Incorporation of [3H]TTP into DNA by pea chloroplast extracts was highly dependent on the age of the tissue from which plastids were prepared. Catalytic activity was greatest in samples from 6- to 9-d-old plants; preparations ...

Isolated chloroplasts from Pisum sativum leaves catalyze [3H]thymidine incorporation into acid-insoluble material using light as the sole energy source. Neither ribonucleotides, deoxyribonucleotides nor deoxyribonucleosides ...