Fold: Glutamine synthase/guanidino kinase catalytic domain

Lineage:

1. Root: scop
2. Class: Alpha and beta proteins (a+b)
   Mainly antiparallel beta sheets (segregated alpha and beta regions)
3. Fold: Glutamine synthase/guanidino kinase catalytic domain

Superfamilies:

1. Glutamine synthase/guanidino kinase catalytic domain (2)
   duplication: common core consists of two beta-alpha-beta2-alpha repeats
   1. Glutamine synthetase, C-terminal domain (1)
   2. Guanido kinases (6)