Partially folded forms of barley lipid transfer protein are more surface active.
Thermal and chemical modification of protein structures is known to affect their interfacial activity. We have looked in detail at the effect of heating on the structure and subsequently the surface properties of LTP1, a nonspecific lipid transfer protein from barley, both in the presence and in the absence of its lipid adduct. CD and NMR spectroscopy showed that some of the protein molecules refold back to the native state structure after being heated to 100 degrees C for 2 h. However, for a proportion of the molecules, the structure of the protein was irreversibly unfolded which resulted in an increase in surface activity irrespective of the presence of the lipid adduct. These molecules show an increase in surface activity, which is normally associated with an increase in molecular flexibility and surface hydrophobicity and is a property that has been shown to be highly sensitive to structural changes. This explains why thermal and chemical modification of LTP1 is important in optimizing the surface properties of the protein that are essential in diverse applications from biosensors to beer foam.
Clare Mills
E N
EN
Institute of Food Research, Norwich Research Park, Colney NR4 7UA, UK.
Gao
Chunli
C
Wilde
Peter J
PJ
Rigby
Neil M
NM
Wijesinha-Bettoni
Ramani
R
Johnson
Victoria E
VE
Smith
Lorna J
LJ
Mackie
Alan R
AR
D002352:Carrier Proteins / Q000737:chemistry* / Q000302:isolation & purification; D002942:Circular Dichroism; D001467:Hordeum / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D009682:Magnetic Resonance Spectroscopy; D010940:Plant Proteins / Q000737:chemistry* / Q000302:isolation & purification; D017510:Protein Folding; D055550:Protein Stability; D013499:Surface Properties
D002352:Carrier Proteins; D010940:Plant Proteins; C030363:lipid transfer protein