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X-ray structure analysis and characterization of AFUEI, an elastase inhibitor from Aspergillus fumigatus.

ABSTRACT: Elastase from Aspergillus sp. is an important factor for aspergillosis. AFUEI is an inhibitor of the elastase derived from Aspergillus fumigatus. AFUEI is a member of the I78 inhibitor family and has a high inhibitory activity against elastases of Aspergillus fumigatus and Aspergillus flavus, human neutrophil elastase and bovine chymotrypsin, but does not inhibit bovine trypsin. Here we report the crystal structure of AFUEI in two crystal forms. AFUEI is a wedge-shaped protein composed of an extended loop and a scaffold protein core. The structure of AFUEI shows remarkable similarity to serine protease inhibitors of the potato inhibitor I family, although they are classified into different inhibitor families. A structural comparison with the potato I family inhibitors suggests that the extended loop of AFUEI corresponds to the binding loop of the potato inhibitor I family, and AFUEI inhibits its cognate proteases through the same mechanism as the potato I family inhibitors.

SUBMITTER: Sakuma M

PROVIDER: S-EPMC3682545 | biostudies-literature | 2013 Jun

REPOSITORIES: biostudies-literature

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X-ray structure analysis and characterization of AFUEI, an elastase inhibitor from Aspergillus fumigatus.

Sakuma Mayuko M Imada Katsumi K Okumura Yoshiyuki Y Uchiya Kei-ichi K Yamashita Nobuo N Ogawa Kenji K Hijikata Atsushi A Shirai Tsuyoshi T Homma Michio M Nikai Toshiaki T

The Journal of biological chemistry 20130502 24

Elastase from Aspergillus sp. is an important factor for aspergillosis. AFUEI is an inhibitor of the elastase derived from Aspergillus fumigatus. AFUEI is a member of the I78 inhibitor family and has a high inhibitory activity against elastases of Aspergillus fumigatus and Aspergillus flavus, human neutrophil elastase and bovine chymotrypsin, but does not inhibit bovine trypsin. Here we report the crystal structure of AFUEI in two crystal forms. AFUEI is a wedge-shaped protein composed of an ext ...[more]

PMID: 23640894

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Dataset Information

X-ray structure analysis and characterization of AFUEI, an elastase inhibitor from Aspergillus fumigatus.

Publications

X-ray structure analysis and characterization of AFUEI, an elastase inhibitor from Aspergillus fumigatus.

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