Photoswitchable PAD inhibitor is a photoactivated protein arginine deiminase (PAD) inhibitor and a derivative of BB-Cl-amidine that contains an azobenzene photoswitch allowing optical control of PAD activity.1 Without photoactivation, it is a weak inhibitor of PAD2 (IC50 = >100 μM) and is less potent than BB-Cl-amidine in inhibiting citrulline production in vitro (kinact KIs = 2,300, 600, 1,000, and 10,510 M-1min-1 for PAD1-4, respectively) and does not inhibit histone H3 citrullination in HEK293T cells overexpressing PAD2 when used at concentrations up to 100 μM. However, it can rapidly be photoactivated with UV-A radiation to the more active cis-isomer, which is an irreversible, competitive inhibitor of histone H3 citrullination with an IC50 value of 9.1 μM.References1. Mondal, S., Parelkar, S.S., Nagar, M., et al. Photochemical control of protein arginine deiminase (PAD) activity. ACS Chem. Biol. 13(4), 1057-1065 (2018). Photoswitchable PAD inhibitor is a photoactivated protein arginine deiminase (PAD) inhibitor and a derivative of BB-Cl-amidine that contains an azobenzene photoswitch allowing optical control of PAD activity.1 Without photoactivation, it is a weak inhibitor of PAD2 (IC50 = >100 μM) and is less potent than BB-Cl-amidine in inhibiting citrulline production in vitro (kinact KIs = 2,300, 600, 1,000, and 10,510 M-1min-1 for PAD1-4, respectively) and does not inhibit histone H3 citrullination in HEK293T cells overexpressing PAD2 when used at concentrations up to 100 μM. However, it can rapidly be photoactivated with UV-A radiation to the more active cis-isomer, which is an irreversible, competitive inhibitor of histone H3 citrullination with an IC50 value of 9.1 μM. References1. Mondal, S., Parelkar, S.S., Nagar, M., et al. Photochemical control of protein arginine deiminase (PAD) activity. ACS Chem. Biol. 13(4), 1057-1065 (2018).
para-amino-Blebbistatin is a more water-soluble form of (S)-4'-nitro-blebbistatin , which is a more stable and less phototoxic form of (-)-blebbistatin .1,2,3 (-)-Blebbistatin is a selective cell-permeable inhibitor of non-muscle myosin II ATPases that rapidly and reversibly inhibits Mg-ATPase activity and in vitro motility of non-muscle myosin IIA and IIB for several species (IC50s = 0.5-5 μM), while poorly inhibiting smooth muscle myosin (IC50 = 80 μM).2,3,4 Through these effects, it blocks apoptosis-related bleb formation, directed cell migration, and cytokinesis in vertebrate cells. However, prolonged exposure to blue light (450-490 nm) results in degradation of blebbistatin to an inactive product via cytotoxic intermediates, which may be problematic for its use in fluorescent live cell imaging applications.5,6 The addition of a 4'-amino group increases its water solubility, decreases the inherent fluorescence, stabilizes the molecule to circumvent its degradation by prolonged blue light exposure, and decreases its phototoxicity while retaining the in vitro and in vivo activity of blebbistatin.7 para-amino-Blebbistatin has the same stereochemistry as the active (-)-blebbistatin enantiomer. |1. Várkuti, B.H., Képiró, M., Horváth, I.á., et al. A highly soluble, non-phototoxic, non-fluorescent blebbistatin derivative. Sci. Rep. 6:26141, (2016).|2. Straight, A.F., Cheung, A., Limouze, J., et al. Dissecting temporal and spatial control of cytokinesis with a myosin II inhibitor. Science 299(5613), 1743-1747 (2003).|3. Kovács, M., Tóth, J., Hetényi, C., et al. Mechanism of blebbistatin inhibition of myosin II. J. Biol. Chem. 279(34), 35557-35563 (2004).|4. Limouze, J., Straight, A.F., Mitchison, T., et al. Specificity of blebbistatin, an inhibitor of myosin II. J. Muscle Res. Cell Motil. 25(4-5), 337-341 (2004).|5. Kolega, J. Phototoxicity and photoinactivation of blebbistatin in UV and visible light. Biochem. Biophys. Res. Commun. 320(3), 1020-1025 (2004).|6. Sakamoto, T., Limouze, J., Combs, C.A., et al. Blebbistatin, a myosin II inhibitor, is photoinactivated by blue light. Biochemistry 44(2), 584-588 (2005).|7. Verhasselt, S., Roman, B.I., Bracke, M.E., et al. Improved synthesis and comparative analysis of the tool properties of new and existing D-ring modified (S)-blebbistatin analogs. Eur. J. Med. Chem. 136, 85-103 (2017).
2',6'-Dihydroxy-4'-methoxyacetophenone is a phytoalexin after fungal inoculation with Botrytis cinerea or UV light irradiation, it has spore germination inhibition on Botrytis cinerea and Phomopsis perniciosa, with ED50 values of 45 and 410 uM, respective