Methods: Synthesis of DOTA-AE105-NH2, and NODAGA-AE105-NH2, was based on solid-phase peptide synthesis protocols using the Fmoc strategy. (GaCl3)-Ga-68 was eluted from a Ge-68/Ga-68 generator. The eluate was either concentrated on a cation-exchange column or fractionated and used directly for labeling. For in vitro characterization of both tracers, partition coefficient, buffer and plasma stability, uPAR binding affinity and cell uptake were determined. To characterize the ill

vivo properties, dynamic microPET selleck imaging was carried out in nude mice bearing human glioma U87MG tumor xenograft.

Results: In vitro experiments revealed uPAR binding affinities in the lower nM range for both conjugated peptides and identical to AE105. Labeling of DOTA-AE105-NH2 and NODAGA-AE105-NH2 with Ga-68 was done at 95 degrees C and room temperature, respectively. The highest radiochemical yield and purity were obtained using fractionated elution, whereas a negative effect of acetone on labeling efficiency for NODAGA-AE105-NH2

was observed. CUDC-907 Good stability in phosphate-buffered saline and mouse plasma was observed. High cell uptake was found for both tracers in U87MG tumor cells. Dynamic microPET imaging demonstrated good tumor-to-background ratio for both tracers. Tumor uptake was 2.1% ID/g and 1.3% ID/g 30 min postinjection and 2.0% ID/g and 1.1% ID/g 60 min postinjection for Ga-68-NODAGA-AE105-NH2 and Ga-68-DOTA-AE105-NH2, respectively. A significantly higher tumor-to-muscle ratio (P<.05) was found for Ga-68-NODAGA-AE105-NH2 60 min postinjection.

Conclusions: TCL The use of Ga-68-DOTA-AE105-NH2 and Ga-68-NODAGA-AE105-NH2 as the first gallium-68 labeled uPAR radiotracers for noninvasive PET imaging is reported, which combine versatility with good imaging properties. These new tracers thus constitute an interesting alternative to the Cu-64-labeled version (Cu-64-DOTA-AE105 and 64Cu-DOTA-AE105-NH2) for detecting uPAR expression in tumor tissue. In our hands, the

fractionated elution approach was superior for labeling of peptides, and Ga-68-NODAGA-AE105-NH2 is the favored tracer as it provides the highest tumor-to-background ratio. (C) 2012 Elsevier Inc. All rights reserved.”
“Recent phosphoproteomics studies of several bacteria] species have firmly established protein phosphorylation on Ser/Thr/Tyr residues as a PTM in bacteria. In particular, our recent reports on the Scr/Thr/Tyr phosphoproteomes of bacterial model organisms Bacillus subtilis and Escherichia coli detected over 100 phosphorylation events in each of the bacterial species. Here we extend our analyses to Lactococcus lactis, a lactic acid bacterium widely employed by the food industry, in which protein phosphorylation at Ser/Thr/Tyr residues was barely studied at all. Despite the lack of almost any prior evidence of Ser/Thr/Tyr protein phosphorylation in L.