研究领域
Organic and Bioorganic Chemistry
We report the synthesis of the first fluorescently labeled conjugates of risedronate (1), using an epoxide linker strategy enabling conjugation of 1 via its pyridyl nitrogen with the label (carboxyfluorescein). Unlike prior approaches to create fluorescent bisphosphonate probes, the new linking chemistry did not abolish the ability to inhibit protein prenylation in vitro, while significantly retaining hydroxyapatite affinity. The utility of a fluorescent 1 conjugate in visualizing osteoclast resorption in vitro was demonstrated.
Nucleotide Analogues: A "Toolkit" to Study DNA Polymerase
The mechanism of DNA polymerase -catalyzed nucleotidyl transfer consists of chemical steps involving primer 3'OH deprotonation, nucleophilic attack, and pyrophosphate leaving-group elimination, preceded by dNTP binding which induces a large-amplitude conformational change for Watson-Crick nascent base pairs. Ambiguity in the nature of the rate-limiting step and active-site structural differences between correct and incorrect base-paired transition states remain obstacles to understanding DNA replication fidelity. Analogues of dGTP where the - bridging oxygen is replaced with fluorine-substituted methylene groups have been shown to probe the contribution of leaving-group elimination to the overall catalytic rate (Biochemistry 46, 461-471). Here, the analysis is expanded substantially to include a broad range of halogen substituents with disparate steric and electronic properties. Evaluation of linear free energy relationships for incorporation of dGTP analogues opposite either template base C or T reveals a strong correlation of log(kpol) to leaving group pKa. Significantly different kpol behavior is observed with a subset of the analogues, with magnitude dependent on the identity of the nascent base pair. This observation, and the absence of an analogous effect on ground state analogue binding (Kd values), points to active-site structural differences at the chemical transition state. Reduced catalysis with bulky halo-containing substrates is manifested in the fidelity of T-G incorporation, where the CCl2-bridging analogue shows a 27-fold increase in fidelity over the natural dGTP. Solvent pH and deuterium isotope effect data are also used to evaluate mechanistic differences between correct and mispaired incorporation.
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Seamon KJ, Hansen EC, Kadina AP, Kashemirov BA, McKenna CE, Bumpus NN, Stivers JT. "Small Molecule Inhibition of SAMHD1 dNTPase by Tetramer Destabilization." J Am Chem Soc. 2014 Jul 16;136(28):9822-5.
Bae S, Sun S, Aghaloo T, Oh JE, McKenna CE, Kang MK, Shin KH, Tetradis S, Park NH, Kim RH. "Development of oral osteomucosal tissue constructs in vitro and localization of fluorescently-labeled bisphosphonates to hard and soft tissue.", Int J Mol Med. 2014 Aug;34(2):559-63.
Hwang CS, Kashemirov BA, McKenna CE. "On the Observation of Discrete Fluorine NMR Spectra for Uridine 5'-β,γ-Fluoromethylenetriphosphate Diastereomers at Basic pH", J Org Chem. 2014 Jun 6;79(11):5315-9.
Oertell K, Chamberlain BT, Wu Y, Ferri E, Kashemirov BA, Beard WA, Wilson SH, McKenna CE, Goodman MF, "The Transition-State in DNA Polymerase β Catalysis: Rate-limiting Chemistry Altered by Base-Pair Configuration", Biochemistry, 2014, 53 (11), pp 1842–1848.
I.S. Krylov, C.E. McKenna, "Enzymatically activated phosphate and phosphonate prodrugs", Chapter in: "Enzyme technology for biotechnology and pharmaceutical applications", Vol. 2, eds. J.R. McCarthy, G. Yang, W.-K. Yeh, Wiley Interscience, New York, NY, doi: 10.1002/9781118739907.ch7 (2014).
Vermeer JA, Jansen ID, Marthi M, Coxon FP, McKenna CE, Sun S, de Vries TJ, Everts V. "Jaw bone marrow-derived osteoclast precursors internalize more bisphosphonate than long-bone marrow precursors." Bone. 2013, 57, 242-51.
Ni F, Lee CC, Hwang CS, Hu Y, Ribbe MW, McKenna CE. "Reduction of fluorinated cyclopropene by nitrogenase." J Am Chem Soc. 2013, 135, 10346-10352.
Emadali A, Rousseaux S, Bruder-Costa J, Rome C, Duley S, Hamaidia S, Betton P, Debernardi A, Leroux D, Bernay B, Kieffer-Jaquinod S, Combes F, Ferri E, McKenna CE, Petosa C, Bruley C, Garin J, Ferro M, Gressin R, Callanan MB, Khochbin S. "Identification of a novel BET bromodomain inhibitor-sensitive, gene regulatory circuit that controls Rituximab response and tumour growth in aggressive lymphoid cancers." EMBO Mol Med. 2013, 5 (8), 1180–1195.
Krylov IS, Kashemirov BA, Hilfinger JM, McKenna CE. "Evolution of an amino acid based prodrug approach: stay tuned." Mol. Pharm. 2013, 10, 445-58. (cover)
Hokugo A, Sun S, Park S, McKenna CE, Nishimura I. "Equilibrium-dependent bisphosphonate interaction with crystalline bone mineral explains anti-resorptive pharmacokinetics and prevalence of osteonecrosis of the jaw in rats." Bone. 2013, 53, 59-68.
Arora DK, Syed I, Machhadieh B, McKenna CE, Kowluru A. "Rab-geranylgeranyl transferase regulates glucose-stimulated insulin secretion from pancreatic β cells." Islets. 2012, 4, 354-358.
Ward SE, Kim HS, Komurov K, Mendiratta S, Tsai PL, Schmolke M, Satterly N, Manicassamy B, Forst CV, Roth MG, García-Sastre A, Blazewska KM, McKenna CE, Fontoura BM, White MA. "Host modulators of H1N1 cytopathogenicity". PLoS One. 2012, 7 (8).
Oertell K, Wu Y, Zakharova VM, Kashemirov BA, Shock DD, Beard WA, Wilson SH, McKenna CE, Goodman MF. "Effect of β,γ-CHF and β,γ-CHCl dGTP halogen atom stereochemistry on the transition-state of DNA polymerase β". Biochemistry. 2012, 51, 8491-8501.
Roelofs AJ, Stewart C, Sun S, Blazewska KM, Kashemirov BA, McKenna CE, Russell RGG, Rogers MJ, Lundy MW, Ebetino FH, Coxon FP. "Influence of bone affinity on skeletal distribution of fluorescently-labeled bisphosphonate analogues". J Bone Miner Res. 2012, 27(4), 835-47.
Y. Wu, V.M. Zakharova, B.A. Kashemirov, M.F. Goodman, V.K. Batra, S.H. Wilson, C.E. McKenna. "β,γ-CHF- and CHCl-dGTP diastereomers: synthesis, discrete 31P NMR signatures and absolute configurations of new stereochemical probes for DNA polymerases", J Am Chem Soc. 2012, 134 (21), 8734–8737.
J. Turek, F.H. Ebetino, M.W. Lundy, S. Sun, B.A. Kashemirov, C.E. McKenna, M.A. Gallant, L.I. Plotkin, T. Belido, X. Duan, R.G.G. Russell, D. Burr, M. Allen. "Bisphosphonate Binding Affinity Affects Drug Distribution in Both Intracortical and Trabecular Bone of Rabbits", Calcif Tissue Int. 2012, 90, 202-210
V.K. Batra, D.D. Shock, W.A. Beard, C.E. McKenna, S.H. Wilson. "Binary complex crystal structure of DNA polymerase β reveals multiple conformations of the templating 8-oxoguanine lesion", Proc Natl Acad Sci U S A. 2012, 109, 113-118.
I.S. Krylov, V.M. Zakharova, M. Serpi, R. Haiges, B.A. Kashemirov, C.E. McKenna. "The structure of cyclic nucleoside phosphonate ester prodrugs: an inquiry", J Org Chem. 2012, 77, 684-689.
B.T. Chamberlain, V.K. Batra, W.A. Beard, A.P. Kadina, D.D. Shock, B.A. Kashemirov, C.E. McKenna. "Stereospecific Formation of a Ternary Complex of (S)-α,β-fluoromethylene-dATP with DNA Pol β", ChemBioChem. 2012, 13, 528-530.
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