>1bt7A (A:) observed residues (from ATOM records)
tgrdknqvegevqvvstatqsflatcvngvcwtvyhgagsktlagpkgpitqmytnvdqd
lvgwqappgarsltpctcgssdlylvtrhadvipvrrrgdsrgsllsprpvsylkgssgg
pllcpsghavgifraavctrgvakavdfvpvesmettmraskkkk