title: darR and darS are regulatory genes that modulate 2-hexyl, 5-propyl resorcinol transcription in Pseudomonas chlororaphis PCL1606.
abstract: Pseudomonas chlororaphis PCL1606 synthesizes the antifungal antibiotic 2-hexyl, 5-propyl resorcinol (HPR), which is crucial for the biocontrol of fungal soil-borne pathogens. The genetic basis for HPR production lies in the dar genes, which are directly involved in the biosynthesis of HPR. In the present study, we elucidated the genetic features of the dar genes. Reverse transcription PCR experiments revealed an independent organization of the dar genes, except for darBC, which was transcribed as a polycistronic mRNA. In silico analysis of each gene revealed putative promoters and terminator sequences, validating the proposed gene arrangement. Moreover, experiments utilizing 5' rapid amplification of cDNA ends were used to determine the transcriptional initiation sites for the darA, darBC, darS and darR gene promoters, and subsequently to confirm the functionality of these regions. The results of quantitative real-time PCR experiments indicated that biosynthetic dar genes were not only modulated through the global regulator gacS, but also through darS and darR. The interplay between darS and darR revealed transcriptional cross-inhibition. However, these results also showed that other regulatory parameters play a role in HPR production, such as the environmental conditions and additional regulatory genes.
authors.affiliation: Instituto de Hortofruticultura Subtropical y Mediterránea 'La Mayora', Universidad de Málaga, Consejo Superior de Investigaciones Científicas. Departamento de Microbiología, Facultad de Ciencias, Campus de Teatinos s/n, 29071 Málaga, Spain.
authors.forename: Claudia E
authors.initials: CE
authors.lastname: Calderón
authors.affiliation: Instituto de Hortofruticultura Subtropical y Mediterránea 'La Mayora', Universidad de Málaga, Consejo Superior de Investigaciones Científicas. Departamento de Microbiología, Facultad de Ciencias, Campus de Teatinos s/n, 29071 Málaga, Spain.
authors.forename: Víctor J
authors.initials: VJ
authors.lastname: Carrión
authors.affiliation: Instituto de Hortofruticultura Subtropical y Mediterránea 'La Mayora', Universidad de Málaga, Consejo Superior de Investigaciones Científicas. Departamento de Microbiología, Facultad de Ciencias, Campus de Teatinos s/n, 29071 Málaga, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: de Vicente
authors.affiliation: Instituto de Hortofruticultura Subtropical y Mediterránea 'La Mayora', Universidad de Málaga, Consejo Superior de Investigaciones Científicas. Departamento de Microbiología, Facultad de Ciencias, Campus de Teatinos s/n, 29071 Málaga, Spain.
authors.forename: Francisco M
authors.initials: FM
authors.lastname: Cazorla
mesh_terms: D053898:Biosynthetic Pathways / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D005809:Genes, Regulator; D011401:Promoter Regions, Genetic; D011549:Pseudomonas / Q000235:genetics / Q000378:metabolism*; D060888:Real-Time Polymerase Chain Reaction; D012118:Resorcinols / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D024363:Transcription Initiation Site; D014158:Transcription, Genetic; D059467:Transcriptome
chemical_list: D012118:Resorcinols; C011600:2-n-hexyl-5-n-propylresorcinol