Soil oxidoreductase zymography: Visualizing spatial distributions of peroxidase and phenol oxidase activities at the root-soil interface
Soil oxidoreductase zymography: Visualizing spatial distributions of peroxidase and phenol oxidase activities at the root-soil interface
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DOI：
10.1016/j.soilbio.2022.108610
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发表时间：
2022-02
影响因子：
9.7
通讯作者：
Sajedeh Khosrozadeh;A. Guber;A. Kravchenko;Negar Ghaderi;E. Blagodatskaya
中科院分区：
文献类型：
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作者：
Sajedeh Khosrozadeh;A. Guber;A. Kravchenko;Negar Ghaderi;E. Blagodatskaya
有机物质在根际——土壤中最活跃的微生物栖息地——的分解涉及氧化还原酶和水解酶的阵列。利用酶谱技术已经探索了土壤中各种水解活性的空间分布。然而，氧化活性在根际的分布仍有待研究。因此，我们扩展了一种时间推移酶谱技术，使用amplex Red®试剂，可视化和量化玉米根际酚氧化酶和过氧化物酶活性的分布。生长在单生土和非根际土壤中。总氧化活性在根表面最高，在种子根（直径小于0.1 mm）和侧根（直径小于0.5 mm）处分别降至1.26和0.73 mm的背景土壤水平。侧根周围的根际范围比种子根周围的根半径宽59%。活性最高可达30 nmol cm - 2min - 1，以过氧化物酶为主，与根密切相关。结果证实了该方法在研究土壤氧化活性时空分布中的实用性。然而，田间氧化还原酶的实际活性将受到波动的环境条件的强烈控制，如土壤通气性和活性氧的梯度，这在缺氧土壤中尤其需要考虑。
Decomposition of organic material in the rhizosphere – the most dynamic microbial habitat in soil – involves arrays of oxidoreductase and hydrolytic enzymes. Spatial distributions of various hydrolytic activities in soil have already been explored by zymographic techniques. However, the distribution of oxidative activity in the rhizosphere remains to be studied. Thus, we extended a Time-Lapse Zymography technique, usingAmplex Red®reagent, to visualize and quantify distributions of phenol oxidase and peroxidase activities in the rhizosphere ofZeamaysL. growing in a Haplic Phaeozem and the non-rhizospheric soil. The gross oxidative activity was greatest at the root surfaces, and fell to background soil levels 1.26 and 0.73 mm from seminal (>1 mm diameter) and lateral (<0.5 mm diameter) roots, respectively. The rhizosphere extent relative to the root radius was 59% broader around lateral than around seminal roots. The greatest activities, up to 30 nmol cm−2min−1, were peroxidase-dominated and closely associated with roots. The results confirm the utility of the approach for studying spatio-temporal distributions of oxidative activities in soil. However, actual activity of oxidoreductases in the field will be strongly controlled by fluctuating environmental conditions such as soil aeration and the gradient of reactive oxygen species, which need to be considered especially in anoxic soils.