EC Number   |
General Information |
Reference |
|---|
    6.3.1.21 | evolution |
PurT is reported to have 27% amino acid sequence similarity with PurK but none with PurN |
761368 |
| 6.3.1.21 | evolution |
The purT encoded glycinamide ribonucleotide transformylase differs from the previously known purN encoded enzyme in size, sequence, and substrates, and ATP and formate are required as opposed to formyl tetrahydrofolate |
760556 |
| 6.3.1.21 | evolution |
the PurT transformylase belongs to the ATP-grasp superfamily of proteins. The common theme among members of this superfamily is a catalytic reaction mechanism that requires ATP and proceeds through an acyl phosphate intermediate. All of the enzymes belonging to the ATP-grasp superfamily are composed of three structural motifs, termed the A-, B-, and C-domains, and in each case, the ATP is wedged between the B- and C-domains. Superposition of the Rossmann folds found in UDP-galactose 4-epimerase and PurT transformylase, overview |
760559 |
| 6.3.1.21 | malfunction |
mutants defective in synthesis of purN- and purT-encoded enzymes are isolated. Only strains defective in both genes require an exogenous purine source for growth. Determination of GAR transformylase T activity in vitro requires formate as the Cl donor. Growth of purN mutants is inhibited by glycine. Under these conditions GAR accumulates. Addition of purine compounds or formate prevents growth inhibition |
761366 |
| 6.3.1.21 | malfunction |
on the basis of the growth of purU, purN, and purU/purN mutants, it appears that PurU provides the major source of formate for the purT-dependent synthesis of 5'-phosphoribosyl-N-formylglycinamide (FGAR). Mutations in either of two pairs of genes are required to block synthesis of FGAR from GAR: purN/purT (purT encodes an alternative formate-dependent GAR transformylase) or purN/purU |
761368 |
| 6.3.1.21 | malfunction |
PurT transformylase mutant G162I catalyzes the production of formyl GAR two orders of magnitude less efficiently than the wild-type enzyme. This reduced rate is apparently sufficient to sustain cell growth under limiting purine conditions |
760556 |
| 6.3.1.21 | malfunction |
single mutants of Salmonella enterica serovar Typhimurium strain 4/74, created by deletion of the purN and purT genes, grow as well as the parental wild-type strain in minimal medium, while the double mutant does not grow. Mutation of purN but not purT attenuates the strain during interaction with cultured macrophages. Growth phenotypes of mutants in murine J774A.1 macrophages, overview |
-, 761243 |
| 6.3.1.21 | metabolism |
formate is produced from fTHF by the enzyme PurU |
-, 761243 |
| 6.3.1.21 | metabolism |
purN- and purT-encoded enzymes are required for synthesis of N2-formyl-N1-(5-phospho-beta-D-ribosyl)glycinamide, both enzymes may function to ensure normal purine biosynthesis. Regulation of the level of GAR transformylase T is controlled by the PurR protein and hypoxanthine. The GAR transformylase T-catalyzed reaction might provide a pathway by which formate is utilized or rescued as a C1 unit, and the activity of the two different GAR transformylases might be determined by the availability of the cofactors, formate and 10-formyl-THF |
761366 |
| 6.3.1.21 | metabolism |
PurT glycinamide ribonucleotide (GAR) transformylase is an alternative to the formyl-folate utilizing purN GAR transformylase. No significant homology exists between the two transformylases. But the PurT protein shows significant homology to the PurK protein, also involved in purine biosynthesis |
760555 |
