Identification of proteins involved in formaldehyde metabolism by Rhodobacter sphaeroides.

Formaldehyde is an intermediate formed during the metabolism of methanol or other methylated compounds. Many Gram-negative bacteria generate formaldehyde from methanol via a periplasmic pyrroloquinoline quinone (PQQ)-dependent dehydrogenase in which the alpha subunit of an alpha(2)beta(2) tetramer has catalytic activity. The genome of the facultative formaldehyde-oxidizing bacterium Rhodobacter sphaeroides encodes XoxF, a homologue of the catalytic subunit of a proposed PQQ-containing dehydrogenase of Paracoccus denitrificans.