Protein Crystal Screening Service

Protein Crystal Screening Fee Structure

Brief description of the screening service

The need for crystal and screening: X-rays interact with proteins and macromolecules in general weakly and therefore diffraction from a single protein molecule will be difficult detect. However, a three dimensional crystal with tens of thousands of ordered protein molecules will enhance the signal many times thereby making it possible to record diffraction pattern. Despite the enormous progress structural biologists have made in solving protein structures, obtaining protein crystal is still hard and knowing a priori the condition in which a protein will crystallize is still not easy. That is why we need to screen several conditions to find one that will work.

The new service: In order to expand the Institute of Molecular Biophysics (IMB) X-Ray Facility’s user-base to non-traditional users of the Facility and to seek out general interest for a future acquisition of an automated crystal screening service, IMB XRF is proposing a new protein crystal screening service (PCSS). This service will be open to current and new users and the fee structure will be based on recouping base cost of the materials. PCSS will essentially be a manual set-up of one batch of 96 individual crystallization screen conditions (selected either by the user or the Facility) for a target protein at room temperature. The screens will then be visually inspected at pre-set times, scored and the results summarized for the user. Optionally, the user can request a Pre-Crystallization Test (PCT) be performed before beginning screening service to determine whether concentration of the protein being provided for screening is at optimal concentration required for screening.

Preliminary data: Based on the screen results, the user can then select to further optimize the conditions for growing a crystal at the Facility or in his/her own lab. The user can also select to collect preliminary data at the Facility or another location. The preliminary data will tell the user the crystal’s space group, solvent content, and number of molecules in the unit cell essential parameters in solving of the crystal structure.

Advantage of 3-d structure: A functional protein’s 3d structure will show how its active site or binding site will interact with the substrate(s). A structural protein’s 3d structure can show how it interacts with other components. High resolution 3d structure of enzyme can show hydrogen bonding interactions with substrates that can lead the mechanism of action. Even though complete structure solution for a protein is not yet envisioned to be part of this service, but could be considered at a later time. The user fees will be based on what all services are requested (screening-only, crystal optimization, preliminary data collection, etc.).

Detailed Information: For more detailed information go to Full-XRF-PCSS.