SUMMARY This administrative supplement for equipment is requesting funds to purchase a Beckman Coulter Avanti® JXN- 26 IVD high-speed centrifuge with rotors and accessories, which is essential for the preparation of large quantities of crystalline pure protein required for 3D structure analysis work, and for the biochemical and functional characterization of both wild-type and mutant proteins. The requested equipment is critical for the successful completion of the specific aims of the parent project and within the original project scope. The new Avanti centrifuge will replace our inoperable Sorvall centrifuge that was used to generate the preliminary data presented in the funded parent award, but which unexpectedly failed and can no longer be repaired due to lack of replacement parts. The new high-performance centrifuge will ensure that the goals of the funded parent project will be met and that rapid progress is continuously made. In addition to the PI (Tsai), who will be the major user of the new centrifuge, the equipment is available to his co-investigators (Lee and Catic), who do not possess a high-performance centrifuge and currently lack the capability to process large volumes of cell culture. The requested equipment will be housed in dedicated space within the Tsai laboratory and will be managed by members of the Tsai group. To maintain the Avanti centrifuge in peak condition, the Department of Biochemistry at Baylor College of Medicine is committed to cover the annual maintenance of the new centrifuge after the one-year installation warranty has expired.