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Glycan Profiling of Plant Cell Wall Polymers using Microarrays
Published on: December 17, 2012
Plant Cell Wall Carbohydrates as Substrates for Azospirillum brasiliense
1Department of Soil Science, University of Florida, Gainesville, Florida 32611.
Applied and Environmental Microbiology
|December 1, 1987
Summary
Pearl millet (Pennisetum americanum) cell wall simple sugars support Azospirillum brasiliense growth. However, polysaccharides from pearl millet cell walls do not appear to be usable substrates for this root-associated diazotroph.
Area of Science:
- Plant biochemistry
- Microbial metabolism
- Nitrogen fixation
Background:
- Root-associated diazotrophs, like Azospirillum brasiliense, play a crucial role in plant growth and nitrogen cycling.
- Understanding the carbon sources available to these microbes in the rhizosphere is key to optimizing their beneficial effects.
- Pearl millet (Pennisetum americanum) is a vital cereal crop, and its root exudates and cell wall components are potential nutrient sources.
Purpose of the Study:
- To investigate the utilization of pearl millet (Pennisetum americanum) cell wall carbohydrate components by the root-associated diazotroph Azospirillum brasiliense Sp. 7.
- To determine if simple sugars and polysaccharides from pearl millet cell walls can serve as substrates for A. brasiliense growth.
Main Methods:
- Analysis of carbohydrate composition in pearl millet (Pennisetum americanum) cell walls.
- Culturing of Azospirillum brasiliense Sp. 7 with different carbohydrate fractions (simple sugars and polysaccharides).
- Monitoring bacterial growth and assessing substrate utilization.
Main Results:
- Azospirillum brasiliense Sp. 7 effectively utilized simple sugars present in pearl millet (Pennisetum americanum) cell walls.
- No evidence was found to support the growth of A. brasiliense on the polysaccharide components of pearl millet cell walls, even after potential hydrolysis.
Conclusions:
- Simple sugars from pearl millet (Pennisetum americanum) cell walls are readily available and support the growth of Azospirillum brasiliense.
- Polysaccharides from pearl millet cell walls are not readily utilized by Azospirillum brasiliense Sp. 7, suggesting limited contribution to its nutrition in the rhizosphere.
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