checku 0.1.2

CheckU: UNI56 marker completeness profiling for microbial genomes.

CheckU

CheckU evaluates bacterial and archaeal genomes with the UNI56 universal single-copy marker set. The program reads amino acid FASTA files or nucleotide assemblies, calls genes with Pyrodigal when needed, and scores markers with PyHMMER. Results include completeness, contamination, and per-marker hit tables.

Requirements

• Linux x86_64 with enough CPU and RAM for HMMER searches
• FASTA inputs in plain or gzip form (.faa, .fa, .fna, and friends)

Installation

Option 1: pip (PyPI)

pip install checku

Option 2: Pixi (development)

pixi install

Quick Check

checku --help

If you are running from the repository with Pixi:

pixi run python -m checku --help

You should see the command line help without errors.

Input Rules

• Provide either a single FASTA file or a directory of FASTA files.
• Protein files are used as-is. Nucleotide files trigger Pyrodigal gene calls.
• Compressed files (.gz) are supported; they are unpacked into the run workspace.

Running The Pipeline

If you are running from the repository with Pixi, replace checku below with pixi run python -m checku.

Pipeline Overview

The diagram below shows the main stages executed by CheckU.

graph TD
    A([Start run]) --> B[Collect FASTA inputs from file or directory]
    B --> C[Materialize gzipped files under `work/` when needed]
    C --> D{Detect sequence type}
    D -->|Protein| E[Use supplied protein FASTA]
    D -->|Nucleotide| F[Predict proteins with Pyrodigal]
    F --> E
    E --> G[Search UNI56 HMMs with pyhmmer]
    G --> H[Aggregate marker hits and completeness statistics]
    H --> I[Write `checku_summary.tsv`]
    H --> J[Write `details/checku_presence.tsv`]
    H --> K[Write raw hit tables in `details/hits/`]
    H --> L[Update checkpoint data and logs]
    H -.-> M[Optional: delete predicted proteins when `--clean-intermediate`]
    I --> N([Pipeline complete])
    J --> N
    K --> N
    L --> N
    M --> N

Single Proteome

checku run \
  data/test_genomes/faa/IMGI2140918011.faa \
  --output-dir tmp/proteome_example \
  --cpus 4

Directory Of Proteomes

checku run \
  data/test_genomes/faa \
  --output-dir tmp/proteome_batch \
  --cpus 8

Single Assembly

checku run \
  data/test_genomes/fna/IMG2140918011.fna \
  --output-dir tmp/assembly_example \
  --cpus 4 \
  --clean-intermediate

Use --clean-intermediate if you do not need the predicted protein FASTA after the run.

Custom Marker Sets

• The default marker file ships with CheckU (UNI56).
• Point --hmm to a different GA-calibrated .hmm file or to a directory that holds .hmm or .hmm.gz profiles.
• Every profile must define GA cutoffs. The run stops early if a profile is missing them or if names are duplicated.

Example:

checku run \
  /path/to/genomes \
  --hmm /path/to/custom_markers.hmm \
  --output-dir tmp/custom_markers \
  --cpus 8

Outputs

All outputs live in the chosen --output-dir.

• checku_summary.tsv — per-genome summary with completeness, contamination, duplicate counts, and Pyrodigal gene statistics.
• details/checku_presence.tsv — marker presence/absence matrix.
• details/hits/*.tsv — raw pyhmmer hits with domain scores.
• checkpoint/checku_checkpoint.json — resume data for interrupted runs.
• logs/checku.log — timestamps, command line, and status messages.

Resume And Logging

• Runs resume automatically when --resume is left on (default).
• Use --no-resume to start fresh; the older checkpoint is copied aside.
• Increase --log-level to DEBUG when you need extra detail.

Verification Step

Small test data sets are stored under data/test_genomes/. After installation you can confirm the pipeline by running:

checku run data/test_genomes/faa --output-dir tmp/test_run --cpus 2

The command should finish without errors and produce the summary and presence tables described above.