The Lubrizol Corporation

Mycogen Plant Science, Inc.

Michael A Djordjevic

Barry G Rolfe

John M Watson

Kieran F Scott

Peter R Schofield

John W Redmond

Peter L Kuempel

Michael Batley

Roger W Innes

The invention includes a consensus nucleotide sequence found in the promoter regions of those Rhizobium and Bradyrhizobium nodulation genes which are activated by chemical inducer(s) in legume exudate. A promoter comprising the consensus sequence is a legume exudate-inducible promoter. A recombinant gene comprising a structural gene and a legume exudate-inducible promoter is selectively expressed in the presence of legume exudate or chemical inducer(s) and a functional nodD gene. The consensus nucleotide sequence is ATCCAYNNYGYRGATGNWYKYKATCSAAWCAATCRATTTTACCARWYYKNSRR where

Nodulation gene promoter

Nodulation gene-inducing factors have been isolated and identified. A number of substituted flavones, some of which are components of exudates and extracts of leguminous plants, have been found to induce expression of certain nodulation genes in Rhizobium strains. Three components of clover extract 7,4'-dihydroxyflavone, 7,4'-dihydroxy-3'methoxyflavone, and 4'-hydroxy-7-methoxyflavone have been identified as nodulation inducers of certain Rhizobium trifolii nod genes. A number of other flavonoids including flavones, flavanones, flavanols and dihydroflavanols, not necessarily found in legume exudates, were also found to induce expression of certain nodulation genes.

Nodulation inducing factors

Growing community of inventors

Aranda, Australia

Michael A Djordjevic