Project description:The effect of lanthanum concentration and the effect of different lanthanide elements on gene expression and growth was tested in P. alloputida KT2440. Gene expression analysis was based on high-throughput RNAseq starting from rRNA-depleted samples, followed by determining differentially expressed genes.
Project description:Pseudomonas alloputida KT2440 (previously misclassified as P. putida KT2440 based on 16S rRNA gene homology) has emerged as an ideal host strain for plan t biomass valorization. However, P. alloputida KT2440 is unable to natively utilize abundant pentose sugars (e.g., xylose and arabinose) in hydrolysate streams, which may account for up to 25% of lignocellulosic biomass. In the last decades, microbes have been engineered to utilize the pentose sugars. However, most of the engineered strains were either slow-growing or displayed phenotypes that could not be replicated. In this work, we successfully isolated five Pseudomonas species with the native capability to utilize glucose, xylose and p-coumarate as a sole carbon source. These isolates were in two clusters; one set of isolates (M2 and M5) and the second set of isolates (BP6 and BP7) showed 85.6% and 96.2% ANI, respectively, to P. alloputida KT24440. BP8 showed 84.6% ANI to P. putida KT2440 and does not belong to any neighboring type strains indicating a new species. Notably, the isolates showed robust growth solely on xylose and higher growth rates (m, 0.36-0.49 h-1) when compared to only known xylose-utilizing Pseudomonas taiwanenesis VLB120 (m, 0.28 h-1) as a control. Unexpectedly, among five isolates, M2 and M5 grew solely on arabinose as well. Comprehensive analysis of genomics, transcriptomics and proteomics revealed the isolates utilize xylose and arabinose via Weimberg pathway (xylD-xylX-xylA) and oxidative pathway (araD-araX-araA), respectively. Furthermore, a preliminary result demonstrated the production of flaviolin solely on xylose and arabinose in the isolate, showing noteworthy potential to be an alternative host for lignocellulosic feedstocks into valuable products. This is the first report on isolating Pseudomonas strains natively capable of utilizing all of the major carbon sources in lignocellulosic biomass, and leading to higher consumption of available substrates and therefore maximizing the product yield.
Project description:ErfA is a transcription factor of Pseudomonas aeruginosa. We here define the genome-wide binding sites of ErfA by DAP-seq in Pseudomonas aeruginosa PAO1 and IHMA87, Pseudomonas chlororaphis PA23, Pseudomonas protegens CHA0 and Pseudomonas putida KT2440.
Project description:A 4-nitrophenol-degrading bacterial strain PNP was isolated from pesticide-contaminated soil collected from Lucknow. Strain PNP utilized 0.5 mM 4-nitrophenol as its carbon source and degraded it completely within 24 h with stoichiometric release of nitrite ions. Strain PNP was associated with the genus Pseudomonas in a phylogentic tree and exhibited highest 16S rRNA gene sequence similarity to Pseudomonas juntendi BML3 (99.79%) and Pseudomonas inefficax JV551A3 (99.79%). Based on values of average nucleotide identity and digital DNA-DNA hybridization among strain PNP and its closely related type strains, it concluded that strain PNP belongs to Pseudomonas alloputida. The Illumina HiSeq platform was used to sequence the PNP genome. The draft genome sequence of Pseudomonas alloputida PNP was presented here. The total size of the draft assembly was 6,087,340 bp, distributed into 87 contigs with N50 value of 139502. The genome has an average GC content of 61.7% and contains 5461 coding sequences and 77 putative RNA genes. This Whole Genome Shotgun project has been submitted at DDBJ/ENA/GenBank under the accession JAGKJH000000000.
Project description:Different bacteria change their life styles in response to specific amino acids. In Pseudomonas putida (now alloputida) KT2440, arginine acts both as an environmental and a metabolic indicator that modulates the turnover of the intracellular second messenger c-di-GMP, and expression of biofilm-related genes. The transcriptional regulator ArgR, belonging to the AraC/XylS family, is key for the physiological reprogramming in response to arginine, as it controls transport and metabolism of the amino acid. To further expand our knowledge on the roles of ArgR, a global transcriptomic analysis of KT2440 and a null argR mutant growing in the presence of arginine was carried out. Results indicate that this transcriptional regulator influences a variety of cellular functions beyond arginine metabolism and transport, thus widening its regulatory role. ArgR acts as positive or negative modulator of the expression of several metabolic routes and transport systems, respiratory chain and stress response elements, as well as biofilm-related functions. The partial overlap between the ArgR regulon and those corresponding to the global regulators RoxR and ANR is also discussed.