Project description:Background: Pantoea ananatis LMG 2665T synthesizes and utilizes acyl homoserine lactones (AHLs) for signaling. In this strain, short chain AHLs (C4 to C8) are produced by the EanI/R quorum sensing (QS) system that is involved in pathogenicity and biofilm formation. The complete set of genes regulated by the EanI/R system in P. ananatis LMG 2665T is still not fully known. In the present study, RNA-seq was used to analyze the transcriptome profiles controlled by the EanI/R system in this strain by comparing the wild type strain and its QS mutant 2665T ean∆I/R during lag and log stages. The RNA seq data was validated by RT qPCR. Results: The results showed that the EanI/R regulon in P. ananatis LMG 2665T comprised 144 genes, constituting 3.3% of the whole transcriptome under the experimental conditions in this study. The majority of genes regulated by the EanI/R system included genes for flagella assembly, bacterial chemotaxis, pyruvate metabolism, two component system, metabolic pathways, microbial metabolism and biosynthesis of secondary metabolites. Conclusions: This is the first study to identify the EanI/R QS regulon in P. ananatis LMG 2665T. Functional analysis of genes regulated the EanI/R system in LMG 2665T could help unveil genes that play a vital role in pathogenesis and survival strategies of this pathogen.
Project description:The purpose of the study is to identify Irr-responsive genes in the bacterium Bradyrhizobium japonicum. Parent strain LO was compared to irr mutant strain LODTM5 by whole genome microarray analysis. Both cell types were grown in iron-limited media. Keywords: Comparison of B. japonicum wild type and mutant cells
Project description:The purpose of the study is to identify iron-responsive genes in the bacterium Bradyrhizobium japonicum. Parent strain LO was grown under iron limitation or under iron sufficiency and compared to each other by whole genome microarray analysis. Keywords: Comparison of cells grown under low or high iron conditons
Project description:Many sulfur-oxidizing prokaryotes oxidize sulfur compounds through a combination of initial extracytoplasmic and downstream cytoplasmic reactions. Facultative sulfur oxidizers adjust transcription to sulfur availability. While sulfur-oxidizing enzymes and transcriptional repressors have been extensively studied, sulfur import into the cytoplasm and how regulators sense external sulfur are poorly understood. Addressing this gap, we show that SoxT1A and SoxT1B, which resemble YeeE/YedE-family thiosulfate transporters and are encoded alongside sulfur oxidation and transcriptional regulation genes, fulfill these roles in the Alphaproteobacterium Hyphomicrobium denitrificans. RT-qPCR provided initial evidence that SoxT1A and SoxT1B from H. denitrificans may be intricate components of the oxidation pathway and/or involved in its transcriptional regulation. Here, we extend these analyses with genome-wide mRNA-Seq data for the reference strain, comparing transcription in the absence and presence of 2 mM thiosulfate