Some properties of an extracellular adenosine deaminase produced from Streptomyces sp. Y-256 were examined after 30-80% of ammoniumsulfate fractionation. The optimun pH and temperature for the stability of this enzyme were found to be near 7.0
and
40℃,
respectively. The eenzyme was stable in 0.05 M of potassium phosphate buffer. As results of examination for the enzyme activity to various pHs, the enzyme was generally highest in its activitynear pH 7.0 but inactivated completely near pH 4.5 and
pH 8.5
The enzyme activity to tempertures was hightly near 37℃ andcompletely disappeared near 60℃ Of metal ions used I mMof Mg2+ increased slightly the enzyme activity, but 1 mM of α,α'-dipyridyl, NaCN and ophenanthroline, including 10mM of
ethylenediaminetetraacetic acid, monoildoacetate, pentachlorophenol and p-chloromercuric benzoate completely inhibited the enzyme activity.
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