Quantification of serovar Typhimurium Population Dynamics in Murine Infection Using a Highly Diverse Barcoded Library.

Murine models are often used to study the pathogenicity and dissemination of the enteric pathogen serovar Typhimurium. Here, we quantified Typhimurium population dynamics in mice using the STAMPR analytic pipeline and a highly diverse . Typhimurium barcoded library containing 55,000 unique strains distinguishable by genomic barcodes by enumerating .

Inducible transposon mutagenesis for genome-scale forward genetics.

Transposon insertion sequencing (Tn-seq) is a powerful method for genome-scale functional genetics in bacteria. However, its effectiveness is often limited by a lack of mutant diversity, caused by either inefficient transposon delivery or stochastic loss of mutants due to population bottlenecks. Here, we introduce "InducTn-seq", which leverages inducible mutagenesis for temporal control of transposition.

Phage-Related Ribosomal Proteases (Prps): Discovery, Bioinformatics, and Structural Analysis.

Many new antimicrobials are analogs of existing drugs, sharing the same targets and mechanisms of action. New antibiotic targets are critically needed to combat the growing threat of antimicrobial-resistant bacteria. Phage-related ribosomal proteases (Prps) are a recently structurally characterized antibiotic target found in pathogens such as , , and These bacteria encode an N-terminal extension on their ribosomal protein L27 that is not present in other bacteria.

Phage-Related Ribosomal Protease (Prp) of : In Vitro Michaelis-Menten Kinetics, Screening for Inhibitors, and Crystal Structure of a Covalent Inhibition Product Complex.

Phage-related ribosomal proteases (Prps) are essential for the assembly and maturation of the ribosome in Firmicutes, including the human pathogens , , and . These bacterial proteases cleave off an N-terminal extension of a precursor of ribosomal protein L27, a processing step that is essential for the formation of functional ribosomes. This essential role of Prp in these pathogens has identified this protease as a potential antibiotic target.

The Case against Antibiotics and for Anti-Virulence Therapeutics.

Although antibiotics have been indispensable in the advancement of modern medicine, there are downsides to their use. Growing resistance to broad-spectrum antibiotics is leading to an epidemic of infections untreatable by first-line therapies. Resistance is exacerbated by antibiotics used as growth factors in livestock, over-prescribing by doctors, and poor treatment adherence by patients.

Molecular Targets and Strategies for Inhibition of the Bacterial Type III Secretion System (T3SS); Inhibitors Directly Binding to T3SS Components.

The type III secretion system (T3SS) is a virulence apparatus used by many Gram-negative pathogenic bacteria to cause infections. Pathogens utilizing a T3SS are responsible for millions of infections yearly. Since many T3SS knockout strains are incapable of causing systemic infection, the T3SS has emerged as an attractive anti-virulence target for therapeutic design.

Fluorescence Detection of Type III Secretion Using a Glu-CyFur Reporter System in .

Enteropathogenic (EPEC) is a major cause of infantile diarrhea worldwide. EPEC and the closely related murine model of EPEC infection, , utilize a type III secretion system (T3SS) to propagate the infection. Since the T3SS is not essential for the bacteria to survive or propagate, inhibiting the virulence factor with a therapeutic would treat the infection without causing harm to commensal bacteria.

Antibodies Inhibiting the Type III Secretion System of Gram-Negative Pathogenic Bacteria.

Pathogenic bacteria are a global health threat, with over 2 million infections caused by Gram-negative bacteria every year in the United States. This problem is exacerbated by the increase in resistance to common antibiotics that are routinely used to treat these infections, creating an urgent need for innovative ways to treat and prevent virulence caused by these pathogens. Many Gram-negative pathogenic bacteria use a type III secretion system (T3SS) to inject toxins and other effector proteins directly into host cells.

Animal Models of Type III Secretion System-Mediated Pathogenesis.

The type III secretion system (T3SS) is a conserved virulence factor used by many Gram-negative pathogenic bacteria and has become an important target for anti-virulence drugs. Most T3SS inhibitors to date have been discovered using in vitro screening assays. Pharmacokinetics and other important characteristics of pharmaceuticals cannot be determined with in vitro assays alone.