Resistant Pathogens Research Articles

Are SNPs Linked to Somatic Cell Score Suitable Markers for the Susceptibility to Specific Mastitis Pathogens in Holstein Cows?

Mastitis in cattle is often caused by microorganism infections in the udder. The three most common pathogens are esculin-positive streptococci (SC+), coagulase-negative staphylococci (CNS), and Escherichia coli (E. coli). In a previous study, 10 SNPs were associated with somatic cell score and mastitis in diverse Holstein populations. We tested these SNPs for their effects on individual pathogen presence. Milk and pathogen samples of 3076 Holstein cows were collected from four farms. Samples were excluded if multiple pathogens were present at the same time. Records of the same pathogen within 14 days of each other were counted as one infection. This resulted in 1129 pathogen-positive samples. Cases and controls were in ratios of 20:80 for SC+, 8:92 for CNS, and 11:89 for E. coli. The lasso, backward, and forward methods were used to narrow down SNPs associated with pathogen presence. The suitability of the SNPs to separate the samples into cases or controls for each pathogen was indicated using ROC curves. The Cochran-Armitage (CAT) and the Jonckheere-Terpstra (JTT) tests evaluated the influence of the SNPs on pathogen presence. Finally, a generalised linear mixed model (GLMM) including fixed environmental effects and a random sire effect was fitted to the binary trait of pathogen presence to test for association. In total, six out of the 10 investigated SNPs showed associations with pathogen presence based on the forward method: Two SNPs each for SC+ (rs41588957, rs41257403) and CNS (rs109934030, rs109441194), and three for E. coli (rs109934030, rs41634110, rs41636878). The CAT and GTT tests linked four SNPs (rs41588957, rs41634110, rs109441194, rs41636878) to pathogen presence, two of which were confirmed with the GLMM (rs41634110, rs109441194), with effects on CNS and E. coli. The SNPs linked to CNS and those linked to E. coli explained 13.2% and 13.8% of the variance, compared to 19% and 18.4%, respectively, of the full model with all 10 SNPs. Half of the SNP genotypes previously linked to lower SCS also decreased the probability for pathogen presence and might therefore be targets not just for lower SCS but for a better pathogen resistance. Trial Registration: Not applicable, no new data were collected for this study.

Mechanistic Insight into the Role of Peptides Secreted from Bacillus clausii and Future Opportunities.

Bacillus clausii is a commercial spore probiotic known to treat multiple diseases. An increased interest in exploring the nutraceutical and probiotic properties of various microorganisms has made researchers explore more about these bacteria. The current trends in the healthcare industry are majorly focused on devising new therapies to avoid drug and pathogen resistance in patients. Antimicrobial peptides have been considered a source of antibiotics for a long time. Still, getting new therapies into the market is a big challenge. Members of the genus Bacillus have been reported to have a broad spectrum of antimicrobial peptides. One of the least explored species under this genus is Bacillus clausii, concerning peptide drug therapy. The applications of Bacillus clausii in treating or preventing gut dysbiosis and respiratory infections have been largely supported in the past two decades. Yet research is lacking in explaining the pathways at molecular levels in targeting pathogens. In this mini-review, we are going to summarise the research that has been reported so far about peptide extraction from Bacillus clausii, their mode of action and advantages to mankind, and the challenges lying in the isolation of peptides.

Efflux-mediated Multidrug Resistance in Critical Gram-negative Bacteria and Natural Efflux Pump Inhibitors.

Multidrug Resistance mechanisms in microorganisms confer the slackness of the existing drugs, leading to added difficulty in treating infections. As a consequence, efficient novel drugs and innovative therapies to treat MDR infections are necessarily required. One of the primary contributors to the emergence of multidrug resistance in gram-negative bacteria has been identified as the efflux pumps. These transporter efflux pumps reduce the intracellular concentration of antibiotics and aid bacterial survival in suboptimal low antibiotic concentration environments that may cause treatment failure. The reversal of this resistance via inhibition of the efflux mechanism is a promising method for increasing the effectiveness of antibiotics against multidrug-resistant pathogens. Such EPI, in combination with antibiotics, can make it easier to reintroduce traditional antibiotics into clinical practice. This review mostly examines efflux-mediated multidrug resistance in critical gram-negative bacterial pathogens and EPI of plant origin that have been reported over previous decades.

Phage therapy: A primer for orthopaedic trauma surgeons.

Phage therapy (PT) continues to attract interest in the fight against fracture-related infection (FRI), particularly for recurring infections that have not been resolved using conventional therapeutic approaches. The journey PT has taken from early clinical application in the pre-antibiotic era to its recent reintroduction to western clinical practice has been accelerated by the increased prevalence of multi-drug resistant (MDR) pathogens in the clinic. This review will present PT's potential as a precise, adaptable, and effective treatment modality, with a focus on patient and phage selection, as well as the various administration protocols currently applied to patients. The challenges for PT, for example the most optimal application technique and dosing, are also discussed and underscore the importance of personalized approaches and the urgent need for more robust clinical evidence. Future perspectives, including phage engineering and innovative delivery systems will be discussed, as they may broaden the applicability of PT to a point where it may become a standard rather than an option of last resort for orthopedic infection management.

Increased antimicrobial resistance of acid-adapted pathogenic Escherichia coli, and transcriptomic analysis of polymyxin-resistant strain

This study investigated the acid adaptation and antimicrobial resistance of seven pathogenic Escherichia coli strains and one commensal strain under nutrient-rich acidic conditions. After acid adaptation, three pathogenic E. coli survived during 100 h incubation in tryptic soy broth at pH 3.25. Acid-adapted (AA) strains showed increased resistance to antimicrobials including ampicillin, ciprofloxacin and especially polymyxins (colistin and polymyxin B), the last resort antimicrobial for multidrug-resistant Gram-negative bacteria. Enterotoxigenic E. coli strain (NCCP 13717) showed significantly increased resistance to acids and polymyxins. Transcriptome analysis of the AA NCCP 13717 revealed upregulation of genes related to the acid fitness island and the arn operon, which reduces lipopolysaccharide binding affinity at the polymyxin site of action. Genes such as eptA, tolC, and ompCF were also upregulated to alter the structure of the cell membrane, reducing the outer membrane permeability compared to the control, which is likely to be another mechanism for polymyxin resistance. This study highlights the emergence of antimicrobial resistance in AA pathogenic E. coli strains, particularly polymyxin resistance, and the mechanisms behind the increased antimicrobial resistance, providing important insights for the development of risk management strategies to effectively control the antimicrobial resistant foodborne pathogens.

Limonene encapsulated alginate/collagen as antibiofilm drug against Acinetobacter baumannii

This work examined the antibacterial and antibiofilm properties of alginate/collagen nanoparticles containing limonene. The multi-drug resistant (MDR) strains were screened, and the morphological features of the produced nanoparticles were determined utilizing SEM, DLS, and FTIR. Additionally, the encapsulation effectiveness, stability, and drug release were assessed. The levels of OmpA and Bap biofilm genes were assessed using qRT-PCR. At the same time, the antibacterial and cytotoxic activities of the nanoparticles were evaluated using well diffusion and MTT techniques, respectively. LAC nanoparticles measuring 300 ± 9.6 nm in size, 83.64 ± 0.19% encapsulation efficiency, and 60-day stability at 4 °C were synthesized. The biological investigation demonstrated that LAC nanoparticles had potent antibacterial capabilities. This was shown by their ability to significantly decrease the transcription of OmpA and Bap biofilm genes at a statistically significant level of p ≤ 0.05. The nanoparticles exhibited reduced antibiotic resistance compared to free limonene and alginate/collagen. Compared to limonene, LAC nanoparticles exhibited negligible cytotoxicity against HEK-293 at doses ranging from 1.56 to 100 µg/mL (p ≤ 0.01). The findings underscore the potential of LAC nanoparticles as a breakthrough in the fight against highly resistant pathogens. The potent antibacterial effects of LAC nanoparticles versus Acinetobacter baumannii (A. baumannii) MDR strains, considered highly resistant pathogens of significant concern, could inspire new strategies in antibacterial research.

Flexible Development Programs for Antibacterial Drugs to Address Unmet Medical Needs.

The US Food and Drug Administration recognizes the unmet medical need for antibacterial drugs to treat serious bacterial diseases caused by resistant pathogens for which effective therapies are limited or lacking. The agency also recognizes that designing and conducting clinical trials to assess the safety and efficacy of drugs to treat resistant infections is challenging, especially for drugs only active against a single or a few bacterial species, and that a more flexible development program might be appropriate. In this article, we discuss several regulatory considerations for flexible development programs for antibacterial drugs intended to meet an unmet medical need. As an example, we use the recent approval of sulbactam for injection and durlobactam for injection (XACDURO) for the treatment of hospital-acquired bacterial pneumonia and ventilator-associated bacterial pneumonia caused by susceptible isolates of Acinetobacter baumannii-calcoaceticus complex.

Guanethidine Enhances the Antibacterial Activity of Rifampicin Against Multidrug-Resistant Bacteria

The escalating global threat of antibiotic resistance necessitates innovative strategies, such as the combination of antibiotics with adjuvants. Monotherapy with rifampicin is more likely to induce resistance in pathogens compared to other antibiotics. Herein, we found that the antihypertensive drug guanethidine enhanced the activity of rifampicin against certain clinically resistant Gram-negative bacteria, resulting in a reduction of up to 128-fold in the minimum inhibitory concentration. In infected animal models, this combination has achieved treatment benefits, including increased survival and decreased bacterial burden. The antimicrobial mechanism of guanethidine in synergy with rifampicin involves the disruption of the outer membrane of Gram-negative bacteria, leading to dissipation of the proton motive force. This results in an increase in reactive oxygen species and a reduction in ATP synthesis, severely disturbing energy metabolism and ultimately increasing bacterial mortality. In summary, guanethidine has the potential to become a novel adjuvant for rifampicin, offering a new option for the treatment of clinical Gram-negative bacterial infections.

Antibacterial and Antifungal Activity of Metabolites from Basidiomycetes: A Review

Background/Objectives: The search for new antimicrobial molecules is important to expand the range of available drugs, as well as to overcome the drug resistance of pathogens. One of the promising sources of antibacterial and antifungal metabolites is basidial fungi, which have wide biosynthetic capabilities. Methods: The review summarized the results of studying the antimicrobial activity of extracts and metabolites from basidiomycetes published from 2018–2023. Results: In all studies, testing for antibacterial and antifungal activity was carried out in in vitro experiments. To obtain the extracts, mainly the fruiting bodies of basidiomycetes, as well as their mycelia and culture liquid were used. Antimicrobial activity was found in aqueous, methanol, and ethanol extracts. Antimicrobial metabolites of basidiomycetes were isolated mainly from the submerged culture of basidiomycetes. Metabolites active against Gram-positive and Gram-negative bacteria and mycelial and yeast-like fungi were identified. Conclusions: Basidiomycete extracts and metabolites have shown activity against collectible strains of bacteria and fungi and multi-resistant and clinical strains of pathogenic bacteria. The minimum inhibitory concentration (MIC) values of the most active metabolites ranged from 1 to 16.7 µg/mL.

Spectrum and Antifungal Drug Resistance among Fungal Pathogens Isolated from Prison Inmates in Nairobi, Kenya

Background The emergence of antifungal resistance in fungal pathogens highlights the need for local epidemiological data to guide empirical therapy in clinical settings. Fungal research and anti-fungal drug resistance studies are limited in developing countries; hence, there is a need for burden estimation in low- and middle-income countries. This study aimed to determine the spectrum of fungal pathogens and the anti-fungal resistance profile of fungal pathogens isolated from the respiratory and urinary tracts of prison inmates in Nairobi, Kenya. Methods A cross-sectional study was conducted in which sputum and urine samples were obtained from inmates presenting with symptoms of respiratory and urogenital infections at a prison outpatient clinic. One hundred and sixty-two samples were collected and subjected to fungal investigation using standard protocols. Susceptibility to fluconazole, itraconazole, and voriconazole was assessed using standard broth microdilution. Clinical and sociodemographic data were obtained using a structured questionnaire. Results From the 162, 94 samples were positive for fungal pathogens, with an overall prevalence of 58%. Seventeen (18%) of the isolated fungi were Aspergillus fumigatus, Aspergillus flavus and Histoplasma. There was a statistically significant difference between fungal pathogens isolated from the respiratory and urogenital tracts in both sexes (p<0.05). Antifungal susceptibility testing against itraconazole showed 2 of Aspergillus flavus and Aspergillus fumigatus were resistant. Conclusion Mycological agents are significant causes of respiratory and UTI infections among prison inmates, which could be attributed to prison conditions and misdiagnosis as bacterial infections. This highlights the need for specific control measures to reduce exposure to fungal infections in prisons and in the general population.

Intrinsic Natural Resistance of Various Plant Pathogens to Ipflufenoquin, a New DHODH (Dihydroorotate Dehydrogenase)-inhibiting Fungicide, in Relation to Unaltered Amino Acid Sequence of the Target Site.

In recent years, increasingly stringent pesticide regulations have made the development of new chemistries challenging. Under these regulations, the new fungicide ipflufenoquin (FRAC Code 52) was first released in Japan. Its mode of action is new; it inhibits dihydroorotate dehydrogenase (DHODH), a key enzyme in the biosynthesis of pyrimidine-based nucleotides. However, because it is a single-site inhibitor, the risk of resistance developing in pathogens must be carefully considered. The risk for dual use of DHODH inhibitors in agriculture and medicine has also become a great concern because a new antifungal olorofim is under development against human pathogens now and cross-resistance has recently been reported between ipflufenoquin and olorofim in Aspergillus fumigatus. In this study, the sensitivity to ipflufenoquin was examined in culture and in plants using "baseline" isolates, which had never been exposed to DHODH inhibitors. Isolates of Alternaria alternata, Botrytis cinerea, B. elliptica, Colletotrichum fioriniae, C. fructicola, C. nymphaeae, C. orbiculare, C. siamense, C. tropicale, C. truncatum, and Sclerotinia sclerotiorum were highly sensitive to ipflufenoquin in culture, but isolates of Coniella vitis, Corynespora cassiicola, Pseudocercospora fuligena, and Rhizoctonia solani were inherently resistant. Ipflufenoquin had low efficacy against C. cassiicola and C. vitis after inoculation of cucumber and grapevine leaves, respectively. To understand the mechanism of natural resistance, we analyzed the partial sequence of pyrE genes, which encode the DHODH enzyme, but did not find any differences in the deduced amino acids that were thought to be associated with resistance. Thus, mechanisms other than target-site mutations might be involved in the intrinsic resistance.

Unleashing the synergistic effect of promising fungicides: a breakthrough solution for combating powdery mildew in pea plants

Pea powdery mildew, caused by Erysiphe pisi, is a major limitation to global pea production. The emergence of fungicide-resistant pathogen populations due to frequent and injudicious pesticide application highlights the importance of exploring the synergistic properties of fungicide combinations. This study investigated the efficacy of difenoconazole, thiophanate-methyl, and sulfur, both individually and in mixtures, against powdery mildew and assessed the interaction types between these fungicides. The results demonstrated that the combination of difenoconazole, thiophanate-methyl, and sulfur was the most effective in reducing, reducing disease severity to 6.10% and minimizing conidial production on foliage. Additionally, this fungicide combination reduced conidial germination by 89.26% in vitro and by 87.50% in a detached leaf assay compared to the control. The treatment also positively impacted leaf chlorophyll content (55.18), green pod yield (22.21 tons ha−1), seed yield (12.29 tons ha−1), and other yield-related parameters. Although statistically significant, this ternary fungicide combination was closely followed by the binary combination of thiophanate-methyl and sulfur, which was the only combination exhibiting synergism in both laboratory and field trials with a synergy factor (SF) > 1. In conclusion, this approach offers improved disease control as part of integrated disease management (IDM) while minimizing the risk of resistant pathogen strains.

Use of stable isotope combined with intact cell lipidomic by routine MALDI mass spectrometry analysis for rapid drug susceptibility assay in mycobacteria.

Rapid, accurate, and easy-to-perform diagnostic assays are required to address the current need for the diagnosis of resistant pathogens. That is particularly the case for mycobacteria, such as the human pathogen Mycobacterium tuberculosis, which requires up to 2weeks for the determination of the drug susceptibility profile using the conventional broth microdilution method. To address this challenge, we investigated the incorporation of deuterium, the stable isotope of hydrogen, into lipids as a read out of the drug susceptibility profile. Deuterium is incorporated into newly synthesized proteins or lipids in place of hydrogen as bacterial cells grow, increasing the mass of the macromolecules, which can then be observed via matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS). As proof-of-concept, we used the non-pathogenic Mycobacterium smegmatis mc2155 strain, which is susceptible to the aminoglycoside antibiotic kanamycin, and M.smegmatis mc2155 containing the empty vector pVV16, which is kanamycin-resistant. Bacteria were incubated in a culture medium containing 50% of deuterium oxide (D2O) and either 1 or 2 times the minimal inhibitory concentration (MIC50) of kanamycin. Lipids were then analyzed using the MBT lipid Xtract matrix combined with routine MALDI mass spectrometry in the positive ion mode to evaluate the changes in the lipid profile. Using this approach, we were able to distinguish susceptible from resistant bacteria in less than 5h, a process that would take 72 h using the conventional broth microdilution method. We therefore propose a solution for the rapid determination of drug susceptibility profiles using a phenotypic assay combining D2O stable isotope labelling and lipid analysis by routine MALDI mass spectrometry.

Plant cell wall structure and dynamics in plant-pathogen interactions and pathogen defence.

Plant cell walls delimit plant cells from their environment and provide mechanical stability to withstand internal turgor pressure as well as external influences. Environmental factors can be beneficial or harmful for the plants and vary substantially depending on prevailing combinations of climate conditions and stress exposure. Consequently, the physicochemical properties of plant cell walls need to be adaptive, and their functional integrity needs to be monitored by the plant. One major threat to plants is posed by phytopathogens, which employ a diversity of infection strategies and lifestyles to colonise host tissues. During these interactions, the plant cell wall represents a barrier that impedes the colonisation of host tissues and pathogen spread. In a tussle over maintenance and breakdown, plant cell walls can be rapidly and efficiently remodelled by enzymatic activities of plant and pathogen origin, heavily influencing the outcome of plant-pathogen interactions. We review the role of locally and systemically induced cell wall remodelling and the importance of tissue-dependent cell wall properties for the interaction with pathogens. Furthermore, we discuss the importance of cell wall-dependent signalling for defence response induction and the influence of abiotic factors on cell wall integrity and cell wall-associated pathogen resistance mechanisms.

Genome-Wide Identification and Characterization Thaumatin-like Protein (TLP) Genes in Wild Olive (Olea europaea var. sylvestris)

The wild olive tree (Olea europaea var. sylvestris) is the ancestor of all olive varieties, displaying remarkable adaptability to diverse climatic conditions and soil types. This iconic tree of the Mediterranean Basin stands out for its ability to withstand environmental stresses, such as water scarcity and temperature variations, playing a crucial role in the ecology, economy, and culture of the region. In this study, 42 TLP genes were characterized in the wild olive tree, distributed across 14 chromosomes and nine scaffolds. In silico analysis revealed the presence of domains associated with antifungal activity in some sequences, indicating their potential role in pathogen resistance. The structural diversity of OeTLP genes was explored through multiple alignments, conserved motifs and phenetic analysis. Correlation was observed between phenetic diversity, genetic structure, and motif patterns, suggesting different functions among OeTLP groups. Additionally, the distribution of exons and introns in the pheneticc tree provided further insights into the evolution of these genes. Comparative modeling of OeTLPs unveiled three-dimensional models with good structural quality and distinctive surface charge characteristics. This study provides a comprehensive understanding of the physicochemical, structural, and phenetic features of TLP genes in Wild Olive, contributing to knowledge about this species' response to environmental stresses and pathogens.

One Health in Europe: from concept to practice

Abstract The One Health concept is a comprehensive approach that highlights the interconnectedness of human, animal, and environmental health. Understanding these interrelationships is essential for effectively managing and mitigating emerging health threats. This approach emphasizes that health issues arise from a complex web of interactions involving humans, animals, and ecosystems. Emerging health threats, such as zoonotic diseases (e.g., mpox, Ebola, avian influenza), antibiotic resistance, and environmental degradation, pose significant risks to global health. Zoonotic diseases, which are transmitted between animals and humans, highlight the direct links between animal and human health. The increase in antibiotic resistance, driven by overuse in both human medicine and livestock farming, leads to the rise of resistant pathogens. Environmental issues like climate change, deforestation, and pollution further exacerbate these threats by altering habitats, disrupting ecosystems, and affecting disease vectors. Addressing these interconnected challenges requires a unified approach that integrates human, animal, and environmental considerations. For example, climate change can shift the distribution of disease vectors like mosquitoes, leading to the spread of diseases such as malaria and dengue fever. Likewise, deforestation can heighten the risk of zoonotic spillover by bringing humans into closer contact with wildlife. 1. To tackle these complex challenges, several measures are crucial: • Integrated surveillance systems Developing systems that monitor human, animal, and environmental health data collectively can improve early detection of outbreaks. Sharing information across sectors is a prerequisite for effective identification of emerging threats. • Strengthening veterinary and public health collaboration Joint research, surveillance, and outbreak management efforts can lead to a more coordinated approach to health emergencies. • Promoting One Health education and training Educating professionals in various fields fosters a collaborative approach to health issues. Training programmes can build a shared understanding of health interconnections. • Implementing sustainable environmental practices Adopting sustainable practices to address environmental degradation helps reduce risks associated with habitat destruction and pollution. • International collaboration and agreements facilitate resource sharing, information exchange, and best practices. 2. To enhance public health strategies within the One Health framework: • Enhance interdisciplinary research Promote research on the intersections of human, animal, and environmental health to understand how changes in one area affect others and to develop more effective interventions. • Foster community engagement Engage communities to improve the adoption of preventive measures and build resilience against health threats through public awareness and community-based programs. Leverage technology and innovation Innovations can offer valuable insights such as data analytics, remote sensing, and genomic surveillance. In our upcoming plenary session, experts from veterinary and public health sciences will present practical examples on One Health collaboration in Europe and discuss how to address challenges in implementing the approach. Moderator Ricardo Mexia Chair of the 17th EPH Conference 2024, President EUPHA Infectious diseases control section Keynote speaker Lorena Boix Deputy Director-General, Directorate General for Health and Food Safety (DG SANTE), European Commission Speakers/Panellists Stef Bronzwaer Cross-Agency One Health Task Force, European Food Safety Authority (EFSA) Barbara Häsler Royal Veterinary College, UK Susana Guedes Pombo Chief Veterinary Officer, Portugal, President World Organization for Animal Health (WOAH) Eva Zažímalová Member of European Commission's Group of Chief Scientific Advisors, Professor of Plant Anatomy and Physiology, Charles University, Czech Republic

Efflux Pump Inhibitors as a Broad-Spectrum Strategy to Combat Multidrug Resistance Acenitobacter Baumanii

The World Health Organization (WHO) identifies A. baumannii as one of the most resistant pathogens. Over the past few years, there has been a significant rise in its resistance to a wide array of antibiotics. Multidrug resistance is attributed to several mechanisms, with efflux pumps being the most notable. Recently, the development of new treatment strategies to tackle A. baumannii infections has shown great promise. This review focuses on the various families of efflux pumps in A. baumannii and explores innovative therapeutic options that have emerged over the past four years. Specifically, we emphasize synthetic and natural efflux pump inhibitors (EPIs), nanoparticles, bacteriophage therapy, and antimicrobial peptides (AMPs) as part of these novel strategies.

Molecular characterization and antimicrobial resistance of bacterial pathogens in neonatal sepsis: A cross-sectional study at a Lagos tertiary hospital

Molecular characterization and antimicrobial resistance of bacterial pathogens in neonatal sepsis: A cross-sectional study at a Lagos tertiary hospital

Propiconazole resistance phenotypes in Geotrichum candidum from South Carolina peaches are linked to point mutations in GcCYP51B gene.

Geotrichum candidum Link (1809) is a yeast-like fungus that causes sour rot of peach (Prunus persica). Outbreaks of the disease have occurred since 2021 in peach fruit kept in cold storage despite post-harvest treatments with propiconazole at a commercial farm in South Carolina (SC). A total of 58 isolates, 40 from symptomatic fruit from cold storage in Saluda County (SC packing house isolates), 11 from three SC orchards in Saluda County, Spartanburg County, and Pickens County (SC non-packing house isolates), and 7 California (CA) isolates (at least 3 from packing houses) were evaluated for propiconazole sensitivity. Mycelial growth assays revealed that 6 of 7 CA isolates had the lowest EC50 values and were considered sensitive (S) to propiconazole with an average EC50 value of 0.02 µg/ml and minimum inhibitory concentration (MIC) values >1 to < 3 µg/ml. Isolate 02J018 from CA and all SC non packing house isolates were considered reduced-sensitive (RS) to propiconazole with an average EC50 value of 0.33 µg/ml and MIC values >10 to <30 µg/ml. SC packing house isolates were considered resistant (R) to propiconazole and had an average EC50 value of 3.55 µg/ml and MIC values >300 µg/ml. Two CYP51 genes, GcCYP51A and GcCYP51B, encoding two demethylase inhibitor (DMI) target enzyme 14α-demethylases were identified, sequenced, and characterized. Two GcCYP51A and three GcCYP51B variants were found. While both GcCYP51A variants were linked to S isolates, the GcCYP51B2 variant possessing the mutation Y143F was found in RS, and the GcCYP51B3 variant possessing Y143F, E126K, and G460S mutations was identified in R isolates. The Y143F and G460S mutations had been associated with DMI fungicide resistance in other plant pathogens. No increased constitutive expression of GcCYP51A or GcCYP51B was observed in RS or R isolates. Detached fruit assays revealed that label rates of propiconazole controlled sour rot caused by S and RS but not R isolates. Our results suggest that sour rot outbreaks in a SC packing house were linked to target gene-induced propiconazole resistance in G. candidum.

Decoding Multidrug Resistance: Genetic Architecture and Codon Usage Patterns in ESKAPE Pathogens

Introduction: The escalating challenge of multidrug resistance among ESKAPE pathogens has become a prominent concern for global healthcare providers, leading to amplified morbidity and mortality rates. Method: Therefore, we conducted this study to elucidate the genetic architecture of ESKAPE constituents with the intent of ameliorating pathogenicity and facilitating drug development efforts. A comprehensive array of computational tools and statistical methodologies were employed to scrutinize the genomes of ESKAPE pathogens, revealing that translational selection profoundly influences the codon usage bias within this pathogenic cohort. Notably, leucine emerged as the predominantly amino acid, except in the case of Acinetobacter baumannii, where arginine exhibited preeminence. There was a universal preference for at least one histidine codon across all ESKAPE pathogens. GpC emerged as the most prominently overrepresented dinucleotide at the codon pair junction in all ESKAPE pathogens. Result: Furthermore, a comparison of gyrB gene sequences and phylogenic tree construction showed a distinct evolutionary relationship between AT-rich and GC-rich ESKAPE pathogens. Additionally, identification, characterization, and phylogenetic analysis of multiple antibiotic resistance genes revealed distinct evolutionary relationships. Conclusion: It was discerned that despite substantial variability amongst antibioticresistance genes, leucine emerged as the predominant amino acid. conclusion: Ultimately, we can say that codon and amino acid usage bias in ESKAPE pathogens and their ARGs genes has contributed the evolution of antibiotic resistance nature if the pathogens. Therefore, our study underscores the importance of continued surveillance and research efforts to address the growing threat of antibiotic resistance in ESKAPE pathogens .