Project description:We show for soil bacterium Enterobacter soli LF7 (synonym Enterobacter asburiae LF7a) that possession of a iac (indole 3-acetic acid catabolic) gene cluster is causatively linked to the ability to utilize the plant hormone indole 3-acetic acid (IAA) as a carbon and energy source. Genome-wide transcriptional profiling by mRNA sequencing revealed that these iac genes chromosomally arranged as iacHABICDEFG and coding for the transformation of IAA to catechol, were the most highly induced (>29-fold) among the relatively few (<1%) differentially expressed genes in response to IAA. Also highly induced and immediately downstream of the iac cluster were genes for a Major Facilitator Superfamily protein (mfs) and enzymes of the β-ketoadipate pathway (pcaIJD-catBCA), which channels catechol into central metabolism. This entire iacHABICDEFG-mfs-pcaIJD-catBCA gene set was constitutively expressed in a iacR deletion mutant, confirming the role of iacR, annotated as coding for a MarR-type regulator and located upstream of iacH, as a repressor of iac gene expression. The research described here was funded from grants #2010-03544 and #2013-02075 awarded to JHJL by the United States Department of Agriculture (USDA) National Institute of Food and Agriculture (NIFA) Agriculture and Food Research Initiative (AFRI)
Project description:Global warming and heat stress belong to the most critical environmental challenges to agriculture worldwide, causing severe losses of major crop yields. In present study we report that the endophytic bacterium Enterobacter sp. SA187 protects Arabidopsis thaliana to heat stress. To understand the mechanisms at molecular level we performed RNA-seq