Microbiology Research最新文献

{"title":"In Vitro Cytotoxicity and Hemolysis Effect of Poly-Gamma-Glutamic Acid Nano-Polymer Biosynthesized Using Some Isolates of Bacillus spp.","authors":"Eman M. Elsayed, Ahmed A. Farghali, Mohamed I. Zanaty, Medhat Abdel-Fattah, Dalal Hussien M. Alkhalifah, Wael N. Hozzein, Ahmed M. Mahmoud","doi":"10.3390/microbiolres14040118","DOIUrl":"https://doi.org/10.3390/microbiolres14040118","url":null,"abstract":"Natural polymers have good biological, biocompatible properties and a low degradation rate, so they can be used in medical applications. This study demonstrates an optimized biosynthesis for poly-gamma-glutamic acid nano-polymer (ɣ-PGA NP) using three bacterial isolates encoded as B4, B5, and B6. The 16S rRNA gene sequence of the isolates showed 98.5, 99, and 99.8% similarity with Bacillus sp., with accession numbers MZ976778, MZ976779, and MZ956153, respectively. The optimal conditions of the biosynthesis were 35 °C, followed by incubation for 30 h, 7 pH, 0.7 O.D600 of bacterial broth, carbon sources of glutamic acid and glucose, and ammonium sulfate as the nitrogen source. Biosynthesized ɣ-PGA NPs were characterized using X-ray diffraction (XRD), Zeta sizer, Fourier transform infrared (FT-IR), transmission electron microscopy (TEM), and nuclear magnetic resonance (1HNMR). The TEM study showed the formation of oval-shaped ɣ-PGA NPs with sizes 31.75–32.69 nm, 18.63–21.66 nm, and 37.57–39.22 nm for B4, B5, and B6, respectively. XRD, FT-IR, and 1HNMR confirmed the purity of the polymer. The hemolysis rates of the biosynthesized ɣ-PGA NPs were below the acceptable value. Moreover, the cytotoxicity test conducted using an MTT assay on peripheral blood mononuclear cells (PBMCs) revealed no significant effect on the cell viability within a dose range of up to 512 μg/mL.","PeriodicalId":43788,"journal":{"name":"Microbiology Research","volume":"40 6","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136135712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Short-Term PE Generation Processes in the Soils of a Farmer Plots Network in the Madagascar Highlands: Actors and Drivers","authors":"Kanto Razanamalala, Tantely Razafimbelo, Pierre-Alain Maron, Lionel Ranjard, Nicolas Chemidlin Prévost-Bouré, Samuel Dequiedt, Thierry Becquer, Jean Trap, Eric Blanchart, Laetitia Bernard","doi":"10.3390/microbiolres14040117","DOIUrl":"https://doi.org/10.3390/microbiolres14040117","url":null,"abstract":"Carbon sequestration in agricultural soils, through the accumulation of high-quality organic matter, represents great potential to mitigate climate change and simultaneously improve soil fertility. Such a challenge is particularly important and relevant in developing tropical countries like Madagascar, where soil carbon storage is vulnerable to climatic variations and where fertilization is generally applied through amendments in organic matter of various origins. The priming effect (PE) is considered here as the stimulation of the mineralization of soil organic matter (SOM) by a supply of fresh organic matter (FOM). PE results from different microbial processes driven by specific biotic and abiotic parameters. Depending on the processes involved, it has been suggested that PE could either counteract SOM accumulation or promote it. The objective of the present study was to explore the relationships between certain agricultural practices (type of crop, quality of fertilization, association with trees), the potential intensity of PE, as well as several abiotic (texture, quantity and quality SOM, nutrient enrichment) a1nd biotic (biomass and phylogenetic composition of microbial communities) factors which have been proposed in the literature as specific determinants of the different PE generation mechanisms. The soils for this study come from a network of farms in a commune in the Highlands of Madagascar. The PE, generated by a supply of 13C-enriched wheat straw, could not directly correlate with agricultural treatments. However, several indirect correlations could be found via several specific abiotic and microbial determinants that are discussed in terms of soil fertility restoration.","PeriodicalId":43788,"journal":{"name":"Microbiology Research","volume":"38 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136262979","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of Predicted siRNA as an Antiviral against MERS-CoV Targeting the Membrane Gene in the Vero Cell Line","authors":"Amany Y. El-Sayed, Mahmoud Shehata, Sara H. Mahmoud, Mahmoud ElHefnawi, Dina M. Seoudi, Mohamed A. Ali","doi":"10.3390/microbiolres14040116","DOIUrl":"https://doi.org/10.3390/microbiolres14040116","url":null,"abstract":"The Middle East respiratory syndrome coronavirus (MERS-CoV) was first isolated from a patient with acute pneumonia and renal failure in Saudi Arabia in 2012. By July 2023, MERS-CoV had resulted in 2605 human cases worldwide, causing a fatality rate of 36%, with 90.2% of cases being located in the Arabian Peninsula. The dromedary camel (Camelus dromedarius) is presumed to be an intermediate host for viral transmission to humans. So far, no prophylactic vaccines or effective antiviral treatments have been approved for MERS-CoV. RNA silencing is a novel approach for treating several diseases. A web-based bioinformatics tool (i-Score Designer) with integrative computational methods was used to predict and evaluate the designed siRNAs. This approach enabled the targeting of a highly conserved region of the MERS-CoV membrane (M) gene to inhibit virus replication. siRNA-M1, -M2, and -M3 were selected as the best of 559 designed siRNA candidates for an in vitro validation based on 2nd generation algorithm scoring, thermodynamic properties, off-target filtration, position-specific nucleotide preferences, and a free immune-stimulatory motifs. siRNAs were evaluated in Vero cells for their cytotoxicity and antiviral efficacy in vitro. Our results showed that the predicted siRNAs had no apparent cytotoxicity observed in Vero cells. The obtained results from the plaque reduction assay and RT-qPCR indicated that siRNA-M3 was the best candidate to inhibit MERS-CoV replication with a defined concentration of 400 picoMolar (pM). The computational methods used, and the in vitro evaluation, may provide an insight for a new antiviral strategy against MERS-CoV, a further in vivo study will nevertheless be required.","PeriodicalId":43788,"journal":{"name":"Microbiology Research","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136033425","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Serum Level of Ceruloplasmin, Angiotensin-Converting Enzyme and Transferrin as Markers of Severity in SARS-CoV-2 Infection in Patients with Type 2 Diabetes","authors":"Patricia-Andrada Reștea, Ștefan Țigan, Laura Grațiela Vicaș, Luminița Fritea, Eleonora Marian, Tunde Jurca, Annamaria Pallag, Iulius Liviu Mureșan, Corina Moisa, Otilia Micle, Mariana Eugenia Mureșan","doi":"10.3390/microbiolres14040115","DOIUrl":"https://doi.org/10.3390/microbiolres14040115","url":null,"abstract":"The aim of this study was to analyze other possible new markers of severity, at hospital admission, that can be assessed in patients with type 2 diabetes and a SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) infection. Our study included 90 subjects: 45 patients with type 2 diabetes mellitus infected with the SARS-CoV-2 virus, and 45 healthy persons as controls. The serum level of ceruloplasmin at hospital admission was statistically significant and directly correlated with the severity of COVID-19 (coronavirus disease) (p = 0.037) and with the serum level of IL-6 (interleukin 6) (p = 0.0001). Ceruloplasmin was statistically significant and inversely correlated with the serum iron level (p = 0.0001). However, we observed that ACE (angiotensin-converting enzyme) decreased in severe forms of SARS-CoV-2 infections in patients with type 2 diabetes (p = 0.001). Moreover, the decrease in ACE levels was correlated with an increase in IL-6 levels in these patients (p = 0.001). IL-6 increases were statistically significant and inversely correlated with serum iron, transferrin, and ACE levels. There was a noticed decreasing tendency of the transferrin depending on the severity of the COVID-19 infection (p = 0.0001). In addition to the known severity factors in the context of infection with the new coronavirus, increased concentrations of ceruloplasmin and decreased concentrations of ACE and transferrin may represent new markers of COVID-19 severity in patients with type 2 diabetes. These parameters, if analyzed upon admission to the hospital, could better inform health professionals about the evolution towards more severe forms of SARS-CoV-2 infections.","PeriodicalId":43788,"journal":{"name":"Microbiology Research","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136115171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Control of Biofilm and Virulence in Pseudomonas aeruginosa by Green-Synthesized Titanium–Cerium Nanocomposites","authors":"Mohammad Altaf, Nagma Parveen, Faizan Abul Qais, K. M. Abdullah, Iqbal Ahmad","doi":"10.3390/microbiolres14040114","DOIUrl":"https://doi.org/10.3390/microbiolres14040114","url":null,"abstract":"Antimicrobial resistance (AMR) has become a critical global health challenge. Infections, particularly those caused by multidrug-resistant (MDR) pathogens, rank among the top causes of human mortality worldwide. Pseudomonas aeruginosa occupies a prominent position among pathogens responsible for opportunistic infections in humans. P. aeruginosa stands as a primary cause of chronic respiratory infections, significantly contributing to the burden of these chronic diseases. In the medical domain, nanotechnologies offer significant potential, spanning various applications, including advanced imaging, diagnostic devices, drug delivery systems, implants, tissue-engineered structures, and pharmaceutical treatments. Given the challenges associated with AMR and the limited discovery of new drugs to combat MDR microbes, there is a critical need for alternative strategies to address the problem of AMR. In this study, we synthesized titanium–cerium nanocomposites (Ti–Ce–NCs) using an eco-friendly green synthesis approach. X-ray diffraction (XRD) analysis confirmed the crystalline nature of the Ti–Ce–NCs and determined the particle size to be 17.07 nm. Electron microscopy revealed the size range of the particles to be 13 to 54 nm, where the majority of the particles were in the 20 to 25 nm range. Upon examining the composition, the Ti–Ce–NCs were determined to be composed of cerium, oxygen, and titanium, whose relative abundance were 36.86, 36.6, and 24.77% by weight, respectively. These nanocomposites were then evaluated for their effectiveness against various virulent traits and biofilms in P. aeruginosa. Out of six tested virulence factors, more than 50% inhibition of five virulence factors of P. aeruginosa was found. Roughly 60% inhibition of biofilm was also found in the presence of 400 µg/mL Ti–Ce–NCs. The nanocomposites also altered the biofilm architecture of the test bacterium. The success of this research opens doors for the potential use of such nanomaterials in the discovery of new antibacterial agents to combat drug-resistant bacteria.","PeriodicalId":43788,"journal":{"name":"Microbiology Research","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135855853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Strategies to Develop Aptamer Probes to Detect MRSA and Study of Antibacterial Activity","authors":"Jagath C. Kasturiarachchi","doi":"10.3390/microbiolres14040112","DOIUrl":"https://doi.org/10.3390/microbiolres14040112","url":null,"abstract":"This study investigated the development of aptamer-based molecular probes to detect Methicillin-Resistant Staphylococcus aureus (MRSA) and evaluated the antibacterial activity. Early detection of MRSA infection will improve patients’ recovery and reduce the cost for treating patients. S. aureus can become resistant to methicillin and other β-lactam antibiotics through the expression of PBP2A protein, which is resistant to the action of methicillin. We have developed two aptamer molecular probes against PBP2A protein and whole bacterial cell (MRSA) under optimized in vitro conditions using SELEX approach. Target aptamer sequences were identified, and chemically synthesized aptamer probes were evaluated using fluorescently-labelled aptamer probes using flow cytometry and confocal imaging. Antibacterial activities of those aptamers were also evaluated using a bacterial killing assay. The results showed that high specific aptamers were developed against purified PBP2A protein. However, these aptamers showed less specificity to detect MRSA under in vitro condition. These aptamers showed no cytotoxic effect on 3T3 cells and no antibacterial activity against MRSA. The results suggested that the specific aptamer development and the in vitro selection methodology require further refinement to improve the diagnostic and therapeutic utility of these aptamers.","PeriodicalId":43788,"journal":{"name":"Microbiology Research","volume":"125 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135918837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Grass Meal Acts as a Probiotic in Chicken","authors":"Elena S. Bogdanova, Maria A. Danilova, Maria S. Smirnova, Elena V. Trubnikova, Hoa T. Nguyen, Svetlana N. Petrova, Sergey V. Apanasenok, Alexei B. Shevelev","doi":"10.3390/microbiolres14040113","DOIUrl":"https://doi.org/10.3390/microbiolres14040113","url":null,"abstract":"Probiotics can act as an alternative to antibiotics in animal feeding, but their use is minimal due to their expensive production. Dry grass is rich with bacteria beneficial for animal feeding and can be used as a probiotic. However, data about the quantitative dependence of the grass microbiome on environmental factors and seasons remain insufficient for preparing “grass-meal-based probiotics”. Four grass samples were collected in two geographically remote regions of Russia; their microbiome was characterized by metagenomic sequencing of 16S rDNA libraries and microbiological seeding, and biological testing of the grass meal was carried out on 6 groups of birds containing 20 Ross 308 cross broilers each for a period of 42 days. The positive control group (PC) obtained 16–25 mg/mL toltrazuril (coccidiostatic agent) and 0.5 mL/L liquid antibiotic enrostin (100 mg/mL ciprofloxacin and 106 MU/mL colistin sulfate in the commercial preparation) within the drinking water, while the negative control group (NC) obtained no medicines. Four experimental groups were fed the diet supplemented with 1% grass meal over the period of 7–42 days of life; no commercial medicines were used here. A spontaneous infection with Eimeria was registered in the NC control groups, which caused the loss of 7 chickens. No losses were registered in the PC group or the two experimental groups. In two other experimental groups, losses of coccidiosis amounted to 10% and 15%, respectively. All specimens of the grass meal demonstrated a significant effect on the average body weight gain compared to NC. Taken together, these observations support the hypothesis that the grass meal may substitute toltrazuril for protecting the chickens from parasitic invasion and increase average daily weight gain (ADG) as effectively as the antibiotic enrostin.","PeriodicalId":43788,"journal":{"name":"Microbiology Research","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135918090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bacterial Co-Infection in Patients with Coronavirus: A Rapid Review to Support COVID-19 Antimicrobial Prescription","authors":"María Fernanda Celaya Corella, Jorge Omer Rodeles Nieblas, Donato Antonio Rechy Iruretagoyena, Gerson Ney Hernández Acevedo","doi":"10.3390/microbiolres14040111","DOIUrl":"https://doi.org/10.3390/microbiolres14040111","url":null,"abstract":"The goal of this study was to determine the most common microorganisms present in COVID-19 patients with co-infections at the General Hospital of Mexicali. Bacterial co-infections have been reported in two previous global pandemics caused by viruses. In a retrospective observational study, we obtained information from 1979 patients. All had symptoms of respiratory disease, and we performed real-time Polymerase Chain Reaction tests on nasopharyngeal swab samples. Of the 1979 patients, 316 were negative; so, they were excluded. One thousand and sixty-three patients had positive results for COVID-19; one hundred and seventy-two (10.34%) had respiratory co-infections. These data were corroborated by positive growth results in culture media and identified using the MALDI-TOF MS System. Vitek 2® Compact, an automated identification system, determined the antimicrobial susceptibility testing results. We analyzed and determined the microorganisms in co-infected patients. Different microorganisms were found, including bacteria and fungi. The most prevalent of all the organisms was Acinetobacter baumannii, which was present in 64 patients (37.2%). We recommend improving the diagnostic and surveillance protocols for possible cases of co-infections in patients with COVID-19. Unlike co-infections in pandemic influenza, the spectrum of microorganisms that cause COVID-19 is too broad and varied to recommend empiric antibiotic therapy.","PeriodicalId":43788,"journal":{"name":"Microbiology Research","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136097798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Studying the Anti-Virulence Activity of Meta-Bromo-Thiolactone against Staphylococcus aureus and MRSA Phenotypes","authors":"Rihaf Alfaraj, Esra K. Eltayb, Bashayer M. AlFayez, Amjad Abohamad, Eram Eltahir, Naifa A. Alenazi, Sandra Hababah, Hamad Alkahtani, Thamer A. Almangour, Fulwah Y. Alqahtani, Fadilah S. Aleanizy","doi":"10.3390/microbiolres14040110","DOIUrl":"https://doi.org/10.3390/microbiolres14040110","url":null,"abstract":"Quorum-sensing inhibitors have recently garnered great interest, as they reduce bacterial virulence, lower the probability of resistance, and inhibit infections. In this work, meta-bromo-thiolactone (mBTL), a potent quorum and virulence inhibitor of Staphylococcus aureus (S. aureus) and methicillin-resistant S. aureus (MRSA), was formulated in chitosan nanoparticles (ChNPs) using the ionic gelation method. The mBTL-loaded-ChNPs were characterized by their particle size, polydispersity index, zeta potential, morphology, and drug release profile. The results show that the mBTL-loaded-CNPs comprised homogenized, spherical nanoparticles ranging from 158 ± 1.3 to 284 ± 5.6 nm with a sustainable release profile over 48 h at 37 °C. These findings confirm the successful preparation of mBTL-loaded-ChNPs. Confocal laser scanning microscopy showed a significant reduction in the number of viable cells, indicating the antibacterial efficacy of mBTL. Biofilms were observed by scanning electron microscopy, which showed that the bacterial cells in the control experiment were enclosed in thick biofilms. In the presence of mBTL, the bacterial cells remained disordered and did not form a biofilm. mBTL-loaded-ChNPs represent a potential approach to overcoming antimicrobial resistance in the treatment of MRSA infection.","PeriodicalId":43788,"journal":{"name":"Microbiology Research","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136358350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Q Fever in Unexplained Febrile Illness in Northern Algeria","authors":"H. Ghaoui, N. Achour, A. Saad-Djaballah, S. I. Belacel, I. Bitam, P. E. Fournier","doi":"10.3390/microbiolres14040109","DOIUrl":"https://doi.org/10.3390/microbiolres14040109","url":null,"abstract":"Our study aimed at assessing the role of Coxiella burnetii in nonspecific febrile illness at the National Center of Infectious Diseases in Algeria, EL-HADI FLICI Hospital. Seventy patients were included and compared to seventy controls without any ongoing infection. Coxiella burnetii infection was investigated using IFA serology and qPCR. Serology was positive in 3 of 70 patients (4.30%), including 1 in whom PCR was also positive (1.42%). All three patients reported frequent contact with ruminants. These results suggest that C. burnetii is an agent of nonspecific febrile illness in Algeria.","PeriodicalId":43788,"journal":{"name":"Microbiology Research","volume":"116 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135094303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}