de Ruiter H, Kollöffel C
Botanical Laboratory, University of Utrecht, Utrecht, The Netherlands.
Plant Physiol. 1985 Mar;77(3):695-9. doi: 10.1104/pp.77.3.695.
Some properties of ornithine carbamoyltransferase from chloroplasts isolated from leaves of Pisum sativum L. (cv Marzia) were compared with those of the enzyme partially purified (316-fold) from shoots of seedlings after 3 weeks of cultivation.Both preparations showed a pH optimum at pH 8.3 and had the same affinity to ornithine (K(m) = 1.2 millimolar) as well as to carbamoyl phosphate (K(m) = 0.2 millimolar). The approximate molecular weight determined by gel sieving was 77,600.A desalted ammonium sulfate precipitate from 14-day seedlings (inclusive roots and senescing cotyledons) was applied on a column of anion exchanger. The elution pattern showed one peak of ornithine carbamoyl-transferase activity. This elution pattern was the same as observed for the enzyme from chloroplasts.The results suggest the presence of one form of ornithine carbamoyl-transferase in pea seedlings.
将从豌豆(品种Marzia)叶片中分离出的叶绿体鸟氨酸氨甲酰基转移酶的一些特性,与培养3周后的幼苗茎中部分纯化(316倍)的该酶的特性进行了比较。两种制剂的最适pH均为8.3,对鸟氨酸(K(m)=1.2毫摩尔)和氨甲酰磷酸(K(m)=0.2毫摩尔)具有相同的亲和力。通过凝胶筛分测定的近似分子量为77,600。将14天龄幼苗(包括根和衰老子叶)的脱盐硫酸铵沉淀物应用于阴离子交换柱。洗脱图谱显示出一个鸟氨酸氨甲酰基转移酶活性峰。该洗脱图谱与叶绿体酶的洗脱图谱相同。结果表明豌豆幼苗中存在一种形式的鸟氨酸氨甲酰基转移酶。