Rhizobium japonicum derivatives differing in nitrogen-fixing efficiency and carbohydrate utilization.

摘要: Four derivatives of Rhizobium japonicum 110 were isolated on the basis morphologically different colonies formed yeast extract-mannitol-HM salts medium. All are able to nodulate Lee soybeans. The bacteria-plant associations by each clone have measurable acetylene-reducing activity, but those two these clones (designated L1-110 and L2-110) 5- 10-fold less efficient than others I-110 S-110). These not detectable with ordinary culture techniques since, because cell adherence, genetically mixed result. When a detergent (Tween 40 at 0.01%, vol/vol) was added dilution medium, separate resulted. metabolic for gross differences in colony morphology medium found be that L2-110 utilized p-mannitol growth, whereas S-110 did not. differ analogously ability utilize D-arabitol. Clones chosen studies growth rates various carbohydrates. Although number sugars, such as gluconate, arabinose, glycerol, mannose, they differed glucose fructose. grew faster L1-110, fructose I-110. showed identical responses several antibiotics deoxyribonucleic acid (DNA) synthesis inhibitors susceptibility some highly specific bacteriophages. Identical buoyant densities their DNAs isopycnic CsCl density gradients thermal denaturation temperatures suggest same DNA base composition. Preliminary DNA/DNA hybridization experiments show strain high degree common polynucleotide sequences.