Sandhu Noreen, Duus Karen, Jørgensen Charlotte S, Hansen Paul R, Bruun Susanne W, Pedersen Lars Ø, Højrup Peter, Houen Gunnar
Department of Autoimmunology, Statens Serum Institut, Artillerivej 5, DK-2300 Copenhagen, Denmark.
Biochim Biophys Acta. 2007 Jun;1774(6):701-13. doi: 10.1016/j.bbapap.2007.03.019. Epub 2007 Apr 6.
Calreticulin is a molecular chaperone with specificity for polypeptides and N-linked monoglucosylated glycans. In order to determine the specificity of polypeptide binding, the interaction of calreticulin with polypeptides was investigated using synthetic peptides of different length and composition. A large set of available synthetic peptides (n=127) was tested for binding to calreticulin and the results analysed by multivariate data analysis. The parameter that correlated best with binding was hydrophobicity while beta-turn potential disfavoured binding. Only hydrophobic peptides longer than 5 amino acids showed binding and a clear correlation with hydrophobicity was demonstrated for oligomers of different hydrophobic amino acids. Insertion of hydrophilic amino acids in a hydrophobic sequence diminished or abolished binding. In conclusion our results show that calreticulin has a peptide-binding specificity for hydrophobic sequences and delineate the fine specificity of calreticulin for hydrophobic amino acid residues.
钙网蛋白是一种对多肽和N - 连接的单葡萄糖基化聚糖具有特异性的分子伴侣。为了确定多肽结合的特异性，使用不同长度和组成的合成肽研究了钙网蛋白与多肽的相互作用。测试了大量可用的合成肽（n = 127）与钙网蛋白的结合，并通过多变量数据分析对结果进行分析。与结合最相关的参数是疏水性，而β - 转角倾向不利于结合。只有长度超过5个氨基酸的疏水肽显示出结合，并且对于不同疏水氨基酸的寡聚体，疏水性与结合之间存在明显的相关性。在疏水序列中插入亲水性氨基酸会减少或消除结合。总之，我们的结果表明钙网蛋白对疏水序列具有肽结合特异性，并描绘了钙网蛋白对疏水氨基酸残基的精细特异性。
