Podolsky D K
J Biol Chem. 1985 Dec 15;260(29):15510-5.
Purified human colonic mucin contains six distinct components which may be separated by DEAE-cellulose chromatography. Past studies defined the structure of oligosaccharide side chains from the most abundant species III, IV, and V which elute at intermediate salt concentrations. In these studies the structures of oligosaccharide side chains liberated from the remaining early and late eluting species I, II, and VI were determined after isolation by sequential conventional and high performance liquid chromatography through combination of gas chromatography, methylation analysis, and sequential glycosidase digestion. Mucin species I, II, and VI contained a less varied array of discrete oligosaccharide structures than that observed in the major mucin components. Mucin species I and II contained five and 10 structures, respectively, which account for 68 and 71% of total oligosaccharide content in these fractions. The predominant oligosaccharides of mucin species I included three neutral structures: a disaccharide GlcNAc beta (1-3)GalNAc-ol, a trisaccharide Gal beta (1-4)GlcNAc beta (1-3)GalNAc-ol, and a tetrasaccharide GlcNAc beta (1-4)Gal beta (1-4)GlcNAc beta (1-3)GalNAc-ol as well as two acidic components representing the sialylated forms of two of these oligosaccharides. Mucin species II contained these same oligosaccharides as well as four additional acidic structures, notably a disaccharide Neu alpha (2-6)GalNAc-ol and a hexasaccharide Gal beta (1-4)GlcNAc beta (1-3)Gal beta (1-4)GlcNAc beta (1-3) (NeuAc alpha (2-6))-GalNAc-ol, not identified in any other mucin species. The late eluting mucin species VI contained at least five discrete neutral oligosaccharides and six major acidic structures. While the majority of these structures had been previously isolated from the earlier eluting mucin species IV and V, species VI also contained di- and trisialylated oligosaccharides not identified in other mucin species. In conjunction with earlier studies of the major mucin species III, IV, and V, these data define the range of oligosaccharide structures present in human colonic mucin. These studies demonstrate that human colonic mucin possesses species with characteristic and distinguishable combinations of oligosaccharides which reflect variations of common core structures.
纯化的人结肠粘蛋白含有六种不同的成分，可通过二乙氨基乙基纤维素色谱法分离。过去的研究确定了在中等盐浓度下洗脱的最丰富的III、IV和V型寡糖侧链的结构。在这些研究中，通过气相色谱、甲基化分析和顺序糖苷酶消化相结合的常规和高效液相色谱顺序分离后，确定了从其余早期和晚期洗脱的I、II和VI型中释放的寡糖侧链的结构。I、II和VI型粘蛋白所含离散寡糖结构的种类比主要粘蛋白成分中观察到的要少。I型和II型粘蛋白分别含有5种和10种结构，分别占这些组分中总寡糖含量的68%和71%。I型粘蛋白的主要寡糖包括三种中性结构：二糖GlcNAcβ(1-3)GalNAc-ol、三糖Galβ(1-4)GlcNAcβ(1-3)GalNAc-ol和四糖GlcNAcβ(1-4)Galβ(1-4)GlcNAcβ(1-3)GalNAc-ol，以及两种酸性成分，代表其中两种寡糖的唾液酸化形式。II型粘蛋白含有这些相同的寡糖以及另外四种酸性结构，特别是二糖Neuα(2-6)GalNAc-ol和六糖Galβ(1-4)GlcNAcβ(1-3)Galβ(1-4)GlcNAcβ(1-3)(NeuAcα(2-6))-GalNAc-ol，在任何其他粘蛋白种类中均未发现。晚期洗脱的VI型粘蛋白含有至少五种离散的中性寡糖和六种主要的酸性结构。虽然这些结构中的大多数先前已从早期洗脱的IV型和V型粘蛋白中分离出来，但VI型还含有在其他粘蛋白种类中未发现的二唾液酸化和三唾液酸化寡糖。结合对主要粘蛋白III、IV和V型的早期研究，这些数据确定了人结肠粘蛋白中存在的寡糖结构范围。这些研究表明，人结肠粘蛋白具有具有特征性和可区分的寡糖组合的种类，这些组合反映了常见核心结构的变化。
