Lectin-like Intestinal Defensin Inhibits 2019-nCoV Spike binding to ACE2

Cheng Wang; Shaobo Wang; Daixi Li; Xia Zhao; Songling Han; Tao Wang; Gaomei Zhao; Yin Chen; Fang Chen; Jianqi Zhao; Liting Wang; Wei Sun; Yi Huang; Yongping Su; Dongqing Wei; Jinghong Zhao; Junping Wang

The copyright holder for this preprint (which was not peer-reviewed) is the . https://doi.org/10.1101/2020.03.29.013490 doi: bioRxiv preprint calculated using the molecular mechanics-Poisson-Boltzmann surface area (MM-PBSA) method with g_mmpbsa procedure for Gromacs 48, 49 . The binding free energy was calculated using 500 snapshots sampled every 10 ps from total 5 ns trajectory. Western blot. Caco-2 cells were seeded into a 6-well plate at a density of 1×10 6 cells/well. Cells preincubated with different concentrations of HD5 (10, 50, and 100 μg/mL) at 37 o C for 15 min were exposed to 20 μg/mL of 2019-nCoV S1 containing His-tag at 4 o C for 1 h. After three times of wash with PBS, cells were collected and processed with RIPA lysis and extraction buffer (89900, Thermo Fisher Scientific). S1 content was measured by determining the band thickness as we previously described 50 . A primary anti-His-tag mouse monoclonal antibody (AF5060, Beyotime, 1:1000) and a goat anti-mouse secondary antibody (A0216, Beyotime, 1:2000) were employed to detect S1. β-actin determined by a mouse monoclonal antibody (AA128, Beyotime, 1:1000) was used as a reference.