MetTailor

MetTailor performs alignment and normalization of untargeted mass spectrometry (MS) metabolomics data to improve the reliability of quantitative analysis in large-scale studies.

Key Features:

• Dynamic Block Summarization (DBS): Corrects misalignments from peak alignment algorithms by realigning peaks across samples to mitigate missing data.
• Isotopic intensity ratio quality metric: Uses cross-sample consistency in isotopic intensity ratios to verify the correctness of re-alignments.
• Flexible Intensity Normalization: Adjusts normalization factors to account for temporal variations in the total ion chromatogram (TIC) along chromatographic retention time (RT), removing local TIC variations while preserving sensitivity for detecting differentially expressed metabolites.
• Preprocessing steps for untargeted metabolomics: Implements preprocessing procedures aimed at enhancing the reliability of quantitative analysis in untargeted metabolomics datasets.

Scientific Applications:

• Large-scale untargeted metabolomics without MS/MS: Provides alignment and normalization tailored for studies where tandem mass spectrometry (MS/MS) is not typically used for compound identification.
• Peak realignment and missing-data correction: Identifies and corrects misaligned peaks to improve cross-sample consistency and downstream differential-metabolite detection.
• Method evaluation: Demonstrated sensitivity for identifying and correcting misaligned peaks using a curated metabolomics dataset.

Methodology:

Implements Dynamic Block Summarization for peak re-alignment, a flexible intensity normalization that adjusts normalizing factors to remove local TIC variations across chromatographic retention time (RT), and uses cross-sample isotopic intensity ratio consistency as a quality metric; evaluated on a curated metabolomics dataset.