G Protein-Coupled Receptor 109A Maintains the Intestinal Integrity and Protects Against ETEC Mucosal Infection by Promoting IgA Secretion.

Several studies have reported an intricate link between the G protein-coupled receptor 109A (GPR109A) and intestinal health. Upon activation, induced by butyric acid and β-hydroxybutyric acid, GPR109A regulates the expression of tight junction proteins, exerts anti-inflammatory effects, and maintains the integrity of the intestinal barrier. However, its function and the mechanism of action in combating the infection caused by exogenous pathogenic microorganisms remain unclear.

Therapeutic applications of lytic phages in human medicine.

The emergence and spread of antibiotic-resistant bacteria constitute a critical issue for modern medicine. Patients with antibiotic-resistant bacterial infections consume more healthcare resources and have worse clinical outcomes than patients with antibiotic-sensitive bacterial infections. Phages are natural predators of bacteria and may therefore be a source of useful antibacterial drugs.

Overexpression of AmpC Promotes Bacteriophage Lysis of Ampicillin-Resistant .

Infections caused by antibiotic-resistant are a threat to human and animal health globally. Phage therapy has made great progress for the treatment of drug-resistant infections, but it is still unclear whether resistance to antibiotics could change the lysis ability of phages. In this study, we demonstrate that over expression of AmpC, an important β-lactamase for ampicillin resistance, promotes lysis of by phage utilizing OmpA as a receptor.

External lysis of Escherichia coli by a bacteriophage endolysin modified with hydrophobic amino acids.

Drug-resistant bacteria are a serious threat to global public health. Gram-positive bacterial endolysin preparations have been successfully used to fight Gram-positive bacteria as a novel antimicrobial replacement strategy. However, Gram-negative bacterial phage endolysins cannot be applied directly to destroy Gram-negative strains due to the externally inaccessible peptidoglycan layer of the cell wall; this has seriously hampered the development of endolysin-like antibiotics against Gram-negative bacteria.

A guard-killer phage cocktail effectively lyses the host and inhibits the development of phage-resistant strains of Escherichia coli.

In recent years, after the emergence of a large number of multidrug-resistant bacteria, phages and phage-associated products for the prevention and control of bacterial disease have revealed prominent advantages as compared with antibiotics. However, bacteria are susceptible to becoming phage-resistant, thus severely limiting the application of phage therapy. In this study, Escherichia coli cells were incubated with lytic bacteriophages to obtain mutants that were resistant to the lytic phages.

Corrigendum: Identification and Characterization of Dpo42, a Novel Depolymerase Derived from the Phage vB_EcoM_ECOO78.

[This corrects the article on p. 1460 in vol. 8, PMID: 28824588.

Identification and Characterization of Dpo42, a Novel Depolymerase Derived from the Phage vB_EcoM_ECOO78.

Biofilm formation, one of the most important virulence factors of pathogenic bacteria, protects bacteria against desiccation, antibiotics, phages and host immune responses. However, phage-derived depolymerases show antibiofilm activity and demonstrate great potential to treat infections caused by biofilm-forming bacteria. In this study, the phage vB_EcoM_ECOO78 was isolated and characterised, and we observed its ability to lyse five out of 34 tested clinical isolates.

The N-terminal and central domain of colicin A enables phage lysin to lyse Escherichia coli extracellularly.

Multidrug-resistant Escherichia coli has seriously threatened antibiotic resources and international public health. Bacteriophage lysin preparations have been widely considered as valid agents for solving multidrug resistances. Many lysins have been derived to treat diseases caused by Gram-positive bacteria, but only a few lysin preparations have been found that successively treat diseases caused by Gram-negative bacteria.

A safe and molecular-tagged Brucella canis ghosts confers protection against virulent challenge in mice.

Canine brucellosis, caused by Brucella canis, is a persistent infectious reproductive disease in dogs. The absence of effective treatment to the intracellular pathogen and the irreversible consequence of infection makes the need of a specific vaccine urgent. Bacterial ghosts (BGs) are the empty envelopes of bacteria with no genome content inside, which emerge as a proper vaccine candidate due to its intact outer antigen.

The antibacterial activity of E. coli bacteriophage lysin lysep3 is enhanced by fusing the Bacillus amyloliquefaciens bacteriophage endolysin binding domain D8 to the C-terminal region.

Bacteriophage endolysin is one of the most promising antibiotic substitutes, but in Gram-negative bacteria, the outer membrane prevents the lysin from hydrolyzing peptidoglycans and blocks the development of lysin applications. The prime strategy for new antibiotic substitutes is allowing lysin to access the peptidoglycan from outside of the bacteria by reformation of the lysin. In this study, the novel Escherichia coli (E.

Enhancement of the direct antimicrobial activity of Lysep3 against Escherichia coli by inserting cationic peptides into its C terminus.

Phage lysins are considered promising antimicrobials against resistant bacterial infections. Some lysins have been reported for the prevention and treatment of Gram-positive bacterial infection. Gram-negative bacterial phage lysins, however, can only destroy the bacterial cell wall from inside because of the obstruction of the bacterial outer membrane that prevents direct hydrolysis of the bacterial wall peptidoglycan from the outside, severely restricting the development of lysins against Gram-negative bacteria.

Genome sequencing and analysis of an Escherichia coli phage vB_EcoM-ep3 with a novel lysin, Lysep3.

Bacteriophages represent one prospect for preventing and treating multi-drug-resistant Escherichia coli. In this study, we have isolated a novel E. coli-specific bacteriophage and characterised its biological properties.

Effects of partial deletion of the wzm and wzt genes on lipopolysaccharide synthesis and virulence of Brucella abortus S19.

Brucellosis is a worldwide human and animal infectious disease, and the effective methods of its control are immunisation of animals by vaccination and elimination. Brucella abortus S19 is one of the popular vaccines with virulence in the control of cattle Brucellosis. In the present study, allelic exchange plasmids of wzm and wzt genes and partial knockout mutants of wzm and wzt were constructed to evaluate the resulting difference in virulence of B.

Immunogenic response induced by wzm and wzt gene deletion mutants from Brucella abortus S19.

Brucellosis is an infectious disease affecting humans and animals worldwide. Effective methods of control include inducing immunity in animals by vaccination and elimination. Brucella abortus S19 is one of the popular vaccines for control of cattle brucellosis, as it has low virulence.

A novel watery diarrhoea caused by the co-infection of neonatal piglets with Clostridium perfringens type A and Escherichia coli (K88, 987P).

In 2011, a novel watery diarrhoea in 1-7 day-old piglets occurred in Changchun, China, characterized by high pathogenicity and mortality. Investigation of clinical signs, examination for viruses, and isolation and identification of bacteria showed that co-infection by Clostridium perfringens type A and Escherichia coli (K88, 987P) was the most likely cause of the disease. Newborn piglets challenged with a mixture of Clostridium perfringens type A and Escherichia coli (K88, 987P) died within 3 days with clinical signs and gross lesions similar to those in the piglets that died in the outbreak.

Recombinant VirB5 protein as a potential serological marker for the diagnosis of bovine brucellosis.

The molecular tag vaccine against Brucella abortus and serological testing are the main methods of prevention of brucellosis used currently. They can discriminate vaccinated animals and humans from those naturally infected. In this study, we constructed a gene deletion mutant strain, B.