Method for selecting mutants of legume-nodulating bacteria enhanced in competition
US5432079A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 11, 1988 |
| Grant date | Jul 11, 1995 |
| Priority date | — |
| Expiry date | Mar 11, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S435/878
- WIPO fieldBiotechnology
- WIPO sectorChemistry
Abstract
Methods for the isolation of mutant rhizobial strains with improved competition of nodulation (Comp.sup.+) is presented. Mutants are selected for constitutive expression of inducible nod genes (in the absence of inducer) and screened for hyperinduction of nod genes in the presence of inducer. Mutants which are defective in nodulation or in symbiotic nitrogen fixation are eliminated from further testing. Selections for constitutive nod expression and for hyperinduction of nod genes are facilitated by the use of plasmid carrying a selectable marker fused to an inducible nod gene and a plasmid carrying a reporter gene fused downstream of an inducible nod gene. The methods exemplified are particularly useful for the isolation and identification of Comp.sup.+ mutants of Bradyrhizobium japonicum.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.