If you have an ACS member number, please enter it here so we can link this account to your membership. (optional)

ACS values your privacy. By submitting your information, you are gaining access to C&EN and subscribing to our weekly newsletter. We use the information you provide to make your reading experience better, and we will never sell your data to third party members.


Biological Chemistry

Probing Diversity-Generating Metabolic Pathways

Natural Products: In pathways that produce many different compounds, each step is slower than the ones before

by Celia Henry Arnaud
February 8, 2016 | A version of this story appeared in Volume 94, Issue 6

Unlike conventional metabolic pathways that lead to a single product, diversity-generating pathways produce many compounds. Understanding such diversity-generating pathways could help researchers develop combinatorial biosynthetic pathways. A team of researchers led by Baldomero M. Olivera and Eric W. Schmidt of the University of Utah shows how one such pathway from cyanobacteria differs significantly from conventional metabolic pathways. The researchers focused on the tru pathway, which synthesizes a diverse family of macrocyclic peptides called patellins (Proc. Natl. Acad. Sci. USA 2016, DOI: 10.1073/pnas.1525438113). To study the four-enzyme pathway, the researchers expressed it in Escherichia coli bacteria. They found that they could greatly increase the yield of patellins by adding cysteine, which releases hydrogen sulfide that modulates the enzymes’ activity. In the process of figuring out the cysteine effect, they learned that each step in the pathway is much slower than the preceding steps. This results in the accumulation of intermediates, which is in sharp contrast to conventional pathways, in which the first step is usually the rate-limiting step to avoid such accumulation.


This article has been sent to the following recipient:

Chemistry matters. Join us to get the news you need.