In cellulo crystallization of Trypanosoma brucei IMP dehydrogenase enables the identification of genuine co-factors

• DOI: 10.1038/s41467-020-14484-w
• Publication Date: 2020-01-30T11:02:57Z
• Authors: Karol Nass; Lars Redecke; M. Perbandt; O. Yefanov; M. Klinge; R. Koopmann; F. Stellato; A. Gabdulkhakov; R. Schönherr; D. Rehders; J. M. Lahey-Rudolph; A. Aquila; A. Barty; S. Basu; R. B. Doak; R. Duden; M. Frank; R. Fromme; S. Kassemeyer; G. Katona; R. Kirian; H. Liu; I. Majoul; J. M. Martin-Garcia; M. Messerschmidt; R. L. Shoeman; U. Weierstall; S. Westenhoff; T. A. White; G. J. Williams; C. H. Yoon; N. Zatsepin; P. Fromme; M. Duszenko; H. N. Chapman; C. Betzel
• Keywords: Inosine

Abstract Sleeping sickness is a fatal disease caused by the protozoan parasite Trypanosoma brucei (Tb). Inosine-5’-monophosphate dehydrogenase (IMPDH) has been proposed as potential drug target, since it maintains balance between guanylate deoxynucleotide and ribonucleotide levels that pivotal for parasite. Here we report structure of TbIMPDH at room temperature utilizing free-electron laser radiation on crystals grown in living insect cells. The 2.80 Å resolution reveals presence ATP GMP canonical sites Bateman domains, latter so far unknown coordination mode. Consistent with previously reported IMPDH complexes harboring guanosine nucleotides second site, forms compact oligomer structure, supporting nucleotide-controlled conformational switch allosterically modulates catalytic activity. oligomeric present here cellulo crystallization to identify genuine allosteric co-factors from natural reservoir specific compounds.