Expression and Purification of Recombinant Duck Ovalbumin in Escherichia coli

Abstract

Ovalbumin (OVA) is a major egg white protein with a balanced amino acid profile and high digestibility, making it valuable for pharmaceutical, nutritional, and health applications. Recombinant production of ovalbumin provides a sustainable and consistent protein source that may reduce allergenic risks and offer alternatives suitable for vegetarian consumers. This study aimed to express duck ovalbumin protein in Escherichia coli as an alternative protein source. Total mRNA was isolated from duck ovarian tissue, reverse-transcribed into cDNA, and the OVA coding sequence was cloned from pGEMT-OVA into the pET28a expression vector. The constructed vector was transformed into E. coli BL21 (DE3) pLysS and E. coli (DE3) Rosetta strains. Recombinant ovalbumin was successfully expressed with an estimated molecular weight of ~45 kDa. Optimal protein production was achieved with induction using 0.25 mM isopropyl-β-D-1-thiogalactopyranoside (IPTG). Purification steps were required to isolate recombinant ovalbumin from host proteins, confirming the feasibility of microbial systems for sustainable OVA production.