Their result, reported today in Nature (DOI: 10.1038/nature10865), details how a soil bacterium, Streptomyces lasaliensis, is able to convert an epoxide into a six-membered cyclic ether during synthesis of lasalocid, a natural polyether antibiotic. The fact that bacteria can perform such chemistry has puzzled chemists and biologists for decades because this type of chemical transformation is known to be kinetically unfavorable.
According to "Baldwin's Rules for Ring Closure," which govern the way these rings form, lasalocid should contain a five-membered ring instead of the observed six-membered ring.
According to "Baldwin's Rules for Ring Closure," which govern the way these rings form, lasalocid should contain a five-membered ring instead of the observed six-membered ring.


