Protoplast fusion in Bacillus species produces frequent, unbiased, genome-wide homologous recombination.

In eukaryotes, fine-scale maps of meiotic recombination events have greatly advanced our understanding of the factors that affect genomic variation patterns and evolution of traits. However, in bacteria that lack natural systems for sexual reproduction, unbiased characterization of recombination landscapes has remained challenging due to variable rates of genetic exchange and influence of natural selection. Here, to overcome these limitations and to gain a genome-wide view on recombination, we crossed Bacillus strains with different genetic distances using protoplast fusion.

Proteome and acylome analyses of the functional interaction network between the carbazole-degradative plasmid pCAR1 and host Pseudomonas putida KT2440.

Understanding the interplay between a plasmid and its host system is a bottleneck towards prediction of the fate of plasmid-harbouring strains in the natural environments. Here, we studied the impact of the conjugative plasmid pCAR1, involved in carbazole degradation, on the proteome of Pseudomonas putida KT2440 using SILAC method. Furthermore, we investigated two acyl lysine modifications (acetylation and succinylation) that respond to the metabolic status of the cell and are implicated in regulation of various cellular processes.

Growth phase-dependent expression profiles of three vital H-NS family proteins encoded on the chromosome of Pseudomonas putida KT2440 and on the pCAR1 plasmid.

Background: H-NS family proteins are nucleoid-associated proteins that form oligomers on DNA and function as global regulators. They are found in both bacterial chromosomes and plasmids, and were suggested to be candidate effectors of the interaction between them. TurA and TurB are the predominantly expressed H-NS family proteins encoded on the chromosome of Pseudomonas putida KT2440, while Pmr is encoded on the carbazole-degradative incompatibility group P-7 plasmid pCAR1.

Structural similarities and differences in H-NS family proteins revealed by the N-terminal structure of TurB in Pseudomonas putida KT2440.

H-NS family proteins play key roles in bacterial nucleoid compaction and global transcription. MvaT homologues in Pseudomonas have almost negligible amino acid sequence identity with H-NS, but can complement an hns-related phenotype of Escherichia coli. Here, we report the crystal structure of the N-terminal dimerization/oligomerization domain of TurB, an MvaT homologue in Pseudomonas putida KT2440.

Effects of three different nucleoid-associated proteins encoded on IncP-7 plasmid pCAR1 on host Pseudomonas putida KT2440.

Nucleoid-associated proteins (NAPs), which fold bacterial DNA and influence gene transcription, are considered to be global transcriptional regulators of genes on both plasmids and the host chromosome. Incompatibility P-7 group plasmid pCAR1 carries genes encoding three NAPs: H-NS family protein Pmr, NdpA-like protein Pnd, and HU-like protein Phu. In this study, the effects of single or double disruption of pmr, pnd, and phu were assessed in host Pseudomonas putida KT2440.

Effect of iron limitation and fur gene inactivation on the transcriptional profile of the strict anaerobe Clostridium acetobutylicum.

Iron is a nutrient of critical importance for the strict anaerobe Clostridium acetobutylicum, as it is involved in numerous basic cellular functions and metabolic pathways. A gene encoding a putative ferric uptake regulator (Fur) has been identified in the genome of C. acetobutylicum.