Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
Biochem J. 2002 May 15;364(Pt 1):129-36.

Isoaspartyl dipeptidase activity of plant-type asparaginases.

Author information

  • 1Institut für Biologie, Humboldt-Universität zu Berlin, Chausseestr. 117, D-10115 Berlin, Germany.

Abstract

Recombinant plant-type asparaginases from the cyanobacteria Synechocystis sp. PCC (Pasteur culture collection) 6803 and Anabaena sp. PCC 7120, from Escherichia coli and from the plant Arabidopsis thaliana were expressed in E. coli with either an N-terminal or a C-terminal His tag, and purified. Although each of the four enzymes is encoded by a single gene, their mature forms consist of two protein subunits that are generated by autoproteolytic cleavage of the primary translation products at the Gly-Thr bond within the sequence GTI/VG. The enzymes not only deamidated asparagine but also hydrolysed a range of isoaspartyl dipeptides. As various isoaspartyl peptides are known to arise from proteolytic degradation of post-translationally altered proteins containing isoaspartyl residues, and from depolymerization of the cyanobacterial reserve polymer multi-L-arginyl-poly-L-aspartic acid (cyanophycin), plant-type asparaginases may not only function in asparagine catabolism but also in the final steps of protein and cyanophycin degradation. The properties of these enzymes are compared with those of the sequence-related glycosylasparaginases.

PMID:
11988085
[PubMed - indexed for MEDLINE]
PMCID:
PMC1222554
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Icon for Portland Press Icon for PubMed Central
    Loading ...
    Write to the Help Desk