Genetic Analysis of a pH-Regulated Operon from Rhizobium tropici CIAT899 Involved in Acid Tolerance and Nodulation Competitiveness
Rhizobium tropici CIAT899 is highly acid tolerant and a good competitor for Phaseolus vulgaris nodule occupancy at low pH values. Using Tn5 mutagenesis, we identified an operon required for acid tolerance and nodulation competitiveness. The insertion was mapped to the 5′ end of atvA, encoding a prod...
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| Format: | Article |
| Language: | English |
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The American Phytopathological Society
2003-02-01
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| Series: | Molecular Plant-Microbe Interactions |
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| Online Access: | https://apsjournals.apsnet.org/doi/10.1094/MPMI.2003.16.2.159 |
| _version_ | 1831544243459457024 |
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| author | Pablo Vinuesa Frauke Neumann-Silkow Cristina Pacios-Bras Herman P. Spaink Esperanza Martínez-Romero Dietrich Werner |
| author_facet | Pablo Vinuesa Frauke Neumann-Silkow Cristina Pacios-Bras Herman P. Spaink Esperanza Martínez-Romero Dietrich Werner |
| author_sort | Pablo Vinuesa |
| collection | DOAJ |
| description | Rhizobium tropici CIAT899 is highly acid tolerant and a good competitor for Phaseolus vulgaris nodule occupancy at low pH values. Using Tn5 mutagenesis, we identified an operon required for acid tolerance and nodulation competitiveness. The insertion was mapped to the 5′ end of atvA, encoding a product with high sequence identity to the agrobacterial AcvB virulence protein. Complementation analyses indicated that atvA is an ortholog of acvB, both genes being required for acid tolerance. A Ser/Ala substitution in the LIPASE_SER motif of AtvA resulted in an acid sensitive Fix+ but very poorly competing strain, demonstrating that Ser-313 is essential for AtvA function. atvA is the second gene in an operon that is transcriptionally upregulated by acid shock. The acid-responsive promoter was mapped to a 469-bp intergenic region located upstream of lpiA, the first gene in the operon. lpiA-like genes are found in several α, β, and γ Proteobacteria that interact with eukaryotic host cells, and they are predicted to encode membrane proteins related to the FmtC/MprF family from low G+C Firmicutes. The latter proteins are involved in resistance to cationic antimicrobial peptides. A nonpolar deletion in lpiA caused a sevenfold decrease in relative nodulation competitiveness. |
| first_indexed | 2024-12-17T01:06:10Z |
| format | Article |
| id | doaj.art-28ba65d2d62d4712a072125bf992c175 |
| institution | Directory Open Access Journal |
| issn | 0894-0282 1943-7706 |
| language | English |
| last_indexed | 2024-12-17T01:06:10Z |
| publishDate | 2003-02-01 |
| publisher | The American Phytopathological Society |
| record_format | Article |
| series | Molecular Plant-Microbe Interactions |
| spelling | doaj.art-28ba65d2d62d4712a072125bf992c1752022-12-21T22:09:15ZengThe American Phytopathological SocietyMolecular Plant-Microbe Interactions0894-02821943-77062003-02-0116215916810.1094/MPMI.2003.16.2.159Genetic Analysis of a pH-Regulated Operon from Rhizobium tropici CIAT899 Involved in Acid Tolerance and Nodulation CompetitivenessPablo VinuesaFrauke Neumann-SilkowCristina Pacios-BrasHerman P. SpainkEsperanza Martínez-RomeroDietrich WernerRhizobium tropici CIAT899 is highly acid tolerant and a good competitor for Phaseolus vulgaris nodule occupancy at low pH values. Using Tn5 mutagenesis, we identified an operon required for acid tolerance and nodulation competitiveness. The insertion was mapped to the 5′ end of atvA, encoding a product with high sequence identity to the agrobacterial AcvB virulence protein. Complementation analyses indicated that atvA is an ortholog of acvB, both genes being required for acid tolerance. A Ser/Ala substitution in the LIPASE_SER motif of AtvA resulted in an acid sensitive Fix+ but very poorly competing strain, demonstrating that Ser-313 is essential for AtvA function. atvA is the second gene in an operon that is transcriptionally upregulated by acid shock. The acid-responsive promoter was mapped to a 469-bp intergenic region located upstream of lpiA, the first gene in the operon. lpiA-like genes are found in several α, β, and γ Proteobacteria that interact with eukaryotic host cells, and they are predicted to encode membrane proteins related to the FmtC/MprF family from low G+C Firmicutes. The latter proteins are involved in resistance to cationic antimicrobial peptides. A nonpolar deletion in lpiA caused a sevenfold decrease in relative nodulation competitiveness.https://apsjournals.apsnet.org/doi/10.1094/MPMI.2003.16.2.159gusAlipolytic enzymessymbiosis |
| spellingShingle | Pablo Vinuesa Frauke Neumann-Silkow Cristina Pacios-Bras Herman P. Spaink Esperanza Martínez-Romero Dietrich Werner Genetic Analysis of a pH-Regulated Operon from Rhizobium tropici CIAT899 Involved in Acid Tolerance and Nodulation Competitiveness Molecular Plant-Microbe Interactions gusA lipolytic enzymes symbiosis |
| title | Genetic Analysis of a pH-Regulated Operon from Rhizobium tropici CIAT899 Involved in Acid Tolerance and Nodulation Competitiveness |
| title_full | Genetic Analysis of a pH-Regulated Operon from Rhizobium tropici CIAT899 Involved in Acid Tolerance and Nodulation Competitiveness |
| title_fullStr | Genetic Analysis of a pH-Regulated Operon from Rhizobium tropici CIAT899 Involved in Acid Tolerance and Nodulation Competitiveness |
| title_full_unstemmed | Genetic Analysis of a pH-Regulated Operon from Rhizobium tropici CIAT899 Involved in Acid Tolerance and Nodulation Competitiveness |
| title_short | Genetic Analysis of a pH-Regulated Operon from Rhizobium tropici CIAT899 Involved in Acid Tolerance and Nodulation Competitiveness |
| title_sort | genetic analysis of a ph regulated operon from rhizobium tropici ciat899 involved in acid tolerance and nodulation competitiveness |
| topic | gusA lipolytic enzymes symbiosis |
| url | https://apsjournals.apsnet.org/doi/10.1094/MPMI.2003.16.2.159 |
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