AACompIdent

AACompIdent identifies proteins by comparing amino acid composition, isoelectric point (pI), and molecular weight (Mw) to database entries to support protein identification from 2-D electrophoresis and proteomics analyses.

Key Features:

• Amino acid composition analysis: Compares experimental amino acid composition to database entries to identify candidate proteins.
• Integration of multiple parameters: Incorporates isoelectric point (pI), molecular weight (Mw), species-specific data, and UniProtKB keywords to refine identifications.
• Calibration protein support: Uses calibration proteins to improve estimations of pI and Mw for more accurate matching.
• Database matching (SWISS-PROT): Matches compositions and parameters against entries in SWISS-PROT to retrieve candidate protein identities.
• Scoring and validation: Generates distinct score patterns for correct versus incorrect identifications to support validation of results.

Scientific Applications:

• Protein-based gene expression analysis: Identifies proteins from 2-D electrophoresis gels to support comparative expression studies across organisms, tissues, and disease states.
• Identification of unknown proteins: Provides score-based candidate lists to prioritize proteins for sequencing or other confirmatory analyses.
• Large-scale proteome screening: Enables cataloging of protein complements of simple organisms or complex tissues through composition-based matching.

Methodology:

Matches amino acid composition, pI, and Mw of experimental samples against database entries (SWISS-PROT/UniProtKB), incorporates species-specific data and UniProtKB keywords, uses calibration proteins for pI/Mw estimation, and produces score patterns distinguishing correct and incorrect identifications.