Momen Askoura

In the original publication, there was a mistake in Figure 7B as published

Background: The present study aims to improve safety and quality assurance of swimming pools located in Sharkia governorate, Egypt. A total of 144 water samples were collected from eight pools. The water quality of the tested pools was assessed according to national swimming pool quality standards in terms of physiochemical and microbial characterization. Microbial contamination was assessed by the detection and enumeration of standard indicator organisms. 16S rDNA sequencing and phylogenetic analysis were utilized for further identification of most resistant bacterial isolate. Antimicrobial susceptibility to various natural potentially antimicrobial agents; including aqueous, alcoholic plant extracts and essential oils was conducted. Both MIC and MBC for tested natural antimicrobial agents were determined. Finally, field application of the most effective antimicrobial agents was carried out to highlight the cons and pros of their usage in field, in order to possess a broader scope of both theoretical and practical aspects of this study. Results: In terms of physical analysis; 82.9% of tested samples were nonconformed to temperature standard, while 100% were conformed to color and odor. Regarding chemical analysis; 54.3% and 53.3% of samples were nonconformed to alkalinity and combined chlorine, respectively. Assessment of microbial contamination indicated the prevalence of Pseudomonas aeruginosa as a main contaminator of tested pool water (57.1%) followed by total coliforms which ranked second among detected microorganisms (52.4%). Upon performing antimicrobial susceptibility testing of plant extracts and essential oils, cinnamon hot water extract and essential oil showed narrowest MIC ranges. Upon testing various combinations between different tested antimicrobial agents, combination of cinnamon hot water extract and clove essential oil was identified as a promising synergetic combination against resistant isolates. In field application of the most effective antimicrobial compounds resulted in that compatibility markedly decreased for physical standards and slightly for chemical standards. However, microbial pollution was totally eliminated after treatment, which was considered and discussed within the context of the study. Conclusion: This study targeted full assessment of pools water in Egypt, one of the most prominent findings of this study is prevalence of P. aeruginosa as the main resistant microorganism responsible for microbial pollution of pool water. Cinnamon hot water extract and clove essential oil were identified as the most effective natural antimicrobial agents used in the study. Field application of these antimicrobial agents was a significant step confirming the validity and credibility of current results highlighting the pros and cons of practical application of the suggested pool decontaminators.

The rise of deaths by resistant bacteria is a global threat to public health systems. Klebsiella pneumoniae is a virulent pathogen that causes serious nosocomial infections. The major obstacle to bacterial treatment is antibiotic resistance, which necessitates the introducing of alternative therapies. Phage therapy has been regarded as a promising avenue to fight multidrug-resistant (MDR) pathogens. In the current study, a novel phage vB_KpnP_KP17 was isolated from sewage, and its lytic potential was investigated against K. pneumoniae. The isolated phage vB_KpnP_kP17 was lytic to 17.5% of tested K. pneumoniae isolates. One step growth curve indicated a virulent phage with a short latent period (20 min) and large burst size (331 PFU/cell). Additionally, vB_KpnP_kP17 maintained its activity against planktonic cells over a wide range of pH, temperature and UV irradiation intervals. The potential of vB_KpnP_KP17 as antibiofilm agent was revealed by the biofilm inhibition assay. The isolated phage vB_KpnP_KP17 at multiplicity of infection (MOI) of 10 inhibited more than 50% of attached biofilms of tested K. pneumoniae isolates. The genome of vB_KpnP_kP17 was characterized and found to be a linear dsDNA of 39,936 bp in length and GC content of 52.85%. Additionally, the absence of toxicity, virulence and antibiotic resistance genes further confirms the safety of vB_KpnP_KP17 for clinical applications. These characteristics make vB_KpnP_KP17 of a potential therapeutic value to manage MDR K. pneumoniae infections. Additionally, the formulation of vB_KpnP_KP17 in a cocktail with other lytic phages or with antibiotics could be applied to further limit biofilm-producing K. pneumoniae infections.

Aim: The current study aimed to establish a phenotypic and genotypic characterization record of a novel lytic bacteriophage (phage) against multidrug-resistant (MDR) Escherichia coli (E. coli) infections. Methods and Results: Phenotypic characterization of the isolated phage included the assessment of phage morphology, host range, stability, and antibiofilm activity. The isolated phage vB_EcoM_ECO78 demonstrated a high lytic activity against MDR E. coli and E. coli serotypes O78: K80: H12 and O26: H11. Additionally, it showed a marked antibiofilm activity and high physical stability at a wide range of temperatures and pH. Genotypic investigations identified a double-stranded DNA genome of 165 912 base pairs (bp) spanning 258 open reading frames (ORFs), out of which 149 ORFs were identified and annotated. In vivo analysis further confirmed the therapeutic potential of vB_EcoM_ECO78 which effectively increased the survival of mice infected with MDR E. coli. Conclusion: The isolated phage vB_EcoM_ECO78 exhibits considerable stability and antibiofilm activity against MDR E. coli isolates, supported by notable environmental fitness and in vivo antibacterial capability.

The increasing prevalence of multidrug-resistant bacteria imminently threatens public health and jeopardizes nearly all aspects of modern medicine. The Burkholderia cepacia complex (Bcc) comprises Burkholderia cepacia and the related species of Gram-negative bacteria. Members of the Bcc group are opportunistic pathogens responsible for various chronic illnesses, including cystic fibrosis and chronic granulomatous disease. Phage therapy is emerging as a potential solution to combat the antimicrobial resistance crisis. In this study, a temperate phage vB_BceM_CEP1 was isolated from sewage and fully characterized. Transmission electron microscopy indicated that vB_BceM_CEP1 belongs to the family Peduoviridae. The isolated phage demonstrated enhanced environmental stability and antibiofilm potential. One-step growth analysis revealed a latent period of 30 min and an average burst size of 139 plaque-forming units per cell. The genome of vB_BceM_CEP1 consists of 32,486 bp with a GC content of 62.05%. A total of 40 open reading frames were annotated in the phage genome, and none of the predicted genes was annotated as tRNA. Notably, genes associated with antibiotic resistance, host virulence factors, and toxins were absent from the vB_BceM_CEP1 genome. Based on its unique phenotype and phylogeny, the isolated phage vB_BceM_CEP1 is classified as a new temperate phage with lytic activity. The findings of this study enhance our understanding of the diversity of Bcc phages.

Background: Pseudomonas aeruginosa is a nosocomial bacterium responsible for variety of infections. Inappropriate use of antibiotics could lead to emergence of multidrug-resistant (MDR) P. aeruginosa strains. Herein, a virulent phage; vB_PaeM_PS3 was isolated and tested for its application as alternative to antibiotics for controlling P. aeruginosa infections. Methods: Phage morphology was observed using transmission electron microscopy (TEM). The phage host range and efficiency of plating (EOP) in addition to phage stability were analyzed. One-step growth curve was performed to detect phage growth kinetics. The impact of isolated phage on planktonic cells and biofilms was assessed. The phage genome was sequenced. Finally, the therapeutic potential of vB_PaeM_PS3 was determined in vivo. Results: Isolated phage has an icosahedral head and a contractile tail and was assigned to the family Myoviridae. The phage vB_PaeM_PS3 displayed a broad host range, strong bacteriolytic ability, and higher environmental stability. Isolated phage showed a short latent period and large burst size. Importantly, the phage vB_PaeM_PS3 effectively eradicated bacterial biofilms. The genome of vB_PaeM_PS3 consists of 93,922 bp of dsDNA with 49.39% G + C content. It contains 171 predicted open reading frames (ORFs) and 14 genes as tRNA. Interestingly, the phage vB_PaeM_PS3 significantly attenuated P. aeruginosa virulence in host where the survival of bacteria-infected mice was markedly enhanced following phage treatment. Moreover, the colonizing capability of P. aeruginosa was markedly impaired in phage-treated mice as compared to untreated infected mice. Conclusion: Based on these findings, isolated phage vB_PaeM_PS3 could be potentially considered for treating of P. aeruginosa infections.

Pseudomonas aeruginosa is an important pathogen that causes serious infections. Bacterial biofilms are highly resistant and render bacterial treatment very difficult, therefore necessitates alternative antibacterial strategies. Phage therapy has been recently regarded as a potential therapeutic option for treatment of bacterial infections. In the current study, a novel podovirus vB_PaeP_PS28 has been isolated from sewage with higher lytic activity against P. aeruginosa. Isolated phage exhibits a short latent period, large burst size and higher stability over a wide range of temperatures and pH. The genome of vB_PaeP_PS28 consists of 72,283 bp circular double-stranded DNA, with G + C content of 54.75%. The phage genome contains 94 open reading frames (ORFs); 32 for known functional proteins and 62 for hypothetical proteins and no tRNA genes. The phage vB_PaeP_PS28 effectively inhibited the growth of P. aeruginosa planktonic cells and displayed a higher biofilm degrading capability. Moreover, therapeutic efficacy of isolated phage was evaluated in vivo using mice infection model. Interestingly, survival of mice infected with P. aeruginosa was significantly enhanced upon treatment with vB_PaeP_PS28. Furthermore, the bacterial load in liver and kidney isolated from mice infected with P. aeruginosa and treated with phage markedly decreased as compared with phage-untreated P. aeruginosa-infected mice. These findings support the efficacy of isolated phage vB_PaeP_PS28 in reducing P. aeruginosa colonization and pathogenesis in host. Importantly, the isolated phage vB_PaeP_PS28 could be applied alone or as combination therapy with other lytic phages as phage cocktail therapy or with antibiotics to limit infections caused by P. aeruginosa.