PDBsum entry 1a8c

Hemoprotein

PDB id: 1a8c

Contents

Protein chain

81 a.a. *

Ligands

HEC

* Residue conservation analysis

PDB id:

1a8c

Name:

Hemoprotein

Title:

Primary sequence and solution conformation of ferrocytochromE C-552 from nitrosomonas europaea, nmr, mean structure refined without hydrogen bond constraints

Structure:

FerrocytochromE C-552. Chain: a. Synonym: c-551

Source:

Nitrosomonas europaea. Organism_taxid: 915

NMR struc:

1 models

Authors:

R.Timkovich,D.Bergmann,D.M.Arciero,A.B.Hooper

Key ref:

R.Timkovich et al. (1998). Primary sequence and solution conformation of ferrocytochrome c-552 from Nitrosomonas europaea. Biophys J, 75, 1964-1972. PubMed id: 9746537

Date:

23-Mar-98 Release date: 21-Oct-98

Protein chain

P95339  (CY552_NITEU) -  Cytochrome c-552 from Nitrosomonas europaea (strain ATCC 19718 / CIP 103999 / KCTC 2705 / NBRC 14298)

Seq: 103 a.a.

Struc: 81 a.a.

Biophys J 75:1964-1972 (1998)

PubMed id: 9746537

Primary sequence and solution conformation of ferrocytochrome c-552 from Nitrosomonas europaea.

R.Timkovich, D.Bergmann, D.M.Arciero, A.B.Hooper.

ABSTRACT

Cytochrome c-552 from Nitrosomonas europaea is a 9.1-kDa monoheme protein that is a member of the bacterial cytochrome c-551 family. The gene encoding for c-552 has been cloned and sequenced and the primary sequence of the product deduced. Proton resonance assignments were made for all main-chain and most side-chain protons in the diamagnetic, reduced form by two-dimensional NMR techniques. Distance constraints (1056) were determined from nuclear Overhauser enhancements, and torsion angle constraints (88) were determined from scalar coupling estimates. Solution conformations for the protein were computed by the hybrid distance geometry-simulated annealing approach. For 20 computed structures, the root mean squared deviation from the average position of equivalent atoms was 0.84 A (sigma = 0.12) for backbone atoms over all residues. Analysis by residue revealed there were three regions clearly less well defined than the rest of the protein: the first two residues at the N-terminus, the last two at the C-terminus, and a loop region from residues 34 to 40. Omitting these regions from the comparison, the root mean squared deviation was 0.61 A (sigma = 0.13) for backbone atoms, 0.86 A (sigma = 0.12) for all associated heavy atoms, and 0. 43 A (sigma = 0.17) for the heme group. The global folding of the protein is consistent with others in the c-551 family. A deletion at the N-terminus relative to other family members had no impact on the global folding, whereas an insertion at residue 65 did affect the way the polypeptide packs against the methionine-ligated side of the heme. The effects of specific substitutions will be discussed. The structure of c-552 serves to delineate essential features of the c-551 family.