Pertaining to proteins within cells or tissues.

Relating to internal protein structures in organisms.

Characterizing enzymes that function inside living cells.

Describing cellular components composed of soluble proteins.

**Endoproteinaceous substance**: Proteins that are part of living organisms.

**Endoproteinaceous material**: Biomolecules derived from proteins within cells.

**Endoproteinaceous component**: Protein-based elements in biological structures or functions.