How we study microbes keeps us from realizing their potential benefits
Since Alexander Fleming discovered penicillin in 1928, high-value natural microbial products have been global commodities.
The world market for microbial products is projected to reach $346.3 billion in 2027.
It’s an astonishing amount of money — enough to make a serious dent in the global food crisis, for example — but there is a good reason humanity has come to place such a high value on these microscopic helpers.
To many, microbes mean only one thing: disease.
Microbes are not always harmful, though. We couldn’t live or live well without them.
These living organisms influence our world in ways humans could never have envisaged, let alone harnessed, until quite recently, and we are still just starting to understand and harness their power.
We use them to increase crop yields, to enhance, preserve and give life to our food in the case of bread, tofu, yogurt and many others, including beer and wine.
We deliberately seek probiotics to help keep ourselves healthy. We deploy microbes as invisible cleanup crews after oil spills, radioactive contamination and sustained industrial activity.
Earth is covered by microbes, which cluster into functional communities that interact as family, friends and foes, depending on local context.
Their social construct was beautifully illustrated by researchers Mary Davey and George O’Toole, who used the gut microbiome to show that microbes live in aggregates based mainly on their needs and functions.
Our digestive system, or gut, helps us to break down complex foods into usable elements. Among them, it turns starch into simple sugars, which most microbes in the gut depend on for energy.
While some microbes can further break down these sugars directly and use them as food, others stay close to microbes that can break down sugars and live off the byproducts of their processing, and still, other microbes live off the secondary processing of these byproducts.
Our orifices (mouth, nose, anus, urethra) and our skin all have unique microbe populations that act as the first lines of defence against infection. Pathogens must overcome these resident microbes before they can establish any infection.
The point here is that microbes are never alone, they exist in functional communities on any surface, including on our skin. If we were to culture a swab from any site on our skin, we would likely be able to grow and identify multiple individual colonies of microbes. Studying them one colony at a time, though, would not only take time and resources. It would miss what’s most important: their function within the specific environment from which they had been isolated.
Microbes communicate with members within a community through chemical signals that other microbes decode and use to guide their behaviours.
The communication of microbes among themselves and with other microorganisms around them can be both detrimental and beneficial to us as humans.
This is clearly shown in the balance of microbial communities on the surface of healthy skin, which is an indication of a healthy co-ordination of activities among diverse microbes.
For example, the bacteria Staphylococcus aureus is notorious for its ability to cause a wide array of skin diseases.
Skin predominantly covered with Staph. aureus often appears unhealthy, as in dermatitis, but scientists have shown that growing Staph. aureus with its “cousin,” Staphylococcus epidermidis, makes it less dangerous, because of certain Staph. epidermidis compounds which reduce the harmful effects of Staph. aureus.
A recent study of multiple bacteria living together led to the discovery of a novel antibiotic, amycomicin, which kills S. aureus, suggesting that exploring other interactions of multiple microbes could produce other significant discoveries.
Since microbes behave differently in different settings, studying them in isolation limits our understanding of their combined functions, hampering the potential for innovative discoveries.
A complex but systematic approach can lead to novel discoveries that improve our health while also paying for themselves by generating economic impact.