Methicillin-resistant Staphylococcus aureus (MRSA) is a serious zoonotic pathogen that poses significant threats to both public health and the poultry industry due to its multidrug resistance and virulence. In broiler chickens, MRSA infections are commonly associated with arthritis, resulting in impaired mobility, reduced productivity, and economic losses. This study aimed to investigate the epidemiology, antimicrobial resistance profiles, and genetic determinants of MRSA in broiler chickens presenting with clinical arthritis in the Kafr El-Sheikh Governorate, northern Egypt. In this study, 100 broiler farms were randomly selected from a list provided by the local veterinary authority in Kafr El-Sheikh Governorate. Of these, 20 medium-sized farms (5000-10,000 birds per cycle) had clinically arthritic chickens. A total of 140 synovial fluid samples (six to eight chickens per farm) were aseptically collected from affected birds. The affected farms represented approximately 4.8% of the total broiler farms in the governorate and were distributed across different districts, indicating that MRSA-associated arthritis was not confined to a single locality. Bacterial isolation was performed using selective culture media and confirmed via biochemical tests and PCR targeting the nuc gene. Antimicrobial susceptibility testing was conducted using the Kirby Bauer disk diffusion method against 16 antibiotics following CLSI 2020 guidelines. Molecular screening for resistance and virulence genes (mecA, vanA, hig) was performed by uniplex PCR. Phylogenetic analysis of 16S rRNA sequences was carried out using the Maximum Likelihood method. Clinical signs included joint swelling, deformity, and impaired locomotion. Epidemiological analysis revealed that MRSA-associated arthritis was detected in (3/20) 15% of infected farms, with 7.67 ± 1.53% of birds affected within infected flocks. Staphylococcus aureus was isolated from 60% of footpad abscesses and 65% of hock joint swellings. All isolates were resistant to multiple β-lactam antibiotics, including oxacillin, cefoxitin, penicillin G, and piperacillin. High resistance was also observed to clindamycin, cephradine, and cephalexin. The most effective agents were ampicillin-sulbactam and vancomycin. The mecA and nuc genes were detected in all isolates, and vanA and hig genes were detected in 5% and 25% of isolates, respectively. Phylogenetic analysis confirmed the close genetic relatedness of the local isolate (PQ879639.1) to global S. aureus strains. MRSA is an emerging pathogen in broiler flocks with a marked capacity for antimicrobial resistance and zoonotic transmission. The detection of multidrug-resistant strains carrying key resistance genes highlights the urgent need for enhanced biosecurity, prudent antimicrobial use, and routine monitoring programs to mitigate its impact on poultry and public health.

Pseudomonas aeruginosa is a common pathogen of a wide range of nosocomial infections in humans, as well as foodborne illnesses. The current study focuses on the molecular genotyping of P. aeruginosa recovered from human, water, and food specimens. A total of 350 samples, fifty samples each from human, tap water, fish swamp, chicken meat, minced meat, raw milk, and hospital surface from the Menoufiya governorate, Egypt. P. aeruginosa was detected in 14.28%, including human (26%), tap water (18%), fish swamp (18%), chicken meat (12%), minced meat (10%), raw milk (16%), and hospital surface (0%). The results of testing of 50 P. aeruginosa isolates against sixteen antibiotics revealed a relatively high antibiotic resistance for Amoxicillin (100%), Erythromycin (98%), Cephradine (90%), Colistin (82%), Oxytetracyclin, (79%), Chloramphenicol (70%), Doxycycline (70%), and Kanamycin (62%) and high susceptibility for Imipenem (96%), Apramycin (94%), Amikacin (90%), Norfloxacin (78%), Sulphamethoxazol (86%), Enrofloxacin (64%), and Ofloxacin (60%). Furthermore, PCR was successfully amplified for the toxA, exoS, and oprL virulence genes at 396, 118, and 504 bp, respectively, as well as amplifying the ermB, pelA, blaTEM, and tetA resistance genes at 639, 786, 516, and 570 bp, respectively. The dendrogram investigation by ERIC-PCR of 10 clinical P. aeruginosa isolates revealed two main clusters and 10 different ERIC-PCR patterns. The presence of P. aeruginosa isolates in food may represent a potential public health concern, with the need for further epidemiological studies, as well as whole-genome sequencing and correlations of P. aeruginosa in water, food samples, and human infections.

As a novel study, a newly formulated electroless biocide amphiphilic coating protected brass alloy in artificial seawater contaminated with bacteria. A new galvanic cell is represented for electroless deposition. The adherent polymeric complex of formula [Sn(tetra dentate ligand cephradine)Cl] was deposited. Synergism of tin and cephradine in the coating improved the antibacterial activity, as shown by a lower MIC than native cephradine antibiotic. The insulating, adherent coating surface film protected the brass alloy against microbiologically induced corrosion and showed no biofilm formation, as the compatible coating constituents kill and stop bacterial growth. The delocalized electron (s) permeated lipid layers and penetrated the microbial cell membrane, forming hydrogen bonds with active centers on the constituents of bacterial cells, perturbing respiration and killing bacteria. Polymerization decreased the polarity of the tin coating, increasing its lipophilicity and enhancing penetration. The electrochemical parameters (increased charge transfer resistance (Rct), reduced capacitance of the electrical double layer (Qdl) indicated a capacitive insulating coating. The low limiting dissolution current (156 mA cm[-2] for 0.00013 M organotin, compared to 250 mA cm[-2] for the blank sample) confirmed the inhibition of microbial corrosion by the organotin coating. However, the predominant form of corrosion is pitting corrosion.

Penicillin G acylases (PGAs) are industrially important enzymes primarily used for the synthesis of first- and second-generation cephalosporins or penicillins. This study aims to establish a high-efficiency biosynthetic system for cefradine on the purpose of significantly enhancing its catalytic efficiency in cefradine synthesis and developing its potentials for industrial application. In this study, we identified and engineered penicillin G acylase and obtained a highly active mutant KsPGA M7(M168F/F313G) for the synthesis of cefradine. The mutant achieved a conversion rate over 95% in the scaled-up reaction. To validate its industrial applicability, we immobilized both the wild-type and mutant enzymes and applied them in continuous flow reactions, which achieved a space-time yield of 2 800 g/(L·d). This study lays a foundation for the future applications of penicillin G acylases in the industrial synthesis of cefradine.

Wound therapy has long been a complex challenge within the medical field. The parameters at the wound area change constantly, presenting a significant challenge in monitoring wound conditions for guiding drug release and enabling real-time therapy. Herein, a hierarchically structured hydrogel, composed of a supramolecular hydrogel with bactericidal activity and a polymer hydrogel promoting wound healing, was designed and fabricated using physical crosslinking method. This hierarchically structured hydrogel could serve as wound dressing. Specifically, physicochemical properties testing indicates that the hierarchically structured hydrogel exhibits tunable rheological property, high swelling and similar mechanical properties to human skin. The drug release in vitro proved that cephradine would be released quickly at pH 5.0 and hyaluronic acid would be dissociated easily at pH 7.5, aligning perfectly with the processes of wound disinfection and healing. Moreover, clinical animal experiments showed that the hierarchically structured hydrogel significantly enhances the granulation tissue thickness, improves vascularization and collagen deposition, thereby promoting wound healing more effectively than the commercial films. Notably, the hierarchically structured hydrogel's excellent conductivity and multiple stimulus response behaviors allow for real-time monitoring physiological environment of wounds and drug release, thereby promoting digital remote diagnosis and personalized treatment.

Broilers farming has been suffering from multiple challenges, including extensive application of antibiotics. Probiotics-supplemented feed might serve as an efficient alternative to these growth stimulants. We designed the present study to isolate bacteria from chickens' gut and analyze their probiotic characteristics. For isolation, the serial dilution method and De Man-Rogosa-Sharpe agar (MRS) medium were used. Isolates were characterized via biochemical and ribotyping analysis, growth study, antimicrobial and antibiotic sensitivity profiling, acid and bile salt tolerance, intestinal adhesion and cholesterol degradation assays. Four isolates were identified as Enterococcus durans strain PUPro5, Lactobacillus acidophilus strain PUPro6, Enterococcus durans strain PUPro7 and Ligilactobacillus salivarius strain PUPro8. The highest growth rate was observed in E. durans strain PUPro7 with OD600 = 1.929 ± 0.001 and start of log phase after 3 h. All isolates showed maximum intestinal cell adhesion at 90 min, ranging between 423 and 588.67 CFUs/ml. All isolates demonstrated maximum tolerance potential at 2% concentration of NaCl with L. salivarius strain PUPro8 being the most efficient among all isolates. The highest resistance to bile salts was observed in L. acidophilus strain PUPro6 with an optimum OD600 of 1.748 at log phase. All bacteria demonstrated antimicrobial resistance against Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus subtilis and B. proteus. Maximum tolerance was observed in L. acidophilus strain PUPro6 (OD600 = 1.344 ± 0.017) against P. aeruginosa, L. salivarius strain PUPro8 (OD600 = 1.304 ± 0.003) against B. subtilis, E. durans strain PUPro5 (OD600 = 1.294 ± 0.066) against S. aureus and E. durans strain PUPro7 (OD600 = 1.216 ± 0.002) against B. proteus. All isolates were sensitive against all the antibiotics, with maximum zone of inhibition against velosef and cefadroxil in the E. durans strain PUPro5. Cholesterol degradation efficiency of isolates ranged between 195.2 and 204.6 mg/dl. Bacteria characterized in the present study exhibit probiotic potential and can be recommended for testing their effect on chickens' growth and meat quality through broiler diet supplementation.

The significant global impact of tuberculosis (TB) on human health is exacerbated by the increasing prevalence of multi-drug resistant tuberculosis (MDR-TB) and the challenges of novel drug discovery for the treatment of drug-susceptible and drug-resistant strains of M. tuberculosis. Rifampicin is a key first-line TB drug and rifampicin resistance is a major obstacle to treating MDR-TB. Utilising existing antimicrobial drugs to supplement combination therapy and overcome rifampicin resistance is a promising solution due to their widespread availability and proven clinical safety profile. Therefore, this study aimed to explore the feasibility of using beta-lactam/beta-lactamase inhibitor combinations with rifampicin to inhibit the growth of multidrug-resistant M. tuberculosis. Based on inhibitory concentration (IC), oral bioavailability, pricing, commercial availability, five beta-lactams and the beta-lactamase inhibitor, clavulanate, were selected for testing. These were combined with rifampicin for in vitro testing against Mycobacterium tuberculosis H37Rv. Resazurin assays and colony forming unit (CFU) enumeration were used to quantify drug efficacy, Chou-Talalay calculations were performed to identify drug synergy and Chou-Martin calculations were performed to quantify drug dose reduction index (DRI). The combination of tebipenem-clavulanate/rifampicin and cephradine-clavulanate/rifampicin were found to be synergistic and highly effective against clinical isolates of MDR-TB, overcoming rifampicin resistance in vitro. Beta-lactam synergy may provide viable combination therapies with rifampicin to address the issue of drug resistance in TB.

In the original publication [...].

Due to consumer demand, many conventional poultry farms are now growing poultry without antibiotics or synthetic chemicals. In addition to this, pasture/organic poultry farms have increased significantly in the USA, and they are also antibiotic- and chemical-free. According to recent reports, both antibiotic-free conventional and pasture poultry farmers are facing the re-emergence of bacterial diseases. Bacterial diseases cause higher mortality rates in birds and lead to non-profitable poultry farming. This study investigated the prevalence of Salmonella enterica subsp. enterica serovar Gallinarum biovars Gallinarum (S. Gallinarum), the causative agent of fowl typhoid, and Salmonella enterica subsp. enterica serovar Gallinarum biovars Pullorum (S. Pullorum), the causative agent of pullorum disease, within integrated crop-livestock/pasture farm environments and their processed products. Specifically, the study focused on both the pre-harvest period, which includes the conditions and practices on the farm before the crops and livestock are harvested, and the post-harvest period, which encompasses the handling, processing, and storage of the products after harvest. A total of 1286 samples were collected from six farms and adjacent 13 markets to determine the prevalence of S. Gallinarum and S. Pullorum by using both microbiological culture and molecular techniques, specifically PCR. Antimicrobial susceptibility testing was performed using the agar dilution method for the recommended antibiotics as described in the Clinical Laboratory Standards Institute (CLSI). S. Pullorum was detected in 11 samples (2.7%), while S. Gallinarum was found in six samples (1.5%) out of a total of 403 samples at the pre-harvest level. At the post-harvest level, only S. Gallinarum was identified in 14 meat samples out of 883(1.6%) recovered from samples collected from retail markets. Antibiogram showed S. Gallinarum and S. Pullorum to be highly resistant to cephradine, trimethoprim-sulfamethoxazole, amoxicillin, streptomycin, and ampicillin. This data demonstrates that both S. Pullorum and S. Gallinarum are commonly present in farm poultry environments as well as the products sold in the markets, which warrants implementation of regular surveillance and monitoring programmes, as well as potentially requiring future control strategies to reduce S. Pullorum and S. Gallinarum transmission.

Clostridioides difficile infection (CDI) is the most common nosocomial infection in the US. CDI has become a growing concern due to C. difficile's resistance to several antibiotics, including cephalosporins. Furthermore, patients administered cephalosporins are at higher risk of contracting CDI. Cephalosporins are β-lactam antibiotics, which prevent bacterial cell wall synthesis by inhibiting penicillin-binding proteins (PBPs). β-lactam-resistant bacteria evade these antibiotics by producing β-lactamases or by harboring low-affinity PBPs. A genomic analysis of C. difficile strain 630 identified 31 putative β-lactam resistance genes. Upon cefoxitin exposure, few C. difficile strain 630 putative antibiotic-resistant genes were overexpressed. Most notably, the β-lactamase blaCDD gene was upregulated approximately 600-fold, as previously reported. Deletion of the blaCDD locus did not change in cephalosporin susceptibility. Deletion of the second most upregulated gene, the PBP vanY, was also ineffective at decreasing cephalosporin resistance. Cefoxitin exposure of the C. difficile strain 630ΔblaCDD mutant did not increase upregulation of other putative antibiotic resistance genes compared to wildtype C. difficile strain 630. Transcriptomic analyses of wildtype C. difficile strain 630 exposed to cephradine, cefoxitin, ceftazidime, or cefepime revealed the shared upregulation of a putative heterodimeric ABC transporter encoded by loci CD630_04590 (ABC transporter ATP-binding protein) and CD630_04600 (ABC transporter permease). These genes are genomically located directly downstream of blaCDD (CD630_04580). The deletion mutant CD630_04600 remained resistant to a number of antibiotics. Thus, even though blaCDD, CD630_04590, and CD630_04600 are all upregulated when exposed to cephalosporins, they do not seem to be involved in antibiotic resistance in C. difficile strain 630.