Fig. 2

Alignment and surface potential analysis of crucial amino acids in NRP1 proteins. (A) Comparative analysis of the residues of NRP1s at the interface binding to the spike protein of SARS-CoV-2 from human (GenBank accession no. XP_006717584.1), rhesus (GenBank accession no. NP_001252745.1), hamster (GenBank accession no. XP_040590606), mouse (GenBank accession no. NP_033491), ferret (GenBank accession no. XP_004774343.2), mink (GenBank accession no. XP_044082878.1), and Gallus (GenBank accession no. NP_990113.1). The NRP1 residues at positions 35, 46, and 90 are marked in blue triangles. (B) Surface potential diagram of interface zone of NRP1s. The structural superposition of the NRP1 region 26–141 from human (yellow, PDB code 7m0r), rhesus (violet), hamster (purple), mouse (gray), ferret (cyan), mink (red), and chickens (green). The NRP1 structures of chickens, rhesus, hamster, ferret, and mink were modeled using the homology models of human NRP1 (PDB code 7m0r) as the template by SWISS-MODEL (https://swissmodel.expasy.org/). The three key differential residues of NRP1 interacting with the spike protein of SARS-CoV-2 are represented by yellow sticks in the structural superposition; the black dash line circled key residues in the potential surface diagram. The electrostatic potential color range is -/+5