Allotype-related sequence variation of the heavy chain of rabbit immunoglobulin G.
Allotype-related sequence variation of the heavy chain of rabbit immunoglobulin G.
复制标题
兔免疫球蛋白 G 重链的同种异型相关序列变异。
DOI：
10.1042/bj1070753
复制
发表时间：
1968
期刊：
影响因子：
--
通讯作者：
ANm R. R. PORTERt
中科院分区：
文献类型：
--
作者：
By J. W. Prahl;ANm R. R. PORTERt
兔免疫球蛋白G重链存在三种主要的异型模式Aa1-Aa3。从免疫球蛋白IgG纯合子中分离的重链氨基酸组成的比较显示，相对于Aa1和Aa2等位型，Aa3等位型每条链上存在额外的蛋氨酸残基。附加蛋氨酸残基的位置由溴化氰裂解和γ链的胰酶切确定；它与链的fd - fc间区域相吻合。从每个异体中分离并鉴定了相应的31个氨基酸残基的色氨酸肽，结果表明Aa3异体中存在蛋氨酸对苏氨酸的替代，但仅在约70-80%的分子中存在。该色氨酸未见其他异型变异。在n端溴化氰裂解肽中也检测到与异体相关的组成变化。
The heavy chain of rabbit immunoglobulin G exists in three major allotypic patterns, Aa1-Aa3. A comparison of the amino acid compositions of the heavy chains isolated from immunoglobulin IgG homozygous for each allotypic determinant revealed the presence of an additional methionine residue per chain in the Aa3 allotype relative to the Aa1 and Aa2 allotypes. The position of the additional methionine residue was determined by cyanogen bromide cleavage and by tryptic digestion of the gamma-chains; it coincided with the inter-Fd-Fc area of the chain. Isolation and characterization of the corresponding tryptic peptides of 31 amino acid residues from each of the allotypes showed the presence of a methionine-for-threonine replacement in the Aa3 allotype, but only in about 70-80% of the molecules. No other allotypic variations were seen in this tryptic peptide. Allotypically related variations in composition were also detected in the N-terminal cyanogen bromide-cleavage peptide.