Graham L D, Underwood P A
Cooperative Research Centre for Cardiac Technology, NSW, Australia.
Biochem Mol Biol Int. 1996 Jun;39(3):563-71. doi: 10.1080/15216549600201621.
The intracellular heparanases from mouse macrophage and melanoma cells are very similar in terms of their size (60-80 kDa), pI (5.3-4.1), pH optimum (< or = 5.5), and interactions with heparin. These proteins are therefore likely to be identical, suggesting that tumour and blood cells utilise the same heparanase enzyme. The human platelet enzyme is similar to the mouse enzymes in terms of pH optimum (< or = 5.5) and pI value (5.3-4.8), but appears to be smaller in size (40-60 kDa). It also seems to differ from the mouse enzymes in aspects of its surface charge, and in its interactions with heparin. There was no indication that proteolysis was of significance for the enzymes, nor that they contained any sialic acid residues.
来自小鼠巨噬细胞和黑色素瘤细胞的细胞内乙酰肝素酶在大小（60 - 80 kDa）、pI（5.3 - 4.1）、最适pH（≤5.5）以及与肝素的相互作用方面非常相似。因此，这些蛋白质可能是相同的，这表明肿瘤细胞和血细胞利用的是同一种乙酰肝素酶。人血小板酶在最适pH（≤5.5）和pI值（5.3 - 4.8）方面与小鼠酶相似，但在大小上似乎较小（40 - 60 kDa）。在其表面电荷以及与肝素的相互作用方面，它似乎也与小鼠酶不同。没有迹象表明蛋白水解对这些酶具有重要意义，也没有迹象表明它们含有任何唾液酸残基。
