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Despite their role in host nutrition, the anaerobic gut fungal (AGF) component of the herbivorous gut microbiome remains poorly characterized. Here, to examine global patterns and determinants of AGF diversity, we generate and analyze an amplicon dataset from 661 fecal samples from 34 mammalian species, 9 families, and 6 continents. We identify 56 novel genera, greatly expanding AGF diversity beyond current estimates (31 genera and candidate genera). Community structure analysis indicates that host phylogenetic affiliation, not domestication status and biogeography, shapes the community rather than. Fungal-host associations are stronger and more specific in hindgut fermenters than in foregut fermenters. Transcriptomics-enabled phylogenomic and molecular clock analyses of 52 strains from 14 genera indicate that most genera with preferences for hindgut hosts evolved earlier (44-58 Mya) than those with preferences for foregut hosts (22-32 Mya). Our results greatly expand the documented scope of AGF diversity and provide an ecologically and evolutionary-grounded model to explain the observed patterns of AGF diversity in extant animal hosts.

Background Vancomycin-resistant enterococci (VRE) represent a public health threat due to the few available treatments. Such alarm has triggered worldwide initiatives to develop effective antimicrobial compounds and novel delivery and therapeutic strategies. vanA operon is responsible for most cases of acquired vancomycin resistance in enterococci. Objectives Development of a transcription factor decoy (TFD) system as a vanA gene transcription-inhibitor. Methods Vancomycin MIC was determined in the presence of TFD-lipoplexes. Additionally, the effect of TFD-lipoplexes on the expression level of the vanA gene and the growth pattern of E. faecalis was evaluated. The haemolytic activity of the developed TFD-lipoplexes and their cytotoxicity were examined. TFD-lipoplexes efficiency in treating vancomycin-resistant E. faecalis (VREF) infection was tested in vivo using a systemic mice infection model. Results A reduction in vancomycin MIC against VRE from 256 mg/L (resistant) to 16 mg/L (intermediate susceptible), in the presence of TFD-lipoplexes, was recorded. The developed TFD-lipoplexes lacked any effect on E. faecalis growth and significantly reduced the transcription level of the vanA gene by about 3-fold. In an initial evaluation of the safety of TFD-lipoplexes, they were found not to be overtly haemolytic to human blood or cytotoxic to human skin fibroblast cells. The co-administration of TFD-lipoplexes and vancomycin efficiently eradicated VREF infection in vivo. Conclusions The developed TFD-lipoplexes successfully restored vancomycin activity against VREF. They offer a safe effective unconventional therapy against this stubborn organism and present a revolution in gene therapy that can be applied to other resistance-encoding genes in various organisms. [ABSTRACT FROM AUTHOR]

Background: Enterococci, known for their disturbing involvement in nosocomial infections, possess a diverse set of virulence factors, regulated by multiple genes. A key virulence regulator is the fecal Streptococcus regulator (Fsr) quorum sensing system. Multiple reports describe the involvement of fsr genes in several virulence mechanisms, notably gelatinase production and biofilm formation; however, the presence of fsr genes does not necessarily predict those virulence phenotypes. This study investigates the factors affecting the relation between molecular detection of fsr genes and accurate prediction of gelatinase activity and biofilm formation intensity. Methods: One hundred enterococcal samples were collected from patients suffering from urinary tract infections. The isolates were identified through the use of a polymerase chain reaction (PCR) technique targeting the ddl gene. Biofilm formation was quantified by the crystal violet assay, while gelatinase activity was evaluated on gelatin agar plates. PCR was used to detect the fsrA and fsrB genes, as well as the gelatinase enzyme-encoding gene (gelE). Results: Out of the collected 100 isolates, 93% were identified as Enterococcus faecalis. The isolates formed biofilm with different intensities: 47% were strong biofilm producers, 28% moderate, and 21% weak, while only four isolates (4%) did not form biofilm. Only 14% of all isolates had detectable gelatinase activity. The fsrA and fsrB genes were detected in 26% and 28% of the tested isolates, respectively, while gelE was detected in 57% of the isolates. Whereas no association was found between biofilm formation intensity and fsr locus genes or gelatinase activity, a strong positive correlation (r = 1) was found between the detection of both fsrA and fsrB genes and the gelatinase activity. Conclusion: fsrA and fsrB have a diagnostic value and may be used as biomarkers for gelatinase activity in E. faecalis. [ABSTRACT FROM AUTHOR]

Objectives: We set out to investigate the prevalence, different mechanisms, and clonal relatedness of multidrug resistance (MDR) among third-generation cephalosporin-resistant Gramnegative clinical isolates from Egypt. Materials and methods: A total of 118 third-generation cephalosporin-resistant Gramnegative clinical isolates were included in this study. Their antimicrobial susceptibility pattern was determined using Kirby-Bauer disk diffusion method. Efflux pump-mediated resistance was tested by the efflux-pump inhibitor-based microplate assay using chlorpromazine. Detection of different aminoglycoside-, β-lactam-, and quinolone-resistance genes was done using polymerase chain reaction. The genetic diversity of MDR isolates was investigated using random amplification of polymorphic DNA. Results: Most of the tested isolates exhibited MDR phenotypes (84.75%). The occurrence of efflux pump-mediated resistance in the different MDR species tested was 40%-66%. Acinetobacter baumannii isolates showed resistance to most of the tested antibiotics, including imipenem. The blaOXA-23-like gene was detected in 69% of the MDR A. baumannii isolates. The MDR phenotype was detected in 65% of Pseudomonas aeruginosa isolates, of which only 23% exhibited efflux pump-mediated resistance. On the contrary, efflux-mediated resistance to piperacillin and gentamicin was recorded in 47.5% of piperacillin-resistant and 25% of gentamicin-resistant MDR Enterobacteriaceae. Moreover, the plasmid-mediated quinolone-resistance genes (aac(6')-Ib-cr, qnrB, and qnrS) were detected in 57.6% and 83.33% of quinolone-resistant MDR Escherichia coli and Klebsiella pneumoniae isolates, respectively. The β-lactamase-resistance gene blaSHV-31 was detected for the first time in one MDR K. pneumoniae isolate from an endotracheal tube specimen in Egypt, accompanied by blaTEM-1, blaCTX-M-15, blaCTX-M-14, aac(6')-Ib-cr, qnrS, and multidrug efflux-mediated resistance. Conclusion: MDR phenotypes are predominant among third-generation cephalosporin-resistant Gram-negative bacteria in Egypt and mediated by different mechanisms, with an increased role of efflux pumps in Enterobacteriaceae. [ABSTRACT FROM AUTHOR]

Background: Bacterial infections are considered as one of the major global health threats, so it is very essential to design and develop new antibacterial agents to overcome the drawbacks of existing antibacterial agents., Methods: The aim of this work is to synthesize a series of new fluoroquinolone-3-carboxamide amino acid conjugates by molecular hybridization. We utilized benzotriazole chemistry to synthesize the desired hybrid conjugates., Results: All the conjugates were synthesized in good yields, characterized, evaluated for their antibacterial activity. The compounds were screened for their antibacterial activity using methods adapted from the Clinical and Laboratory Standards Institute. Synthesized conjugates were tested for activity against medically relevant pathogens; Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27856) Staphylococcus aureus (ATCC 25923) and Enterococcus faecalis (ATCC 19433)., Conclusion: The observed antibacterial experimental data indicates the selectivity of our synthesized conjugates against E.Coli. The protecting group on amino acids decreases the antibacterial activity. The synthesized conjugates are non-toxic to the normal cell lines. The experimental data were supported by computational studies., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Microbiome projects are currently booming around the globe, enabled by advances in culture-independent microbial community analysis and high-throughput sequencing. One emerging application of microbiome science involves exploring microbial diversity in built environments, and one unexplored built environment is the pharmaceutical factory, notably factories producing antibiotics, as they could be enriched in antibiotic-resistant microbes. To examine the drug factory microbiome, we launched this interdisciplinary hypothesis-generating study to benchmark culture-independent microbiome analysis in drug manufacturing units producing antibiotics and nonantibiotic drugs, against traditional microbial identification and quantification techniques. Over a course of 4 months, we prospectively collected 234 samples from antibiotic (kanamycin and amoxicillin) and nonantibiotic (acetaminophen) production clean rooms within a pharmaceutical factory in Egypt. All samples were analyzed by traditional culture-based methods, and microbial communities of representative samples were profiled by16S rRNA gene sequencing. In addition, antibiotic resistance profiles of some samples were determined, and representative resistance genes were screened. The 16S rRNA analysis revealed a typical predominance of Proteobacteria (36%), Firmicutes (31%), and Bacteroidetes (16%). The microbial composition of the samples was highly affected by the use of water, environmental conditions during the production process, the presence of personnel, and the type of the product. The effect of these factors was confirmed by total aerobic microbial counts and identification of biomarker microbes. In conclusion, these observations can aid in the future for optimal design and management of pharmaceutical manufacturing units, and speak to a greater need for implementing microbiome research in the quality assurance of built environments.