Modulation of Ligand Binding Affinity of Tumorigenic Carbonic Anhydrase XII upon Interaction with Cationic CdTe Quantum Dots.

ABSTRACT: The structural data of tumorigenic carbonic anhydrase (CA) XII revealed that the enzyme surface opposite to the active site pocket was negatively charged, and thus it had potential to interact with the positively charged surfaces. We investigated the influence of cationic CdTe quantum dots on the catalytic and ligand binding properties of the enzyme. Although cationic quantum dots interacted with CAXII (with a K(d) value of 2.1 μM), they did not impair the enzyme's catalytic activity, suggesting that the accessibility of the enzyme's active site remained unaffected by the above interaction. When CAXII bound dansylamide (serving as a fluorescence probe as well as a potent inhibitor of the enzyme) was titrated with cationic quantum dots, the fluorescence spectral profiles revealed a marked t

SUBMITTER: Manokaran S 

PROVIDER: S-EPMC2759756 | biostudies-literature | 2008 Dec

REPOSITORIES: biostudies-literature