Marek Basler

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Type VI secretion systems are bacterial virulence-associated nanomachines composed of proteins that are evolutionarily related to components of bacteriophage tails. Here we show that protein secretion by the type VI secretion system of Vibrio cholerae requires the action of a dynamic intracellular tubular structure that is structurally and functionally(More)
Protein secretion is a common property of pathogenic microbes. Gram-negative bacterial pathogens use at least 6 distinct extracellular protein secretion systems to export proteins through their multilayered cell envelope and in some cases into host cells. Among the most widespread is the newly recognized Type VI secretion system (T6SS) which is composed of(More)
The bacterial type VI secretion system (T6SS) is a dynamic organelle that bacteria use to target prey cells for inhibition via translocation of effector proteins. Time-lapse fluorescence microscopy has documented striking dynamics of opposed T6SS organelles in adjacent sister cells of Pseudomonas aeruginosa. Such cell-cell interactions have been termed(More)
The bacterial type 6 secretion system (T6SS) functions as a virulence factor capable of attacking both eukaryotic and prokaryotic target cells by a process that involves protein transport through a contractile bacteriophage tail-like structure. The T6SS apparatus is composed, in part, of an exterior sheath wrapped around an interior tube. Here, we report(More)
Repeats-in-toxin (RTX) exoproteins of Gram-negative bacteria form a steadily growing family of proteins with diverse biological functions. Their common feature is the unique mode of export across the bacterial envelope via the type I secretion system and the characteristic, typically nonapeptide, glycine- and aspartate-rich repeats binding Ca(2+) ions. In(More)
The bacterial type VI secretion system (T6SS) is a large multicomponent, dynamic macromolecular machine that has an important role in the ecology of many Gram-negative bacteria. T6SS is responsible for translocation of a wide range of toxic effector molecules, allowing predatory cells to kill both prokaryotic as well as eukaryotic prey cells. The T6SS(More)
Gram-negative bacteria use the type VI secretion system (T6SS) to translocate toxic effector proteins into adjacent cells. The Pseudomonas aeruginosa H1-locus T6SS assembles in response to exogenous T6SS attack by other bacteria. We found that this lethal T6SS counterattack also occurs in response to the mating pair formation (Mpf) system encoded by(More)
Signal transduction pathways in both prokaryotes and eukaryotes utilize protein phosphorylation as a key regulatory mechanism. Recent studies have proven that eukaryotic-type serine/threonine protein kinases (Hank's type) are widespread in many bacteria, although little is known regarding the cellular processes they control. In this study, we have attempted(More)
The first systematic study of small non-coding RNAs (sRNA, ncRNA) in Streptomyces is presented. Except for a few exceptions, the Streptomyces sRNAs, as well as the sRNAs in other genera of the Actinomyces group, have remained unstudied. This study was based on sequence conservation in intergenic regions of Streptomyces, localization of transcription(More)
Bordetella adenylate cyclase toxin-hemolysin (CyaA, AC-Hly, or ACT) permeabilizes cell membranes by forming small cation-selective (hemolytic) pores and subverts cellular signaling by delivering into host cells an adenylate cyclase (AC) enzyme that converts ATP to cAMP. Both AC delivery and pore formation were previously shown to involve a predicted(More)