Timo Saratto

@timosaratto.bsky.social

Software engineering and microbial genomics 🇫🇮

The headlines are still covering the cyclosporiasis outbreak from lettuce, but let's talk about a different summer, long ago. The headlines in Bavaria would have called it "summer diarrhea" & it was killing babies. Enter our hero, Professor Theodor Escherich of the Julius Hospital, Würzburg.

Signed portrait of Theodor Escherich, MD (1857-1911). Dr. Escherich was a German-Austrian pediatrician, best known for his discovery of the Escherichia coli bacterium

Targeted #metagenomics isn't a new problem and is solvable at the bench. In 2013, this group elegantly used Single Chain antibodies to enrich species of interest. This makes enrichment an antigen-selection problem (trivial), where only n=50 cells required for 99% coverage doi.org/10.1186/1471...

Using phage display selected antibodies to dissect microbiomes for complete de novo genome sequencing of low abundance microbes - BMC Microbiology

Background Single cell genomics has revolutionized microbial sequencing, but complete coverage of genomes in complex microbiomes is imperfect due to enormous variation in organismal abundance and amplification bias. Empirical methods that complement rapidly improving bioinformatic tools will improve characterization of microbiomes and facilitate better genome coverage for low abundance microbes. Methods We describe a new approach to sequencing individual species from microbiomes that combines antibody phage display against intact bacteria with fluorescence activated cell sorting (FACS). Single chain (scFv) antibodies are selected using phage display against a bacteria or microbial community, resulting in species-specific antibodies that can be used in FACS for relative quantification of an organism in a community, as well as enrichment or depletion prior to genome sequencing. Results We selected antibodies against Lactobacillus acidophilus and demonstrate a FACS-based approach for identification and enrichment of the organism from both laboratory-cultured and commercially derived bacterial mixtures. The ability to selectively enrich for L. acidophilus when it is present at a very low abundance (<0.2%) leads to complete (>99.8%) de novo genome coverage whereas the standard single-cell sequencing approach is incomplete (<68%). We show that specific antibodies can be selected against L. acidophilus when the monoculture is used as antigen as well as when a community of 10 closely related species is used demonstrating that in principal antibodies can be generated against individual organisms within microbial communities. Conclusions The approach presented here demonstrates that phage-selected antibodies against bacteria enable identification, enrichment of rare species, and depletion of abundant organisms making it tractable to virtually any microbe or microbial community. Combining antibody specificity with FACS provides a new approach for characterizing and manipulating microbial communities prior to genome sequencing.

doi.org

New work on using transformers (using gene order) for tasks in genomic epidemiology: www.biorxiv.org/content/10.6... We trained BART models (w/ extended context windows) on E.coli and S.pneumo from AllTheBacteria and tested if the model could find new strains, insertions (blaCTX-M) and co-selection

Embeddings of gene order from PanBART model
Sam Horsfield@samuelhorsfield.bsky.social · 5mo ago

Our new preprint is out! We train a transformer on gene order and gene content of bacterial pathogens, applying it to a range of epidemiological and evolutionary analyses (1/8) www.biorxiv.org/content/10.6...

Can't wait to release a 10-year-old birthday version for SeqKit! - 10 years - 2 papers, 3500 citations - 20 contributors - 40 subcommands - 880 commits - 500 issues - 685.5K Bioconda total downloads Thank you all, dear contributors and users! I'll keep maintaining it. github.com/shenwei356/s...

Release SeqKit v2.13.0 (10-year-old birthday version) · shenwei356/seqkit

Changelog SeqKit is 10 years old! SeqKit v2.13.0 - 2026-02-28 seqkit: add support for reading and writing LZ4 compression format. new command: seqkit sample2: improved seqkit sample by @stahiga....

github.com

🗜️⚡ If you use gzip/gunzip a lot in your pipelines, switch to the faster"libdeflate" versions instead! They use modern CPU capabilities to achieve a 2-3x speedup. libdeflate is in conda, and "libdeflate-gzip" and "libdeflate-gunzip" are drop-in replacements. #unix github.com/ebiggers/lib...

GitHub - ebiggers/libdeflate: Heavily optimized library for DEFLATE/zlib/gzip compression and decompression

Heavily optimized library for DEFLATE/zlib/gzip compression and decompression - ebiggers/libdeflate

github.com