Enhancement of mitochondrial tyrosine kinase activity following viral transformation

A tyrosine protein kinase activity has been detected in the mitochondrial fraction purified from normal and virus-transformed cultured cells. The addition of serum to cells whose growth was restricted by serum limitation induced a marked decrease of tyrosine kinase activity associated with the mitochondrial fraction. At all the culture conditions tested this enzyme activity always resulted several fold higher in the virus-transformed cells than in the normal parental cells.