Ertl H, Mengele R, Wenzl S, Engel J, Sumper M
Lehrstuhl Biochemie I, Universität Regensburg, Federal Republic of Germany.
J Cell Biol. 1989 Dec;109(6 Pt 2):3493-501. doi: 10.1083/jcb.109.6.3493.
The extracellular matrix (ECM) of Volvox contains insoluble fibrous layers that surround individual cells at a distance to form contiguous cellular compartments. Using immunological techniques, we identified a sulfated surface glycoprotein (SSG 185) as the monomeric precursor of this substructure within the ECM. The primary structure of the SSG 185 poly-peptide chain has been derived from cDNA and genomic DNA. A central domain of the protein, 80 amino acid residues long, consists almost exclusively of hydroxyproline residues. The chemical structure of the highly sulfated polysaccharide covalently attached to SSG 185 has been determined by permethylation analysis. As revealed by EM, SSG 185 is a rod-shaped molecule with a 21-nm-long polysaccharide strand protruding from its central region. The chemical nature of the cross-links between SSG 185 monomers is discussed.
团藻的细胞外基质（ECM）包含不溶性纤维层，这些纤维层在一定距离围绕单个细胞，形成连续的细胞区室。利用免疫学技术，我们鉴定出一种硫酸化表面糖蛋白（SSG 185）是ECM中这种亚结构的单体前体。SSG 185多肽链的一级结构已从cDNA和基因组DNA推导得出。该蛋白的一个中央结构域长80个氨基酸残基，几乎完全由羟脯氨酸残基组成。通过全甲基化分析确定了与SSG 185共价连接的高度硫酸化多糖的化学结构。如电子显微镜所示，SSG 185是一种杆状分子，有一条21纳米长的多糖链从其中心区域伸出。文中讨论了SSG 185单体之间交联的化学性质。
