Agriculture Reference
In-Depth Information
directly interact with the protein surface, they alter protein surface properties by changing
the water structure and hydrophobic interactions, thereby stabilizing the folded states rela‐
tive to unfolded states. Even under native conditions, osmolytes were shown to favor the
compact folded structure over partially folded structures, consequently leading to altera‐
tions in the dynamics of these two states. Thermodynamic considerations assume that osmo‐
lytes act by raising the chemical potential of the partially unfolded state relative to the
folded state, thereby increasing the (positive) Gibbs energy difference (ΔG) between folded
and unfolded assemblies, thus favoring the folded state with the respect to the unfolded
state. By stabilizing compact folded states over unfolded structures even under non-stress
conditions, osmolyte accumulation exhibits a great potential to counteract the forces that
lead to stress induced protein unfolding. High osmolyte accumulation in plants may not be
useful under non-stress conditions as they tend to decrease protein globally and locally flex‐
ibility and increase protein overall rigidity. Increased rigidity and overall compactness,
however, confer great advances under stress conditions. Compact structures are less prone
to unfolding, misfolding, aggregation and degradation. Lower structural flexibility under
ambient temperatures allows for greater flexibility under elevated temperatures since ther‐
mal motion decreases rigidity and enhances flexibility, which is essential for protein func‐
tion under stress conditions. Osmolyte production seems to be very effective strategy to
adopt plants quickly and with a remarkable plasticity to various changes in their environ‐
ment. High osmolyte accumulation serves to suppress protein unfolding and misfolding, en‐
hances protein folding stability and facilitate the protein refolding process after complete
denaturation. These lessions that we learned from plants and new insights from the protein
biochemistry field are taken together for genetically engineering of more tolerant crop
plants with the ultimate goal to improve yields in less productive agricultural land.
Acknowledgements
This work was done in collaboration between the Department of Chemical Physiology of
Plants and the Department of Biomolecular Structural Chemistry at the University of Vien‐
na. The author would like to thank Marianne Popp, Robert Konrat, Martin Tollinger and
Karin Kloiber for supporting this research and the latter three for providing their expertise
in Nuclear Magnetic Resonance Spectroscopy. The author is also grateful to Jürgen König
for supporting this work.
Author details
Martina Ortbauer
Address all correspondence to: martina.ortbauer@univie.ac.at
University of Vienna, Vienna, Austria
Search WWH ::




Custom Search