VIEW ARTICLE    http://dx.doi.org/10.1094/ASBCJ-2012-0905-01

Combined Modeling and Biophysical Characterisation of CO(2) Interaction with Class II Hydrophobins: New Insight into the Mechanism Underpinning Primary Gushing. Sylvie M. Deckers (1), KU Leuven, Department of Microbial and Molecular Systems (M(^2)S), and Leuven Food Science and Nutrition Research Centre (LFoRCe), BE-3001 Heverlee, Belgium; Tom Venken (1), KU Leuven, Department of Chemistry, Division of Chemistry, section: Molecular and Structural Biology, Laboratory for Biomolecular Modelling and BioMacS, BE-3001 Heverlee, Belgium; Mohammadreza Khalesi (1) and Kurt Gebruers, KU Leuven, Department of Microbial and Molecular Systems (M(^2)S), and Leuven Food Science and Nutrition Research Centre (LFoRCe), BE-3001 Heverlee, Belgium; Geert Baggerman, KU Leuven, Facility for Systems Biology based Mass Spectrometry (SyBioMa), BE-3000 Leuven, Belgium; Yannick Lorgouilloux, KU Leuven, Department of Microbial and Molecular Systems (M(^2)S), Centre for Surface Chemistry and Catalysis, BE-3001 Heverlee, Belgium; Zahra Shokribousjein, KU Leuven, Department of Microbial and Molecular Systems (M(^2)S), and Leuven Food Science and Nutrition Research Centre (LFoRCe), BE-3001 Heverlee, Belgium; Vladimir Ilberg, Hochschule Weihenstephan-Triesdorf, Fakultät Gartenbau und Lebensmitteltechnologie, D-85350 Freisinig, Germany; Christina Schönberger, Barth-Haas Group, Barth Innovations, D-90482 Nuremberg, Germany; Jean Titze, National University of Ireland, University College Cork, School of Food and Nutritional Sciences, Cork, Ireland; Hubert Verachtert and Chris Michiels, KU Leuven, Department of Microbial and Molecular Systems (M(^2)S), and Leuven Food Science and Nutrition Research Centre (LFoRCe), BE-3001 Heverlee, Belgium; Hedwig Neven, KU Leuven, Department of Microbial and Molecular Systems (M(^2)S), and Leuven Food Science and Nutrition Research Centre (LFoRCe), BE-3001 Heverlee, Belgium and Brewery Duvel-Moortgat, BE-2870 Puurs, Belgium; Jan Delcour, KU Leuven, Department of Microbial and Molecular Systems (M(^2)S), and Leuven Food Science and Nutrition Research Centre (LFoRCe), BE-3001 Heverlee, Belgium; Johan Martens, KU Leuven, Department of Microbial and Molecular Systems (M(^2)S), Centre for Surface Chemistry and Catalysis, BE-3001 Heverlee, Belgium; Guy Derdelinckx (1,2), KU Leuven, Department of Microbial and Molecular Systems (M(^2)S), and Leuven Food Science and Nutrition Research Centre (LFoRCe), BE-3001 Heverlee, Belgium; and Marc De Maeyer (1,3), KU Leuven, Department of Chemistry, Division of Chemistry, section: Molecular and Structural Biology, Laboratory for Biomolecular Modelling and BioMacS, BE-3001 Heverlee, Belgium. (1) These authors contributed equally to the work. (2) Corresponding author. E-mail: <Guy.Derdelinckx@biw.kuleuven.be>, phone: +32-16-321461, fax: +32-16-321997. (3) Corresponding author. E-mail: <Marc.DeMaeyer@fys.kuleuven.be>, phone: +32-16-327521, fax: +32-16-327974 J. Am. Soc. Brew. Chem. 70(4):249-256, 2012.

Although there is a common agreement that hydrophobins and CO(2) are responsible for primary gushing of carbonated beverages, the bio-molecular mechanism of this phenomenon is not well understood. Here, hydrophobin HFBII has been produced, extracted, and purified. A gushing test and DLS analysis was performed and allowed the authors to design an MD simulation setup to investigate the interaction of CO(2) molecules with HFBII in time. The results indicate that CO(2) molecules tend to aggregate at the hydrophobic patch of HFBII twice as much as to the rest of the protein. A model is proposed that elucidates the “nanobomb” formation depicting a definite chemical and biophysical description of the primary gushing mechanism. Keywords: CO(2), Gushing, Hydrophobin, MD simulation, Nanobubble

Aunque no existe un acuerdo común que hidrofobinas y CO(2) son responsables de chorro primario de las bebidas carbonatadas, el mecanismo de bio-molecular de este fenómeno no se entiende bien. Aquí, hidrofobina HFBII se fue producido, se extrae y purifica. Una prueba de gushing y el análisis de DLS se realizó y permitió a los autores para diseñar una configuración de simulación MD para investigar la interacción de moléculas de CO(2) con HFBII en el tiempo. Los resultados indican que las moléculas de CO(2) tiende a agregarse en el parche hidrófobo de HFBII dos veces más que para el resto de la proteína. Se propone un modelo que aclara el “nanobomb” formación que representa una descripción definida químicos y biofísicos del mecanismo de gushing principal. Palabras claves: CO(2), gushing, hidrofobina, simulación MD, Nanobubble