A Broad Spectrum Lasso Peptide Antibiotic Targeting the Bacterial Ribosome.

Lasso peptides, biologically active molecules with a distinct structurally constrained knotted fold, are natural products belonging to the class of ribosomally-synthesized and posttranslationally modified peptides (RiPPs). Lasso peptides act upon several bacterial targets, but none have been reported to inhibit the ribosome, one of the main antibiotic targets in the bacterial cell. Here, we report the identification and characterization of the lasso peptide antibiotic, lariocidin (LAR), and its internally cyclized derivative, lariocidin B (LAR-B), produced by .

A GMMA-CPS-Based Vaccine for Non-Typhoidal .

Non-typhoidal are a major cause of gastroenteritis worldwide, as well as causing bloodstream infections in sub-Saharan Africa with a high fatality rate. No vaccine is currently available for human use. Current vaccine development strategies are focused on capsular polysaccharides (CPS) present on the surface of non-typhoidal .

A SNP in the Cache 1 Signaling Domain of Diguanylate Cyclase STM1987 Leads to Increased Fitness of Invasive Strains.

Nontyphoidal (NTS) strains are associated with gastroenteritis worldwide but are also the leading cause of bacterial bloodstream infections in sub-Saharan Africa. The invasive NTS (iNTS) strains that cause bloodstream infections differ from standard gastroenteritis-causing strains by >700 single-nucleotide polymorphisms (SNPs). These SNPs are known to alter metabolic pathways and biofilm formation and to contribute to serum resistance and are thought to signify iNTS strains becoming human adapted, similar to typhoid fever-causing strains.

In vivo synthesis of bacterial amyloid curli contributes to joint inflammation during S. Typhimurium infection.

Reactive arthritis, an autoimmune disorder, occurs following gastrointestinal infection with invasive enteric pathogens, such as Salmonella enterica. Curli, an extracellular, bacterial amyloid with cross beta-sheet structure can trigger inflammatory responses by stimulating pattern recognition receptors. Here we show that S.

Metabolic Activation of CsgD in the Regulation of Biofilms.

Among human food-borne pathogens, gastroenteritis-causing strains have the most real-world impact. Like all pathogens, their success relies on efficient transmission. Biofilm formation, a specialized physiology characterized by multicellular aggregation and persistence, is proposed to play an important role in the transmission cycle.

Kinetic and structural analysis of Escherichia coli phosphoenolpyruvate carboxykinase mutants.

Background: Phosphoenolpyruvate carboxykinase (PEPCK) is a metabolic enzyme in the gluconeogenesis pathway, where it catalyzes the reversible conversion of oxaloacetate (OAA) to phosphoenolpyruvate (PEP) and CO. The substrates for Escherichia coli PEPCK are OAA and MgATP, with Mn acting as a cofactor. Analysis of PEPCK structures have revealed amino acid residues involved in substrate/cofactor coordination during catalysis.

One-step amino acid selective isotope labeling of proteins in prototrophic Escherichia coli strains.

Amino acid selective isotope labeling is a useful approach to simplification of nuclear magnetic resonance (NMR) spectra of large proteins. Cell-free protein synthesis offers essentially unlimited flexibility of labeling patterns but is labor-intensive and expensive. In vivo labeling is simple in principle but generally requires auxotrophic strains, inhibitors of amino acid synthesis, or complex media formulations.