Protein Family Models

This is a family of bifunctional uridylyl-removing enzymes/uridylyltransferases (UR/UTases, GlnD) that are responsible for the modification (EC:2.7.7.59) of the regulatory protein P-II, or GlnB (e.g. Swiss:P05826, Pfam:PF00543). In response to nitrogen limitation, these transferases (e.g. Swiss:P27249) catalyse the uridylylation of the PII protein, which in turn stimulates deadenylylation of glutamine synthetase (GlnA). Deadenylylated glutamine synthetase is the more active form of the enzyme [1]. Moreover, uridylylated PII can act together with NtrB and NtrC to increase transcription of genes in the sigma54 regulon, which include glnA and other nitrogen-level controlled genes [2]. It has also been suggested that the product of the glnD gene is involved in other physiological functions such as control of iron metabolism in certain species [2]. The region described in this family is found in many of its members to be C-terminal to a nucleotidyltransferase domain (Pfam:PF01909), and N-terminal to an HD domain (Pfam:PF01966) and two ACT domains (Pfam:PF01842) [3]. [1]. 8412694. The genes of the glutamine synthetase adenylylation cascade are not regulated by nitrogen in Escherichia coli. van Heeswijk WC, Rabenberg M, Westerhoff HV, Kahn D;. Mol Microbiol 1993;9:443-457. [2]. 10931314. Novel effects of a transposon insertion in the Vibrio fischeri glnD gene: defects in iron uptake and symbiotic persistence in addition to nitrogen utilization. Graf J, Ruby EG;. Mol Microbiol 2000;37:168-179. [3]. 12384297. Isolation and characterization of the glnD gene of Gluconacetobacter diazotrophicus, encoding a putative uridylyltransferase. TRUNCATED at 1650 bytes (from Pfam)

Date:

2024-10-16

HD domains are metal dependent phosphohydrolases. [1]. 9868367. The HD domain defines a new superfamily of metal-dependent phosphohydrolases. Aravind L, Koonin EV;. Trends Biochem Sci 1998;23:469-472. (from Pfam)

Date:

2024-10-16

This family of domains generally have a regulatory role. ACT domains are linked to a wide range of metabolic enzymes that are regulated by amino acid concentration. Pairs of ACT domains bind specifically to a particular amino acid leading to regulation of the linked enzyme. The ACT domain is found in: D-3-phosphoglycerate dehydrogenase EC:1.1.1.95 Swiss:P08328, which is inhibited by serine [1]. Aspartokinase EC:2.7.2.4 Swiss:P53553, which is regulated by lysine. Acetolactate synthase small regulatory subunit Swiss:P00894, which is inhibited by valine. Phenylalanine-4-hydroxylase EC:1.14.16.1 Swiss:P00439, which is regulated by phenylalanine. Prephenate dehydrogenase EC:4.2.1.51 Swiss:P21203. formyltetrahydrofolate deformylase EC:3.5.1.10, Swiss:P37051, which is activated by methionine and inhibited by glycine. GTP pyrophosphokinase EC:2.7.6.5 Swiss:P11585 [1]. 7719856. The allosteric ligand site in the Vmax-type cooperative enzyme phosphoglycerate dehydrogenase. Schuller DJ, Grant GA, Banaszak LJ;. Nat Struct Biol 1995;2:69-76. Definition of the domain. [2]. 10222208. Gleaning non-trivial structural, functional and evolutionary information about proteins by iterative database searches. Aravind L, Koonin EV;. J Mol Biol 1999;287:1023-1040. (from Pfam)

Date:

2024-10-16

Members of this family belong to a large family of nucleotidyltransferases [1]. This family includes kanamycin nucleotidyltransferase (KNTase) which is a plasmid-coded enzyme responsible for some types of bacterial resistance to aminoglycosides. KNTase in-activates antibiotics by catalysing the addition of a nucleotidyl group onto the drug. [1]. 7482698. DNA polymerase beta belongs to an ancient nucleotidyltransferase superfamily. Holm L, Sander C;. Trends Biochem Sci 1995;20:345-347. (from Pfam)

Date:

2024-10-16

bifunctional uridylyltransferase/uridylyl-removing enzyme modifies, by uridylylation and deuridylylation, the PII regulatory proteins GlnB and GlnK, in response to the nitrogen status of the cell

Date:

2018-03-01

Catalyzes the uridylylation or deuridylylation of the PII nitrogen regulatory protein

Gene:

glnD

Date:

2024-05-02

Gene:

glnD

Date:

2020-10-26

This HMM describes GlnD, the uridylyltransferase/uridylyl-removing enzyme for the nitrogen regulatory protein PII. Not all homologs of PII share the property of uridylyltransferase modification on the characteristic Tyr residue (see Prosite pattern PS00496 and document PDOC00439), but the modification site is preserved in the PII homolog of all species with a member of this family.

Gene:

glnD

Date:

2021-04-27