Vasil I K, Giles K L
Science. 1975 Nov 14;190(4215):680. doi: 10.1126/science.127380.
Chloroplasts isolated from spinach leaves have been transferred in large numbers into protoplasts of Neurospora crassa with the help of polyethylene glycol. The chloroplasts show high photosynthetic activity--at least until the time of uptake--and the protoplasts continue to show active cytoplasmic streaming after chloroplast uptake.