%A Mamedov,Tarlan %A Gurbuzaslan,Irem %A Yuksel,Damla %A Ilgin,Merve %A Mammadova,Gunay %A Ozkul,Aykut %A Hasanova,Gulnara %D 2021 %J Frontiers in Plant Science %C %F %G English %K ACE-2,SARS-CoV-2,Nicotiana benthamiana,Plant transient expression,Therapeutic agent %Q %R 10.3389/fpls.2021.742875 %W %L %M %P %7 %8 2021-December-06 %9 Original Research %# %! Soluble human angiotensin-converting enzyme 2 from Nicotiana benthamiana plant %* %< %T Soluble Human Angiotensin- Converting Enzyme 2 as a Potential Therapeutic Tool for COVID-19 is Produced at High Levels In Nicotiana benthamiana Plant With Potent Anti-SARS-CoV-2 Activity %U https://www.frontiersin.org/articles/10.3389/fpls.2021.742875 %V 12 %0 JOURNAL ARTICLE %@ 1664-462X %X The coronavirus disease 2019 (COVID-19) pandemic, which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has rapidly spread to more than 222 countries and has put global public health at high risk. The world urgently needs a safe, cost-effective SARS-CoV-2 vaccine as well as therapeutic and antiviral drugs to combat COVID-19. Angiotensin-converting enzyme 2 (ACE2), as a key receptor for SARS-CoV-2 infections, has been proposed as a potential therapeutic tool in patients with COVID-19. In this study, we report a high-level production (about ∼0.75 g/kg leaf biomass) of human soluble (truncated) ACE2 in the Nicotiana benthamiana plant. After the Ni-NTA single-step, the purification yields of recombinant plant produced ACE2 protein in glycosylated and deglycosylated forms calculated as ∼0.4 and 0.5 g/kg leaf biomass, respectively. The plant produced recombinant human soluble ACE2s successfully bind to the SARS-CoV-2 spike protein. Importantly, both deglycosylated and glycosylated forms of ACE2 are stable at increased temperatures for extended periods of time and demonstrated strong anti-SARS-CoV-2 activities in vitro. The half maximal inhibitory concentration (IC50) values of glycosylated ACE2 (gACE2) and deglycosylated ACE2 (dACE2) were ∼1.0 and 8.48 μg/ml, respectively, for the pre-entry infection, when incubated with 100TCID50 of SARS-CoV-2. Therefore, plant produced soluble ACE2s are promising cost-effective and safe candidates as a potential therapeutic tool in the treatment of patients with COVID-19.