Estimation of Polymer Rigidity in Cell Walls of Growing and Nongrowing Celery Collenchyma by Solid-State Nuclear Magnetic Resonance in Vivo.

AUTOR(ES)

Fenwick, K. M.

RESUMO

When the growth of a plant cell ceases, its walls become more rigid and lose the capacity to extend. Nuclear magnetic resonance relaxation methods were used to determine the molecular mobility of cell wall polymers in growing and nongrowing live celery (Apium graveolens L.) collenchyma. To our knowledge, this is the first time this approach has been used in vivo. Decreased polymer mobility in nongrowing cell walls was detected through the 13C-nuclear magnetic resonance spectrum by decreases in the proton spin-spin relaxation time constant and in the intensity of a sub-spectrum corresponding to highly mobile pectins, which was obtained by a spectral editing technique based on cross-polarization rates. Flexible, highly methyl-esterified pectins decreased in relative quantity when growth ceased. A parallel increase in the net longitudinal orientation of cellulose microfibrils was detected in isolated cell walls by polarized Fourier-transformed infrared spectrometry.

Documentos Relacionados

• Solid-State 13C Nuclear Magnetic Resonance Characterization of Cellulose in the Cell Walls of Arabidopsis thaliana Leaves.
• Following Suberization in Potato Wound Periderm by Histochemical and Solid-State 13C Nuclear Magnetic Resonance Methods.
• Biodegradation of lignocellulose in Bermuda grass by white rot fungi analyzed by solid-state 13C nuclear magnetic resonance.
• Solid-state 13C nuclear magnetic resonance spectroscopy of simultaneously metabolized acetate and phenol in a soil Pseudomonas sp.
• High-resolution solid-state 13C nuclear magnetic resonance of bacterial spores: identification of the alpha-carbon signal of dipicolinic acid.