1YG9

The structure of mutant (N93Q) of bla g 2

Summary for 1YG9

• Entry DOI: 10.2210/pdb1yg9/pdb
• Descriptor: Aspartic protease Bla g 2, 2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose, 2-acetamido-2-deoxy-beta-D-glucopyranose, ... (5 entities in total)
• Functional Keywords: bla g 2, allegren, hydrolase, allergen
• Biological source: Blattella germanica (German cockroach)
• Total number of polymer chains: 1
• Total formula weight: 36894.76

Authors

Li, M.,Gustchina, A.,Wuenschmann, S.,Pomes, A.,Wlodawer, A. (deposition date: 2005-01-04, release date: 2005-03-22, Last modification date: 2021-10-20)

Primary citation

Gustchina, A.,Li, M.,Wuenschmann, S.,Chapman, M.D.,Pomes, A.,Wlodawer, A.
Crystal structure of cockroach allergen Bla g 2, an unusual zinc binding aspartic protease with a novel mode of self-inhibition.
J.Mol.Biol., 348:433-444, 2005

PubMed Abstract: The crystal structure of Bla g 2 was solved in order to investigate the structural basis for the allergenic properties of this unusual protein. This is the first structure of an aspartic protease in which conserved glycine residues, in two canonical DTG triads, are substituted by different amino acid residues. Another unprecedented feature revealed by the structure is the single phenylalanine residue insertion on the tip of the flap, with the side-chain occupying the S1 binding pocket. This and other important amino acid substitutions in the active site region of Bla g 2 modify the interactions in the vicinity of the catalytic aspartate residues, increasing the distance between them to approximately 4A and establishing unique direct contacts between the flap and the catalytic residues. We attribute the absence of substantial catalytic activity in Bla g 2 to these unusual features of the active site. Five disulfide bridges and a Zn-binding site confer stability to the protein, which may contribute to sensitization at lower levels of exposure than other allergens.

PubMed: 15811379
DOI: 10.1016/j.jmb.2005.02.062

Experimental method

X-RAY DIFFRACTION (1.3 Å)