Fig. 5. Distribution of Hsp60 A144V mutant protein in sucrose gradients. Sucrose gradients of an equal amount of lysed purified mitochondria (1 mg of proteins) from W303-1B cells expressing the wild-type Hsp60 protein or the Hsp60 A144V mutant grown in glucose and glycerol-containing medium were collected in 16 fractions. The gradient fractions were probed for the presence of proteins Hsp60, Abf2, Mdh1, (A) and mtDNA (B). Mdh1 is a matrix protein, which represents the control for the total lysis of mitochondria and the presence of matrix contamination. The combined occurrence of Abf2 and mtDNA indicates gradient fractions that contain nucleoids. An increased presence of Hsp60 A144V mutant protein in fractions containing nucleoids is visible. A much longer exposure time is required to detect the wild-type Hsp60 protein associated with nucleoids (compare with Fig. 4A).