alpha-N-Acetylgalactosaminidase from Marine Bacterium Arenibacter latericius KMM 426^T Removing Blood Type Specificity of A-Erythrocytes

I. Yu. Bakunina^1*, R. A. Kuhlmann², L. M. Likhosherstov³, M. D. Martynova³, O. I. Nedashkovskaya¹, V. V. Mikhailov¹, and L. A. Elyakova¹

¹Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Sciences, pr. 100-letiya Vladivostoka 159, Vladivostok, 690022 Russia; fax: (4232) 314-050; E-mail: piboc@stl.ru

²Hematology Research Center, Russian Academy of Medical Sciences, Novo-Zykovskii pr. 4, Moscow, 125167 Russia

³Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky pr. 47, Moscow, 119991 Russia

^* To whom correspondence should be addressed.

Received May 23, 2001; Revision received July 1, 2001

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An alpha-N-acetylgalactosaminidase IV able to remove blood type specificity of human A(II)-erythrocytes and not effecting B(III)-erythrocytes was isolated from the marine bacterium Arenibacter latericius KMM 426^T. The alpha-N-acetylgalactosaminidase IV preparation exhibits high activity during inhibition of hemagglutination with blood group substance A containing determinants analogous to A-erythrocytes. The enzyme has a pH optimum from 7.0 to 8.0 and completely retains its activity during 30-min heating at 50°C and for a week at 20°C. The enzyme can be stored under the sterile conditions for any length of time at 4°C, but it does not withstand freezing. The alpha-N-acetylgalactosaminidase is resistant to NaCl; for p-nitrophenyl-alpha-N-acetyl-D-galactosaminide, the K_m is 0.38 mM. The molecular mass of the enzyme determined by gel filtration is 84 kD.

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KEY WORDS: alpha-N-acetylgalactosaminidase, marine bacteria Arenibacter latericius, transformation of erythrocytes

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