The crystal structure of protein MJ1225 from Methanocaldococcus jannaschii shows strong conservation of key structural features seen in the eukaryal gamma-AMPK.
Primary Citation of Related Structures:   3KH5, 3LFZ
PubMed Abstract: 
In mammals, 5'-AMP-activated protein kinase (AMPK) is a heterotrimeric protein composed of a catalytic serine/threonine kinase subunit (alpha) and two regulatory subunits (beta and gamma). The gamma-subunit senses the intracellular energy status by competitively binding AMP and ATP and is thought to be responsible for allosteric regulation of the whole complex ...
In mammals, 5'-AMP-activated protein kinase (AMPK) is a heterotrimeric protein composed of a catalytic serine/threonine kinase subunit (alpha) and two regulatory subunits (beta and gamma). The gamma-subunit senses the intracellular energy status by competitively binding AMP and ATP and is thought to be responsible for allosteric regulation of the whole complex. We describe herein the crystal structure of protein MJ1225 from Methanocaldococcus jannaschii complexed to AMP, ADP, and ATP. Our data provide evidence of a strong conservation of the key functional features seen in the gamma-subunit of the eukaryotic AMPK, and more importantly, it reveals a novel AMP binding site, herein denoted as site E, which had not been previously described in cystathionine beta-synthase domains so far. Site E is located in a small cavity existing between the alpha-helices structurally equivalent to those disrupting the internal symmetry of each Bateman domain in gamma-AMPKs and shows striking similarities with a symmetry-related crevice of the mammalian enzyme that hosts the pathological mutation N488I.
Related Citations: 
Purification, crystallization and preliminary crystallographic analysis of protein MJ1225 from Methanocaldococcus jannaschii, a putative archaeal homologue of gamma-AMPK. Gomez Garcia, I., Kortazar, D., Oyenarte, I., Mato, J.M., Martinez-Chantar, M.L., Martinez-Cruz, L.A. (2009) Acta Crystallogr Sect F Struct Biol Cryst Commun 65: 813
Organizational Affiliation: 
Structural Biology Unit, CIC bioGUNE, Parque Tecnológico de Bizkaia, Edificio 800, 48160 Derio, Bizkaia, Spain.