Part B | 15
438 Part B Tools and Methods in Marine Biotechnology
15.4.5 Engineered Bacteriophages
Phages that kill bacteria in a species-specific manner are
engineered to express the most effective EPS-degrading
enzymes specific to the target biofilm. This strategy
permits the development of a diverse library of biofilmdispersing phages rather than necessitating attempts
to isolate such phages from the environment. These
recombinant phages not only lyse the bacterial cells
rapidly but express and produce the biofilm-degrading
enzymes as well. This autocatalytic mechanism leads
to efficient removal of bacterial biofilms in a wide
range of scenarios, such as industrial, environmental,
and clinical settings [15.42]. This strategy also eliminates the need to produce, purify, and deliver large
doses of enzymes to target sites of infection that are otherwise difficult to access and would lead to improved
and efficient phage therapy for removal of biofilms. For
example, the engineered T7 phage expresses the K1-5
endosialidase enzyme, which allows it to replicate in the
K1 polysaccharide capsule –producing E. coli [15.42].
DspB hydrolyzes adhesions which are important in
the biofilm formation by several bacterial species, including clinical strains. Therefore, recombinant phages
producing DspB can be applied to a large number
of bacterial infections [15.42]. Also, several different
biofilm-forming bacterial species, including E. coli,
produce a group of biofilm promoting factors, required
to produce a mature biofilm. These factors are shared
among different strains and are, therefore, potential targets for an enzymatically engineered phage [15.42].
In contrast to most works which target only the
removal of biofilms and its associated bacteria, a recent approach was aimed at reusing the platform for
a fresh round of biofilms in biorefineries. Here, the
intention was to reuse the platform for chemical transformations. In the initial step, proteins, global regulator
(Hha) and cyclic diguanylate-binding (BdcA), were
engineered to disperse biofilms. The dispersal cells
were then removed through a chemical switch, isopropyl-ˇ-D-thiogalactopyranoside. This technique can
be applied to develop biosensors, biocorrosion, BF, and
bioremediation [15.43].
Recently, QQ has been applied as a practical solution to control BF of membrane bioreactors (MBR)
in water treatment systems. Cells of Rhodococcus
sp. BH4, a QQ bacterium, were entrapped in alginate beads (cell entrapping beads, CEB), and designed
with a porous surface microstructure. When these CEBs
were used in MBRs, a transmembrane pressure of
70 kPa was reached in a time period that was ten
times longer than MBRs without CEBs. The role of
CEBs was dual in controlling the biofilm formation:
biological, as quorum quenchers of AHLs produced
by BF bacteria, thus inhibiting the synthesis of extracellular polymeric substances involved in biofilm
formation, and physical as the source of friction between CEBs colliding with biofilm on the membrane
surface. Sloughing off of biofilm was more pronounced
with the QQ effect than friction. QQ is thus seen as
an efficient and economical alternative to control BF of
MBRs [15.44].
We should take inspiration from natural sources,
especially skins of marine animals and microbes associated with them to develop the most sustainable marine
technologies to control BF [15.9, 10].
References
15.1
D. Paul, Y.S. Kim, K. Ponnusamy, J.H. Kweon: Application of quorum quenching to inhibit biofilm
fermentation, Environ. Eng. Sci. 26(8), 1319–1324
(2009)
15.2
K.-M. Yeon, W.-S. Cheong, H.-S. Oh, W.-N. Lee, B.K. Hwang, C.-H. Lee, H. Beyenal, Z. Lewandowski:
Quorum sensing: A new biofouling control
paradigm in a membrane bioreactor for advanced
waste water treatment, Environ. Sci. Technol.
43(2), 380–385 (2009)
15.3
S. Dobretsov, M. Teplitski, M. Bayer, S. Gunasekra,
P. Proksch, V.J. Paul: Inhibition of marine biofouling by bacterial quorum sensing inhibitors,
Biofouling 27(8), 893–905 (2011)
15.4
M.P. Schultz, J.A. Bendick, E.R. Holm, W.M. Hertel: Economic impact of biofouling on a
naval surface ship, Biofouling 27(1), 87–98
(2011)
15.5
V.C. Kalia: Quorum sensing inhibitors: An overview,
Biotechnol. Adv. 31(2), 224–245 (2013)
15.6
V.C. Kalia, H.J. Purohit: Quenching the quorum sensing system: Potential antibacterial
drug targets, Crit. Rev. Microbiol. 37(2), 121–140
(2011)
15.7
S. Kappuchery, D. Paul, J. Yoon, J.H. Kweon:
Vanillin, a potential agent to prevent biofouling of
reverse osmosis membrane, Biofouling 26(6), 667–
672 (2010)
15.8
J. Landoulsi, K.E. Cooksey, V. Dupres: Review – Interactions between diatoms and stainless steel:
Focus on biofouling and biocorrosion, Biofouling
27(10), 1105–1124 (2011)
438 Part B Tools and Methods in Marine Biotechnology
15.4.5 Engineered Bacteriophages
Phages that kill bacteria in a species-specific manner are
engineered to express the most effective EPS-degrading
enzymes specific to the target biofilm. This strategy
permits the development of a diverse library of biofilmdispersing phages rather than necessitating attempts
to isolate such phages from the environment. These
recombinant phages not only lyse the bacterial cells
rapidly but express and produce the biofilm-degrading
enzymes as well. This autocatalytic mechanism leads
to efficient removal of bacterial biofilms in a wide
range of scenarios, such as industrial, environmental,
and clinical settings [15.42]. This strategy also eliminates the need to produce, purify, and deliver large
doses of enzymes to target sites of infection that are otherwise difficult to access and would lead to improved
and efficient phage therapy for removal of biofilms. For
example, the engineered T7 phage expresses the K1-5
endosialidase enzyme, which allows it to replicate in the
K1 polysaccharide capsule –producing E. coli [15.42].
DspB hydrolyzes adhesions which are important in
the biofilm formation by several bacterial species, including clinical strains. Therefore, recombinant phages
producing DspB can be applied to a large number
of bacterial infections [15.42]. Also, several different
biofilm-forming bacterial species, including E. coli,
produce a group of biofilm promoting factors, required
to produce a mature biofilm. These factors are shared
among different strains and are, therefore, potential targets for an enzymatically engineered phage [15.42].
In contrast to most works which target only the
removal of biofilms and its associated bacteria, a recent approach was aimed at reusing the platform for
a fresh round of biofilms in biorefineries. Here, the
intention was to reuse the platform for chemical transformations. In the initial step, proteins, global regulator
(Hha) and cyclic diguanylate-binding (BdcA), were
engineered to disperse biofilms. The dispersal cells
were then removed through a chemical switch, isopropyl-ˇ-D-thiogalactopyranoside. This technique can
be applied to develop biosensors, biocorrosion, BF, and
bioremediation [15.43].
Recently, QQ has been applied as a practical solution to control BF of membrane bioreactors (MBR)
in water treatment systems. Cells of Rhodococcus
sp. BH4, a QQ bacterium, were entrapped in alginate beads (cell entrapping beads, CEB), and designed
with a porous surface microstructure. When these CEBs
were used in MBRs, a transmembrane pressure of
70 kPa was reached in a time period that was ten
times longer than MBRs without CEBs. The role of
CEBs was dual in controlling the biofilm formation:
biological, as quorum quenchers of AHLs produced
by BF bacteria, thus inhibiting the synthesis of extracellular polymeric substances involved in biofilm
formation, and physical as the source of friction between CEBs colliding with biofilm on the membrane
surface. Sloughing off of biofilm was more pronounced
with the QQ effect than friction. QQ is thus seen as
an efficient and economical alternative to control BF of
MBRs [15.44].
We should take inspiration from natural sources,
especially skins of marine animals and microbes associated with them to develop the most sustainable marine
technologies to control BF [15.9, 10].
References
15.1
D. Paul, Y.S. Kim, K. Ponnusamy, J.H. Kweon: Application of quorum quenching to inhibit biofilm
fermentation, Environ. Eng. Sci. 26(8), 1319–1324
(2009)
15.2
K.-M. Yeon, W.-S. Cheong, H.-S. Oh, W.-N. Lee, B.K. Hwang, C.-H. Lee, H. Beyenal, Z. Lewandowski:
Quorum sensing: A new biofouling control
paradigm in a membrane bioreactor for advanced
waste water treatment, Environ. Sci. Technol.
43(2), 380–385 (2009)
15.3
S. Dobretsov, M. Teplitski, M. Bayer, S. Gunasekra,
P. Proksch, V.J. Paul: Inhibition of marine biofouling by bacterial quorum sensing inhibitors,
Biofouling 27(8), 893–905 (2011)
15.4
M.P. Schultz, J.A. Bendick, E.R. Holm, W.M. Hertel: Economic impact of biofouling on a
naval surface ship, Biofouling 27(1), 87–98
(2011)
15.5
V.C. Kalia: Quorum sensing inhibitors: An overview,
Biotechnol. Adv. 31(2), 224–245 (2013)
15.6
V.C. Kalia, H.J. Purohit: Quenching the quorum sensing system: Potential antibacterial
drug targets, Crit. Rev. Microbiol. 37(2), 121–140
(2011)
15.7
S. Kappuchery, D. Paul, J. Yoon, J.H. Kweon:
Vanillin, a potential agent to prevent biofouling of
reverse osmosis membrane, Biofouling 26(6), 667–
672 (2010)
15.8
J. Landoulsi, K.E. Cooksey, V. Dupres: Review – Interactions between diatoms and stainless steel:
Focus on biofouling and biocorrosion, Biofouling
27(10), 1105–1124 (2011)