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One
thing that can be stated about microbes, and in general, about the life
unseen around us...is that it is always adapting. So yes, the potential
is always there.
Just
as a baby changes slowly into a toddler, living organisms are constantly
changing to adapt to their environment. These changes are called mutations.
Since a single microorganism can multiply into billions in a day’s time
or less, they have great adaptive ability.
Bacteria
constitute the most successful form of life in environmental habitats.
The main reason for this success is phenotypic plasticity. It is the ability
of a bacterial genotype to respond phenotypically to environmental stimuli,
rather than the power of its genetic repertoire, that has produced the
extensive development of bacteria. A general phenotypic strategy has little
by little become apparent in many bacterial strains, as we have come to
understand more of the lifestyle that these organisms are able to adopt
in response to changing growth conditions.
Another
concern in drinking water is the rise of old diseases in combination with
new biotechnology methods, leaving the possibility for new, and as of
yet, not researched combinations of bacteria. According to the 1996 WHO
Report, the world is heading for a major crisis in public health as outbreaks
of new and re-emerging infectious diseases are striking at increasing
frequencies within the past 10 to 15 years. The current strains of pathogens
are moreover, resistant to known treatments; some strains being resistant
to all or nearly all drugs and antibiotics. Horizontal gene transfer is
now generally recognized to be responsible for the evolution of virulence
and the spread of drug and antibiotic resistances. Many pathogens have
crossed species barriers, having acquired genes from phylogenetically
distant species that are involved in their ability to cause diseases.
Recent findings document the extremely wide scope of horizontal gene transfer
and the extensive recombination between genetic material from unrelated
species that have contributed to the emergence of virulence and antibiotic
resistances. The past 15 years coincide with the development of genetic
engineering biotechnology on a commercial scale. Genetic engineering depends
on designing vectors for cloning and transferring genes and involves artificially
recombining and manipulating genes from unrelated species and their viral
pathogens, thereby enhancing the probability for horizontal gene transfer
and recombination.
Recent
studies indicate that common protozoa and bacteria that line in water, without the influence
of bioengineering, have tremendous
adaptive potential due to mutations. When their environment changes, even
inactive genes may become active, resulting in new characteristics. Therefore,
if source water quality is allowed to deteriorate, common microbes previously
considered harmless, may become pathogenic due to adaptive mutations.
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