Developing a codon optimization method for improved expression of recombinant proteins in actinobacteria.

Area of Science:

• Biotechnology
• Molecular Biology
• Microbial Engineering

Background:

• Codon optimization via synonymous substitution is crucial for recombinant protein production.
• Previous optimization studies primarily focused on Escherichia coli, limiting applications in other hosts.
• Rhodococcus erythropolis, a GC-rich actinobacterium, is an emerging host for biotechnology.

Purpose of the Study:

• To develop and validate a novel codon optimization strategy for Rhodococcus erythropolis.
• To identify key sequence features influencing gene expression in R. erythropolis.
• To improve recombinant protein yields in this alternative bacterial host.

Main Methods:

• Evaluated recombinant protein expression for 204 genes in R. erythropolis using a consistent plasmid vector.
• Performed statistical analysis to identify significant sequence features for codon optimization.
• Applied identified features to optimize coding sequences of 12 target genes.

Main Results:

• Identified 5' mRNA folding energy and codon frequency as critical factors for R. erythropolis codon optimization.
• Observed distinct sequence feature tendencies compared to previous studies in Escherichia coli.
• Achieved increased expression in 75% (9 out of 12) of optimized genes, with significant improvements for previously low-expressing genes.

Conclusions:

• The developed codon optimization method is effective for R. erythropolis.
• The findings provide insights into sequence-based gene expression regulation in actinobacteria.
• This approach holds potential for enhancing protein expression in other actinobacterial hosts.