The COVID-19 pandemic has led to accelerated efforts to develop therapeutics and vaccines. A key target of these efforts is the spike (S) protein, which is metastable and difficult to produce recombinantly. Here, we characterized 100 structure-guided spike designs and identified 26 individual substitutions that increased protein yields and stability. Testing combinations of beneficial substitutions resulted in the identification of HexaPro, a variant with six beneficial proline substitutions exhibiting ~10-fold higher expression than its parental construct and the ability to withstand heat stress, storage at room temperature, and three freeze-thaw cycles. A 3.2 Å-resolution cryo-EM structure of HexaPro confirmed that it retains the prefusion spike conformation. High-yield production of a stabilized prefusion spike protein will accelerate the development of vaccines and serological diagnostics for SARS-CoV-2.
【초록키워드】 SARS-CoV-2, Vaccine, Stress, Vaccines, COVID-19 pandemic, variant, diagnostics, Spike protein, Protein, Testing, stability, temperature, serological, expression, Combination, effort, Substitution, prefusion, HexaPro, cryo-EM structure, develop, characterized, parental, accelerate, accelerated, exhibiting, freeze-thaw cycles, proline substitution, 【제목키워드】 SARS-CoV-2 spike,