Amino and carboxy functionalized modified nucleosides: A potential class of inhibitors for angiogenin
作者:Joy Debnath、Swagata Dasgupta、Tanmaya Pathak
DOI:10.1016/j.bioorg.2013.11.005
日期:2014.2
The 3'-amino and carboxy functionalize thymidines execute their ribonucleolytic inhibition activity for angiogenin. These modified nucleosidic molecules inhibit the ribonucleolytic activity of angiogenin in a competitive manner like the other conventional nucleotidic inhibitors, which have been confirmed from kinetic experiments. The improved inhibition constant (K-i) values 427 +/- 7, 775 +/- 6 mu M clearly indicate modified nucleosides are an obvious option for the designing of inhibitors of angiogenesis process. The chorioallantoic membrane (CAM) assay qualitatively suggests that amino functionalized nucleosides have an effective potency to inhibited angiogenin-induced angiogenesis. Docking studies further demonstrate the interaction of their polar amino group with the P-1 site residues of angiogenin, i.e., His-13 and His-114 residues. (C) 2013 Elsevier Inc. All rights reserved.
Inhibition of ribonuclease A by nucleoside–dibasic acid conjugates
作者:Joy Debnath、Swagata Dasgupta、Tanmaya Pathak
DOI:10.1016/j.bmc.2009.08.018
日期:2009.9
We report the inhibition of the ribonucleolytic activity of ribonuclease A (RNase A) by nucleoside-dibasic acid conjugates for the first time. Agarose gel and precipitation assays show that the spacer length and the pK(a) of the carboxylic group have an important role in the inhibitory capacity. Kinetic experiments indicate a competitive mode of inhibition with inhibition constant (K-i) value of 132 +/- 3 mu M for Oxa-aT. Docking studies revealed that the carboxylic group of the most active compounds is within hydrogen bonding distance of His-12, Lys-41 and His-119. (C) 2009 Elsevier Ltd. All rights reserved.