Exploring diverse signal peptides with secretion of shark VNAR antibody from corynebacterium glutamicum using FAST dye assay

Abstract

Engineering of bacterial strains with efficient antibody secretion is important in terms of economical benefits compared to that of eukaryotic cells. However, the work of strain design for fine antibody secretion has been constrained for further development by several reasons such as structural stability of antibody and safety issue of host cell. Especially, even though Corynebacaterium glutamicum has remarkable characteristics that it is a GRAS (Generally Regarded as Safe) strain that has its thick membrane system to maintain intracellular condition, there is a lack of study on the strain with antibody secretion. Thus, for further development of study in antibody secretion from bacterial strain, this study was based on C. glutamicum, and in purpose of excluding the problem on structural stability of antibody, nanobody antibody called shark VNAR antibody was used to investigate the potential of C. glutmaicum as a host cell for antibody secretion. For contributing a condition of selecting diverse signal peptides to this study, an artificial signal peptide library was constructed upstream of gene encoding a humanized shark VNAR antibody called HuVAR version I. FAST (Flourescene-activating and Absorption-Shifting Tag) dye assay was employed for efficient screening of noble strains with secretion capabilities. The sorted strains were further confirmed their secretion from 50ml BHI medium cultivation. Overall, five remarkable strains has been discovered with different signal peptides and secretion abilities was confirmed in terms of protein expression.