5.8 Summary

Step Choice made Rationale
ORA package mulea Empirical FDR correction; accounts for gene set interdependence
GSEA package fgsea Gold standard for preranked GSEA; proper NES and permutation p-values
Gene sets KEGG pathways Matches Dedios 2025; biologically interpretable for bacteria
GMT source KEGGREST API + local RDS cache No pre-built KEGG GMT for E. coli; built from API and cached
ID conversion Locus tag to gene symbol via KEGGREST nf-core uses locus tags when GTF lacks gene_name; KEGG GMT uses symbols
ORA background All DESeq2-tested genes Correct statistical background — not the full genome
GSEA rank metric sign(LFC) x -log10(pvalue) Encodes direction and significance; robust to lowly expressed gene noise
ORA FDR Empirical FDR (eFDR) Accounts for gene set interdependence
GSEA FDR Benjamini-Hochberg (fgsea default) Standard for preranked GSEA
Significance threshold 0.05 Standard; consistent with DE analysis

Enrichment results are saved and ready for biological interpretation and reporting.


sessionInfo()
## R version 4.4.1 (2024-06-14)
## Platform: aarch64-apple-darwin20
## Running under: macOS Sonoma 14.3
## 
## Matrix products: default
## BLAS:   /Library/Frameworks/R.framework/Versions/4.4-arm64/Resources/lib/libRblas.0.dylib 
## LAPACK: /Library/Frameworks/R.framework/Versions/4.4-arm64/Resources/lib/libRlapack.dylib;  LAPACK version 3.12.0
## 
## locale:
## [1] en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8
## 
## time zone: Europe/Copenhagen
## tzcode source: internal
## 
## attached base packages:
## [1] stats4    stats     graphics  grDevices utils     datasets  methods  
## [8] base     
## 
## other attached packages:
##  [1] KEGGREST_1.46.0             fgsea_1.32.4               
##  [3] mulea_1.1.1                 plotly_4.12.0              
##  [5] DT_0.34.0                   kableExtra_1.4.0           
##  [7] knitr_1.51                  factoextra_2.0.0           
##  [9] pheatmap_1.0.13             RColorBrewer_1.1-3         
## [11] ggpubr_0.6.3                DESeq2_1.46.0              
## [13] SummarizedExperiment_1.36.0 Biobase_2.66.0             
## [15] MatrixGenerics_1.18.1       matrixStats_1.5.0          
## [17] GenomicRanges_1.58.0        GenomeInfoDb_1.42.3        
## [19] IRanges_2.40.1              S4Vectors_0.44.0           
## [21] BiocGenerics_0.52.0         reshape2_1.4.5             
## [23] lubridate_1.9.5             forcats_1.0.1              
## [25] stringr_1.6.0               dplyr_1.2.1                
## [27] purrr_1.2.2                 readr_2.2.0                
## [29] tidyr_1.3.2                 tibble_3.3.1               
## [31] ggplot2_4.0.3               tidyverse_2.0.0            
## 
## loaded via a namespace (and not attached):
##  [1] rlang_1.2.0             magrittr_2.0.5          otel_0.2.0             
##  [4] compiler_4.4.1          png_0.1-9               systemfonts_1.3.2      
##  [7] vctrs_0.7.3             pkgconfig_2.0.3         crayon_1.5.3           
## [10] fastmap_1.2.0           backports_1.5.1         XVector_0.46.0         
## [13] labeling_0.4.3          rmarkdown_2.31          tzdb_0.5.0             
## [16] UCSC.utils_1.2.0        xfun_0.57               zlibbioc_1.52.0        
## [19] cachem_1.1.0            jsonlite_2.0.0          DelayedArray_0.32.0    
## [22] BiocParallel_1.40.2     broom_1.0.12            parallel_4.4.1         
## [25] R6_2.6.1                bslib_0.10.0            stringi_1.8.7          
## [28] car_3.1-5               numDeriv_2016.8-1.1     jquerylib_0.1.4        
## [31] Rcpp_1.1.1-1.1          bookdown_0.46           Matrix_1.7-5           
## [34] timechange_0.4.0        tidyselect_1.2.1        rstudioapi_0.18.0      
## [37] abind_1.4-8             yaml_2.3.12             codetools_0.2-20       
## [40] lattice_0.22-9          plyr_1.8.9              withr_3.0.2            
## [43] S7_0.2.2                coda_0.19-4.1           evaluate_1.0.5         
## [46] xml2_1.5.2              Biostrings_2.74.1       pillar_1.11.1          
## [49] carData_3.0-6           generics_0.1.4          emdbook_1.3.14         
## [52] hms_1.1.4               scales_1.4.0            glue_1.8.1             
## [55] lazyeval_0.2.3          tools_4.4.1             apeglm_1.28.0          
## [58] data.table_1.18.2.1     locfit_1.5-9.12         ggsignif_0.6.4         
## [61] mvtnorm_1.3-6           fastmatch_1.1-8         cowplot_1.2.0          
## [64] grid_4.4.1              bbmle_1.0.25.1          crosstalk_1.2.2        
## [67] bdsmatrix_1.3-7         colorspace_2.1-2        GenomeInfoDbData_1.2.13
## [70] Formula_1.2-5           cli_3.6.6               textshaping_1.0.5      
## [73] S4Arrays_1.6.0          viridisLite_0.4.3       svglite_2.2.2          
## [76] gtable_0.3.6            rstatix_0.7.3           sass_0.4.10            
## [79] digest_0.6.39           SparseArray_1.6.2       ggrepel_0.9.8          
## [82] htmlwidgets_1.6.4       farver_2.1.2            htmltools_0.5.9        
## [85] lifecycle_1.0.5         httr_1.4.8              MASS_7.3-65