Comparative transcriptome profiling of expression patterns and regulation mechanisms in the plant pathogen Burkholderia plantarii PG1 ; Vergleichende Transkriptomanalyse von Expressionsmustern und Regulationsmechanismen in dem Pflanzenpathogen Burkholderia plantarii PG1
Burkholderia plantarii PG1 (formerly glumae) is a model organism known as causal agent of bacterial panicle blight in rice plants and has become one of the most common seed-borne bacterial rice diseases in the world. Nevertheless, this organism has biological interest. First, B. plantarii PG1 is the producer of the extracellular lipase LipA to produce enantiopure pharmaceuticals. In addition, B. plantarii PG1 is a native rhamnolipid producer which is used in pharmaceutical, chemical, food and cosmetic industries. Furthermore, it is distinguished by a unique Quorum sensing system in Burkholderia and possesses more scientific interesting properties which were investigated in this work. The genome of B. plantarii PG1 contains a hydroxyethylthiazole kinase ThiM, which is part of a salvage pathway in the thiamine metabolism conceivably involved in the regulation of the endogenous CRISPR/CAS I-F system due to its unique genomic position upstream of the endonuclease Cas1. For further insights, a comparative transcriptome analysis was performed to elucidate possible effects of a ThiM deletion mutant. Different growth phases and media were investigated, resulting in significant transcriptional changes. In the first analysis of the transcription levels, the absence of the kinase ThiM increased the transcription of csy1-3 in LB medium and caused a decrease of csy1-3 in M9 minimal medium without thiamine. However, a comparative analysis demonstrated that the medium effect caused the transcriptional changes. Although this medium effect was present, an influence of the kinase ThiM on the regulation of the CRISPR/CAS I-F system could not be completely excluded. For further advances, a comparative transcriptome profiling should provide insights by identifying expression patterns and analysing metabolic networks under different conditions. The kinase ThiM is part of the salvage pathway in thiamine metabolism to produce thiamine pyrophosphate (TPP), the active form of thiamine. TPP is an essential cofactor in several metabolic ...