Fold: Class II aaRS and biotin synthetases

contains large mixed beta-sheet

Lineage:

1. Root: scop
2. Class: Alpha and beta proteins (a+b)
   Mainly antiparallel beta sheets (segregated alpha and beta regions)
3. Fold: Class II aaRS and biotin synthetases
   contains large mixed beta-sheet

Superfamilies:

1. Class II aaRS and biotin synthetases (2)
   1. Class II aminoacyl-tRNA synthetase (aaRS)-like, catalyic domain (15)
   2. Biotin holoenzyme synthetase (1)