The Bactofilin Cytoskeleton Protein BacM of Myxococcus xanthus Forms an Extended β-Sheet Structure Likely Mediated by Hydrophobic Interactions
| Autor: | Kefang Xie, Harald Engelhardt, Egbert Hoiczyk, David M. Zuckerman, Lauren E. Boucher, Jürgen Bosch |
|---|---|
| Přispěvatelé: | Kirby, JR |
| Jazyk: | angličtina |
| Rok vydání: | 2015 |
| Předmět: |
Models
Molecular Myxococcus xanthus Surface Properties Amino Acid Motifs Molecular Sequence Data Beta sheet lcsh:Medicine macromolecular substances Prokaryotic cytoskeleton 03 medical and health sciences Protein structure Bacterial Proteins Amino Acid Sequence lcsh:Science Cytoskeleton Protein secondary structure 030304 developmental biology 0303 health sciences Multidisciplinary biology lcsh:R 030302 biochemistry & molecular biology biology.organism_classification Cell biology Protein Structure Tertiary Chaotropic agent Cytoskeletal Proteins Polymerization lcsh:Q Protein Multimerization Hydrophobic and Hydrophilic Interactions Sequence Analysis Research Article |
| Zdroj: | PLoS ONE PLOS ONE PLoS ONE, Vol 10, Iss 3, p e0121074 (2015) |
| ISSN: | 1932-6203 |
| Popis: | Bactofilins are novel cytoskeleton proteins that are widespread in Gram-negative bacteria. Myxococcus xanthus, an important predatory soil bacterium, possesses four bactofilins of which one, BacM (Mxan_7475) plays an important role in cell shape maintenance. Electron and fluorescence light microscopy, as well as studies using over-expressed, purified BacM, indicate that this protein polymerizes in vivo and in vitro into similar to 3 nm wide filaments that further associate into higher ordered fibers of about 10 nm. Here we use a multipronged approach combining secondary structure determination, molecular modeling, biochemistry, and genetics to identify and characterize critical molecular elements that enable BacM to polymerize. Our results indicate that the bactofilin-determining domain DUF583 folds into an extended beta-sheet structure, and we hypothesize a left-handed beta-helix with polymerization into 3 nm filaments primarily via patches of hydrophobic amino acid residues. These patches form the interface allowing head-to-tail polymerization during filament formation. Biochemical analyses of these processes show that folding and polymerization occur across a wide variety of conditions and even in the presence of chaotropic agents such as one molar urea. Together, these data suggest that bactofilins are comprised of a structure unique to cytoskeleton proteins, which enables robust polymerization. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|