{"title":"Enhancement of the structure and biochemical function of cyclomaltodextrinase from the Anoxybacillus flavithermus ZNU-NGA with site-directed mutagenesis.","authors":"Ziba Mirzaee, Vahab Jafarian, Khosrow Khalifeh","doi":"10.1007/s10123-024-00554-2","DOIUrl":"10.1007/s10123-024-00554-2","url":null,"abstract":"<p><p>This study was conducted to examine the role of the central domain of cyclomaltodextrinase in terms of stability, substrate specificity, becoming dodecameric form, and enzyme activity. To this end, H403R/L309V double-point mutation and T280Q single-point mutation were performed at the central domain and (β/α)8-barrel. The results indicated that the activity of the H403R/L309V mutant at the optimal pH and temperature increased by about 25% and 40%, respectively. Plus, the irreversible thermal inactivation of the H403R/L309V mutant at 60 °C and 160 min was approximately twice of the enzyme without mutation. Both mutants underwent significant structural change relative to the wild enzyme and subsequently a significant catalytic activity. However, the catalytic efficiency (kcat/Km) of the H403R/L309V mutant increased in the presence of beta- and gamma-cyclomaltodextrin substrates compared to the wild enzyme and T280Q mutant. As a result, by applying the L309V mutant and given the smaller size of the valine, leucine spatial inhibition in the wild protein seems to decline, and also it facilitates the substrate access to active site amino acids. Moreover, as gamma substrate is larger, eliminating the effect of spatial inhibition on this substrate has a greater effect on improving the catalytic activity of this enzyme.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":"461-471"},"PeriodicalIF":2.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141558756","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":"Metataxonomic characterization of the microbial present in the anaerobic digestion of turkey litter waste with the addition of two inocula: allochthonous and commercial.","authors":"Janaina Iltchenco, Mariana Dalsoto Smiderle, Juliano Gaio, Flaviane Eva Magrini, Suelen Paesi","doi":"10.1007/s10123-024-00561-3","DOIUrl":"10.1007/s10123-024-00561-3","url":null,"abstract":"<p><p>Turkey litter waste is lignocellulosic waste that can be sustainably used as an energy source through anaerobic digestion (AD). The 16S ribosomal RNA technique helps to unravel microbial diversity and predominant metabolic pathways. The assays were performed in 600-mL-glass bottles with 400 mL volume, for 60 days at 37 °C. The study evaluated the physicochemical parameters, the composition of the microbiota, and the functional inference in AD of different concentrations of turkey litter (T) using two inocula: granular inoculum (S) and commercial inoculum (B). The highest accumulated methane production (633 mL CH4·L<sup>-1</sup>) was observed in the test containing 25.5 g VS·L<sup>-1</sup> of turkey litter with the addition of the two inocula (T3BS). In tests without inoculum (T3) and with commercial inoculum (T3B), there was an accumulation of acids and consequent inhibition of methane production 239 mL CH<sub>4</sub>·L<sup>-1</sup> and 389 mL CH<sub>4</sub>·L<sup>-1</sup>, respectively. Bacteroidota, Firmicutes, and Actinobacteria were the main phyla identified. The presence of archaea Methanobacterium, Methanocorpusculum, and Methanolinea highlighted the hydrogenotrophic metabolic pathway in T3BS. Functional prediction showed enzymes involved in three metabolic pathways in turkey litter biodigestion: acetotrophic, hydrogenotrophic, and methylotrophic methanogenesis. The predominant hydrogenotrophic pathway can be observed by analyzing the microbiota, archaea involved in this specific pathway, genes involved, and relative acid consumption for T3S and T3BS samples with higher methane production. Molecular tools help to understand the main groups of microorganisms and metabolic pathways involved in turkey litter AD, such as the use of different inocula, allowing the development of strategies for the sustainable disposal of turkey litter.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":"539-551"},"PeriodicalIF":2.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141748073","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}
Heesang Hong, Hye-Jin Kim, Hyun-Jun Kim, Cheorun Jo
{"title":"Investigation of different cold adaptation abilities in Salmonella enterica serotype Typhimurium strains using extracellular metabolomic approach.","authors":"Heesang Hong, Hye-Jin Kim, Hyun-Jun Kim, Cheorun Jo","doi":"10.1007/s10123-024-00556-0","DOIUrl":"10.1007/s10123-024-00556-0","url":null,"abstract":"<p><p>This study explored the extracellular metabolomic responses of three different Salmonella enterica serotype Typhimurium (S. Typhimurium) strains-ATCC 13311 (STy1), NCCP 16964 (STy4), and NCCP 16958 (STy8)-cultured at refrigeration temperatures. The objective was to identify the survival mechanisms of S. Typhimurium under cold stress by analyzing variations in their metabolomic profiles. Qualitative and quantitative assessments identified significant metabolite alterations on day 6, marking a critical inflection point. Key metabolites such as trehalose, proline, glycerol, and tryptophan were notably upregulated in response to cold stress. Through multivariate analyses, the strains were distinguished using three metabolites-4-aminobutyrate, ethanol, and uridine-as potential biomarkers, underscoring distinct metabolic responses to refrigeration. Specifically, STy1 exhibited unique adaptive capabilities through enhanced metabolism of betaine and 4-aminobutyrate. These findings highlight the variability in adaptive strategies among S. Typhimurium strains, suggesting that certain strains may possess more robust metabolic pathways for enhancing survival in refrigerated conditions.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":"447-460"},"PeriodicalIF":2.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141558674","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}
Ao-Bo Tan, Hui Wang, Jiang-Tao Ji, Han-Yue Yao, Hong-Yan Tang
{"title":"Hg<sup>2+</sup> removal characteristics of a strain of mercury-tolerant bacteria screened from heavy metal-contaminated soil in a molybdenum-lead mining area.","authors":"Ao-Bo Tan, Hui Wang, Jiang-Tao Ji, Han-Yue Yao, Hong-Yan Tang","doi":"10.1007/s10123-024-00559-x","DOIUrl":"10.1007/s10123-024-00559-x","url":null,"abstract":"<p><p>In this study, the mercury-tolerant strain LTC105 was isolated from a contaminated soil sample collected from a molybdenum-lead mine in Luanchuan County, Henan Province, China. The strain was shown to be highly resistant to mercury, with a minimum inhibitory concentration (MIC) of 32 mg·L<sup>-1</sup>. After a 24-h incubation in LB medium with 10 mg·L<sup>-1</sup> Hg<sup>2+</sup>, the removal, adsorption, and volatilization rates of Hg<sup>2+</sup> were 97.37%, 7.3%, and 90.07%, respectively, indicating that the strain had significant influence on mercury removal. Based on the results of Fourier infrared spectroscopy (FTIR) and scanning electron microscopy (SEM), the investigation revealed that the primary function of LTC105 was to encourage the volatilization of mercury. The LTC105 strain also showed strong tolerance to heavy metals such as Mn<sup>2+</sup>, Zn<sup>2+</sup>, and Pb<sup>2+</sup>. According to the results of the soil incubation test, the total mercury removal rate of the LTC105 inoculation increased by 16.34% when the initial mercury concentration of the soil was 100 mg·L<sup>-1</sup> and by 62.28% when the initial mercury concentration of the soil was 50 mg·kg<sup>-1</sup>. These findings indicate that LTC105 has certain bioremediation ability for Hg-contaminated soil and is a suitable candidate strain for microbial remediation of heavy metal-contaminated soil in mining areas.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":"525-538"},"PeriodicalIF":2.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141723625","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}
Tanjila C Gavandi, Sargun T Basrani, Sayali A Chougule, Shivani B Patil, Omkar S Nille, Govind B Kolekar, Shivanand R Yankanchi, S Mohan Karuppayil, Ashwini K Jadhav
{"title":"Vidarabine as a novel antifungal agent against Candida albicans: insights on mechanism of action.","authors":"Tanjila C Gavandi, Sargun T Basrani, Sayali A Chougule, Shivani B Patil, Omkar S Nille, Govind B Kolekar, Shivanand R Yankanchi, S Mohan Karuppayil, Ashwini K Jadhav","doi":"10.1007/s10123-024-00565-z","DOIUrl":"10.1007/s10123-024-00565-z","url":null,"abstract":"<p><p>Around 1.5 million mortality cases due to fungal infection are reported annually, posing a massive threat to global health. However, the effectiveness of current antifungal therapies in the treatment of invasive fungal infections is limited. Repurposing existing antifungal drugs is an advisable alternative approach for enhancing their effectiveness. This study evaluated the antifungal efficacy of the antiviral drug vidarabine against Candida albicans ATCC 90028. Antifungal susceptibility testing was performed by microbroth dilution assay and further processed to find the minimum fungicidal concentration. Investigation on probable mode of vidarabine action against C. albicans was assessed by using the ergosterol reduction assay, reactive oxygen species (ROS) accumulation, nuclear condensation, and apoptosis assay. Results revealed that C. albicans was susceptible to vidarabine action and exhibited minimum inhibitory concentration at 150 µg/ml. At a concentration of 300 µg/ml, vidarabine had fungicidal activity against C. albicans. 300 µg/ml vidarabine-treated C. albicans cells demonstrated 91% reduced ergosterol content. Annexin/FITC/PI assay showed that vidarabine (150 µg/ml) had increased late apoptotic cells up to 31%. As per the fractional inhibitory concentration index, vidarabine had synergistic activity with fluconazole and caspofungin against this fungus. The mechanism underlying fungicidal action of vidarabine was evaluated at the intracellular level, and probably because of increased nuclear condensation, enhanced ROS generation, and cell cycle arrest. In conclusion, this data is the first to report that vidarabine has potential to be used as a repurposed antifungal agent alone or in combination with standard antifungal drugs, and could be a quick and safe addition to existing therapies for treating fungal infections.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":"589-602"},"PeriodicalIF":2.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141912754","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":"Anti-microbial, anti-biofilm, and efflux pump inhibitory effects of ellagic acid-bonded magnetic nanoparticles against Escherichia coli isolates.","authors":"Fatemeh Norouzalinia, Leila Asadpour, Masoud Mokhtary","doi":"10.1007/s10123-024-00560-4","DOIUrl":"10.1007/s10123-024-00560-4","url":null,"abstract":"<p><p>The spread of microbial resistance is a threat to public health. In this study, the anti-microbial, anti-biofilm, and efflux pump inhibitory effects of ellagic acid-loaded magnetic nanoparticles (Fe<sub>3</sub>O<sub>4</sub>NPs@EA) against beta-lactamase producing Escherichia coli isolates have been investigated. The effects of Fe<sub>3</sub>O<sub>4</sub> NPs@EA on the growth inhibition of E. coli isolates were determined by disc diffusion method and determining the minimum inhibitory concentration was done using broth micro-dilution method. The anti-biofilm effect of nanoparticles was investigated using the microplate method. The efflux pump inhibitory effect of nanoparticles was investigated using cart-wheel method and by investigating the effect of nanoparticles on acrB and tolC genes expression levels. Fe<sub>3</sub>O<sub>4</sub> NPs@EA showed anti-bacterial effects against test bacteria, and the MIC of these nanoparticles varied from 0.19 to 1.56 mg/mL. These nanoparticles caused a 43-62% reduction in biofilm formation of test bacteria compared to control. Furthermore, efflux pump inhibitory effect of these nanoparticles was confirmed at a concentration of 1/8 MIC, and the expression of acrB and tolC genes decreased in bacteria treated with 1/4 MIC Fe<sub>3</sub>O<sub>4</sub> NPs@EA. According to the results, the use of nanoparticles containing ellagic acid can provide a basis for the development of new treatments against drug-resistant E. coli. This substance may improve the concentration of antibiotics in the bacterial cell and increase their effectiveness by inhibiting the efflux in E. coli isolates.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":"563-573"},"PeriodicalIF":2.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141893337","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":"Effects of grassland degradation on diversity of arbuscular mycorrhizal fungi of a pioneer plant.","authors":"Qiqi Han, Zichao Li, Yingjie Jiang, Zhuo Zhang, Yuao Qin, Zhongkuan Liu, Guixia Liu","doi":"10.1007/s10123-024-00564-0","DOIUrl":"10.1007/s10123-024-00564-0","url":null,"abstract":"<p><p>Arbuscular mycorrhizal fungi (AMF) are obligate symbionts that engage in crucial interactions with plants, playing a vital role in grassland ecology. Our study focuses on the pioneer plant Agropyron cristatum, and we collected soil samples from four degraded grasslands in Yudaokou to investigate the response of community composition to the succession of degraded grasslands. We measured the vegetation status, soil physical and chemical properties, AMF colonization, and spore density in different degraded grasslands. High-throughput sequencing was employed to analyze AMF in soil samples. Correlations among community composition, soil characteristics, and plant factors were studied using principal component and regression analyses. The distribution of AMF in grasslands exhibited variation with different degrees of degradation, with Glomus, Scutellospora, and Diversispora being the dominant genera. The abundance of dominant genera in AMF also varied, showing a gradual increase in the relative abundance of the genus Diversispora with higher degradation levels. AMF diversity decreased from 27.7% to 12.4% throughout the degradation process. Among 180 samples of Agropyron cristatum plants, AMF hyphae and vesicles displayed the highest infection status in non-degraded grasslands and the lowest in severely degraded ones. Peak AMF spore production occurred in August, with maximum values in the 0-10-cm soil layer, and the highest spore densities were found in lightly degraded grasslands. Apart from pH, soil factors exhibited a positive correlation with AMF infection during grassland degradation. Furthermore, changes in AMF community composition were jointly driven by vegetation and soil characteristics, with vegetation coverage and soil organic carbon significantly impacting AMF distribution. Significant differences in AMF variables (spore number and diversity index) were also observed at different soil depths. Grassland successional degradation significantly influences AMF community structure and composition. Our future focus will be on understanding response mechanisms and implementing improvement methods for AMF during grassland degradation and subsequent restoration efforts.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":"603-621"},"PeriodicalIF":2.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141916678","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}
Matlou D Semenya, Adebowale E Aladejana, Sizwe I Ndlovu
{"title":"Characterization of susceptibility patterns and adaptability of the newly emerged Candida auris.","authors":"Matlou D Semenya, Adebowale E Aladejana, Sizwe I Ndlovu","doi":"10.1007/s10123-024-00563-1","DOIUrl":"10.1007/s10123-024-00563-1","url":null,"abstract":"<p><p>The emergence of Candida auris has caused a major concern in the public health worldwide. This novel fungus is characterized by its multidrug resistance profile, ability to thrive in harsh and stressful conditions, as well as high temperatures and salt concentrations, persistence on hospital surfaces, causing nosocomial infections and outbreaks, and unique fitness properties. Here, we study the antifungal susceptibility patterns, thermotolerance, and halotolerance of 15 putative C. auris clinical isolates from Inkosi Albert Academic Hospital, Durban, South Africa. Five of the C. auris isolates showed resistance to all three antifungals (fluconazole, amphotericin B, and micafungin) and were selected for characterization of their adaptability mechanisms. Four of the tested multidrug-resistant C. auris isolates (C. auris strain F25, C. auris strain F276, C. auris F283, and C. auris M153) showed good growth when exposed to high temperature (42 °C) and salinity (10% NaCl) conditions whereas one isolate (C. auris F65) showed moderate growth under these conditions. Candida parapsilosis showed poor growth whereas C. albicans no growth under these conditions. The five C. auris strains were positive for all the adaptive features.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":"575-587"},"PeriodicalIF":2.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11906518/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141897433","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Harun Hizlisoy, Adalet Dishan, Ilknur Karaca Bekdik, Mukaddes Barel, Kursat Koskeroglu, Yasin Ozkaya, Oznur Aslan, Omer Tolga Yilmaz
{"title":"Candida albicans in the oral cavities of pets: biofilm formation, putative virulence, antifungal resistance profiles and classification of the isolates.","authors":"Harun Hizlisoy, Adalet Dishan, Ilknur Karaca Bekdik, Mukaddes Barel, Kursat Koskeroglu, Yasin Ozkaya, Oznur Aslan, Omer Tolga Yilmaz","doi":"10.1007/s10123-024-00552-4","DOIUrl":"10.1007/s10123-024-00552-4","url":null,"abstract":"<p><p>The study aimed to investigate Candida albicans presence, antifungal resistance, biofilm formation, putative virulence genes, and molecular characterization in oral samples of dogs and cats. A total of 239 oral samples were collected from cats and dogs of various breeds and ages at Erciyes University, Faculty of Veterinary Medicine Clinics, between May 2017 and April 2018. Among 216 isolates obtained, 15 (6.95%) were identified as C. albicans, while 8 (3.7%) were non-albicans Candida species. Antifungal susceptibility testing revealed sensitivities to caspofungin, fluconazole, and flucytosine in varying proportions. Molecular analysis indicated the presence of fluconazole and caspofungin resistance genes in all C. albicans isolates. Additionally, virulence genes ALS1, HWP1, and HSP90 showed variable presence. Biofilm formation varied among isolates, with 46.7% strong, 33.3% moderate, and 20% weak producers. PCA analysis categorized isolates into two main clusters, with some dog isolates grouped separately. The findings underscore the significance of oral care and protective measures in pets due to C. albicans prevalence, biofilm formation, virulence factors, and antifungal resistance in their oral cavity, thereby aiding clinical diagnosis and treatment in veterinary medicine.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":"423-435"},"PeriodicalIF":2.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141491859","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}
Cheng-Hsun Ho, Tsung-Ying Yang, Sung-Pin Tseng, Pei-Yi Su
{"title":"Antimicrobial efficacy and amino acid substitutions associated with susceptibility to the tellurium compound AS101 against Haemophilus influenzae and Haemophilus parainfluenzae.","authors":"Cheng-Hsun Ho, Tsung-Ying Yang, Sung-Pin Tseng, Pei-Yi Su","doi":"10.1007/s10123-024-00558-y","DOIUrl":"10.1007/s10123-024-00558-y","url":null,"abstract":"<p><p>The tellurite toxicity in Haemophilus influenzae and H. parainfluenzae remains unclear. To understand the potential of tellurite as a therapeutic option for these bacteria, we investigated the antimicrobial efficacy of AS101, a tellurium compound, against H. influenzae and H. parainfluenzae and the molecular basis of their differences in AS101 susceptibility. Through broth microdilution, we examined the minimum inhibitory concentration (MIC) of AS101 in 51 H. influenzae and 28 H. parainfluenzae isolates. Whole-genome sequencing was performed on the H. influenzae isolates to identify genetic variations associated with AS101 susceptibility. The MICs of AS101 were ≦ 4, 16-32, and ≧ 64 μg/mL in 9 (17.6%), 12 (23.5%), and 30 (58.8%) H. influenzae isolates, respectively, whereas ≦ 0.5 μg/mL in all H. parainfluenzae isolates, including multidrug-resistant isolates. Time-killing kinetic assay and scanning electron microscopy revealed the in vitro bactericidal activity of AS101 against H. parainfluenzae. Forty variations in nine tellurite resistance-related genes were associated with AS101 susceptibility. Logistic regression, receiver operator characteristic curve analysis, Venn diagram, and protein sequence alignment indicated that Val195Ile substitution in TerC, Ser93Gly in Gor (glutathione reductase), Pro44Ala/Ala50Pro in NapB (nitrate reductase), Val307Leu in TehA (tellurite resistance protein), Cys105Arg in CysK (cysteine synthase), and Thr364Ser in Csd (Cysteine desulfurase) were strongly associated with reduced AS101 susceptibility, whereas Ser155Pro in TehA with increased AS101 susceptibility. In conclusions, the antimicrobial efficacy of AS101 is high against H. parainfluenzae but low against H. influenzae. Genetic variations and corresponding protein changes relevant to AS101 non-susceptibility in H. influenzae were identified.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":"473-484"},"PeriodicalIF":2.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141579645","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}