Abstract
This essay shows how Fourier transform infrared (FTIR) microspectroscopy can be applied to study thermodynamic parameters and conformation of endogenous biomolecules in desiccation-tolerant biological tissues. Desiccation tolerance is the remarkable ability of some organisms to survive complete dehydration. Seed and pollen of higher plants are well known examples of desiccation-tolerant tissues. FTIR studies on the overall protein secondary structure indicate that during the acquisition of desiccation tolerance, plant embryos exhibit proportional increases in alpha-helical structures and that beta-sheet structures dominate upon drying of desiccation sensitive-embryos. During ageing of pollen and seeds, the overall protein secondary structure remains stable, whereas drastic changes in the thermotropic response of membranes occur, which coincide with a complete loss of viability. Properties of the cytoplasmic glassy matrix in desiccation-tolerant plant organs can be studied by monitoring the position of the OH-stretching vibration band of endogenous carbohydrates and proteins as a function of temperature. By applying these FTIR techniques to maturation-defective mutant seeds of Arabidopsis thaliana we were able to establish a correlation between macromolecular stability and desiccation tolerance. Taken together, in situ FTIR studies can give unique information on conformation and stability of endogenous biomolecules in desiccation-tolerant tissues.
Original language | English |
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Pages (from-to) | 297-313 |
Journal | Spectroscopy: an international journal |
Volume | 17 |
DOIs | |
Publication status | Published - 2003 |
Keywords
- transform infrared-spectroscopy
- protein secondary structure
- electron-paramagnetic-resonance
- typha-latifolia l
- plant craterostigma-plantagineum
- carrot somatic embryos
- abscisic-acid
- arabidopsis-thaliana
- phase-transitions
- seed development