spacer
spacer

PDBsum entry 2fxt

Go to PDB code: 
protein links
Protein transport PDB id
2fxt
Jmol
Contents
Protein chain
192 a.a. *
* Residue conservation analysis
PDB id:
2fxt
Name: Protein transport
Title: Crystal structure of yeast tim44
Structure: Import inner membrane translocase subunit tim44. Chain: a. Fragment: c- terminal domain, residues 245-425. Synonym: mitochondrial protein import protein 1. Engineered: yes
Source: Saccharomyces cerevisiae. Baker's yeast. Organism_taxid: 4932. Gene: tim44. Expressed in: escherichia coli bl21. Expression_system_taxid: 511693.
Resolution:
3.20Å     R-factor:   0.316     R-free:   0.368
Authors: R.Josyula,B.Sha
Key ref:
R.Josyula et al. (2006). Crystal structure of yeast mitochondrial peripheral membrane protein Tim44p C-terminal domain. J Mol Biol, 359, 798-804. PubMed id: 16647716 DOI: 10.1016/j.jmb.2006.04.020
Date:
06-Feb-06     Release date:   06-Feb-07    
PROCHECK
Go to PROCHECK summary
 Headers
 References

Protein chain
Pfam   ArchSchema ?
Q01852  (TIM44_YEAST) -  Mitochondrial import inner membrane translocase subunit TIM44
Seq:
Struc:
431 a.a.
192 a.a.
Key:    PfamA domain  PfamB domain  Secondary structure  CATH domain

 

 
DOI no: 10.1016/j.jmb.2006.04.020 J Mol Biol 359:798-804 (2006)
PubMed id: 16647716  
 
 
Crystal structure of yeast mitochondrial peripheral membrane protein Tim44p C-terminal domain.
R.Josyula, Z.Jin, Z.Fu, B.Sha.
 
  ABSTRACT  
 
The protein transports from the cell cytosol to the mitochondria matrix are carried out by the translocase of the outer membrane (TOM) complex and the translocase of the inner membrane (TIM) complexes. Tim44p is an essential mitochondrial peripheral membrane protein and a major component of TIM23 translocon. Tim44p can tightly associate with the inner mitochondrial membrane. To investigate the mechanism by which Tim44p functions in the TIM23 translocon to deliver the mitochondrial protein precursors, we have determined the crystal structure of the yeast Tim44p C-terminal domain to 3.2A resolution using the MAD method. The Tim44p C-terminal domain forms a monomer in the crystal structure and contains six alpha-helices and four antiparallel beta-strands. A large hydrophobic pocket was identified on the Tim44p structure surface. The N-terminal helix A1 is positively charged and the helix A1 protrudes out from the Tim44p main body.
 
  Selected figure(s)  
 
Figure 2.
Figure 2. The large hydrophobic pocket on Tim44p surface. (a) Surface potential drawing of the Tim44p monomer molecule determined by GRASP.^21 The Tim44p is in the similar orientation as Figure 1(a). Blue and red denote positively and negatively charged regions, respectively. White indicates hydrophobic region. The scale bar of the surface potential is shown in the top of the Figure. The hydrophobic pocket is drawn in a red box. (b) The magnified version of the area within the red box in (a). The hydrophobic residues that are involved in forming the hydrophobic pocket are labeled. Figure 2. The large hydrophobic pocket on Tim44p surface. (a) Surface potential drawing of the Tim44p monomer molecule determined by GRASP.[4]^21 The Tim44p is in the similar orientation as [5]Figure 1(a). Blue and red denote positively and negatively charged regions, respectively. White indicates hydrophobic region. The scale bar of the surface potential is shown in the top of the Figure. The hydrophobic pocket is drawn in a red box. (b) The magnified version of the area within the red box in (a). The hydrophobic residues that are involved in forming the hydrophobic pocket are labeled.
Figure 3.
Figure 3. Sequence alignment of the Tim44p C-terminal domain from various species. Program Pileup from GCG package was utilized to align the Tim44p C-terminal domain sequence from S. cerevisiae with that from Homo sapiens, Mus musculus and Caenorhabditis elegans. The amino acid residues of yeast Tim44p are numbered above the alignment. The amino acid residues involved in forming the hydrophobic pocket of Tim44p are shown in bold. The conserved positively charged residues in helix A1 and A2 are underlined.
 
  The above figures are reprinted by permission from Elsevier: J Mol Biol (2006, 359, 798-804) copyright 2006.  
  Figures were selected by an automated process.  

Literature references that cite this PDB file's key reference

  PubMed id Reference
18426906 D.Schiller, Y.C.Cheng, Q.Liu, W.Walter, and E.A.Craig (2008).
Residues of Tim44 involved in both association with the translocon of the inner mitochondrial membrane and regulation of mitochondrial Hsp70 tethering.
  Mol Cell Biol, 28, 4424-4433.  
17825565 M.J.Baker, A.E.Frazier, J.M.Gulbis, and M.T.Ryan (2007).
Mitochondrial protein-import machinery: correlating structure with function.
  Trends Cell Biol, 17, 456-464.  
18084070 N.Handa, S.Kishishita, S.Morita, R.Akasaka, Z.Jin, J.Chrzas, L.Chen, Z.J.Liu, B.C.Wang, S.Sugano, A.Tanaka, T.Terada, M.Shirouzu, and S.Yokoyama (2007).
Structure of the human Tim44 C-terminal domain in complex with pentaethylene glycol: ligand-bound form.
  Acta Crystallogr D Biol Crystallogr, 63, 1225-1234.
PDB code: 2cw9
17881357 O.Slutsky-Leiderman, M.Marom, O.Iosefson, R.Levy, S.Maoz, and A.Azem (2007).
The interplay between components of the mitochondrial protein translocation motor studied using purified components.
  J Biol Chem, 282, 33935-33942.  
17263664 W.Neupert, and J.M.Herrmann (2007).
Translocation of proteins into mitochondria.
  Annu Rev Biochem, 76, 723-749.  
17099692 R.Albrecht, P.Rehling, A.Chacinska, J.Brix, S.A.Cadamuro, R.Volkmer, B.Guiard, N.Pfanner, and K.Zeth (2006).
The Tim21 binding domain connects the preprotein translocases of both mitochondrial membranes.
  EMBO Rep, 7, 1233-1238.
PDB code: 2ciu
The most recent references are shown first. Citation data come partly from CiteXplore and partly from an automated harvesting procedure. Note that this is likely to be only a partial list as not all journals are covered by either method. However, we are continually building up the citation data so more and more references will be included with time. Where a reference describes a PDB structure, the PDB code is shown on the right.