Malloy M H, Rassin D K, Gaull G E
Am J Clin Nutr. 1981 Dec;34(12):2619-21. doi: 10.1093/ajcn/34.12.2619.
Using a method developed to measure plasma protein-bound 1/2-cystine, we have observed that the metabolic state can affect the distribution of plasma cyst(e)ine between the bound and the free form. In five patients with homocyst(e)inemia, 1/2-homocystine was found to have replaced virtually all the cysteine normally present on sulfhydryl-binding sites of plasma proteins. The majority of the cyst(e)ine measured in the plasma of these patients (6.9 +/- 2.4 mumol/dl, mean +/- SD) was present in the form of a mixed disulfide with 1/2-homocystine (5.4 +/- 0.9 mumol/dl) rather than being free in the plasma or bound to plasma proteins.
运用一种专门开发用于测量血浆蛋白结合型半胱氨酸的方法，我们观察到代谢状态会影响血浆中胱氨酸在结合型和游离型之间的分布。在5名同型胱氨酸血症患者中，发现半胱氨酸几乎取代了血浆蛋白巯基结合位点上正常存在的所有半胱氨酸。这些患者血浆中测得的大部分胱氨酸（6.9±2.4μmol/dl，平均值±标准差）以与半胱氨酸形成的混合二硫键形式存在（5.4±0.9μmol/dl），而非游离于血浆中或与血浆蛋白结合。
