Ortholog search

What is the relevance of genome sequences to the search for biocatalytically applicable enzymes At least two different avenues, in this context called ortholog search and paralog search have the potential to yield results that are immediately useful. 

Table 1 Searching for the 10 Closest Human Orthologs of the C. elegans Y22D7AR 13 Gene Product...

Figure 6.13 BLAST search results. Part of the results from a BLAST search of the nonredundant (nr) protein sequence database with the use of the sequence of ribose-5-phosphate isomerase (also called phosphopentose isomerase, pp. 572 and S81) from coli as a query. Among the 268 sequences found is the orthologous sequence from human beings, and the alignment between these sequences is shown (highlighted in yellow). The number of sequences with this level of similarity expected to be in the database by chance is 2 X 10 as shown by the E value (highlighted in red). Because this value is much less than 1, the observed sequence alignment is highly significant.

The second step was to gather orthologous sequences of BACE to define the family of sequences to which BACE belongs. We searched both the non-redundant protein sequence database at NCBI as well as the EST databases. The resulting alignment of BACE orthologues is shown in Figure 5.3... 

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