洋底深部裂褶菌在不同环境条件的生长行为

Growth behaviors of deep subseafloor Schizophyllum commune in response to various environmental conditions

摘要:

[目的] 了解洋底深部真菌适应原位环境的生长特征。[方法] 在模拟洋底原位环境因子（压力除外）的培养条件（温度，pH，盐度，Fe²⁺，木质素和NH₄⁺）下，比较了4株分离自洋底约2 km深处含煤沉积物的裂褶菌和2株分离自海洋及陆地生境的裂褶菌的生长速率。[结果] 在本实验所设置的温度（20，30，40，45℃）、氧气（有氧和无氧）、pH（6，8，10）、盐度（淡水，原位水，人工海水）、Fe²⁺（0.27，8.93，89.28μmol/L）、木质素（1，5，10 g/L）和NH₄⁺（0.5，1.0，5.0 g/L）条件下，洋底菌株均比陆地菌株（CFCC7252）和海洋菌株（MCCC 3A00233）生长快，但不同洋底菌株之间也存在生长差异，菌株6R-2-F01和24R-3-F01在厌氧条件下的生长速率显著高于其在有氧条件下的生长速率。[结论] 洋底真菌（如裂褶菌）可能拥有独特的生物学特性，以帮助其适应洋底极端环境，相关研究值得进一步探讨。

Abstract:

[Objective] To understand the growth characteristics of deep subseafloor fungi adapted to the in-situ environment. [Methods] The growth rates of four strains of Schizophyllum commune isolated from coal-bearing sediments about 2 km below the seafloor and two strains isolated from marine and terrestrial habitats were studied by comparative culture under different environmental factors, mimicking the in-situ conditions (except for pressure) such as temperature, pH, salinity, Fe²⁺, lignin, and NH₄⁺. [Results] All the strains of subseafloor fungus grew significantly better than terrestrial (CFCC7252) and marine (MCCC 3A00233) isolated strains under the given culture conditions, including temperature (20, 30, 40, 45 ℃), oxygen (aerobic and anaerobic), pH (6, 8, 10), salinity (freshwater, in-situ water, artificial seawater), Fe²⁺ (0.27, 8.93, 89.28 μmol/L), lignin (1, 5, 10 g/L), and NH₄⁺ (0.5, 1.0, 5.0 g/L). However, there were also differences among different strains in the sedimentary environment below seafloor. The growth rate of strains 6R-2-F01 and 24R-3-F01 under anaerobic conditions was significantly higher than that of aerobic conditions. [Conclusion] Fungi from the subseafloor, such as S. commune, may have distinct biological traits that help them adapt to the extreme marine subsurface environments.