2rns: Difference between revisions
No edit summary |
No edit summary |
||
| Line 1: | Line 1: | ||
[[Image:2rns.jpg|left|200px]] | [[Image:2rns.jpg|left|200px]] | ||
<!-- | |||
The line below this paragraph, containing "STRUCTURE_2rns", creates the "Structure Box" on the page. | |||
You may change the PDB parameter (which sets the PDB file loaded into the applet) | |||
or the SCENE parameter (which sets the initial scene displayed when the page is loaded), | |||
or leave the SCENE parameter empty for the default display. | |||
| | --> | ||
| | {{STRUCTURE_2rns| PDB=2rns | SCENE= }} | ||
}} | |||
'''REFINEMENT OF THE CRYSTAL STRUCTURE OF RIBONUCLEASE S. COMPARISON WITH AND BETWEEN THE VARIOUS RIBONUCLEASE A STRUCTURES''' | '''REFINEMENT OF THE CRYSTAL STRUCTURE OF RIBONUCLEASE S. COMPARISON WITH AND BETWEEN THE VARIOUS RIBONUCLEASE A STRUCTURES''' | ||
| Line 19: | Line 16: | ||
==About this Structure== | ==About this Structure== | ||
2RNS is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Bos_taurus Bos taurus]. This structure supersedes the now removed PDB entry | 2RNS is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Bos_taurus Bos taurus]. This structure supersedes the now removed PDB entry [http://oca.weizmann.ac.il/oca-bin/send-pdb?obs=1&id=1rns 1rns]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2RNS OCA]. | ||
==Reference== | ==Reference== | ||
| Line 30: | Line 27: | ||
[[Category: Varadarajan, R.]] | [[Category: Varadarajan, R.]] | ||
[[Category: Wyckoff, H W.]] | [[Category: Wyckoff, H W.]] | ||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun May 4 17:13:45 2008'' | |||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | |||
Revision as of 17:13, 4 May 2008
REFINEMENT OF THE CRYSTAL STRUCTURE OF RIBONUCLEASE S. COMPARISON WITH AND BETWEEN THE VARIOUS RIBONUCLEASE A STRUCTURES
OverviewOverview
Ribonuclease S (RNase-S) is a complex that consists of two proteolytic fragments of bovine pancreatic ribonuclease A (RNase-A): the S-peptide (residues 1-20) and S-protein (residues 21-124). We have refined the crystal structures of three RNase-S complexes. The first two contain the full-length 20-residue S-peptide and were studied at pHs of 4.75 and 5.5. The third one consists of a truncated form of S-peptide (residues 1-15) and was studied at pH 4.75 as the reference structure for a series of mutant peptide complexes to be reported separately. Excluding residues 16-23 which are either missing (in the S15 complex) or disordered (in both S20 complexes), all three structures refined at 1.6-A resolution are identical within the estimated errors in the coordinates (0.048 A for the backbone atoms). The R-values, residual error, range from 17.4% to 18.6%. The final model of S20, pH 4.75, includes 1 sulfate and 84 water molecules. The side chains of 11 residues were modeled in two discrete conformations. The final structures were independent of the particular RNase-A or RNase-S used as a starting model. An extensive comparison with refined crystal structures of RNase-A reveals that the core of the molecule which is held together with extensive hydrogen bonds is in identical pattern in all cases. However, the loop regions vary from one structure to another and are often characterized by high B-factors. The pattern of thermal parameters appears to be dependent on crystal packing and correlates well with the accessibility calculated in the crystal. Gln60 is a conserved residue in all sequences known to date for this class of ribonucleases. However, it is the only residue that is clearly defined in an unfavorable position (phi = -100 degrees, psi = -130 degrees) on the Ramachandran plot. The origin of the substantial differences between RNase-A and RNase-S in stability to both acid and temperature denaturation and in susceptibility to proteolysis at neutral pH is not obvious in our visual comparison of these two structures.
About this StructureAbout this Structure
2RNS is a Single protein structure of sequence from Bos taurus. This structure supersedes the now removed PDB entry 1rns. Full crystallographic information is available from OCA.
ReferenceReference
Refinement of the crystal structure of ribonuclease S. Comparison with and between the various ribonuclease A structures., Kim EE, Varadarajan R, Wyckoff HW, Richards FM, Biochemistry. 1992 Dec 15;31(49):12304-14. PMID:1463719 Page seeded by OCA on Sun May 4 17:13:45 2008