Biofouling Co
431
Part B | 15.1
15. Biofouling Control by Quorum Quenching
Vipin C. Kalia, Prasun Kumar, Shunmughiah K. T. Pandian, Prince Sharma
Bacteria above a threshold cell density regulate
the expression of a specific group of their genes in
response to small signal molecules called autoinducers. This twitter communication phenomenon
is called quorum sensing (QS). Among the various genetic expressions mediated by QS, biofilm
formation and expression of virulence factors are
the most prominent. These phenotypes are a major cause of concern for health departments and
a wide range of industries dealing especially with
drinking water, waste water reclamation, and
desalination. This phenomenon leads to heavy
economic losses. Efforts to disrupt biofilms have
met with little success. In fact, bacteria within
the biofilms are 1000 times more resistant to
antibiotics than their planktonic counterparts.
Biosensors or reporter strains have been developed to screen QS inhibitors. A potential approach
to inhibit the process of biofouling is to interfere
with bacterial QS signals. QS inhibiting enzymes
and molecules have been isolated from a wide
range of organisms such as bacteria, fungi, algae,
and marine organisms. Efforts to disrupt biofilm
15.1 Overview ............................................. 431
15.2 Bacterial Biosensors............................. 432
15.3 Quorum Quenching (QQ) ....................... 432
15.3.1 Enzymes ................................... 432
15.3.2 Quorum Sensing Inhibitors (QSIs) 433
15.3.3 Designing Antifouling Agents...... 435
15.3.4 Fouling – Release Coatings......... 436
15.4 Applications ........................................ 436
15.4.1 Clinical Settings ......................... 436
15.4.2 The Pulp and Paper Industry ...... 437
15.4.3 Deterrents/Biocides ................... 437
15.4.4 Antifoulants.............................. 437
15.4.5 Engineered Bacteriophages ........ 438
References................................................... 438
formation have been carried out through designing
antifouling agents that primarily reduce surface
adhesion of the organisms. These include fouling release coatings such as nanocomposites. In
contrast to removing biofilms, there are certain
areas where it is desirable to regenerate biofilm
for a fresh round of biotransformation.
15.1 Overview
Biofouling (BF) in aquacultures, water treatment, the
pulp and paper industry, and marine systems is a major cause of concern for water purification industries,
fisheries, merchant and defense naval departments, and
manmade structures (monuments/paintings). Worldwide it is a problem of high practical and economic
relevance. Micro and macrofoulers can cause severe
industrial problems by increasing drag (leading to increased fuel consumption), promoting metal corrosion,
and reducing heat transfer efficacy of heat exchangers.
A major problem encountered during the production of
drinking water, waste water reclamation, and desalination is the biofilm formation on membrane filters.
Efforts to control this through the use of antifouling
(AF) coating (incorporating biocides such as tributyrin)
have imposed environmental burdens, especially since
their usage has been banned [15.1–4].
The most evident form of BF is the formation of
biofilms, which invariably harbor more than one type
of microorganism. Bacterial biofilms play both negative and positive roles. During processing for drinking
water, biofilms cause fouling of filtration membranes
but act positively as biocatalysts in biologically active
filters, riverbank filtration, and membrane biofilm reactors. In the wastewater treatment biofilms also act as
biocatalysts in fixed film activated sludge, moving bed
biofilm reactors, tertiary filters, and granular sludge,
but cause BF of membrane bioreactors. The underlying
phenomenon of the occurrence of bacterial communities in this specific niche depends largely on their ability
431
Part B | 15.1
15. Biofouling Control by Quorum Quenching
Vipin C. Kalia, Prasun Kumar, Shunmughiah K. T. Pandian, Prince Sharma
Bacteria above a threshold cell density regulate
the expression of a specific group of their genes in
response to small signal molecules called autoinducers. This twitter communication phenomenon
is called quorum sensing (QS). Among the various genetic expressions mediated by QS, biofilm
formation and expression of virulence factors are
the most prominent. These phenotypes are a major cause of concern for health departments and
a wide range of industries dealing especially with
drinking water, waste water reclamation, and
desalination. This phenomenon leads to heavy
economic losses. Efforts to disrupt biofilms have
met with little success. In fact, bacteria within
the biofilms are 1000 times more resistant to
antibiotics than their planktonic counterparts.
Biosensors or reporter strains have been developed to screen QS inhibitors. A potential approach
to inhibit the process of biofouling is to interfere
with bacterial QS signals. QS inhibiting enzymes
and molecules have been isolated from a wide
range of organisms such as bacteria, fungi, algae,
and marine organisms. Efforts to disrupt biofilm
15.1 Overview ............................................. 431
15.2 Bacterial Biosensors............................. 432
15.3 Quorum Quenching (QQ) ....................... 432
15.3.1 Enzymes ................................... 432
15.3.2 Quorum Sensing Inhibitors (QSIs) 433
15.3.3 Designing Antifouling Agents...... 435
15.3.4 Fouling – Release Coatings......... 436
15.4 Applications ........................................ 436
15.4.1 Clinical Settings ......................... 436
15.4.2 The Pulp and Paper Industry ...... 437
15.4.3 Deterrents/Biocides ................... 437
15.4.4 Antifoulants.............................. 437
15.4.5 Engineered Bacteriophages ........ 438
References................................................... 438
formation have been carried out through designing
antifouling agents that primarily reduce surface
adhesion of the organisms. These include fouling release coatings such as nanocomposites. In
contrast to removing biofilms, there are certain
areas where it is desirable to regenerate biofilm
for a fresh round of biotransformation.
15.1 Overview
Biofouling (BF) in aquacultures, water treatment, the
pulp and paper industry, and marine systems is a major cause of concern for water purification industries,
fisheries, merchant and defense naval departments, and
manmade structures (monuments/paintings). Worldwide it is a problem of high practical and economic
relevance. Micro and macrofoulers can cause severe
industrial problems by increasing drag (leading to increased fuel consumption), promoting metal corrosion,
and reducing heat transfer efficacy of heat exchangers.
A major problem encountered during the production of
drinking water, waste water reclamation, and desalination is the biofilm formation on membrane filters.
Efforts to control this through the use of antifouling
(AF) coating (incorporating biocides such as tributyrin)
have imposed environmental burdens, especially since
their usage has been banned [15.1–4].
The most evident form of BF is the formation of
biofilms, which invariably harbor more than one type
of microorganism. Bacterial biofilms play both negative and positive roles. During processing for drinking
water, biofilms cause fouling of filtration membranes
but act positively as biocatalysts in biologically active
filters, riverbank filtration, and membrane biofilm reactors. In the wastewater treatment biofilms also act as
biocatalysts in fixed film activated sludge, moving bed
biofilm reactors, tertiary filters, and granular sludge,
but cause BF of membrane bioreactors. The underlying
phenomenon of the occurrence of bacterial communities in this specific niche depends largely on their ability