| Autor: |
Wei Zhang, Czupryn, Marta J., Boyle Jr., Philip T., Amari, John |
| Předmět: |
|
| Zdroj: |
Pharmaceutical Research; Aug2002, Vol. 19 Issue 8, p1223, 9p, 1 Black and White Photograph, 1 Diagram, 1 Chart, 20 Graphs |
| Abstrakt: |
Purpose. The aim of this study was to investigate asparagine (Asn) deamidation and aspartate (Asp) isomerization and to measure the content of isoaspartate (isoAsp) in recombinant human interleukin-11 (rhIL-11). Methods. The rhIL-11 control and heat stressed samples were characterized with trypsin and endoproteinase Asp-N peptide mapping, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDSPAGE), reversed-phase high performance liquid chromatography (RP-HPLC), electrospray ionization mass spectrometry (ESI MS) and capillary electrophoresis (CE). The total isoAsp content and bioactivity were also assessed. Results. Stress of rhIL11 at 30°C for 6 weeks in liquid resulted in significant isomerization of Asp[sup 45] and Asp[sup 47]. Isomerization of Asp[sup 51] and deamidation of Asn[sup 49] were also detected at low levels. The stressed rhIL-11 molecule contained 0.3 mol of isoAsp per mol of protein, compared to only 0.007 mol/mol of protein in the control. Conclusions. Asp and Asn residues, located in a loop structure of rhIL-11, undergo isoAsp formation under stressed conditions. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
|
Full text from SpringerLink