1KJ9

Crystal structure of purt-encoded glycinamide ribonucleotide transformylase complexed with Mg-ATP

Summary for 1KJ9

• Entry DOI: 10.2210/pdb1kj9/pdb
• Descriptor: phosphoribosylglycinamide formyltransferase 2, MAGNESIUM ION, SODIUM ION, ... (8 entities in total)
• Functional Keywords: atp-grasp, purine biosynthesis, nucleotide, transferase
• Biological source: Escherichia coli
• Total number of polymer chains: 2
• Total formula weight: 86533.12

Authors

Thoden, J.B.,Firestine, S.M.,Benkovic, S.J.,Holden, H.M. (deposition date: 2001-12-04, release date: 2002-06-28, Last modification date: 2023-08-16)

Primary citation

Thoden, J.B.,Firestine, S.M.,Benkovic, S.J.,Holden, H.M.
PurT-encoded glycinamide ribonucleotide transformylase. Accommodation of adenosine nucleotide analogs within the active site.
J.Biol.Chem., 277:23898-23908, 2002

PubMed Abstract: PurT-encoded glycinamide ribonucleotide transformylase, or PurT transformylase, functions in purine biosynthesis by catalyzing the formylation of glycinamide ribonucleotide through a catalytic mechanism requiring Mg(2+)ATP and formate. From previous x-ray diffraction analyses, it has been demonstrated that PurT transformylase from Escherichia coli belongs to the ATP-grasp superfamily of enzymes, which are characterized by three structural motifs referred to as the A-, B-, and C-domains. In all of the ATP-grasp enzymes studied to date, the adenosine nucleotide ligands are invariably wedged between the B- and C-domains, and in some cases, such as biotin carboxylase and carbamoyl phosphate synthetase, the B-domains move significantly upon nucleotide binding. Here we present a systematic and high-resolution structural investigation of PurT transformylase complexed with various adenosine nucleotides or nucleotide analogs including Mg(2+)ATP, Mg(2+)-5'-adenylylimidodiphosphate, Mg(2+)-beta,gamma-methyleneadenosine 5'-triphosphate, Mg(2+)ATPgammaS, or Mg(2+)ADP. Taken together, these studies indicate that the conformation of the so-called "T-loop," delineated by Lys-155 to Gln-165, is highly sensitive to the chemical identity of the nucleotide situated in the binding pocket. This sensitivity to nucleotide identity is in sharp contrast to that observed for the "P-loop"-containing enzymes, in which the conformation of the binding motif is virtually unchanged in the presence or absence of nucleotides.

PubMed: 11953435
DOI: 10.1074/jbc.M202251200

Experimental method

X-RAY DIFFRACTION (1.6 Å)