Get to know Lactobacillus isalae: the first official Isala baby bacterium

Woohoo! Thanks to the vaginal swabs of our Isala participants, we discovered a completely new bacterial species in the vagina! It was up to us to name this new bacterium ourselves and we called it Lactobacillus isalae. With this, we wanted to honor Isala Van Diest, but the scientists reviewing our proposal emphasized that we should also highlight our Isala project in the description. Quite an honor! This wasn’t possible without our amazing participants. Keep on reading to discover more about this new vaginal bacterium and the scientific article dedicated to it! 😊

How did we find this new species? After the sampling campaign, not only DNA analyses were performed but we also actively worked on cultivating bacteria from the swabs, and we’re still doing that. We’ve managed to cultivate around 3000 different vaginal bacteria. That’s a big success!

How do we do that? The content from the swab is carefully put on a petri dish with a growth medium because bacteria, just like us, need nutrients to grow. A few days later we check if the bacteria have grown enough, and if we can see the colony with the naked eye. A colony is a group of the same bacteria that together form a visible ‘dot’ (see picture). Then, we can identify these grown bacteria to get a better idea of which bacteria we are dealing with. We use a specific piece of DNA for that, the 16S-rRNA gene. This helps us understand the genus of this bacterial colony. You can compare it to distinguishing different dog breeds, but without knowing the exact species, like a dog, a wolf, or a coyote.

After identifying the bacteria, we examine their characteristics. We study how well they grow, how much acid they produce, and how effectively they can inhibit harmful microorganisms. As you know, we love lactobacilli because of their health-promoting properties. We aim to meet the best of these bacteria, so we unravel their complete DNA code. By comparing that DNA with known bacteria, we discovered a new bacterial species. Coming back to the analogy from above: here we are not talking about a wolf or a dog but discovering a completely new species that had never been described before.

This was a very exciting discovery for us as microbiologists! We reacted equally excited as macro-biologists that discover a new animal or plant species in the jungle that no one has seen before. Of course, we thoroughly examined this new bacterial species. For example, we found that this bacterium can use fewer types of sugars to grow compared to the related species Lactobacillus gasseri, suggesting it’s more adapted to life in the vagina.

Our first Isala bacterial species, how cool! Now, we are extra motivated to discover more in the unique Isala collection. To be continued! #LetsSwab