State of bacterial DNA after uptake into the roots of germinating barley seeds

• Main Author: Lawson, Larry Dale
• Format: Others
• Published: BYU ScholarsArchive 1973
• Subjects: DNA; Barley; Chemistry
• Online Access: https://scholarsarchive.byu.edu/etd/8297; https://scholarsarchive.byu.edu/cgi/viewcontent.cgi?article=9297&context=etd

Germinating barley seeds have been shown to take up Bacillus subtilis DNA labelled with 5-bromouracil and tritiated thymidine and retain the DNA in the root system without substantially degrading it. The percentage of bacterial DNA recovered from the total root DNA was independent of the amount of bacterial DNA available for uptake. Four observations indicated the stability of bacterial DNA after uptake into barley roots: (1) the bacterial DNA retained its transforming ability after recovery from the roots; (2) the labelled B. subtilis DNA showed similar CsCl density gradient patterns before uptake and after uptake; (3) most of the radioactivity of the total root DNA was found at the labelled B. subtilis DNA density positions upon CsCl gradient analysis; (4) barley seedlings that had taken up Micrococcus lysodeikticus DNA produced a new DNA form that underwent replication and which had a bouyant density intermediate between the bouyant densities of barley DNA and M. lysodeikticus DNA ( a verification of the results of Ledoux and Huart).