Input file: Config file

Config file includes three types of information: (i) what data (omics & metadata), (ii) what analyses and (iii) what public resources to be used. Graph modeling is automatically performed based on the analysis types and the public resources defined in the configuration file.

Configuration file is a yaml file with four sections: (i) input, (ii) metadata, (iii) pipeline and (iv) public.



Section: input

Example

input:
  transcriptome:
    path: transcriptome.TPM.txt
    format: tsv
    rownames: Symbol
    unit: TPM
  microbiome:
    path: microbiome.Ratio.txt
    format: tsv
    rownames: Genus
    unit: Ratio
  metabolome:
    path: metabolome.PPM.txt
    format: tsv
    rownames: Name
    unit: PPM
  single-cell:
    path: single-cell.manifest.txt
    format: tsv
    genes: symbol
    deconvolution: nusvr

Options

This is a section for input multi-omics data. Four data types (transcriptome, microbiome, metabolome, single-cell) are accceptable. Options exist as below for each data type.

single-cell

  • path: Relative path to h5ad file or the manifest file (described at Input files: Omics data)

  • format: h5ad or tsv (tab-separated) or csv (comma-separated)

  • genes: Used gene identifiers Symbol or ENSG

  • deconvolution: no (not perform), nusvr (nu-Support vector machine), nnls (Non-negative least square regression)

transcriptome, microbiome, metabolome

  • path: Relative path to the table-format omics data

  • format: tsv (tab-separated) or csv (comma-separated)

  • rownames: Identifiers used as rownames of the table

    • transcriptome: Symbol, ENSG

    • microbiome: Species, Genus

    • metabolome: Name, HMDB

  • unit: Unit of the values

    • transcriptome: TPM, FPKM

    • microbiome: Ratio

    • metabolome: Name



Section: metadata

Example

metadata:
  patient:
    path: metadata.Patient.txt
    format: tsv
  sample:
    path: metadata.Sample.txt
    format: tsv
  cell:
    path: metadata.Cell.txt
    format: tsv
  samplemap:
    path: metadata.SampleMap.txt
    format: tsv
    duplicated_samples: mean

Options

This is a section for metadata. As explained in Input files: Omics data, four metadata files (patient-, sample-, cell-level metadata and samplemap) are required. Following options are necessary for each metadata.

For all metadata

  • path: Relative path to the file of metadata

  • format: tsv (tab-separated) or csv (comma-separated)

samplemap

  • duplicated_samples: How to merge multiple values from identical samples. mean or max



Section: pipeline

Example

pipeline:
  Cell-Cell:
    CORRELATE_WITH:
      methods: [Pearson, Spearman]
      level: Sample
      min_requierd_data: 20
      min_detected_ratio: 0.2
      min_correlation: 0.2
    LIGAND_RECEPTOR_COUNT:
      methods: [NATMI, LogFC]
      subsampling: 0
      top_perc: 0.01
    PHYSICALLY_INTERACT:
      methods: [Neighborseq]
      threshold: 0
  Cell-Microbe:
    CORRELATE_WITH:
      methods: [Pearson, Spearman]
      level: Sample
      min_requierd_data: 20
      min_detected_ratio: 0.2
      min_correlation: 0.2
    INTRACELLULAR_MICROBE:
      methods: [SAHMI]
      threshold: 0
  Cell-Gene:
    SPECIFICALLY_EXPRESS:
      methods: [wilcoxon]
      fdr_threshold: 0.01
      fc_threshold: 2
      rank_threshold: 3
  Cell-Metabolite:
    CORRELATE_WITH:
      methods: [Pearson, Spearman]
      level: Sample
      min_requierd_data: 20
      min_detected_ratio: 0.2
      min_correlation: 0.2
  Microbe-Microbe
    CORRELATE_WITH:
      methods: [Pearson, Spearman]
      level: Sample
      min_requierd_data: 20
      min_detected_ratio: 0.2
      min_correlation: 0.2
  Microbe-Metabolite:
    CORRELATE_WITH:
      methods: [Pearson, Spearman]
      level: Sample
      min_requierd_data: 20
      min_detected_ratio: 0.2
      min_correlation: 0.2

Available pipelines

Pipelines (RELATION TYPE)

Entity1 (FROM)

Entity2 (TO)

Directed

CORRELATE_WITH

Cell, Metabolite, Microbe

Cell, Metabolite, Microbe

No

LIGAND_RECEPTOR_COUNT

Cell

Cell

Yes

SPECIFICALLY_EXPRESS

Cell

Gene

No

DIFFERENTIAL_ABUNDANCE

Cell, Metabolite, Microbe

State*

No

DIFFERENTIAL_EXPRESSION

Cell

State*

No

PHYSICALLY_INTERACT

Cell

Cell

No

INTRACELLULAR_MICROBE

Cell

Microbe

No


Options

This section defines what analyess are performed for extraction of relationships from multi-omics data. Following options are available for each pipeline. Each pipeline returns results as edges/relationships in the knowledge graph.

CORRELATE_WITH

CORRELATE_WITH is a relationship that indicates quantities of entity X and entity Y are correlated.

  • methods: List of methods to calculate correlation. Pearson, Spearman

  • level: Sample-level correlation or Patient-level correlation. Patient is recommended if two entties are derived from different sample types of same patients (e.g., Microbiome from stool & Cell from tissue)

  • min_required_data: Minimun required number of data for correlation calculation. Calculation is skipped if number of data is below this value.

  • min_detected_ratio: Calculation is skipped if there are too many NAs (data with zeros). 20% is the threshold when the value is 0.2

  • min_correlation: Threshold for correlation coefficients. Correlations weaker than this value are not included in the result.

LIGAND_RECEPTOR

LIGAND_RECEPTOR is a relationship that indicates many ligand-receptor pairs are significantly expressed in celltype X and celltype Y.

  • methods: List of ligand-receptor analysis methods. NATMI, LogFC, CellPhoneDB

  • subsampling: Subsample N cells from each celltypes to analyze more efficiently. Subsampling is not performed if this is 0.

  • top_perc: Return top N % of significant pairs of celltypes. Top 10 % will be returned if this is 0.1.

SPECIFICALLY_EXPRESS

SPECIFICALLY_EXPRESS is a relationship that indicates that gene Y is highly expressed in celltype X than other cells.

  • methods: List of statistical tests. wilcoxon, t

  • fdr_threshold: Threshold for false discovery rate (FDR)

  • fc_threshold: Threshold for fold change between average in celltype X and average in all other cells

  • rank_threshold:

DIFFRENTIAL_ABUNDANCE

DIFFERENTIAL_ABUNDANCE is a relationship that indicates that entity X is significantly abundant in state Y. This relationship is represented as (X:)-[:DIFFERENTIAL_ABUNDANCE]-(:DifferentialTest)-[:COMPARATOR]-(Y:State) in the knowledge graph.

  • methods: List of statistical tests. wilcoxon, t

  • fdr_threshold: Threshold for false discovery rate (FDR)

  • fc_threshold: Threshold for fold change between average in celltype X and average in all other cells

DIFFRENTIAL_EXPRESSION

DIFFERENTIAL_EXPRESSION is a relationship that indicates that gene Z is differentially expressed in cell X at state Y. This relationship is represented as (X:Cell)-[:DIFFERENTIAL_EXPRESSION]-(d:DifferentialTest)-[:COMPARATOR]-(Y:State) AND (d)-[:TESTED]-(Z:Gene) in the knowledge graph.

  • methods: List of statistical tests. wilcoxon, t

  • fdr_threshold: Threshold for false discovery rate (FDR)

  • fc_threshold: Threshold for fold change between average in celltype X and average in all other cells

PHYSICALLY_INTERACT

PHYSICALLY_INTERACT is a relationship that indicates that celltype X and celltype Y has physical interaction

  • methods: List of methods. Neighbor-seq

INTRACELLULAR_MICROBE

INTRACELLULAR_MICROBE is a relationship that indicates that microbe Y is frequencly detected in celltype X than other cells.

  • methods: List of methods. SAHMI



Section: public

Example

public:
  Microbe-Metabolite:
    PRODUCE:
      sources: [gutMGene, NJC19, AGORA2]
  Metabolite-Microbe:
    CONSUME:
      sources: [gutMGene, NJC19, AGORA2]
  Gene-Metabolite:
    RECEPTOR:
      sources: [HMDB, GPCRdb]
  Microbe-Gene:
    MOLECULAR_MIMICRY:
      sources: [HMI-PRED, HPIDB]
  Gene-Gene:
    LIGAND_RECEPTOR:
      sources: [LIANA]

Available datasets

RELATION TYPE

Entity1 (FROM)

Entity2 (TO)

Directed

Source

PRODUCE

Microbe

Metabolite

Yes

gutMGene, NJC19, AGORA2, Text_minning

UPTAKE

Metabolite

Microbe

Yes

NJC19, AGORA2, Text_mining

RECEPTOR

Gene

Metabolite

Yes

HMDB, GPCRdb

ENZYME

Gene

Metabolite

Yes

HMDB, GPCRdb

MOLECULAR_MIMICRY

Microbe

Metabolite

Yes

HMI-PRED, HPIDB

LIGAND_RECEPTOR

Gene

Gene

Yes

LIANA

PRODUCE/UPTAKE

PRODUCE and UPTAKE are relationships between Microbe and Metabolite. The information is collected by two ways: (i) Metabolic modeling and (ii) Literature-based evidence.

Metabolic modeling

We predicted bacterial production and consumption of metabolites by flux variability analysis (FVA) as explained in [Magnusdottir2017]. We used AGORA2 ([Heinken2023]), collection of genome-scale metabolic models, to predict metabolic potential of >7500 human gut microbes.

Literature-based evidence

We collected literature-based information of bacterial metabolic potential from two public databases gutMGene ([Cheng2022]) and NJC19 ([Lim2020]).

RECEPTOR/ENZYME

RECEPTOR and ENZYME are relationships between Gene and Metabolite. A relationship (:Gene)<-[RECEPTOR]-(Metabolite) denotes that the gene codes receptor of the metabolite. We collected information of genes associated with metabolic reactions from public databases HMDB ([Wishart2022]) and GPCRdb ([Gaspar2023]).