Siginificant Homology at the Amino acid level? - Gene sequence homology (Apr/18/2008 )

I belive I have identified an operon in the bacteria Acinetobacter baumannii but the % of identity at the aminoacid level of the genes goes from 24-54%. Is this significant, what would a minimum aceptable of identity at the aminoacid level?. Tha nk you so much. Tom

is this 24-54% identity located in conserved domains or distributed randomly along the subject? if the case is the first i'd say it is significant, if not then don't keep your hopes too high.
cheers.
tj