the dynamic simulation and also obtained the best binding free energy of the three molecules, with an energy of -215.86 kcal/mol.

 study for the identification of potential destabilizers between the spike protein of SARS-CoV-2 and human ACE-2.

Protein oxidative modifications with reactive carbonyl species (RCS) is directly linked to metabolic processes in premature aging, cancer, neurodegenerative and infectious diseases. RCS as 4-Hydroxy-2-nonal (HNE), 4-Hydroxy-2-hexenal (HHE), 4-Oxo-2-nonenal (ONE) and Malondialdehyde (MDA) attack nucleophilic amino acids residues forming irreversible adducts with proteins as Thioredoxins (Trx). This is a class of small thiol oxide-reductases playing a key role in redox signaling and oxidative stress responses in mammals. Although proteomic studies have identified to Cys-32 residue as a target of HNE attack that inhibit its enzymatic activity, how this carbonylation affects its structure and dynamic behavior at the atomic level is unknown. Even more, the molecular bases for the atomistic behavior of these modified proteins have not been completely understood. We present molecular dynamics simulations of Trx-modified with four different RCS to analyze its global and local structural effects. For this, parameters supported in the AMBER force fields were built and validated for three non-natural cysteine residues modified with HHE, ONE and MDA. Results obtained showed a slight change in the global conformational stability of Trx modified with HNE and MDA, establishing that all modified proteins presented local regions of high mobility in the modified catalytic site and some regions far from the modification area. In addition, essential domain movement modes evidences that proteins modified with the RCS assayed induce changes in conformational flexibility. Finally, these data showed that the given conformational changes did not caused global changes in proteins but rather localized changes in particular regions.

Cysteine carbonylation with reactive carbonyl species from lipid peroxidation induce local structural changes on thioredoxin active site.

Serum albumin is the most abundant protein in the Mammalia blood plasma at where plays a decisive role in the transport wide variety of hydrophobic ligands. BSA undergoes oxidative modifications like the carbonylation by the reactive carbonyl species (RCSs) 4-hydroxy-2-nonenal (HNE), 4 hydroxy-2-hexenal (HHE), malondialdehyde (MDA) and 4-oxo-2-nonenal (ONE), among others. The structural and functional changes induced by protein carbonylation have been associated with the advancement of neurodegenerative, cardiovascular, metabolic and cancer diseases.

Antistio Alviz-Amador

Pharmacology and Therapeutics Research Group

University of Cartagena

Synthesizing Amino Acids Modified with Reactive Carbonyls in Silico to Assess Structural Effects Using Molecular Dynamics Simulations

Antistio Alviz-Amador

.css-o250i3{font-size:18px;font-family:Open Sans,sans-serif;line-height:21.6px;}Pharmacology and Therapeutics Research Group

University of Cartagena

Synthesizing Amino Acids Modified with Reactive Carbonyls in Silico to Assess Structural Effects Using Molecular Dynamics Simulations

Pharmacology and Therapeutics Research Group