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1rbu

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Revision as of 06:54, 29 November 2017

STRUCTURAL STUDY OF MUTANTS OF ESCHERICHIA COLI RIBONUCLEASE HI WITH ENHANCED THERMOSTABILITY

Structural highlights

1rbu is a 1 chain structure with sequence from "bacillus_coli"_migula_1895 "bacillus coli" migula 1895. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Activity:	Ribonuclease H, with EC number 3.1.26.4
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[RNH_ECOLI] Endonuclease that specifically degrades the RNA of RNA-DNA hybrids. RNase H participates in DNA replication; it helps to specify the origin of genomic replication by suppressing initiation at origins other than the oriC locus; along with the 5'-3' exonuclease of pol1, it removes RNA primers from the Okazaki fragments of lagging strand synthesis; and it defines the origin of replication for ColE1-type plasmids by specific cleavage of an RNA preprimer.[HAMAP-Rule:MF_00042]

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

Systematic replacement of the amino acid residues in Escherichia coli ribonuclease HI with those in the thermophilic counterpart has revealed that two mutations, His62-->Pro (H62P) and Lys95-->Gly (K95G), increased the thermostability of the protein. These single-site mutant proteins, together with the mutant proteins His62-->Ala (H62A), Lys95-->Asn (K95N) and Lys95-->Ala (K95A), were crystallized and their structures were determined at 1.8 A resolution. The crystal structures of these mutant proteins reveal that only the local structure around each mutation site is essential for the increase in thermostability. For each mutant protein, the stabilization mechanism is considered to be as follows: (i) H62P is stabilized because of a decrease in the entropy of the unfolded state, without a change in the native backbone structure; (ii) K95G is stabilized since the strain caused by the left-handed backbone structure in the typical 3:5 type loop is eliminated; and (iii) K95N is slightly stabilized by a hydrogen bond formed between the side-chain N delta-atom of the mutated aspargine residue and the main-chain carbonyl oxygen within the same residue.

Structural study of mutants of Escherichia coli ribonuclease HI with enhanced thermostability.,Ishikawa K, Kimura S, Kanaya S, Morikawa K, Nakamura H Protein Eng. 1993 Jan;6(1):85-91. PMID:8381958^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Ishikawa K, Kimura S, Kanaya S, Morikawa K, Nakamura H. Structural study of mutants of Escherichia coli ribonuclease HI with enhanced thermostability. Protein Eng. 1993 Jan;6(1):85-91. PMID:8381958

1 Structural highlights
2 Function
3 Evolutionary Conservation
4 Publication Abstract from PubMed
5 See Also
6 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1rbu"

@@ Line 1: / Line 1: @@
 ==STRUCTURAL STUDY OF MUTANTS OF ESCHERICHIA COLI RIBONUCLEASE HI WITH ENHANCED THERMOSTABILITY==
 <StructureSection load='1rbu' size='340' side='right' caption='[[1rbu]], [[Resolution|resolution]] 1.80&Aring;' scene=''>
@@ Line 4: / Line 5: @@
 <table><tr><td colspan='2'>[[1rbu]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/"bacillus_coli"_migula_1895 "bacillus coli" migula 1895]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1RBU OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1RBU FirstGlance]. <br>
 </td></tr><tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[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] </span></td></tr>
-<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1rbu FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1rbu OCA], [http://pdbe.org/1rbu PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1rbu RCSB], [http://www.ebi.ac.uk/pdbsum/1rbu PDBsum]</span></td></tr>
+<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1rbu FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1rbu OCA], [http://pdbe.org/1rbu PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1rbu RCSB], [http://www.ebi.ac.uk/pdbsum/1rbu PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=1rbu ProSAT]</span></td></tr>
 </table>
 == Function ==
@@ Line 29: / Line 30: @@
 ==See Also==
-*[[Ribonuclease|Ribonuclease]]
 *[[Temp|Temp]]
 == References ==

1rbu

From Proteopedia

Revision as of 06:54, 29 November 2017

STRUCTURAL STUDY OF MUTANTS OF ESCHERICHIA COLI RIBONUCLEASE HI WITH ENHANCED THERMOSTABILITY

Structural highlights

Function

Evolutionary Conservation

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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