Hassan H F, Mottram J C, Coombs G H
Comp Biochem Physiol B. 1985;81(4):1037-40. doi: 10.1016/0305-0491(85)90110-5.
Leishmania mexicana mexicana cultured promastigotes were fractionated by isopycnic centrifugation on linear sucrose gradients. Guanine, hypoxanthine and xanthine phosphoribosyltransferase activities were found to be associated with glycosomes, whereas adenine phosphoribosyltransferase was cytosolic. 3'- and 5'-nucleotidases and IMP dehydrogenase were shown to be particulate, the former two possibly being associated with the plasma membrane, IMP dehydrogenase with the endoplasmic reticulum. Nucleosidases and deaminases were found to be cytosolic. The results demonstrate that intracellular separation of enzymes could play a part in the regulation of the parasite's purine metabolism.
墨西哥利什曼原虫培养的前鞭毛体通过在线性蔗糖梯度上进行等密度离心进行分级分离。发现鸟嘌呤、次黄嘌呤和黄嘌呤磷酸核糖基转移酶活性与糖体相关，而腺嘌呤磷酸核糖基转移酶存在于胞质溶胶中。3'-和5'-核苷酸酶以及肌苷酸脱氢酶显示为颗粒状，前两者可能与质膜相关，肌苷酸脱氢酶与内质网相关。核苷酶和脱氨酶存在于胞质溶胶中。结果表明，酶的细胞内分离可能在寄生虫嘌呤代谢的调节中起作用。
