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Looking Outwards: Isolation of Cyanobacterial Released Carbohydrate Polymers and Proteins
Published on: May 27, 2019
[Permeability of cyanobacterial mucous surface structures for macromolecules]
Mikrobiologiia
|June 5, 2008
Summary
Researchers studied how dextrans, or sugar polymers, move within the mucous surface structures (MSS) of cyanobacteria. This research reveals how these structures act as barriers, influencing interactions between microorganisms.
Area of Science:
- Microbiology
- Biophysics
- Biochemistry
Background:
- The mucous surface structures (MSS) of cyanobacteria are diverse in morphology and ultrastructure across different species and strains.
- These cyanobacteria can form associations with plants and animals, often growing as mucous microcolonies.
- The role of MSS as permeability barriers in microbial interactions is not fully understood.
Purpose of the Study:
- To investigate the diffusive distribution of neutral hydrophilic macromolecules (dextrans) within the MSS of intact cyanobacteria.
- To determine the permeability range of cyanobacterial MSS for molecules of varying sizes.
- To compare the macromolecular organization of cyanobacterial MSS with plant cell wall components.
Main Methods:
- Studied the diffusive distribution of dextrans (1.5 to 9 nm Stokes radius) in cyanobacterial MSS.
- Employed the dextran fractionation method, previously used for plants, combined with electron microscopy.
- Analyzed various cyanobacterial species and strains with differing MSS morphology.
Main Results:
- Established the range of permeability for cyanobacterial MSS based on dextran size.
- Observed that dextrans distribute within the MSS polysaccharide matrix according to their molecular size, similar to a macroporous gel.
- Identified similarities in chemical composition and macromolecular organization between cyanobacterial MSS and plant pectins.
Conclusions:
- Cyanobacterial MSS act as size-selective permeability barriers, influencing molecular diffusion.
- The macromolecular organization of MSS is comparable to plant cell wall pectins.
- MSS play a role as permeability barriers in the associative interactions of microorganisms.
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