Koyama I, Miura M, Matsuzaki H, Sakagishi Y, Komoda T
J Chromatogr. 1987 Jan 23;413:65-78. doi: 10.1016/0378-4347(87)80214-1.
The sugar-chain heterogeneity of alkaline phosphatases (ALPs) from various human organs was investigated by using the serial lectin affinity technique. This technique revealed a possible structure of the sugar chain(s) of ALP isozymes and clarified a difference in affinity on the lectin column not only among three genetically different isozymes (liver/bone/kidney, intestinal and placental types) but also among liver, bone, and kidney ALPs. Lectin-binding profiles of ALPs in these human organs closely resembled those in the corresponding organs of the rat, as reported previously, suggesting that heterogeneities in sugar chains of ALPs have a specificity for the respective organs rather than being species-specific. Lectin-binding profiles of tumour-produced placental and liver ALPs were significantly different from those of ALPs in the respective normal organs. However, the two altered ALPs exhibited similar lectin-binding affinities. Isoelectric focusing analysis showed essentially no difference in protein charge between the normal and tumor-produced ALPs. Moreover, tumour-produced ALPs had the same N-terminal amino acid sequence and peptide mapping as normal ALPs. From these results, it is possible to suggest that organ-specific sugar chains in ALP isozymes are changed into those peculiar to tumours in association with malignant transformation.
采用系列凝集素亲和技术研究了来自人体不同器官的碱性磷酸酶（ALP）的糖链异质性。该技术揭示了ALP同工酶糖链的可能结构，并阐明了不仅在三种基因不同的同工酶（肝/骨/肾型、肠型和胎盘型）之间，而且在肝、骨和肾ALP之间，凝集素柱上的亲和力差异。如先前报道，这些人体器官中ALP的凝集素结合谱与大鼠相应器官中的凝集素结合谱非常相似，这表明ALP糖链的异质性对各个器官具有特异性，而非物种特异性。肿瘤产生的胎盘型和肝型ALP的凝集素结合谱与相应正常器官中的ALP显著不同。然而，这两种改变的ALP表现出相似的凝集素结合亲和力。等电聚焦分析表明，正常和肿瘤产生的ALP之间蛋白质电荷基本没有差异。此外，肿瘤产生的ALP与正常ALP具有相同的N端氨基酸序列和肽图。从这些结果可以推测，ALP同工酶中器官特异性糖链在恶性转化过程中会转变为肿瘤特有的糖链。
