On the DNA Content of the Bacteroids of Rhizobium japonicum
نویسنده
چکیده
DNA Content, Nodules, Bacteroids, Rhizobium, Soybean The DNA content of bacteroids from large nodules of soybean plants infected with Rhizobium japonicum strain 61 -A -101 was found to be 1.20 x 10~14 g per cell. Bacteroids from smaller nodules had slightly less DNA as did the stationary phase, free-living cells; both giving a value of 0.92 x 10-14 g per cell. In comparing these data with those of other workers it was found that there is little evidence to support suggestions that bacteroids possess anything less than a full genetic complement of DNA and that some misinterpretation of older published data has occurred.
منابع مشابه
Proton motive force in washed cells of Rhizobium japonicum and bacteroids from Glycine max.
The components of the proton motive force (delta p), namely the membrane potential and the transmembrane pH gradient, were measured in washed cells of Rhizobium japonicum CC705 grown in cultures (5% O2-95% N2) in the presence of 10 mM KNO3 and in bacteroids from Glycine max. The delta p and its components remained reasonably constant in cells as well as in bacteroids at various stages of growth...
متن کاملDifferentiation of Rhizobium japonicum. II. Enzymatic Activities in Bacteroids and Plant Cytoplasm during the Development of Nodules of Glycine max
Phytotron grown plants of Glycine max var. Caloria infected with Rhizobium japonicum 61-A-101 under controlled conditions as 14 d old seedlings develop a sharp maximum of nitrogenase activity of 13 i 3 nmol C2H4-h—'-mg nodule fresh weight1 19 d after infection, followed by a long period of reduced activity (3 —5 nmol) between 30 and 45 days after infection. A higher maximum activity (18 nmol C2...
متن کاملDNA content of free living rhizobia and bacteroids of various Rhizobium-legume associations.
The DNA content of bacteroids from 22 different Rhizobium-legume associations was compared to that of the corresponding free living Rhizobium species using laser flow microfluorometry. In all 18 effective associations, the bacteroids had either similar or higher DNA content than the free living rhizobia. Bacteroid populations isolated from effective clover (Trifolium repens) and alfalfa (Medica...
متن کاملDifferentiation of Rhizobium japonicum, I. enzymatic comparison of nitrogenase repressed and derepressed free living cells and of bacteroids.
Derepressed free living cells of Rhizobium japonicum strain 61-A-101 with leucine as single nitrogen source develop a maximum nitrogenase activity of 180 nmol C2H4.mg protein -1.H-1 in liquid culture under 2% 2% O2 in the gas phase. Only 10% of this activity is found with no oxygen in the gas phase during a 90 min incubation period. The maximum activity under 2% oxygen in the gas phase is unaff...
متن کاملOxyleghemoglobin-mediated Hydrogen Oxidation by Rhizobium japonicum USDA 122 DES Bacteroids.
Oxyleghemoglobin was used to supply low concentrations of O(2) to H(2)-oxidizing bacteroids from Rhizobium japonicum USDA 122 DES. The H(2) oxidation system of these bacteroids was capable of effectively utilizing O(2) at the low concentrations of O(2) expected to be found in soybean nodules. Apparent K(m) values of approximately 10 nanomolar O(2) have been calculated for the oxyhydrogen reacti...
متن کامل