Li Yao-Chen, Zhu Jian-Rong
School of Environment, Beijing Normal University, Beijing, 100875, China.
Appl Microbiol Biotechnol. 2014 Sep;98(17):7623-32. doi: 10.1007/s00253-014-5815-3. Epub 2014 May 21.
N-acyl homoserine lactone (AHL)-based quorum sensing (QS) has been recognized to play an important role in the formation of biofilm. However, aerobic granular sludge is considered as a special biofilm, and its biological implication and role of AHL-based QS still remain unclear. This study investigated the role of AHL-based QS in aerobic granulation. Results showed that AHLs were necessary to the typical aerobic granulation, and AHL-associated coordination of bacteria in sludge aggregation was sludge density dependent only when it reached a threshold of 1.010 g/mL; AHL-based QS was activated to regulate aerobic granulation. Furthermore, a quorum quenching method was firstly adopted to investigate the role of AHLs in aerobic granules. Results showed inhibition of AHL by acylase that reduced the AHL content in aerobic granules and further weakened its attachment potential, which proved that AHLs play an important role in the formation of aerobic granules. Additionally, the assay of quorum quenching not only proved that AHL-based QS could regulate EPS production but also provided additional evidence for the role of AHLs in aerobic granulation by regulating EPS content and its component proportion.
基于N-酰基高丝氨酸内酯（AHL）的群体感应（QS）已被认为在生物膜形成中发挥重要作用。然而，好氧颗粒污泥被视为一种特殊的生物膜，基于AHL的QS在其中的生物学意义和作用仍不清楚。本研究调查了基于AHL的QS在好氧颗粒化过程中的作用。结果表明，AHL对典型的好氧颗粒化是必需的，且污泥聚集中细菌与AHL相关的协同作用仅在污泥密度达到1.010 g/mL阈值时才依赖于污泥密度；基于AHL的QS被激活以调节好氧颗粒化。此外，首次采用群体淬灭方法研究AHL在好氧颗粒中的作用。结果表明，酰化酶对AHL的抑制降低了好氧颗粒中的AHL含量，并进一步削弱了其附着潜力，这证明AHL在好氧颗粒形成中起重要作用。此外，群体淬灭分析不仅证明基于AHL的QS可以调节胞外聚合物（EPS）的产生，还通过调节EPS含量及其组成比例为AHL在好氧颗粒化中的作用提供了额外证据。
