15N/13C NOESY Protein NMR Spectroscopy by Application of the Covariance Transform David A. Snyder,† Yingqi Xu,‡ Daiwen Yang,‡ and Rafael Brüschweiler*,† Department of Chemistry and Biochemistry & National High Magnetic Field Laboratory, Florida State UniVersity, Tallahassee, Florida 32306, and Department of Biological Sciences, National UniVersity of Singapore, 14 Science DriVe 4, Singapore 117543

6-(3-Methyltriaz-1-en-1-yl)-1H-benzo[de]isoquinoline-1,3(2H)-dione referred to as EG22 (8a), is an open-chain 3-alkyl-1,2,3-triazene termed "combi-molecule" designed to inhibit poly(adenosine diphosphate ribose) polymerase (PARP) and damage DNA. To delay its hydrolysis, acetylation of N3 was required. Being a monoalkyl-1,2,3-triazene, EG22 could assume two tautomers in solution or lose nitrogen...

Recent developments in multidimensional heteronuclear NMR spectroscopy and large-scale synthesis of uniformly 13C- and 15N-labeled oligonucleotides have greatly improved the prospects for determination of the solution structure of RNA. However, there are circumstances in which it may be advantageous to label only a segment of the entire RNA chain. For example, in a larger RNA molecule the struc...

Flows of carbon and nitrogen in a natural phytoplankton assemblage from the plume of the Scheldt estuary were followed during and after a light-induced bloom by measuring changes in concentrations and stable isotope ratios in mesocosms after addition of 13C (as bicarbonate or glucose) and 15N (as ammonium or nitrate). Addition of 13C-bicarbonate showed a strong coupling between algal primary pr...

The wealth of field studies using stable isotopes to make inferences about animal diets require controlled validation experiments to make proper interpretations. Despite several pleas in the literature for such experiments, validation studies are still lagging behind, notably in consumers dwelling in chemosynthesis-based ecosystems. In this paper we present such a validation experiment for the ...

Mutations in the human SLC26A4/Pendrin polypeptide (hPDS) cause Pendred Syndrome /DFNB4, syndromic deafness with enlargement of the vestibular aqueduct and low-penetrance goiter. Here we present data on cloning, protein overexpression and purification, refolding, and biophysical characterization of the recombinant hPDS STAS domain lacking its intrinsic variable sequence (STAS-ΔIVS). We report a...

CONTEXT The terrestrial planets, comets, and meteorites are significantly enriched in 15N compared to the Sun and Jupiter. While the solar and jovian nitrogen isotope ratio is believed to represent the composition of the protosolar nebula, a still unidentified process has caused 15N-enrichment in the solids. Several mechanisms have been proposed to explain the variations, including chemical fra...