cyanine-dye-3 and maleimide

Two 2'-deoxyuridines as new building blocks for automated DNA synthesis carry a small aryltetrazole as "photoclickable" group at their 5-positions. The postsynthetic "photoclick" labeling of such presynthesized DNA using a maleimide-modified Cy3 dye shows an up to 17-fold fluorogenicity due to an energy transfer between the pyrazoline moiety and the Cy3 fluorophore in the DNA products. This concept is also applicable to other maleimide-modified dyes.

Topics: Base Sequence; Carbocyanines; Cycloaddition Reaction; Deoxyuridine; DNA; Fluorescent Dyes; Maleimides; Photochemical Processes; Staining and Labeling

Protein S-nitrosation is a reversible post-translation modification critical for redox-sensitive cell signaling that is typically studied using the Biotin Switch method. This method and subsequent modifications usually require avidin binding or Western blot analysis to detect biotin labeled proteins. We describe here a modification of the Biotin Switch assay that eliminates the need for Western blot or avidin enrichment protocols and allows direct comparison of the S-nitrosation state proteins from two different samples in the same gel lane or on the same 2D gel. This S-FLOS method offers detection, identification and quantification of S-nitrosated proteins, with the potential for site-specific identification of nitrosation events.

Topics: Animals; Biotin; Brain Chemistry; Carbocyanines; Databases, Protein; Fluorescence; Maleimides; Mice; Nitric Oxide; Nitric Oxide Synthase; Nitrosation; Oxidation-Reduction; Protein Processing, Post-Translational; Proteins; Proteomics; S-Nitrosothiols; Silver Staining; Tandem Mass Spectrometry

Topics: Animals; Caenorhabditis elegans; Carbocyanines; Fluorescent Dyes; Green Fluorescent Proteins; Kinesins; Luminescent Proteins; Male; Maleimides; Microscopy, Fluorescence; Microscopy, Video; Molecular Motor Proteins; Movement; Mutagenesis, Site-Directed; Protein Biosynthesis; Protein Isoforms; Recombinant Fusion Proteins; Sea Urchins; Sperm Tail