Fykse E M, Sletten K, Husby G, Cornwell G G
Department of Biochemistry, University of Oslo, Blindern, Norway.
Biochem J. 1988 Dec 15;256(3):973-80. doi: 10.1042/bj2560973.
The primary structure of the variable region of an amyloid-fibril protein GIL of immunoglobulin lambda-light-chain origin (AL) was determined. The AL protein obtained from the fibrils in the spleen of a 54-year-old man with primary systemic amyloidosis could be assigned to subgroup IV of the lambda variable-region sequence. About 50% of the protein was found to be truncated in the N-terminus and lacked the first six amino acid residues. The polypeptides consisted of about 146 amino acid residues and contained traces of carbohydrate. An acceptor site for N-glycosylation was found in positions 90-93, but no glycopeptide could be isolated. Comparison of the amino acid sequence of AL protein GIL with that of the only Bence-Jones protein of subgroup IV previously studied revealed a sequence homology of 89%. A similar comparison made with other AL proteins gave sequence homologies below 66%.
确定了源自免疫球蛋白λ轻链的淀粉样纤维蛋白GIL（AL）可变区的一级结构。从一名54岁原发性系统性淀粉样变性男性患者脾脏中的纤维中获得的AL蛋白可归为λ可变区序列的IV亚组。发现约50%的蛋白在N端被截断，缺少前六个氨基酸残基。这些多肽由约146个氨基酸残基组成，并含有微量碳水化合物。在第90 - 93位发现了一个N-糖基化的受体位点，但未分离到糖肽。将AL蛋白GIL的氨基酸序列与之前研究的IV亚组中唯一的本-周蛋白的氨基酸序列进行比较，发现序列同源性为89%。与其他AL蛋白进行的类似比较给出的序列同源性低于66%。
