FLUORESCENCE AND UV-VIS SPECTRAL ANALYSIS OF THE INTERACTION OF ADENOSINE DEAMINASE AND COMPOUND D011_186

Abstract

Adenosine deaminase (ADA) is an enzyme important in mammalian purine metabolism and in maintenance of the immune system. Its activity increases in pathological conditions, resulting in decrease in the concentration of anti-inflammatory adenosine, with aggrаvation of inflammation. Therefore, the discovery and development of ADA inhibitors represent an actual biochemical and pharmacological task. We tested approximately 100 new synthesized aniline and piperazine derivatives for their ADA inhibitory activity. The present study describes the inhibition of ADA by one of the aniline derivatives tested, D011_186. The compound exhibited potent inhibitory activity with an IC₅₀ value of 40±1.1 µg/mL. The interaction between the ADA and D011_186 was investigated using UV-Vis and fluorescence spectroscopy techniques. Differential UV-Vis spectroscopy analysis of the ADA-compound interaction revealed no significant difference between the optical absorption of their mixture relative to the sum of their individual spectra. Next, 2D and 3D fluorescence spectroscopy methods were applied to assess ADA-compound interaction. The individual fluorescence spectra of ADA and compound were compared with the spectrum of their mixture, however, no changes in the recorded fluorescence spectra reflecting their interaction were detected. Thus, although the compound D011_186 inhibits ADA activity it is not accompanied by a change in the orbitals of their optical electrons.