Expression and genetic activation of cyclic di-GMP-specific phosphodiesterases in Escherichia coli

Alberto Reinders, Chee Seng Hee, Shogo Ozaki, Adam Mazur, Alex Boehm, Tilman Schirmer, Urs Jenal

Research output: Contribution to journalArticlepeer-review

14 Citations (Scopus)

Abstract

Intracellular levels of the bacterial second messenger cyclic di-GMP (c-di-GMP) are controlled by antagonistic activities of diguanylate cyclases and phosphodiesterases. The phosphodiesterase PdeH was identified as a key regulator of motility in Escherichia coli, while deletions of any of the other 12 genes encoding potential phosphodiesterases did not interfere with motility. To analyze the roles of E. coli phosphodiesterases, we demonstrated that most of these proteins are expressed under laboratory conditions. We next isolated suppressor mutations in six phosphodiesterase genes, which reinstate motility in the absence of PdeH by reducing cellular levels of c-di-GMP. Expression of all mutant alleles also led to a reduction of biofilm formation. Thus, all of these proteins are bona fide phosphodiesterases that are capable of interfering with different c-di-GMP-responsive output systems by affecting the global c-di-GMP pool. This argues that E. coli possesses several phosphodiesterases that are inactive under laboratory conditions because they lack appropriate input signals. Finally, one of these phosphodiesterases, PdeL, was studied in more detail. We demonstrated that this protein acts as a transcription factor to control its own expression. Motile suppressor alleles led to a strong increase of PdeL activity and elevated pdeL transcription, suggesting that enzymatic activity and transcriptional control are coupled. In agreement with this, we showed that overall cellular levels of c-di-GMP control pdeL transcription and that this control depends on PdeL itself. We thus propose that PdeL acts both as an enzyme and as a c-di-GMP sensor to couple transcriptional activity to the c-di-GMP status of the cell.

Original languageEnglish
Pages (from-to)448-462
Number of pages15
JournalJournal of bacteriology
Volume198
Issue number3
DOIs
Publication statusPublished - 2016
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Microbiology
  • Molecular Biology

Fingerprint Dive into the research topics of 'Expression and genetic activation of cyclic di-GMP-specific phosphodiesterases in Escherichia coli'. Together they form a unique fingerprint.

Cite this