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Microbiol. Res., Volume 17, Issue 5 (May 2026) – 16 articles

Cover Story (view full-size image): In this review, we examine how Escherichia coli, one of the most versatile microbial platforms in biotechnology, can be systematically engineered to overproduce these compounds through the shikimate pathway, a metabolic route absent in mammals but conserved across bacteria, fungi, and plants. We discuss strategies organized around the key metabolic nodes chorismate, L-Tyrosine, L-Phenylalanine, and L-Tryptophan, covering classical metabolic engineering approaches and emerging synthetic biology tools, including CRISPR-based regulation, biosensor-driven dynamic control, membrane engineering, and synthetic microbial consortia. This integrated perspective highlights both the remarkable progress achieved and the critical challenges that remain, offering a roadmap for developing efficient, scalable microbial cell factories for aromatic-compound bioproduction. View this paper
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13 pages, 261 KB  
Article
Prevalence and Genotyping of Human Papillomavirus in Oral Squamous Cell Carcinoma, Oral Potentially Malignant Disorders, and Healthy Oral Mucosa: A Cross-Sectional Study
by Teodora Bolyarova, Pavel Stanimirov, Ivo Sirakov, Emilia Naseva, Bilyana Sirakova, Konstantin Stamatov and Samuil Dzhenkov
Microbiol. Res. 2026, 17(5), 99; https://doi.org/10.3390/microbiolres17050099 - 21 May 2026
Cited by 1 | Viewed by 196
Abstract
Background and Objectives: This study aimed to detect and genotype human papillomavirus (HPV) in tissues from oral squamous cell carcinoma (OSCC), oral potentially malignant disorders (OPMD), and healthy individuals. Materials and Methods: The study included 60 patients (31 men and 29 women; median [...] Read more.
Background and Objectives: This study aimed to detect and genotype human papillomavirus (HPV) in tissues from oral squamous cell carcinoma (OSCC), oral potentially malignant disorders (OPMD), and healthy individuals. Materials and Methods: The study included 60 patients (31 men and 29 women; median age 60 years, IQR 41.5–69.8) admitted to the Department of Dental, Oral and Maxillofacial Surgery, Medical University of Sofia. Patients were divided into three groups: healthy oral mucosa (n = 20), OPMD (n = 20), and OSCC (n = 20). HPV was tested using punch biopsies with nested PCR and chip technology. Results: Low-risk HPV was found in four (20%) healthy individuals (types 6/11, 43), seven (35%) OPMD patients (types 6/11, 42, 43), and eleven (55%) OSCC patients (types 6/11, 42, 43). Pairwise comparison showed a significant difference in HPV positivity between healthy individuals and OSCC patients (p = 0.022). Among all HPV-positive OPMDs, the virus was detected in two leukoplakia cases (28.6%), three lichen planus cases (42.9%), one lichenoid lesion case (14.3%), and one proliferative verrucous leukoplakia case (14.3%). According to binary logistic regression, OSCC patients were 4.9 times more likely to be HPV-positive compared to healthy individuals (p = 0.027). Conclusions: HPV infection may play a potential role in the pathogenesis of OPMD and OSCC. Full article
(This article belongs to the Section Medical and Veterinary Microbiology)
11 pages, 427 KB  
Article
Multidrug-Resistant Bacterial Strains in Northern Mexico: Clinical Impact and Vitek 2-Based Characterization
by Rafael Martínez-Miranda, Fernando A. Solis-Dominguez, Aseneth Herrera-Martínez, Conrado Garcia-Gonzalez, Jonathan Isaac Arauz Cabrera, Rafael Iván Ayala Figueroa and Carlos Vidal Montiel Castañeda
Microbiol. Res. 2026, 17(5), 100; https://doi.org/10.3390/microbiolres17050100 - 21 May 2026
Viewed by 583
Abstract
Antibiotic resistance remains a major public health concern, particularly in regions with high rates of hospital- and community-acquired infections. This study aimed to quantify multidrug-resistant (MDR) bacterial strains in northern Mexico and to identify the most prevalent resistance phenotypes, the antibiotic classes with [...] Read more.
Antibiotic resistance remains a major public health concern, particularly in regions with high rates of hospital- and community-acquired infections. This study aimed to quantify multidrug-resistant (MDR) bacterial strains in northern Mexico and to identify the most prevalent resistance phenotypes, the antibiotic classes with the highest resistance and susceptibility rates, the predominant MDR species, and the specimen types yielding the greatest number of isolates. Clinically relevant strains were collected from patients with confirmed infections. Microorganism identification and antimicrobial susceptibility test-ing were performed using the Vitek 2 Compact system (bioMérieux), and the results were analyzed descriptively. Of the 1544 strains analyzed, 761 (49.29%) exhibited multidrug resistance. Escherichia coli was the most frequently isolated MDR species, followed by Pseudomonas aeruginosa. Acinetobacter baumannii showed the highest resistance rate, with 95.55% of its strains classified as MDR, whereas P. aeruginosa had the lowest MDR proportion at 30.73%. These findings underscore the urgent need for rational antibiotic use and the development of new therapeutic agents, particularly those targeting Gram-negative bacilli, to mitigate the growing threat of antimicrobial resistance in this region. Full article
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15 pages, 1051 KB  
Article
Association of HHV-6 Reactivation with NLRP3 Inflammasome Activation in Chemotherapy-Treated Iraqi Cancer Patients: A Cross-Sectional Study
by Nadia Habeeb Sarhan, Maroua Gdoura-Ben Amor, Saif Jabbar Yasir and Radhouane Gdoura
Microbiol. Res. 2026, 17(5), 98; https://doi.org/10.3390/microbiolres17050098 - 19 May 2026
Viewed by 212
Abstract
Human herpesvirus 6 (HHV-6) typically remains latent but can reactivate during immunosuppression caused by chemotherapy, potentially driving immune dysregulation. The NLRP3 inflammasome is a critical innate immune complex mediating pro-inflammatory signaling implicated in tumor progression and treatment toxicity. This study investigated the association [...] Read more.
Human herpesvirus 6 (HHV-6) typically remains latent but can reactivate during immunosuppression caused by chemotherapy, potentially driving immune dysregulation. The NLRP3 inflammasome is a critical innate immune complex mediating pro-inflammatory signaling implicated in tumor progression and treatment toxicity. This study investigated the association between HHV-6 antigenemia and NLRP3 inflammasome activation in 193 chemotherapy-treated cancer patients at the Oncology Hospital in Al-Najaf, Iraq. Serological markers for HHV-6 IgG, IgM, and circulating viral antigen, along with serum NLRP3 levels, were quantified using ELISA. Active HHV-6 antigenemia was observed in over half the cohort, with 56.5% positive for IgM and 42.5% exhibiting antigenemia. Elevated serum NLRP3 levels were detected in 65.8% of patients and correlated significantly with HHV-6 antigen presence, particularly in hematological and genitourinary cancers. Viral antigenemia and inflammasome activity were more prominent in females and older patients. Host gene analysis revealed Hepcidin (HAMP) polymorphisms and altered expression compared to healthy controls, suggesting links between iron metabolism, viral antigenemia, and inflammasome activity. These findings highlight a potential mechanistic connection between HHV-6 antigenemia and inflammasome-driven inflammation, which may contribute to chemotherapy-associated immune dysregulation. Monitoring HHV-6 antigenemia and NLRP3 activation may offer valuable insight into the inflammatory status of cancer patients undergoing chemotherapy. Full article
(This article belongs to the Special Issue Host–Microbe Interactions in Health and Disease)
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17 pages, 842 KB  
Article
Bioactivity of Pod and Seed Extracts from Leucaena leucocephala, Prosopis laevigata, and Pithecellobium dulce Collected in Oaxaca, Mexico
by Jesús Andres Morales-López, Teodulfo Aquino-Bolaños, Angélica Bautista-Cruz, Tamara Aquino-Aguilar, Edgar García-Sánchez, Tlacaelel Aquino-López and Keyla Cruz-García
Microbiol. Res. 2026, 17(5), 97; https://doi.org/10.3390/microbiolres17050097 - 19 May 2026
Viewed by 175
Abstract
Guaje (Leucaena leucocephala), mezquite (Prosopis laevigata), and guamuchil (Pithecellobium dulce) are leguminous trees distributed throughout southeastern Mexico. Their pods and seeds constitute the main agroecological residues and represent a natural source of secondary metabolites with high biotechnological [...] Read more.
Guaje (Leucaena leucocephala), mezquite (Prosopis laevigata), and guamuchil (Pithecellobium dulce) are leguminous trees distributed throughout southeastern Mexico. Their pods and seeds constitute the main agroecological residues and represent a natural source of secondary metabolites with high biotechnological potential. The aim of this study was to determine the chemical composition, antimicrobial and antioxidant activities, and toxicity of the pods and seeds of L. leucocephala, P. laevigata, and P. dulce. It was found that pod extracts contained higher concentrations of phenolic compounds, flavonoids, and terpenes than seed extracts. Antimicrobial assays showed inhibition zones ranging from 8.1–14.7 mm (E. coli), 8.8–15.1 mm (S. aureus), 11.3–15.4 mm (E. faecalis), 8.9–24.1 mm (C. albicans), and 8.5–22.6 mm (C. krusei). The ethyl acetate (AVPD) and ethanolic (EVPD) extracts from P. dulce pods showed the highest antimicrobial activity, with MIC values ranging from 0.03 to 0.15 mg/mL, MBC values of 0.07 mg/mL (S. aureus and E. faecalis), and MFC values of 1.25 mg/mL (C. albicans) and 0.62 mg/mL (C. krusei). Antioxidant activity was higher in pod extracts, with AVPD and EVPD showing IC50 values of 0.257 and 0.320 mg/mL, respectively. Consistently, EVPD exhibited the highest phenolic content (133.24 mg GAE/g) and flavonoid content (50.90 mg QE/g), followed by AVPD (87.29 mg GAE/g and 42.40 mg QE/g, respectively). The results indicate that pod extracts of L. leucocephala and P. dulce contain secondary metabolites with broad antimicrobial and antioxidant potential and low toxicity. Full article
(This article belongs to the Special Issue Advances in Plant–Pathogen Interactions)
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13 pages, 6093 KB  
Article
Real-Time Fluorescence Imaging Platform for Screening Arbuscular Mycorrhizal Fungi by Hyphal Transport Kinetics
by Guangle Zhang, Lixue Yuan, Yongxin Zhang, Xiaohang Wang, Li Zhang, Xinyuan Zhang, Ruxue Chen, Zhuangzhuang Wang, Bo Yu and Yonghua Wang
Microbiol. Res. 2026, 17(5), 96; https://doi.org/10.3390/microbiolres17050096 - 19 May 2026
Viewed by 200
Abstract
Arbuscular mycorrhizal (AM) fungi form mutualistic symbioses with about 80% of land plants and play a key role in improving host inorganic phosphate (Pi), nitrogen, and water acquisition. Traditional AM fungi research relies on field trials, compartmented cultivation, and pot cultures—methods that are [...] Read more.
Arbuscular mycorrhizal (AM) fungi form mutualistic symbioses with about 80% of land plants and play a key role in improving host inorganic phosphate (Pi), nitrogen, and water acquisition. Traditional AM fungi research relies on field trials, compartmented cultivation, and pot cultures—methods that are time-consuming (taking months to years) and unable to monitor dynamic transport, thus limiting efficient strain screening. We developed a real-time fluorescence imaging platform integrating sterile symbiotic microchambers with photodiode array detection. This system enables the non-invasive, quantitative tracking of hyphal cytoplasmic streaming and transport kinetics at the plant–fungal interface. Distinct AM fungi strains exhibit significant differences in fluorescence kinetics—such as accumulation rate and peak intensity—providing measurable indicators of transport efficiency. Our method overcomes the temporal and technical limitations of conventional AM fungi screening approaches. By enabling simultaneous real-time monitoring, it shortens screening cycles and provides new insights for the (1) precise screening of AM fungi strains for efficient nutrient transport; (2) investigation of nutrient exchange mechanisms; (3) development of sustainable microbial inoculants. Full article
(This article belongs to the Topic New Challenges on Plant–Microbe Interactions)
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19 pages, 1244 KB  
Article
Optimization of IAA Production by Halotolerant Vreelandella titanicae J113 Through Fermentation Process Engineering with Response Surface Methodology
by Dilbar Tursun, Zulhumar Yakup, Huifang Bao, Faqiang Zhan, Yingwu Shi, Hongmei Yang, Jiusheng Sun, Shijie Fang and Ning Wang
Microbiol. Res. 2026, 17(5), 95; https://doi.org/10.3390/microbiolres17050095 - 12 May 2026
Viewed by 244
Abstract
Soil salinization is a significant environmental factor limiting agricultural production. Developing salt–alkali-tolerant microbial resources is important for the improvement of saline–alkali land. Plant growth-promoting rhizobacteria stimulate crop growth by producing the plant growth hormone indole-3-acetic acid (IAA), but their fermentation process under salt [...] Read more.
Soil salinization is a significant environmental factor limiting agricultural production. Developing salt–alkali-tolerant microbial resources is important for the improvement of saline–alkali land. Plant growth-promoting rhizobacteria stimulate crop growth by producing the plant growth hormone indole-3-acetic acid (IAA), but their fermentation process under salt stress still needs optimization. Single-factor experiments and response surface methodology (RSM) were used to systematically optimize the fermentation conditions of the salt–alkali-tolerant Vreelandella titanicae J113. Key influencing factors were screened using the single-factor experiment design, and optimal process parameters were determined using the Box–Behnken design. IAA production and cell biomass were used as evaluation indicators to study the interactions of carbon sources, nitrogen sources, inorganic salts, temperature, cultivation time, and inoculum size. The optimal fermentation process was obtained: starch concentration 17.5 g/L, NaCl concentration 32.5 g/L, yeast extract 5 g/L, cultivation temperature 30 °C, inoculum size 3%, and cultivation time 144 h. After optimization, IAA production reached 23.02 μg/mL, an increase of 115% compared with before optimization. Salt stress experiments showed that the strain could still maintain high IAA production under 3% NaCl, demonstrating good salt tolerance. Maize seed germination experiments demonstrated that the optimized fermentation broth significantly promoted seed germination and seedling growth under salt stress conditions, with root length, fibrous root number, and fresh weight increasing by 61–86%, 137–200%, and 25–57%, respectively, compared to the control group. This study established an efficient IAA fermentation process for the salt–alkali-tolerant Vreelandella titanicae J113, providing technical support for developing microbial plant growth regulators suitable for saline–alkali land. The optimized strain exhibits excellent growth-promoting potential under salt stress conditions, offering favorable application prospects. Full article
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18 pages, 6291 KB  
Review
Engineering Escherichia coli for Aromatic Compound Biosynthesis: Integrating Metabolic Engineering and Synthetic Biology
by Silvana M. Tapia-Cabrera, Adelfo Escalante and Francisco Bolívar
Microbiol. Res. 2026, 17(5), 94; https://doi.org/10.3390/microbiolres17050094 - 9 May 2026
Viewed by 470
Abstract
Aromatic compounds derived from the shikimate (SHK) pathway constitute a diverse class of high-value molecules with applications in the pharmaceutical, food, cosmetic, and chemical industries. In microbial systems, particularly Escherichia coli, this pathway links central carbon metabolism (CCM) to the biosynthesis of [...] Read more.
Aromatic compounds derived from the shikimate (SHK) pathway constitute a diverse class of high-value molecules with applications in the pharmaceutical, food, cosmetic, and chemical industries. In microbial systems, particularly Escherichia coli, this pathway links central carbon metabolism (CCM) to the biosynthesis of L-tyrosine (L-Tyr), L-phenylalanine (L-Phe), and L-tryptophan (L-Trp), which serve as key precursors for structurally diverse metabolites. Over the past decades, metabolic engineering strategies have focused on increasing precursor availability, relieving feedback inhibition, and eliminating competing pathways. More recently, advances in synthetic biology have enabled dynamic control of metabolic flux through pathway modularization, genome-scale interventions, and regulatory circuit design. In this review, we provide a comprehensive overview of the engineering of E. coli for aromatic compound biosynthesis, highlighting key developments in the optimization of the SHK pathway and its major metabolic nodes chorismate, L-Tyr, L-Phe, and L-Trp. We examine emerging approaches, including CRISPR-based regulation, biosensor-driven dynamic control, membrane engineering, and synthetic microbial consortia. Despite significant progress, challenges related to pathway regulation, cofactor balance, metabolic burden, and product toxicity remain critical bottlenecks. Integrating metabolic engineering with synthetic biology is driving the development of programmable, scalable microbial platforms for the efficient bioproduction of aromatic compounds. Full article
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13 pages, 518 KB  
Article
Molecular Epidemiology of Drug-Resistant Mycobacterium tuberculosis: Mutation Profiles and Resistance Associations
by Mandlenkosi Manika, Lindiwe Modest Faye, Ntandazo Dlatu and Mojisola Clara Hosu
Microbiol. Res. 2026, 17(5), 93; https://doi.org/10.3390/microbiolres17050093 - 8 May 2026
Viewed by 332
Abstract
Background: The global burden of drug-resistant Mycobacterium tuberculosis continues to threaten tuberculosis control efforts, largely due to the emergence and transmission of resistance-associated genetic mutations. Molecular epidemiology provides critical insights into mutation profiles and resistance associations, yet the interplay among key mutations and [...] Read more.
Background: The global burden of drug-resistant Mycobacterium tuberculosis continues to threaten tuberculosis control efforts, largely due to the emergence and transmission of resistance-associated genetic mutations. Molecular epidemiology provides critical insights into mutation profiles and resistance associations, yet the interplay among key mutations and their contributions to complex resistance patterns remains poorly understood, particularly in high-burden settings. Methods: A retrospective, cross-sectional, laboratory-based design was used to analyze 111 phenotypically confirmed drug-resistant isolates. Molecular drug susceptibility testing (DST) for first- and second-line anti-tuberculosis drugs was performed at the National Health Laboratory Service (NHLS) TB reference laboratory. Drug-resistance profiles were classified according to World Health Organization (WHO) definitions. Descriptive and inferential statistical analyses were conducted to determine mutation frequencies, co-occurrence patterns, and associations with resistance profiles. Results: rpoB (D435V 38.7%; S450L 36.0%) and katG (S315T 80.2%) mutations predominated, forming the core molecular basis of MDR-TB, while 15% harbored inhA promoter mutations associated with low-level isoniazid resistance. The most frequent combinations included rpoB S450L with katG S315T and rpoB D435V with katG S315T, consistent with multidrug-resistant tuberculosis (MDR-TB) profiles. Nearly 48% showed dual resistance to fluoroquinolones and second-line injectables. Conclusion: This study highlights the predominance of resistance-associated mutations and their co-occurrence patterns in shaping MDR-TB profiles in the study setting. The observed burden of second-line drug resistance underscores the importance of comprehensive resistance testing. These findings support the use of mutation profiling for rapid diagnosis and informed treatment decisions, while emphasizing the need for ongoing local surveillance to guide TB control efforts. Full article
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22 pages, 1290 KB  
Systematic Review
Molecular and Proteomic Determinants of Trypanosoma cruzi Adaptation Within Triatomine Vectors: Insights from Current Experimental Models
by Jessy T. Santana, Berenice González-Rete, Elia Torres-Gutiérrez, Juliana Cordeiro Cardoso, Cláudia Moura Melo and Paz M. S. Salazar-Schettino
Microbiol. Res. 2026, 17(5), 92; https://doi.org/10.3390/microbiolres17050092 - 8 May 2026
Viewed by 359
Abstract
Trypanosoma cruzi exhibits complex genetic diversity, organized into seven distinct typing units. To complete its life cycle, the parasite must adapt to the digestive tract of various species of triatomine bugs. This systematic review aimed to understand the molecular adaptation mechanisms of T. [...] Read more.
Trypanosoma cruzi exhibits complex genetic diversity, organized into seven distinct typing units. To complete its life cycle, the parasite must adapt to the digestive tract of various species of triatomine bugs. This systematic review aimed to understand the molecular adaptation mechanisms of T. cruzi in relation to different vector species, systematizing knowledge on vector competence. Following PRISMA guidelines, 18 experimental studies (published between 1995 and 2025) were selected from the ScienceDirect, PubMed, Scopus, and Web of Science databases, focusing on the parasite–vector interface and proteomic analyses. There was a predominance of studies conducted in Brazil (66.67%), using the Rhodnius prolixus model (72.22%) and the TcI strain (clone Dm28c). The evolution of methodological approaches reflects a transition from classical techniques, such as SDS-PAGE, to high-throughput omics strategies, including LC-MS/MS and gene editing tools such as CRISPR. The findings were organized into key biological processes, including parasite adhesion mediated by perimicrovillar membrane components, glycoinositolphospholipids (GIPLs), and mucins; the influence of the metabolic and nutritional microenvironment, particularly hemoglobin-derived peptides and glucose availability; and the role of intestinal redox conditions in triggering metacyclogenesis. Overall, the available evidence suggests that T. cruzi adaptation within triatomine vectors is a multifactorial process driven by proteomic reprogramming and post-transcriptional regulation in response to environmental signals within the vector gut. However, this understanding is largely derived from studies based on Rhodnius prolixus and TcI strains, which limits the generalization of these mechanisms across other triatomine species and parasite lineages. Full article
(This article belongs to the Special Issue Host–Microbe Interactions in Health and Disease)
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17 pages, 1612 KB  
Article
Impact of Pre-Existing Uterine Microbiome on Pregnancy Success After Embryo Transfer in Cattle
by Nilton Luis Murga Valderrama, Gleni T. Segura, Jakson Ch Del Solar, Hugo Frias, Ana C. Romani, Deiner J. Gongora-Bardales, Ulises S. Quispe-Gutierrez, Carla Maria Ordinola-Ramirez, Richard C. Polveiro, Dielson da S. Vieira, Jorge Luis Maicelo Quintana and Rainer M. Lopez Lapa
Microbiol. Res. 2026, 17(5), 91; https://doi.org/10.3390/microbiolres17050091 - 8 May 2026
Viewed by 312
Abstract
The uterine microbiome plays a critical role in maintaining pH balance, modulating the immune system, and influencing fertility, especially in artificial breeding contexts. This study examined the impact of uterine microbiota on pregnancy success in cows following embryo transfer (ET), using Illumina 16S [...] Read more.
The uterine microbiome plays a critical role in maintaining pH balance, modulating the immune system, and influencing fertility, especially in artificial breeding contexts. This study examined the impact of uterine microbiota on pregnancy success in cows following embryo transfer (ET), using Illumina 16S rRNA gene sequencing of the V4 hypervariable region of samples collected from the uterine horn (UH) and the uterine body (UB) of cows during the estrous cycle preceding synchronization for ET in the Amazon region. Microbiomes from the uterine horn (UH) and the uterine body (UB) were analyzed before embryo transfer. Cows that became pregnant (UH-P and UB-P) and those that did not (UH-NP and UB-NP) were compared. Fifteen cows were grouped as follows: UB-P (three), UB-NP (five), UH-P (three), and UH-NP (four). Linear discriminant analysis effect size and heat tree analyses identified Sphingobacterium and Stenotrophomonas spp. as significantly enriched in the UB-P and UH-NP groups, respectively. Additionally, non-pregnant cows exhibited more distinctive genera than pregnant ones. These findings suggest that cows achieving pregnancy have lower microbial diversity and fewer potentially pathogenic genera. This study contributes to the emerging field of pre-pregnancy uterine microbiome research in cattle, offering evidence that microbial composition may influence reproductive success, and highlights specific taxa as potential biomarkers for pregnancy outcomes following embryo transfer. Full article
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13 pages, 5857 KB  
Article
Detection and Host Range Investigation of Phytopythium helicoides and Phytopythium palingenes
by Petya Koeva Christova
Microbiol. Res. 2026, 17(5), 90; https://doi.org/10.3390/microbiolres17050090 - 30 Apr 2026
Viewed by 278
Abstract
Phytopythium species are water molds that have been divided as a separate group of oomycetes about 10 years ago. They are associated with diverse environments worldwide, but the ecological function of most of the species is still under investigation. In the present study, [...] Read more.
Phytopythium species are water molds that have been divided as a separate group of oomycetes about 10 years ago. They are associated with diverse environments worldwide, but the ecological function of most of the species is still under investigation. In the present study, isolation and characterization of Pp. helicoides and Pp. palingenes are described. Both Phytopythium isolates originate from an aquatic environment and were derived from infected leaves. A host range of Pp. helicoides and Pp. palingenes using pathogenicity tests with leaves and cuttings from trees, bushes, perennial and herbaceous plants that belong to 15 different families was studied. Out of 21 tested plants, 18 were susceptible to infection with Pp. helicoides and nine were negatively affected by Pp. palingenes. Pp. helicoides is distinguished by higher aggressiveness and a wider range of potential host species. These results indicate that the impact of pathogenic species from the genus Phytopythium on forests and other natural ecosystems could be much more significant than is currently known. Full article
(This article belongs to the Special Issue Advances in Plant–Pathogen Interactions)
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12 pages, 732 KB  
Article
Enterococcus durans Secretome Modulates Interleukins Gene Expressions in Intestinal Epithelial Cells Challenged by Staphylococcus aureus Secretome: In Vitro Study on the HT-29 Cell Line
by Egidia Costanzi, Giovanna Traina, Marco Misuraca, Donia Msakni, Giada Sgaravizzi, Musafiri Karama, Ebtesam Al-Olayan, Saeed El-Ashram, Marcelo Martinez-Barbitta, Massimo Zerani and Beniamino T. Cenci-Goga
Microbiol. Res. 2026, 17(5), 89; https://doi.org/10.3390/microbiolres17050089 - 30 Apr 2026
Viewed by 376
Abstract
The present study examined the effect of Enterococcus durans cell-free supernatant (CFS) on interleukin (IL)-8, -10 and -1β gene expressions in the intestinal cell line HT-29 treated with Staphylococcus aureus CFS. HT-29 cells were incubated with E. durans CFS or S. aureus [...] Read more.
The present study examined the effect of Enterococcus durans cell-free supernatant (CFS) on interleukin (IL)-8, -10 and -1β gene expressions in the intestinal cell line HT-29 treated with Staphylococcus aureus CFS. HT-29 cells were incubated with E. durans CFS or S. aureus CFS, or S. aureus CFS plus E. durans CFS. All concentrations of E. durans CFS did not show cytotoxicity, while the highest treatment (44.9 μg/mL) with S. aureus CFS induced significant cell death. S. aureus CFS did not modify IL-1β gene expression, while E. durans CFS alone or in combination with S. aureus CFS reduced it. Treatment with S. aureus CFS induced greater expression of the IL-8 gene compared to S. aureus CFS plus E. durans CFS. S. aureus CFS alone or in combination with E. durans CFS increased the expression of the IL-10 gene, while E. durans CFS alone did not modify it. These results suggest a potential protective role of the E. durans secretome in mitigating the inflammatory environment in intestinal cells. This treatment could be useful to protect against possible contact with dangerous soluble microbial products present in food. Full article
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8 pages, 199 KB  
Communication
Serological Investigation of Infectious Bovine Rhinotracheitis in Dromedary Camels and Dairy Herds in Tunisia: Preliminary Results
by Stefano Petrini, Mohamed Methnani, Cecilia Righi, Khaled El Hicheri, Cristina Casciari, Aida Tatli, Ben Smida Boubaker, Elena Tinelli, Sana Kacem, Claudia Pellegrini, Roberto Sabato, Francesco Feliziani and Giovanni Pezzotti
Microbiol. Res. 2026, 17(5), 88; https://doi.org/10.3390/microbiolres17050088 - 29 Apr 2026
Viewed by 378
Abstract
Livestock farming represents a key economic activity in the Tataouine Governorate of southern Tunisia, where cattle and dromedary camels coexist. Varicellovirus bovinealpha1 (BoAHV-1), the etiological agent of infectious bovine rhinotracheitis (IBR), primarily affects cattle, while its circulation in camelids remains poorly understood. Following [...] Read more.
Livestock farming represents a key economic activity in the Tataouine Governorate of southern Tunisia, where cattle and dromedary camels coexist. Varicellovirus bovinealpha1 (BoAHV-1), the etiological agent of infectious bovine rhinotracheitis (IBR), primarily affects cattle, while its circulation in camelids remains poorly understood. Following recent European Union regulations requiring BoAHV-1 surveillance in multiple animal species, this short communication reports serological findings from dairy cattle and dromedary herds in southern Tunisia. In March 2024, serum samples were collected from four non-vaccinated farms, including two intensive Friesian dairy cattle herds and two extensive dromedary herds (50 animals each). Serum samples from all animals were tested for BoAHV-1 antibodies using competitive commercial gB- and gE-based enzyme-linked immunosorbent assays (c-ELISA) and confirmed by virus neutralization test (VNT). Antibodies against BoAHV-1 were detected in cattle from both dairy farms, with low seroprevalence and neutralizing antibody titers, indicating past or ongoing exposure. In contrast, all dromedary samples tested seronegative by both c-ELISA and VNT. These findings confirm BoAHV-1 circulation in cattle in the Tataouine region and its absence in dromedaries at sampling. Further studies involving larger sample sizes and molecular investigations are required to clarify the potential role of camelids in BoAHV-1 epidemiology in southern Tunisia. Full article
28 pages, 510 KB  
Review
Rapid Antimicrobial Susceptibility Testing (AST): Overview of New Commercially Available Automated Phenotypic Tools for Minimum Inhibitory Concentration (MIC) Determination
by Giorgia Piccinini, Antonio Curtoni, Alessandro Bondi, Mattia Genco, Fabio Longo, Carlotta Polizzi, Paolo Valesella, Silvia Corcione, Francesco Giuseppe De Rosa and Cristina Costa
Microbiol. Res. 2026, 17(5), 87; https://doi.org/10.3390/microbiolres17050087 - 29 Apr 2026
Viewed by 1112
Abstract
Antimicrobial resistance (AMR) represents one of the most urgent global health threats, significantly impacting patient outcomes, healthcare systems, and economic sustainability. Rapid and accurate antimicrobial susceptibility testing (AST) are essential to guide targeted therapy, reduce inappropriate antimicrobial use, and support antimicrobial stewardship programs. [...] Read more.
Antimicrobial resistance (AMR) represents one of the most urgent global health threats, significantly impacting patient outcomes, healthcare systems, and economic sustainability. Rapid and accurate antimicrobial susceptibility testing (AST) are essential to guide targeted therapy, reduce inappropriate antimicrobial use, and support antimicrobial stewardship programs. However, conventional phenotypic AST methods, including broth microdilution, disk diffusion, agar dilution, and gradient strip tests, remain labor-intensive and require prolonged turnaround times, often delaying optimal therapeutic decisions. Although automated commercial platforms such as VITEK 2, BD Phoenix, MicroScan WalkAway, and Sensititre ARIS have improved laboratory workflow and standardization, they still rely on culture-based approaches and typically require 16–36 h to generate minimum inhibitory concentration (MIC) results. In recent years, several innovative rapid phenotypic AST technologies have emerged, aiming to significantly shorten the time to susceptibility results while maintaining high accuracy. This review provides an overview of currently available rapid automated phenotypic platforms for MIC determination, including VITEK® Reveal™, ASTar, FASTinov®AST, QuickMIC®, and the Accelerate Pheno® system. These systems employ advanced technologies such as volatile organic compound detection, flow cytometry, microfluidics, real-time imaging, and morphokinetic cellular analysis to deliver susceptibility results within a few hours directly from positive blood cultures. We summarize their technical principles, antibiotics and pathogens included, performances, and current limitations. Overall, the implementation of rapid phenotypic AST tools has the potential to substantially improve clinical decisions, optimize antimicrobial therapy, and contribute to fight AMR. Full article
(This article belongs to the Special Issue Antimicrobial Resistance: New Diagnostic Strategies)
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16 pages, 2555 KB  
Article
Molecular Epidemiology, Hematobiochemical Alterations, and Oxidative Stress-Induced Genotoxicity of Equine Trypanosomiasis in Pakistan
by Waqas Ahmad, Naeem Rasool, Qurat ul Ain, Usama Bin Naeem, Muhammad Azeem, Umbreen Anwar, Tehreem Fayyaz, Zeba Amjad, Muhammad Yasin Tipu and Mehmood Ahmad
Microbiol. Res. 2026, 17(5), 86; https://doi.org/10.3390/microbiolres17050086 - 27 Apr 2026
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Abstract
Trypanosoma evansi (T. evansi) infection poses a significant health threat to equines. This study was aimed to assess the prevalence, risk factors, hematobiochemical alterations, and oxidative stress-mediated genotoxicity associated with equine trypanosomiasis in the Rahim Yar Khan District. This cross-sectional study [...] Read more.
Trypanosoma evansi (T. evansi) infection poses a significant health threat to equines. This study was aimed to assess the prevalence, risk factors, hematobiochemical alterations, and oxidative stress-mediated genotoxicity associated with equine trypanosomiasis in the Rahim Yar Khan District. This cross-sectional study was conducted on 384 equines from October 2024 to September 2025. Blood samples were collected for thin blood film microscopy and PCR assay using RoTat 1.2 primers. Hematological indices were analyzed with an automated hematology analyzer; serum biochemical parameters were quantified via standard assays. Oxidative stress markers, including malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD), and reduced glutathione (GSH), were also measured. Genotoxicity was evaluated using the alkaline comet assay. Statistical analyses included the chi-square test, logistic regression, and independent t-tests. T. evansi was detected in 5.99% of samples by microscopy and 10.16% by PCR, with no significant association with species, age, or sex. Infected equines exhibited significant reductions in hemoglobin (5.4 ± 0.6 vs. 10.8 ± 0.5 g/dL; p < 0.0001), total serum protein (2.1 ± 0.3 vs. 5.8 ± 0.2 g/dL; p < 0.0001), albumin, and globulin, alongside elevated hepatic enzymes, blood urea nitrogen, and creatinine (all p < 0.01). Oxidative stress was confirmed by increased MDA (p < 0.0001) and decreased CAT activity (p < 0.001). Genotoxicity was significantly higher in infected animals (genetic damage index; 1.12 ± 0.08 vs. 0.40 ± 0.01; p < 0.01). This study provides the first integrated assessment of molecular epidemiology and oxidative stress-mediated genotoxicity in equines in this region, suggesting the pathogenic impact of the infection and targeted diagnostics for disease management strategies. Full article
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Article
Antimicrobial Effect of Slightly Acidic Hypochlorous Acid Water Against Biofilm Formed by Candida parapsilosis
by Jun Iwahashi, Akiko Shimizu, Akinobu Togo, Hiroshi Fuketa, Kenji Gotoh, Keisuke Ohta, Norihiro Shinkai, Naohisa Kawamura and Hiroshi Watanabe
Microbiol. Res. 2026, 17(5), 85; https://doi.org/10.3390/microbiolres17050085 - 24 Apr 2026
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Abstract
Background: Many of the pathogenic bacteria and fungi found in hospital environments form biofilms, which allow them to persist in the environment for long periods, posing a risk of hospital-acquired infections. Although the pathogens within biofilms often have reduced levels of drug susceptibility, [...] Read more.
Background: Many of the pathogenic bacteria and fungi found in hospital environments form biofilms, which allow them to persist in the environment for long periods, posing a risk of hospital-acquired infections. Although the pathogens within biofilms often have reduced levels of drug susceptibility, the efficacy of disinfectants routinely applied against planktonic pathogens must be evaluated against biofilms as well. Our objective in this study was to determine the efficacy of treatment using slightly acidic hypochlorous acid water and to compare the results with sodium hypochlorite when both were used to disinfect Candida parapsilosis biofilms. Methods: C. parapsilosis in the planktonic or biofilm state was treated with each disinfectant. The number of viable cells that remained was determined, and scanning electron microscopy (SEM) of the disinfectant-treated biofilms was performed. Results: Compared with sodium hypochlorite, in a shorter period of time, hypochlorous acid water completely killed not only planktonic C. parapsilosis but also C. parapsilosis in a biofilm that had been formed for 72 h. SEM showed that both disinfectants were effective in removing the C. parapsilosis biofilm to some extent. Conclusions: Slightly acidic hypochlorous acid water appears to be an effective disinfectant against C. parapsilosis both in suspension and in biofilms. Full article
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