Córdoba O L, Sánchez E I, Veerkamp J H, Santomé J A
Instituto de Química y Fisicoquímica Biológicas (UBA-CONICET), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Argentina.
Int J Biochem Cell Biol. 1998 Dec;30(12):1403-13. doi: 10.1016/s1357-2725(98)00085-5.
Five fatty-acid-binding proteins from the liver of the elephant fish (Callorhynchus callorhynchus), a chimaera fish that belongs--together with the elasmobranchs--to the ancient chondrichthyes class were isolated and characterized. The purification procedures for these proteins involved gel filtration, anion-exchange chromatography, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis as a last step. They were submitted to "in gel" tryptic or cyanogen bromide digestion and the resulting peptides were separated by high performance liquid chromatography and then sequenced by Edman degradation. According to their partial amino acid sequences, one of them presents the highest identity with fatty-acid-binding proteins from human and catfish liver, another three with those from mammalian heart or adipose tissue and the fifth with the mammalian intestinal fatty-acid-binding protein. The presence of various members of this protein family, as now found in elephant fish and previously in catfish (Rhamdia sapo) liver, does not occur in mammalian liver which express only one a characteristic fatty-acid-binding protein.
象鱼（Callorhynchus callorhynchus）属于与鲨类同属古代软骨鱼纲的银鲛目鱼类，从其肝脏中分离并鉴定出了五种脂肪酸结合蛋白。这些蛋白质的纯化过程包括凝胶过滤、阴离子交换色谱，最后一步是十二烷基硫酸钠-聚丙烯酰胺凝胶电泳。将它们进行“胶内”胰蛋白酶或溴化氰消化，所得肽段通过高效液相色谱分离，然后用埃德曼降解法测序。根据它们的部分氨基酸序列，其中一种与人类和鲶鱼肝脏中的脂肪酸结合蛋白具有最高的同源性，另外三种与哺乳动物心脏或脂肪组织中的脂肪酸结合蛋白同源，第五种与哺乳动物肠道脂肪酸结合蛋白同源。现在在象鱼以及之前在鲶鱼（Rhamdia sapo）肝脏中发现的这个蛋白质家族的各种成员，在仅表达一种特征性脂肪酸结合蛋白的哺乳动物肝脏中并不存在。
