RT Journal Article
SR Electronic
T1 Inhibition and Crystal Structure of the Human DHTKD1-Thiamin Diphosphate Complex
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2020.01.20.913012
DO 10.1101/2020.01.20.913012
A1 João Leandro
A1 Susmita Khamrui
A1 Hui Wang
A1 Chalada Suebsuwong
A1 Natalia S. Nemeria
A1 Khoi Huynh
A1 Moses Moustakim
A1 Cody Secor
A1 May Wang
A1 Tetyana Dodatko
A1 Brandon Stauffer
A1 Christopher G. Wilson
A1 Chunli Yu
A1 Michelle R. Arkin
A1 Frank Jordan
A1 Roberto Sanchez
A1 Robert J. DeVita
A1 Michael B. Lazarus
A1 Sander M. Houten
YR 2020
UL http://biorxiv.org/content/early/2020/01/21/2020.01.20.913012.abstract
AB DHTKD1 is the E1 component of the 2-oxoadipic acid dehydrogenase complex (OADHc), which functions in the L-lysine degradation pathway. Mutations in DHTKD1 have been associated with 2-aminoadipic and 2-oxoadipic aciduria, Charcot-Marie-Tooth disease type 2Q (CMT2Q) and eosinophilic esophagitis (EoE). A crystal structure and inhibitors of DHTKD1 could improve the understanding of these clinically distinct disorders, but are currently not available. Here we report the identification of adipoylphosphonic acid and tenatoprazole as DHTKD1 inhibitors using targeted and high throughput screening, respectively. We furthermore elucidate the DHTKD1 crystal structure with thiamin diphosphate bound at 2.1 Å. The protein assembles as a dimer with residues from both monomers contributing to cofactor binding. We also report the impact of ten DHTKD1 missense mutations on the encoded proteins by enzyme kinetics, thermal stability and structural modeling. Some DHTKD1 variants displayed impaired folding (S777P and S862I), whereas other substitutions rendered the enzyme inactive (L234G, R715C and R455Q) or affected the thermal stability and catalytic efficiency (V360A and P773L). Three variants (R163Q, Q305H and G729R) surprisingly showed wild type like properties. Our work provides a structural basis for further understanding of the function of DHTKD1 and a starting point for selective small molecule inhibitors of the enzyme, which could help tease apart the role of this enzyme in several human pathologies.