Nitrate-Driven Trophic Association of Sulfur-Cycling Microorganisms in Tsunami-Deposited Marine Sediment Revealed by High-Sensitivity <sup>13</sup>C-Bicarbonate Probing
Nitrate-Driven Trophic Association of Sulfur-Cycling Microorganisms in Tsunami-Deposited Marine Sediment Revealed by High-Sensitivity <sup>13</sup>C-Bicarbonate Probing
复制标题
高灵敏度<sup>13</sup>C-碳酸氢盐探测揭示了海啸沉积的海洋沉积物中硝酸盐驱动的硫循环微生物的营养关联
DOI：
10.1021/acs.est.0c08191
复制
发表时间：
2021
影响因子：
11.4
通讯作者：
Hori Tomoyuki
中科院分区：
文献类型：
--
作者：
Aoyagi Tomo;Katayama Yoko;Aizawa Hidenobu;Takasaki Mitsuru;Hori Tomoyuki
尽管在海啸沉积的海洋沉积物中，硝酸盐改良剂使依赖于硝化作用的化能无机营养型硫氧化剂增殖，但它们在海洋地球化学碳转移中的生态生理作用尚未得到解决。我们采用时间分辨的高灵敏度13 C-碳酸氢根探针的rRNA揭示的碳固定和硝酸盐修正的沉积物微生物的营养关系。硝酸盐还原和硫氧化沿着同时发生，在培养的前4天，13 CO2和溶解的碳酸氢盐浓度显著降低，在此期间，硫单胞菌属HDS 01和硫代碱螺菌属（Thioalkalispirasp.）HDS 22的亲戚，和硫酸盐还原异养生物，即，脱硫菌属和Desulfofustis glycoicus的近缘种，活性碳13 C.这表明硫氧化剂和硫酸盐还原剂通过直接碳转移相互紧密结合。亲属的fermentalThalassomonassediminis和水解Pararheinheimeraaquatica，除了各种硫循环微生物，显着同化13 C在第14天。虽然没有检测到13 C的掺入，互养型挥发性脂肪酸氧化剂和氢营养型产甲烷菌显着表达其16 S rRNA分子在第21天，表明这些最终的分解者在后者营养有限的条件下的代谢活化。结果表明，硝酸盐驱动的硫循环微生物的营养协会和随后的微生物活化和多样化，触发海洋生态系统功能的恢复。
Although denitrification-dependent chemolithotrophic sulfur oxidizers proliferated in tsunami-deposited marine sediment with nitrate amendment, their ecophysiological roles in biogeochemical carbon transfer are not addressed. We employed time-resolved high-sensitivity13C-bicarbonate probing of rRNA to unveil the carbon fixation and resulting trophic relationship of the nitrate-amended sediment microorganisms. Nitrate reduction and sulfur oxidation co-occurred along with significant decreases in the13CO2and dissolved bicarbonate concentrations for the first 4 days of the incubation, during which the denitrification-dependent sulfur-oxidizing chemolithotrophs, i.e., theSulfurimonassp. HDS01 andThioalkalispirasp. HDS22 relatives, and the sulfate-reducing heterotrophs, i.e., theDesulfobulbusspp. andDesulfofustis glycolicusrelatives, actively incorporated13C. These indicated that the sulfur oxidizers and sulfate reducers were tightly associated with each other through the direct carbon transfer. Relatives of the fermentativeThalassomonas sediminisand the hydrolyticPararheinheimera aquatica, in addition to various sulfur-cycling microorganisms, significantly assimilated13C at day 14. Although the incorporation of13C was not detected, a syntrophic volatile-fatty-acid oxidizer and hydrogenotrophic methanogens significantly expressed their 16S rRNA molecules at day 21, indicating the metabolic activation of these final decomposers under the latter nutrient-limited conditions. The results demonstrated the nitrate-driven trophic association of sulfur-cycling microorganisms and the subsequent microbial activation and diversification, triggering the restoration of the marine ecosystem function.