C-di-GMP and biofilm are regulated in Pseudomonas putida by the CfcA/CfcR two-component system in response to salts.

In Pseudomonas putida KT2440, cfcR encodes an orphan multidomain response regulator with diguanylate cyclase activity, which is responsible for the synthesis of c-di-GMP, a second messenger key in the transition from planktonic to sessile bacterial lifestyles. When overexpressed, cfcR enhances biofilm formation and causes other phenotype alterations. The cfcA gene, encoding a membrane-anchored multisensory CHASE3/GAF hybrid histidine kinase (HK), is required to develop this pleiotropic phenotype.

Effluent decontamination by the ibuprofen-mineralizing strain, Sphingopyxis granuli RW412: Metabolic processes.

The high global consumption of ibuprofen and its limited elimination by wastewater treatment plants (WWTPs), has led to the contamination of aquatic systems by this common analgesic and its metabolites. The potentially negative environmental and public health effects of this emerging contaminant have raised concerns, driving the demand for treatment technologies. The implementation of bacteria which mineralize organic contaminants in biopurification systems used to decontaminate water or directly in processes in WWTPs, is a cheap and sustainable means for complete elimination before release into the environment.

Characterization of the bacteriocins and the PrtR regulator in a plant-associated Pseudomonas strain.

The emergence of antibiotic resistant bacterial strains demands the development of new antimicrobial agents. In the last decades, bacteriocins have gained significant interest due to their potential application as biopreservatives in the food industry and as therapeutic agents in medicine. Recent studies project the use of these antimicrobials in agriculture as biocontrol agents.

Draft Genome Sequences of Isolates from Sediments of the River Elbe That Are Highly Tolerant to Diclofenac.

Here, we report the genome sequences of one Achromobacter and four Pseudomonas strains isolated from sediments of the River Elbe which are highly tolerant toward the xenobiotic target compound diclofenac, a nonsteroidal anti-inflammatory drug (NSAID) and emerging contaminant.

Transcriptional response of Erwinia amylovora to copper shock: in vivo role of the copA gene.

Fire blight is a devastating plant disease caused by the bacterium Erwinia amylovora, and its control is frequently based on the use of copper-based compounds whose mechanisms of action are not well known. Consequently, in this article, we investigate the response of E. amylovora to copper shock by a whole-genome microarray approach.

Rhizosphere selection of Pseudomonas putida KT2440 variants with increased fitness associated to changes in gene expression.

As the interface between plant roots and soil, the rhizosphere is a complex environment where nutrients released by the plant promote microbial growth. Increasing evidences indicate that the plant also exerts a selective pressure on microbial populations in the rhizosphere, favouring colonization by certain groups. In this work, we have designed an experimental setup to begin analysing the evolution of a specific bacterial population in the rhizosphere, using Pseudomonas putida KT2440 as model organism.

Interplay between extracellular matrix components of Pseudomonas putida biofilms.

The extracellular matrix of bacterial biofilms has at least two key functions: to serve as a structural scaffold for the multicellular community, and to play a protective role against external stress. In this work, we report a compensatory effect whereby Pseudomonas putida reacts to the lack of either of the two main surface proteins involved in biofilm formation, LapA and LapF, by increasing expression and production of a species-specific EPS. Elevated levels of the second messenger molecule cyclic di-GMP alter the balance of extracellular matrix components, and the phenotypes of lapA and lapF mutants under these conditions are indicative of direct interactions taking place between large secreted proteins and exopolysaccharides.

Characterization of a phage-like pyocin from the plant growth-promoting rhizobacterium Pseudomonas fluorescens SF4c.

R-type and F-type pyocins are high-molecular-mass bacteriocins produced by Pseudomonas aeruginosa that resemble bacteriophage tails. They contain no head structures and no DNA, and are used as defence systems. In this report, we show that Pseudomonas fluorescens SF4c, a strain isolated from the wheat rhizosphere, produces a high-molecular-mass bacteriocin which inhibits the growth of closely related bacteria.