Regular Article

The European Physical Journal E

, 36:62

Protein packing defects “heat up” interfacial water

  • María Belén SierraAffiliated withSección Fisicoquímica, INQUISUR-UNS-CONICET-Departamento de Química, Universidad Nacional del Sur
  • , Sebastián R. AccordinoAffiliated withSección Fisicoquímica, INQUISUR-UNS-CONICET-Departamento de Química, Universidad Nacional del Sur
  • , J. Ariel Rodriguez-FrisAffiliated withSección Fisicoquímica, INQUISUR-UNS-CONICET-Departamento de Química, Universidad Nacional del Sur
  • , Marcela A. MoriniAffiliated withSección Fisicoquímica, INQUISUR-UNS-CONICET-Departamento de Química, Universidad Nacional del Sur
  • , Gustavo A. AppignanesiAffiliated withSección Fisicoquímica, INQUISUR-UNS-CONICET-Departamento de Química, Universidad Nacional del Sur
  • , Ariel Fernández StiglianoAffiliated withInstituto Argentino de Matemática “Alberto P. Calderón”, CONICET (National Research Council)Collegium Basilea, Institute for Advanced Study

Rent the article at a discount

Rent now

* Final gross prices may vary according to local VAT.

Get Access

Abstract

Ligands must displace water molecules from their corresponding protein surface binding site during association. Thus, protein binding sites are expected to be surrounded by non-tightly-bound, easily removable water molecules. In turn, the existence of packing defects at protein binding sites has been also established. At such structural motifs, named dehydrons, the protein backbone is exposed to the solvent since the intramolecular interactions are incompletely wrapped by non-polar groups. Hence, dehydrons are sticky since they depend on additional intermolecular wrapping in order to properly protect the structure from water attack. Thus, a picture of protein binding is emerging wherein binding sites should be both dehydrons rich and surrounded by easily removable water. In this work we shall indeed confirm such a link between structure and dynamics by showing the existence of a firm correlation between the degree of underwrapping of the protein chain and the mobility of the corresponding hydration water molecules. In other words, we shall show that protein packing defects promote their local dehydration, thus producing a region of “hot” interfacial water which might be easily removed by a ligand upon association.

Graphical abstract

http://static-content.springer.com/image/art%3A10.1140%2Fepje%2Fi2013-13062-7/MediaObjects/10189_2013_9876_Figa_HTML.gif

Keywords

Soft Matter: Interfacial Phenomena and Nanostructured Surfaces