Deuel T F, Keim P S, Farmer M, Heinrikson R L
Proc Natl Acad Sci U S A. 1977 Jun;74(6):2256-8. doi: 10.1073/pnas.74.6.2256.
Human platelet factor 4, a protein that binds heparin, has been purified to apparent homogeneity and the complete amino acid sequence of the protein has been determined. The 70-residue polypeptide chain contains no methionine, tryptophan, or phenylalanine, and contains only a single tyrosyl residue. The sequence analysis demonstrates a highly negatively charged amino-terminal region. The carboxyl-terminal region of the polypeptide is unusual in that it contains a repetitive clustering of positively charged and hydrophobic pairs of amino acids; preliminary evidence suggests that this domain may play a role in the binding of heparin.
人血小板因子4是一种能结合肝素的蛋白质，已被纯化至表观均一，其完整的氨基酸序列也已确定。这条由70个残基组成的多肽链不含甲硫氨酸、色氨酸或苯丙氨酸，仅含有一个酪氨酸残基。序列分析表明其氨基末端区域带高度负电荷。该多肽的羧基末端区域不同寻常，因为它含有带正电荷和疏水的氨基酸对的重复簇集；初步证据表明该结构域可能在肝素结合中起作用。
