Felicia A. Etzkorn

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Based on recent X-ray structural information, six site-directed mutants of human cyclophilin A (hCyPA) involving residues in the putative active site--H54, R55, F60, Q111, F113, and H126--have been constructed, overexpressed, and purified from Escherichia coli to homogeneity. The proteins W121A (Liu, J., Chen, C.-M., & Walsh, C.T., 1991a, Biochemistry 30,(More)
Protein serine-threonine kinase casein kinase II (CK2) is involved in a myriad of cellular processes including cell growth and proliferation through its phosphorylation of hundreds of substrates, yet how CK2 function is regulated is poorly understood. Here we report that the CK2 catalytic subunit CK2α is modified by O-linked β-N-acetyl-glucosamine(More)
The recently isolated Escherichia coli murB gene (Pucci et al., 1992) has been cloned into an expression vector and the encoded UDP-N-acetylenolpyruvylglucosamine reductase (EC 1.1.1.158) was overproduced to about 10% of soluble cell protein. The encoded 38-kDa protein has been purified to near homogeneity. It was found to be a monomer and to contain(More)
Synaptic plasticity induced by cocaine and other drugs underlies addiction. Here we elucidate molecular events at synapses that cause this plasticity and the resulting behavioral response to cocaine in mice. In response to D1-dopamine-receptor signaling that is induced by drug administration, the glutamate-receptor protein metabotropic glutamate receptor 5(More)
Stereoisomeric cis and trans substrate analogues for Pin1 were designed and synthesized. The central phosphoSer-Pro core of the Pin1 substrate was replaced by cis and trans amide isosteres in Ac-Phe-Phe-pSer-Psi[(Z and E)CH=C]-Pro-Arg-NH(2), 1 and 2, peptidomimetics. They were synthesized on solid phase in 17% yield for the cis analogue 1, and 16% yield for(More)
Quantitative determination of dissociation constants for DNA-protein complexes will help clarify the molecular mechanisms of transcription, replication and DNA repair. A practical capillary electrophoresis mobility shift assay (CEMSA) for protein-DNA affinities free in solution is presented. The method is fast and simple, precise and general. The speed (<2(More)
[structure: see text] Three analogues of suberoyl anilide hydroxamic acid (SAHA) with phosphorus metal-chelating functionalities were synthesized as inhibitors of histone deacetylases (HDACs). The compounds showed weak activity for HeLa nuclear extracts (IC(50) = 0.57-6.1 mM), HDAC8 (IC(50) = 0.28-0.41 mM), and histone-deacetylase-like protein (HDLP, IC(50)(More)
Pin1 specifically catalyzes the cis/trans isomerization of phospho-Ser/Thr-Pro bonds and plays an important role in many cellular events through the effects of conformational change on the function of its biological substrates, including cell division cycle 25 C (Cdc25C), c-Jun and p53. Pin1 is overexpressed in many human cancer tissues, including breast,(More)
We investigated the effect of restricting cis-trans proline isomerization on collagen triple-helix stability. The Pro residues at the Xaa and Yaa positions of an (Xaa-Yaa-Gly) triplet were replaced by a Pro-trans-Pro alkene isostere in the host-guest peptide, H-(Pro-Pro-Gly)(10)-OH. The resulting alkene isostere peptide had a T(m) value 53.6 degrees C lower(More)
Fmoc-pSer-Psi[(Z)CHC]-Pro-(2)-N-(3)-ethylaminoindole 1, showed moderate inhibition towards the mitotic regulator, Pin1 (IC(50)=28.3microM). To improve the cell permeability, the charged phosphate was masked as the bis-pivaloyloxymethyl (POM) phosphate in Fmoc-(bisPOM)-pSer-Psi[(Z)CHC]-Pro-(2)-N-(3)-ethylaminoindole 2. Antiproliferative activity towards(More)