Dear Dr. Spagnol:
I recently finished a project for the analysis of glycoforms on a recombinant
lysosomal enzyme, alph-L-iduronidase, using lectin binding, HPLC, and MALDI-
TOFMS (mass spectrometry) prior to and after endo-glycosidase digestion. With
this protocol, I was able to detect phosphate on high mannose (Man-6-P). The
phosphate was confirmed by alkaline phosphatase cleavage. I believe SO4, which
happens to have identical mass as PO4 (~80 Da), could also be identified this
way (as well as any other methods available).
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* Ke-Wei Zhao, Ph.D. Phone: (310)825-8722 *
* Department of Biological Chemistry Fax: (310)206-5272 *
* UCLA School of Medicine, CHS 33-257 e-mail: kzhao at biovx1.biology.ucla.edu *
* Los Angeles, CA 90095-1737 *
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