초록
Aeromonas, salmonicida YA7-625가 생산하는 chitinase는 $Hg^{2+}$에 의해 저해를 받았으나, $\beta$-mercaptoethanol 처리에 의해서 활성이 보호되었으며 Na-thiosulfate, ascorbic acid등의 환원제들과 sodium azide, p-CMB 등의 -SH 저해제에대하여 전혀 작용을 받지 않았으므로 본 효소의 활성중심에는 -SH가 없는 것으로 생각되었다. 또한 histidine, cysteine, tyrosine 및 trytophan에 작용하는 iodine에 의하여 저해를 받았으며 tryptophan에 대해 특이적으로 작용하는 N-bromosuccinimide에 의해 실활되는 것으로 보아 활성중심에 tryptophan, histidine 및 tyrosine 가 존재하는 것으로 생각되었다.
To investigate the characteristics of active sites of the chitinase isolated from AWOrnonus sulmonicidu YA7-625, effects of various chemicals un the enzyme activity were analyzed. $Hg^{2+}, Mn^[2+} \;and \; Cu^{2+}$ ' ions inhibited the activity of chitinase, while $Ca^{2+} , Zn^[2+} , Co^[2+} \; and\; Mg^[2+}$ ions at 1 mM stimulated enzyme activity. The chitinase was not inhibited by sulfhydryl ;gents, phenylglyoxal, and hydroxylamine, but was inhibited by iodine and N-bromosuccinimide. The $pK_{ps2} and pK_{ps2}$, values of chitinase were 4.04 a d 10.10, respectively. These results suggested that the chitinase from A~ronmzus salmonici& YA7-625 contains histidine, tyrosine. and tryptophan at the active center.