A case study on chemical defense based on quorum sensing: antibacterial activity of sponge-associated bacterium Pseudoalteromonas sp NJ6-3-1 induced by quorum sensing mechanisms
A case study on chemical defense based on quorum sensing: antibacterial activity of sponge-associated bacterium Pseudoalteromonas sp NJ6-3-1 induced by quorum sensing mechanisms
复制标题
基于群体感应的化学防御案例研究：海绵相关细菌假交替单胞菌的抗菌活性。
DOI：
10.1007/s13213-010-0129-x
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发表时间：
2011-06-01
影响因子：
3
通讯作者：
Wang, Xiaoru
中科院分区：
文献类型：
--
作者：
Guo, Xiuchun;Zheng, Li;Wang, Xiaoru
A case study to investigate the relationship between antibacterial activity and quorum sensing mechanisms was carried out on a sponge-associated bacterium with remarkable biological activities: Pseudoalteromonas sp. NJ6-3-1. The dependence of active substance production on cell density was studied under various growth conditions. Bacteria NJ6-3-1 was found to start producing antibacterial compounds only when cell density reached the threshold value of OD630 = 0.4. To simulate the competitive real marine environment, NJ6-3-1 at low cell density (OD630 value below the required threshold value) was co-cultured with the terrestrial bacterium Staphylococcus aureus. Antibacterial activity assays indicated the existence of some signal molecules in the metabolites of S. aureus that could induce NJ6-3-1 to produce antibacterial substances even at low cell density. Three diketopiperazines (DKPs) as metabolites and potential autoinducers of NJ6-3-1 were synthesized and co-cultured with low density NJ6-3-1. The antibacterial activity assay showed that one of these DKPs—cyclo-(l-Phe-l-Val)—was the autoinducer and could indeed induce NJ6-3-1 to produce antibacterial substances under low cell density. Our results thus provide preliminary support to the hypothesis that the antibacterial activity of NJ6-3-1 is controlled by the quorum sensing system in both an intra-species and an inter-species manner.
