Lectin I from Bauhinia variegata (BVL-I) expressed by Pichia pastoris inhibits initial adhesion of oral bacteria in vitro

Int J Biol Macromol. 2016 Dec;93(Pt A):913-918. doi: 10.1016/j.ijbiomac.2016.09.062. Epub 2016 Sep 17.

Abstract

Lectins are non-immune proteins that reversibly bind to carbohydrates in a specific manner. Bauhinia variegata lectin I (BVL-I) is a Gal/GalNAc-specific, single-chain lectin isolated from Bauhinia variegata seeds that has been implicated in the inhibition of bacterial adhesion and the healing of damaged skin. Since the source of the native protein (nBVL) is limited, this study aimed to produce recombinant BVL-I in Pichia pastoris (rBVL-Ip). The coding sequence for BVL-I containing preferential codons for P. pastoris was cloned into the pPICZαB plasmid. A single expressing clone was selected and fermented, resulting in the secretion and glycosylation of the protein. Fed-batch fermentation in 7L-scale was performed, and the recombinant lectin was purified from culture supernatant, resulting in a yield of 1.5mg/L culture. Further, rBVL-Ip was compared to nBVL and its recombinant version expressed in Escherichia coli BL21 (DE3) (rBVL-Ie). Although it was expressed as a monomer, rBVL-Ip retained its biological activity since it was able to impair the initial adhesion of Streptococcus mutans and S. sanguinis in an in vitro model of biofilm formation and bacterial adhesion. In summary, rBVL-Ip produced in Pichia pastoris represents a viable alternative to large-scale production, encouraging further biological application studies with this lectin.

Keywords: Legume lectin; Oral bacteria; Recombinant lectin.

MeSH terms

  • Animals
  • Anti-Bacterial Agents / biosynthesis
  • Anti-Bacterial Agents / pharmacology*
  • Bacterial Adhesion / drug effects*
  • Bauhinia / chemistry*
  • Erythrocytes / drug effects
  • Escherichia coli
  • Hemagglutination
  • Humans
  • Pichia / metabolism
  • Plant Lectins / biosynthesis
  • Plant Lectins / pharmacology*
  • Rabbits
  • Saliva / microbiology
  • Streptococcus mutans / drug effects
  • Streptococcus sanguis / drug effects

Substances

  • Anti-Bacterial Agents
  • Plant Lectins