PT  - JOURNAL ARTICLE
AU  - Kominek, Jacek
AU  - Doering, Drew T.
AU  - Opulente, Dana A.
AU  - Shen, Xing-Xing
AU  - Zhou, Xiaofan
AU  - De Virgilio, Jeremy
AU  - Hulfachor, Amanda B.
AU  - Kurtzman, Cletus P.
AU  - Rokas, Antonis
AU  - Hittinger, Chris Todd
TI  - Eukaryotic Acquisition of a Bacterial Operon
AID  - 10.1101/399394
DP  - 2018 Jan 01
TA  - bioRxiv
PG  - 399394
4099  - http://biorxiv.org/content/early/2018/08/24/399394.short
4100  - http://biorxiv.org/content/early/2018/08/24/399394.full
AB  - Operons are a hallmark of bacterial genomes, where they allow concerted expression of multiple functionally related genes as single polycistronic transcripts. They are rare in eukaryotes, where each gene usually drives expression of its own independent messenger RNAs. Here we report the horizontal operon transfer of a catecholate-class siderophore biosynthesis pathway from Enterobacteriaceae into a group of closely related yeast taxa. We further show that the co-linearly arranged secondary metabolism genes are actively expressed, exhibit mainly eukaryotic transcriptional features, and enable the sequestration and uptake of iron. After transfer to the eukaryotic host, several genetic changes occurred, including the acquisition of polyadenylation sites, structural rearrangements, integration of eukaryotic genes, and secondary loss in some lineages. We conclude that the operon genes were likely captured in the shared insect gut habitat, modified for eukaryotic gene expression, and maintained by selection to adapt to the highly-competitive, iron-limited environment.