Purification and Characterization of Sarcosine Oxidase of Streptomyces Origin

Abstract

Sarcosine oxidase (EC 1.5.3.1) produced by Streptomyces sp. KB210-8SY was purified by ion exchange chromatography on DEAE-sepharose CL-6B, affinity chromatography on sarcosyl-AH-sepharose 4B and gel filtration on sephadex G-150 to electrophoretic homogeneity.
The molecular weight of the enzyme was estimated to be 44000 by sodium dodecyl sulfate (SDS) -polyacrylamide gel electrophoresis and gel filtration on Sephadex G-150. The enzyme showed the maximum activity at pH 8 and was stable at pH 7-9. In addition to sarcosine, the enzyme oxidized N-methyl-L-leucine, N-methyl-DL-alanine and N-methyl-DL-valine to lesser extents. The apparent K_m values for sarcosine, N-methyl-L-leucine, N-methyl-DL-alanine and N-methyl-DL-valine were 0.91, 0.58, 1.6 and 6.7 mM, respectively. The enzyme was inactivated by N-bromosuccinimide, hydroxylamine hydrochloride, SDS, Zn²⁺, Ni²⁺ and Hg²⁺ but not by ethylenediaminetetraacetate, p-chloromercuribenzoate or p-toluenesulfonyl chloride.
The taxonomic characteristics of strain KB210-8SY are closely related to those of Streptomyces flavovirens and S. misakiensis.