An article published in the journal “Nature Communications” reports the production of sulfated chondroitin by biosynthesis thanks to genetically modified bacteria of the type Escherichia coli. A team of researchers used a variant of the various CRISPR gene editing techniques called CRISPRi (CRISPR interference) to obtain what, combined with glucosamine, is considered a valid supplement in the treatment of some forms of osteoarthritis. Chondroitin sulfate is normally obtained from the cartilages of animals such as cows, so the ability to generate it using bacteria would offer an ethical and sustainable alternative.
Sulfated chondroitin, or chondroitin sulfate, is part of a group of compounds called glycosaminoglycans (GAGs). In this case, it’s a glycosaminoglycan sulfate. Other molecules of this class are important in the pharmaceutical and nutraceutical fields and are currently extracted from animal tissues. In these cases, there are ethical problems related to the exploitation of the species used for this purpose but there are also practical problems related to the availability of tissues and the dangers of contamination of these compounds during the extraction processes. This study offers a potential ethical and sustainable alternative.
Modifying a bacterium of the type Escherichia coli hasn’t been easy even though it’s often used for such purposes using various CRISPR techniques to modify its genome. This result is far from simple, and to achieve it three professors joined forces: Mattheos Koffas and Jonathan Dordick, professors of chemistry and biological engineering at Rensselaer Polytechnic Institute in Troy, New York, in the USA, and Robert Linhardt, professor of chemistry and chemical biology in the same institute. These are researchers who already have experience in this type of research. Linhardt is an authority on heparin, another glycosaminoglycan sulfate used as an anticoagulant drug, currently obtained from pig intestines, and has already worked on alternatives to its production.
Getting the Escherichia coli bacteria to produce sulfated chondroitin was a complex task that required several attempts. Success offers new possibilities to obtain this compound without using animal tissues and with great purity. Escherichia coli thrives under laboratory conditions and it shouldn’t be very difficult to get them to replicate in amounts sufficient to produce sulfated chondroitin in practical amounts.
Bringing a technique from the laboratory to real production is always difficult and makes all the difference between an experiment and a practical application of a technique. In this case, the bacteria used are easy to use, so the possibilities are really interesting also to produce other compounds such as heparin.
