Polish journal of microbiology最新文献

{"title":"Cloning Cellulase Genes from Victoria Falls Rainforest Decaying Logs Metagenome.","authors":"Makhosazana Nyathi, Zephaniah Dhlamini, Thembekile Ncube","doi":"10.33073/pjm-2024-029","DOIUrl":"10.33073/pjm-2024-029","url":null,"abstract":"<p><p>The Victoria Falls rainforest is a protected site whose forest floors harbor a host of cellulolytic microorganisms involved in biomass degradation. This study collected decaying logs and soil from the rainforest for bioprospecting cellulases from their metagenomes. Metagenomic DNA was isolated from the compound sample. Degenerate cellulase primers were used to amplify cellulase genes in the metagenome. The resulting amplicons cloned into Z-competent <i>Escherichia coli</i> DH5α were analyzed by functional screening for the production of cellulase extracellularly. Functional screening of the clones resulted in one clone (Clone-i) testing positive for extracellular cellulase production. Submerged fermentation of Clone-i was carried out for cellulase production. The cellulases were characterized to determine their activity's optimum pH and temperature. The diversity of the cellulases produced by Clone-i was determined. Clone-i's optimum enzyme activity was observed after 72 hours of incubation at 50°C and pH 5. Clone-i produced 80% more exoglucanases as compared to endoglucanases. The cellulolytic Clone-i' isolate shows Victoria Falls rainforest's potential as an enzyme bioprospecting site, reflecting that metagenomics is a valuable tool in microbial ecology.</p>","PeriodicalId":94173,"journal":{"name":"Polish journal of microbiology","volume":" ","pages":"343-348"},"PeriodicalIF":0.0,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11398271/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141794428","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Guanylate-Binding Protein 1 (GBP1) Enhances IFN-α Mediated Antiviral Activity against Hepatitis B Virus Infection.","authors":"Yadi Li, Haiying Luo, Xiaoxia Hu, Jiaojiao Gong, Guili Tan, Huating Luo, Rui Wang, Hao Pang, Renjie Yu, Bo Qin","doi":"10.33073/pjm-2024-021","DOIUrl":"10.33073/pjm-2024-021","url":null,"abstract":"<p><p>Interferon-alpha (IFN-α) is a first-line drug for treating chronic hepatitis B (CHB). Guanylate-binding protein 1 (GBP1) is one of the interferon-stimulating factors, which participates in the innate immunity of the host and plays an antiviral and antibacterial role. In this study, we explored how GBP1 is involved in IFN-α antiviral activity against HBV. Before being gathered, HepG2-NTCP and HepG2 2.15 cells were transfected with the wild-type hGBP1 plasmid or si-GBP1, respectively, and followed by stimulation with Peg-IFNα-2b. We systematically explored the role of GBP1 in regulating HBV infection in cell models. Additionally, we also examined GBP1 levels in CHB patients. GBP1 activity increased, and its half-life was prolonged after HBV infection. Overexpression of GBP1 inhibited the production of HBsAg and HBeAg, as well as HBs protein and HBV total RNA levels, whereas silencing of GBP1 inhibited its ability to block viral infections. Interestingly, overexpressing GBP1 co-treatment with Peg-IFNα-2b further increased the antiviral effect of IFN-α, while GBP1 silencing co-treatment with Peg-IFNα-2b partly restored its inhibitory effect on HBV. Mechanistically, GBP1 mediates the anti-HBV response of Peg-IFNα-2b by targeting HBs. Analysis of clinical samples revealed that GBP1 was elevated in CHB patients and increased with Peg-IFNα-2b treatment, while GBP1 showed good stability in the interferon response group. Our study demonstrates that GBP1 inhibits HBV replication and promotes HBsAg clearance. It is possible to achieve antiviral effects through the regulation of IFN-α induced immune responses in response to HBV.</p>","PeriodicalId":94173,"journal":{"name":"Polish journal of microbiology","volume":"73 2","pages":"217-235"},"PeriodicalIF":0.0,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11192456/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141437980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Halogenated Secondary Metabolites from Higher Plants: Potent Drug Candidates for Chikungunya Using <i>in silico</i> Approaches.","authors":"Sushil Kumar, Nidhi Joshi, Gourav Choudhir, Sakshi Sharma, Abhay Tiwari, Sulaiman Ali Alharbi, Saleh Alfarraj, Mohammad Javed Ansari","doi":"10.33073/pjm-2024-020","DOIUrl":"10.33073/pjm-2024-020","url":null,"abstract":"<p><p>Chikungunya virus (CHIKV) causes a debilitating fever and joint pain, with no specific antiviral treatment available. Halogenated secondary metabolites from plants are a promising new class of drug candidates against chikungunya, with unique properties that make them effective against the virus. Plants produce these compounds to defend themselves against pests and pathogens, and they are effective against a wide range of viruses, including chikungunya. This study investigated the interactions of halogenated secondary metabolites with nsP2pro, a therapeutic target for CHIKV. A library of sixty-six halogenated plant metabolites screened previously for ADME properties was used. Metabolites without violation of Lipinski's rule were docked with nsP2pro using AutoDock Vina. To find the stability of the pipoxide chlorohydrin-nsP2pro complex, the GROMACS suite was used for MD simulation. The binding free energy of the ligand-protein complex was computed using MMPBSA. Molecular docking studies revealed that halogenated metabolites interact with nsP2pro, suggesting they are possible inhibitors. Pipoxide chlorohydrin showed the greatest affinity to the target. This was further confirmed by the MD simulations, surface accessible area, and MMPBSA studies. Pipoxide chlorohydrin, a halogenated metabolite, was the most potent against nsP2pro in the survey.</p>","PeriodicalId":94173,"journal":{"name":"Polish journal of microbiology","volume":"73 2","pages":"207-215"},"PeriodicalIF":0.0,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11192229/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141437981","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Potential Usefulness of IgA for the Early Detection of SARS-CoV-2 Infection: Comparison With IgM.","authors":"Pei Wang","doi":"10.33073/pjm-2024-019","DOIUrl":"10.33073/pjm-2024-019","url":null,"abstract":"<p><p>Serological testing can be a powerful complementary approach to achieve timely diagnosis of severe acute respiratory coronavirus 2 (SARS-CoV-2) infection, along with nucleic acid detection. Immunoglobulin (Ig) A antibodies are less frequently utilized to detect SARS-CoV-2 infection than IgM and IgG antibodies, even though IgA antibodies play an important role in protective immunity against SARS-CoV-2. This review discusses the differences in kinetics and assay performance between IgA and IgM antibodies and the factors influencing antibody responses. It highlights the potential usefulness of analyzing IgA antibodies for the early detection of SARS-CoV-2 infection. The early appearance of IgA and the high sensitivity of IgA-based immunoassays can aid in diagnosing coronavirus disease 2019. However, because of cross-reactivity, it is important to recognize the only moderate specificity of the early detection of SARS-CoV-2 IgA antibodies against spike antigens. Either the analysis of antibodies targeting the nucleocapsid antigen or a combination of antibodies against the nucleocapsid and spike antigens may strengthen the accuracy of serological evaluation.</p>","PeriodicalId":94173,"journal":{"name":"Polish journal of microbiology","volume":"73 2","pages":"123-130"},"PeriodicalIF":0.0,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11192524/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141437983","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Negative Pressure Level and Effects on Bacterial Growth Kinetics in an <i>in vitro</i> Wound Model.","authors":"Adam Bobkiewicz, Wojciech Francuzik, Amy Martinkosky, Maciej Borejsza-Wysocki, Witold Ledwosinski, Krzysztof Szmyt, Tomasz Banasiewicz, Lukasz Krokowicz","doi":"10.33073/pjm-2024-018","DOIUrl":"10.33073/pjm-2024-018","url":null,"abstract":"<p><p>Negative Pressure Wound Therapy (NPWT) has been widely adopted in wound healing strategies due to its multimodal mechanism of action. While NPWT's positive impression on wound healing is well-established, its effect on bacterial load reduction remains equivocal. This study investigates NPWT's efficacy in reducing bioburden using an <i>in vitro</i> porcine skin model, focusing on the impact of <i>Staphylococcus aureus</i> and <i>Staphylococcus epidermidis</i>. Custom-made negative pressure chambers were employed to apply varying negative pressures. Porcine skin was cut into 5 × 5 cm squares and three standardized wounds of 6 mm each were created using a biopsy punch. Then, wounds were infected with <i>S. aureus</i> and <i>S. epidermidis</i> bacterial suspensions diluted 1:10,000 to obtain a final concentration of 1.5 × 10⁴ CFU/ml and were placed in negative pressure chambers. After incubation, bacterial counts were expressed as colony-forming units (CFU) per ml. For <i>S. aureus</i> at 120 hours, the median CFU, mean area per colony, and total growth area were notably lower at -80 mmHg when compared to -250 mmHg and -50 mmHg, suggesting an optimal negative pressure for the pressure-dependent inhibition of the bacterial proliferation. While analyzing <i>S. epidermidis</i> at 120 hours, the response to the negative pressure was similar but less clear, with the minor CFU at -100 mmHg. The influence of intermittent negative pressure on the <i>S. epidermidis</i> growth showed notably lower median CFU with the interval therapy every hour compared to the <i>S. aureus</i> control group. This study contributes valuable insights into NPWT's influence on the bacterial load, emphasizing the need for further research to reformulate its role in managing contaminated wounds.</p>","PeriodicalId":94173,"journal":{"name":"Polish journal of microbiology","volume":"73 2","pages":"199-206"},"PeriodicalIF":0.0,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11192228/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141437982","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biological Characteristics of the Mycelium and Optimization of the Culture Medium for <i>Phallus dongsun</i>.","authors":"Chao Kang, Xuan Zheng, Wankun Wang, Weijun Zeng, Jing Wang, Zhongxuan Liu, Ling Yang, Fang Wang, Yan Zhu","doi":"10.33073/pjm-2024-022","DOIUrl":"10.33073/pjm-2024-022","url":null,"abstract":"<p><p>This study aimed to elucidate the influence of various culture medium components, including carbon sources, nitrogen sources, inorganic salts, suspension agents, and temperature, on the mycelial growth characteristics of <i>Phallus dongsun</i>. Employing single-factor experiments and response surface methodology within glass Petri dishes, the research identified that carrot powder, soybean powder, and ZnSO₄ notably enhanced the proliferation of aerial mycelium, significantly augmenting the growth rate of <i>P. dongsun</i> mycelium. The resultant mycelium was observed to be dense, robust, and fluffy in texture. In particular, ZnSO₄ markedly accelerated the mycelium growth rate. Furthermore, xanthan gum was found to effectively modulate the medium's viscosity, ensuring a stable suspension and facilitating nutrient equilibrium. The optimal cultivation temperature was determined to be 25°C, with mycelial growth ceasing below 5°C and mycelium perishing at temperatures exceeding 35°C. The optimal medium composition was established as follows: wheat starch 5 g/l, carrot powder 5 g/l, soybean powder 7.50 g/l, glucose 10 g/l, ZnSO₄ 0.71 g/l, NH₄Cl 0.68 g/l, xanthan gum 0.5 g/l, and agar 20 g/l. Under these optimized conditions, the mycelium of <i>P. dongsun</i> exhibited a rapid growth rate (1.04 ± 0.14 mm/day), characterized by a thick, dense, and well-developed structure. This investigation provides a theoretical foundation for the conservation, strain selection, and breeding of <i>P. dongsun</i>.</p>","PeriodicalId":94173,"journal":{"name":"Polish journal of microbiology","volume":"73 2","pages":"237-252"},"PeriodicalIF":0.0,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11192555/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141437978","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Establishment of a Nucleic Acid Detection Method for Norovirus GII.2 Genotype Based on RT-RPA and CRISPR/Cas12a-LFS.","authors":"Ting Wang, Hao Zeng, Jie Kang, Lanlan Lei, Jing Liu, Yuhong Zheng, Weidong Qian, Cheng Fan","doi":"10.33073/pjm-2024-023","DOIUrl":"10.33073/pjm-2024-023","url":null,"abstract":"<p><p>To establish a rapid detection method for norovirus GII.2 genotype, this study employed reverse transcription recombinase polymerase amplification (RT-RPA) combined with CRISPR/Cas12a and lateral flow strip (RT-RPA-Cas12a-LFS). Here, the genome of norovirus GII.2 genotype was compared to identify highly conserved sequences, facilitating the design of RT-RPA primers and crRNA specific to the conserved regions of norovirus GII.2. Subsequently, the reaction parameters of RT-RPA were optimized and evaluated using agar-gel electrophoresis and LFS. The results indicate that the conserved sequences of norovirus GII.2 were successfully amplified through RT-RPA at 37°C for 25 minutes. Additionally, CRISPR/Cas12a-mediated cleavage detection was achieved through LFS at 37°C within 10 minutes using the amplification products as templates. Including the isothermal amplification reaction time, the total time is 35 minutes. The established RT-RPA-Cas12a-LFS method demonstrated specific detection of norovirus GII.2, yielding negative results for other viral genomes, and exhibited an excellent detection limit of 10 copies/μl. The RT-RPA-Cas12a-LFS method was further compared with qRT-PCR by analyzing 60 food-contaminated samples. The positive conformity rate was 100%, the negative conformity rate was 95.45%, and the overall conformity rate reached 98.33%. This detection method for norovirus GII.2 genotype is cost-effective, highly sensitive, specific, and easy to operate, offering a promising technical solution for field-based detection of the norovirus GII.2 genotype.</p>","PeriodicalId":94173,"journal":{"name":"Polish journal of microbiology","volume":"73 2","pages":"253-262"},"PeriodicalIF":0.0,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11192556/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141437979","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of the Class 1 Integrons, Carbapenemase Genes and Biofilm Formation Genes Occurrence in <i>Acinetobacter baumannii</i> Clinical Isolates.","authors":"Yu Xiu, Yueru Dai, Shasha Yin, Quhao Wei","doi":"10.33073/pjm-2024-017","DOIUrl":"10.33073/pjm-2024-017","url":null,"abstract":"<p><p><i>Acinetobacter baumannii</i> is a non-fermentative Gram-negative bacterium that can cause nosocomial infections in critically ill patients. Carbapenem-resistant <i>A. baumannii</i> (CRAB) has spread rapidly in clinical settings and has become a key concern. The main objective of this study was to identify the distribution of integrons and biofilm-formation-related virulence genes in CRAB isolates. A total of 269 <i>A. baumannii</i> isolates (219 isolates of CRAB and 50 isolates of carbapenem-sensitive <i>A. baumannii</i> (CSAB)) were collected. Carbapenemase genes (<i>bla</i> _KPC, <i>bla</i> _VIM, <i>bla</i> _IMP, <i>bla</i> _NDM, and <i>bla</i> _OXA-23-like) and biofilm-formation-related virulence genes (<i>abal</i>, <i>bfms</i>, <i>bap</i>, and <i>cusE</i>) were screened with PCR. Class 1 integron was screened with PCR, and common promoters and gene cassette arrays were determined with restriction pattern analysis combined with primer walking sequencing. Whole-genome sequencing was conducted, and data were analyzed for a <i>bla</i> _OXA-23-like-negative isolate. All 219 CRAB isolates were negative for <i>bla</i> _KPC, <i>bla</i> _VIM, <i>bla</i> _IMP, and <i>bla</i> _NDM, while <i>bla</i> _OXA-23-like was detected in 218 isolates. The detection rates for <i>abal</i>, <i>bfms</i>, <i>bap</i>, and <i>cusE</i> in 219 CRAB were 93.15%, 63.93%, 88.13%, and 77.63%, respectively. Class 1 integron was detected in 75 CRAB (34.25%) and in 3 CSAB. The single gene cassette array <i>aacA4-catB8-aadA1</i> with relatively strong PcH2 promoter was detected in class 1 integrons. The <i>bla</i> _OXA-23-like-negative CRAB isolate was revealed to be a new sequence type (Oxford 3272, Pasteur 2520) carrying <i>bla</i> _OXA-72, <i>bla</i> _OXA-259, and <i>bla</i> _ADC-26. In conclusion, <i>bla</i> _OXA-23-like was the main reason for CRAB's resistance to carbapenems. A new (Oxford 3272, Pasteur 2520) CRAB sequence type carrying the <i>bla</i> _OXA-72, <i>bla</i> _OXA-259, and <i>bla</i> _ADC-26 was reported.</p>","PeriodicalId":94173,"journal":{"name":"Polish journal of microbiology","volume":" ","pages":"189-197"},"PeriodicalIF":0.0,"publicationDate":"2024-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11192457/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141161683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Epidemiological Characteristics of Shiga Toxin-Producing <i>Escherichia coli</i> Responsible for Infections in the Polish Pediatric Population.","authors":"Dominika Seliga-Gąsior, Beata Sokól-Leszczyñska, Jolanta Krzysztoñ-Russjan, Diana Wierzbicka, Karolina Stępieñ-Hołubczat, Paulina Lewandowska, Ewa Frankiewicz, Andrzej Cacko, Beata Leszczyñska, Urszula Demkow, Edyta Podsiadły","doi":"10.33073/pjm-2024-016","DOIUrl":"10.33073/pjm-2024-016","url":null,"abstract":"<p><p>Shiga toxin-producing <i>Escherichia coli</i> (STEC) are zoonotic pathogens causing hemorrhagic colitis and hemolytic uremic syndrome (HUS) in children and the elderly. Stool samples were collected from 180 children hospitalized in five pediatric centers in Poland in 2018-2022. Direct <i>stx1</i>/<i>stx2</i> gene detection by PCR in feces and <i>E. coli</i> isolates was performed. Antibiotic susceptibility was tested according to EUCAST v.12. Randomly selected isolates were serotyped with O157 antiserum and genotyped by pulsed-field gel electrophoresis (PFGE). A total of 44 <i>E. coli</i> isolates were confirmed as STEC by PCR. Among them, 84.4% were positive for <i>stx2</i>, and equally 6,8% for only <i>stx1</i> and both <i>stx1</i> and <i>stx2</i> genes. The <i>stx1</i> gene was also found in one <i>Citrobacter freundii</i> isolate. <i>E. coli</i> serotype O157 was present in 97.6% of the isolates. STEC infections most often occurred between June-October with a peak in July and August (51%). The highest, 77.8% of STEC isolates were found in the 1-5 years old group. No extended-spectrum β-lactamases (ESBL) were found. Resistance only to amoxicillin/clavulanic acid (24.4%), piperacillin/tazobactam (3%), cefotaxime (6%), gentamicin (6%), ciprofloxacin (3%), azithromycin (3%), trimethoprim/sulfamethoxazole (24,2%) was detected. PFGE analysis showed 18 PFGE types with no clonal distribution. Eight isolates with A, B, and C PFGE types showed genetic relatedness in the type with no detection of transmission way of distribution. STEC strains pose a serious threat to human health, therefore demographic and epidemiological characteristics are crucial for their surveillance.</p>","PeriodicalId":94173,"journal":{"name":"Polish journal of microbiology","volume":" ","pages":"177-187"},"PeriodicalIF":0.0,"publicationDate":"2024-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11192175/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140900769","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of Azole Resistance Involving <i>cyp</i>51A and <i>cyp</i>51B Genes in Clinical <i>Aspergillus flavus</i> Isolates.","authors":"Dhoha Ghorbel, Imen Amouri, Nahed Khemekhem, Sourour Neji, Houaida Trabelsi, Moez Elloumi, Hayet Sellami, Fattouma Makni, Ali Ayadi, Ines Hadrich","doi":"10.33073/pjm-2024-001","DOIUrl":"10.33073/pjm-2024-001","url":null,"abstract":"<p><p>This study aimed to investigate azole resistance mechanisms in <i>Aspergillus flavus,</i> which involve <i>cyp</i>51A and <i>cyp</i>51B genes. Real-time Reverse Transcriptase qPCR method was applied to determine the overexpression of <i>cyp</i>51A and <i>cyp</i>51B genes for 34 <i>A. flavus</i> isolates. PCR sequencing of these two genes was used to detect the presence of gene mutations. Susceptibility test found sensitivity to voriconazole (VOR) in all strains. 14.7% and 8.8% of isolates were resistant to itraconazole (IT) and posaconazole (POS), respectively, with a cross-resistance in 5.8%. For the double resistant isolates (IT/POS), the expression of <i>cyp</i>51A was up to 17-fold higher. PCR sequencing showed the presence of 2 mutations in <i>cyp</i>51A: a synonymous point mutation (P61P) in eight isolates, which did not affect the structure of CYP51A protein, and another non synonymous mutation (G206L) for only the TN-33 strain (cross IT/POS resistance) causing an amino acid change in the protein sequence. However, we noted in <i>cyp</i>51B the presence of the only non-synonymous mutation (L177G) causing a change in amino acids in the protein sequence for the TN-31 strain, which exhibits IT/POS cross-resistance. A short single intron of 67 bp was identified in the <i>cyp</i>51A gene, whereas three short introns of 54, 53, and 160 bp were identified in the <i>cyp</i>51B gene. According to the models provided by PatchDock software, the presence of non-synonymous mutations did not affect the interaction of CYP51A and CYP51B proteins with antifungals. In our study, the overexpression of the <i>cyp</i>51A and <i>cyp</i>51B genes is the primary mechanism responsible for resistance in <i>A. flavus</i> collection. Nevertheless, other resistance mechanisms can be involved.</p>","PeriodicalId":94173,"journal":{"name":"Polish journal of microbiology","volume":" ","pages":"131-142"},"PeriodicalIF":0.0,"publicationDate":"2024-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11192525/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140854802","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}