Staphylococcus aureus (S. aureus) is a commensal bacterium and an opportunistic pathogen causing a wide variety of infections ranging from localized skin and soft tissue infections to life-threatening severe bacteremia, osteomyelitis, endocarditis, atopic dermatitis, prosthetic joint infection, staphylococcal food poisoning, medical device-related infections, and pneumonia. It is attributed to an acquired resistant gene, mecA, encoding penicillin-binding protein 2a (PBP2a). PBP2a is an essential protein responsible for the resistivity of methicillin-resistant S. aureus (MRSA) to various beta-lactam antibiotics. The antimicrobial treatment alternatives for MRSA are increasingly limited. Therefore, developing alternative therapeutic options for its treatment is the need of the day. Phthalimides and their N-substituted derivatives are of biological importance as they possess extensive biological and pharmaceutical properties and can serve as an excellent therapeutic option for MRSA. This study uses three chiral phthalimides (FIA, FIB, and FIC) to check their in silico and in vitro inhibitory effects. Molecular docking of these chiral phthalimides against PBP2a of MRSA was performed initially. After promising results, these novel compounds were screened through the agar-well diffusion method and micro-broth dilution assay to investigate their in vitro inhibitory activities with FIB being the strongest anti-staphylococcal agent yielding a 21 mm zone of inhibition and a minimum inhibitory concentration (MIC) of 0.022 ug, respectively. The zones of inhibition obtained through the in vitro activity showed that these chiral phthalimides possess substantial anti-MRSA activities and have the potential to be considered as alternative chemotherapeutics to treat the infections caused by MRSA after the confirmation of their cytotoxic and pharmacokinetic studies.

This study aimed to formulate polymer-based chitosan nanoparticles as a drug (miltefosine) delivery system for treating leishmaniasis. Miltefosine-loaded chitosan nanoparticles (MLCNPs) have been synthesized and then characterized by the use of UV-visible spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), the zeta potential, drug loading content (DLC), encapsulation efficacy (EE) and the dynamic light scattering technique (DLS). Further, the in vitro anti-leishmanial activity of the characterized chitosan nanoparticles was assessed by a microculture tetrazolium (MTT) assay, and in vivo efficacy was evaluated in infected BALB/c mice. The lesion healing was statistically analyzed using Wilcoxon signed-rank and Mann–Whitney tests. The MLCNPs were spherical-shaped (97.5 nm), which presented efficient encapsulation (97.56%), drug loading content (91.5 µg/mL) and a positive surface charge (+1.04 mV). MLCNPs were less hemolytic (6%) when compared to conventional miltefosine. MLCNPs (50 µg/mL) showed a potential antileishmanial effect (mean viability: 10 ± 0.3%) on promastigotes in comparison to conventional miltefosine (mean viability: 18 ± 1.3%). The IC50 value for MLCNPs and miltefosine was 0.0218 µg/mL and 0.3548 µg/mL, respectively. This in vivo study proved that lesions of mice treated with oral and intralesional-injected MLCNPs significantly heal (p = 0.01). MLCNPs have a significant antileishmanial effect and could be utilized as an alternative treatment for CL.

In the present work, several new glycoconjugates (8a–e) were generated from glycopyranosyl-α-trichloroacetimidates (sugar-OTCA) as glycosyl donors and dimethyl-l-tartrate as an aglycone acceptor in good to excellent yields. In the synthetic protocol, various monosaccharides were transformed into pentaacetylated derivatives and then into glycopyranosyl-α-trichloroacetimidates. Afterward, the sugar-OTCA was reacted with dimethyl-l-tartrate using Schmidt’s trichloroacetimidate protocol to give the desired products. The newly synthesized glycoconjugates were characterized by FT-IR, ¹H, and ¹³C-NMR spectroscopic analytical methods. All the target compounds (8a–e) were tested in vitro against various strains of bacteria and fungi at different concentrations. The results revealed that the target compounds had encouraging antibacterial and antifungal potential. The antileishmanial activity of the target compounds against Leishmania tropica promastigotes was also investigated. The in vitro results were further supported by the in silico docking study that indicated minimum values of the docking scores and binding energies for the resulting complexes obtained by the favorable interactions between the target compounds (8a–e) and the selected strains of bacteria and fungi. The docking results proposed promising antibacterial and antifungal activities of the target compounds (8a–e) against the selected bacterial and fungal species.

Background: Cholera, caused by Vibrio cholerae, remains endemic in many developing countries, including Pakistan. The extensive use of antibiotics has led to the emergence of antimicrobial resistance in V. cholerae, limiting available treatment options. In this study, we performed molecular characterisation of antibiotic-resistant V. cholerae serotype Ogawa isolates from a recent cholera outbreak in Khyber Pakhtunkhwa, Pakistan. Methodology: Suspected cholera stool samples were collected from hospitalised patients at various district hospitals of Khyber Pakhtunkhwa Province (KPK), Pakistan. The samples were transported to the Public Health Reference Microbiology Laboratory at Khyber Medical University, Peshawar. V. cholerae were identified based on colonial morphology, Gram staining, and biochemical tests using EPI 10E. For serotype identification, monovalent antisera were used. Antibiotic susceptibility testing (AST) was performed using CLSI M45 and EUCAST guidelines. DNA was extracted from pure colonies of multidrug-resistant (MDR) V. cholerae and subjected to whole-genome sequencing (WGS) for genomic characterisation using an Illumina MiSeq platform. Results: Of the 350 active diarrheal cases investigated, 70 were confirmed as V. cholerae. The outbreak was initially reported in Dir and was subsequently followed by a high incidence of cholera in the Peshawar district of KPK. All strains belong to the Ogawa serotype, which shows high antibiotic resistance, particularly to ampicillin (n = 62, 88.57%), Sulfamethoxazole/Trimethoprim (n = 60, 85.71%), Erythromycin (n = 59, 84.29%), and Tetracycline (n = 53, 75.71%). The lowest resistance was against Meropenem (n = 1, 1.4%), followed by amikacin (n = 7, 10.0%) and levofloxacin (n = 13, 18.57%). Furthermore, 34 (48.57%) of the isolates were MDR, while 13 (18.57%) were extensively drug-resistant. Six samples were selected for whole-genome sequencing. The selection of six V. cholerae samples for WGS was based on their drug resistance pattern and origin of isolation. At the genomic level, all sequenced V. cholerae strains harboured multiple antimicrobial resistance determinants. Quinolone resistance was associated with mutations and genes in gyrA, gyrB, parC, and parE; resistance to sulfamethoxazole–trimethoprim with folA, folP, and dfr; tetracycline resistance with tetA and tet35; chloramphenicol resistance with catB and S10p; and aminoglycoside resistance with hns, S12p, and gigB. In addition, β-lactam resistance was linked to the presence of efflux and β-lactamase genes, including blaSHV and mox-3. Mutations were identified in gyrA at positions S83I, S177A, and S202A, and in parC at positions S85L and I231V. Collectively, the presence of these resistance determinants likely enables V. cholerae to survive exposure to high concentrations of multiple antibiotics. Conclusions: Our V. cholerae isolates showed close genetic relatedness to previously sequenced strains from Pakistan (2010 and 2022), as well as to recently reported international strains from the USA, Australia, and China. These findings highlight both the long-term persistence of these lineages within Pakistan and their international dissemination, likely facilitated by globalisation.