Polypeptide modification: An improved proglycinin design to stabilise oil-in-water emulsions

7Citations
Citations of this article
20Readers
Mendeley users who have this article in their library.

Abstract

β-Conglycinin and glycinin are soybean major seed storage proteins. Previous studies have shown that adding the extension region of β-conglycinin α subunit improves the emulsifying properties of proglycinin and confers more favourable characteristics than fusing the extension region of β-conglycinin α′ subunit or the hypervariable regions (A4IV) of glycinin A1aB1b subunit. To evaluate the polypeptide properties, we designed mutants of A1aB1b subunits fused with truncated versions of A4IV (A4IVcut), α (αcut) or α′ (α′cut) extension regions lacking the C-terminus 25 or 31 residues (A4IVC25, αC25 or α′C31), and also A4IVcut and α′cut with αC25 residues added (A4IVcut-αC25 and α′cut-αC25). All the modified proteins displayed conformations similar to the wild type. With good solubilities, the emulsion properties of the modified proteins were much better at ionic strength μ = 0.08 than at μ = 0.5. The modified A1aB1bαcut and A1aB1bα′cut showed poorer emulsion properties than those of A1aB1bα and A1aB1bα′. Replacing the hydrophobic A4IVC25 region of A1aB1bA4IV with hydrophilic αC25 created A1aB1bA4IVcut-αC25, which had the best emulsion stability among these proglycinin mutants. We found that addition of αC25 improves the emulsifying properties of two C-terminally truncated proglycinin variants, thereby illustrating its potential general utility. Our investigation showed that in order to improve the emulsifying ability and emulsion stability of a globular protein, the introduced polypeptide should (i) be highly hydrophilic, (ii) consist of multiple hydrophobic-strong hydrophilic regions comprising at least two alpha helixes, (iii) harbour a terminal α-helix at the end of the C-terminus and (iv) have properties similar to those of αC25.

Cite

CITATION STYLE

APA

Prak, K., Naka, M., Tandang-Silvas, M. R. G., Kriston-Vizi, J., Maruyama, N., & Utsumi, S. (2015). Polypeptide modification: An improved proglycinin design to stabilise oil-in-water emulsions. Protein Engineering, Design and Selection, 28(9), 281–291. https://doi.org/10.1093/protein/gzv031

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free