| Full text | |
| Author(s): |
Gonzalez-Hourcade, Maria
[1]
;
del Campo, Eva M.
[1]
;
Braga, Marcia R.
[2]
;
Salgado, Antonio
[3]
;
Casano, Leonardo M.
[1]
Total Authors: 5
|
| Affiliation: | [1] Univ Alcala De Henares, Dept Life Sci, Madrid 28871 - Spain
[2] Inst Bot, Dept Plant Physiol & Biochem, BR-04301012 Sao Paulo, SP - Brazil
[3] Univ Alcala De Henares, Fac Pharm, Ctr Espectroscopia RMN CERMN, Madrid 28805 - Spain
Total Affiliations: 3
|
| Document type: | Journal article |
| Source: | ENVIRONMENTAL MICROBIOLOGY; v. 22, n. 8 MAY 2020. |
| Web of Science Citations: | 0 |
| Abstract | |
Trebouxia sp. TR9 and Coccomyxa simplex are desiccation-tolerant microalgae with flexible cell walls, which undergo species-specific remodelling during dehydration-rehydration (D/R) due to their distinct ultrastructure and biochemical composition. Here, we tested the hypothesis that extracellular polysaccharides excreted by each microalga could be quantitatively and/or qualitatively modified by D/R. Extracellular polysaccharides were analysed by size exclusion and anion exchange chromatography, specific stains after gel electrophoresis and gas chromatography/mass spectrometry of trimethylsilyl derivatives (to determine their monosaccharide composition). The structure of a TR9-sulfated polymer was deduced from nuclear magnetic resonance (NMR) analyses. In addition, sugar-sulfotransferase encoding genes were identified in both microalgae, and their expression was measured by RT-qPCR. D/R did not alter the polydispersed profile of extracellular polysaccharides in either microalga but did induce quantitative changes in several peaks. Furthermore, medium-low-sized uronic acid-containing polysaccharides were almost completely substituted by higher molecular mass carbohydrates after D/R. Sulfated polysaccharide(s) were detected, for the first time, in the extracellular polymeric substances of both microalgae, but only increased significantly in TR9 after cyclic D/R, which induced a sugar-sulfotransferase gene and accumulated sulfated ss-D-galactofuranan(s). Biochemical remodelling of extracellular polysaccharides in aeroterrestrial desiccation-tolerant microalgae is species-specific and seems to play a role in the response to changes in environmental water availability. (AU) | |
| FAPESP's process: | 17/50341-0 - Challenges for biodiversity conservation facing climate changes, pollution, land use and occupation (PDIp) |
| Grantee: | Luiz Mauro Barbosa |
| Support Opportunities: | Research Grants - State Research Institutes Modernization Program |