3mvt

Crystal structure of apo mADA at 2.2A resolution

spinqualitylabelsall models 3mvt, resolution 2.20Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 3mvt is a 2 chain structure with sequence from Mus musculus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Ligands: CL, GOL Related: 1a4m, 3mvi Gene: Ada (Mus musculus) Activity: Adenosine deaminase, with EC number 3.5.4.4 Resources: FirstGlance, OCA, RCSB, PDBsum Function [ADA_MOUSE] Catalyzes the hydrolytic deamination of adenosine and 2-deoxyadenosine. Plays an important role in purine metabolism and in adenosine homeostasis. Modulates signaling by extracellular adenosine, and so contributes indirectly to cellular signaling events. Acts as a positive regulator of T-cell coactivation, by binding DPP4. Its interaction with DPP4 regulates lymphocyte-epithelial cell adhesion (By similarity). Publication Abstract from PubMed Adenosine deaminase (ADA) is a key enzyme in purine metabolism and crucial for normal immune competence. It is a 40 kDa monomeric TIM-barrel protein containing a tightly bound Zn(2+), which is required for activity. In this study, we have investigated the role of Zn(2+) with respect to ADA structure and stability. After removing Zn(2+), the crystallographic structure of the protein remains highly ordered and similar to that of the holo protein with structural changes limited to regions capping the active site pocket. The stability of the protein, however, is decreased significantly in the absence of Zn(2+). Denaturation with urea shows the midpoint to be about 3.5 M for the apo enzyme, compared with 6.4 M for the holo enzyme. ADA contains four tryptophan residues distant from the Zn(2+)site. (19)F NMR studies in the presence and absence of Zn(2+) were carried out after incorporation of 6-(19)F-tryptophan. Chemical shift differences were observed for three of the four tryptophan residues, suggesting that, in contrast to the X-ray data, Zn(2+)-induced structural changes are propagated throughout the protein. Changes throughout the structure as suggested by the NMR data may explain the lower stability of the Zn(2+)-free protein. Real-time (19)F NMR spectroscopy measuring the loss of Zn(2+) showed that structural changes correlated with the loss of enzymatic activity. The Role of Zn(2+) on the Structure and Stability of Murine Adenosine Deaminase (dagger).,Niu W, Shu Q, Chen Z, Mathews S, Di Cera E, Frieden C J Phys Chem B. 2010 Sep 3. PMID:20815357 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Adenosine deaminase

Proteopedia Page Contributors and Editors (what is this?)

OCA