Filamentation and inhibition of prokaryotic CTP synthase with ligands  

作　　者：Chenjun Guo Zixuan Wang Ji‐Long Liu 

机构地区：[1]School of Life Science and Technology,ShanghaiTech University,Shanghai,China [2]Department of Physiology,Anatomy and Genetics,University of Oxford,Oxford,UK [3]Shanghai Clinical Research and Trial Center,Shanghai,China

出　　处：《mLife》2024年第2期240-250,共11页微生物（英文）

基　　金：supported by the grants from the Ministry of Science and Technology of China(No.2021YFA0804700);National Natural Science Foundation of China(Grant Nos.32370744 and 32350710195);Shanghai Science and Technology Commission(No.20JC1410500);UK Medical Research Council(Grant Nos.MC_UU_12021/3 and MC_U137788471)for grants to J.L.L.

摘　　要：Cytidine triphosphate synthase(CTPS)plays a pivotal role in the de novo synthesis of cytidine triphosphate(CTP),a fundamental building block for RNA and DNA that is essential for life.CTPS is capable of directly binding to all four nucleotide triphosphates:adenine triphosphate,uridine triphosphate,CTP,and guanidine triphosphate.Furthermore,CTPS can form cytoophidia in vivo and metabolic filaments in vitro,undergoing regulation at multiple levels.CTPS is considered a potential therapeutic target for combating invasions or infections by viral or prokaryotic pathogens.Utilizing cryo-electron microscopy,we determined the structure of Escherichia coli CTPS(ecCTPS)filament in complex with CTP,nicotinamide adenine dinucleotide(NADH),and the covalent inhibitor 6-diazo-5-oxo-L-norleucine(DON),achieving a resolution of 2.9A.We constructed a phylogenetic tree based on differences in filament-forming interfaces and designed a variant to validate our hypothesis,providing an evolutionary perspective on CTPS filament formation.Our computational analysis revealed a solvent-accessible ammonia tunnel upon DON binding.Through comparative structural analysis,we discern a distinct mode of CTP binding of ecCTPS that differs from eukaryotic counterparts.Combining biochemical assays and structural analysis,we determined and validated the synergistic inhibitory effects of CTP with NADH or adenine on CTPS.Our results expand our comprehension of the diverse regulatory aspects of CTPS and lay a foundation for the design of specific inhibitors targeting prokaryotic CTPS.

关 键 词：CTP synthase Cryo-electron microscopy cytoophidium metabolic filament species specific inhibition 

分 类 号：Q55[生物学—生物化学]