title: [THE EFFECT OF METAL IONES AND SPECIFIC CHEMICAL REAGENTS ON THE ACTIVITY OF ASPERGILLUS FLAVUS VAR. ORYZAE AND BACILLUS SUBTILIS α-AMYLASES].
abstract: The effect of cations and anions on the activity of Aspergillus flavus var. oryzae and Bacillus subtilis α-amylases showed that the tested enzymes are sensitive to most of cations and resistant to anions. The most significant inhibitory effects on the activity of A. flavus var. oryzae α-amylase have been demonstrated by Al3+ and Fe3+ ions, while on the activity of B. subtilis α-amylase - Hg2+, Cu2+ and Fe3+ ions. Inactivation of A. flavus var. oryzae and B. subtilis α-amylases in the presence of EGTA is indicated on the presence within their structure of metal ions. An important role in the enzymatic catalysis of both enzymes play carboxyl groups as evidenced by their inhibition of 1-[3-(dimethylamino)propyl]-3-ethylcarbodiimide methiodide. Inhibition of B. subtilis α-amylase by p-chloromercuribenzoate, N-ethylmaleimide and sodium sulfite is indicated on the probable involvement of the sulfhydryl groups in the functioning of the enzyme. Unlike most studied glycosidases the tested enzymes do not contain histidine imidazole group in the active center.
authors.forename: K V
authors.initials: KV
authors.lastname: Avdiyuk
authors.forename: L D
authors.initials: LD
authors.lastname: Varbanets
mesh_terms: D000535:Aluminum / Q000737:chemistry; D001231:Aspergillus flavus / Q000737:chemistry* / Q000201:enzymology; D001412:Bacillus subtilis / Q000737:chemistry* / Q000201:enzymology; D001426:Bacterial Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000302:isolation & purification; D055162:Biocatalysis; D002234:Carbodiimides / Q000737:chemistry; D020134:Catalytic Domain; D002412:Cations; D003300:Copper / Q000737:chemistry; D004533:Egtazic Acid / Q000737:chemistry; D057075:Enzyme Assays; D005033:Ethylmaleimide / Q000737:chemistry; D005656:Fungal Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000302:isolation & purification; D007501:Iron / Q000737:chemistry; D007700:Kinetics; D008628:Mercury / Q000737:chemistry; D013447:Sulfites / Q000737:chemistry; D000516:alpha-Amylases / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000302:isolation & purification; D020245:p-Chloromercuribenzoic Acid / Q000737:chemistry
chemical_list: D001426:Bacterial Proteins; D002234:Carbodiimides; D002412:Cations; D005656:Fungal Proteins; D013447:Sulfites; D004533:Egtazic Acid; D020245:p-Chloromercuribenzoic Acid; D003300:Copper; D000535:Aluminum; D007501:Iron; D000516:alpha-Amylases; D008628:Mercury; D005033:Ethylmaleimide; C025026:sodium sulfite