4TOQ

Crystal structure of class III chitinase from pomegranate provides the insight into its metal storage capacity

Summary for 4TOQ

• Entry DOI: 10.2210/pdb4toq/pdb
• Descriptor: Class III chitinase, MAGNESIUM ION, CHLORIDE ION, ... (4 entities in total)
• Functional Keywords: chitinase, metal binding, a, b-barrel, pomegranate seed, hydrolase
• Biological source: Punica granatum (Pomegranate)
• Total number of polymer chains: 4
• Total formula weight: 116628.86

Authors

Masuda, T.,Zhao, G.,Mikami, B. (deposition date: 2014-06-06, release date: 2014-09-10, Last modification date: 2024-11-20)

Primary citation

Masuda, T.,Zhao, G.,Mikami, B.
Crystal structure of class III chitinase from pomegranate provides the insight into its metal storage capacity.
Biosci.Biotechnol.Biochem., 79:45-50, 2015

PubMed Abstract: Chitinase hydrolyzes the β-1,4-glycosidic bond in chitin. In higher plants, this enzyme has been regarded as a pathogenesis-related protein. Recently, we identified a class III chitinase, which functions as a calcium storage protein in pomegranate (Punica granatum) seed (PSC, pomegranate seed chitinase). Here, we solved a crystal structure of PSC at 1.6 Å resolution. Although its overall structure, including the structure of catalytic site and non-proline cis-peptides, was closely similar to those of other class III chitinases, PSC had some unique structural characteristics. First, there were some metal-binding sites with coordinated water molecules on the surface of PSC. Second, many unconserved aspartate residues were present in the PSC sequence which rendered the surface of PSC negatively charged. This acidic electrostatic property is in contrast to that of hevamine, well-characterized plant class III chitinase, which has rather a positively charged surface. Thus, the crystal structure provides a clue for metal association property of PSC.

PubMed: 25252615
DOI: 10.1080/09168451.2014.962475

Experimental method

X-RAY DIFFRACTION (1.6 Å)