State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China.
University of Chinese Academy of Sciences, Beijing, China.
Nat Commun. 2024 Nov 22;15(1):10148. doi: 10.1038/s41467-024-54616-0.
Aluminium (Al)-tolerant beneficial bacteria confer resistance to Al toxicity to crops in widely distributed acidic soils. However, the mechanism by which microbial consortia maintain Al tolerance under acid and Al toxicity stress remains unknown. Here, we demonstrate that a soil bacterial consortium composed of Rhodococcus erythropolis and Pseudomonas aeruginosa exhibit greater Al tolerance than either bacterium alone. P. aeruginosa releases the quorum sensing molecule 2-heptyl-1H-quinolin-4-one (HHQ), which is efficiently degraded by R. erythropolis. This degradation reduces population density limitations and further enhances the metabolic activity of P. aeruginosa under Al stress. Moreover, R. erythropolis converts HHQ into tryptophan, promoting the synthesis of peptidoglycan, a key component for cell wall stability, thereby improving the Al tolerance of R. erythropolis. This study reveals a metabolic cross-feeding mechanism that maintains microbial Al tolerance, offering insights for designing synthetic microbial consortia to sustain food security and sustainable agriculture in acidic soil regions.
耐铝有益细菌赋予作物在广泛分布的酸性土壤中对铝毒性的抗性。然而，微生物群落在酸和铝毒性胁迫下维持耐铝性的机制尚不清楚。在这里，我们证明了由红球菌和铜绿假单胞菌组成的土壤细菌群落比单独的任何一种细菌都具有更高的耐铝性。铜绿假单胞菌释放群体感应分子 2-庚基-1H-喹啉-4-酮（HHQ），该分子被红球菌有效地降解。这种降解减少了种群密度限制，并进一步增强了铜绿假单胞菌在铝胁迫下的代谢活性。此外，红球菌将 HHQ 转化为色氨酸，促进肽聚糖的合成，肽聚糖是细胞壁稳定性的关键组成部分，从而提高了红球菌的耐铝性。本研究揭示了一种维持微生物耐铝性的代谢交叉喂养机制，为设计合成微生物群落以维持酸性土壤地区的粮食安全和可持续农业提供了新的思路。
