View source for PE/PPE Protein Complex

<StructureSection load="2g38" size="400" color="" frame="true"  spin="on" Scene='2g38/Pe_ppe_longitudinal/1'  side="right" caption="[[2g38]]" >

[[Image:2g38.png|left|200px]]<br />
   
===A PE/PPE Protein Complex from Mycobacterium tuberculosis===
The heterodimeric <scene name='2g38/Pe_ppe_longitudinal/1'>PE/PPE protein complex</scene> from ''M. tuberculosis'' is composed of a 99 amino acid <scene name='2g38/Pe_ppe_pe/3'>PE protein</scene> protein (Rv2431c, shown in RED) and a 194 amino acid <scene name='2g38/Pe_ppe_ppe/1'>PPE protein</scene> (Rv2430c, shown in BLUE), that are encoded next to each other on the M. tuberculosis genome (suggestive of a potential operon).  These proteins represent two of the largest protein families in the M. tuberculosis genome.  The PE and PPE proteins form an <scene name='2g38/Pe_ppe_longitudinal/1'>elongated helical structure</scene>, reminiscent of a four-helix bundle, which can be best viewed down the <scene name='2g38/Pe_ppe_axis/2'>axis</scene>.  The protein interaction <scene name='2g38/Pe_ppe_interface/1'>interface</scene> between the two proteins is lined with hydrophobic residues, contributing to the stability of the protein complex.  Click here to view a <scene name='2g38/Pe_ppe_space_fill/2'>SpaceFill</scene> representation.

{{ABSTRACT_PUBMED_16690741}}





==About this Structure==
2G38 is a [[Protein complex]] structure of sequences from [http://en.wikipedia.org/wiki/Mycobacterium_tuberculosis_h37rv Mycobacterium tuberculosis h37rv]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2G38 OCA]. 

[[Image:Strong_PNAS_PE_PPE_1.jpg | 400 px]]

Above depicts the crystal structure of the M.tb. PE/PPE protein complex (Adapted from Strong ''et al''. ''PNAS'' 103: 8060–8065 ). (a) Surface representation of the PE/PPE protein complex. The PE protein Rv2431c is shown in red, and the PPE protein Rv2430c is in blue. (b) The PE/PPE protein complex viewed down its longitudinal axis. (c) Ribbon diagram of the PE/PPE protein complex. The complex is composed of seven α-helices. Two α-helices of the PE protein interact with two helices of the PPE protein to form a four-helix bundle. Regions of high sequence conservation are indicated by arrows and discussed in the text. (d) Interface hydrophobicity of the PPE and PE proteins. The hydrophobicity of the interaction interface between the PPE and PE protein is color-coded: the most apolar regions are indicated in red, orange, and yellow, and the most polar regions are indicated in blue. Notice the extensive apolar regions that are shielded from solvent as the complex forms.  (Text and Figure adapted from Strong ''et al''. ''Proc Natl Acad Sci U S A.''  103: 8060–8065 (2006), Figure 3). 

[[Image:Strong_PNAS_PE_PPE_2.jpg | 400 px]]

Interaction interface of the PE/PPE protein complex. (a) Two helices of the PE protein, α1 and α2, interact with two helices of the PPE protein, α2 and α3, to form a four-helix bundle. The four-helix-bundle is largely stabilized by hydrophobic interactions among apolar side chains, as seen in the core of the complex. In contrast, the outer surface is coated with polar residues. (b) The PE/PPE complex as viewed down the longitudinal axis (Text and Figure adapted from Strong ''et al''. ''Proc Natl Acad Sci U S A.''  103: 8060–8065 (2006), Figure 4).

</StructureSection>
   


==Reference==
Toward the structural genomics of complexes: crystal structure of a PE/PPE protein complex from Mycobacterium tuberculosis., Strong M, Sawaya MR, Wang S, Phillips M, Cascio D, Eisenberg D, Proc Natl Acad Sci U S A. 2006 May 23;103(21):8060-5. Epub 2006 May 11. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/16690741 16690741]
[[Category:Topic Page]]
[[Category: Mycobacterium tuberculosis h37rv]]
[[Category: Protein complex]]
[[Category: Eisenberg, D.]]
[[Category: Sawaya, M R.]]
[[Category: Strong, M.]]
[[Category: TBSGC, TB Structural Genomics Consortium.]]
[[Category: Protein structure initiative]]
[[Category: Protein-protein complex]]
[[Category: Psi]]
[[Category: Structural genomic]]
[[Category: Tb structural genomics consortium]]
[[Category: Tbsgc]]
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*Created with the participation of [[User:Michael Strong|Michael Strong]], [[User:Eran Hodis|Eran Hodis]].