skip to main content

DOE PAGESDOE PAGES

Title: Ice-nucleating bacteria control the order and dynamics of interfacial water

Ice-nucleating organisms play important roles in the environment. With their ability to induce ice formation at temperatures just below the ice melting point, bacteria such as Pseudomonas syringae attack plants through frost damage using specialized ice-nucleating proteins. Besides the impact on agriculture and microbial ecology, airborne P. syringae can affect atmospheric glaciation processes, with consequences for cloud evolution, precipitation, and climate. Biogenic ice nucleation is also relevant for artificial snow production and for biomimetic materials for controlled interfacial freezing. We use interface-specific sum frequency generation (SFG) spectroscopy to show that hydrogen bonding at the water-bacteria contact imposes structural ordering on the adjacent water network. Experimental SFG data and molecular dynamics simulations demonstrate that ice active sites within P. syringae feature unique hydrophilic-hydrophobic patterns to enhance ice nucleation. Finally, the freezing transition is further facilitated by the highly effective removal of latent heat from the nucleation site, as apparent from time-resolved SFG spectroscopy.
Authors:
 [1] ;  [2] ;  [3] ;  [4] ;  [4] ;  [2] ;  [2] ;  [5] ;  [2] ;  [2] ;  [5] ;  [6] ;  [5] ;  [2] ;  [7]
  1. Max Planck Institute for Polymer Research, Mainz (Germany); Univ. of Texas, Austin, TX (United States)
  2. Max Planck Institute for Polymer Research, Mainz (Germany)
  3. Max Planck Institute for Polymer Research, Mainz (Germany); Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
  4. Univ. of Washington, Seattle, WA (United States)
  5. Max Planck Institute for Chemistry, Mainz (Germany)
  6. Stony Brook Univ., Stony Brook, NY (United States)
  7. Max Planck Institute for Polymer Research, Mainz (Germany); Univ. of Washington, Seattle, WA (United States)
Publication Date:
Grant/Contract Number:
SC0008613
Type:
Accepted Manuscript
Journal Name:
Science Advances
Additional Journal Information:
Journal Volume: 2; Journal Issue: 4; Journal ID: ISSN 2375-2548
Publisher:
AAAS
Research Org:
Stony Brook Univ., Stony Brook, NY (United States)
Sponsoring Org:
USDOE Office of Science (SC), Biological and Environmental Research (BER) (SC-23)
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; ice nucleation; Pseudomonas Syringae; ice protein; sum frequency generation
OSTI Identifier:
1349437