Purification and properties of neuraminidase from the culture medium of Bacteroides loescheii.

Neuraminidase was purified from the culture medium of Bacteroides loescheii ATCC 15930 by ultrafiltration followed by a DEAE-Sephacel anion exchange chromatography, fast-protein liquid chromatography using Mono P column and high-performance liquid chromatography using a Shim-pack Diol-300 column. The molecular weight of the purified enzyme was measured to be approximately 87 kDa and the optimal pH was at 4.8. Although the enzyme was able to hydrolyze the substrates with alpha,2-3, alpha,2-6, and alpha,2-8 linkages of N-acetylneuraminic acid, the rate of hydrolysis of N-acetylneuraminosyl-alpha,2-3-lactose was greater than that of the alpha,2-6-isomer.