communities have been manipulated for the benefit of
mankind
With recent estimates giving a figure of 3.8·1013 microbes in a 70kg human body it is not surprising
that they play a huge role in our lives, inside and outside of our bodies. Some microbes can be life
threatening, however many others are of huge importance to our health as well as the global
economy. The vast differences between microorganisms means that they provide a wide range of
applications in our lives. From the microbes living on our skin and inside us, to pharmaceuticals and
food and drink products we have clearly evolved to rely heavily on them. They are the foundations
of some of the greatest scientific discoveries ever made. Consider the discovery of penicillin by
Alexander Fleming that has changed modern medicine, as well as vaccines that prevent diseases and
save millions of lives every year. In this essay I will be focusing on the pharmaceutical manipulation
of microbes, our microbiome and the effects of probiotics, bioremediation, and the cutting edge
CRISPR-Cas technologies recently discovered.
Pharmaceuticals
Microorganisms have been manipulated in many ways to create pharmaceutical products for our
benefit. Everyone has heard of penicillin – the fungus that can treat various infections. However,
there are many more examples of the use of microbes in medicine. Vaccines are one example of this,
as they are preparations of antigens that can be made with weakened pathogens which stimulate
the immune system to produce antibodies and provide immunity against the pathogen (Campbell et
al., 2017). Vaccines must go through rigorous trials that can go on for years before they can be
licenced and produced for the market (How are vaccines produced? | Vaccines Europe (European
Vaccine Manufacturers), no date).Vaccines are produced using microorganisms in several carefully
controlled steps: 1. Antigen preparation, 2. Release and isolation of the antigen, 3. Purification, 4.
Addition of other components, 5. Packaging.
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, Microbe uses are not limited to vaccines. Due to their diversity they are the base of many
pharmaceuticals. A more recent development is the use of cloned bacteria as part of cancer
treatment (Awan et al., 2015). The goal of cancer treatment is to eradicate tumour cells without
harming healthy cells. These bacteria have been modified to carry a drug-carrying gene or enzymes
to activate a prodrug that the bacteria release while replicating in the tumour. The hypoxic and
necrotic environment of cancer cells is the ideal environment for anaerobic bacteria (Zhou et al.,
2018). This necrotic tissue contains purines and chemo attractant compounds which helps the
growth of the bacteria and attracts them to the tumour site (Baban et al., 2010). Examples of
bacteria for which these techniques have been used are Salmonella typhi, Bifido bacterium, Vibrio
cholera, Listeria monocytogenes and Escherichia coli (Awan et al., 2015). These tumour-targeting
bacteria can greatly improve a cancer patient’s treatment due to their selectivity compared to many
other cancer treatments and will soon become one of the major cancer treatments widely available.
Probiotics
In my opinion, thanks to recent news articles and the influence of social media, we are becoming
increasingly aware of the importance of the human microbiome to our health and wellbeing. It has
been shown that the composition of our microbiome – especially our gut microbiome, effects many
parts of the body and has a direct link to our health (Gibson and Roberfroid, 1995) (see figure 1). It
has even been shown that the food we eat has a major impact on the microbial communities in our
gut which in turn has a great effect on our mental health (Opie et al., 2018). When our microbiome is
disrupted, for example by antibiotics, it is vital that it can be restored to full strength, which can be
done with probiotics (Fuller, 1991). When patients are treated with antibiotics, if they do not take a
probiotic supplement, they are at risk from infections from microorganisms such as Clostridium
difficile. Probiotics consist of several billion live beneficial microorganisms such as Saccharomyces
boulardii yeast and Lactobacillus lactic acid bacteria (Williams, 2010). They have several different
effects, depending on which microorganisms are used: lowering GI tract pH, decreasing the number
of pathogenic organisms present and improving the host’s immunity. Probiotics play a large part in
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