| Autor: |
Jenni Leppiniemi, Toni Grönroos, Juha A E Määttä, Mark S Johnson, Markku S Kulomaa, Vesa P Hytönen, Tomi T Airenne |
| Jazyk: |
angličtina |
| Rok vydání: |
2012 |
| Předmět: |
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| Zdroj: |
PLoS ONE, Vol 7, Iss 5, p e35962 (2012) |
| Druh dokumentu: |
article |
| ISSN: |
1932-6203 |
| DOI: |
10.1371/journal.pone.0035962 |
| Popis: |
Bradavidin is a homotetrameric biotin-binding protein from Bradyrhizobium japonicum, a nitrogen fixing and root nodule-forming symbiotic bacterium of the soybean. Wild-type (wt) bradavidin has 138 amino acid residues, whereas the C-terminally truncated core-bradavidin has only 118 residues. We have solved the X-ray structure of wt bradavidin and found that the C-terminal amino acids of each subunit were uniquely bound to the biotin-binding pocket of an adjacent subunit. The biotin-binding pocket occupying peptide (SEKLSNTK) was named "Brad-tag" and it serves as an intrinsic stabilizing ligand in wt bradavidin. The binding of Brad-tag to core-bradavidin was analysed by isothermal titration calorimetry and a binding affinity of ∼25 µM was measured. In order to study the potential of Brad-tag, a green fluorescent protein tagged with Brad-tag was prepared and successfully concentrated from a bacterial cell lysate using core-bradavidin-functionalized Sepharose resin. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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