Anti-Virulence Properties of Plant Species: Correlation between In Vitro Activity and Efficacy in a Murine Model of Bacterial Infection.

Several plant extracts exhibit anti-virulence properties due to the interruption of bacterial quorum sensing (QS). However, studies on their effects at the preclinical level are scarce. Here, we used a murine model of abscess/necrosis induced by to evaluate the anti-pathogenic efficacy of 24 plant extracts at a sub-inhibitory concentration.

CesL Regulates Type III Secretion Substrate Specificity of the Enteropathogenic Injectisome.

The type III secretion system (T3SS) is a complex molecular device used by several pathogenic bacteria to translocate effector proteins directly into eukaryotic host cells. One remarkable feature of the T3SS is its ability to secrete different categories of proteins in a hierarchical manner, to ensure proper assembly and timely delivery of effectors into target cells. In enteropathogenic , the substrate specificity switch from translocator to effector secretion is regulated by a gatekeeper complex composed of SepL, SepD, and CesL proteins.

Novel insights into the mechanism of SepL-mediated control of effector secretion in enteropathogenic Escherichia coli.

Type three secretion systems (T3SSs) are virulence determinants employed by several pathogenic bacteria as molecular syringes to inject effector proteins into host cells. Diarrhea-producing enteropathogenic Escherichia coli (EPEC) uses a T3SS to colonize the intestinal tract. T3S is a highly coordinated process that ensures hierarchical delivery of three classes of substrates: early (inner rod and needle subunits), middle (translocators), and late (effectors).

Functional Characterization of EscK (Orf4), a Sorting Platform Component of the Enteropathogenic Escherichia coli Injectisome.

Unlabelled: The type III secretion system (T3SS) is a supramolecular machine used by many bacterial pathogens to translocate effector proteins directly into the eukaryotic host cell cytoplasm. Enteropathogenic Escherichia coli (EPEC) is an important cause of infantile diarrheal disease in underdeveloped countries. EPEC virulence relies on a T3SS encoded within a chromosomal pathogenicity island known as the locus of enterocyte effacement (LEE).

Characterization of Escherichia coli Isolates from an Urban Lake Receiving Water from a Wastewater Treatment Plant in Mexico City: Fecal Pollution and Antibiotic Resistance.

The presence of enteric bacteria in water bodies is a cause of public health concerns, either by directly causing water- and food-borne diseases, or acting as reservoirs for antibiotic resistance determinants. Water is used for crop irrigation; and sediments and aquatic plants are used as fertilizing supplements and soil conditioners. In this work, the bacterial load of several micro-environments of the urban lake of Xochimilco, in Mexico City, was characterized.

EscO, a functional and structural analog of the flagellar FliJ protein, is a positive regulator of EscN ATPase activity of the enteropathogenic Escherichia coli injectisome.

Type III secretion systems (T3SSs) are multiprotein molecular devices used by many Gram-negative bacterial pathogens to translocate effector proteins into eukaryotic cells. A T3SS is also used for protein export in flagellar assembly, which promotes bacterial motility. The two systems are evolutionarily related, possessing highly conserved components in their export apparatuses.

Flagella from five Cronobacter species induce pro-inflammatory cytokines in macrophage derivatives from human monocytes.

Cronobacter spp. are opportunistic pathogens linked to lie-threatening infections in neonates and contaminated powdered infant formula that has been epidemiologically associated with these cases. Clinical symptoms of Cronobacter include necrotizing enterocolitis, bacteremia, and meningitis.

Role of EscP (Orf16) in injectisome biogenesis and regulation of type III protein secretion in enteropathogenic Escherichia coli.

Enteropathogenic Escherichia coli employs a type III secretion system (T3SS) to translocate virulence effector proteins directly into enterocyte host cells, leading to diarrheal disease. The T3SS is encoded within the chromosomal locus of enterocyte effacement (LEE). The function of some of the LEE-encoded proteins remains unknown.

The muramidase EtgA from enteropathogenic Escherichia coli is required for efficient type III secretion.

Enteropathogenic Escherichia coli (EPEC) is an important cause of infectious diarrhoea. It colonizes human intestinal epithelial cells by delivering effector proteins into the host cell cytoplasm via a type III secretion system (T3SS) encoded within the chromosomal locus of enterocyte effacement (LEE). The LEE pathogenicity island also encodes a lytic transglycosylase (LT) homologue named EtgA.

Enzymatic characterization of the enteropathogenic Escherichia coli type III secretion ATPase EscN.

Type III secretion is a transport mechanism by which bacteria secrete proteins across their cell envelope. This protein export pathway is used by two different bacterial nanomachines: the flagellum and the injectisome. An indispensable component of these secretion systems is an ATPase similar to the F1-ATPase beta subunit.

Trypanosoma cruzi ribosomal protein S4: characterization of its coding locus, analysis of transcripts, and antigenicity of the protein.

Two allelic genomic fragments containing ribosomal protein S4 encoding genes (rpS4) from Trypanosoma cruzi (CL-Brener strain) were isolated and characterized. One allele comprises two complete tandem repeats of a sequence encoding an rpS4 gene. In the other, only one rpS4 gene is found.

The stabilization of housekeeping transcripts in Trypanosoma cruzi epimastigotes evidences a global regulation of RNA decay during stationary phase.

The relative steady state concentration of mRNAs of four housekeeping single-copy type Trypanosoma cruzi genes (actin, triosephosphate isomerase, trypanothion reductase and the ribosomal protein S4) was analyzed throughout the growth curve. A distinguishable pattern was observed with maximal levels occurring at the logarithmic phase of growth and minimum levels occurring at the stationary phase. The half-lives of all analyzed messenger RNAs, and also of three molecular species of immature ribosomal RNAs were increased in cells isolated from stationary phase.

Trypanosoma cruzi: allelic comparisons of the actin genes and analysis of their transcripts.

Two allelic genomic fragments containing actin genes from Trypanosoma cruzi were isolated and characterized. One allele comprises two complete tandem repeats of a sequence encoding an actin gene. In the other, only one actin gene is found.

Separable putative polyadenylation and cleavage motifs in Trichomonas vaginalis mRNAs.

3' Untranslated region processing and polyadenylation in Trichomonas vaginalis was analyzed by 3' rapid amplification of cDNA ends and sequence analysis of T. vaginalis mRNAs. A putative polyadenylation signal with the sequence UAAA was found 11-30 nucleotides upstream from the cleavage site.