Figure 2.

Alignment of the two glnB-like genes of Methanosarcina mazei located in the nif gene cluster, compared with the corresponding glnB-like genes in Methanococcus maripaludis, Methanosarcina barkeri and Clostridium acetobutylicum, and glnB from Klebsiella pneumoniae. The predicted secondary structural elements, the T-loop and the B-loop, are indicated above the sequence. The boxed areas show the tyrosine residue (Tyr51) that is the conserved site of uridylylation in bacteria and the corresponding amino acid residues of the glnB-like genes at position 51.