The transferable genetic elements are associated with the dissemination of virulence determinants amongst Klebsiella pneumoniae. Thus, we assessed the correlated antimicrobial resistance in carbapenem-resistant Klebsiella pneumoniae clinical isolates. Each isolate’s ability to biosynthesize biofilm, carbapenemase, and extended-spectrum β-lactamase were examined. Genotypically, the biofilm-, outer membrane porin-, and some plasmid-correlated antimicrobial resistance genes were screened. About 50% of the isolates were multidrug-resistant while 98.4% were extended-spectrum β-lactamase producers and 89.3% were carbapenem-resistant. Unfortunately, 93.1% of the multidrug-resistant isolates produced different biofilm levels. Additionally, fimD and mrkD genes encoding adhesins were detected in 100% and 55.2% of the tested isolates, respectively. Also, the bla_KPC, bla_OXA-48-like, and bla_NDM-encoding carbapenemases were observed in 16.1%, 53.6%, and 55.4% of the tested isolates, respectively. Moreover, the bla_SHV and bla_CTX-M extended-spectrum β-lactamase-associated genes were detected at 95.2% and 61.3%, respectively. Furthermore, aac(3)IIa, qnrB, and tetB resistance-correlated genes were observed in 38.1%, 46%, and 7.9% of the tested isolates, respectively. Certainly, the tested antimicrobial resistance-encoding genes were concurrently observed in 3.2% of the tested isolates. These findings confirmed the elevated prevalence of various antimicrobial resistance-associated genes in Klebsiella pneumoniae. The concurrent transferring of plasmid-encoding antimicrobial resistance-related genes could be associated with the possible acquisition of multidrug-resistant Klebsiella pneumoniae phenotypes.

Background The antibiotic resistance of bacterial pathogens has become a serious health concern and encourages the search for novel and efficient antimicrobial metabolites. There has been a tremendous increase in interest in screening plants and fungi as a source for compounds with antimicrobial activities. Objectives This current study aimed to determine the possible antimicrobial activity of secondary metabolites of the Cladosporium species against some bacteria (Gram positive and Gram negative) and fungi. Method in the current work, Cladosporium were isolated from air in Cairo by using settle plate method. The samples were purified and identified by using macroscopical and microscopical methods, with the aid of biochemical reactions. Antimicrobial activity was performed by using agar well diffusion method. Those with antimicrobial activity subjected to submerged fermentation and metabolites were extracted using ethyl acetate. Extracts are separated by Chromatographic methods, nature of active metabolites was identified by High Performance Liquid Chromatography-Diaiod Array Aided Detector (HPLC-DAD) analysis. The mechanism of antimicrobial activity then investigated by Scan Electron Microscopy (SEM) and Transmission Electron (TEM) Microscopy. Results the current investigation revealed that 5.6% of Cladosporium extracts showed marked antimicrobial activity specially that from C. cladosporioides, C. herbarum and C. cladosporioides species, in addition, by using HPLC-DAD technique revealed the presence of compounds which may be responsible for the antimicrobial activities they elicit, including acropyrone, nigricinol, cladosporin, coumarin, citreoisocoumarin and questinol as major components may be responsible for antimicrobial activity. Scan electron microscopy (SEM) and transmission electron microscopy (TEM) revealed the effect of these compounds on outer surface of tested microorganism. Conclusion Cladosporium species could be a promising source of antimicrobial compounds with pharmaceutical and industrial importance.

Universally Primed-PCR (UP-PCR) and Internal Transcribed Spacer-PCR (ITS-PCR) based genomic fingerprinting techniques are considered a good methods that rely on specifically targeted primers. These techniques, which analyse the rDNA, have been shown to be relatively robust and discriminatory. This study was designed to investigate and characterize the molecular variation among Cladosporium strains collected at different sites in Cairo by using two different fingerprinting methods, Universally Primed- PCR (UP- PCR) and Internal Transcribed Spacer (UP- PCR) technique. The Cladosporium isolates investigated were isolated from air of Cairo by settle plate method. The samples were then purified and identified by using culture based techniques, microscopical methods, and biochemical reactions followed by confirmation in the regional center for mycology and biotechnology (RCMB). Molecular fingerprinting, and genetic similarities among Cladosporium species populations depending onmicrosatellites-polymerase chain reaction (ITS-PCR). Primers used are ITS4, and ITS5. PCR products were digested with 3 restriction enzymes and separated by agarose electrophoresis. Restriction patterns generated by CfoI, Msp < /em>I and RsaI. In addition, we have applied the Universally Primed PCR (UP-PCR) technique using two primers L21 and Fok1.The current work showed prominent discriminatory power given by amplification of internal transcribes spacers PCR regions followed by restriction with CfoI enzyme than other endonucleases. moreover, Fok1 primer revealed minor variability among Cladosporium strains using UP-PCR genotyping technique.

The growing menace of antibiotic resistance demands immediate discovery of new antimicrobial agents. Fungi are a rich source of bioactive secondary metabolites. This study aimed to investigate the antimicrobial and antibiofilm potential of secondary metabolites from airborne Cladosporium species against Gram-positive bacteria. Fungal isolates were collected from atmospheric samples in Cairo, Egypt, using the settle plate technique. From 886 samples, 212 Cladosporium isolates were purified and identified through morphological and molecular (ITS sequencing) characterization, revealing ten species, with C. herbarum as the most prevalent. Antimicrobial activity was assessed via agar well diffusion and broth microdilution assays. Ethyl acetate extracts, particularly from C. cladosporioides-407, exhibited significant activity against pathogens, including Staphylococcus aureus and Bacillus cereus, with minimum inhibitory concentrations (MICs) as low as 64 μg/mL. The C. cladosporioides-407 extract demonstrated potent, dose-dependent inhibition of S. aureus biofilm formation by up to 60% in a crystal violet assay. Time-kill kinetics confirmed its bactericidal activity at 4x MIC, achieving a ≥3-log reduction in CFU/mL within 24 hours. A marked synergy (FICi=0.5) with amoxicillin was revealed by checkerboard assay. Bioassay-guided fractionation and HPLC-DAD analysis of active fractions identified known antimicrobial compounds, including cladosporin, coumarin, and questinol. Transmission electron microscopy of treated bacterial cells revealed severe ultrastructural damage, suggesting a mechanism of action involving cell wall and membrane disruption. These comprehensive findings underscore airborne Cladosporium species, particularly C. cladosporioides, as a highly promising source of synergistic antimicrobial and antibiofilm metabolites for combating resistant Gram-positive pathogens. This underscores their potential for development into novel therapeutic adjuvants to rejuvenate the efficacy of conventional antibiotics.

Background: Microbial infections during pregnancy pose serious risks to both maternal and neonatal health, contributing to high rates of infant mortality. A major global health concern is the increasing prevalence of antibiotic resistance, which complicates treatment strategies. This study aims to investigate the prevalence of Gram-negative bacterial infections among pregnant women in Cairo, Egypt, to identify the antibiotic resistance profiles and elucidate the molecular mechanisms. Methods: the study involved 200 pregnant women aged 20 to 35 years who were facing obstetric problems. The clinics are equipped with advanced diagnostic instruments and in obstetrics and gynecology. All participants were recruited during standard clinic visits and received comprehensive clinical assessments prior to enrollment in the trial. The sample size estimate was predicated on the statistical principles. Isolates were identified using cultural, morphological, and biochemical methods. Antimicrobial susceptibility testing was conducted using the Kirby-Bauer disc diffusion method. Phenotypic analysis included screening for ESBL production tests, AmpC detection, and MBL identification. Molecular methods by PCR amplification, and sequencing of purified products. Results: 187/359 isolates identified as Gram-negative bacteria (52.1%). The most prevalent pathogens were E. coli (52.4%) P value 0.0812. These bacteria exhibited resistance to various antibiotics, with E. coli and K. pneumoniae showing high resistance to beta-lactams (P = 0.889). Phenotypic analysis revealed ESBL production in 21.9% of isolates and AmpC in 19 isolates. Molecular detection using PCR identified ESBL genes (blaTEM, blaSHV, blaOXA-1, blaCTX) and AmpC genes (FOX, DHA, AmpC) in several isolates. Additionally, MBL genes (IMP, VIM, NDM-1, NDM-2) were detected in P. aeruginosa isolates. Conclusion: pregnant women with obstetric complications are at significant risk of multidrug-resistant infections due to the high prevalence of genes associated with ESBLs, AmpC, MBLs, and quinolone resistance. The widespread presence of blaTEM and blaSHV genes underscores the role of horizontal gene transfer in resistance spread.