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The new bacterial frontier

Since the 1970s, the number of new antibiotics discovered has fallen dramatically. At the same time, the increasing incidence of nosocomial infections (infections that are contracted in hospitals) proves that today's antibiotics are unable to fight certain resistant pathogenic microorganisms. In 2001, Renaud Nalin, a researcher at the Microbial Ecology Laboratory in Lyon,1 tackled the problem head-on by creating Libragen, a biotech company with the initial goal of identifying new antibiotic molecules derived from microorganisms. Today, the Toulouse-based company has hit its stride; it has identified around a hundred bacteria capable of producing new antimicrobial and antiproliferative agents.


While the company does have competition on the pharmaceutical market, its know-how for identifying “candidate bacteria” is unique. Just eighty years after Alexander Fleming observed their inhibiting and competitive activity, less than 5% of all existing microorganisms have been tested for making drugs. Why so few? Because the remaining 95% are very difficult to isolate and grow, two essential steps in testing the molecules which these microorganisms are able to produce. In order to access this bacterial bio-resource, Libragen's twelve employees circumvented the obstacle of microbiological isolation and growth.


“Starting with an environmental sample (earth, water, animal, or vegetal), we gather the bacteria regardless of whether or not they can be cultivated. We process them in order to extract large pieces of genomic DNA which we inject into a cultivable host bacteria. The host bacteria carrying a gene coding for an active molecule can then be produced in large quantities through simple fermentation,” explains Fabrice Lefèvre, an expert in molecular biology and protein engineering who recently joined the Libragen team.


In theory, this process (covered by four patent groups, one of which was granted in the US) is simple but still relatively complex in practice. “The discovery of a new antimicrobial or anticancer molecule from a sample requires two to four months of research before its spectrum of activity can be established via a series of tests.”

The company currently has a bank of some 500,000 bacteria prepared and ready for testing. In the past two years, Libragen has developed new partnerships in the area of biocatalysis, the catalysis of chemical reactions with the help of enzymes. Enzymes, which are true biological catalysts, enable more precise and cleaner reactions than synthetic chemicals. For this type of research, Libragen has developed over the past year a technological platform in Toulouse in collaboration with the National Institute of Applied Sciences (Insa). This new activity has enabled Libragen to expand its range of activity toward cosmetics and fine chemistry. In the future, the company is set on developing further medical applications by looking for molecules with antifungal and anti-inflammatory properties.


Aude Olivier

Notes :

1. Laboratoire d'Ecologie Microbienne (CNRS / Université Lyon-I joint lab).

Contacts :

> Fabrice Lefèvre
Libragen, Toulouse.

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