The crystal structure of lipase II from Rhizopus niveus at 2.2 A resolution.
The crystal and molecular structure of Lipase II from Rhizopus niveus was analyzed using X-ray single crystal diffraction data at a resolution of 2.2 A. The structure was refined to an R-factor of 0.19 for all available data. This lipase was purified and crystallized as Lipase I, which contains two polypeptide chains combined through non-covalent interaction. However, during crystal growth, Lipase I was converted to Lipase II, which consists of a single polypeptide chain of 269 amino acid residues, by limited proteolysis. The structure of Lipase II shows a typical alpha/beta hydrolase fold containing the so-called nucleophilic elbow. The catalytic center of this enzyme is analogous to those of other neutral lipases and serine proteases. This catalytic center is sheltered by an alpha-helix lid, which appears in neutral lipases, opening the active site at the oil-water interface.
Central Research Institute Tsukuba R&D Center, Fuji Oil Co., Ltd., Ibaraki. kouno@fujioil.co.jp
M
M
Kohno
J
J
Funatsu
B
B
Mikami
W
W
Kugimiya
T
T
Matsuo
Y
Y
Morita
D000595:Amino Acid Sequence; D018360:Crystallography, X-Ray; D005656:Fungal Proteins; D008049:Lipase / Q000737:chemistry* / Q000302:isolation & purification; D046911:Macromolecular Substances; D008958:Models, Molecular; D008961:Models, Structural; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D012233:Rhizopus / Q000201:enzymology*
D005656:Fungal Proteins; D046911:Macromolecular Substances; D008049:Lipase; C104055:lipase II