Carbapenem-resistant Acinetobacter baumannii (CRAB): metabolic adaptation and transcriptional response to human urine (HU).

Carbapenem-resistant Acinetobacter baumannii (CRAB) is a major human pathogen and a research priority for developing new antimicrobial agents. CRAB is a causative agent of a variety of infections in different body sites. One of the manifestations is catheter-associated urinary tract infection, which exposes the bacteria to the host's urine, creating a particular environment.

Lacticaseibacillus rhamnosus CRL 2244 secreted metabolites display killing and antibiotic synergistic activity against multi-drug resistant pathogens.

A growing increase in the number of serious infections caused by multidrug resistant bacteria (MDR) is challenging our society. Despite efforts to discover novel therapeutic options, few antibiotics targeting MDR have been approved by the Food and Drug Administration (FDA). Lactic acid bacteria have emerged as a promising therapeutic alternative due to their demonstrated ability to combat MDR pathogens in vitro.

Carbapenem-resistant Acinetobacter baumannii (CRAB): metabolic adaptation and transcriptional response to human urine (HU).

Carbapenem-resistant (CRAB) is a major human pathogen and a research priority for developing new antimicrobial agents. CRAB is a causative agent of a variety of infections in different body sites. One of the manifestations is catheter-associated urinary tract infection, which exposes the bacteria to the host's urine, creating a particular environment.

Antimicrobial activity of the Lacticaseibacillus rhamnosus CRL 2244 and its impact on the phenotypic and transcriptional responses in carbapenem resistant Acinetobacter baumannii.

Carbapenem-resistant Acinetobacter baumannii (CRAB) is a recognized nosocomial pathogen with limited antibiotic treatment options. Lactic acid bacteria (LAB) constitute a promising therapeutic alternative. Here we studied the antibacterial properties of a collection of LAB strains using phenotypic and transcriptomic analysis against A.

Induced Heteroresistance in Carbapenem-Resistant (CRAB) via Exposure to Human Pleural Fluid (HPF) and Its Impact on Cefiderocol Susceptibility.

Infections caused by Carbapenem-resistant (CRAB) isolates, such as hospital-acquired pneumonia (HAP), bacteremia, and skin and soft tissue infections, among others, are particularly challenging to treat. Cefiderocol, a chlorocatechol-substituted siderophore antibiotic, was approved by the U.S.

Phenotypic and transcriptional analysis of the antimicrobial effect of lactic acid bacteria on carbapenem-resistant Acinetobacter baumannii: Lacticaseibacillus rhamnosus CRL 2244 an alternative strategy to overcome resistance?".

Carbapenem-resistant (CRAB) is a recognized nosocomial pathogen with limited antibiotic treatment options. Lactic acid bacteria (LAB) constitute a promising therapeutic alternative. Here we studied the antibacterial properties of a collection of LAB strains using phenotypic and transcriptomic analysis against clinical strains.

Genomic Comparative Analysis of Two Multi-Drug Resistance (MDR) Clinical Strains Assigned to International Clonal Lineage II Recovered Pre- and Post-COVID-19 Pandemic.

Background: After the emergence of COVID-19, numerous cases of /SARS-CoV-2 co-infection were reported. Whether the co-infecting strains have distinctive characteristics remains unknown.

Methods And Results: AMA_NO was isolated in 2021 from a patient with COVID-19.

The Iron Content of Human Serum Albumin Modulates the Susceptibility of to Cefiderocol.

The mortality rates of patients infected with who were treated with cefiderocol (CFDC) were not as favorable as those receiving the best available treatment for pulmonary and bloodstream infections. Previous studies showed that the presence of human serum albumin (HSA) or HSA-containing fluids, such as human serum (HS) or human pleural fluid (HPF), in the growth medium is correlated with a decrease in the expression of genes associated with high-affinity siderophore-mediated iron uptake systems. These observations may explain the complexities of the observed clinical performance of CFDC in pulmonary and bloodstream infections, because ferric siderophore transporters enhance the penetration of CFDC into the bacterial cell.

Human serum albumin (HSA) regulates the expression of histone-like nucleoid structure protein (H-NS) in Acinetobacter baumannii.

According to the Centers for Disease Control and Prevention, Acinetobacter baumannii is listed among the most threatening pathogens. A. baumannii is mainly a nosocomial pathogen with a distinctive ability to survive in multiple environments.

Acinetobacter baumannii response to cefiderocol challenge in human urine.

Cefiderocol (CFDC) is a novel chlorocatechol-substituted siderophore antibiotic approved to treat complicated urinary tract infections (cUTI) and hospital-acquired and ventilator-acquired pneumonia (HAP/VAP). Previous work determined that albumin-rich human fluids increase the minimum inhibitory concentration (MICs) of Acinetobacter baumannii against CFDC and reduce the expression of genes related to iron uptake systems. This latter effect may contribute to the need for higher concentrations of CFDC to inhibit growth.

α-Toxin Effect on Behavior.

Polymicrobial infections are more challenging to treat and are recognized as responsible for significant morbidity and mortality. It has been demonstrated that multiple Gram-negative organisms take advantage of the effects of α-toxin on mucosal host defense, resulting in proliferation and dissemination of the co-infecting pathogens. Through phenotypic approaches, we observed a decrease in the motility of A118 after exposure to cell-free conditioned media (CFCM) of strains, USA300 and LS1.

Human Serum Proteins and Susceptibility of to Cefiderocol: Role of Iron Transport.

Cefiderocol, a recently introduced antibiotic, has a chemical structure that includes a cephalosporin that targets cell wall synthesis and a chlorocatechol siderophore moiety that facilitates cell penetration by active iron transporters. Analysis of the effect that human serum, human serum albumin, and human pleural fluid had on growing showed that genes related to iron uptake were down-regulated. At the same time, β-lactamase genes were expressed at higher levels.

Involvement of the Histone-Like Nucleoid Structuring Protein (H-NS) in Natural Transformation.

Most strains are naturally competent. Although some information is available about factors that enhance or reduce the frequency of the transformation of this bacterium, the regulatory elements and mechanisms are barely understood. In this article, we describe studies on the role of the histone-like nucleoid structuring protein, H-NS, in the regulation of the expression of genes related to natural competency and the ability to uptake foreign DNA.

Histone-like nucleoid-structuring protein (H-NS) regulatory role in antibiotic resistance in Acinetobacter baumannii.

In the multidrug resistant (MDR) pathogen Acinetobacter baumannii the global repressor H-NS was shown to modulate the expression of genes involved in pathogenesis and stress response. In addition, H-NS inactivation results in an increased resistance to colistin, and in a hypermotile phenotype an altered stress response. To further contribute to the knowledge of this key transcriptional regulator in A.

Effect of Serum Albumin, a Component of Human Pleural Fluid, on Transcriptional and Phenotypic Changes on Acinetobacter baumannii A118.

Acinetobacter baumannii is a multidrug-resistant pathogen that causes numerous infections associated with high mortality rates. Exposure to human body fluids, such as human pleural fluid (HPF) and human serum, modulates gene expression in A. baumannii, leading to changes in its pathogenic behavior.

Interaction of with Human Serum Albumin: Does the Host Determine the Outcome?

has become a serious threat to human health due to its extreme antibiotic resistance, environmental persistence, and capacity to survive within the host. Two strains, A118 and AB5075, commonly used as model systems, and three carbapenem-resistant strains, which are becoming ever more dangerous due to the multiple drugs they can resist, were exposed to 3.5% human serum albumin (HSA) and human serum (HS) to evaluate their response with respect to antimicrobial resistance, biofilm formation, and quorum sensing, all features responsible for increasing survival and persistence in the environment and human body.

Interplay between Meropenem and Human Serum Albumin on Expression of Carbapenem Resistance Genes and Natural Competence in Acinetobacter baumannii.

Acinetobacter baumannii A118, a carbapenem-susceptible strain, and AB5075, carbapenem resistant, were cultured in lysogeny broth (LB) or LB with different supplements, such as 3.5% human serum albumin (HSA), human serum (HS), meropenem, or meropenem plus 3.5% HSA.

Human Pleural Fluid and Human Serum Albumin Modulate the Behavior of a Hypervirulent and Multidrug-Resistant (MDR) Representative Strain.

is a nosocomial pathogen capable of causing serious infections associated with high rates of morbidity and mortality. Due to its antimicrobial drug resistance profile, is categorized as an urgent priority pathogen by the Centers for Disease Control and Prevention in the United States and a priority group 1 critical microorganism by the World Health Organization. Understanding how adapts to different host environments may provide critical insights into strategically targeting this pathogen with novel antimicrobial and biological therapeutics.

Action of Colloidal Bismuth Hydroxide Gel and its Commercial Cream on Enteropathogens and Colonizers of the Gastrointestinal Tract.

Background: Acute diarrheal diseases constitute a world public health problem because they are the second cause of death in children under 5 years of age. Colloidal bismuth hydroxide gel (CBHG) is an active ingredient in low-cost, antidiarrhetic drugs for oral use; it does not inhibit intestinal motility, and it features very low intestinal absorption of <1%.

Materials And Methods: We analyzed the sensitivity by determining the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC); the effect on bacterial growth by studying the specific growth velocity and the generation time in growth curves; and bacterial attachment by counting viable plaques, of enteropathogenic , shigatoxigenic O157:H7, , spp.

The inhibitory effect of colloidal bismuth hydroxide gel on Escherichia coli O157:H7 and on the activity of Shiga toxins.

Background: Shiga toxin-producing Escherichia coli (STEC) is the causative agent of hemolytic uremic syndrome (HUS). Colloidal bismuth hydroxide gel (CBHG) is an anti-diarrheal and antisecretory compound, which does not inhibit gastrointestinal motility and reaches an in vivo gut concentration of 10.8 mg/ml of bismuth.

Effect of preservatives on Shiga toxigenic phages and Shiga toxin of Escherichia coli O157:H7.

Toxin synthesis by Shiga toxin-producing Escherichia coli (STEC) appears to be coregulated through the induction of the integrated bacteriophages that encode the toxin genes. These phages might be the principal means for the dissemination and release of Shiga toxins. We evaluated the effect of three common food preservatives, potassium sorbate, sodium benzoate, and sodium propionate, on the propagation of the phages and Shiga toxins.