Secretion of streptavidin from Bacillus subtilis

Area of Science:

• Biochemistry
• Molecular Biology
• Microbial Biotechnology

Background:

• Streptavidin is a tetrameric protein with high affinity for biotin, crucial in molecular biology applications.
• Streptomyces avidinii is the native producer of streptavidin, but alternative expression systems are sought for improved production.
• Efficient production of streptavidin is essential for various diagnostic and research tools.

Purpose of the Study:

• To engineer Bacillus subtilis as a host for streptavidin production.
• To evaluate the properties of streptavidin produced in B. subtilis.
• To establish an alternative and potentially more efficient system for streptavidin generation.

Main Methods:

• Construction of hybrid genes fusing Bacillus signal peptides to the streptavidin sequence.
• Transformation of B. subtilis with engineered plasmids.
• Cultivation of B. subtilis strains in biotin-free media.
• Characterization of the produced streptavidin.

Main Results:

• B. subtilis strains successfully produced and secreted tetrameric streptavidin into the growth medium.
• The properties of streptavidin produced by B. subtilis were comparable to those from S. avidinii.
• High cell density cultivation of B. subtilis was achieved in biotin-free conditions.

Conclusions:

• Bacillus subtilis serves as a viable alternative host for streptavidin production.
• This engineered system offers a promising platform for scalable streptavidin manufacturing.
• The B. subtilis system facilitates the production of functional streptavidin for diverse applications.