Specificity determinants of acylaminoacyl‐peptide hydrolase

  • Krishna R
  • Wold F
  • 5


    Mendeley users who have this article in their library.
  • 8


    Citations of this article.


In an attempt to explore how specific features of the substrate's primary structure may affect the activity of rabbit muscle acylaminoacyl-peptide hydrolase (EC, a number of acetylated peptides containing specific amino acid replacements in specific positions were prepared and compared as substrates for the hydrolase. The principal variants were D-Ala, Pro, and positive charges (His, Arg, Lys); in addition, the effect of the length of the peptide was also investigated in a less systematic manner. The substrates were either prepared by direct acetylation of peptides, by extension of the N-terminus with acetylamino acids or acetylpeptides, activated as N-hydroxysuccinimide esters, or by isolation of the N-terminal peptides from naturally occurring acetylated proteins. It was found that D-Ala on either side of the bond to be cleaved (positions 1 and 2) completely inhibited the enzymatic activity, whereas acetylated peptides with D-Ala in positions 3 or 4 were as good substrates as those containing L-Ala. Peptides with Pro in positions 2 were also inactive, and most of the peptides with Pro in the third position were very poor substrates; only the peptide Ac-AAP gave reasonably high activity (30% of Ac-AAA), which was reduced to 1-2% if additional residues were present at the C-terminus (Ac-AAPA, Ac-AAPAA). The presence of a positive charge in positions 2, 3, 4, 5, and 6 gave strong reduction in hydrolase activity varying with the charge's distance from the N-terminus from 0 to 15-20% of the rates obtained with the reference peptides without positive charges.

Author-supplied keywords

  • N‐terminal processing
  • acetylated N‐termini
  • acylaminoacyl‐peptide hydrolase
  • posttranslational modification
  • primary sequence specificity determinants

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document

Get full text


  • Radha G. Krishna

  • Finn Wold

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free