Effective extracellular trehalose production by Cellulosimicrobium cellulans

Area of Science:

• Microbiology
• Biochemistry
• Industrial Biotechnology

Background:

• Trehalose is a disaccharide with significant industrial applications.
• Bacterial production of extracellular trehalose is an area of interest for sustainable manufacturing.

Purpose of the Study:

• To identify and characterize a bacterial strain capable of producing extracellular trehalose.
• To optimize conditions for maximizing trehalose yield from bacterial fermentation.

Main Methods:

• Isolation and identification of bacterial strain ST26 using 16S rDNA sequencing.
• Phylogenetic analysis placing ST26 within the Cellulosimicrobium/Cellulomonas genus.
• Optimization of culture media components (glucose, ammonium sulfate, CaCO3) and pH for trehalose production.

Main Results:

• Strain ST26, identified as related to Cellulosimicrobium cellulans, efficiently produces extracellular trehalose from glucose.
• Trehalose production was specific to glucose and not observed with sucrose, glycerol, or maltose.
• Optimized conditions (0.5-1% ammonium sulfate, 0.5-1% CaCO3, pH ~5.0) yielded a 61% conversion rate of glucose to trehalose.
• Ammonium sulfate addition reduced cell mass and intracellular trehalose, suggesting enhanced extracellular leakage.

Conclusions:

• The Cellulomonas genus commonly produces extracellular trehalose.
• Optimized fermentation conditions enable high-yield bacterial trehalose production.
• Trehalose serves as a carbon reserve for the bacterium, which can utilize it as a sole carbon source.