The extinction temperature profile of parsley carrot leaf virus in 0.02 M (Na K) phosphate buffer, pH 7.2, containing 0.1 M NaCl, was determined. At the Td (dissociation temperature = 65°C), the point at which E260 begins to increase, the virus particles apparently dissociate to form RNA and empty protein shells (top component). At the Tf (temperature at the inflexion point of the curve = 70°C), corresponding to half the maximum increase in E260, the protein denatures and precipitates. Temperatures below Td have little effect on the virus, whereas temperatures higher than Tf also degrade the RNA. The results of the present work seem to suggest that the increase in E260 of PCLV preparations upon heating is mostly attributable to turbidity caused by coat protein denaturation rather than to effects on RNA.
Production of RNA and artificial top component from parsley carrot leaf virus heated in vitro
GALLITELLI, Donato
1977-01-01
Abstract
The extinction temperature profile of parsley carrot leaf virus in 0.02 M (Na K) phosphate buffer, pH 7.2, containing 0.1 M NaCl, was determined. At the Td (dissociation temperature = 65°C), the point at which E260 begins to increase, the virus particles apparently dissociate to form RNA and empty protein shells (top component). At the Tf (temperature at the inflexion point of the curve = 70°C), corresponding to half the maximum increase in E260, the protein denatures and precipitates. Temperatures below Td have little effect on the virus, whereas temperatures higher than Tf also degrade the RNA. The results of the present work seem to suggest that the increase in E260 of PCLV preparations upon heating is mostly attributable to turbidity caused by coat protein denaturation rather than to effects on RNA.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
