Myeloperoxidase Chlorination Fluorometric Assay Kit Reference: 10006438-2 Cayman’s Myeloperoxidase Chlorination Fluorometric Assay provides a convenient fluorescence-based method for detecting the MPO chlorination activity in both crude cell lysates and purified enzyme preparations. The assay utilizes the non-fluorescent 2-[6-(4-aminophenoxy)-3-oxo-3H-xanthen-9-yl]-benzoic acid (APF), which is selectively cleaved by hypochlorite (-OCl) to yield the highly fluorescent compound fluorescein.(11242) Fluorescein fluorescence is analyzed with an excitation wavelength of 480-495 nm and an emission wavelength of 515-525 nm. The kit includes a MPO-specific inhibitor for distinguishing MPO activity from MPO-independent fluorescence.
HAT Inhibitor Screening Assay Kit Reference: 10006515-96 Cayman’s HAT Inhibitor Screening Assay provides a fast, fluorescence-based method for evaluating PCAF HAT inhibitors. The procedure requires only three easy steps, all performed in the same microplate. In the first step of the protocol, HAT is incubated with acetyl-CoA and the histone H3 peptide. During this time, HAT catalyzes the enzymatic transfer of acetyl groups from acetyl-CoA to the H3 peptide producing an acetylated peptide and CoASH. Following addition of isopropanol to stop the enzymatic reaction, CPM is added to the wells of the plate. CPM reacts with the free thiol groups present on CoASH forming a highly fluorescent product that is detected using excitation and emission wavelengths of 360-390 and 450-470 nm, respectively.
S-Nitrosylated Protein Detection Kit (Biotin Switch) Reference: 10006518-1 Cayman’s S-Nitrosylated Protein Detection Kit (Biotin Switch) employs a modification of the Jaffrey et al. 'Biotin-switch' method to allow for the direct visualization of S-nitrosylated proteins in whole cells or tissues, as well as by WB analysis. Using this method, free SH groups are first blocked (an addition of 125.1 amu per residue) and any S-NO bonds present in the sample are then cleaved. Biotinylation of the newly formed SH groups (an addition of 523.6 amu per residue) provides the basis for visualization using streptavidin-based colorimetric or fluorescence detection.