The LuxS/AI-2 Quorum-Sensing System Regulates the Algicidal Activity of Shewanella xiamenensis Lzh-2

Abstract

Cyanobacterial blooming is an increasing environmental issue all over the world. Algicidal bacteria are potential tools for the control of algal blooms. The algicidal activity in many bacteria exhibits quorum-sensing (QS) dynamics and the regulatory mechanism of this activity in these bacteria is unclear. In this study, combining genomic sequencing and genome editing, we have identified that the primary quorum-sensing system in the isolated algicidal strain Shewanella xiamenensis Lzh-2 is the LuxS/AI-2 signaling pathway. Disruption of the QS system through recombination deletion of the LuxS gene led to a loss of algicides production and algicidal activity. Restoration of the LuxS gene in the deletion mutant compensated the QS system and recovered the algicidal activity. Consequently, we proved that Lzh-2 regulates the algicidal activity through LuxS/AI-2 quorum-sensing system.

Recent Advances in the Research on the Anticyanobacterial Effects and Biodegradation Mechanisms of Microcystis aeruginosa with Microorganisms

“…[109] and Hahella sp. [31] can produce prodigiosin to inhibit M. aeruginosa, and the prodigiosin production is regulated by LuxI and LuxR, which are the crucial genes of AHLs [126]. The QS signal molecule (C4-HSL), which belongs to the classic AHL-based LuxIR-type QS system of Gram-negative bacteria, is responsible for the synthetic process of the anticyanobacterial compound (3-methylindole) from Aeromonas sp.…”

“…GLY-2107 [69]. During the anticyanobacterial process, the QS systems of Gram-negative bacteria produce AHLs signaling molecules, which are synthesized by the basic regulatory protein of LuxI [69,88,126].…”

“…generally use AI-2 as the signal molecules in QS systems [125]. The anticyanobacterium S. xiamenensis Lzh-2 exhibits QS behavior, and the LuxS gene is crucial for the AI-2 type QS system; obviously, the anticyanobacterial activity of S. xiamenensis Lzh-2 is regulated through the LuxS/AI-2 QS system by inducing the production of anticyanobacterial compounds 2, 3-indolinedione and cyclo(Gly-Pro) [126]. The AI-2 type QS behavior is present in Bacillus sp.…”

Adding Metal Ions to the Bacillus mojavensis D50 Promotes Biofilm Formation and Improves Ability of Biocontrol

“…The luxS/AI-2 quorum sensing (QS) system is an important factor affecting biofilm formation [18]. Many studies have reported that the gene of luxS influences the formation of biofilms, such as Shewanella xiamenensis [19] and Lactobacillus reuteri [20]. In addition, the QS system can also regulate the probiotic activities of lactic acid bacteria [21].…”