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1gob
From Proteopedia
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| - | [[Image:1gob.jpg|left|200px]] | + | [[Image:1gob.jpg|left|200px]] |
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| - | '''COOPERATIVE STABILIZATION OF ESCHERICHIA COLI RIBONUCLEASE HI BY INSERTION OF GLY-80B AND GLY-77-> ALA SUBSTITUTION''' | + | {{Structure |
| + | |PDB= 1gob |SIZE=350|CAPTION= <scene name='initialview01'>1gob</scene>, resolution 2.0Å | ||
| + | |SITE= | ||
| + | |LIGAND= | ||
| + | |ACTIVITY= [http://en.wikipedia.org/wiki/Ribonuclease_H Ribonuclease H], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.26.4 3.1.26.4] | ||
| + | |GENE= | ||
| + | }} | ||
| + | |||
| + | '''COOPERATIVE STABILIZATION OF ESCHERICHIA COLI RIBONUCLEASE HI BY INSERTION OF GLY-80B AND GLY-77-> ALA SUBSTITUTION''' | ||
| + | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 1GOB is a [ | + | 1GOB is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1GOB OCA]. |
==Reference== | ==Reference== | ||
| - | Cooperative stabilization of Escherichia coli ribonuclease HI by insertion of Gly-80b and Gly-77-->Ala substitution., Ishikawa K, Nakamura H, Morikawa K, Kimura S, Kanaya S, Biochemistry. 1993 Jul 20;32(28):7136-42. PMID:[http:// | + | Cooperative stabilization of Escherichia coli ribonuclease HI by insertion of Gly-80b and Gly-77-->Ala substitution., Ishikawa K, Nakamura H, Morikawa K, Kimura S, Kanaya S, Biochemistry. 1993 Jul 20;32(28):7136-42. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/8393706 8393706] |
[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
[[Category: Ribonuclease H]] | [[Category: Ribonuclease H]] | ||
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[[Category: hydrolase(endoribonuclease)]] | [[Category: hydrolase(endoribonuclease)]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 11:25:49 2008'' |
Revision as of 09:25, 20 March 2008
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| , resolution 2.0Å | |||||||
|---|---|---|---|---|---|---|---|
| Activity: | Ribonuclease H, with EC number 3.1.26.4 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
COOPERATIVE STABILIZATION OF ESCHERICHIA COLI RIBONUCLEASE HI BY INSERTION OF GLY-80B AND GLY-77-> ALA SUBSTITUTION
Overview
The insertion of a Gly residue (designated as Gly-80b) between the C-cap of the alpha II-helix (Gln-80) and the N-cap of the alpha III-helix (Trp-81) in Escherichia coli ribonuclease HI enhances the protein stability by 0.4 kcal/mol in delta G (Kimura, S., Nakamura, H., Hashimoto, T., Oobatake, M., & Kanaya, S. (1992) J. Biol. Chem. 267, 21535-21542). Another mutation within the alpha II-helix, Gly-77-->Ala, reduces the stability by 0.9 kcal/mol. Simultaneous introduction of these mutations enhances the stability by 0.8 kcal/mol, indicating that the effects of these mutations are cooperative and not simply independent. We determined the crystal structures of these three mutant proteins (G80b-, A77-, and A77/G80b-RNase H) to investigate this cooperative mechanism of the protein stabilization. The structures revealed that the inserted Gly-80b assumes a left-handed helical conformation in both the G80b- and the A77/G80b-RNase H. This inserted glycine residue allows the formation of a "paperclip", which is a common motif at the C-termini of alpha-helices. Accompanying the formation of the paperclip motif, two intrahelical hydrogen bonds are formed between the backbone atoms (O78-N80b and O80b-N84). The stabilization caused by the insertion of Gly-80b can be ascribed to the formation of these hydrogen bonds. The Gly-77-->Ala substitution destabilizes the protein due to the deformed packing interactions in the hydrophobic core around Ala-77 and the stress in the wedged indole ring of Trp-81. These effects are alleviated by the insertion of Gly-80b, which relaxes the backbone structure.(ABSTRACT TRUNCATED AT 250 WORDS)
About this Structure
1GOB is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Cooperative stabilization of Escherichia coli ribonuclease HI by insertion of Gly-80b and Gly-77-->Ala substitution., Ishikawa K, Nakamura H, Morikawa K, Kimura S, Kanaya S, Biochemistry. 1993 Jul 20;32(28):7136-42. PMID:8393706
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