Kai Papenfort | Professor for Microbiology, Ludwig-Maximilians University

papenfort-180x180Kai Papenfort finished his undergraduate studies in biology in 2005 at the Phillips University in Marburg, Germany.

In 2006 he moved to the UK to work as a Marie Curie fellow at the Institute of Food Research in Norwich where he studied small RNAs in Salmonella Typhimurium. After that, he returned to Germany to receive his PhD in 2010 in Genetics/Microbiology at the Humboldt University, Berlin. Since his PhD, he has worked as a postdoctoral research fellow with Jörg Vogel at the Institute for Molecular Infection Biology in Würzburg (Germany) and with Bonnie Bassler at Princeton University (USA).

In 2015, he was appointed as Professor of Microbiology at the Ludwig-Maximilians-University of Munich, Germany. Work in his group focuses on gene regulation by bacterial noncoding RNA molecules and intercellular communication among microbes.

From Strings of Nucleotides to Collective Behavior: “Lessons from Vibrio cholerae”

Quorum-sensing (QS), is a process of bacterial cell-to-cell communication that relies on the production, release, and population-wide detection of extracellular signal molecules. Processes controlled by QS are unproductive when undertaken by an individual bacterium but become effective when undertaken by the group. QS controls many important microbial processes including bioluminescence, secretion of virulence factors, competence and biofilm formation. In this study, we identified and characterized of a novel bacterial communication system present in Vibrio cholerae. This system consists of a transcriptional regulator, VqmA and a small regulatory RNA (sRNA), VqmR.

VqmR is activated by VqmA and functions as a trans-acting regulator through base-pairing with multiple target mRNAs. Among these targets are key factors for biofilm formation and virulence factor expression in V.cholerae indicating that VqmA/R could participate in the regulation of complex behaviors. Indeed, our results show that VqmA binds to and is activated by an extracellular signal, which we determined as the novel autoinducer molecule, DPO. DPO is a new molecule to biology and is produced by diverse microbes. Further, we obtained evidence that the signaling molecule is produced by commensal species of the host microbiota and that VqmA/R plays an important role during V. cholerae pathogenesis and the communication with other bacteria.