Studies on the formation of basic ground of tideland ecosystem from the viewpoints of sediment protease activities.

在潮滩沉积物中，微生物分泌胞外酶，支持废物净化和为植物和浮游植物补充营养。在分泌的酶中，蛋白酶已知在沿海生态系统的氮循环中发挥重要作用。对卡莫河口潮滩22个站位的沉积物蛋白酶活性进行了测定。活动的等值线图显示，高活动点位于两个栖息地地区的Uca lactea和马尾藻fulvellum。此外，统计分析表明，蛋白酶活性与潮滩沉积物中的有机碳和氮的浓度相关。实际上，负载的沉积物与血清白蛋白作为蛋白质底物诱导蛋白酶活性显着增强，而不增加ATP生物量。电泳分析清楚地揭示了蛋白质加载诱导的蛋白酶条带的存在。这些结果表明，蛋白质负载刺激某些微生物分泌蛋白酶。

In tideland sediments, microorganisms secrete extracellular enzymes, which support waste purification and nutrient supplementation to plants and phytoplankton. Among the secreted enzymes, proteases are known to play essential roles in nitrogen cycling in coastal ecosystems. In this study, the protease activities of sediments were assayed at 22 sites in the Kamo River Estuary Tideland. The contour map of the activities showed spots of high activity located in two habitat areas for Uca lactea and Sargassum fulvellum. Moreover, statistical analysis indicated that the protease activity was correlated with the concentrations of organic carbon and nitrogen in the tideland sediments. Actually, loading of sediments with serum albumin as a protein substrate induced marked enhancement of protease activities without increasing of ATP biomass. Electrophoretic analysis clearly revealed the presence of protease bands induced by protein loading. These results suggest that protein loading stimulates the secretion of proteases by certain microorganisms.