1ymq

HAD Superfamily Phosphotransferase Substrate Diversification: Structure and Function Analysis of the HAD Subclass IIB Sugar Phosphatase BT4131

spinqualitylabelsall models 1ymq, resolution 1.90Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 1ymq is a 1 chain structure with sequence from Bacteroides thetaiotaomicron. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Ligands: MG, SO4 Resources: FirstGlance, OCA, RCSB, PDBsum 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 BT4131 gene from the bacterium Bacteroides thetaiotaomicron VPI-5482 has been cloned and overexpressed in Escherichia coli. The protein, a member of the haloalkanoate dehalogenase superfamily (subfamily IIB), was purified to homogeneity, and its X-ray crystal structure was determined to1.9 A resolution using the molecular replacement phasing method. BT4131 was shown by an extensive substrate screen to be a broad-range sugar phosphate phosphatase. On the basis of substrate specificity and gene context, the physiological function of BT4131 in chitin metabolism has been tentatively assigned. Comparison of the BT4131 structure alpha/beta cap domain structure with those of other type IIB enzymes (phosphoglycolate phosphatase, trehalose-6-phosphate phosphatase, and proteins of unknown function known as PDB entries , , and ) identified two conserved loops (BT4131 residues 172-182 and 118-130) in the alphabetabeta(alphabetaalphabeta)alphabetabeta type caps and one conserved loop in the alphabetabetaalphabetabeta type caps, which contribute residues for contact with the substrate leaving group. In BT4131, the two loops contribute one polar and two nonpolar residues to encase the displaced sugar. This finding is consistent with the lax specificity BT4131 has for the ring size and stereochemistry of the sugar phosphate. In contrast, substrate docking showed that the high-specificity phosphoglycolate phosphatase (PDB entry ) uses a single substrate specificity loop to position three polar residues for interaction with the glycolate leaving group. We show how active site "solvent cages" derived from analysis of the structures of the type IIB HAD phosphatases could be used in conjunction with the identity of the residues stationed along the cap domain substrate specificity loops, as a means of substrate identification. HAD superfamily phosphotransferase substrate diversification: structure and function analysis of HAD subclass IIB sugar phosphatase BT4131.,Lu Z, Dunaway-Mariano D, Allen KN Biochemistry. 2005 Jun 21;44(24):8684-96. PMID:15952775 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

Proteopedia Page Contributors and Editors (what is this?)

OCA