Slater A C, Jones-Mortimer M C, Kornberg H L
Biochim Biophys Acta. 1981 Aug 20;646(2):365-7. doi: 10.1016/0005-2736(81)90346-1.
L-Sorbose is phosphorylated by Escherichia coli by two distinct Enzymes II of the phosphoenolpyruvate-dependent phosphotransferase system. The glucose Enzyme II (specified by the gene ptsG) phosphorylates L-sorbose with an apparent Km of 0.08 +/- 0.03 mM and V of 31.8 +/- 3.5 nmol . mg-1 . min-1 whilst the fructose Enzyme II (specified by the gene ptsF) phosphorylates it with an apparent Km of 28.9 +/- 2.7 mM and V of 20.2 +/- 0.8 nmol . mg-1 . min-1. L-Sorbose induces neither of these Enzymes II, but sorbose inhibits the growth of strains expressing either of these functions constitutively. Mutants that have lost their sensitivity to L-sorbose are found to have lost either the glucose or the fructose phosphotransferase Enzyme II.U
L-山梨糖可被大肠杆菌通过磷酸烯醇丙酮酸依赖性磷酸转移酶系统的两种不同的酶II进行磷酸化。葡萄糖酶II（由ptsG基因指定）将L-山梨糖磷酸化，其表观Km为0.08±0.03 mM，V为31.8±3.5 nmol·mg⁻¹·min⁻¹，而果糖酶II（由ptsF基因指定）将其磷酸化，表观Km为28.9±2.7 mM，V为20.2±0.8 nmol·mg⁻¹·min⁻¹。L-山梨糖不会诱导这两种酶II，但山梨糖会抑制组成型表达这两种功能之一的菌株的生长。发现对L-山梨糖失去敏感性的突变体已失去葡萄糖或果糖磷酸转移酶酶II。
