It denotes the presence of both alpha-helical transmembrane regions and the membrane spanning regions of beta-barrel transmembrane proteins. / Processing section describes a propeptide, which is a part of a protein that is cleaved during maturation or activation.
Once cleaved, a propeptide generally has no independent biological function.
PHM share protein sequence similarity with dopamine-beta-monooxygenases (DBH), a class of ascorbate-dependent enzymes that requires copper as a cofactor and uses ascorbate as an electron donor.
PHM and DBH share a few regions of sequence similarity, some of which contain clusters of conserved histidine residues that may be involved in copper binding [PMID: 11028916, PMID: 16301310].
Conclusion: PAM-dependent amidation has the potential to signal oxygen levels in the same range as the hypoxia-inducible factor (HIF) system.
Significance: Physiological effects of hypoxia may be PAM-dependent.
Background: Peptidylglycine alpha-Amidating Monooxygenase (PAM) is solely responsible for catalysis of amidation, a biologically important post-translational modification.
The Drosophila genome predicts expression of one monofunctional PHM gene and two monofunctional PAL genes [PMID: 15198673].
It lists the nodes as they appear top-down in the taxonomic tree, with the more general grouping listed first. This subsection of the “Names and Taxonomy” section is present for entries that are part of a proteome, i.e.
of a set of proteins thought to be expressed by organisms whose genomes have been completely sequenced. This subsection of the ‘Subcellular location’ section describes the extent of a membrane-spanning region of the protein.
The monooxygenase part produces an unstable peptidyl(2-hydroxyglycine) intermediate that is dismutated to glyoxylate and the corresponding desglycine peptide amide by the lyase part.
C-terminal amidation of peptides such as neuropeptides is essential for full biological activity.