skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Targeting S-adenosylmethionine biosynthesis with a novel allosteric inhibitor of Mat2A

Abstract

S-Adenosyl-L-methionine (SAM) is an enzyme cofactor used in methyl transfer reactions and polyamine biosynthesis. The biosynthesis of SAM from ATP and L-methionine is performed by the methionine adenosyltransferase enzyme family (Mat; EC 2.5.1.6). Human methionine adenosyltransferase 2A (Mat2A), the extrahepatic isoform, is often deregulated in cancer. We identified a Mat2A inhibitor, PF-9366, that binds an allosteric site on Mat2A that overlaps with the binding site for the Mat2A regulator, Mat2B. Studies exploiting PF-9366 suggested a general mode of Mat2A allosteric regulation. Allosteric binding of PF-9366 or Mat2B altered the Mat2A active site, resulting in increased substrate affinity and decreased enzyme turnover. These data support a model whereby Mat2B functions as an inhibitor of Mat2A activity when methionine or SAM levels are high, yet functions as an activator of Mat2A when methionine or SAM levels are low. The ramification of Mat2A activity modulation in cancer cells is also described.

Authors:
ORCiD logo; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
Sponsoring Org.:
INDUSTRY
OSTI Identifier:
1405006
Resource Type:
Journal Article
Resource Relation:
Journal Name: Nature Chemical Biology; Journal Volume: 13; Journal Issue: 7
Country of Publication:
United States
Language:
ENGLISH
Subject:
59 BASIC BIOLOGICAL SCIENCES; 60 APPLIED LIFE SCIENCES

Citation Formats

Quinlan, Casey L., Kaiser, Stephen E., Bolaños, Ben, Nowlin, Dawn, Grantner, Rita, Karlicek-Bryant, Shannon, Feng, Jun Li, Jenkinson, Stephen, Freeman-Cook, Kevin, Dann, Stephen G., Wang, Xiaoli, Wells, Peter A., Fantin, Valeria R., Stewart, Al E., and Grant, Stephan K.. Targeting S-adenosylmethionine biosynthesis with a novel allosteric inhibitor of Mat2A. United States: N. p., 2017. Web. doi:10.1038/nchembio.2384.
Quinlan, Casey L., Kaiser, Stephen E., Bolaños, Ben, Nowlin, Dawn, Grantner, Rita, Karlicek-Bryant, Shannon, Feng, Jun Li, Jenkinson, Stephen, Freeman-Cook, Kevin, Dann, Stephen G., Wang, Xiaoli, Wells, Peter A., Fantin, Valeria R., Stewart, Al E., & Grant, Stephan K.. Targeting S-adenosylmethionine biosynthesis with a novel allosteric inhibitor of Mat2A. United States. doi:10.1038/nchembio.2384.
Quinlan, Casey L., Kaiser, Stephen E., Bolaños, Ben, Nowlin, Dawn, Grantner, Rita, Karlicek-Bryant, Shannon, Feng, Jun Li, Jenkinson, Stephen, Freeman-Cook, Kevin, Dann, Stephen G., Wang, Xiaoli, Wells, Peter A., Fantin, Valeria R., Stewart, Al E., and Grant, Stephan K.. Mon . "Targeting S-adenosylmethionine biosynthesis with a novel allosteric inhibitor of Mat2A". United States. doi:10.1038/nchembio.2384.
@article{osti_1405006,
title = {Targeting S-adenosylmethionine biosynthesis with a novel allosteric inhibitor of Mat2A},
author = {Quinlan, Casey L. and Kaiser, Stephen E. and Bolaños, Ben and Nowlin, Dawn and Grantner, Rita and Karlicek-Bryant, Shannon and Feng, Jun Li and Jenkinson, Stephen and Freeman-Cook, Kevin and Dann, Stephen G. and Wang, Xiaoli and Wells, Peter A. and Fantin, Valeria R. and Stewart, Al E. and Grant, Stephan K.},
abstractNote = {S-Adenosyl-L-methionine (SAM) is an enzyme cofactor used in methyl transfer reactions and polyamine biosynthesis. The biosynthesis of SAM from ATP and L-methionine is performed by the methionine adenosyltransferase enzyme family (Mat; EC 2.5.1.6). Human methionine adenosyltransferase 2A (Mat2A), the extrahepatic isoform, is often deregulated in cancer. We identified a Mat2A inhibitor, PF-9366, that binds an allosteric site on Mat2A that overlaps with the binding site for the Mat2A regulator, Mat2B. Studies exploiting PF-9366 suggested a general mode of Mat2A allosteric regulation. Allosteric binding of PF-9366 or Mat2B altered the Mat2A active site, resulting in increased substrate affinity and decreased enzyme turnover. These data support a model whereby Mat2B functions as an inhibitor of Mat2A activity when methionine or SAM levels are high, yet functions as an activator of Mat2A when methionine or SAM levels are low. The ramification of Mat2A activity modulation in cancer cells is also described.},
doi = {10.1038/nchembio.2384},
journal = {Nature Chemical Biology},
number = 7,
volume = 13,
place = {United States},
year = {Mon May 29 00:00:00 EDT 2017},
month = {Mon May 29 00:00:00 EDT 2017}
}
  • Adenine methylation of GATC sequences in DNA is carried out by the DNA adenine methyltransferase with the methyl group source being the cofactor S-adenosylmethionine. The authors report 3H NMR studies on the interaction of DNA adenine methyltransferase with S-adenosylmethionine and the reaction when the ternary complex is formed with an oligonucleotide containing a GATC site. The methylation reaction was also studied in the presence of a competitive inhibitor and this showed two successive stages involved in the methylation and two sites of binding for S-adenosylmethionine.
  • {delta}-Aminolevulinic acid and trimethylisobacteriochlorin are converted by cell-free protein preparations from pseudomonas denitrificans into a metal-free pigment, precorrin-6x. This pigment, which accumulates when the cell-free system lacks NADPH, can be enzymically converted in high yield (>50%) into hydrogenobyrinic acid by the complete enzyme preparation. Double-labeling experiments establish that precorrin-6x carries five C-methyl groups, which appear at C-1, C-2, C-7, C-12{alpha}, and C-17 of the hydrogenobyrinic acid formed enzymically from precorrin-6x. This precursor of the corrin macrocycle is at the dehydrocorrin level of oxidation, has undergone ring contraction and extrusion of C-20, but still carries the acetic acid side chain atmore » C-12. It is demonstrated that the conversion of precorrin-6x into hydrogenobyrinic acid specifically requires and NADPH-dependent reduction step.« less
  • No abstract prepared.
  • Highlights: • L. donovani spermidine synthase and S-adenosylmethionine decarboxylase have been cloned and purified. • S-adenosylmethionine decarboxylase has autocatalytic property. • GST pull down assay shows the two proteins to form a metabolon. • Isothermal titration calorimetry shows that binding was exothermic having K{sub d} value of 0.4 μM. • Interaction confirmed by fluorescence spectroscopy and size exclusion chromatography. - Abstract: Polyamine biosynthesis pathway has long been considered an essential drug target for trypanosomatids including Leishmania. S-adenosylmethionine decarboxylase (AdoMetDc) and spermidine synthase (SpdSyn) are enzymes of this pathway that catalyze successive steps, with the product of the former, decarboxylated S-adenosylmethioninemore » (dcSAM), acting as an aminopropyl donor for the latter enzyme. Here we have explored the possibility of and identified the protein–protein interaction between SpdSyn and AdoMetDc. The protein–protein interaction has been identified using GST pull down assay. Isothermal titration calorimetry reveals that the interaction is thermodynamically favorable. Fluorescence spectroscopy studies also confirms the interaction, with SpdSyn exhibiting a change in tertiary structure with increasing concentrations of AdoMetDc. Size exclusion chromatography suggests the presence of the complex as a hetero-oligomer. Taken together, these results suggest that the enzymes indeed form a heteromer. Computational analyses suggest that this complex differs significantly from the corresponding human complex, implying that this complex could be a better therapeutic target than the individual enzymes.« less