PDBsum entry 1ilo

Structural genomics

PDB id: 1ilo

Contents

Protein chain

77 a.a. *

* Residue conservation analysis

PDB id:

1ilo

Name:

Structural genomics

Title:

Nmr structure of a thioredoxin, mth895, from the archeon methanobacterium thermoautotrophicum strain delta h.

Structure:

Conserved hypothetical protein mth895. Chain: a. Engineered: yes

Source:

Methanothermobacter thermautotrophicus str. Delta h. Organism_taxid: 187420. Strain: delta h. Gene: mth895. Expressed in: escherichia coli bl21(de3). Expression_system_taxid: 469008.

NMR struc:

21 models

Authors:

S.Bhattacharyya,B.Habibi-Nazhad,C.M.Slupsky,B.D.Sykes,D.S.Wishart, Northeast Structural Genomics Consortium (Nesg)

Key ref:

S.Bhattacharyya et al. (2002). Identification of a novel archaebacterial thioredoxin: determination of function through structure. Biochemistry, 41, 4760-4770. PubMed id: 11939770 DOI: 10.1021/bi0115176

Date:

08-May-01 Release date: 14-Nov-01

Protein chain

O26981  (THIRX_METTH) -  Thioredoxin from Methanothermobacter thermautotrophicus (strain ATCC 29096 / DSM 1053 / JCM 10044 / NBRC 100330 / Delta H)

Seq: 77 a.a.

Struc: 77 a.a.

Enzyme reactions

• Enzyme class: E.C.1.8.4.8 - phosphoadenylyl-sulfate reductase (thioredoxin).
• Reaction: [thioredoxin]-disulfide + sulfite + adenosine 3',5'-bisphosphate + 2 H⁺ = [thioredoxin]-dithiol + 3'-phosphoadenylyl sulfate

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

reference

DOI no: 10.1021/bi0115176

Biochemistry 41:4760-4770 (2002)

PubMed id: 11939770

Identification of a novel archaebacterial thioredoxin: determination of function through structure.

S.Bhattacharyya, B.Habibi-Nazhad, G.Amegbey, C.M.Slupsky, A.Yee, C.Arrowsmith, D.S.Wishart.

ABSTRACT

As part of a high-throughput, structural proteomic project we have used NMR spectroscopy to determine the solution structure and ascertain the function of a previously unknown, conserved protein (MtH895) from the thermophilic archeon Methanobacterium thermoautotrophicum. Our findings indicate that MtH895 contains a central four-stranded beta-sheet core surrounded by two helices on one side and a third on the other. It has an overall fold superficially similar to that of a glutaredoxin. However, detailed analysis of its three-dimensional structure along with molecular docking simulations of its interaction with T7 DNA polymerase (a thioredoxin-specific substrate) and comparisons with other known members of the thioredoxin/glutaredoxin family of proteins strongly suggest that MtH895 is more akin to a thioredoxin. Furthermore, measurement of the pK(a) values of its active site thiols along with direct measurements of the thioredoxin/glutaredoxin activity has confirmed that MtH895 is, indeed, a thioredoxin and exhibits no glutaredoxin activity. We have also identified a group of previously unknown proteins from several other archaebacteria that have significant (34-44%) sequence identity with MtH895. These proteins have unusual active site -CXXC- motifs not found in any known thioredoxin or glutaredoxin. On the basis of the results presented here, we predict that these small proteins are all members of a new class of truncated thioredoxins.