An activated by cobalt alkaline aminopeptidase from Bacillus mycoides.
An intracellular arginine--specific aminopeptidase synthesized by Bacillus mycoides was purified and characterized. The purification procedure for studied aminopeptidase consisted of ammonium sulphate precipitation and three chromatographic steps: anion exchange chromatography and gel permeation chromatography. A molecular weight of -50 kDa was estimated for the aminopeptidase by gel permeation chromatography and SDS-PAGE. The optimal activity of the enzyme on arginyl-beta-naphthylamide as a substrate was at 37 degrees C and pH 9.0. The enzyme showed maximum specificity for basic amino acids: such as Arg and Lys but was also able to hydrolyze aromatic amino acids: Trp, Tyr, and Phe. Co2+ ions activated the enzyme, while Zn2+, Cu2+, Hg2+ and Mn2+ inhibited it. The enzyme is a metalloaminopeptidase whose activity is inhibited by typical metalloaminopeptidase inhibitors: EDTA and 1,10-phenanthroline. Analysis of fragments of the amino acid sequence of the purified enzyme demonstrated high similarity to AmpS of Bacillus cereus and AP II of B. thuringensis.
Department of Biochemistry, Warsaw University of Life Science, 02-776 Warsaw, Poland. urszula_jankiewicz@sggw.pl
U
U
Jankiewicz
A
A
Wnuk
D000595:Amino Acid Sequence; D000596:Amino Acids / Q000737:chemistry; D000626:Aminopeptidases / Q000737:chemistry / Q000378:metabolism*; D001407:Bacillus / Q000201:enzymology*; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism*; D002413:Cations, Divalent; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D003035:Cobalt / Q000378:metabolism*; D004492:Edetic Acid / Q000737:chemistry; D004591:Electrophoresis, Polyacrylamide Gel; D004789:Enzyme Activation; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009281:Naphthalenes / Q000378:metabolism*; D010618:Phenanthrolines / Q000737:chemistry; D016415:Sequence Alignment; D012689:Sequence Homology, Nucleic Acid; D013379:Substrate Specificity; D013696:Temperature
D000596:Amino Acids; D001426:Bacterial Proteins; D002413:Cations, Divalent; D009281:Naphthalenes; D010618:Phenanthrolines; D003035:Cobalt; D004492:Edetic Acid; D000626:Aminopeptidases; C025205:1,10-phenanthroline