Structure- and Design-Based Difficulties in Recombinant Protein Purification in Bacterial Expression

Abstract

Protein purification is not a simple task. Yet, overexpression at bacterial systems with recombinant modifications brings further difficulties. Adding a tag, an affinity label, and expressing particular domains of the whole protein, especially hydrophobic sections, make purification a challenging process. Protein folding pattern may perturb N- or C-terminal tag and this terminal preference may lead to poor purification yield. Codon optimization, solvent content and type, ionic conditions, resin types, and self-cleavage of recombinant proteins bring further difficulties to protein expression and purification steps. The chapter overviews problems of protein purification through a small peptide overexpression in bacteria (Recombinant anti-SARS Coronavirus 2 (SARS-Cov-2) Spike protein Receptor Binding Domain (RBD) antibody (Clone Sb#14). The chapter also covers troubleshooting at distinct steps and highlights essential points to solve crucial issues of protein purification.