1FB6

CRYSTAL STRUCTURE OF THIOREDOXIN M FROM SPINACH CHLOROPLAST (OXIDIZED FORM)

PDB DOI: 10.2210/pdb1FB6/pdb

Classification: ELECTRON TRANSPORT
Organism(s): Spinacia oleracea
Expression System: Escherichia coli
Mutation(s): No

Deposited: 2000-07-14 Released: 2000-09-20
Deposition Author(s): Capitani, G., Markovic-Housley, Z., DelVal, G., Morris, M., Jansonius, J.N., Schurmann, P.

Experimental Data Snapshot

Method: X-RAY DIFFRACTION
Resolution: 2.10 Å
R-Value Free: 0.230
R-Value Work: 0.204

wwPDB Validation 3D Report Full Report

This is version 1.2 of the entry. See complete history.

Literature

Crystal structures of two functionally different thioredoxins in spinach chloroplasts.

Capitani, G., Markovic-Housley, Z., DelVal, G., Morris, M., Jansonius, J.N., Schurmann, P.

(2000) J Mol Biol 302: 135-154

PubMed: 10964566 Search on PubMed
DOI: 10.1006/jmbi.2000.4006
Primary Citation of Related Structures:
1F9M, 1FAA, 1FB0, 1FB6

PubMed Abstract:

Thioredoxins are small ubiquitous proteins which act as general protein disulfide reductases in living cells. Chloroplasts contain two distinct thioredoxins ( f and m) with different phylogenetic origin. Both act as enzyme regulatory proteins but have different specificities towards target enzymes. Thioredoxin f (Trx f), which shares only low sequence identity with thioredoxin m (Trx m) and with all other known thioredoxins, activates enzymes of the Calvin cycle and other photosynthetic processes. Trx m shows high sequence similarity with bacterial thioredoxins and activates other chloroplast enzymes. The here described structural studies of the two chloroplast thioredoxins were carried out in order to gain insight into the structure/function relationships of these proteins. Crystal structures were determined for oxidized, recombinant thioredoxin f (Trx f-L) and at the N terminus truncated form of it (Trx f-S), as well as for oxidized and reduced thioredoxin m (at 2.1 and 2.3 A resolution, respectively). Whereas thioredoxin f crystallized as a monomer, both truncated thioredoxin f and thioredoxin m crystallized as non-covalent dimers. The structures of thioredoxins f and m exhibit the typical thioredoxin fold consisting of a central twisted five-stranded beta-sheet surrounded by four alpha-helices. Thioredoxin f contains an additional alpha-helix at the N terminus and an exposed third cysteine close to the active site. The overall three-dimensional structures of the two chloroplast thioredoxins are quite similar. However, the two proteins have a significantly different surface topology and charge distribution around the active site. An interesting feature which might significantly contribute to the specificity of thioredoxin f is an inherent flexibility of its active site, which has expressed itself crystallographically in two different crystal forms.

Organizational Affiliation:

Structural Biology Division Biozentrum, University of Basel, Basel, CH-4056, Switzerland. capitani@biocfebs.unizh.ch

Macromolecules

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(by identity cutoff) | 3D Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
THIOREDOXIN M	A, B	105	Spinacia oleracea	Mutation(s): 0
UniProt
Find proteins for P07591 (Spinacia oleracea) Explore P07591 Go to UniProtKB: P07591
Entity Groups
Sequence Clusters	30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt Group	P07591
Protein Feature View Expand
Reference Sequence