Streptonyces sp. (YS-40) 가 생산하는 penicillinase의 효소학적 성질을 조사한 결과는 다음과 같다. 본 효소의 작용 적용온도는 45$^{circ}C$이며 최적pH는 5.0부근이었다. 열처리에 대해서는37$^{circ}C$에서도 불안정하였으며 6$0^{circ}C$와 8$0^{circ}C$에서 60분간 처리했을 때 각각 60%, 80%가 실활되었으나 안정 pH범위는 4.5~8.5로서 비교적 넓었다. 금속 ion의 농도가 $10^{-3}$M로 반응액에 첨가 되었을 때 Cu$^{＋＋}$의 경우 25%정도 실활시켰으며 2 $ imes$$10^{-3}$M에서는 50% 정도 실활시켰다. SDS에 의해서 강하게 저해되었으며 EDTA, sodium fluoride 에 의해서 강하게 저해되었으나 MIA, L-cystine, urea에 의해서는 저해를 받지 않았다.
A strain of Streptomyces sp. (YS-40) which was able to produce penicillinase, was isolated from soil and the enzymatic characteristics of this enzyme were investigated. The crude enzyme was obtained with the fractionation by 80 % cold acetone. The optimal temperature and pH of this enzyme was 45$^{circ}C$ and 5.0 respectively. The stable pH range of the enzyme was between pH 5.5 and 8.0 at 37$^{circ}C$. By heat treatment at 6$0^{circ}C$ and 8$0^{circ}C$ for 10 min, the remained relative activities were about 50%, 30% respectively. The activity of the enzyme was inhibited by Cu$^{＋＋}$, $_Mn^{＋＋}$, Zn$^{＋＋}$ but Co$^{＋＋}$, Li$^{＋＋}$, $Ca^{＋＋}$, $Mg^{＋＋}$ $Ba^{＋＋}$ did not affect. Among 11 chemical reagents, ethylenedi aminetetra-acetic acid disodium salt (EDTA-2Na), sodium dodecyl sulfate (SDS) and sodium fluoride inhibited the enzyme activity.
