Stability and Stabilization of Recombinant Peroxidase in Reversed Micelles

N. L. Klyachko,^1,2 Yu. K. Dulkis,¹ T. A. Sukhoruchenko,¹ and A. V. Levashov¹

¹Division of Chemical Enzymology, School of Chemistry, Lomonosov Moscow State University, Moscow, 119899 Russia; fax: (7-095) 939-34-29.

²To whom correspondence should be addressed.

Submitted December 9, 1996.

Stability of recombinant peroxidase lacking carbohydrate residues on the surface of the protein molecule has been characterized in reversed micelles of Aerosol OT in octane. The enzyme stability was found to depend on the surfactant hydration degree (w₀ = [H₂O]/[AOT]). Residual activity after 1 h incubation dropped to zero at w₀ = 7 but was 54% at w₀ = 25. However, the residual activity levels at all values of hydration degree were definitely low compared to that of glycosylated wild-type horseradish peroxidase. The stability of the enzyme apparently depends on the presence of carbohydrate residues. Stabilization of recombinant peroxidase in reversed micellar system involved sugar-containing co-surfactants such as Tweens and Spans is proposed. Addition of 1 mM Span 80 (1% relative to AOT concentration) increased the recombinant peroxidase stability up to that of wild-type peroxidase.

KEY WORDS: horseradish peroxidase, stability, glycoproteins, recombinant peroxidase, reversed micelles.

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