Protein sequencing nucleotides compared

There are three varieties of translated BLAST search tblastn, blastx, and tblastx. In the first variant, tblastn, a protein sequence query is compared to the six-frame translations of the sequences in a nucleotide database. In the second variant, blastx, a nucleotide sequence query is translated in six reading frames, and the resulting six-protein sequences are compared, in turn, to those in a protein sequence database. In the third variant, tblastx, both the query and database subject nucleotide sequences are translated in six reading frames, after which 36 (6 x 6) protein blastp comparisons are made. Protein sequences... 

Gotoh O. Substrate recognition sites in cytochrome P450 family 2 (CYP2) proteins inferred from comparative analyses of amino acid and coding nucleotide sequences. J Biol Chem 1992 267(1) 83-90. 

BLAST2Sequences is used to compare two sequences, protein or nucleotide, using any one of the principal BLAST variants, blastp, blastn, tblastn, blastx, tblastx, or MegaBLAST. 

The mass profile is then compared with peptide masses predicted from theoretical digestion of known protein sequences contained within current protein databases or predicted from nucleotide sequence databases. This approach proves very effective when trying to identify proteins from species... 

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