Illustration of a Happy Protein with Its PTMs

AstraPTM2: A Context-Aware PTM Prediction Model for Broad-Spectrum PTMs

Full-length, context-aware PTM prediction — calibrated for discovery. AstraPTM2 combines ESM-2 embeddings, AlphaFold2 structural features, and motif-aware transformers to deliver reliable calls on 39 PTM types, from phosphorylation to sumoylation — no sequence truncation required.

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Why AstraPTM2?

AstraPTM2 runs a full-protein analysis in a single shot, scoring every residue for 39 possible modifications. Its calibrated design doesn’t just flag potential sites — it gives you confidence thresholds you can act on, revealing hidden PTM patterns and guiding downstream experiments.

Illustration Representing Multi-Label Predictions
Illustration Representing Multi-Label Predictions
Illustration Representing Multi-Label Predictions

Multi-Label Predictions

AstraPTM2 detects whether a residue is modified and classifies its type from 39 PTM labels — in a single, unified framework, in a single pass.

Illustration Representing Context Awareness
Illustration Representing Context Awareness
Illustration Representing Context Awareness

Context-Aware

Proteins are complex, and context is crucial. AstraPTM2 handles proteins of virtually any length (no windowing or truncation), preserving long-range dependencies.

Illustration Representing Discovery-Oriented
Illustration Representing Discovery-Oriented
Illustration Representing Discovery-Oriented

Discovery-Oriented

By leveraging robust context-awareness, a large training dataset, and dual modes, AstraPTM2 allows users to separate high-confidence actionable calls from hypothesis-generating lower-confidence sites.

Proven Performance Across 39 PTMs

AstraPTM2 achieves macro-F1=59% and AUROC=99% across 39 PTM types — from phosphorylation and ubiquitination to rare labels like lactylation. Calibrated outputs deliver actionable, residue-level predictions ready for experimental use.

Orbion's AstraPTM2 Machine Learning Model's PTM Predictions on an Example Protein
Orbion's AstraPTM2 Machine Learning Model's PTM Predictions on an Example Protein
Orbion's AstraPTM2 Machine Learning Model's PTM Predictions on an Example Protein

Next-Generation Architecture

Built on a transformer backbone with multi-scale convolutions and global gating, AstraPTM2 captures both local motifs and global context. Trained on 100k+ proteins with ESM2 embeddings and AlphaFold2 features, it generalizes across common and rare PTMs.

Orbion's AstraPTM2 Machine Learning Model's Inference Flow Diagram
Orbion's AstraPTM2 Machine Learning Model's Inference Flow Diagram
Orbion's AstraPTM2 Machine Learning Model's Inference Flow Diagram

See AstraPTM2 in action.

Curious how AstraPTM2 streamlines PTM identification from a simple sequence input? Book a demo, and let us showcase you how to harness AstraPTM2's capabilities for your research.