Chou K C, Zhang C T, Kézdy F J, Poorman R A
Upjohn Laboratories, Kalamazoo, Michigan 49007-4940, USA.
Proteins. 1995 Feb;21(2):118-26. doi: 10.1002/prot.340210205.
The specificity of UDP-GalNAc:polypeptide N-acetylgalactosaminytransferase (GalNAc-transferase) is consistent with the existence of an extended site composed of nine subsites, denoted by P4, P3, P2, P1, P0, P1', P2', P3', P4', where the acceptor at P0 is being either Ser or Thr. To predict whether a peptide will react with the enzyme to form a Ser- or Thr-conjugated glycopeptide, a vector projection method is proposed which uses a training set of amino acid sequences surrounding 90 Ser and 106 Thr O-glycosylation sites extracted from the National Biomedical Research Foundation Protein Database. The model postulates independent interactions of the 9 amino acid moieties with their respective binding sites. The high ratio of correct predictions vs. total predictions for the data in both the training and the testing sets indicates that the method is self-consistent and efficient. It provides a rapid means for predicting O-glycosylation and designing effective inhibitors of GalNAc-transferase.
UDP-N-乙酰半乳糖胺：多肽N-乙酰半乳糖胺基转移酶（GalNAc转移酶）的特异性与一个由九个亚位点组成的扩展位点的存在相一致，这些亚位点分别用P4、P3、P2、P1、P0、P1'、P2'、P3'、P4'表示，其中P0位点的受体为丝氨酸（Ser）或苏氨酸（Thr）。为了预测一个肽是否会与该酶反应形成丝氨酸或苏氨酸缀合的糖肽，提出了一种向量投影方法，该方法使用了从国家生物医学研究基金会蛋白质数据库中提取的90个丝氨酸O-糖基化位点和106个苏氨酸O-糖基化位点周围的氨基酸序列训练集。该模型假定9个氨基酸部分与其各自的结合位点之间存在独立的相互作用。训练集和测试集中数据的正确预测与总预测的高比例表明该方法是自洽且有效的。它为预测O-糖基化和设计有效的GalNAc转移酶抑制剂提供了一种快速方法。
