Structure of the Fundamental Lipopeptide Surfactin at the Air/Water Interface Investigated by Sum Frequency Generation Spectroscopy.
J Phys Chem B
; 121(19): 5072-5077, 2017 05 18.
Article
in En
| MEDLINE
| ID: mdl-28437109
ABSTRACT
The lipopeptide surfactin produced by certain strains of Bacillus subtilis is a powerful biosurfactant possessing potentially useful antimicrobial properties. In order to better understand its surface behavior, we have used surface sensitive sum frequency generation (SFG) vibrational spectroscopy in the C-H and CâO stretching regions to determine its structure at the air/water interface. Using surfactin with the leucine groups of the peptide ring perdeuterated, we have shown that a majority of the SFG signals arise from the 4 leucine residues. We find that surfactin forms a robust film, and that its structure is not affected by the number density at the interface or by pH variation of the subphase. The spectra show that the ring of the molecule lies in the plane of the surface rather than perpendicular to it, with the tail lying above this, also in the plane of the interface.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Surface-Active Agents
/
Water
/
Air
/
Lipopeptides
Language:
En
Journal:
J Phys Chem B
Journal subject:
QUIMICA
Year:
2017
Document type:
Article
Affiliation country:
United kingdom
Country of publication:
EEUU
/
ESTADOS UNIDOS
/
ESTADOS UNIDOS DA AMERICA
/
EUA
/
UNITED STATES
/
UNITED STATES OF AMERICA
/
US
/
USA