Vol.:(0123456789) 1 3 Theoretical Chemistry Accounts (2019) 138:19 https://doi.org/10.1007/s00214-018-2404-z REGULAR ARTICLE Molecular mechanics of cafeic acid in food proflin allergens Haruna L. Barazorda‑Ccahuana 1  · Diego E. Valencia 1  · Badhin Gómez 1 Received: 17 May 2018 / Accepted: 17 December 2018 © Springer-Verlag GmbH Germany, part of Springer Nature 2019 Abstract Vegetable proflins are considered potent allergens for their cross-reactivity as a result of the high sequence identity. Nowa- days an attractive attention is focused to fnd new ligands to inhibit the active site of allergenic proflins. Some studies have shown that cafeic acid may have a certain inhibitory efect on some allergens. For this reason, we studied cafeic acid as an important ligand and its interaction between seven vegetable proflins. We applied molecular dynamic simulations methods and binding free energy analysis by MM–PBSA. We found that cafeic acid had a favorable behavior, and their coupling was mediated by hydrophobic interactions. Furthermore, the analysis of epitopes showed an important contribution of the secondary structure after docking simulations. Keywords Proflin · Allergy · Molecular mechanics · Cafeic acid 1 Introduction Allergies have been become a global health problem, with high prevalence rates that are increasing [1]. An important part of this disease group is food allergies, caused by intake of a specifc food containing proteins that our body recog- nizes as antigens [2]. Their severity is multifactorial and variable among people, and there are no specifc evalua- tions to determine the intensity of allergic reaction; never- theless, foods have key elements with high allergenic poten- tial, called allergens [3]. One of these allergens is proflin; they are proteins present in all living organism (including plants and animals) and have functions associated with actin polymerization in cellular cytoplasm. Vegetable proflins produce an activation of the immune system when they get into our organism; this reaction is part of type 1 hypersensitivity response. Not all proflins enter through food, and some do it by inhalation through the pollen of some plants. In 1992, birch pollen allergen was reported by Valenta et al. [4] as the frst allergenic proflin; less than 20 years had passed since the discovery of these proteins [5, 6]. The World Health Organization (WHO) and International Union of Immunological Societies (IUIS) have registered and recognized 48 proflins as allergens. Cross- reactions can occur among proflins from pollen and food (vegetables and/or fruits) because they have residue regions with high homology [7]. For this reason, they are also con- sidered pan-allergens. Structural alteration of proteins to modify their function is a methodology that has been used since the discovery of proteins [8]. Allergenic proflins also have been subjected to several processes to reduce their allergenic potential to alter their molecular structure, confguration, and proper- ties through physical–chemical treatments or adding com- pounds that reduce their allergenicity [9]. A thermal treat- ment process as high temperature in food processing can modify the native structure in diferent ways: denaturation, restructuring of the disulfde bonds, and generation of new bonds [10]. Structural changes can modify proflin epitopes, which directly interact with allergen receptors, altering their binding capacity to the antibody; nevertheless, this could generate the formation of new allergenic compounds [11]. Epitopes are identifed by the IgE; by changing the structural form between the proteins, these sites change, varying their epitopes, which can be altered by diferent reactions such Published as part of the special collection of articles “CHITEL 2017—Paris–France”. Electronic supplementary material The online version of this article (https://doi.org/10.1007/s00214-018-2404-z) contains supplementary material, which is available to authorized users. * Haruna L. Barazorda-Ccahuana hbarazorda@ucsm.edu.pe 1 Centro de Investigación en Ingeniería Molecular, Vicerrectorado de Investigación, Universidad Católica de Santa María, Urb. San José s/n, Umacollo, Arequipa, Peru