Pathways & interactions
Nitrogen regulatory PII-like, alpha/beta (IPR011322)
Short name: N-reg_PII-like_a/b
- Nitrogen regulatory protein PII (IPR002187)
- Domain of unknown function DUF190 (IPR003793)
- Divalent ion tolerance protein, CutA (IPR004323)
- Cyclic-di-AMP receptor (IPR010375)
- Histidine biosynthesis HisG, C-terminal (IPR013115)
- Nitrogen regulatory protein PII/ATP phosphoribosyltransferase, C-terminal (IPR015867)
- Uncharacterised protein family, nitrogen regulatory protein PII-related (IPR019296)
- ATP phosphoribosyltransferase HisG, long form (IPR020621)
- Divalent cation tolerance protein CutA, Enterobacteria (IPR023700)
- Uncharacterised conserved protein UCP005637 (IPR024184)
This superfamily represents a structural domain found in the nitrogen regulatory protein PII, in ATP phosphribosyltransferases (C-terminal domain), in the divalent ion tolerance protein CutA1, and in some bacterial hypothetical proteins. This domain consists of a ferredoxin-like alpha/beta sandwich, which forms trimeric structures with orthogonally packed beta-sheets around a three-fold axis.
PII is a tetrameric protein encoded by glnB that functions as a component of the adenylation cascade involved in the regulation of GS activity [PMID: 1702507]. PII helps regulate the level of glutamine synthetase in response to nitrogen source availability. In nitrogen-limiting conditions, PII is uridylylated to form PII-UMP, which allows the deadenylation of glutamine synthetase, thus activating the enzyme. Conversely, in nitrogen excess, PI-UMP is deuridylated to PII, promoting the adenylation and deactivation of glutamine synthetase [PMID: 16860774].
ATP phosphoribosyltransferase is the first enzyme of the histidine pathway. It is allosterically regulated, controlling the flow of intermediates through the pathway. The C-terminal domain is the regulatory region of the protein, which binds the allosteric inhibitor histidine [PMID: 14741209].
CutA1 functions in divalent ion tolerance in bacteria, plants and animals [PMID: 12949080, PMID: 7623666]. Divalent metal ions play key roles in all living organisms, serving as cofactors for many proteins involved in a variety of electron-transfer activities. In Escherichia coli it is thought to be involved in copper ion tolerance, excessive copper ions being toxic [PMID: 17077491].
- SSF54913 (SSF54913)