Eschertchta coli K-12 JH318주로부터 초음파, $(NH_4)_2SO_4$침전, DEAE-cellulose 크로마토 그래피, Sephadex gel 크로마토 그래피에 의하여 23배 정제된 chorismate mutase(P)-prephenate dehydratase를 분리하였다. single bifunctional enzyme인 이 효소는 carboxyl잔기를 갖는 glutamic acid와 aspartic acid 그리고 citric acid에 의해 20%의 활성이 저해를 받았으며 1 mM의 페닐알라닌에 의해 부분정제된 경우 97%가 저해되었다. 타이로신의 경우는 전혀 저해되지 않았지만 crude extract의 경우는 3mM의 타이로신 농도하에서 chorismate mutase가 28%, prephenate dehydratase가 16%의 활성이 증가 되었다. 대다수의 금속원소에 의해서는 효소활성이 저해되었지만 알칼리 토금속 그룹 특히 1 mM 마그네슘 이온에 의해 98% 활성이 증가되었다.
Chorismate mutase(P)-prephenate dehydratase from Escherichia coli K-12 JH318 strain was purified 23-fold by sonic extraction, $(NH_4)_2SO_4$ precipitation, DEAE-Cellulose and Sephedex gel chromatography. Single bi functional enzyme, chorismate mutase(P)-prephenate dehydratase was approximately 15% inhibited by glutamic acid, aspartic acid, citrate which have carboxyl group. The activity of prephenate dehydratase was approximately 97% inhibited by 1 mM of phenylalanine in partially purified enzyme and was more weakly inhibited in crude. The chorismate mutase(P) -prephenate dehydratase was insensitive to feed back regulation by tyrosine in partially purified enzyme, but chorismate mutase was 28% activated by 1 mM of tyrosine and prephenate dehydratase was 16% activated in crude extracts. Strong inhibition of prephenate dehydratase was observed with the divalent metal ions, Cu, Zn and Hg, but this enzyme was activated by group IIa in periodic table including Mg, Ca, Ba, specially 98% activated by Mg ion.
