Bacteria are indispensable to life. Just look at how useful they are in our bodies and how they are part of our daily diet. In other areas bacteria have proven to be useful as well: in healthcare, agriculture, industrial processes and the environment. Biotechnology uses bacteria to produce biological substances that are useful to us. They are able to create fuels, drugs, hormones, enzymes, proteins and nucleic acid. The potential of biotechnology is endless when you look at the genetic abilities of bacteria!
Vaccines against diseases, antibiotics to fight diseases and probiotics that improve our health, are all made with bacteria. Biotechnology is also used to produce proteins and peptides. The use of bacteria for the production of medicines is known as red biotechnology.
Bacteria are particularly useful critters in agriculture too. For example, they play an important role in fertilisation. Plants do not feed on organic fertilisers but on minerals. Ammonia, which is produced from animal waste, is converted to nitrites by bacteria. Other bacteria convert these nitrites to nitrates that can ultimately serve as fertiliser for plants. The use of bacteria in sustainable agriculture has become indispensable.
Lactic acid bacteria allow animal feed to be kept longer. The feed is ensiled, similar to the human storage technique. A biochemical process in the pit heap will start. The lactic acid bacteria convert the sugars in the feed to lactic acid. After a while, this ensures a stable acidity with a longer preservation time as a result.
Bacteria are also used to prevent damage by insects and vermin. Pest control by natural enemies is called biological pest control. The bacterium Bacillus thuringiensis for example, is a toxic substance that kills many insects. Some fungi, such as Verticillium lecanii, can also kill insects.
This is called green biotechnology.
White biotechnology consists of all industrial processes, which involves enzymes, bacteria and fungi. You name it and microorganisms do it: bleaching paper, washing your clothes, cleaning your contact lenses, stonewashing your favourite jeans, tanning leather,…
We encounter bacteria in everyday life where we don’t expect them. Bacteria help us cleaning our washing. Detergents are a combination of soap and enzymes, which are derived from microorganisms. The enzymes break down the dirt so that residues can be washed away without having to be encapsulated by soap. Thanks to the enzymes your laundry is clean faster, less water has to be used and the water that is used can be less warm.
Wood pulp, the raw material of paper, contains a substance that causes a brown colour. Unbleached paper is browner than the bleached variety. In order to bleach the paper, enzymes from wood fungi can be used. In nature, tree trunks on which these enzymes live, fade. Once on paper, they bleach the wood pulp.
In olden days man used excrement to remove fat and tissue of leather (tanning). The enzymes from the faecal bacteria were they key to achieving this. Today these enzymes are only used for large-scale tanning.
As you can see, bacteria have a beneficial effect on the environment. Microorganisms do even more: they clean the environment by purifying water, recycling and processing waste. They are also used to create clean alternatives such as biogas.
Did you know microorganisms are used in wastewater treatment plants? After the physical purification, namely the removal of large particles such as coarse dirt, oil and sand, the biological treatment follows. In this stage organic material, like human faeces, is broken down. Bacteria use this organic material as nutrients. By adding oxygen microorganisms can effectively break down the organic waste load.
Bacteria can generate renewable energy, such as biogas. Biogas is a gaseous mixture arising from a biological enzymatic process. By fermenting organic material in an oxygen-free environment such as manure, sewage sludge from wastewater treatment plants or landfill garbage gas is created. Swamps and marshes form natural biogas too.
Biogas consists mainly of methane and carbon dioxide. It can be used for cooking or to generate electricity.
Recycling and processing waste
Bacteria and fungi inside the waste itself break down organic waste. A large proportion of domestic waste is composed of organic material. It means it can be processed into compost. During this process, additionally biogas is generated.
The bacterium Dehalococcoides ethenogenes can break down organochlorine compounds in contaminated groundwater and there are bacteria that can clean up toxic substances such as pesticides.
There is a recycling process that uses bacteria for the degradation of PET bottles. The Pseudomonas bacterium produces polyhydroxyal-kanoate or PHA when it feeds on PET components. PHA plastic is biodegradable.
A 16-year-old student in Canada even discovered a combination of bacteria that can degrade plastic bags in water with a little bit of added CO2.
Life on Earth
We are nowhere near knowing everything about bacteria and there is much to still discover about these little multitaskers. What we do know is that they are extremely powerful and ensure life on earth.