An improved adenosine triphosphatase assay for physical particles of avian myeloblastosis virus (AMV)

SummaryThe adenosine triphosphatase (ATPase) assay for avian myeloblastosis virus (AMV) was modified to produce greater sensitivity and reproducibility. With the new assay, and virus cultivated in vitro, the relationship between adenosine triphosphatase activity and virus concentation was linear between 1 × 1012 and 1 × 108 particles/ml. This assay was, however, tenfold less sensitive when virus in avian plasma was assayed. Rate zonal and equilibrium density gradient centrifugation experiments confirmed the specificity of the reaction.We are greatly indebted to Drs. Joseph and Dorothy Beard for providing initial stocks of virus and of myeloblasts, and for generous gifts of time and hospitality involved in introducing us to the methodology of work with avian myeloblastosis. Skilled and conscientious technical assistance was provided by Miss Kathleen Burke and Mrs. Eva Zanati.