1trq: Difference between revisions
New page: left|200px<br /><applet load="1trq" size="450" color="white" frame="true" align="right" spinBox="true" caption="1trq, resolution 2.3Å" /> '''X-RAY CRYSTALLOGRAPHI... |
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[[Image:1trq.gif|left|200px]]<br /><applet load="1trq" size=" | [[Image:1trq.gif|left|200px]]<br /><applet load="1trq" size="350" color="white" frame="true" align="right" spinBox="true" | ||
caption="1trq, resolution 2.3Å" /> | caption="1trq, resolution 2.3Å" /> | ||
'''X-RAY CRYSTALLOGRAPHIC AND CALORIMERIC STUDIES OF THE EFFECTS OF THE MUTATION TRP 59 TYR IN RIBONUCLEASE T1'''<br /> | '''X-RAY CRYSTALLOGRAPHIC AND CALORIMERIC STUDIES OF THE EFFECTS OF THE MUTATION TRP 59 TYR IN RIBONUCLEASE T1'''<br /> | ||
==Overview== | ==Overview== | ||
Two mutants of ribonuclease T1 (RNaseT1), [59-tyrosine]ribonuclease T1 | Two mutants of ribonuclease T1 (RNaseT1), [59-tyrosine]ribonuclease T1 (W59Y) and [45-tryptophan,59-tyrosine]ribonuclease T1 (Y45W/W59Y) possess between 150% and 190% wild-type activity. They have been crystallised as complexes of the inhibitor 2'-guanylic acid and analysed by X-ray diffraction at resolutions of 0.23 nm and 0.24 nm, respectively. The space group for both is monoclinic, P2(1), with two molecules/asymmetric unit, W59Y: a = 4.934 nm, b = 4.820 nm, c = 4.025 nm, beta = 90.29 degrees. Y45W/W59Y: a = 4.915 nm, b = 4.815 nm, c = 4.015 nm, beta = 90.35 degrees. Compared to wild-type RNaseT1 in complex with 2'-guanylic acid (2'GMP) both mutant inhibitor complexes indicate that the replacement of Trp59 by Tyr leads to a 0.04-nm inward shift of the single alpha-helix and to significant differences in the active-site geometry, inhibitor conformation and inhibitor binding. Calorimetric studies of a range of mutants [24-tryptophan]ribonuclease T1 (Y24W), [42-tryptophan]ribonuclease T1 (Y42W), [45-tryptophan]ribonuclease T1 (Y45W), [92-alanine]ribonuclease T1 (H92A) and [92-threonine]ribonuclease T1 (H92T) with and without the further mutation Trp59-->Tyr showed that mutant proteins for which Trp59 is replaced by Tyr exhibit slightly decreased thermal stability. | ||
==About this Structure== | ==About this Structure== | ||
1TRQ is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Aspergillus_oryzae Aspergillus oryzae] with CA and 2GP as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Ribonuclease_T(1) Ribonuclease T(1)], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.27.3 3.1.27.3] Full crystallographic information is available from [http:// | 1TRQ is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Aspergillus_oryzae Aspergillus oryzae] with <scene name='pdbligand=CA:'>CA</scene> and <scene name='pdbligand=2GP:'>2GP</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Ribonuclease_T(1) Ribonuclease T(1)], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.27.3 3.1.27.3] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1TRQ OCA]. | ||
==Reference== | ==Reference== | ||
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[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Saenger, W.]] | [[Category: Saenger, W.]] | ||
[[Category: Schubert, W | [[Category: Schubert, W D.]] | ||
[[Category: 2GP]] | [[Category: 2GP]] | ||
[[Category: CA]] | [[Category: CA]] | ||
[[Category: hydrolase(endoribonuclease)]] | [[Category: hydrolase(endoribonuclease)]] | ||
''Page seeded by [http:// | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 15:16:40 2008'' | ||
Revision as of 16:16, 21 February 2008
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X-RAY CRYSTALLOGRAPHIC AND CALORIMERIC STUDIES OF THE EFFECTS OF THE MUTATION TRP 59 TYR IN RIBONUCLEASE T1
OverviewOverview
Two mutants of ribonuclease T1 (RNaseT1), [59-tyrosine]ribonuclease T1 (W59Y) and [45-tryptophan,59-tyrosine]ribonuclease T1 (Y45W/W59Y) possess between 150% and 190% wild-type activity. They have been crystallised as complexes of the inhibitor 2'-guanylic acid and analysed by X-ray diffraction at resolutions of 0.23 nm and 0.24 nm, respectively. The space group for both is monoclinic, P2(1), with two molecules/asymmetric unit, W59Y: a = 4.934 nm, b = 4.820 nm, c = 4.025 nm, beta = 90.29 degrees. Y45W/W59Y: a = 4.915 nm, b = 4.815 nm, c = 4.015 nm, beta = 90.35 degrees. Compared to wild-type RNaseT1 in complex with 2'-guanylic acid (2'GMP) both mutant inhibitor complexes indicate that the replacement of Trp59 by Tyr leads to a 0.04-nm inward shift of the single alpha-helix and to significant differences in the active-site geometry, inhibitor conformation and inhibitor binding. Calorimetric studies of a range of mutants [24-tryptophan]ribonuclease T1 (Y24W), [42-tryptophan]ribonuclease T1 (Y42W), [45-tryptophan]ribonuclease T1 (Y45W), [92-alanine]ribonuclease T1 (H92A) and [92-threonine]ribonuclease T1 (H92T) with and without the further mutation Trp59-->Tyr showed that mutant proteins for which Trp59 is replaced by Tyr exhibit slightly decreased thermal stability.
About this StructureAbout this Structure
1TRQ is a Single protein structure of sequence from Aspergillus oryzae with and as ligands. Active as Ribonuclease T(1), with EC number 3.1.27.3 Full crystallographic information is available from OCA.
ReferenceReference
X-ray crystallographic and calorimetric studies of the effects of the mutation Trp59-->Tyr in ribonuclease T1., Schubert WD, Schluckebier G, Backmann J, Granzin J, Kisker C, Choe HW, Hahn U, Pfeil W, Saenger W, Eur J Biochem. 1994 Mar 1;220(2):527-34. PMID:8125111
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