PDBsum entry 1peh

Nucleotidyltransferase

PDB id: 1peh

Contents

Protein chain

35 a.a. *

* Residue conservation analysis

PDB id:

1peh

Name:

Nucleotidyltransferase

Title:

Nmr structure of the membrane-binding domain of ctp phosphocholine cytidylyltransferase, 10 structures

Structure:

Pepnh1. Chain: a. Fragment: residues 236 - 268. Synonym: cytidylyltransferase membrane binding domain peptide. Engineered: yes. Mutation: yes

Source:

Synthetic: yes. Rattus norvegicus. Norway rat. Organism_taxid: 10116

NMR struc:

10 models

Authors:

S.J.Dunne,R.B.Cornell,J.E.Johnson,N.R.Glover,A.S.Tracey

Key ref:

S.J.Dunne et al. (1996). Structure of the membrane binding domain of CTP:phosphocholine cytidylyltransferase. Biochemistry, 35, 11975-11984. PubMed id: 8810902 DOI: 10.1021/bi960821+

Date:

10-Jun-96 Release date: 07-Dec-96

Protein chain

P19836  (PCY1A_RAT) -  Choline-phosphate cytidylyltransferase A from Rattus norvegicus

Seq: 367 a.a.

Struc: 34 a.a.*

* PDB and UniProt seqs differ at 2 residue positions (black crosses)

Enzyme reactions

• Enzyme class: E.C.2.7.7.15 - choline-phosphate cytidylyltransferase.
• Reaction: phosphocholine + CTP + H⁺ = CDP-choline + diphosphate

Molecule diagrams generated from .mol files obtained from the KEGG ftp site

reference

DOI no: 10.1021/bi960821+

Biochemistry 35:11975-11984 (1996)

PubMed id: 8810902

Structure of the membrane binding domain of CTP:phosphocholine cytidylyltransferase.

S.J.Dunne, R.B.Cornell, J.E.Johnson, N.R.Glover, A.S.Tracey.

ABSTRACT

It has been proposed that the domain of the regulatory enzyme, CTP:phosphocholine cytidylyltransferase, which mediates reversible binding of the enzyme to membranes, is an amphipathic alpha-helix of approximately 60 amino acid residues and that this domain is adjacent to the putative active site domain of this enzyme. Circular dichroism indicated that the secondary structures of two overlapping peptides spanning this region were predominantly alpha-helical in the presence of PG vesicles or sodium dodecyl sulfate micelles. Interproton distances were obtained from two-dimensional NMR spectroscopic measurements to solve the structures of these two peptides. The C-terminal 22 amino acid peptide segment (corresponding to Val267-Ser288) was a well-defined alpha-helix over its length. The N-terminal 33-mer (corresponding to Asn236-Glu268) was composed of an alpha-helix from Glu243 to Lys266, a well-structured bend of about 50 degrees at Tyr240-His241-Leu242, and an N-terminal four-residue helix. It is proposed that the three residues involved in generating the bend act as the hinge between the catalytic and regulatory domains. The nonpolar faces of the 33-mer and 22-mer were interrupted by Ser260, Ser271, and Ser282. These residues may serve to limit the hydrophobicity and facilitate reversible and lipid-selective membrane binding. The hydrophobic faces of the helices were flanked by a set of basic amino acid residues on one side and basic amino acid residues interspersed with glutamates on the other. The disposition of these side chains gives clues to the basis for the specificities of these peptides for anionic surfaces.