Discovering microbes

Answers provided by

• Professor Nicola Stanley-Wall FRSE
• Professor Sarah Coulthurst FRSE
• Professor J. Ross Fitzgerald FRSE
• Professor Paul Hoskisson FRSE
• Professor Malcolm White FRSE
• Professor Matthew Holden FRSE

How were microbes first discovered?

Microbes were first discovered by a Dutch scientist named Antonie van Leeuwenhoek in the 1670s. He made a microscope and looked at water, teeth scrapings, and a whole range of other things. He saw tiny living creatures he called “animalcules,” which we now know as bacteria and other microorganisms. His discovery showed that there are tiny, invisible life forms all around us. This was a huge surprise and helped start the field of microbiology, the study of these tiny organisms.

Why are microbes called microbes?

The term “microbes” literally refers to tiny living things (organisms) or such as bacteria, viruses, fungi, and some protozoa that can only be viewed with the aid of a microscope. They have therefore been given the general name microorganisms which can be shortened to microbes

How do scientists dye the microbes so they can see them better?

Scientists dye microbes to see them better by using special stains. Microbes are very tiny and often clear, so stains help make them visible under a microscope. The stains are colourful chemicals that attach to different parts of the microbes, highlighting their shapes and structures. For example, one common stain is called Gram stain, which helps scientists tell different types of bacteria apart by staining them purple or pink depending on the type of outer surface they have. By applying these stains, scientists can study the microbes more easily and learn more about them.

Have new microbes been discovered recently?

Microbes are constantly being discovered, with thousands of new types discovered by scientists every year. We can find microbes everywhere on earth, from the bottom of the deepest oceans to the top of the highest mountains. They can also live in deserts, in hot springs and caustic lakes, where few other living things can survive. We are getting better at discovering new microbes and we don’t even have to be able to grow them in the laboratory anymore, we can find them by just looking for their DNA in environments where they might be.

How much bacteria can fit into 1 squared cm?

The answer is a lot! The exact number depends on the environment and the type of bacteria, as they are not always packed tightly together, and their shapes and sizes vary. For one of the bacteria that scientists study the most (called ‘E. coli’), about 50 million bacteria could squeeze together into one square centimetre.