CdbA is a DNA-binding protein and c-di-GMP receptor important for nucleoid organization and segregation in Myxococcus xanthus

Research output: Contribution to journalArticlepeer-review

Authors

  • Dorota Skotnicka
  • Wieland Steinchen
  • Dobromir Szadkowski
  • Gert Bange
  • Lotte Søgaard-andersen

Colleges, School and Institutes

Abstract

Cyclic di-GMP (c-di-GMP) is a second messenger that modulates multiple responses to environmental and cellular signals in bacteria. Here we identify CdbA, a DNA-binding protein of the ribbon-helix-helix family that binds c-di-GMP in Myxococcus xanthus. CdbA is essential for viability, and its depletion causes defects in chromosome organization and segregation leading to a block in cell division. The protein binds to the M. xanthus genome at multiple sites, with moderate sequence specificity; however, its depletion causes only modest changes in transcription. The interactions of CdbA with c-di-GMP and DNA appear to be mutually exclusive and residue substitutions in CdbA regions important for c-di-GMP binding abolish binding to both c-di-GMP and DNA, rendering these protein variants non-functional in vivo. We propose that CdbA acts as a nucleoid-associated protein that contributes to chromosome organization and is modulated by c-di-GMP, thus revealing a link between c-di-GMP signaling and chromosome biology.

Bibliographic note

Funding Information: We thank Jörg Kahnt for mass-spectrometry analysis, Dr. Nuria Gómez Santos for providing the plasmid pNG62, Prof. Dr. Anke Becker for helpful discussions and Max Planck Genome Centre Cologne (https://mpgc.mpipz.mpg.de/home) for ChIP-seq library construction and next-generation sequencing. This work was supported by funding from the Deutsche Forschungsgemeinschaft (DFG) within the framework of the Collaborative Research Center SFB987 “Microbial Diversity in Environmental Signal Response” (to L.S.-A.) and the priority programme SPP 1879 “Nucleotide Second Messenger Signaling in Bacteria” (to L.S.-A. and G.B.) and the Max Planck Society (to L.S.-A.). We acknowledge support by the Deutsche Forschungsgemeinschaft (DFG) through the DFG core facility for interactions, dynamics, and macromolecular assembly structure (to G.B.).

Details

Original languageEnglish
Article number1791
Number of pages19
JournalNature Communications
Volume11
Issue number1
Publication statusPublished - 14 Apr 2020

Keywords

  • Bacterial Proteins/chemistry, Base Sequence, Cell Nucleus/metabolism, Chromosome Segregation, Chromosomes, Bacterial/metabolism, Cyclic GMP/analogs & derivatives, DNA, Bacterial/metabolism, DNA-Binding Proteins/metabolism, Genetic Loci, Models, Molecular, Myxococcus xanthus/metabolism, Protein Multimerization, Protein Structure, Secondary, Transcription, Genetic