The larvae of Japanese rhinoceros beetle, Trypoxylus dichotomus, feed on dead plant material in forest soils that are derived from fallen leaves broken down by basidiomycete fungi. Our previous work provided an understanding of the degradation of polysaccharides in dead plant material by T. dichotomus larvae and reported the complexity of the physicochemical and biochemical environment of the larval gut. Here, we examined ten divisions of the digestive tract of T. dichotomus larvae for physicochemical and biochemical conditions to elucidate site‐specifically functional properties along the tract. The distribution of potassium ions, pH, and acetic acid differed markedly along the length of the digestive tract with the potassium ion concentration profile closely reflecting that of pH along the length of the digestive tract. Distinct physicochemical environments were maintained in the digestive tract along with site‐specific polysaccharide degradation. Based on these findings, we suggest that there are metabolic relationships between the activities of the enzymes involved in polysaccharide degradation, the presence of intermediate metabolites and location along the digestive tract. Furthermore, we revealed that the anterior region of the gut plays an important role in the degradation of polysaccharides in the digestive tract of T. dichotomus larvae.

中文翻译：

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日本犀牛甲虫幼虫消化道生化特性的特定位点特征，Trypoxylus dichotomus（鞘翅目：金龟子科）

日本犀牛甲虫 (Trypoxylus dichotomus) 的幼虫以森林土壤中的死植物材料为食，这些植物材料来自担子菌真菌分解的落叶。我们之前的工作提供了对 T. dichotomus 幼虫对死亡植物材料中多糖的降解的理解，并报告了幼虫肠道物理化学和生化环境的复杂性。在这里，我们检查了 T. dichotomus 幼虫消化道的 10 个部分的理化和生化条件，以阐明沿消化道的位点特异性功能特性。钾离子、pH 值和乙酸的分布沿消化道长度显着不同，钾离子浓度分布密切反映沿消化道长度的 pH 值分布。随着位点特异性多糖降解，消化道中保持着独特的物理化学环境。基于这些发现，我们认为参与多糖降解的酶的活性、中间代谢物的存在和沿消化道的位置之间存在代谢关系。此外，我们发现肠道前部区域在 T. dichotomus 幼虫消化道中的多糖降解中起着重要作用。中间代谢物的存在和沿消化道的位置。此外，我们发现肠道前部区域在 T. dichotomus 幼虫消化道中的多糖降解中起着重要作用。中间代谢物的存在和沿消化道的位置。此外，我们发现肠道前部区域在 T. dichotomus 幼虫消化道中的多糖降解中起着重要作用。