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7sb7

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Crystal structure of T. brucei hypoxanthine guanine phosphoribosyltransferase in complex with (4S,7S)-7-hydroxy-4-((guanin-9-yl)methyl)-2,5-dioxaheptan-1,7-diphosphonate

Structural highlights

7sb7 is a 2 chain structure with sequence from Trypanosoma brucei brucei. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	X-ray diffraction, Resolution 2.6471663Å
Ligands:
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

HPRT_TRYBB Converts guanine to guanosine monophosphate, and hypoxanthine to inosine monophosphate. Transfers the 5-phosphoribosyl group from 5-phosphoribosylpyrophosphate onto the purine. Plays a central role in the generation of purine nucleotides through the purine salvage pathway (By similarity).

Publication Abstract from PubMed

Pathogens such as Plasmodium and Trypanosoma spp. are unable to synthesize purine nucleobases. They rely on the salvage of these purines and their nucleosides from the host cell to synthesize the purine nucleotides required for DNA/RNA production. The key enzymes in this pathway are purine phosphoribosyltransferases (PRTs). Here, we synthesized 16 novel acyclic nucleoside phosphonates, 12 with a chiral center at C-2', and eight bearing a second chiral center at C-6'. Of these, bisphosphonate (S,S)-48 is the most potent inhibitor of the Plasmodium falciparum and P. vivax 6-oxopurine PRTs and the most potent inhibitor of two Trypanosoma brucei (Tbr) 6-oxopurine PRTs yet discovered, with Ki values as low as 2 nM. Crystal structures of (S,S)-48 in complex with human and Tbr 6-oxopurine PRTs show that the inhibitor binds to the enzymes in different conformations, providing an explanation for its potency and selectivity (i.e., 35-fold in favor of the parasite enzymes).

Stereo-Defined Acyclic Nucleoside Phosphonates are Selective and Potent Inhibitors of Parasite 6-Oxopurine Phosphoribosyltransferases.,Klejch T, Keough DT, King G, Dolezelova E, Cesnek M, Budesinsky M, Zikova A, Janeba Z, Guddat LW, Hockova D J Med Chem. 2022 Feb 17. doi: 10.1021/acs.jmedchem.1c01881. PMID:35175749^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Klejch T, Keough DT, King G, Dolezelova E, Cesnek M, Budesinsky M, Zikova A, Janeba Z, Guddat LW, Hockova D. Stereo-Defined Acyclic Nucleoside Phosphonates are Selective and Potent Inhibitors of Parasite 6-Oxopurine Phosphoribosyltransferases. J Med Chem. 2022 Feb 17. doi: 10.1021/acs.jmedchem.1c01881. PMID:35175749 doi:http://dx.doi.org/10.1021/acs.jmedchem.1c01881