Nitrogen mobilization from protein-polyphenol complex by ericoid and ectomycorrhizal fungi
Nitrogen mobilization from protein-polyphenol complex by ericoid and ectomycorrhizal fungi
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DOI：
10.1016/s0038-0717(96)00258-1
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发表时间：
1996-12-01
影响因子：
9.7
通讯作者：
Read, DJ
中科院分区：
文献类型：
--
作者：
Bending, GD;Read, DJ
菌根增生的森林和石楠地土壤表层通常含有大量的多酚物质。这些有可能结合有机氮在顽固性复合体，从而影响氮的有效性真菌共生体。研究了森林土壤水提物的蛋白质结合能力。从桦树和松树中提取的蛋白质即使在低浓度下也能与蛋白质结合。采用可溶性多酚单宁酸（TA）和蛋白牛血清白蛋白（BSA）研究了多酚对外生菌根（ECM）、ericoid菌根和分解木材的腐生真菌蛋白质有效性的影响。虽然腐生真菌能够动员沉淀，但18种ECM真菌中只有3种能够这样做。类菌根真菌能够部分清除沉淀。结果表明，类菌根真菌可以获得TA络合蛋白中含有的N，而ECM真菌则不能。菌根真菌胞外蛋白酶在TA的作用下保持活性，而ECM真菌胞外蛋白酶则受到抑制。类菌根真菌和几种ECM真菌对TA- bsa沉淀中的TA具有代谢能力。1997爱思唯尔科学有限公司
The horizons of forest and heathland soils in which mycorrhizal roots proliferate typically contain large quantities of polyphenolic materials. These have the potential to bind organic nitrogen in recalcitrant complexes, thereby influencing availability of N to the fungal symbionts. The protein-binding abilities of aqueous extracts of forest soils were examined. and those derived from birch and pine sites were found to bind protein even when present in low concentrations. The effect of polyphenols upon availability of protein to ectomycorrhizal (ECM), ericoid mycorrhizal and wood-decomposing saprophytic fungi was investigated using the soluble polyphenol tannic acid (TA), and protein bovine serum albumin (BSA). While the saprophytic fungi were able to mobilize the precipitate, only three of 18 ECM fungi tested were able to do so. The ericoid mycorrhizal fungi were capable of partial clearance of the precipitate. It was demonstrated that the ericoid mycorrhizal fungi had access to N contained in protein complexed by TA, while ECM fungi did not. The extracellular proteases of ericoid mycorrhizal fungi remained active in the presence of TA, while those of the ECM fungi were inhibited. The ericoid mycorrhizal fungi and several ECM fungi showed abilities to metabolise TA contained in TA-BSA precipitate. (C) 1997 Elsevier Science Ltd.