A single step purification process for cyclodextrin glucanotransferase from a Bacillus sp. isolated from soil

Area of Science:

• Biochemistry
• Enzymology
• Microbiology

Background:

• Cyclodextrin glucanotransferase (CGTase) is crucial for cyclodextrin production from starch.
• Optimizing CGTase production and purification is vital for industrial applications.

Purpose of the Study:

• To isolate and characterize a novel CGTase-producing bacterium.
• To optimize enzyme production and develop an efficient purification method.
• To investigate the biochemical properties and stability of the purified CGTase.

Main Methods:

• Isolation of CGTase-producing bacteria from soil samples.
• Media optimization to enhance enzyme yield.
• Single affinity precipitation for enzyme purification.
• SDS-PAGE for molecular weight determination.
• Enzyme activity assays under varying pH, temperature, and chemical conditions.

Main Results:

• A high-activity CGTase-producing bacterium was isolated, with enzyme activity increased from 7.5 to 22 U/mL through media design.
• A novel single affinity precipitation step achieved over 90% recovery of a homogeneous 68 kDa enzyme.
• The enzyme exhibited optimal activity at pH 6.6 and 65°C, with high stability at 65°C for 8 hours.
• 10 mM urea significantly increased enzyme activity by over 200%, indicating unique properties.

Conclusions:

• The study successfully isolated and characterized a potent CGTase with enhanced production and a highly efficient purification protocol.
• The enzyme's unique stability and significant activation by urea present promising avenues for industrial biotechnology.
• Further research into the enzyme's structure and mechanism could unlock novel applications in starch processing and beyond.