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Global and Local Alignments in practice

As you've seen, when aligning two sequences, the alignment can be either global or local. While the global alignment always includes both sequences from beginning to end, the local alignment can cover just a shorter stretch of the full sequences.

The two proteins O77266 and O69363 both contain a Rieske [2Fe-2S] domain but have otherwise unrelated sequences. Download the sequences from their ``Niceprot pages'' (look for the ``in fasta format'' link) and do both a global and a local alignment with the programs needle and water respectively.

Compare the resulting alignments and discuss the biological meaning of these.
Hint:Look at the Rieske domain locations: O77266 O69363


Credit to Olof Karlberg, Dept. Mol. Evol., Uppsala



David Ardell 2005-01-27