Novel peptide-saccharide conjugates for prevention of intestinal infection

研究了糖巨肽（GMP）和卵粘蛋白糖肽（OGP）对肠道感染的预防作用，并通过Maillard反应制备了GMP与低聚木糖（XOS）和羧甲基葡聚糖（CMD）的偶联物，以增强GMP的预防作用。用生物素标记的细菌通过ELISA评价GMP与肠道致病菌的结合能力。GMP对沙门氏菌和肠出血性大肠杆菌O 157：H7具有结合能力。OGP与EHEC O 157有结合能力。这些结合能力显着降低唾液酸化酶处理，并完全消除penodate氧化。这些结果表明GMP和OGP中的碳水化合物部分如唾液酸参与与这些细菌的结合。同时观察GMP对病原菌粘附和侵袭Caco-2细胞的影响。GMP对沙门氏菌的粘附和侵袭无明显抑制作用。然而，GMP-XOS和GMP-CMD显著抑制作为感染指标的IL-8的产生。我们的研究结果表明，GMP和OGP作为预防肠道感染的药物是有希望的。

Preventive effects of glycomacropeptide (GMP) and ovomucin glycopeptide (OGP) against intestinal infection were investigated and the conjugates of GMP with xylooligosaccharide (XOS) and carboxymethyldextran (CMD) were prepared by the Maillard reaction to enhance the effect of GMP. Binding ability of GMP to intestinal pathogenic bacteria was evaluated by ELISA with biotinylated bacteria. GMP showed binding ability to Salmonella enteritidis (S.enteritidis) and enterohaemorrhic Escherichia coli O157:H7 (EHEC O157). OGP showed binding ability to EHEC O157. These binding abilities markedly decreased by sialydase treatment and were completely eliminated by penodate oxidation. These results indicated that carbohydrate moieties such as sialic acid in GMP and OGP are involved in binding to these bacteria. The effect of GMP on the adhesion and invasion of pathogenic bacteria to Caco-2 cells was also investigated. GMP was not potent inhibitor to adhesion and invasion of Salmonella infection. However, GMP-XOS and GMP-CMD significantly suppressed IL-8 production which was the index of infection. Our results indicate that GMP and OGP are promising as the agent to prevent intestinal infection.