Venom of a Snake Kills Bacteria Without Affecting Healthy Cells

An international investigation led by Professor Pompeu Fabra University (UPF) of Barcelona David Andreu has discovered that a peptide from the venom of a South American rattlesnake, crotalidicin, kills bacteria without affecting healthy cells.
The finding, published in the Journal of Biological Chemistry, opens the possibility that there is an alternative to conventional antibiotics to which many bacteria are becoming resistant which can help doctors from different areas from pediatrics to dentists in Tijuana.
According to Andreu, who is the head of the Protein Research and Protein Chemistry Research Group at UPF, the study has shown that the crotalidicin peptide fragment is directed to the surface of the bacteria by electrostatic attractions, caused by differences in the properties of the membranes.
This is because, according to the work, the peptide is positive while the bacteria is negative, which allows it to kill the bacteria when it is inserted into the membrane and how the cells of the body that host the infection have neutral membranes are not affected .
The first author of the work and currently a PhD candidate in David Andreu’s team at UPF, had previously discovered that the fragment retained the antimicrobial potency of the entire peptide but was harmless to non-bacterial cells, and also very resistant to serum proteases, a property not usual in peptides and very promising in the face of pharmacological application.
The investigation was carried out on strains of bacteria among which there are some of those that cause serious infections in hospitals, which are usually difficult to attack because they have an extra membrane and are often camouflaged by a protective capsule.
“The results point to a promising role for this fragment of cathelicidin, and continue to confirm that the peptides, properly redesigned, are effective antibiotics against resistant bacteria,” summarized David Andreu.
The work has involved researchers from Australia, Portugal, Brazil and France, in a program of exchange of research and innovation personnel funded by the European Commission in the Horizon 2020 framework.
Thanks to this program that allows mobility and knowledge transfer between institutions, Clara PĂ©rez-Peinado has been able to make a long stay at the Institute of Molecular Medicine of the University of Lisbon, and David Andreu and Sira Defaus, from the same laboratory, stays of six months at the IMB in Brisbane (Australia).