357
8-epi- malyngamide C, lyngbyoic acid, and lyngbic acid which inhibit LasR of
Pseudomonas aeruginosa responding to exogenous 3OC12-HSL (Dobretsov et al.
2010; Tang and Zhang 2014). Compounds known as Honaucins A-C, isolated from
Leptolyngbya crossbyana, are found to have dual activity, that is, they act both as
anti- inflammatory as well as anti-quorum sensing compounds. Such compounds
can be of tremendous use to produce multifunctional drugs. Marine cyanobacteria
produces various kinds of AHL-dependent quorum sensing inhibitors, and have
most likely evolved strategy to check the associated microbial communities by
intervening with their cell-to-cell communication thereby disrupting the communication process (Koh et al. 2013). Some of the other marine microorganisms have
also been found to produce quorum quenching compounds. Halobacillus salinus, a
Gram-positive bacterium, produces a couple of compounds including N-(2Phenylethyl)-isobutyramide and 3-methyl-N-(2-Phenylethyl)-butyramide which
have the capability of inhibiting violacein biosynthesis of Chromobacterium violaceum CV026 in the presence of exogenous AHLs (Teasdale et al. 2009; Tang and
Zhang 2014). Both Gram-positive Bacillus cereus and Gram-negative Marinobacter
sp. SK-3 produce diketopiperazines (DKPs) which inhibit AHL dependent Quorum
Sensing (Teasdale et al. 2009; Abed et al. 2013; Tang and Zhang 2014). Piericidin
isolated from marine actinobacteria inhibits violacein biosynthesis in
Chromobacterium violaceum CV026 (Ooka et al. 2013; Duncan et al. 2014; Tang
and Zhang 2014). The protective features of halogenated furanones in brine shrimp,
rotifers, and rainbow trout against pathogenic Vibrio species has been well reported
by various researchers (Rasch et al. Rasch et al. 2004; Defoirdt et al. 2006; Tinh
et al. 2007; Tang and Zhang 2014). These marine-derived furanones have also been
found to be effective against lung infections caused by Pseudomonas aeruginosa in
mice (Wu et al. 2004; Tang and Zhang 2014). Some furanones have also been found
to be toxic to rainbow trout, rotifers, and human fibroblasts (Rasch et al. 2004; Tinh
et al. 2007; Tang and Zhang 2014). So, the need of the hour is to produce less toxic
and more effective furanone derivatives commercially that may promote their therapeutic value.
14.4.1.3 Quorum Quenching in Marine Environment – a Resource
to Be Explored
As we all realize that marine environment is one of the exceedingly assorted ecosystem, microorganisms with abilities of producing QS inhibitors remain to be discovered. Scientists have proposed that quorum quenching is liable to be more common in
marine bacteria because a high ratio of quorum quenching bacteria has been reported
(Romero et al. 2012; Tang and Zhang 2014); in addition to this a high incidence of
quorum quenching genes has been discovered in marine metagenomes (Romero et al.
2011; Tang and Zhang 2014; Hentzer and Givskov 2003). Therefore, majority of quorum quenching bacteria may still be undiscovered and the occurrence of quorum
quenching enzymes in marine microbes is also expected to be on the higher side.
Thus, an intensified attempt is needed in the invention of new natural quorum quenching compounds from marine microorganisms as it may prove to be a boon in the field
of developing quorum quenching compounds from natural environments.
14 Quorum Quenching Compounds from Natural Sources
8-epi- malyngamide C, lyngbyoic acid, and lyngbic acid which inhibit LasR of
Pseudomonas aeruginosa responding to exogenous 3OC12-HSL (Dobretsov et al.
2010; Tang and Zhang 2014). Compounds known as Honaucins A-C, isolated from
Leptolyngbya crossbyana, are found to have dual activity, that is, they act both as
anti- inflammatory as well as anti-quorum sensing compounds. Such compounds
can be of tremendous use to produce multifunctional drugs. Marine cyanobacteria
produces various kinds of AHL-dependent quorum sensing inhibitors, and have
most likely evolved strategy to check the associated microbial communities by
intervening with their cell-to-cell communication thereby disrupting the communication process (Koh et al. 2013). Some of the other marine microorganisms have
also been found to produce quorum quenching compounds. Halobacillus salinus, a
Gram-positive bacterium, produces a couple of compounds including N-(2Phenylethyl)-isobutyramide and 3-methyl-N-(2-Phenylethyl)-butyramide which
have the capability of inhibiting violacein biosynthesis of Chromobacterium violaceum CV026 in the presence of exogenous AHLs (Teasdale et al. 2009; Tang and
Zhang 2014). Both Gram-positive Bacillus cereus and Gram-negative Marinobacter
sp. SK-3 produce diketopiperazines (DKPs) which inhibit AHL dependent Quorum
Sensing (Teasdale et al. 2009; Abed et al. 2013; Tang and Zhang 2014). Piericidin
isolated from marine actinobacteria inhibits violacein biosynthesis in
Chromobacterium violaceum CV026 (Ooka et al. 2013; Duncan et al. 2014; Tang
and Zhang 2014). The protective features of halogenated furanones in brine shrimp,
rotifers, and rainbow trout against pathogenic Vibrio species has been well reported
by various researchers (Rasch et al. Rasch et al. 2004; Defoirdt et al. 2006; Tinh
et al. 2007; Tang and Zhang 2014). These marine-derived furanones have also been
found to be effective against lung infections caused by Pseudomonas aeruginosa in
mice (Wu et al. 2004; Tang and Zhang 2014). Some furanones have also been found
to be toxic to rainbow trout, rotifers, and human fibroblasts (Rasch et al. 2004; Tinh
et al. 2007; Tang and Zhang 2014). So, the need of the hour is to produce less toxic
and more effective furanone derivatives commercially that may promote their therapeutic value.
14.4.1.3 Quorum Quenching in Marine Environment – a Resource
to Be Explored
As we all realize that marine environment is one of the exceedingly assorted ecosystem, microorganisms with abilities of producing QS inhibitors remain to be discovered. Scientists have proposed that quorum quenching is liable to be more common in
marine bacteria because a high ratio of quorum quenching bacteria has been reported
(Romero et al. 2012; Tang and Zhang 2014); in addition to this a high incidence of
quorum quenching genes has been discovered in marine metagenomes (Romero et al.
2011; Tang and Zhang 2014; Hentzer and Givskov 2003). Therefore, majority of quorum quenching bacteria may still be undiscovered and the occurrence of quorum
quenching enzymes in marine microbes is also expected to be on the higher side.
Thus, an intensified attempt is needed in the invention of new natural quorum quenching compounds from marine microorganisms as it may prove to be a boon in the field
of developing quorum quenching compounds from natural environments.
14 Quorum Quenching Compounds from Natural Sources