title: A comparison of DNA from free living and endosymbiotic Rhizobium leguminosarum (strain PRE).
abstract: 1. Bacteroids of Rhizobium leguminosarum (strain PRE) purified from root nodules of Pisum sativum (var. 'Rondo') by the standard procedure of differential centrifugation contained considerable contamination of mitochondrial material. This could be removed by incubation of the bacteroid preparation with 1 M KCl/1% deoxycholate. 2. The DNA content of bacteroid cells of R. leguminosarum was found to have increased about three fold in comparison with the DNA content of free living R. leguminosarum bacteria. 3. No significant difference in DNA composition of free living R. leguminosarum bacteria and bacteroids could be detected by CsCl equilibrium centrifugation, RNA - DNA hybridization and DNA - DNA reassociation studies.
mesh_terms: D001295:Atypical Bacterial Forms / Q000032:analysis; D004269:DNA, Bacterial / Q000032:analysis* / Q000378:metabolism; D003576:Electron Transport Complex IV / Q000378:metabolism; D009693:Nucleic Acid Hybridization; D009695:Nucleic Acid Renaturation; D010944:Plants / Q000032:analysis; D012231:Rhizobium / Q000032:analysis* / Q000378:metabolism; D013559:Symbiosis
chemical_list: D004269:DNA, Bacterial; D003576:Electron Transport Complex IV