Affibody Molecules for In vivo Characterization of HER2-Positive Tumors by Near-Infrared Imaging.
AuthorsLee SB, Hassan M, Fisher R, Chertov O, Chernomordik V, Kramer-Marek G, Gandjbakhche A, Capala J,
JournalClin Cancer Res
PubMed ID18559604
'PURPOSE: HER2 overexpression has been associated with a poor prognosis and resistance to therapy in breast cancer patients. We are developing molecular probes for in vivo quantitative imaging of HER2 receptors using near-infrared (NIR) optical imaging. The goal is to provide probes that will minimally interfere with the studied system, ... More
Crystal structure of tRNA m1G9 methyltransferase Trm10: insight into the catalytic mechanism and recognition of tRNA substrate.
AuthorsShao Z, Yan W, Peng J, Zuo X, Zou Y, Li F, Gong D, Ma R, Wu J, Shi Y, Zhang Z, Teng M, Li X, Gong Q,
Journal
PubMed ID24081582
Transfer RNA (tRNA) methylation is necessary for the proper biological function of tRNA. The N(1) methylation of guanine at Position 9 (m(1)G9) of tRNA, which is widely identified in eukaryotes and archaea, was found to be catalyzed by the Trm10 family of methyltransferases (MTases). Here, we report the first crystal ... More
Chemically modified firefly luciferase is an efficient source of near-infrared light.
AuthorsBranchini BR, Ablamsky DM, Rosenberg JC,
JournalBioconjug Chem
PubMed ID20936788
Bioluminescence and bioluminescence resonance energy transfer (BRET) are two naturally occurring light emission phenomena that have been adapted to a wide variety of important research applications including in vivo imaging and enzyme assays. The luciferase enzyme from the North American firefly, which produces yellow-green light, is a key component of ... More
Identification of cysteines involved in S-nitrosylation, S-glutathionylation, and oxidation to disulfides in ryanodine receptor type 1.
AuthorsAracena-Parks P, Goonasekera SA, Gilman CP, Dirksen RT, Hidalgo C, Hamilton SL,
JournalJ Biol Chem
PubMed ID17071618
The skeletal muscle Ca(2+)-release channel (ryanodine receptor type 1 (RyR1)) is a redox sensor, susceptible to reversible S-nitrosylation, S-glutathionylation, and disulfide oxidation. So far, Cys-3635 remains the only cysteine residue identified as functionally relevant to the redox sensing properties of the channel. We demonstrate that expression of the C3635A-RyR1 mutant ... More
Transmembrane voltage regulates binding of annexin V and lactadherin to cells with exposed phosphatidylserine.
AuthorsSmith C, Gibson DF, Tait JF,
JournalBMC Biochem
PubMed ID19222854
BACKGROUND: Cells expose phosphatidylserine during apoptosis. The voltage across the plasma membrane also decreases or disappears during apoptosis, but the physiological significance of this is unknown. RESULTS: Here we show that transmembrane potential regulates membrane binding of two unrelated proteins that recognize exposed phosphatidylserine on apoptotic cells. In Jurkat T ... More
Efficiencies of fluorescence resonance energy transfer and contact-mediated quenching in oligonucleotide probes.
AuthorsMarras SA, Kramer FR, Tyagi S
JournalNucleic Acids Res
PubMed ID12409481
An important consideration in the design of oligonucleotide probes for homogeneous hybridization assays is the efficiency of energy transfer between the fluorophore and quencher used to label the probes. We have determined the efficiency of energy transfer for a large number of combinations of commonly used fluorophores and quenchers. We ... More
A robust method for production of MHC tetramers with small molecule fluorophores.
AuthorsRamachandiran V, Grigoriev V, Lan L, Ravkov E, Mertens SA, Altman JD
JournalJ Immunol Methods
PubMed ID17187819
Tetramers of major histocompatibility complex molecules (MHC) are now well-established reagents for the detection of antigen-specific T cells by flow cytometry. MHC tetramers are prepared by mixing enzymatically biotinylated MHC molecules with commercial preparations of streptavidin, usually conjugated to a fluorescent phycobiliprotein such as phycoerythrin (PE) or allophycocyanin (APC). While ... More
Synthesis, characterization, and application of cy-dye- and alexa-dye-labeled hongotoxin(1) analogues. The first high affinity fluorescence probes for voltage-gated K+ channels.
AuthorsPragl B, Koschak A, Trieb M, Obermair G, Kaufmann WA, Gerster U, Blanc E, Hahn C, Prinz H, Schütz G, Darbon H, Gruber HJ, Knaus HG
JournalBioconjug Chem
PubMed ID12009929
Hongotoxin(1) (HgTX(1)), a 39-residue peptide recently isolated from the venom of Centruroides limbatus, blocks the voltage-gated K+ channels K(v)1.1, K(v)1.2, and K(v)1.3 at picomolar toxin concentrations (Koschak, A., Bugianesi, R. M., Mitterdorfer, J., Kaczorowski, G. J., Garcia, M. L., and Knaus, H. G. (1998) J. Biol. Chem. 273, 2639-2644). In ... More
Spectroscopic observations of ferric enterobactin transport.
AuthorsCao Z, Warfel P, Newton SM, Klebba PE
JournalJ Biol Chem
PubMed ID12409288
We characterized the uptake of ferric enterobactin (FeEnt), the native Escherichia coli ferric siderophore, through its cognate outer membrane receptor protein, FepA, using a site-directed fluorescence methodology. The experiments first defined locations in FepA that were accessible to covalent modification with fluorescein maleimide (FM) in vivo; among 10 sites that ... More