Structural Insights into the -Mannosidase from T. reesei Obtained by Synchrotron Small-Angle X-ray Solution Sc
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- 作者：Ricardo Aparicio ; Hannes Fischer ; David J. Scott ; Koen H. G. Verschueren ; $ ; Anna A. Kulminskaya ; Elena V. Eneiskaya ; Kirill N. Neustroev ; Aldo Felix Craievich ; Alexander M. Golubev ; and Igo
- 刊名：Biochemistry
- 出版年：2002
- 出版时间：July 30, 2002
- 年：2002
- 卷：41
- 期：30
- 页码：9370 - 9375
- 全文大小：354K
- 年卷期：v.41,no.30(July 30, 2002)
- ISSN：1520-4995
文摘
A molecular envelope of the 
-mannosidase from Trichoderma reesei has been obtained bycombined use of solution small-angle X-ray scattering (SAXS) and protein crystallography. Crystallographicdata at 4 Å resolution have been used to enhance informational content of the SAXS data and to obtainan independent, more detailed protein shape. The phased molecular replacement technique using a lowresolution SAXS model, building, and refinement of a free atom model has been employed successfully.The SAXS and crystallographic free atom models exhibit a similar globular form and were used to assessavailable crystallographic models of glycosyl hydrolases. The structure of the -galactosidase, a memberof a family 2, clan GHA glycosyl hydrolases, shows an excellent fit to the experimental molecular envelopeand distance distribution function of the -mannosidase, indicating gross similarities in their three-dimensional structures. The secondary structure of -mannosidase quantified by circular dichroismmeasurements is in a good agreement with that of -galactosidase. We show that a comparison of distancedistribution functions in combination with 1D and 2D sequence alignment techniques was able to restrictthe number of possible structurally homologous proteins. The method could be applied as a general methodin structural genomics and related fields once protein solution scattering data are available.
-mannosidase from Trichoderma reesei has been obtained bycombined use of solution small-angle X-ray scattering (SAXS) and protein crystallography. Crystallographicdata at 4 Å resolution have been used to enhance informational content of the SAXS data and to obtainan independent, more detailed protein shape. The phased molecular replacement technique using a lowresolution SAXS model, building, and refinement of a free atom model has been employed successfully.The SAXS and crystallographic free atom models exhibit a similar globular form and were used to assessavailable crystallographic models of glycosyl hydrolases. The structure of the -galactosidase, a memberof a family 2, clan GHA glycosyl hydrolases, shows an excellent fit to the experimental molecular envelopeand distance distribution function of the -mannosidase, indicating gross similarities in their three-dimensional structures. The secondary structure of -mannosidase quantified by circular dichroismmeasurements is in a good agreement with that of -galactosidase. We show that a comparison of distancedistribution functions in combination with 1D and 2D sequence alignment techniques was able to restrictthe number of possible structurally homologous proteins. The method could be applied as a general methodin structural genomics and related fields once protein solution scattering data are available.