The gene encoding the blue-copper protein amicyanin was isolated from a genomic bank of Pracoccus denitrificans by using a synthetic oligonucleotide. It is located directly downstream of the gene encoding the small subunit of methylmine dehydrogenase. Amicyanin is transcribed as a presursor protein with a signal sequence, typical for periplasmic proteins. Specific inactivation of amicyanin by means of gene replacement techniques resulted in the complete loss of the ability to grow on methylamine.
