Novel strategy for expression of authentic and bioactive human basic fibroblast growth factor in Bacillus subtilis

• Published in: Applied microbiology and biotechnology 2018-08, Vol.102 (16), p.7061-7069
• Main Authors: Hu, Xiuhua, Lai, Cheuk Yin Nelson, Sivakumar, T., Wang, Hao, Ng, K. L., Lam, C. C., Wong, W. K. R.
• Format: Article
• Language: English
• Subjects: Applied Genetics and Molecular Biotechnology; Bacillus subtilis; Bacillus subtilis - genetics; Bacillus subtilis - metabolism; Biological activity; Biomedical and Life Sciences; Biotechnology; Catalysis; Cellulose; E coli; Endoglucanase; Fibroblast growth factor 2; Fibroblast Growth Factor 2 - genetics; Fibroblast growth factors; Fibroblasts; Growth factors; Humans; Industrial Microbiology - methods; Inteins; Introns; Life Sciences; Microbial Genetics and Genomics; Microbiology; Microorganisms; N-Terminus; Physiological aspects; Production processes; Protein purification; Protein Splicing; Proteins; Recombinant Proteins - genetics
• ISSN: 0175-7598; 1432-0614
• DOI: 10.1007/s00253-018-9176-1

Inteins, also known as “protein introns,” have been found to be present in many microbial species and widely employed for the expression and purification of recombinant proteins in Escherichia coli . However, interestingly, until now there has not been much information on the identification and application of inteins to protein expression in Bacillus subtilis . In this article, for the first time, despite the likelihood of absence of inteins in B. subtilis , this bacterium was shown to be able to facilitate auto-catalytic cleavages of fusions formed between inteins and recombinant proteins. Employing a construct expressing the intein, Ssp DnaB, (DnaB), which was fused at its N-terminus with the cellulose-binding domain (CellBD) of an endoglucanase encoded by the cenA gene of Cellulomonas fimi , the construct was demonstrated to be capable of mediating intracellular expression of basic fibroblast growth factor (bFGF), followed by auto-processing of the CellBD-DnaB-bFGF fusion to result in bFGF possessing the 146-residue authentic structure. The mentioned fusion was shown to result in a high yield of 84 mg l −1 of biologically active bFGF. Future work in improving the growth of B. subtilis may enable the use of this bacterium, working in cooperation with inteins, to result in a new platform for efficient expression of valuable proteins.