Virtual screening is the name given to the process of docking three-dimensional models of drug-like compounds into three dimensional models of potential drug receptors, usually proteins. Such computational methods are far faster, and cheaper, than physically testing tens of thousands of potential drugs in chemical or cell-based assays, which has been a standard in the pharmaceutical industry for generations. The ligands to be docked may have a number of rotatable bonds, generating a huge number of potential conformations to be examined; energetic calculations are used to rank protein-ligand interactions. Today all large pharmaceutical houses use virtual screening operations to facilitate their drug discovery programs.
To support virtual screening, the Macromolecular Crystallography Facility houses the 64 core Drug Discovery Cluster and modern drug docking software including Gold, ICM, and Glide. The Drug Discovery Cluster contains 16 HP Proliant BL35P blade servers, each with 2 dual core AMD Opteron 2.4 GHz processors for a total of 64 processors. Each blade contains 8 GB of memory and a 6 GB ATA hard disk drive. The front-end of the cluster is an HP xw9300 Workstation, equipped with a dual core AMD Opteron 2.4 GHz processor, an NVIDIA Quadro FX4500 graphics card, 4 GB memory, and two 500 GB SATA hard drives. Also attached to the cluster is an HP Proliant DL380 G4 storage server with an Intel Xeon Processor (3.4 GHz) which supports a RAID5 network attached storage system with five 500 GB SATA disk drives.