The invention relates to a phytase derived from Citrobacter braakii and
related phytases. The phytases belong to the acid histidine phosphatase
family, are acid-stable, of an excellent performance in animal feed, of a
high specificity towards the substrate phytate, and expectedly of a high
specific activity. The invention also relates to the corresponding DNA,
the recombinant and wild-type production of the phytases, as well as the
use thereof.