The recently determined structure of octameric mitochondrial creatine
kinase has provided new insights into the functioning of this enzyme a
nd its role in channelling energy from the mitochondria to the cytopla
sm. Creatine kinase, a member of the family of guanidino kinases, is s
tructurally similar to glutamine synthetase, suggesting a possible evo
lutionary link between both protein families. (C) Current Biology Ltd
ISSN 0959-440X.