Structure of Enhanced Database. Consensus protein sequences NP_775259 (first line, residues 480 – 510 shown) and NP_076410 (second and third lines, residues 81 – 170 shown) are used as examples to demonstrate the structure of our sequence file, part of the enhanced database. A "[" character is always inserted after the last amino acid of each protein to serve as a separator. Annotated SAPs and PTMs associated with an amino acid are included in a pair of angular brackets following that amino acid. SAPs are further enclosed by a pair of curly brackets while PTMs are further enclosed by a pair of round brackets. Amino acid followed by two zeros indicates an annotated SAP. Every annotated PTM has a two-digit positive integer that is used to distinguish different modifications.