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Kuo, S.-C.

Publications and source records attributed to Kuo, S.-C..

3 recordsLinked to original sources

Evaluation of Oxford Nanopore Sequencing for Antimicrobial Resistance Surveillance in Salmonella: Comparison with Phenotypic Antimicrobial Susceptibility in a Large-Scale Study

Salmonella is a major zoonotic foodborne pathogen, and antimicrobial resistance (AMR) in Salmonella presents a significant public health challenge. Whole-genome sequencing (WGS) offers a more rapid and comprehensive method for AMR characterization compared to conventional antimicrobial susceptibility testing (AST), supporting antimicrobial therapy and surveillance efforts. In this study, Oxford Nanopore Technology (ONT)-based WGS was performed on 1,490 Salmonella isolates collected through nationwide surveillance in Taiwan in 2025. Genotypic resistance inferred from WGS data was compared with phenotypic AST results to assess the performance of ONT-WGS. Overall, WGS-inferred resistance showed high concordance with phenotypic resistance for most antimicrobials. However, major genotype- phenotype discordance was observed, attributed to four categories: (i) breakpoint-dependent classification, (ii) reduced or absent phenotypic expression of resistance genes, (iii) MIC modulation by ramAp, and (iv) absence of known AMR determinants. Notable discrepancies included tigecycline resistance without known genetic determinants, nalidixic acid resistance linked to ramAp-mediated MIC elevation, and a high prevalence of colistin resistance (35.4%) in S. Enteritidis without identifiable AMR determinants. Additionally, a significant proportion of ESBL- and AmpC-producing isolates were classified as susceptible or intermediate to cefotaxime and ceftazidime under CLSI criteria, highlighting the potential for misclassification and treatment failure. These findings demonstrate that ONT-WGS enables accurate, comprehensive AMR characterization, offering direct identification of AMR determinants and minimizing misclassification due to breakpoint-based AST interpretations. When interpreted appropriately, WGS can support better antimicrobial selection and serve as a valuable alternative to conventional susceptibility testing.

microbiology↗

Evolutionary conserved sap peptides derived from xylem-specific peptide precursors in woody angiosperms

Peptides act as long-distance mobile signals, transported through vascular sap to coordinate complex developmental processes. Since the tissue-specificity of peptide precursor gene expression is critical in determining peptide signaling function, we integrated vascular sap peptidomes with tissue-level transcriptomes to investigate the roles of sap peptides in two economically important woody plants, Populus trichocarpa and Eucalyptus grandis. Xylem exhibited the highest ratio of tissue-specific sap peptide precursor genes. Most of the sap peptides derived from xylem-specific precursor genes of P. trichocarpa and E. grandis were highly conserved throughout woody species selected from different clades in angiosperms, including magnoliids, rosids and asterids in eudicots. To further explore the conservation of these peptides, we examined the sap peptidome of Cinnamomum kanehirae (camphor tree), from the ancient clade with three xylem cell types. Approximately 90% of the peptides from xylem-specific precursors that were conserved between P. trichocarpa and E. grandis, were also conserved in the vascular sap of C. kanehirae, demonstrating a remarkably high conservation of these peptides across woody angiosperms. Most of the sap peptides conserved in these three woody species are also highly conserved across land plants, suggesting that these peptides may contribute to plant terrestrialization. Within the sap peptides from xylem- specific precursor genes, a total of 10 peptides were identical across all three woody plants. This substantial enrichment of xylem-specific precursor-derived peptides, along with their high conservation, suggests that these long-distance mobile peptides play a crucial role in secondary xylem development. One sentence summaryIntegration of sap peptidomic and tissue-level transcriptomic data revealed highly conserved long-distance mobile peptides derived from xylem- specific precursors across woody angiosperms.

evolutionary biology↗

Single-cell transcriptomics unveils xylem cell development and evolution

As the most abundant tissue on Earth1, xylem is responsible for lateral growth in plants. Typical xylem has a radial system composed of ray parenchyma cells and an axial system of fusiform cells2. In most angiosperms, fusiform cells are a combination of vessel elements for water transportation and libriform fibers for mechanical support, while both functions are performed together by tracheids in other vascular plants2. However, little is known about the developmental programs and evolutionary relationships of these xylem cell types. Through both single-cell and laser-capture microdissection transcriptomic profiling, here we demonstrate the developmental lineages of ray and fusiform cells in stem-differentiating xylem across four divergent woody angiosperms. Cross-species analyses of single-cell trajectories reveal highly conserved ray, yet variable fusiform, lineages across angiosperms. Core eudicots Populus trichocarpa and Eucalyptus grandis share nearly identical fusiform lineages. The tracheids in the basal eudicot Trochodendron aralioides, an evolutionarily reversed character3, 4, exhibit strong transcriptomic similarity to vessel elements but not libriform fibers, suggesting that water transportation, instead of mechanical support, is the major feature. We also found that the more basal angiosperm Liriodendron chinense has a fusiform lineage distinct from that in core eudicots. This evo-developmental framework provides a comprehensive understanding of the formation of xylem cell lineages across multiple plant species spanning over a hundred million years of evolutionary history5.

plant biology↗