Role of protozoans on the microbial ectoenzymatic activity during the degradation of macrophytes
Role of protozoans on the microbial ectoenzymatic activity during the degradation of macrophytes
复制标题
大型植物降解过程中原生动物对微生物胞外酶活性的作用
DOI：
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发表时间：
1999
期刊：
影响因子：
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通讯作者：
H. Güde
中科院分区：
文献类型：
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作者：
M. Sala;H. Güde
在大植物马铃薯（Potamogeton pectinatus）浸出的溶解性有机物（DOM）分解过程中，观察到微生物种群和外酶活性的演替。在初始阶段，游离菌群占主导地位。这些细菌产生外酶来水解溶解的碳水化合物（麦芽糖、纤维素糖和淀粉）。当嗜菌原生动物进入样品时，游离细菌几乎消失，然后发现大部分细菌附着，定植在大型植物颗粒上。原生动物种群也呈现出先生长异养纳米鞭毛虫（HNF），再发育较大原生动物纤毛虫和变形虫的演替过程。在第二阶段，检测到纤维素和纤维素等结构多糖的高活性降解。在大型植物的降解过程中，HNF似乎起着重要的作用，因为它们主要以游离细菌为食，而让附着的细菌生长。因此，它们促进了从非结构多糖水解到结构多糖水解的转变。
A succession of microbial populations and ectoenzymatic activities was observed during the decomposition of the dissolved organic matter (DOM) leached from the macrophyte Potamogeton pectinatus. In an initial phase, free bacterial populatlons dominated. These bacteria produced ectoenzyrnes to hydrolyze dissolved carbohydrates (maltose, cellobiose and starch). When bacterivorous Protozoa entered the sample, free bacteria almost disappeared and most of the bacteria were then found attached, colonizing the macrophyte particles. Protozoan populations also showed a succession where heterotrophic nanoflagellates (HNF) grew first and then larger Protozoa, ciliates and amoeba, developed. During this second phase, high activities of degradation of structural polysaccharides such as cellulose and hernicellulose were detected. HNF seemed to play an important role during the degradation of macrophytes because they grazed mainly on free bacteria and left the attached bacteria to grow. Thus, they promoted a shift from the hydrolysis of non-structural to structural polysaccharides.