Duranti M, Horstmann C, Gilroy J, Croy R R
Dipartimento di Scienze Molecolari Agroalimentari, Università Statale di Milano, Italy.
J Protein Chem. 1995 Feb;14(2):107-10. doi: 10.1007/BF01888368.
Ion exchange-HPLC under denaturing conditions was used to purify to homogeneity the major M(r) 44,000 alpha subunit of lupin seed (Lupinus albus, L.) 11S storage globulin (legumin). The carboxymethylated subunit was digested with trypsin and the peptide fragments separated by reverse phase HPLC. Only one glycosylated peptide reacting with concanavalin A was identified by dot-blotting. Its amino acid sequence allowed the location of this peptide within a highly conserved region in proximity to the N-terminus of the alpha subunits of the 11S globulins from other seeds. The unique presence of a serine residue in a sequence N-X-S of lupin 11S globulin, compared with all other 11S proteins, allows it to be the only protein of this class to bear covalently linked carbohydrate.
在变性条件下，采用离子交换-高效液相色谱法将羽扇豆种子（白羽扇豆，L.）11S贮藏球蛋白（豆球蛋白）主要的44,000 Mrα亚基纯化至同质。用胰蛋白酶消化羧甲基化的亚基，并通过反相高效液相色谱法分离肽片段。通过斑点印迹法仅鉴定出一个与伴刀豆球蛋白A反应的糖基化肽。其氨基酸序列确定了该肽在其他种子11S球蛋白α亚基N端附近高度保守区域内的位置。与所有其他11S蛋白相比，羽扇豆11S球蛋白的N-X-S序列中独特存在丝氨酸残基，使其成为这类蛋白中唯一带有共价连接碳水化合物的蛋白。
