Department of Biochemistry and Molecular Biology-SCB, Parana Federal University, P.O. Box 19046, 81531-990 Curitiba, PR, Brazil.
Phytochemistry. 2010 Aug;71(11-12):1400-9. doi: 10.1016/j.phytochem.2010.04.021. Epub 2010 May 18.
Arabinogalactan-proteins (AGPs), found in the culture medium of suspension cells of Araucaria angustifolia grown in plant growth regulator-free and plant growth regulator-containing BM media, BM0 and BM2, respectively, were evaluated quantitatively and qualitatively. The concentrated extracellular fractions (CEFs), obtained from suspension cell cultures grown for 20 days in BM0 and BM2 media yielded two fractions, CEF-0 and CEF-2, respectively. CEF-0 and CEF-2 was submitted to selective precipitation using the beta-glucosyl Yariv reagent (beta-GlcY) to isolate AGPs for structural characterization; this yielded fractions designated CEF-0YPF and CEF-2YPF, respectively. The monosaccharide composition analysis established that samples were composed of Rha, Ara, Gal and uronic acid in a molar ratio 3:37:55:5 (CEF-0YPF) and 1:37:58:4 (CEF-2YPF), although trace amounts (<0.5 mol%) of Xyl were also found. Methylation analysis of CEF-YPF fractions showed similar results for both CEF-0YPF and CEF-2YPF, with non-reducing terminal units of Araf, Arap, Galp, Rhap and Xylp, as well as 3-O-substituted and 5-O-substituted Araf units and 3-O-substituted, 6-O-substituted and 3,6-di-O-substituted Galp units. The amino acid composition analysis established Ser, Ala, and Hyp as major amino acids in both samples. In conclusion, this investigation has shown that CEF-0YPF and CEF-2YPF contain macromolecules having typical AGP characteristics, including a Hyp/Ala/Ser-rich protein moiety, a (1-->3) and/or (1-->6) linked beta-d-galactopyranosyl main chain substituted by Gal, Ara, Rha and Xyl residues, and binding affinity for beta-GlcY and monoclonal anti-AGP antibodies.
阿拉伯半乳聚糖蛋白（AGPs），存在于在植物生长调节剂无和含植物生长调节剂的 BM 培养基（分别为 BM0 和 BM2）中生长的南洋杉悬浮细胞的培养介质中，分别进行了定量和定性评估。从在 BM0 和 BM2 培养基中生长 20 天的悬浮细胞培养物中获得的浓缩细胞外部分（CEF），分别得到 CEF-0 和 CEF-2 两个部分。使用β-葡萄糖基 Yariv 试剂（β-GlcY）对 CEF-0 和 CEF-2 进行选择性沉淀，以分离用于结构表征的 AGPs；分别得到 CEF-0YPF 和 CEF-2YPF 两个部分。单糖组成分析确定样品由 Rha、Ara、Gal 和糖醛酸组成，摩尔比为 3:37:55:5（CEF-0YPF）和 1:37:58:4（CEF-2YPF），尽管也发现痕量（<0.5 mol%）的 Xyl。CEF-YPF 部分的甲基化分析表明，CEF-0YPF 和 CEF-2YPF 具有相似的结果，非还原端单元有 Araf、Arap、Galp、Rhap 和 Xylp，以及 3-O-取代和 5-O-取代的 Araf 单元和 3-O-取代、6-O-取代和 3,6-二-O-取代的 Galp 单元。氨基酸组成分析表明，Ser、Ala 和 Hyp 是这两种样品中的主要氨基酸。总之，本研究表明，CEF-0YPF 和 CEF-2YPF 含有具有典型 AGP 特征的大分子，包括富含 Hyp/Ala/Ser 的蛋白质部分、由 Gal、Ara、Rha 和 Xyl 残基取代的（1-->3）和/或（1-->6）连接的β-d-半乳糖吡喃基主链，以及与β-GlcY 和单克隆抗 AGP 抗体的结合亲和力。
