Comparative in situ analysis of ipdC–gfpmut3 promoter fusions of Azospirillum brasilense strains Sp7 and Sp245
Open Access
- 25 July 2005
- journal article
- research article
- Published by Wiley in Environmental Microbiology
- Vol. 7 (11), 1839-1846
- https://doi.org/10.1111/j.1462-2920.2005.00848.x
Abstract
Inoculation of wheat roots with Azospirillum brasilense results in an increase of plant growth and yield, which is proposed to be mainly due to the bacterial production of indole‐3‐acetic acid in the rhizosphere. Field inoculation experiments had revealed more consistent plant growth stimulation using A. brasilense strain Sp245 as compared with the strain Sp7. Therefore, the in situ expression of the key gene ipdC (indole‐3‐pyruvate decarboxylase) was examined in these two strains. Within the ipdC promoter of strain Sp245 a region of 150 bases was identified, which was missing in strain Sp7. Thus, three different translational ipdC promoter fusions with gfpmut3 were constructed on plasmid level: the first contained the part of the Sp245 promoter region homologous to strain Sp7, the second was bearing the complete promoter region of Sp245 including the specific insertion and the third comprised the Sp7 promoter region. By comparing the fluorescence levels of these constructs after growth on mineral medium with and without inducing amino acids, it could be demonstrated that ipdC expression in A. brasilense Sp245 was subject to a stricter control compared with strain Sp7. Microscopic detection of these reporter strains colonizing the rhizoplane documented for the first time an in situ expression of ipdC.Keywords
This publication has 35 references indexed in Scilit:
- Transcriptional Analysis of the Azospirillum brasilense Indole-3-Pyruvate Decarboxylase Gene and Identification of a cis-Acting Sequence Involved in Auxin Responsive ExpressionMolecular Plant-Microbe Interactions®, 2005
- Surface Characteristics ofAzospirillum brasilensein Relation to Cell Aggregation and Attachment to Plant RootsCritical Reviews in Microbiology, 2000
- Use of Green Fluorescent Protein to Detect Expression of nif Genes of Azoarcus sp. BH72, a Grass-Associated Diazotroph, on Rice RootsMolecular Plant-Microbe Interactions®, 1998
- Four new derivatives of the broad-host-range cloning vector pBBR1MCS, carrying different antibiotic-resistance cassettesGene, 1995
- Azospirillum brasilenseIndole-3-Acetic Acid Biosynthesis: Evidence for a Non-Tryptophan Dependent PathwayMolecular Plant-Microbe Interactions®, 1993
- Growth response of maize roots to Azospirillum inoculation: Effect of soil organic matter content, number of rhizosphere bacteria and timing of inoculationSoil Biology and Biochemistry, 1988
- Wheat inoculation withAzospirillum brasilenseSp6 and some mutants altered in nitrogen fixation and indole-3-acetic acid productionFEMS Microbiology Letters, 1986
- Sites and processes of association between diazotrophs and grassesCanadian Journal of Microbiology, 1983
- Isolation and characterization of Azospirillum mutants excreting high amounts of indoleacetic acidCanadian Journal of Microbiology, 1983
- A taxonomic study of the Spirillum lipoferum group, with descriptions of a new genus, Azospirillum gen. nov. and two species, Azospirillum lipoferum (Beijerinck) comb. nov. and Azospirillum brasilense sp. nov.Canadian Journal of Microbiology, 1978