Brazilian Journal of Microbiology最新文献

{"title":"Assessing the behavior of food handlers wearing face masks and the passage of bacteria through disposable masks.","authors":"Cris Rocha Pinto Magalhães, Nathanyelle Soraya Martins de Aquino, Julia de Moraes Vieira, Claudia Titze Hessel Gonçalves, Eduardo Cesar Tondo","doi":"10.1007/s42770-024-01562-0","DOIUrl":"https://doi.org/10.1007/s42770-024-01562-0","url":null,"abstract":"<p><p>Handlers can wear masks during food preparation to avoid contamination of the nose and mouth. However, if microorganisms can pass through mask layers and handlers touch their outer surfaces, their hands can contaminate the food being handled. This study evaluated the behavior of 31 food handlers wearing disposable masks in a food service kitchen. Next, the microorganisms on the external surface of food handler masks were identified using microbiological methods and matrix-associated laser desorption-time-of-flight (MALDI-TOF) mass spectrometry. Finally, the passage of microorganisms through mask layers was assessed in volunteers. Observations showed that 77.4% of the 31 food handlers touched their masks at least once per hour during food preparation. Microbiological analysis identified 14 bacterial species on all food handlers' masks analyzed. The most frequent microorganisms found were coagulase-negative Staphylococcus, Staphylococcus aureus, and Bacillus spp. The external surfaces of uncontaminated masks showed contamination after volunteers used them for few hours. Furthermore, sterile gloved hands became contaminated after touching the external surfaces of these masks, indicating bacterial transference from the inner to the outer layers. Although masks can prevent direct microbial contamination from the nose and mouth if properly used, our findings indicate that masks may inadvertently become vectors of food cross-contamination if hands touch their external surfaces during food preparation. Since our study indicated that microorganisms can pass through mask layers, food handlers should avoid touching the external surfaces of masks. However, if it happens, they should carry out proper hand washing to prevent food cross-contamination during food preparation.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142766084","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermal and storage stability of novel nutraceuticals combining potential probiotic Limosilactobacillus fermentum strains and freeze-dried jabuticaba [Myrciaria cauliflora (Mart.) O. Berg] peel.","authors":"Heloisa Maria Almeida do Nascimento, Jaielison Yandro Pereira da Silva, Sônia Paula Alexandrino de Oliveira, Karoliny Brito Sampaio, Mariana Monteiro, Fábio Santos de Souza, Eliton Souto de Medeiros, Thatyane Mariano Rodrigues de Albuquerque, Evandro Leite de Souza","doi":"10.1007/s42770-024-01576-8","DOIUrl":"https://doi.org/10.1007/s42770-024-01576-8","url":null,"abstract":"<p><p>This study evaluated the stability of novel nutraceuticals containing jabuticaba freeze-dried peel (FJP) and a mix of potential probiotic L. fermentum strains [139, 263 and 296 (LfM)] (JM: FJP + LfM; JFM: FJB + LfM + fructooligosaccharides) through determination of thermal stability, viable cell counts, bacterial physiological status, phenolic compound contents, and antioxidant activity during 90 days of storage (11% relative humidity, 4 and 25 ºC). JM and JFM were thermally stable, with satisfactory stability in temperature variations. JFM had higher L. fermentum viable cell counts than JM during storage. However, the physiological status of L. fermentum cells in JM and JFM indicated maintenance of vitality and functionality rather than death, regardless of the storage temperature. JM and JFM had a high content of phenolic acids and anthocyanins and antioxidant activity during storage. JFM stored under refrigeration had the most outstanding stability and potential functionality regarding the high viable probiotic cell counts, phenolic compound content, and antioxidant activity.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142766094","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Poultry slaughterhouse wastewater as a source of bacterial antimicrobial resistance.","authors":"Juliana Ferreira Nunes, Thereza Cristina da Costa Patricio, Beatriz Oliveira de Farias, Hosana Dau Ferreira de Souza, Ramon Loureiro Pimenta, Maysa Beatriz Mandetta Clementino, Miliane Moreira Soares de Souza, Irene da Silva Coelho, Shana de Mattos de Oliveira Coelho","doi":"10.1007/s42770-024-01466-z","DOIUrl":"10.1007/s42770-024-01466-z","url":null,"abstract":"<p><p>Slaughterhouses produce huge volumes of effluents throughout the production chain that, when discharged untreated into bodies of water, can become a source of environmental contamination. This is particularly worrisome if these effluents are used for irrigation since they increase contamination levels and spread pathogens and resistance determinants to humans and animals. Therefore, in this study, we assessed antimicrobial resistance in bacteria isolated from inlet water, equalization wastewater tanks, treatment plant wastewater, and treated wastewater in slaughterhouse facilities in Rio de Janeiro, Brazil. Four samples were collected at each of the collection points, between June 2021 and July 2022. Following bacterial isolation and identification, the samples were analyzed for antimicrobial resistance using the disk diffusion method to test aminoglycoside, beta-lactam, and fluoroquinolone antimicrobials. A total of 229 bacteria were isolated, with 74 isolates selected from the genera Citrobacter (12), Enterobacter (14), Klebsiella (35), Serratia (5), and Pseudomonas (8). Inlet water had the lowest number of isolates and was the only point with gentamicin-resistant isolates. Raw effluent from the equalization tank showed the highest number of isolated bacteria and resistance levels, followed by treated wastewater and the treatment plant. Across all samples, a high rate of cefoxitin-resistance was observed among the isolated bacteria. Klebsiella pneumoniae stood out as the species that demonstrated the greatest resistance to a variety of antimicrobials. These results highlight the importance of water quality monitoring in mitigating public health and environmental risks and high antimicrobial resistance levels.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":" ","pages":"3363-3372"},"PeriodicalIF":2.1,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11711597/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141888470","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular characterization and frequency of human pegivirus type 1 (HPgV-1) in kidney transplant recipients from Central-West Brazil.","authors":"Fábio Gonçalves da Silva, Drielly Rodrigues Moura, Pâmela Maria de Oliveira, Tatyane de Souza Cardoso Quintão, Évelin Mota Cassemiro, Gabriel Montenegro de Campos, Anielly Sarana da Silva, Rafael Dos Santos Bezerra, Lorena Aparecida Gonçalves de Noronha, Walter Massa Ramalho, Wildo Navegantes de Araújo, Alex Leite Pereira, Svetoslav Nanev Slavov, Rodrigo Haddad","doi":"10.1007/s42770-024-01490-z","DOIUrl":"10.1007/s42770-024-01490-z","url":null,"abstract":"<p><p>Human Pegivirus Type 1 (HPgV-1), a ubiquitous commensal virus, has been recently suggested as a marker of immunologic function. There is scarce data for the presence, genotypes, and molecular characteristics of HPgV-1 among kidney transplant recipients. Therefore, the objective of this study was to examine the prevalence and the molecular characteristics (cycle threshold, genotypes) of this viral infection among kidney transplant recipients from the Brasília, Federal District of Brazil. HPgV-1 RNA detection in the plasma was assessed by RT-qPCR. Positive samples were submitted to sequencing and phylogenetic analysis of the 5´-UTR portion of the viral genome. The estimated HPgV-1 prevalence among renal-transplant recipients was 20%. The performed phylogenetic inference revealed that the most frequent genotype among these patients was HPgV-1 genotype 2 (78.9%) presented by its two subgenotypes (2 A and 2B), followed by genotypes 1 and 3 (10.5% each). This study presents new data about the HPgV-1 circulation and molecular characteristics among kidney transplant recipients from the Federal District of Brazil. Further work is fundamental to examine the effect of HPgV-1 among patients with immunological suppression, including kidney transplant recipients.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":" ","pages":"3279-3286"},"PeriodicalIF":2.1,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11711997/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142008211","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The gut microbiota of wild birds undergoing rehabilitation as a reservoir of multidrug-resistant enterococci in a metropolitan area in Brazil.","authors":"Andrea de Andrade Rangel Freitas, Adriana Rocha Faria, Luiza Tomé Mendes, Vânia Lúcia Carreira Merquior, Daniel Marchesi Neves, Jeferson Rocha Pires, Lúcia Martins Teixeira","doi":"10.1007/s42770-024-01527-3","DOIUrl":"10.1007/s42770-024-01527-3","url":null,"abstract":"<p><p>Enterococci are ubiquitous usually commensal bacteria that can act as opportunistic pathogens frequently associated with resistance to multiple antimicrobial classes. A variety of animals may carry potentially harmful enterococci. In the present work, the occurrence and characteristics of enterococci recovered from the fecal microbiota of wild birds belonging to four families (Accipitridae, Cathartidae, Falconidae and Strigidae) were investigated. Enterococci were recovered from 104 (92.0%) fecal samples obtained from 113 birds, and 260 strains were selected for additional characterization. Enterococcus faecalis was the predominant species (63.8%), followed by Enterococcus hirae (16.2%), Enterococcus faecium (11.5%), Enterococcus gallinarum (5.4%), Enterococcus avium (1.5%), Enterococcus casseliflavus (0.8%), and Enterococcus raffinosus and Enterococcus cecorum (0.4% each). Major percentages (11.9% 75.0%) of nonsusceptibility were observed to quinolones (particularly to enrofloxacin), erythromycin, rifampin, nitrofurantoin, tetracycline and streptomycin. Gentamicin and ampicillin resistances (13.3% each) were only detected among E. faecium. A total of 133 (51.2%) strains were MDR, showing a large variety of MDR profiles, composed by simultaneous resistance encompassing 3 to 12 antimicrobials. MDR strains were found in 68.2% of the birds. Antimicrobial resistance was associated with the presence of the aac(6')-aph(2″)-Ia, aph(2″)-Id, ant(6)-Ia, ant(9)-Ia, ant(9)-Ib, tet(M), tet(L), tet(S), erm(B), mef(A/E), msrC, and vat(D) genes. The most common virulence genes were efaA, gelE, ace, eeP, and asa1. PFGE analysis revealed a large genetic diversity among most of the strains. MLST performed for 35 E. faecalis strains revealed 23 different STs, whereas 14 STs were found among 18 E. faecium strains. Hospital-associated lineages ST22, ST25, ST56, ST1274 were identified. The results show that the wild birds investigated can carry a diversity of potentially hazardous enterococcal strains displaying multiple antimicrobial resistance and virulence genes, reinforcing the assumption that these animals provide an important target to monitor the circulation of microorganisms that deserve consideration under the One Health perspective.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":" ","pages":"3849-3861"},"PeriodicalIF":2.1,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11711916/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142360998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of the anti-Candida activity of tricyclic antidepressants in association with amphotericin B and their antifungal mechanisms.","authors":"Vitória Pessoa de Farias Cabral, Daniel Sampaio Rodrigues, Lívia Gurgel do Amaral Valente Sá, Lara Elloyse Almeida Moreira, Cecília Rocha da Silva, João Batista de Andrade Neto, Érica Rayanne Mota da Costa, Thais Lima Ferreira, Leilson Carvalho de Oliveira, Beatriz Oliveira de Souza, Bruno Coêlho Cavalcanti, Islay Lima Magalhães, Manoel Odorico de Moraes, Hélio Vitoriano Nobre Júnior","doi":"10.1007/s42770-024-01459-y","DOIUrl":"10.1007/s42770-024-01459-y","url":null,"abstract":"<p><p>Candida species are among the priority pathogens in the area of research and development. Due to the problems associated with resistance to antifungals, new therapeutic alternatives are necessary. In this regard, drug repositioning has gained prominence. The objective of this study was to evaluate the activity of three tricyclic antidepressants (TCAs) - amitriptyline (AMT), nortriptyline (NOR) and clomipramine (CLO) - isolated or associated with antifungals against strains of Candida spp., as well as to analyze the possible mechanism of action. Among the methods used were broth microdilution tests, tolerance level assessment, checkerboard assays, flow cytometry and fluorescence microscopy. Furthermore, Candida cells were visualized after treatments by scanning electron microscopy (SEM). AMT presented MIC 50% in the range of 16 to 128 µg/mL, NOR from 8 to 128 µg/mL, and CLO from 8 to 64 µg/mL, with all three TCAs having a fungicidal inhibitory action profile. For these TCAs, there was synergism with amphotericin B (AMB) in 100% of the isolates. In association with fluconazole (FLC) and itraconazole (ITR), there were mostly indifferent interactions. TCAs isolated and associated with AMB reduced cell viability, promoted DNA fragmentation and damage, caused mitochondrial depolarization, externalization of phosphatidylserine, produced reactive oxygen species (ROS), decreased reduced glutathione (GSH) and increased carbonyl protein levels, causing morphological changes. The results suggest the antifungal mechanism of the TCAs works via the apoptotic pathway.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":" ","pages":"3617-3628"},"PeriodicalIF":2.1,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11711746/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142092185","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A double ttrA and pduA knock-out mutant of Salmonella Typhimurium is not attenuated for mice (Mus musculus).","authors":"Viviane Amorim Ferreira, Mauro M S Saraiva, Túlio Spina de Lima, Camila de Fátima Nascimento, Giovanna Barbosa Casagrande Paschone, André L C Rabelo, Adriana M Almeida, Oliveiro C Freitas Neto, Paul A Barrow, Angelo Berchieri Junior","doi":"10.1007/s42770-024-01533-5","DOIUrl":"10.1007/s42770-024-01533-5","url":null,"abstract":"<p><p>Despite numerous studies on Salmonella enterica subsp. enterica serovar Typhimurium, the underlying mechanisms of several aspects of its virulence are still under investigation, including the role of the pdu and ttrA genes, associated with the metabolism of 1,2-propanediol using tetrathionate as an electron acceptor respectively. Our objective was to contribute to an understanding of the role of these genes inbacterial virulence for mice (Mus musculus) using an S. Typhumirum ΔttrApduA mutant. The experiment was conducted with a group infected by the S. Typhimurium mutant and a control group infected with a wild-type strain. The mutant was not attenuated compared with the parent strain. There were no differences in the bacterial numbers recovered from the mesenteric lymph nodes and Peyer's patches but at 8-day after oral infection higher numbers were recovered from the spleen, liver, and cecum. Unlike the single pduA and ttrA mutants, the double ΔttrApduA mutation did not affect invasion and survival in mice, which highlights the need for further studies to clarify the role of these important metabolism genes under reduced redox conditions linked to Salmonella virulence.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":" ","pages":"4177-4182"},"PeriodicalIF":2.1,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11711602/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142457833","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of simulated low-temperature thermal remediation on the microbial community of a tropical creosote contaminated soil.","authors":"Daniel Di Pace Soares Penna, Valéria Maia Merzel, Juliana Gardenalli de Freitas, Kelly Johanna Hidalgo Martinez, Alexandre Muselli Barbosa, Cristina Rossi Nakayama","doi":"10.1007/s42770-024-01541-5","DOIUrl":"10.1007/s42770-024-01541-5","url":null,"abstract":"<p><p>In the search for more sustainable remediation strategies for PAH-contaminated soils, an integrated application of thermal remediation and bioremediation (TEB) may allow the use of less impacting temperatures by associating heating to biological degradation. However, the influence of heating on soil microbiota remains poorly understood, especially in soils from tropical regions. This work investigated the effects of low-temperature heating on creosote-contaminated soil bacteria. We used culture-dependent and 16 S rRNA sequencing methods to compare the microbial community of soil samples heated to 60 and 100 ^oC for 1 h in microcosms. Heating to 60 °C reduced the density of cultivable heterotrophic bacteria compared to control soil (p < 0.05), and exposure to 100 °C inactivated the viable heterotrophic community. Burkholderia-Caballeronia-Paraburkholderia (BCP) group and Sphingobium were the predominant genera. Temperature and incubation time affected the Bray-Curtis dissimilarity index (p < 0.05). At 60 °C and 30 days incubation, the relative abundance of Sphingobium decreased and BCP increased dominance. The network of heated soil after 30 days of incubation showed fewer nodes and edges but maintained its density and complexity. Both main genera are associated with PAH degradation, suggesting functional redundancy and a likely potential of soil microbiota to maintain biodegradation ability after exposure to higher temperatures. We concluded that TEB can be considered as a potential strategy to bioremediate creosote-contaminated soils, allowing biodegradation in temperature ranges where thermal remediation does not completely remove contaminants. However, we recommend further research to determine degradation rates with this technology.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":" ","pages":"3413-3424"},"PeriodicalIF":2.1,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11711421/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142457837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"CRISPR-Cas systems in enterococci.","authors":"Amanda Seabra Cabral, Fernanda de Freitas Lacerda, Vitor Luis Macena Leite, Filipe Martire de Miranda, Amanda Beiral da Silva, Bárbara Araújo Dos Santos, Jailton Lobo da Costa Lima, Lúcia Martins Teixeira, Felipe Piedade Gonçalves Neves","doi":"10.1007/s42770-024-01549-x","DOIUrl":"10.1007/s42770-024-01549-x","url":null,"abstract":"<p><p>Enterococci are members of the microbiota of humans and other animals. They can also be found in the environment, associated with food, healthcare infections, and hospital settings. Due to their wide distribution, they are inserted in the One Health context. The selective pressure caused by the extensive use of antimicrobial agents in humans, animals, and agriculture has increased the frequency of resistance to various drugs among enterococcal species. CRISPR-Cas system, an important prokaryotic defense mechanism against the entry of mobile genetic elements, may prevent the acquisition of genes involved in antimicrobial resistance and virulence. This system has been increasingly used as a gene editing tool, which can be used as a way to recognize and inactivate genes of interest. Here, we conduct a review on CRISPR systems found in enterococci, considering their occurrence, structure and organization, mechanisms of action and use as a genetic engineering technology. Type II-A CRISPR-Cas systems were shown to be the most frequent among enterococcal species, and the orphan CRISPR2 was the most commonly found system (54.1%) among enterococcal species, especially in Enterococcus faecalis. Distribution of CRISPR systems varied among species. CRISPR systems had 1 to 20 spacers, with size between 23 and 37 bp and direct repeat sequences from 25 to 37 bp. Several applications of the CRISPR-Cas biotechnology have been described in enterococci, mostly in vitro, using this editing tool to target resistance- and virulence-related genes.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":" ","pages":"3945-3957"},"PeriodicalIF":2.1,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11711564/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142494962","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First report on genetic characterization of egg drop syndrome 1976 virus in Egypt.","authors":"Emad Al-Ebshahy, Mohammed AboElkhair, Awad Shehata, Emad Elgendy","doi":"10.1007/s42770-024-01537-1","DOIUrl":"10.1007/s42770-024-01537-1","url":null,"abstract":"<p><p>Since its first description in 1991 in Egypt, egg drop syndrome 1976 (EDS-76) virus has received a little attention as a potential cause for the drop in egg production as well as the reduction in egg quality. To date, no studies have been carried out to describe the genetic characteristics of the circulating field EDS-76 virus strains. Thus, the present study was attempted to estimate the emergence of EDS-76 virus in layer flocks and to determine the genetic diversity between the field strains and the vaccine strain 127. During 2022, a total of 5 apparently healthy backyard layer flocks were investigated for the presence of EDS-76 virus infection following complaints of sudden drop in egg production (25-30%), accompanied by high incidence of eggshell defects. EDS-76 virus DNA was detected in the oviduct samples of 4 (80%) flocks by polymerase chain reaction (PCR) assay targeting the hexon gene of the viral capsid. Attempts of viral isolation in duck embryo revealed no embryonic mortality, however, the allantoic fluids of inoculated eggs exhibited a sustained increase in the hemagglutinating (HA) activity throughout three consecutive passages. The obtained strain, designated BH-1, was characterized on the basis of partial hexon gene sequence analysis (GenBank accession number OR531368). The BH-1 strain displayed 99.6% nucleotide identity with the vaccine strain 127. However, amino acid alignments with the vaccine strain 127 revealed that the BH-1 strain carried 5 non-synonymous mutations. In addition, two of these mutations were incorporated into the hexon hypervariable regions (HVRs), which are strictly responsible for eliciting serotype-specific neutralizing antibodies. In conclusion, the present study represents a starting point for genetic characterization of EDS-76 virus in Egypt and highlights the importance for continuous monitoring and characterization of the circulating field EDS-76 virus strains, in order to determine the proper control strategy.</p>","PeriodicalId":9090,"journal":{"name":"Brazilian Journal of Microbiology","volume":" ","pages":"4199-4204"},"PeriodicalIF":2.1,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11711557/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142494964","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}