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The Leishmania donovani UMP synthase is essential for promastigote viability and has an unusual tetrameric structure that exhibits substrate-controlled oligomerization.
J Biol Chem. 2011 Jun 10; 286(23):20930-41.JB

Abstract

The final two steps of de novo uridine 5'-monophosphate (UMP) biosynthesis are catalyzed by orotate phosphoribosyltransferase (OPRT) and orotidine 5'-monophosphate decarboxylase (OMPDC). In most prokaryotes and simple eukaryotes these two enzymes are encoded by separate genes, whereas in mammals they are expressed as a bifunctional gene product called UMP synthase (UMPS), with OPRT at the N terminus and OMPDC at the C terminus. Leishmania and some closely related organisms also express a bifunctional enzyme for these two steps, but the domain order is reversed relative to mammalian UMPS. In this work we demonstrate that L. donovani UMPS (LdUMPS) is an essential enzyme in promastigotes and that it is sequestered in the parasite glycosome. We also present the crystal structure of the LdUMPS in complex with its product, UMP. This structure reveals an unusual tetramer with two head to head and two tail to tail interactions, resulting in two dimeric OMPDC and two dimeric OPRT functional domains. In addition, we provide structural and biochemical evidence that oligomerization of LdUMPS is controlled by product binding at the OPRT active site. We propose a model for the assembly of the catalytically relevant LdUMPS tetramer and discuss the implications for the structure of mammalian UMPS.

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Authors+Show Affiliations

French JB
Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA.
Yates PA
No affiliation info available
Soysa DR
No affiliation info available
Boitz JM
No affiliation info available
Carter NS
No affiliation info available
Chang B
No affiliation info available
Ullman B
No affiliation info available
Ealick SE
No affiliation info available

MeSH

Leishmania donovaniModels, MolecularMultienzyme ComplexesOrotate PhosphoribosyltransferaseOrotidine-5'-Phosphate DecarboxylaseProtein MultimerizationProtein Structure, QuaternaryProtein Structure, TertiaryProtozoan ProteinsUridine Monophosphate

Pub Type(s)

Journal Article
Research Support, N.I.H., Extramural

Language

eng

PubMed ID

21507942

Citation

French, Jarrod B., et al. "The Leishmania Donovani UMP Synthase Is Essential for Promastigote Viability and Has an Unusual Tetrameric Structure That Exhibits Substrate-controlled Oligomerization." The Journal of Biological Chemistry, vol. 286, no. 23, 2011, pp. 20930-41.
French JB, Yates PA, Soysa DR, et al. The Leishmania donovani UMP synthase is essential for promastigote viability and has an unusual tetrameric structure that exhibits substrate-controlled oligomerization. J Biol Chem. 2011;286(23):20930-41.
French, J. B., Yates, P. A., Soysa, D. R., Boitz, J. M., Carter, N. S., Chang, B., Ullman, B., & Ealick, S. E. (2011). The Leishmania donovani UMP synthase is essential for promastigote viability and has an unusual tetrameric structure that exhibits substrate-controlled oligomerization. The Journal of Biological Chemistry, 286(23), 20930-41. https://doi.org/10.1074/jbc.M111.228213
French JB, et al. The Leishmania Donovani UMP Synthase Is Essential for Promastigote Viability and Has an Unusual Tetrameric Structure That Exhibits Substrate-controlled Oligomerization. J Biol Chem. 2011 Jun 10;286(23):20930-41. PubMed PMID: 21507942.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - The Leishmania donovani UMP synthase is essential for promastigote viability and has an unusual tetrameric structure that exhibits substrate-controlled oligomerization. AU - French,Jarrod B, AU - Yates,Phillip A, AU - Soysa,D Radika, AU - Boitz,Jan M, AU - Carter,Nicola S, AU - Chang,Bailey, AU - Ullman,Buddy, AU - Ealick,Steven E, Y1 - 2011/04/19/ PY - 2011/4/22/entrez PY - 2011/4/22/pubmed PY - 2011/8/6/medline SP - 20930 EP - 41 JF - The Journal of biological chemistry JO - J Biol Chem VL - 286 IS - 23 N2 - The final two steps of de novo uridine 5'-monophosphate (UMP) biosynthesis are catalyzed by orotate phosphoribosyltransferase (OPRT) and orotidine 5'-monophosphate decarboxylase (OMPDC). In most prokaryotes and simple eukaryotes these two enzymes are encoded by separate genes, whereas in mammals they are expressed as a bifunctional gene product called UMP synthase (UMPS), with OPRT at the N terminus and OMPDC at the C terminus. Leishmania and some closely related organisms also express a bifunctional enzyme for these two steps, but the domain order is reversed relative to mammalian UMPS. In this work we demonstrate that L. donovani UMPS (LdUMPS) is an essential enzyme in promastigotes and that it is sequestered in the parasite glycosome. We also present the crystal structure of the LdUMPS in complex with its product, UMP. This structure reveals an unusual tetramer with two head to head and two tail to tail interactions, resulting in two dimeric OMPDC and two dimeric OPRT functional domains. In addition, we provide structural and biochemical evidence that oligomerization of LdUMPS is controlled by product binding at the OPRT active site. We propose a model for the assembly of the catalytically relevant LdUMPS tetramer and discuss the implications for the structure of mammalian UMPS. SN - 1083-351X UR - https://www.unboundmedicine.com/medline/citation/21507942/The_Leishmania_donovani_UMP_synthase_is_essential_for_promastigote_viability_and_has_an_unusual_tetrameric_structure_that_exhibits_substrate_controlled_oligomerization_ L2 - https://linkinghub.elsevier.com/retrieve/pii/S0021-9258(19)49156-4 DB - PRIME DP - Unbound Medicine ER -
Grapherence [↓17 ↑59]

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