[Streptavidin secretion by Streptomyces lividans strains]

Area of Science:

• Biotechnology
• Molecular Biology
• Microbial Engineering

Background:

• Streptavidin is a crucial protein with high affinity for biotin, widely used in molecular biology and diagnostics.
• Efficient and cost-effective production of streptavidin is essential for its broad application.
• Streptomyces lividans is a well-established host for protein secretion, but optimizing streptavidin yield requires further investigation.

Purpose of the Study:

• To engineer recombinant Streptomyces lividans strains for enhanced streptavidin secretion.
• To compare the productivity of different genetic constructs for streptavidin gene expression.
• To develop and describe novel vectors for Streptomyces expression systems.

Main Methods:

• Construction of recombinant S. lividans strains with streptavidin gene integrated into the chromosome.
• Construction of recombinant S. lividans strains with streptavidin gene cloned into a secretory vector.
• Evaluation and comparison of streptavidin productivity among different engineered strains.

Main Results:

• Isolated recombinant S. lividans strains capable of secreting streptavidin.
• Demonstrated that chromosomal integration of the streptavidin gene in S. lividans SA2 resulted in maximum productivity.
• Achieved streptavidin productivity of 60-80% relative to the native producer, S. avidinii.
• Described new vectors developed for use in Streptomyces.

Conclusions:

• Chromosomal integration of the streptavidin gene is an effective strategy for enhancing streptavidin production in S. lividans.
• The developed S. lividans SA2 strain represents a promising system for efficient streptavidin manufacturing.
• The novel Streptomyces vectors contribute to the toolkit for genetic manipulation and protein production in this genus.