The first demonstration of a procaryotic glycosylasparaginase

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.