Мixed-ligand complexes of germanium – 3d-metal with 1-hydroxyethane-1,1-diphosphonic acid аnd 2,2′-bipyridine as modulators of Bacillus sp. IMV B-7883 elastase and fibrinogenase activity

Abstract

We have previously shown that Bacillus sp. IMV B-7883 exhibits both elastase and fibrinogenolytic activity. One of the approaches to enhance enzymatic activity is the use of coordination compounds capable to affect enzyme’s activity or synthesis. The purpose of this work was to study the effect of mixed-ligand complexes of Ge(IV) – Co(II) (Ni(II), Cu(II)) with 1-hydroxyethane-1,1-diphosphonic acid аnd 2,2′-bipyridine on the activity of elastase and fibrinogenase purified from Bacillus sp. IMV B-7883. Previously synthesized and characterized mixed-ligand complexes and enzymes purified from the supernatant of the bacterial culture liquid were used in the study. Elastase activity was determined colorimetrically with the use of Congo red, fibrinogenase activity was estimated by fibrinogen hydrolysis measured by absorption at 275 nm. It was shown that complexes 1 (C132H164Co4Ge6N24O68P12) and 2 (C132H148Ge6N24Ni4O60P12) inhibited activity of Bacillus sp. IMV B-7883 elastase by 54 and 71% respectively, while complex 3 (C92H128Cu4Ge6N16O63P12) enhanced it by 30%. Stimulating effect of all three complexes on fibrinogenase activity was revealed. Thus, complex 1 and 2 activated the enzyme by more than 50% and complex 1 – by 19%. The data obtained indicate a complex mechanism of the studied complexes influence on enzymatic activity depending on both their composition and structure. Keywords: 1-hydroxyethane-1‚1-diphosphonic acid, 2‚2′-bipyridine, Bacillus sp. IMV B-7883, elastase, fibrinogenase, germanium – 3d-metal, mixed-ligand complexes