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PubMed · 9196541

Basic aminopeptidase from rabbit kidney: purification and partial characterization.

S M Oliveira·J O Freitas Júnior·K B Alves
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Abstract

The aminopeptidase activity of a homogenate of rabbit kidney treated with Triton X-100 was measured using L-aminoacyl-2-naphthylamides (AA-NA). After gradient elution ion-exchange chromatography, four peaks of aminopeptidase activity were eluted. The enzyme eluted at 450 microS containing 33.5% of the activity towards Arg-NA was applied to a Superdex 75 column and presented only one protein band on 10% SDS-polyacrylamide gel electrophoresis. This enzyme has an apparent molecular mass of 78 kDa, is five-fold activated by 0.15 M NaCl and the highest Vmax/KM ratio was obtained with Arg-NA. Enzyme activity was inhibited 100% by 0.13 mM sodium p-hydroxymercuribenzoate, 20% by 0.75 mM EDTA and 100% by 0.66 mM o-phenanthroline. Puromycin and bestatin behaved like competitive inhibitors with a Ki of 0.60 mM and 5.0 microM and 5.0 microM, respectively.

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2-NaphthylamineAminopeptidasesAnimalsKidneyRabbitsJournal ArticleResearch Support, Non-U.S. Gov't

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S M Oliveira, J O Freitas Júnior, K B Alves. 1996. Basic aminopeptidase from rabbit kidney: purification and partial characterization.. https://pubmed.ncbi.nlm.nih.gov/9196541/

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