Krystek S R, Dias J A, Andersen T T
Department of Biochemistry A-10, Albany Medical College, New York 12208.
Biochemistry. 1991 Feb 19;30(7):1858-64. doi: 10.1021/bi00221a019.
Peptides corresponding to the entire sequence of the alpha-subunit of the human glycoprotein hormones were synthesized by using standard solid-phase procedures. Purified peptides were incubated in the presence of alpha- and beta-subunits of bovine lutropin, and subunit recombination was monitored by difference spectroscopy, reverse-phase high-pressure liquid chromatography, and gel filtration chromatography. Although the binding of alpha-peptides to either subunit could not be detected by these techniques, it was possible to demonstrate that some peptides could inhibit the recombination of alpha- and beta-subunits. Specifically, alpha-peptide 33-58 allowed only 0-11% of subunit recombination in 24 h (38-56% after 48 h), while alpha-peptide 51-65 allowed 10-60% of subunits to recombine in 24 h (65-94% in 48 h). Peptides 1-15, 11-27, 22-39, 61-78, and 73-92 of the alpha-subunit could not inhibit subunit recombination at any time or at any concentration tested. The data suggest that at least a portion of the alpha-subunit contact site has been identified, and results are discussed in terms of protein structure assessment tools.
采用标准固相方法合成了与人类糖蛋白激素α亚基全序列相对应的肽段。将纯化后的肽段与牛促黄体激素的α亚基和β亚基一起孵育，通过差示光谱法、反相高压液相色谱法和凝胶过滤色谱法监测亚基重组情况。尽管通过这些技术无法检测到α肽段与任一亚基的结合，但有可能证明某些肽段能够抑制α亚基和β亚基的重组。具体而言，α肽段33 - 58在24小时内仅允许0 - 11%的亚基重组（48小时后为38 - 56%），而α肽段51 - 65在24小时内允许10 - 60%的亚基重组（48小时内为65 - 94%）。α亚基的肽段1 - 15、11 - 27、22 - 39、61 - 78和73 - 92在任何测试时间或浓度下均不能抑制亚基重组。这些数据表明，至少已确定了α亚基接触位点的一部分，并根据蛋白质结构评估工具对结果进行了讨论。
