If there is one field of investigation that is today the subject of fierce exploration by scientists, it is undoubtedly that of bacteria, especially as they show themselves – and in a disturbing way – increasingly resistant to antibiotics. The many recent hospitalizations of patients weakened by Covid have also led to an upsurge in bacterial infections, which seem to have taken advantage of the opportunity to gain ground. Hence the interest and the urgency to find solutions to face them in the future.
Determined to better understand the mechanism and the role played by bacteria, a team from UCLouvain has just made a new discovery in this area, published this Thursday in the prestigious scientific journal. Nature Chemical Biology. They have indeed identified unstructured segments, still unexplored to date, in proteins. Shaped like soft spaghetti, these segments are essential to the life of bacteria.
Invaders and perimeter walls
“To fight your enemy, you have to know your strengths and weaknesses, understand how this enemy is upgrading its weapons”, explains Prof. Jean-François Collet, researcher at the Institut de Duve at UCLouvain and WELBIO investigator. Understand how bacteria work, decipher their mechanisms in order to thwart their resistance to antibiotics, this is precisely the objective of his laboratory and of present research.
To understand them properly, you should know that bacteria protect themselves from “invaders”, in this case antibiotics, thanks to one or two membranes, which could be compared to perimeter walls. In addition, “they are made up of proteins: each has its own structure that determines its function, explain the researchers. In the outer protective wall, lipoproteins are found in particular, i.e. proteins attached to the wall via a lipid (fatty) anchor. These lipoproteins participate in the construction of the wall, its maintenance and its defense, thus allowing the bacteria to live and conquer“.
Like a cooked spaghetti, very soft …
The UCLouvain team, including the young researcher Jessica El Rayes, observed that between the active part of the lipoprotein and the lipid part, there is actually a sequence without structure, which looks like … “a cooked spaghetti, very soft, able to adopt the shape it wants“.
Curiously ignored so far by research, these destructured sequences are nevertheless present in many bacteria such as E-coli or Borrelia (Lyme disease). Reason why Prof. Collet’s team decided to investigate this soft segment, in order to determine its role in life. bacteria.
This is how scientists discovered that “the bacteria were weakened when transforming the “soft spaghetti” in spirelli or when shortened to angel hair“, they explain. In other words, they demonstrated the essential role of this disorderly sequence : “without this soft spaghetti, the lipoproteins no longer reach the perimeter wall and the bacteria are therefore weakened!”
This important discovery highlights the fact that there are still many mysteries in this area and many regions to be explored within proteins. So many answers to be provided that will be necessary for the essential development of new antibiotic treatments intended to fight bacterial infections.