17 research outputs found
Adaptive remodeling of the bacterial proteome by specific ribosomal modification regulates Pseudomonas infection and niche colonisation
Post-transcriptional control of protein abundance is a highly important, underexplored regulatory process by which organisms respond to their environments. Here we describe an important and previously unidentified regulatory pathway involving the ribosomal modification protein RimK, its regulator proteins RimA and RimB, and the widespread bacterial second messenger cyclic-di-GMP (cdG). Disruption of rimK affects motility and surface attachment in pathogenic and commensal Pseudomonas species, with rimK deletion significantly compromising rhizosphere colonisation by the commensal soil bacterium P. fluorescens, and plant infection by the pathogens P. syringae and P. aeruginosa. RimK functions as an ATP-dependent glutamyl ligase, adding glutamate residues to the C-terminus of ribosomal protein RpsF and inducing specific effects on both ribosome protein complement and function. Deletion of rimK in P. fluorescens leads to markedly reduced levels of multiple ribosomal proteins, and also of the key translational regulator Hfq. In turn, reduced Hfq levels induce specific downstream proteomic changes, with significant increases in multiple ABC transporters, stress response proteins and non-ribosomal peptide synthetases seen for both ÎrimK and Îhfq mutants. The activity of RimK is itself controlled by interactions with RimA, RimB and cdG. We propose that control of RimK activity represents a novel regulatory mechanism that dynamically influences interactions between bacteria and their hosts; translating environmental pressures into dynamic ribosomal changes, and consequently to an adaptive remodeling of the bacterial proteome
Analysis of the genomic sequences and metabolites of Serratia surfactantfaciens sp. nov. YD25T that simultaneously produces prodigiosin and serrawettin W2
Symbiosis, virulence and natural-product biosynthesis in entomopathogenic bacteria are regulated by a small RNA
Testing for the Effects and Consequences of Mid Paleogene Climate Change on Insect Herbivory
Utilization of ultrasonography to detect developmental dysplasia of the hip: when reality turns selective screening into universal use
A Serratia marcescens PigP Homolog Controls Prodigiosin Biosynthesis, Swarming Motility and Hemolysis and Is Regulated by cAMP-CRP and HexS
The PaleoceneâEocene Thermal Maximum: Plants as Paleothermometers, Rain Gauges, and Monitors
We travel back in time through this chapter and take a field trip to western North America during the Paleoceneâ Eocene Thermal Maximum (PETM), some 56 million years ago. Here, plant-and-animal fossils were discovered in the warmest interval of the last 500 million years, a condition that lasted only 200,000 years. We provide a brief review of what may have caused a massive influx of atmospheric carbon detected during the PETM. We contrast the PETM to similar ongoing thermal events that began during the Industrial Revolution and persist today. We discuss the tools that paleobotanists have devised to interpret climate from fossil leaf, pollen, and wood records and present a brief overview of floral changes that occurred in western North America before, during, and right after this thermal maximum. Lastly, we explore how fossil data can be incorporated with ecological and systematic information into biogeographical models to predict how Cenozoic plants respond to climate change