Benzoic acid derivatives as potent antibiofilm agents against Klebsiella pneumoniae biofilm

Relationship between biofilm formation and antibiotic resistance of Klebsiella pneumoniae and updates on antibiofilm therapeutic strategies

Klebsiella pneumoniae is a Gram-negative bacterium within the Enterobacteriaceae family that can cause multiple systemic infections, such as respiratory, blood, liver abscesses and urinary systems. Antibiotic resistance is a global health threat and K. pneumoniae warrants special attention due to its resistance to most modern day antibiotics. Biofilm formation is a critical obstruction that enhances the antibiotic resistance of K. pneumoniae. However, knowledge on the molecular mechanisms of biofilm formation and its relation with antibiotic resistance in K. pneumoniae is limited. Understanding the molecular mechanisms of biofilm formation and its correlation with antibiotic resistance is crucial for providing insight for the design of new drugs to control and treat biofilm-related infections. In this review, we summarize recent advances in genes contributing to the biofilm formation of K. pneumoniae, new progress on the relationship between biofilm formation and antibiotic resistance, and new therapeutic strategies targeting biofilms. Finally, we discuss future research directions that target biofilm formation and antibiotic resistance of this priority pathogen.

Interrogating Salmonella Typhi biofilm formation and dynamics to understand antimicrobial resistance

AIMS

Salmonella Typhi biofilm-mediated infections are globally rising. Due to the emergence of drug resistance antibiotics did not show effective results against S. Typhi biofilm. Therefore, there is an urgent need for an in-depth interrogation of S. Typhi biofilm to understand its formation kinetics, compositions, and surface charge value.

METHODS

This study utilized the S. Typhi MTCC-733 strain from a microbial-type culture collection in India. The S. Typhi biofilm was formed on a glass slide in a biofilm development apparatus. Typhoidal biofilm analysis was done with the help of various assays such as a crystal violet assay, SEM analysis, FTIR analysis, Raman analysis, and zeta potential analysis.

KEY FINDING

This article contained a comprehensive assessment of the typhoid biofilm formation kinetics, biofilm compositions, and surface charge which revealed that cellulose was a major molecule in the typhoidal biofilm which can be used as a major biofilm drug target against typhoidal biofilm.

SIGNIFICANCE

This study provided interrogations about typhoidal biofilm kinetics which provided ideas about the biofilm composition. The cellulose molecule showed a major component of S. Typhi biofilm and it could potentially involved in drug resistance, and offer a promising avenue for developing a new antibiofilm therapeutic target to conquer the big obstacle of drug resistance. The obtained information can be instrumental in designing novel therapeutic molecules in the future to combat typhoidal biofilm conditions effectively for overcoming antibiotic resistance against bacterial infection Salmonella.

Benzoic acid supplementation improves the growth performance, nutrient digestibility and nitrogen metabolism of weaned lambs

Nitrogen is one of the essential components of proteins and nucleic acids and plays a crucial role in the growth and development of ruminants. However, the nitrogen utilization rate of ruminants is lower than that of monogastric animals, which not only reduces protein conversion and utilization, but also increases manure nitrogen discharge as well as causing environmental pollution. The lamb stage is an important period in the life of sheep, which can affect the production performance and meat quality of fattening sheep. The purpose of this experiment was to explore effects of benzoic acid supplementation on growth performance, nutrient digestibility, nitrogen metabolism and plasma parameters of weaned lambs. A total of 40 weaned male Hu sheep lambs with similar body weight were randomly divided into 4 groups: control with no benzoic acid (0 BA) and the lambs in other 3 groups were fed 0.5, 1, and 1.5% benzoic acid on the basis of experimental diet (0.5, 1, and 1.5 BA, respectively). The experiment lasted for 60 days. Results showed that the average daily gain of 1 BA group was significantly increased (p < 0.05) when compared to 0 and 1.5 BA groups, while an opposite tendency of dry matter intake to average daily gain ratio was observed. The dry matter, organic matter, neutral detergent fiber and acid detergent fiber digestibility of 1 BA group was significantly increased (p < 0.05) as compared with 0 and 1.5 BA groups as well as plasma albumin content. Also, the urinary hippuric acid and hippurate nitrogen concentrations in 1 and 1.5 BA groups were higher (p < 0.05) than those in 0 and 0.5 BA groups. Additionally, the nitrogen intake in 0.5 and 1 BA groups was significantly increased (p < 0.05) when compared to other groups. At 1 h after morning feeding, the plasma benzoic acid concentration of 1 BA group reached up to maximum value and was higher (p < 0.05) than other groups, and then began to decrease. Similarly, the hippuric acid concentration in plasma of 1 and 1.5 BA groups was higher (p < 0.05) than that of 0 BA group from 1 to 4 h post morning feeding. At 3 h after feeding, the urea nitrogen concentration in plasma of 0 BA group was higher (p < 0.05) than that of 1.5 BA group. Overall, the appropriate supplementation of benzoic acid (1%) in the diet can improve growth performance and nitrogen metabolism of weaned lambs.