Aromatic residues in the oligonucleotide binding domain are essential to the function of the single-stranded DNA binding protein of Helicobacter pylori.

Single-stranded DNA-binding protein (SSB) is essential to DNA replication, DNA repair, and homologous genetic recombination. Our previous study on the crystal structure of a C-terminally truncated SSB from Helicobacter pylori, HpSSBc, in complex with single-stranded DNA (ssDNA) suggests that several aromatic residues, including Phe37, Phe50, Phe56, and Trp84, were involved in ssDNA binding. To investigate the importance of these aromatic residues, the binding activity of four site-directed HpSSB mutants, including F37A HpSSB, F50A HpSSB, F56A HpSSB, and W84A HpSSB, was compared to that of wild-type HpSSB and HpSSBc by means of electrophoresis mobility shift assay (EMSA), tryptophan quenching fluorescence titration, and surface plasmon resonance (SPR).

Targeting the receptor binding domain and heparan sulfate binding for antiviral drug development against SARS-CoV-2 variants.

The emergence of SARS-CoV-2 variants diminished the efficacy of current antiviral drugs and vaccines. Hence, identifying highly conserved sequences and potentially druggable pockets for drug development was a promising strategy against SARS-CoV-2 variants. In viral infection, the receptor-binding domain (RBD) proteins are essential in binding to the host receptor.