Q531L mutation in the capsid protein of hepatitis E virus genotype 1 causes infections in patients with altered immunity and immunosuppressive condition: Mechanism based on wet lab and in-silico findings

•A substitution (531Gln>Leu) occurred in the immunodominant E2s domain of HEV ORF2.•531Gln containing patients had higher serum ALT and viral loads than 531Leu (P < 0.01).•531Leu caused asymptomatic infections in the diabetic patients and pregnant women.•Predictably, 531Leu containing epitopes had stronger binding affinity than 531Gln.•531Leu virus could not cause infections in the immunocompetent hosts.