3WZ1: Catalytic Domain Of Beta-agarase From Microbulbifer Thermotolerans Jamb-a94

A deep-sea bacterium, Microbulbifer thermotolerans JAMB-A94, has a beta-agarase (MtAgaA) belonging to the glycoside hydrolase family (GH) 16. The optimal temperature of this bacterium for growth is 43-49 degrees C, and MtAgaA is stable at 60 degrees C, which is one of the most thermostable enzymes among GH16 beta-agarases. Here, we determined the catalytic domain structure of MtAgaA. MtAgaA consists of a beta-jelly roll fold, as observed in other GH16 enzymes. The structure of MtAgaA was most similar to two beta-agarases from Zobellia galactanivorans, ZgAgaA, and ZgAgaB. Although the catalytic cleft structure of MtAgaA was similar to ZgAgaA and ZgAgaB, residues at subsite -4 of MtAgaA were not conserved between them. Also, an alpha-helix, designated as alpha4', was uniquely located near the catalytic cleft of MtAgaA. A comparison of the structures of the three enzymes suggested that multiple factors, including increased numbers of arginine and proline residues, could contribute to the thermostability of MtAgaA.
PDB ID: 3WZ1Download
MMDB ID: 124813
PDB Deposition Date: 2014/9/12
Updated in MMDB: 2014/11
Experimental Method:
x-ray diffraction
Resolution: 1.6  Å
Source Organism:
Similar Structures:
Biological Unit for 3WZ1: monomeric; determined by author and by software (PISA)
Molecular Components in 3WZ1
Label Count Molecule
Protein (1 molecule)
Molecule annotation
Chemicals (4 molecules)
* Click molecule labels to explore molecular sequence information.

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