Adenylylrelated

Adenylyl-related is a broad descriptor for biochemical processes, enzymes, and molecules that involve the adenylyl group (AMP). It covers reactions in which an AMP moiety is transferred to a substrate (adenylylation or AMPylation), enzymes that produce AMP-containing products, and pathways that use adenylyl-containing cofactors such as cyclic AMP. In practice, "adenylyl-related" is often used to group activities associated with adenylyl transferases, AMP modification, and RNA or protein adenylation.

Adenylyl transferases constitute a large and diverse enzyme class that mediate the transfer of an adenylyl group from ATP to a substrate. A prominent example is adenylyl cyclase, which converts ATP into cyclic AMP (cAMP), a key second messenger. Other enzymes act as general nucleotidyl transferases adding AMP to RNA (poly(A) polymerases) or to proteins (AMPylators). The term also encompasses enzymes that attach AMP to various biomolecules, sometimes forming noncanonical linkages that regulate function.

Adenylylation or AMPylation describes the covalent attachment of an AMP moiety to a target molecule, often a protein. This regulatory modification is performed by Fic-domain proteins in bacteria and eukaryotes and can alter enzyme activity, interactions, or localization. In host-pathogen interactions, bacterial effectors use AMPylation to disrupt signaling. In cells, AMPylation is increasingly recognized as a regulatory post-translational modification in signaling networks, with ongoing research clarifying its reversibility and control mechanisms.

Beyond signaling, adenylyl-related chemistry is central to RNA metabolism, with poly(A) polymerases adding polyadenylate tails to mRNA and other nucleotidyltransferases shaping RNA stability and translation. The study of adenylyl-related processes spans metabolism, cell signaling, and gene expression, and researchers continue to map the full diversity and regulation of AMP transfer across organisms.