Folia microbiologica最新文献

{"title":"Enhancement of carotenogenesis by Blakeslea trispora in a mixed culture with bacteria.","authors":"Maryam Azizi, Davood Zare, Abbas Akhavan Sepahi, Mehrdad Azin","doi":"10.1007/s12223-024-01202-y","DOIUrl":"10.1007/s12223-024-01202-y","url":null,"abstract":"<p><p>Among carotenoids, ꞵ-carotene has the highest biological activity and is found as an all-trans isomer in many biological systems. Blakeslea trispora is a microorganism that is of interest to industries for the commercial production of ꞵ-carotene. This study investigated the effect of different bacteria on carotenogenesis in B. trispora. The B. trispora bisexual mold was cultured in a production medium, and different bacterial cells were added to it after 24 h. Then, the culture conditions and the culture medium were optimized in the presence of the selected bacteria using the experimental design. The percentage of carotenoids obtained from the mixed culture was determined using high-performance liquid chromatography (HPLC). Results showed that Kocuria rhizophila had the greatest effect on increasing the production of carotenoids in B. trispora. The highest content of carotenoids obtained during optimization was 770 ± 7.5 mg/L, a 6.8-fold increase compared to the control. HPLC analysis of carotenoids indicated the presence of two main peaks, ꞵ-carotene and ^γ-carotene, in which the primary carotenoid was ꞵ-carotene followed by ^γ-carotene with a lower content. Therefore, due to the importance of ꞵ-carotene in industry, the use of biostimulants is one of the appropriate strategies to increase the production of this pigment in industry.</p>","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":"545-557"},"PeriodicalIF":2.4,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142364983","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":"Applicability of Cyclotella caspia and Thalassiosira weissflogii diatomous water growth for the removal of the antibiotic tetracycline.","authors":"Ekaterina S Solomonova, Natalia Yu Shoman, Arkady I Akimov","doi":"10.1007/s12223-025-01255-7","DOIUrl":"10.1007/s12223-025-01255-7","url":null,"abstract":"<p><p>The effect of the antibiotic tetracycline on the growth and photosynthetic activity of the diatoms Cyclotella caspia Grunow, 1878, and Thalassiosira weissflogii (Grunow) G.A. Fryxell & Hasle, 1977, has been studied. The rate of tetracycline concentration decreases in the medium with and without has been estimated. The expediency and prospects of using diatoms as promising objects for water purification from tetracycline are shown. It was found that the rate and efficiency of tetracycline removal from the medium in the presence of algae depends on the initial content of the pollutant in the medium. The maximum efficiency of antibiotic removal is observed at concentrations of the pollutant provoking the hormesis growth of algae at 5 mg/L in C. caspia and 10 mg/L in T. weissflogii. In samples with C. caspia and tetracycline, the residual antibiotic content in the medium was 10-14% lower than in samples without algae. In the experiment with T. weissflogii, this indicator reached 15-16%. At concentrations of the pollutant, 2 and 10 mg/L in C. caspia and 2 and 5 mg/L in T. weissflogii, the effectiveness of removing the antibiotic by algae was lower. The residual content of tetracycline in the medium was on average 8-11% lower than in samples without algae. At antibiotic concentrations of 15 and 20 mg/L, the rate of its removal in samples with and without algae did not significantly differ. This result is obviously due to the toxic effect of tetracycline on cells, leading to pronounced inhibition of algae growth and/or death.</p>","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":"657-663"},"PeriodicalIF":2.4,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143633865","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":"Bio sulfur granules developed with Methylobacterium thiocyanatum promoted black gram growth and yield in sulfur-deficient calcareous vertisol.","authors":"G Akila, S Thiyageshwari, R Krishnamoorthy, D Selvi, A Manikandan, R Anandham, M Djanaguirman","doi":"10.1007/s12223-024-01199-4","DOIUrl":"10.1007/s12223-024-01199-4","url":null,"abstract":"<p><p>High soil pH and excess CaCO₃ are major contributors to calcareous soil limitations on crops' access to essential nutrients, especially phosphorus (P) and micronutrients, which in turn impact pulses yields and growth. The purpose of this study was to determine the effect of bio sulfur granules (BSG) on the growth of black gram and the availability of nutrients in calcareous vertisols deficient in sulfur. BSG was developed by using sulfur-oxidizing bacteria (SOB) and elemental sulfur (ES) through an incubation study. Developed BSG was tested in a pot and field conditions to evaluate their effectiveness on black gram growth and yield. In the incubation study, soil treated with Methylobacterium thiocyanatum VRI7-A4 and ES (40 kg S/ha) significantly decreased pH and increased available S (SO₄^2-) in calcareous soils. After 40 days of incubation, the solubility of P, Fe, and Zn was greatly increased by the addition of ES @ 40 kg S/ ha in combination with M. thiocyanatum VRI7-A4 or Pandoraea thiooxydans ATSB16. Black gram in S-deficient calcareous soil was improved by the application of BSG (ES @ 40 kg S/ ha with M. thiocyanatum VRI7-A7) in terms of root and shoot lengths, nodule number, plant biomass, pod yield, and biological yield as compared to control. The same treatment greatly increased plant nutrient intake as well as the concentrations of P, Fe, and Zn in the soil. The results showed that the addition of BSG granules (ES @ 40 kg S/ha + M. thiocyanatum VRI7-A4) to calcareous vertisol deficient in S enhanced the nutrient solubility through S oxidation. The developed bio sulfur granules may be added to the fertilizer schedule of the pulses growers to get improved crop growth and yield of black gram in calcareous soil.</p>","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":"559-574"},"PeriodicalIF":2.4,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142377839","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":"Effect of rhizosphere soil microbial communities and environmental factors on growth and the active ingredients of Angelica sinensis in Gansu Province, China.","authors":"Zuhua Yan, Hui Jin, Xiaoyan Yang, Deng Min, Xinxin Xu, Cuiping Hua, Bo Qin","doi":"10.1007/s12223-024-01210-y","DOIUrl":"10.1007/s12223-024-01210-y","url":null,"abstract":"<p><p>The growth and accumulation of active ingredients of Angelica sinensis were affected by rhizosphere soil microbial communities and soil environmental factors. However, the correlationship between growth and active ingredients and soil biotic and abiotic factors is still unclear. This study explored rhizosphere soil microbial community structures, soil physicochemical properties, enzyme activities, and their effects on the growth and active ingredient contents of A. sinensis in three principal cropping areas. Results indicated that the growth indices, ligustilide, ferulic acid contents, and soil environmental factors varied in cropping areas. Pearson correlation analysis revealed that the growth of A. sinensis was affected by organic matter, total nitrogen, total phosphorus, and available phosphorus; ferulic acid and ligustilide accumulation were related to soil catalase and alkaline phosphatase activities, respectively. Illumina MiSeq sequencing showed that the genera Mortierella and Conocybe were the dominant fungal communities, and Sphingomonas, Pseudomonas, Bryobacter, and Lysobacter were the main bacterial communities associated with the rhizosphere soil. Kruskal-Wallis one-way ANOVA and Spearman correlation conjoint analysis demonstrated a significant positive correlation (p < 0.001) among the composition of the rhizosphere microbial communities at all three sampling sites. The growth and active ingredient accumulation of A. sinensis not only was significantly susceptible to the bacterial communities of Sphingomonas, Epicoccum, Marivita, Muribaculum, and Gemmatimonas but also were significantly influenced by the fungal communities of Inocybe, Septoria, Tetracladium, and Mortierella (p < 0.05). Our findings provide a scientific basis for understanding the relationship between the growth and active ingredients in A. sinensis and their corresponding rhizosphere soil microbial communities, soil physicochemical properties, and enzyme activities.</p>","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":"673-687"},"PeriodicalIF":2.4,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142544664","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":"Characterizing the interplay between Acinetobacter baumannii, A549 cells, and anti-Omp34 antibodies: implications for adherence, internalization, and cytotoxicity.","authors":"Masoomeh Rajabzadeh, Zahra Fekrirad, Mohammadreza Jalali Nadoushan, Iraj Rasooli","doi":"10.1007/s12223-024-01218-4","DOIUrl":"10.1007/s12223-024-01218-4","url":null,"abstract":"<p><p>Acinetobacter baumannii thrives within eukaryotic cells, influencing persistence, treatment approaches, and progression of disease. We probed epithelial cell invasion by A. baumannii and the influence of antibodies raised to outer membrane protein 34 (Omp34) on epithelial interactions. We expressed and purified recombinant Omp34 and induced anti-Omp34 antibodies in Bagg albino or BALB/c mice. Omp34 was evaluated for acute toxicity in mice through histological analysis of six organs. The host cell line, A549, was exposed to both A. baumannii 19606 and a clinical isolate. The study also investigated serum resistance, adherence, internalization, and proliferation of A. baumannii in A549 cells, with and without anti-Omp34 sera, utilizing cell culture techniques and light microscopy. A549 cell viability was evaluated by A. baumannii challenge and exposure to anti-Omp34 sera. Actin disruption experiments using cytochalasin D probed microfilament and microtubule roles in A. baumannii invasion. Omp34 prompted antibody production without toxicity in mice. The serum showed bactericidal effects on both strains. Additionally, both A. baumannii strains were found to form biofilms. Omp34 serum was observed to decrease biofilm formation, bacterial adherence, internalization, and proliferation in A549 cells. Furthermore, the use of anti-Omp34 serum enhanced the post-infection survival of the host cell. Pre-exposure of A549 cells to cytochalasin D reduced bacterial internalization, highlighting the role of actin polymerization in the invasion process. Microscopic analysis revealed various interactions, such as adherence, membrane alterations, vacuolization, apoptosis, and cellular damage. Anti-Omp34 serum-exposed A549 cells were protected and showed reduced damage. The findings reveal that A. baumannii can significantly multiply intracellularly within host cells. This suggests the bacterium's ability to establish an environment conducive to its replication by preventing fusion with degradative lysosomes and inhibiting acidification. This finding contributes to the understanding of A. baumannii's intracellular persistence and highlights the role of Omp34 in influencing apoptosis, autophagy, and bacterial adherence, which may impact the development of effective treatments against A. baumannii infections.</p>","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":"699-709"},"PeriodicalIF":2.4,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142557511","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":"Regulation of pyrimidine biosynthesis in the biocontrol bacterium Pseudomonas aureofaciens.","authors":"Lou V Gore, Thomas P West","doi":"10.1007/s12223-025-01259-3","DOIUrl":"10.1007/s12223-025-01259-3","url":null,"abstract":"<p><p>The regulation of the pyrimidine biosynthetic pathway by pyrimidines was investigated in the biological control agent Pseudomonas aureofaciens ATCC 17418. Using succinate as a carbon source, orotic acid or uracil supplementation had a repressive effect in ATCC 17418 cells on dihydroorotate dehydrogenase or orotidine 5'- monophosphate decarboxylase activity but only orotic acid supplementation appeared to repress the level of orotate phosphoribosyltransferase activity. In glucose-grown ATCC 17418 cells, orotic acid supplementation appeared to repress the level of phosphoribosyltransferase or decarboxylase while uracil supplementation depressed the dihydroorotase, dehydrogenase, and decarboxylase activities. The pyrimidine auxotrophic mutant strain GW-2, isolated from ATCC 17418 using chemical mutagenesis and resistance to 5-fluoroorotic acid, was found to be deficient for orotidine 5'-monophosphate decarboxylase activity. Pyrimidine limitation of the succinate-grown mutant strain cells resulted in only a slight derepression of transcarbamoylase activity while pyrimidine limitation of glucose-grown mutant cells caused a derepression of the four active pyrimidine biosynthetic enzyme activities relative to their activities in the mutant cells grown with excess uracil. The control of the known regulatory enzyme aspartate transcarbamoylase was examined in P. aureofaciens ATCC 17418. Transcarbamoylase activity was shown to be inhibited by pyrophosphate, ATP, UTP, and ADP. It was concluded that the pyrimidine biosynthetic pathway in P. aureofaciens ATCC 17418 was subject to regulation at the transcriptional level and at the level of aspartate transcarbamoylase activity, which could be valuable in comprehending its nucleic acid metabolism as well as its taxonomic assignment to the Pseudomonas chlororaphis homology group.</p>","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":"665-672"},"PeriodicalIF":2.4,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143751956","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":"New insights and perspectives on the virulence of hypervirulent Klebsiella pneumoniae.","authors":"Ifeanyi Elibe Mba, Toluwalase Odunayo Mba, Chibuzor Kenneth Uwazie, Fetuata Aminat Aina, Akindele Oluwaseun Kemisola, Ijeoma Josephine Uwazie","doi":"10.1007/s12223-025-01261-9","DOIUrl":"10.1007/s12223-025-01261-9","url":null,"abstract":"<p><p>Klebsiella pneumoniae, a Gram-negative bacterium, comprises strains with diverse virulence potentials, ranging from classical to hypervirulent variants. Understanding the genetic basis underlying the virulence disparities between hypervirulent (hvKp) and classical K. pneumoniae (cKp) strains is crucial. hvKp strains are characterized by hypermucoviscosity, attributed to the presence of specific virulence genes and the production of molecules that aid in their ability to survive, evade host immune defenses, and cause infection. In contrast, classical strains exhibit a broader array of antimicrobial resistance determinants, conferring resistance to multiple antibiotics. Although current definitions of hvKp incorporate clinical features, phenotypes, and genotypes, identifying hvKp strains in clinical settings remains challenging. Genomic studies have been pivotal and have helped to identify distinct genetic profiles in hvKp strains, including unique virulence plasmids and chromosomal variations, underscoring the genetic diversity within K. pneumoniae populations. This review examines the virulence and genetic determinants associated with hvKp. The presence of genes defining hypervirulence, alongside considerations of their utility as biomarkers and targets for therapeutic strategies, is discussed, while also providing insight into biofilm formation by hvKp and key questions that need urgent responses in understanding hvKp.</p>","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":"517-533"},"PeriodicalIF":2.4,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143810890","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":"Prevalence and virulence profiles of ESBL-producing Escherichia coli in urinary and blood infections in South Korea.","authors":"Jong-Hun Ha, Jeong-Ih Shin, Kyu-Min Kim, Jeong-Gyu Choi, Minh Phuong Trinh, Won Jun Anh, Kyung-Min Kang, Hyung-Lyun Kang, Jung-Hyun Byun, Wongwarut Boonyanugomol, Kee Woong Kwon, Myung Hwan Jung, Seung Chul Baik, Woo-Kon Lee, Min-Kyoung Shin","doi":"10.1007/s12223-024-01205-9","DOIUrl":"10.1007/s12223-024-01205-9","url":null,"abstract":"<p><p>Escherichia coli is a significant pathogen in extraintestinal infections, and ESBL-producing E. coli poses a major clinical challenge due to its antibiotic resistance. This study comprehensively analyzed E. coli isolates from urine and blood samples of patients with urinary tract and bloodstream infections at three major tertiary hospitals in South Korea. The goal was to provide insights into the distribution, antibiotic resistance, and virulence factors of these strains. Our analysis identified CTX-M and TEM as the dominant ESBL types, found in 71.7% and 61.7% of isolates, respectively, with 46.7% showing co-occurrence. Multilocus sequence typing (MLST) revealed the predominance of high-risk clones such as ST131, ST69, ST73, and ST95, with rare sequence types like ST410 and ST405 also identified. The high prevalence of virulence factors, including iutA (80.8%) and kpsMII (74.2%), further highlights the complexity of these strains. In addition, 38.3% of clinical isolates contained a combination of siderophore, adhesin, protectin, and toxin-related genes. There was no significant difference between urinary tract and bloodstream infections or regional differentiation in Korea. This study highlights the importance of controlling ESBL-producing E. coli infections, especially given the increasing incidence among patients with underlying medical conditions and older adults who are more susceptible to urinary tract infections. These findings serve as valuable indicators for pathogen analysis, especially those harboring antibiotic resistance and toxin genes. The insights gained are expected to contribute significantly to the development of infectious disease prevention and control strategies.</p>","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":"589-600"},"PeriodicalIF":2.4,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142461620","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":"Thermothelomyces thermophilus cultivated with residues from the fruit pulp industry: enzyme immobilization on ionic supports of a crude cocktail with enhanced production of lichenase.","authors":"Alex Graça Contato, Ana Claudia Vici, Vanessa Elisa Pinheiro, Tássio Brito de Oliveira, Guilherme Guimarães Ortolan, Emanuelle Neiverth de Freitas, Marcos Silveira Buckeridge, Maria de Lourdes Teixeira de Moraes Polizeli","doi":"10.1007/s12223-024-01208-6","DOIUrl":"10.1007/s12223-024-01208-6","url":null,"abstract":"<p><p>β-Glucans comprise a group of β-D-glucose polysaccharides (glucans) that occur naturally in the cell walls of bacteria, fungi, and cereals. Its degradation is catalyzed by β-glucanases, enzymes that catalyze the breakdown of β-glucan into cello-oligosaccharides and glucose. These enzymes are classified as endo-glucanases, exo-glucanases, and glucosidases according to their mechanism of action, being the lichenases (β-1,3;1,4-glucanases, EC 3.2.1.73) one of them. Hence, we aimed to enhance lichenase production by Thermothelomyces thermophilus through the application of response surface methodology, using tamarind (Tamarindus indica) and jatoba (Hymenaea courbaril) seeds as carbon sources. The crude extract was immobilized, with a focus on improving lichenase activity, using various ionic supports, including MANAE (monoamine-N-aminoethyl), DEAE (diethylaminoethyl)-cellulose, CM (carboxymethyl)-cellulose, and PEI (polyethyleneimine)-agarose. Regarding lichenase, the optimal conditions yielding the highest activity were determined as 1.5% tamarind seeds, cultivation at 50 °C under static conditions for 72 h. Moreover, transitioning from Erlenmeyer flasks to a bioreactor proved pivotal, resulting in a 2.21-fold increase in activity. Biochemical characterization revealed an optimum temperature of 50 °C and pH of 6.5. However, sustained stability at varying pH and temperature levels was challenging, underscoring the necessity of immobilizing lichenase on ionic supports. Notably, CM-cellulose emerged as the most effective immobilization medium, exhibiting an activity of 1.01 U/g of the derivative (enzyme plus support), marking a substantial enhancement. This study marks the first lichenase immobilization on these chemical supports in existing literature.</p>","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":"619-629"},"PeriodicalIF":2.4,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142497827","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":"Targeting virulence of resistant Escherichia coli by the FDA-approved drugs sitagliptin and nitazoxanide as an alternative antimicrobial approach.","authors":"Sara M Eltabey, Ali H Ibrahim, Mahmoud M Zaky, Adel Ehab Ibrahim, Yahya Bin Abdullah Alrashdi, Sami El Deeb, Moustafa M Saleh","doi":"10.1007/s12223-024-01215-7","DOIUrl":"10.1007/s12223-024-01215-7","url":null,"abstract":"<p><p>The spread of multidrug-resistant Escherichia coli in healthcare facilities is a global challenge. Hospital-acquired infections produced by Escherichia coli include gastrointestinal, blood-borne, urinary tract, surgical sites, and neonatal infections. Therefore, novel approaches are needed to deal with this pathogen and its rising resistance. The concept of attenuating virulence factors is an alternative strategy that might lead to low levels of resistance and combat this pathogen. A sub-inhibitory concentration (¼ MIC) of sitagliptin and nitazoxanide was used for phenotypic assessments of Escherichia coli virulence factors such as biofilm production, swimming motility, serum resistance, and protease production. Moreover, qRT-PCR was used to determine the impact of sub-MIC of the tested drugs on the relative expression levels of papC, fimH, fliC, kpsMTII, ompT_m, and stcE genes encoding virulence factors in Escherichia coli. Also, an in vivo model was conducted as a confirmatory test. Phenotypically, our findings demonstrated that the tested strains showed a significant decrease in all the tested virulence factors. Moreover, the genotypic results showed a significant downregulation in the relative expression levels of all the tested genes. Besides, the examined drugs were found to be effective in protecting mice against Escherichia coli pathogenesis. Sitagliptin and nitazoxanide exhibited strong anti-virulence activities against Escherichia coli. In addition, it is recommended that they might function as adjuvant in the management of Escherichia coli infections with either conventional antimicrobial agents or alone as alternative treatment measures.</p>","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":"645-656"},"PeriodicalIF":2.4,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142544665","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}