Serine protease inhibitor Kazal-type 2 (SPINK2) is a 84-residue protein from Homo sapiens. This is its AlphaFold structure prediction, created 1 Aug 2025. UniProt accession: P20155.
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The mean pLDDT of this model is 85.6 (confident overall). pLDDT is AlphaFold's per-residue confidence score from 0 to 100. In MolViewer, choose the B-factor color scheme to color the model by pLDDT, because AlphaFold stores it in the B-factor column.
| pLDDT band | Meaning | Share of residues |
|---|---|---|
| Above 90 | Very high: backbone and side chains are usually accurate | 52% |
| 70 to 90 | Confident: backbone generally right | 32% |
| 50 to 70 | Low: treat with caution | 16% |
| Below 50 | Very low: often disordered regions | 0% |
What pLDDT means and how to read it
As a strong inhibitor of acrosin, it is required for normal spermiogenesis. It probably hinders premature activation of proacrosin and other proteases, thus preventing the cascade of events leading to spermiogenesis defects (PubMed:28554943). May be involved in the regulation of serine protease-dependent germ cell apoptosis (By similarity). It also inhibits trypsin
Secreted, Cytoplasmic vesicle, secretory vesicle, acrosome
Compare the prediction with experimentally determined structures of the same protein:
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