Send to

Choose Destination
Microbiologyopen. 2017 Feb;6(1). doi: 10.1002/mbo3.414. Epub 2016 Oct 22.

Expanding the archaellum regulatory network - the eukaryotic protein kinases ArnC and ArnD influence motility of Sulfolobus acidocaldarius.

Author information

Molecular Biology of Archaea, Institute of Biology II, Faculty of Biology, Microbiology, University of Freiburg, Freiburg, Germany.
Department of Biochemistry and Functional Proteomics, Institute of Biology II, Faculty of Biology, University of Freiburg, Freiburg, Germany.
Department of Life Sciences, Imperial College of London, London, UK.
BIOSS Centre for Biological Signaling Studies, University of Freiburg, Freiburg, Germany.


Expression of the archaellum, the archaeal-type IV pilus-like rotating motility structure is upregulated under nutrient limitation. This is controlled by a network of regulators, called the archaellum regulatory network (arn). Several of the components of this network in Sulfolobus acidocaldarius can be phosphorylated, and the deletion of the phosphatase PP2A results in strongly increased motility during starvation, indicating a role for phosphorylation in the regulation of motility. Analysis of the motility of different protein kinase deletion strains revealed that deletion of saci_0965, saci_1181, and saci_1193 resulted in reduced motility, whereas the deletion of saci_1694 resulted in hypermotility. Here ArnC (Saci_1193) and ArnD (Saci_1694) are characterized. Purified ArnC and ArnD phosphorylate serine and threonine residues in the C-terminus of the repressor ArnB. arnC is upregulated in starvation medium, whereas arnD is constitutively expressed. However, while differences in the expression and levels of flaB were observed in the ΔarnD strain during growth under rich conditions, under nutrient limiting conditions the ΔarnC and ΔarnD strains showed no large differences in the expression levels of the archaellum or of the studied regulators. This suggests that next to the regulation via the archaellum regulatory network additional regulatory mechanisms of expression and/or activity of the archaellum exist.


S. acidocaldarius ; archaeal flagella; archaellum regulation; phosphorylation; protein kinases; signaling network

[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Wiley Icon for PubMed Central
Loading ...
Support Center