Document Type
Article
Publication Title
mBio
Department
Biological Sciences
ISSN
21507511
Volume
13
Issue
3
DOI
10.1128/mbio.00514-22
First Page
1
Last Page
11
Publication Date
4-14-2022
Abstract
Surface motility powered by type IV pili (T4P) is widespread among bacteria, including the photosynthetic cyanobacteria. This form of movement typically requires the deposition of a motility-associated polysaccharide, and several studies indicate that there is complex coregulation of T4P motor activity and polysaccharide production, although a mechanistic understanding of this coregulation is not fully defined. Here, using a combination of genetic, comparative genomic, transcriptomic, protein-protein interaction, and cytological approaches in the model filamentous cyanobacterium N. punctiforme, we provided evidence that a DnaK-type chaperone system coupled the activity of the T4P motors to the production of the motility-associated hormogonium polysaccharide (HPS). The results from these studies indicated that DnaK1 and DnaJ3 along with GrpE comprised a chaperone system that interacted specifically with active T4P motors and was required to produce HPS. Genomic conservation in cyanobacteria and the conservation of the protein-protein interaction network in the model unicellular cyanobacterium Synechocystis sp. strain PCC 6803 imply that this system is conserved among nearly all motile cyanobacteria and provides a mechanism to coordinate polysaccharide secretion and T4P activity in these organisms.
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This work is licensed under a Creative Commons Attribution 4.0 International License.
Recommended Citation
McDonald, Heather J.; Kweon, HoJun; Kurnfuli, Shadi; and Risser, Douglas D., "A DnaK(Hsp70) Chaperone System Connects Type IV Pilus Activity to Polysaccharide Secretion in Cyanobacteria" (2022). Pacific Faculty Work. 189.
https://scholarlycommons.pacific.edu/all-faculty/189