The low-density lipoprotein receptor: three-dimensional structure and analysis of its interaction with minor receptor group human rhinovirus

Every viral infection is initiated by the attachment of the virus to the cell surface. Thereby, the presence or absence of a given `viral receptor` decides on whether an infection ensues. Human rhinoviruses, the causative agents of the common cold, exist in form of a great number of variants; they can be divided into two groups according to the receptor they use for cell entry. There is a large group with 91 serotypes, which all bind to intercellular adhesion molecule 1 and a small group with 10 serotypes, which bind to members of the low-density lipoprotein receptors (LDL-receptors). These proteins are responsible for the clearance of cholesterol from the blood stream amongst many other functions. Within the frame of the project fragments of members of this receptor family were produced in bacteria in a soluble form (i.e. not associated with the membrane as they exist in nature) and their association with the virus was investigated. Thereby we discovered that the binding site was totally different from that recognised by the intercellular adhesion molecule. Small fragments of the receptor are able to prevent the virus infection in tissue culture. By targeted modification of these receptor fragments towards an increase in binding strength it might be possible to combat at least the small group of these viruses.