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Structural and biochemical analysis of a thermostable membrane-bound stomatin-specific protease.

ABSTRACT: Membrane-bound proteases are involved in various regulatory functions. The N-terminal region of PH1510p (1510-N) from the hyperthermophilic archaeon Pyrococcus horikoshii is a serine protease with a catalytic Ser-Lys dyad (Ser97 and Lys138), and specifically cleaves the C-terminal hydrophobic region of the p-stomatin PH1511p. In a form of human hemolytic anemia known as hereditary stomatocytosis, the stomatin protein is deficient in the erythrocyte membrane due to mis-trafficking. In order to understand the catalytic mechanism of 1510-N in more detail, here the structural and biochemical analysis of 1510-N is reported. Two degraded products were produced via acyl-enzyme intermediates. 1510-N is a thermostable protease, and thus crystallization after heat treatment of the protease-peptide complex was attempted in order to understand the catalytic mechanism of 1510-N. The structure after heat treatment is almost identical to that with no heat treatment. According to the superposition between the structures with heat treatment and with no heat treatment, the N-terminal half of the peptide is superposed well, whereas the C-terminal half of the peptide is slightly deviated. The N-terminal half of the peptide binds to 1510-N more tightly than the C-terminal half of the peptide. The flexible L2 loops of 1510-N cover the peptide, and are involved in the protease activity.

SUBMITTER: Yokoyama H

PROVIDER: S-EPMC3795559 | biostudies-literature | 2013 Nov

REPOSITORIES: biostudies-literature

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Structural and biochemical analysis of a thermostable membrane-bound stomatin-specific protease.

Yokoyama Hideshi H Kobayashi Daisuke D Takizawa Naoto N Fujii Satoshi S Matsui Ikuo I

Journal of synchrotron radiation 20130925 Pt 6

Membrane-bound proteases are involved in various regulatory functions. The N-terminal region of PH1510p (1510-N) from the hyperthermophilic archaeon Pyrococcus horikoshii is a serine protease with a catalytic Ser-Lys dyad (Ser97 and Lys138), and specifically cleaves the C-terminal hydrophobic region of the p-stomatin PH1511p. In a form of human hemolytic anemia known as hereditary stomatocytosis, the stomatin protein is deficient in the erythrocyte membrane due to mis-trafficking. In order to un ...[more]

PMID: 24121343

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Dataset Information

Structural and biochemical analysis of a thermostable membrane-bound stomatin-specific protease.

Publications

Structural and biochemical analysis of a thermostable membrane-bound stomatin-specific protease.

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