Three capsid amino acids notably influence coxsackie B3 virus stability

Coxsackievirus B3 strain 28 (CVB3/28) is less stable at 37 °C than eight other CVB3 strains with which it has been compared, including four in this study. In a variant CVB3/28 population selected for increased stability at 37 °C, the capsid proteins of the stable variant differed from the parental CVB3/28 by two mutations in Vp1 and one mutation in Vp3, each of which resulted in altered protein sequences. Each of the amino acid changes was individually associated with a more stable virus. Competition between CVB3/28 and a more stable derivative of the strain showed that propagation of the less stable virus was favoured in receptor-rich HeLa cells.