6BG8

Shewanella frigidimarina ice-binding protein_1 DUF3494 Domain

Summary for 6BG8

• Entry DOI: 10.2210/pdb6bg8/pdb
• Descriptor: Ig domain protein, group 2 domain protein, SULFATE ION, GLYCEROL, ... (6 entities in total)
• Functional Keywords: ice adhesin, duf3494 domain, c-terminal domain, antifreeze protein
• Biological source: Shewanella frigidimarina (strain NCIMB 400)
• Total number of polymer chains: 2
• Total formula weight: 52532.47

Authors

Vance, T.D.R.,Davies, P.L. (deposition date: 2017-10-27, release date: 2018-03-07, Last modification date: 2024-04-03)

Primary citation

Vance, T.D.R.,Graham, L.A.,Davies, P.L.
An ice-binding and tandem beta-sandwich domain-containing protein in Shewanella frigidimarina is a potential new type of ice adhesin.
FEBS J., 285:1511-1527, 2018

PubMed Abstract: Out of the dozen different ice-binding protein (IBP) structures known, the DUF3494 domain is the most widespread, having been passed many times between prokaryotic and eukaryotic microorganisms by horizontal gene transfer. This ~25-kDa β-solenoid domain with an adjacent parallel α-helix is most commonly associated with an N-terminal secretory signal peptide. However, examples of the DUF3494 domain preceded by tandem Bacterial Immunoglobulin-like (BIg) domains are sometimes found, though uncharacterized. Here, we present one such protein (SfIBP_1) from the Antarctic bacterium Shewanella frigidimarina. We have confirmed and characterized the ice-binding activity of its ice-binding domain using thermal hysteresis measurements, fluorescent ice plane affinity analysis, and ice recrystallization inhibition assays. X-ray crystallography was used to solve the structure of the SfIBP_1 ice-binding domain, to further characterize its ice-binding surface and unique method of stabilizing or 'capping' the ends of the solenoid structure. The latter is formed from the interaction of two loops mediated by a combination of tandem prolines and electrostatic interactions. Furthermore, given their domain architecture and membrane association, we propose that these BIg-containing DUF3494 IBPs serve as ice-binding adhesion proteins that are capable of adsorbing their host bacterium onto ice.

PubMed: 29498209
DOI: 10.1111/febs.14424

Experimental method

X-RAY DIFFRACTION (1.59712947109 Å)