Use of Two-Dimensional Polyacrylamide Electrophoresis to Demonstrate that Putative Rhizobium Cross-Inoculation Mutants Actually Are Contaminants

Two-dimensional polyacrylamide electrophoresis was used to determine that mutants of Rhizobium trifolii DT6, claimed to be capable of effectively nodulating soybeans, were actually Rhizobium japonicum 110 contaminants isolated from the parent DT6 culture.