Fusion Tags Enhance The Solubility Of Expressed Proteins

The soluble of heterologous proteins remains a serious bottleneck in protein production. Although alteration of expression conditions can sometimes solve the problem, however, a systematic analysis of the utility of these solubility fusions has been difficult, and it appears that many proteins react differently to the presence of different solubility tags.

Today, there are a number of common solubility enhancing fusion tags that are used to express proteins. In some cases, these tags double as affinity tags, not only facilitating soluble expression but also increasing the efficiency of protein purification. In other cases, these solubility tags have been combined with a simple His-tag,allowing the fusion partner to maintain its solublizing functionality and also double as an affinity tag. Additional affinity tags that can be combined with many of these solubility-enhancing tags are also available and have been successfully used to produce purified proteins.

 

Some commonly used solubility-enhancing fusion partners

More details from: https://www.researchgate.net/publication/7002912

New fusion partners are constantly emerging and complementing the traditional solutions, as for instance, the Fh8 fusion tag that has been recently studied and ranked among the best solubility enhancer partners. A special emphasis is given to the recently discovered Fh8 fusion system that can be used for soluble protein production, purification, and immunogenicity in E. coli. The number of existing fusion tags will probably increase in the next few years, and efforts should be taken to better understand how fusion tags act in E. coli.

More details from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3928792/