Division of Clinical Sciences, Wadsworth Center for Laboratories and Research, New York State Department of Health, Albany.
Glycosylasparaginase was purified to near homogeneity from intracellular lysates of Flavobacterium meningosepticum. The enzyme is a heterodimer with an estimated molecular weight of 38 kDa and consists of one alpha-subunit (18 kDa) and one beta-subunit (16 kDa). The beta-subunit of the Flavobacterium enzyme has a direct evolutionary relationship to the beta-subunit of mammalian glycosylasparaginases as evidenced by: (1) strong cross-reactivity with antibodies made to the denatured rat beta-subunit, (2) a high degree of homology with the amino-terminus of the corresponding eukaryotic enzymes, and (3) irreversible inactivation with 5-diazo-4-oxo-L-norvaline, a reagent known to react with the catalytic amino-terminal threonine residue on the beta-subunit of a mammalian glycosylasparaginase.