title: Proteins from Erwinia asparaginase Erwinase ® and E. coli asparaginase 2 MEDAC ® for treatment of human leukemia, show a multitude of modifications for which the consequences are completely unclear.
abstract: L-Asparaginase from Erwinia chrysanthemi (ASPG_ERWCH; UniProtKB accession number P06608 (Erwinase(®))) and L-asparaginase 2 from Escherichia coli (ASPG2_ECOLI; UniProtKB accession number P00805 (Medac(®))), both L-asparagine amidohydrolases, are widely used for the treatment of acute lymphoblastic leukemia. A series of serious side effects have been reported and this warrants studies into the protein chemistry of the medical products sold. Mass spectrometry (MS) data on ASPG_ERWCH and ASPG2_ECOLI have not been published so far and herein a gel-based proteomics study was performed to provide information about sequence and modifications of the commercially available medical products. ASPG_ERWCH and ASPG2_ECOLI were applied onto two-dimensional gel electrophoresis, spots were in-gel digested with several proteases and resulting peptides and protein modifications were analysed by nano-ESI-LC-MS/MS. Four spots were observed for ASPG_ERWCH, six spots were observed for ASPG2_ECOLI and the identified proteins showed high sequence coverage without sequence conflicts. Several protein modifications including technical and posttranslational modifications were demonstrated. Protein modifications are known to change physicochemical, immunochemical, biological and pharmacological properties and results from this work may challenge re-designing of the product including possible removal of the modifications by the manufacturer because it is not known whether they are contributing to the serious adverse effects of the protein drug.
authors.affiliation: Department of Pediatrics, Medical University of Vienna, Vienna, Austria.
authors.forename: Narkhyun
authors.initials: N
authors.lastname: Bae
authors.forename: Arnold
authors.initials: A
authors.lastname: Pollak
authors.forename: Gert
authors.initials: G
authors.lastname: Lubec
mesh_terms: D000595:Amino Acid Sequence; D000970:Antineoplastic Agents / Q000737:chemistry / Q000378:metabolism; D001215:Asparaginase / Q000737:chemistry* / Q000378:metabolism*; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism; D015180:Electrophoresis, Gel, Two-Dimensional; D004885:Erwinia / Q000201:enzymology*; D004926:Escherichia coli / Q000201:enzymology*; D006031:Glycosylation; D006801:Humans; D008745:Methylation; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000188:drug therapy* / Q000378:metabolism; D011499:Protein Processing, Post-Translational
chemical_list: D000970:Antineoplastic Agents; D001426:Bacterial Proteins; D010446:Peptide Fragments; D001215:Asparaginase