Meneghetti Maria Cecília Zorél, Gesteira Ferreira Tarsis, Tashima Alexandre Keiji, Chavante Suely F, Yates Edwin Alexander, Liu Jian, Nader Helena Bonciani, Lima Marcelo A
Disciplina de Biologia Molecular, Departamento de Bioquímica, Escola Paulista de Medicina, UNIFESP, São Paulo, Brazil.
Org Biomol Chem. 2017 Aug 16;15(32):6792-6799. doi: 10.1039/c7ob01533j.
3-O-Sulfotransferase enzyme (sHS) from Litopenaeus vannamei was cloned and its substrate specificity was investigated against a number of GAG structures, including modified heparin polysaccharides and model oligosaccharides. For the heparin polysaccharides, derived from porcine intestinal mucosa heparin, sulfate groups were incorporated into glucosamine residues containing both N-sulfated and N-acetylated substitution within the regions of the predominant repeating disaccharide, either I-A or I-A. However, the resulting polysaccharides did not stabilize antithrombin, which is correlated with anticoagulant activity. It was also shown that the enzyme was able to sulfate disaccharides, I-A and G-A. The results further illustrate that 3-O-sulfation can be induced outside of the classical heparin-binding pentasaccharide sequence, show that 3-O-sulfation of glucosamine is not a sufficient condition for antithrombin stabilization and suggest that the use of this enzyme during HS biosynthesis may not occur as the final enzymatic step.
克隆了凡纳滨对虾的3-O-磺基转移酶（sHS），并研究了其对多种糖胺聚糖结构的底物特异性，这些结构包括修饰的肝素多糖和模型寡糖。对于源自猪肠黏膜肝素的肝素多糖，在主要重复二糖区域（I-A或I-A）内，硫酸基团被引入到同时含有N-硫酸化和N-乙酰化取代的葡糖胺残基中。然而，所得多糖并未使抗凝血酶稳定，这与抗凝活性相关。还表明该酶能够使二糖I-A和G-A硫酸化。结果进一步说明，3-O-硫酸化可在经典肝素结合五糖序列之外诱导产生，表明葡糖胺的3-O-硫酸化不是抗凝血酶稳定化的充分条件，并提示在硫酸乙酰肝素生物合成过程中该酶可能不作为最终酶促步骤发挥作用。
