Bacterial Expression System for Vaccine Production
Classic methods to produce antigens for vaccine development include isolating the inactivated or attenuated pathogens. The approaches were historically successful, but there still exist several flaws: (i) insufficient inactivation or attenuation of the pathogen may still be harmful for individuals especially for immunosuppressed ones; (ii) the present manner of antigen may be changed after inactivation; (iii) the sophisticated production procedures and facilities; (iv) the impurities of the antigen may cause unexpected adverse reactions. The concept of recombinant subunit vaccine could avoid these limitations which involves the process of cloning of a targeted gene and its expression. Creative Biolabs has rich experiences in protein production with diverse expression systems and is fully committed to provide the tailor-made services to meet all your demands.
Fig.1 Classical approach for antigens production (A) and much advanced approach (B). (Manmohan and Indresh, 2011)
Increasing large scale applications of vaccines drive the problems of rapid production and vast amounts of protein. Furthermore, some proteins also need extra post-translational modifications to guarantee their normal functions. Besides, the time to produce target protein, the expected yield, the ease of operation and the form researchers prefer the protein to present should be considered. All these requests led to the exploiting of different protein expression systems. Such expression systems include prokaryotic protein expression systems like bacterial expression systems and eukaryotic expression systems like yeast expression system, insect expression system, mammalian cell expression system, plant expression system and so on.
Bacterial Expression System
Bacteria have advantages of rapid growth speed, simple structure, easy manipulations and low costs, thus have been widely used. Till now, scientists have developed kinds of bacterial expression systems to cover the multifaceted demands in protein production.
E. coli Expression System
E. coli expression system is the main choice in the bacterial expression systems and is generally applied in laboratory research and commercial activities. The method to produce proteins in E. coli is well-established also with high yields. The products made this way are often used for structure analysis, function analysis and analysis of interactions among proteins, however, the proteins are usually presented in a form of inclusion body which made the subsequent process much complex and time-consuming.
Our Strategies to Enhance the Solubility of the Target Protein:
- Modifying the original secretion system genetically
- Using carrier proteins
- Co-expression with other soluble proteins
- Using proper signal peptides
- Optimizing culture conditions
- Choosing appropriate expression vector
Lactoccocus lactis Expression System
Lactoccocus lactis is a Gram-positive bacterial expression system and is playing an increasingly important role in protein production. It gets the upper hand in being GRAS and free of endotoxin, which makes it a safer tool to manufacture proteins for therapeutic or edible. What’s more, Lactoccocus lactis is superior to E. coli in possessing only one membrane and low possibility to produce inclusion body, making the process of purification less laborious.
Pseudomonas Expression System
Pseudomonas, a Gram-negative bacterium, abundant in soil and water, has advantages in fast growth and hyper yield of producing recombinant proteins. In addition, some of the species are capable of synthesizing alginate, a component widely used in food and medicines. Commonly used Pseudomonas species include P. fluorescens, P. aeruginosa, and P. putida, all of which are independent on oxygen concentration and hardly generate acetate into cultures, thus simplifying the fermentation conditions.
Other Bacterial Expression System
Other than expression systems mentioned above, some alternative new bacterial expression systems are appealing to investigators owing to their traits to satisfy the particular study needs, including Streptomyces systems with ability to secret soluble proteins, coryneform bacteria systems and halophilic bacteria systems. Each protein expression system has its own unique advantages; thus a reasonable protocol design, the selection of the appropriate expression system, and proper post-processing are critical to obtaining the desired protein.
Features of Our Bacterial Expression System
- Fast and efficient gene synthesis and codon optimization services
- Various and well-established bacterial expression systems
- Multiple expression vectors to meet different research needs
- High-throughput protein production platform
- Diversified strategies for protein post-translational modifications
- Mature technologies in protein purification and renaturation
As a specialist in protein expression with multiple expression systems especially bacterial expression system, Creative Biolabs will spare no effort to provide customized services that meet all requirements to our clients.
Reference
- Rachel, C. (2012). “Bacterial expression systems for recombinant protein production: E. coli and beyond.” Biotechnol Adv. 30(5): 1102-7.
All of our products can only be used for research purposes. These vaccine ingredients CANNOT be used directly on humans or animals.
