What does this bacterium look like?
Clostridium is a rod that varies in length from 1 to more than 10 micrometers. That is small when you know that 1,000 micrometers fit into one millimeter. This bacterium has a thick cell wall. Some species are motile because they have flagella. A flagellum is nothing less than a tail that rotates very quickly to propel the bacterium forward. This is similar to the propeller of a submarine. 😉
What does science already know about this bacterium?
Quite a lot. The genus Clostridium was first described in 1880 and now includes more than 150 recognized species. Some species are commonly known as pathogens, such as Clostridium botulinum and Clostridium difficile. The first species produces the toxin botulinum, which causes muscle paralysis, also known as botulism. As you may notice from this name, this toxin is included in botox injections. On the other hand, the second species can cause severe diarrhea and intestinal inflammation (such as colitis) after antibiotic treatment. But there is certainly no reason to panic. In recent years, scientists have discovered that there are also many Clostridium species with beneficial properties (such as Clostridium leptum and Clostridium butyricum) and that pathogenic species do not always behave badly.
What makes Clostridium so special is that this bacterium can form spores. Spores are a kind of survival capsule that can withstand extreme conditions, such as heat or drought. The name Clostridium comes from the Greek “klôstêr”, which means “spool”. Under the microscope, this bacterium sometimes resembles a spool used in weaving cloth.
We also know that Clostridium has a genome of approximately 2.5 to 6 million base pairs with more than 2,000 genes. This means that this bacterium can produce more than 2,000 different substances.
What is this bacterium doing in my gut?
Clostridium is an important gut inhabitant. This bacterium uses food residues that you cannot digest yourself, such as fiber from fruit and vegetables. When Clostridium gets to work, it converts these food residues into useful substances. Butyrate is one of the substances that Clostridium can produce or generate. This immediately explains where the species Clostridium butyricum gets its name from. 😉
What is butyrate? It is a short-chain fatty acid that nourishes the intestinal wall (or intestinal lining) and thus ensures a good intestinal barrier. This makes it more difficult for harmful substances to leak through the intestinal wall. Butyrate is also able to inhibit inflammation. This is one way in which Clostridium strengthens the immune system in your gut.
Did you know that vitamin B2 or riboflavin also plays an important role here? Some Clostridium species can produce riboflavin themselves. Clostridium acetobutylicum was already being used in 1946 for the large-scale production of riboflavin (for example, for the development of supplements). In our VIAB2L study, riboflavin plays a central role. Here, we can further investigate the role of Clostridium and its riboflavin production in the gut. Interesting! 🙂
And there’s more: some Clostridium species are central to the development of “new generation probiotics” or “Live Biotherapeutic Products” (LBPs). What are probiotics? Probiotics are live microorganisms that confer a health benefit on the host when administered in adequate amounts.
Here are a few examples:
- The company Vedanta Biosciences is developing consortia (bacteria that work together as a team) with strains from different Clostridium clusters (as in their product VE303) to prevent recurrent infections with Clostridioides difficile and support the immune system.
- Seres Therapeutics has launched SER-109, an approved product based on purified spores of Clostridium species, and is further investigating another product (SER-155) for immune recovery.
- Rebiotix (Ferring Pharmaceuticals) is working with RBX2660, a product based on different Clostridium strains that together help to suppress the pathogenic Clostridioides difficile.
- The Belgian company MRM Health focuses on stable consortia with different Clostridium species, such as in their MH002 program for inflammatory bowel diseases, which focuses on butyrate production and modulation of the immune system.
It is becoming clear that Clostridium bacteria play a key role in the development of LBPs. Whether these will soon be marketed as medicines in Europe and Belgium remains to be seen. 🙂
Does this bacterium occur elsewhere?
Researchers have also found this bacterium in the intestines of other mammals, such as cows and sheep. Although Clostridium thrives in the oxygen-poor environment of the intestine, this bacterium also occurs in other places outside the human body. This is partly due to its ability to form spores. Clostridium can also be found in soil and water.