1lto: Difference between revisions
New page: left|200px<br /> <applet load="1lto" size="450" color="white" frame="true" align="right" spinBox="true" caption="1lto, resolution 2.20Å" /> '''Human alpha1-trypta... |
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[[Image:1lto.gif|left|200px]]<br /> | [[Image:1lto.gif|left|200px]]<br /><applet load="1lto" size="350" color="white" frame="true" align="right" spinBox="true" | ||
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caption="1lto, resolution 2.20Å" /> | caption="1lto, resolution 2.20Å" /> | ||
'''Human alpha1-tryptase'''<br /> | '''Human alpha1-tryptase'''<br /> | ||
==Overview== | ==Overview== | ||
Human mast cell tryptases represent a subfamily of trypsin-like serine | Human mast cell tryptases represent a subfamily of trypsin-like serine proteinases implicated in asthma. Unlike beta-tryptases, alpha-tryptases apparently are proteolytically inactive. We have solved the 2.2A crystal structure of mature human alpha1-tryptase. It reveals a frame-like tetrameric architecture that, surprisingly, does not require heparin-binding for stability. In marked contrast to beta2-tryptase, the Ser214-Gly219 segment, which normally provides the template for substrate binding, is kinked in alpha-tryptase, thereby blocking its non-primed subsites. This so far unobserved subsite distortion is incompatible with productive substrate binding and processing. alpha-Tryptase apparently is trapped in this off-conformation by repulsions and attractions of the Asp216 side-chain. However, proteolytic activity could be generated by an induced-fit mechanism. | ||
==About this Structure== | ==About this Structure== | ||
1LTO is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Active as [http://en.wikipedia.org/wiki/Tryptase Tryptase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.4.21.59 3.4.21.59] Full crystallographic information is available from [http:// | 1LTO is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Active as [http://en.wikipedia.org/wiki/Tryptase Tryptase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.4.21.59 3.4.21.59] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1LTO OCA]. | ||
==Reference== | ==Reference== | ||
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[[Category: Huber, R.]] | [[Category: Huber, R.]] | ||
[[Category: Marquardt, U.]] | [[Category: Marquardt, U.]] | ||
[[Category: Sommerhoff, C | [[Category: Sommerhoff, C P.]] | ||
[[Category: Zettl, F.]] | [[Category: Zettl, F.]] | ||
[[Category: hydrolase]] | [[Category: hydrolase]] | ||
''Page seeded by [http:// | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:48:26 2008'' | ||
Revision as of 14:48, 21 February 2008
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Human alpha1-tryptase
OverviewOverview
Human mast cell tryptases represent a subfamily of trypsin-like serine proteinases implicated in asthma. Unlike beta-tryptases, alpha-tryptases apparently are proteolytically inactive. We have solved the 2.2A crystal structure of mature human alpha1-tryptase. It reveals a frame-like tetrameric architecture that, surprisingly, does not require heparin-binding for stability. In marked contrast to beta2-tryptase, the Ser214-Gly219 segment, which normally provides the template for substrate binding, is kinked in alpha-tryptase, thereby blocking its non-primed subsites. This so far unobserved subsite distortion is incompatible with productive substrate binding and processing. alpha-Tryptase apparently is trapped in this off-conformation by repulsions and attractions of the Asp216 side-chain. However, proteolytic activity could be generated by an induced-fit mechanism.
About this StructureAbout this Structure
1LTO is a Single protein structure of sequence from Homo sapiens. Active as Tryptase, with EC number 3.4.21.59 Full crystallographic information is available from OCA.
ReferenceReference
The crystal structure of human alpha1-tryptase reveals a blocked substrate-binding region., Marquardt U, Zettl F, Huber R, Bode W, Sommerhoff C, J Mol Biol. 2002 Aug 16;321(3):491-502. PMID:12162961
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