In addition, the leakage and industrial discharge of petrol and their associated
chemicals like polycyclic aromatic hydrocarbons (PAH) pose a highly negative
impact on aquatic and terrestrial ecosystems. Genetically modified organisms
(GMOs) have a capability to clean up and remove industrial waste and pollutants
from the environment as well as reduce toxicity of elements (Liu et al. 2011).
Genetic engineering is currently popular among researchers worldwide to
develop new microbes with required traits as compared to its wild type for the
degradation and detoxification of a wide range of xenobiotic compounds (Kumar
et al. 2013).
In 1970, the first GMOs called “superbug” were developed by genetic engineering through plasmid transfer that have ability to degrade a variety of petroleum
chemicals such as xylene, camphor, hexane, naphthalene, and toluene. GMOs are
capable for enhanced degradation and removal of a wide range of xenobiotic and
also have potential application for bioremediation of environmental pollutants
(Kulshreshtha 2013). Designing of GMOs primarily depend on the knowledge of
genetic basis of interaction between microbes and xenobiotic compounds, structure
of operon, molecular biology, biochemistry, and ecology (ref). Thus, GMOs can be
potential molecular tools to degrade and detoxify the environmental pollutants in
contaminated matrix to safeguard the environment and public health. Therefore, this
chapter has mainly focused on the role of GMOs in the bioremediation of organic
and inorganic pollutants, constraints in utilizing them in bioremediation, and limitations in field applications.
2 Genetically Modified Organisms
Designing of suitable genetically modified organisms (GMOs) for enhanced bioremediation of environmental pollutants from contaminated matrix requires creation of new
routes for metabolism, intensifying a range of existing degradation pathways, avoiding
substrate misrouting into unproductive routes or to toxic metabolite generation,
improving the substrate flux through degradation pathways to avoid the accumulation
of toxic intermediates, enhanced stability of catabolic potential, enhanced bioavailability of hydrophobic pollutants, and enhanced catabolic potential of microbes
(Timmis and Pieper 1999; Pieper and Reineke 2000; Furukawa 2003).
Although an organism produced from genetic engineering techniques allows
the transfer of specific functional genes into a particular organism genome (Tozzini
2000). A US definition of GMO, “genetically modified organisms,” refers to microorganism, plants, and animals containing distinctive genes transferred from other
species to produce unique characteristics to completely clean up and mineralize
hazardous waste material. Many bacterial strains such as Bacillus idriensis,
Ralstonia eutropha, Sphingomonas desiccabilis, Pseudomonas putida, Escherichia
coli, Mycobacterium marinum, etc. have been used to design genetically engineered
microbes with insertion of a functional gene into other species which capable for the
bioremediation of heavy metals and non-biodegradable compounds of contaminated
1 Genetically Modified Organisms (GMOs) and Their Potential in. . .
3
chemicals like polycyclic aromatic hydrocarbons (PAH) pose a highly negative
impact on aquatic and terrestrial ecosystems. Genetically modified organisms
(GMOs) have a capability to clean up and remove industrial waste and pollutants
from the environment as well as reduce toxicity of elements (Liu et al. 2011).
Genetic engineering is currently popular among researchers worldwide to
develop new microbes with required traits as compared to its wild type for the
degradation and detoxification of a wide range of xenobiotic compounds (Kumar
et al. 2013).
In 1970, the first GMOs called “superbug” were developed by genetic engineering through plasmid transfer that have ability to degrade a variety of petroleum
chemicals such as xylene, camphor, hexane, naphthalene, and toluene. GMOs are
capable for enhanced degradation and removal of a wide range of xenobiotic and
also have potential application for bioremediation of environmental pollutants
(Kulshreshtha 2013). Designing of GMOs primarily depend on the knowledge of
genetic basis of interaction between microbes and xenobiotic compounds, structure
of operon, molecular biology, biochemistry, and ecology (ref). Thus, GMOs can be
potential molecular tools to degrade and detoxify the environmental pollutants in
contaminated matrix to safeguard the environment and public health. Therefore, this
chapter has mainly focused on the role of GMOs in the bioremediation of organic
and inorganic pollutants, constraints in utilizing them in bioremediation, and limitations in field applications.
2 Genetically Modified Organisms
Designing of suitable genetically modified organisms (GMOs) for enhanced bioremediation of environmental pollutants from contaminated matrix requires creation of new
routes for metabolism, intensifying a range of existing degradation pathways, avoiding
substrate misrouting into unproductive routes or to toxic metabolite generation,
improving the substrate flux through degradation pathways to avoid the accumulation
of toxic intermediates, enhanced stability of catabolic potential, enhanced bioavailability of hydrophobic pollutants, and enhanced catabolic potential of microbes
(Timmis and Pieper 1999; Pieper and Reineke 2000; Furukawa 2003).
Although an organism produced from genetic engineering techniques allows
the transfer of specific functional genes into a particular organism genome (Tozzini
2000). A US definition of GMO, “genetically modified organisms,” refers to microorganism, plants, and animals containing distinctive genes transferred from other
species to produce unique characteristics to completely clean up and mineralize
hazardous waste material. Many bacterial strains such as Bacillus idriensis,
Ralstonia eutropha, Sphingomonas desiccabilis, Pseudomonas putida, Escherichia
coli, Mycobacterium marinum, etc. have been used to design genetically engineered
microbes with insertion of a functional gene into other species which capable for the
bioremediation of heavy metals and non-biodegradable compounds of contaminated
1 Genetically Modified Organisms (GMOs) and Their Potential in. . .
3