Heme rescues a two-component system <it>Leptospira biflexa </it>mutant
<p>Abstract</p> <p>Background</p> <p>Heme is typically a major iron source for bacteria, but little is known about how bacteria of the <it>Leptospira </it>genus, composed of both saprophytic and pathogenic species, access heme.</p> <p>Results<...
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| Format: | Article |
| Language: | English |
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BMC
2008-01-01
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| Series: | BMC Microbiology |
| Online Access: | http://www.biomedcentral.com/1471-2180/8/25 |
| _version_ | 1811276700188672000 |
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| author | Picardeau Mathieu Betton Jean-Michel Louvel Hélène |
| author_facet | Picardeau Mathieu Betton Jean-Michel Louvel Hélène |
| author_sort | Picardeau Mathieu |
| collection | DOAJ |
| description | <p>Abstract</p> <p>Background</p> <p>Heme is typically a major iron source for bacteria, but little is known about how bacteria of the <it>Leptospira </it>genus, composed of both saprophytic and pathogenic species, access heme.</p> <p>Results</p> <p>In this study, we analysed a two-component system of the saprophyte <it>Leptospira biflexa</it>. <it>In vitro </it>phosphorylation and site-directed mutagenesis assays showed that Hklep is a histidine kinase which, after autophosphorylation of a conserved histidine, transfers the phosphate to an essential aspartate of the response regulator Rrlep. Hklep/Rrlep two-component system mutants were generated in <it>L. biflexa</it>. The mutants could only grow in medium supplemented with hemin or δ-aminolevulinic acid (ALA). In the pathogen <it>L. interrogans</it>, the <it>hklep </it>and <it>rrlep </it>orthologous genes are located between <it>hemE </it>and <it>hemL </it>genes, which encode proteins involved in heme biosynthesis. The <it>L. biflexa hklep </it>mutant could be complemented with a replicative plasmid harbouring the <it>L. interrogans </it>orthologous gene, suggesting that these two-component systems are functionally similar. By real-time quantitative reverse transcription-PCR, we also observed that this two-component system might influence the expression of heme biosynthetic genes.</p> <p>Conclusion</p> <p>These findings demonstrate that the Hklep/Rrlep regulatory system is critical for the <it>in vitro </it>growth of <it>L. biflexa</it>, and suggest that this two-component system is involved in a complex mechanism that regulates the heme biosynthetic pathway.</p> |
| first_indexed | 2024-04-13T00:01:22Z |
| format | Article |
| id | doaj.art-6147e8aa5a5c4824b3efd559640d66d1 |
| institution | Directory Open Access Journal |
| issn | 1471-2180 |
| language | English |
| last_indexed | 2024-04-13T00:01:22Z |
| publishDate | 2008-01-01 |
| publisher | BMC |
| record_format | Article |
| series | BMC Microbiology |
| spelling | doaj.art-6147e8aa5a5c4824b3efd559640d66d12022-12-22T03:11:20ZengBMCBMC Microbiology1471-21802008-01-01812510.1186/1471-2180-8-25Heme rescues a two-component system <it>Leptospira biflexa </it>mutantPicardeau MathieuBetton Jean-MichelLouvel Hélène<p>Abstract</p> <p>Background</p> <p>Heme is typically a major iron source for bacteria, but little is known about how bacteria of the <it>Leptospira </it>genus, composed of both saprophytic and pathogenic species, access heme.</p> <p>Results</p> <p>In this study, we analysed a two-component system of the saprophyte <it>Leptospira biflexa</it>. <it>In vitro </it>phosphorylation and site-directed mutagenesis assays showed that Hklep is a histidine kinase which, after autophosphorylation of a conserved histidine, transfers the phosphate to an essential aspartate of the response regulator Rrlep. Hklep/Rrlep two-component system mutants were generated in <it>L. biflexa</it>. The mutants could only grow in medium supplemented with hemin or δ-aminolevulinic acid (ALA). In the pathogen <it>L. interrogans</it>, the <it>hklep </it>and <it>rrlep </it>orthologous genes are located between <it>hemE </it>and <it>hemL </it>genes, which encode proteins involved in heme biosynthesis. The <it>L. biflexa hklep </it>mutant could be complemented with a replicative plasmid harbouring the <it>L. interrogans </it>orthologous gene, suggesting that these two-component systems are functionally similar. By real-time quantitative reverse transcription-PCR, we also observed that this two-component system might influence the expression of heme biosynthetic genes.</p> <p>Conclusion</p> <p>These findings demonstrate that the Hklep/Rrlep regulatory system is critical for the <it>in vitro </it>growth of <it>L. biflexa</it>, and suggest that this two-component system is involved in a complex mechanism that regulates the heme biosynthetic pathway.</p>http://www.biomedcentral.com/1471-2180/8/25 |
| spellingShingle | Picardeau Mathieu Betton Jean-Michel Louvel Hélène Heme rescues a two-component system <it>Leptospira biflexa </it>mutant BMC Microbiology |
| title | Heme rescues a two-component system <it>Leptospira biflexa </it>mutant |
| title_full | Heme rescues a two-component system <it>Leptospira biflexa </it>mutant |
| title_fullStr | Heme rescues a two-component system <it>Leptospira biflexa </it>mutant |
| title_full_unstemmed | Heme rescues a two-component system <it>Leptospira biflexa </it>mutant |
| title_short | Heme rescues a two-component system <it>Leptospira biflexa </it>mutant |
| title_sort | heme rescues a two component system it leptospira biflexa it mutant |
| url | http://www.biomedcentral.com/1471-2180/8/25 |
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