The lugdunin molecule in 3-D

The lugdunin molecule - rotatable in 3 dimensions

Lugdunin is an antibiotic, produced by Staphylococcus lugdunensis.
Details of this compound were released in July 2016 in a Nature article. It was also widely publicised in national newspapers.
However like any new candidate compound for medical use, it has yet to undergo some years of testing before it is generally available.

Molecular structure

Lugdunin is a cyclic peptide containing a thiazolidine group.
It consists of six amino acids joined by peptide linkages:
D-Val * .. L-Trp * .. D-Leu * .. L-Val * .. D-Val * .. [L-Val] *
* re-orientates the molecule, showing D/L status.
Several of these amino acids are D-forms, and their production involves nonribosomal peptide synthetase (NRPS) mechanisms. A cluster of four genes has been identified and a biosynthesis pathway has been proposed.
In fact the molecule starts out as a string of 7 amino acids. Cysteine - at the N-terminal end - is converted into the thiazolidine group, attached to the C-terminal L-valine after the heptapeptide cyclises to form the structure shown.
Label/ Unlabel atoms

Mode of action

No specific details have been published, but it seems likely that lugdunin works by interfering with bacterial cell wall biosynthesis.

Background to the discovery

Different people have different bacterial species inhabiting their nasal area (nostrils and sinuses). This effectively forms a sort of ecosystem in which bacterial species interact and compete with one another.
It was found by workers at the University of Tübingen, Germany, that some people have a bacterium Staphylococcus lugdunensis naturally inhabiting their noses, and that the antibiotic compound they produce is effective at controlling other Staphylococci.
Staphylococcus aureus is a widespread bacterium which may not present a problem in the nose but it may become a hazard after surgery. The strains called MRSA sometimes cannot be controlled in a medical context because of their resistance to the main antibiotics of the penicillin group, and lugdunin may be a useful alternative.
Moreover, other bacteria inhabiting the human body may represent a new source for antibiotics - most of which have previously been taken from soil-inhabiting micro-organisms.

Web references

Lugdunin From Wikipedia, the free encyclopedia

Human commensals producing a novel antibiotic impair pathogen colonization Alexander Zipperer, Martin C. Konnerth, Claudia Laux, Anne Berscheid, Daniela Janek, Christopher Weidenmaier, Marc Burian, Nadine A. Schilling, Christoph Slavetinsky, Matthias Marschal, Matthias Willmann, Hubert Kalbacher, Birgit Schittek, Heike Brötz-Oesterhelt, Stephanie Grond, Andreas Peschel & Bernhard Krismer