Folia microbiologica最新文献

{"title":"Biofilm formation efficiency by Candida species isolated from gastric mucosa of intragastric balloon patient under extremely low pH.","authors":"Andressa Prado, Flávia Franco Veiga, Rubens de Oliveira Brito, Elton da Cruz Alves Pereira, Melyssa Negri, Terezinha Inez Estivalet Svidzinski","doi":"10.1007/s12223-025-01286-0","DOIUrl":"https://doi.org/10.1007/s12223-025-01286-0","url":null,"abstract":"<p><p>This study characterized biofilms formed by Candida albicans and C. tropicalis isolated from the gastric mucosa biopsies of an intragastric balloon (IGB) patient user. Both were cultivated to form single and mixed artificial biofilms at pH 2.5 and 5.5 for 24 and 48 h. The biofilms were assessed for biochemical, metabolic, and ultrastructural properties. Yeast counts in monospecies C. albicans and C. tropicalis biofilms were higher than their respective levels in mixed biofilms across both pH values. Single C. tropicalis biofilms exhibited greater metabolic activity at both time points than C. albicans and mixed biofilms. While there were no notable pH or time-dependent differences in C. albicans and C. tropicalis monospecies biofilm formation, mixed biofilms displayed significantly higher biomass at pH 2.5. Ct also demonstrated pronounced filamentation within 24 h at pH 5.5. Scanning electron microscopy revealed cellular damage in mixed biofilms at pH 2.5; although, the biofilm structure was well developed within 24-48 h. Our findings indicate that yeasts isolated from IGB patients can form mono and polymicrobial biofilms under harsh conditions, with both species demonstrating biofilm viability at pH 2.5. Notably, C. tropicalis exhibited increased competitiveness in mixed biofilms under these conditions.</p>","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2025-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144552811","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":"Constitutive ALS3 expression in Candida albicans has differential effects on yeast-locked tet-NRG1 and brg1Δ strains.","authors":"Nicholas C Schena, Kassandra M Baker, Anna A Stark, Derek P Thomas, Ian A Cleary","doi":"10.1007/s12223-025-01288-y","DOIUrl":"https://doi.org/10.1007/s12223-025-01288-y","url":null,"abstract":"<p><p>The fungal pathogen Candida albicans produces numerous surface proteins involved in adhesion. Many of these adhesins are specific to different morphological forms. Strains that are unable to form hyphae are generally impaired in their ability to adhere to surfaces and to form biofilms. To better understand the function of one of these adhesins, Als3p, in the context of yeast-locked strains, we expressed ALS3 in strains with altered expression of one of two genes that are part of a regulatory circuit, BRG1 and NRG1. The mutant BRG1 and NRG1 strains we examined were phenotypically similar. We observed that ALS3 expression improved the adhesion of both strains to glass but that only one had altered biofilm forming ability, which was decreased.</p>","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144539713","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":"Application of a superpixel-based segmentation method to root micrographs for total fungal colonization rate estimation.","authors":"Laurie Paulin, Didier Techer","doi":"10.1007/s12223-025-01292-2","DOIUrl":"https://doi.org/10.1007/s12223-025-01292-2","url":null,"abstract":"<p><p>This work illustrates a novel application of a supervised superpixel-based segmentation method for root micrograph classification and total fungal colonization rate estimation. Two procedures relying on successive classifier application on different root micrographs or on the same micrograph but with an increasing number of labels to be assigned to each picture element category are compared to a reference grid-intersect count method. Finally, supervised classification with at least 16 labels on the same picture appears as a convenient method for obtaining rapid and confident colonization rate estimates. We suggest this kind of method may be easily and routinely implemented for research or educational purposes.</p>","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144539712","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":"Antimicrobial resistance mechanisms in non-tuberculous mycobacteria.","authors":"Esra Gül Tursun, Taylan Bozok, Gönül Aslan","doi":"10.1007/s12223-025-01287-z","DOIUrl":"https://doi.org/10.1007/s12223-025-01287-z","url":null,"abstract":"<p><p>Non-tuberculous mycobacteria (NTM) are pathogens that are widely distributed in the environment and cause increasing rates of human infections. High levels of antimicrobial resistance shown by these bacteria complicate infection management and limit treatment options. The complex structure of cell walls and features such as biofilm formation are responsible for intrinsic resistance in NTMs. Antimicrobial resistance can be explained by four basic mechanisms: (i) limitation of drug uptake, meaning antibiotic entry is limited due to the presence of a hydrophobic and low permeability cell wall and a small number of porin channels, (ii) enzymatic modification of antibiotics, (iii) target site modification, (iv) efflux pumps, which prevent drug accumulation by actively expelling antibiotics from the cell and reduce treatment efficacy. For effective management of NTM infections, detailed understanding of resistance mechanisms, development of species-specific treatment protocols, and discovery of new antimicrobial agents are of great importance. In this review, the mechanisms causing drug resistance in NTMs will be reviewed.</p>","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2025-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144527125","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":"Evaluation of andrographolide from Andrographis paniculata against drug-resistant and H₃₇Rv strains of Mycobacterium tuberculosis.","authors":"Jelin Vilvest, M C John Milton, Alex Yagoo, Kedike Balakrishna","doi":"10.1007/s12223-025-01291-3","DOIUrl":"https://doi.org/10.1007/s12223-025-01291-3","url":null,"abstract":"<p><p>Tuberculosis (TB) remains a major global health concern, particularly due to the emergence of multidrug-resistant (MDR) Mycobacterium tuberculosis strains. While previous studies have suggested andrographolide as a potential antimycobacterial agent based on in silico predictions, limited empirical evidence exists on its direct efficacy against MDR-TB. This study systematically evaluates the antimycobacterial activity of andrographolide through the microbroth dilution method against M. tuberculosis H₃₇Rv and three distinct MDR strains. The minimum inhibitory concentrations (MICs) were determined using Middlebrook 7H9 medium, with rifampicin and isoniazid as positive controls. Andrographolide completely inhibited M. tuberculosis H₃₇Rv at an MIC of 125 µg/mL, while MICs for MDR strains varied (500 µg/mL, 125 µg/mL, and 250 µg/mL for MDR-Isolates 1, 2, and 3, respectively). Unlike previous studies that primarily relied on computational docking models, our findings provide direct experimental validation of andrographolide's strain-specific efficacy, demonstrating its potential as a promising lead compound for anti-tubercular drug development. These results underscore the need for further preclinical investigations to explore its therapeutic applications in combating drug-resistant TB.</p>","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2025-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144527126","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":"Early and on-site detection of Ganoderma-induced basal stem rot in oil palm: using recombinase polymerase amplification-lateral flow assay.","authors":"M Amrutha Lakshmi, A I Bhat, P Malavika, M Indraja, B Kalyana Babu, A R N S Subbanna, K Suresh","doi":"10.1007/s12223-025-01270-8","DOIUrl":"https://doi.org/10.1007/s12223-025-01270-8","url":null,"abstract":"<p><p>Basal stem rot disease, caused by Ganoderma spp., is the major economic menace of oil palm cultivation. The disease begins with an asymptomatic phase, progresses to ambiguous foliar abnormalities, and culminates in stress malign fructification stage, the only conclusive visual evidence of infection. At this stage, the pathogen is well-established and resistant to curative measures, highlighting the critical need for early detection. The current study deployed recombinase polymerase amplification-lateral flow assay (RPA-LFA) for onsite and early detection of Ganoderma at the asymptomatic phase. The RPA reaction conditions were standardised with respect to the concentration of magnesium acetate and betaine concentration, incubation temperature as well as time. The assay was validated by analysing pure fungal DNA, pure plant DNA, and crude DNA extracted from palms showing varying degrees of disease severity collected from diverse sampling sources, including soil, stem, and roots. The detection system could detect Ganoderma with crude DNA extracted from asymptomatic palm roots. The method was highly sensitive, detecting as little as 10 pg/µL of Ganoderma DNA at 41 °C for 30 min. This assay, highly specific to Ganoderma, was validated across ten different species of Ganoderma. Further, there was no cross-reaction with ten other oil palm-related microbes/pathogens. To our knowledge, this is the first report to establish an RPA-LFA for the detection of Ganoderma-induced rots. The kit enables rapid and early detection of BSR samples at the point of care, at the asymptomatic stage, and is supportive of prompt and effective management strategies.</p>","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2025-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144316303","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":"Alteration of the intestinal microbiota associated with the development of nonalcoholic steatohepatitis and sarcopenia in SHRSP5/Dmcr.","authors":"Taketo Fukuoka, Shusei Yamamoto, Koki Honma, Moe Fujii, Hinako Nakayama, Sora Kirihara, Kazuyoshi Gotoh, Shuma Tsuji, Yuki Kawai, Haruka Tago, Yuka Kono, Kunihiro Sonoda, Kazuya Kitamori, Shogo Watanabe","doi":"10.1007/s12223-025-01283-3","DOIUrl":"https://doi.org/10.1007/s12223-025-01283-3","url":null,"abstract":"<p><p>Sarcopenia, characterized by skeletal muscle atrophy, was previously considered age-related; however, it is also associated with other diseases. Nonalcoholic fatty liver disease (NAFLD) is known to cause sarcopenia, and its complications have been reported to affect prognosis. The intestinal microbiota of patients with NAFLD or sarcopenia has been found to be altered compared to that of healthy individuals. However, the alterations that occur when both diseases coexist in humans or experimental animals remain unclear. Therefore, this study aimed to determine the intestinal microbiota changes associated with NAFLD with sarcopenia in SHRSP5/Dmcr rats at the time of concomitant disease. Fecal samples were collected from the rectum of SHRSP5/Dmcr rats fed a normal diet (non-NAFLD and non-Sarcopenia, n = 5) or a high-fat and high-cholesterol diet (NAFLD and Sarcopenia, n = 5) for 20 weeks, and subjected to 16S rRNA analysis. In the NAFLD and sarcopenia group, the diversity of the intestinal microbiota was reduced; further, the bacterial species reported in patients with NAFLD or sarcopenia were also changed. At the family level, the abundances of Akkermansiaceae, Bacteroidaceae, and Tannerellaceae were significantly higher whereas Ruminococcaceae and Lactobacillaceae were decreased in the NAFLD and sarcopenia group. At the genus level, the abundances of Akkermansia, Bacteroides, Ruminococcus, and Parabacteroides were significantly higher whereas the abundance of Lactobacillus was significantly decreased in the NAFLD and sarcopenia group. Overall, these findings help improve the existing understanding regarding the intestinal microbiota changes observed in conditions where NASH and sarcopenia co-occur.</p>","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144265823","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":"Functional validation of OsRPM1 as a positive regulator of bacterial blight resistance in rice via virus-induced gene silencing.","authors":"M Amrutha Lakshmi, Aditya Kulshreshtha, Kalyan K Mondal, Indranil Dasgupta, Aditya Tyagi, Sanjeev Kumar, N S Kalaivanan, S Mrutyunjaya, B Sreenayana, E R Rashmi, Thungri Ghoshal, Neelam Jagram, G K Challa, Chandra Mani","doi":"10.1007/s12223-025-01280-6","DOIUrl":"https://doi.org/10.1007/s12223-025-01280-6","url":null,"abstract":"<p><p>Bacterial blight (BB), caused by Xanthomonas oryzae pv. oryzae (Xoo), is a major constraint to rice production in humid tropical regions. In the search for new genetic sources of resistance, we focused on OsRPM1 (LOC Os12g30070.1), a rice gene encoding a coiled-coil nucleotide-binding leucine-rich repeat (CC-NB-LRR) protein, structurally similar to well-characterized resistance (R) proteins in Arabidopsis and other plant species. Although its role in rice immunity was previously uncharacterized, transcriptomic profiling revealed that OsRPM1 is significantly upregulated in a type III secretion system (T3SS)-dependent manner during infection with the virulent Xoo race 4, suggesting a pathogen-responsive defence function. To evaluate this, we employed virus-induced gene silencing (VIGS) to transiently suppress its expression in rice. Silencing OsRPM1 increased susceptibility to Xoo, resulting in more severe disease symptoms, reduced reactive oxygen species (ROS) accumulation, and impaired callose deposition; key defence responses linked to effective resistance. These findings demonstrate that OsRPM1 acts as a positive regulator of rice defence and support its potential as a candidate for broad-spectrum, durable resistance breeding.</p>","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144257729","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":"Site-specific community structure and plant growth-promoting properties of cultured actinomycetes associated with Deschampsia antarctica from Galindez Island, Antarctica.","authors":"Ivan Roman, Oleksandr Khylchuk, Victor Fedorenko, Oleksandr Gromyko","doi":"10.1007/s12223-025-01282-4","DOIUrl":"https://doi.org/10.1007/s12223-025-01282-4","url":null,"abstract":"<p><p>The rhizosphere microbiota plays a crucial role in plant growth and resilience, particularly in extreme environments such as Antarctica. This study explores the diversity and plant growth-promoting properties of actinomycetes associated with the rhizosphere of Deschampsia antarctica on Galindez Island, Maritime Antarctica, under varying microclimatic conditions and human-impacted sites. Using direct inoculation and selective pretreatment methods, a diverse array of actinomycete strains was isolated, representing genera such as Amorphoplanes, Embleya, Kribbella, Lentzea, Micromonospora, Nocardia, Rhodococcoides, Rhodococcus, Saccharopolyspora, Streptomyces, and Winogradskya. Sites influenced by human activity exhibited reduced actinomycete abundance and altered genus ratios compared to less disturbed areas. Among the isolated strains, many demonstrated the ability to produce siderophores for metals such as iron, nickel, copper, zinc, and manganese. Notably, five strains produced siderophores capable of binding all tested metals. Additionally, three strains exhibited the capacity to solubilize insoluble forms of both zinc and phosphorus while producing siderophores for all metals tested. Genomic analysis of one of these strains, namely, Streptomyces sp. Da 82-17, revealed an array of secondary metabolite gene clusters, including those for ectoine, paenibactin, and lidamycin, highlighting its significant biotechnological potential. Functional genomics identified genes encoding phytohormones, such as indole-3-acetic acid (IAA), and siderophores, which are critical for improving plant nutrient uptake and stress tolerance. These findings underscore the high biosynthetic potential of Antarctic actinomycetes for applications in agriculture, medicine, and biotechnology. Further research into microbiota from both human-impacted and pristine regions on Galindez Island will enhance understanding of microbial adaptation and inform strategies to mitigate anthropogenic impacts, preserving the unique Antarctic ecosystem.</p>","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2025-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144247257","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":"Repurposing of quinine as an antifungal antibiotic: Identification of molecular targets in Candida albicans.","authors":"Sargun Basrani, Shivani Patil, Sayali Chougule, Tanjila Kotalagi, Shivanand Yankanchi, Sankunny Mohan Karuppayil, Ashwini K Jadhav","doi":"10.1007/s12223-025-01281-5","DOIUrl":"https://doi.org/10.1007/s12223-025-01281-5","url":null,"abstract":"<p><p>Quinine, a component of the bark of the cinchona tree, is commonly used to treat malaria. The present study focused on the identification of anti-Candida albicans activity of quinine and its mechanism of action. Quinine showed planktonic growth inhibitory activity at 0.5 mg/mL and fungicidal activity at 4 mg/mL concentration. Time-dependent killing of C. albicans cells was seen after the treatment of quinine at 4 mg/mL concentration. The MIC₅₀ of quinine against yeast to hyphal morphogenesis, adhesion and biofilm formation of C. albicans were observed at 0.25 mg/mL, 1 mg/mL and 0.031 mg/mL, respectively. Scanning electron microscopy analysis of architecture of quinine treated C. albicans biofilm at 2 mg/mL concentration revealed that biofilm formation was significantly inhibited by the treatment of quinine. Quinine also able to inhibit ergosterol synthesis in C. albicans at the concentration range of 2 to 0.062 mg/mL. Quinine could arrest the cell cycle of C. albicans G2/M and S phase at 0.5 mg/mL. qRT-PCR study has demonstrated that the expression of SOD2 and CAT genes in C. albicans was upregulated by 5-fold and 6-fold, respectively in the presence of quinine at 0.5 mg/mL. To check the in vivo antifungal efficacy of quinine, an experiment was carried out in silkworm animal model and it was observed that quinine exhibits antifungal potential against C. albicans pathogenesis. These findings suggest the potential of quinine as a repurposed agent against C. albicans infections.</p>","PeriodicalId":12346,"journal":{"name":"Folia microbiologica","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2025-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144247256","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}