Kessel D, Chou T H, Allen J
Eur J Biochem. 1978 Jan 16;82(2):535-41. doi: 10.1111/j.1432-1033.1978.tb12048.x.
Some properties of sialyltransferase activity in plasma and lymphocytes from patients with chronic lymphocytic leukemia were compared. Three distinct enzyme fractions were identified in plasma: (1) cation independent, irreversibly bound to agarose; (2) cation dependent, weakly bound to agarose; (3) strongly bound to agarose, lost upon dialysis. Lowering of the peripheral lymphocyte count by leukapheresis markedly decreased the level of serum sialyltransferase, suggesting the circulating lymphocyte is a source of the serum enzyme. The enzyme solubilized by detergent from lymphocytes showed a substantially lower Km for CMP-sialic acid than did the serum enzyme, was less sensitive to several inhibitors, was not irreversible bound to Agarose, and had a substantial cation requirement. The enzyme solubilized from the lymphocyte therefore generally resembles fraction 2 of serum.
比较了慢性淋巴细胞白血病患者血浆和淋巴细胞中唾液酸转移酶活性的一些特性。在血浆中鉴定出三种不同的酶组分：(1) 不依赖阳离子，不可逆地结合于琼脂糖；(2) 依赖阳离子，弱结合于琼脂糖；(3) 强结合于琼脂糖，透析后丧失。通过白细胞分离术降低外周淋巴细胞计数可显著降低血清唾液酸转移酶水平，提示循环淋巴细胞是血清酶的来源。用去污剂从淋巴细胞中溶解的酶对CMP-唾液酸的Km值明显低于血清酶，对几种抑制剂的敏感性较低，不与琼脂糖不可逆结合，且对阳离子有大量需求。因此，从淋巴细胞中溶解的酶总体上类似于血清的组分2。
