Structural highlights
Function
[A85C_MYCTU] The antigen 85 proteins (FbpA, FbpB, FbpC) are responsible for the high affinity of mycobacteria to fibronectin, a large adhesive glycoprotein, which facilitates the attachment of M.tuberculosis to murine alveolar macrophages (AMs). They also help to maintain the integrity of the cell wall by catalyzing the transfer of mycolic acids to cell wall arabinogalactan and through the synthesis of alpha,alpha-trehalose dimycolate (TDM, cord factor). They catalyze the transfer of a mycoloyl residue from one molecule of alpha,alpha-trehalose monomycolate (TMM) to another TMM, leading to the formation of TDM.[1] [2]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
The antigen 85 (ag85) complex, composed of three proteins (ag85A, B and C), is a major protein component of the Mycobacterium tuberculosis cell wall. Each protein possesses a mycolyltransferase activity required for the biogenesis of trehalose dimycolate (cord factor), a dominant structure necessary for maintaining cell wall integrity. The crystal structure of recombinant ag85C from M. tuberculosis, refined to a resolution of 1.5 A, reveals an alpha/beta-hydrolase polypeptide fold, and a catalytic triad formed by Ser 124, Glu 228 and His 260. ag85C complexed with a covalent inhibitor implicates residues Leu 40 and Met 125 as components of the oxyanion hole. A hydrophobic pocket and tunnel extending 21 A into the core of the protein indicates the location of a probable trehalose monomycolate binding site. Also, a large region of conserved surface residues among ag85A, B and C is a probable site for the interaction of ag85 proteins with human fibronectin.
Crystal structure of the secreted form of antigen 85C reveals potential targets for mycobacterial drugs and vaccines.,Ronning DR, Klabunde T, Besra GS, Vissa VD, Belisle JT, Sacchettini JC Nat Struct Biol. 2000 Feb;7(2):141-6. PMID:10655617[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Abou-Zeid C, Garbe T, Lathigra R, Wiker HG, Harboe M, Rook GA, Young DB. Genetic and immunological analysis of Mycobacterium tuberculosis fibronectin-binding proteins. Infect Immun. 1991 Aug;59(8):2712-8. PMID:1830294
- ↑ Belisle JT, Vissa VD, Sievert T, Takayama K, Brennan PJ, Besra GS. Role of the major antigen of Mycobacterium tuberculosis in cell wall biogenesis. Science. 1997 May 30;276(5317):1420-2. PMID:9162010
- ↑ Ronning DR, Klabunde T, Besra GS, Vissa VD, Belisle JT, Sacchettini JC. Crystal structure of the secreted form of antigen 85C reveals potential targets for mycobacterial drugs and vaccines. Nat Struct Biol. 2000 Feb;7(2):141-6. PMID:10655617 doi:10.1038/72413
