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1l23

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ENHANCED PROTEIN THERMOSTABILITY FROM SITE-DIRECTED MUTATIONS THAT DECREASE THE ENTROPY OF UNFOLDING

Structural highlights

1l23 is a 1 chain structure with sequence from Escherichia virus T4. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	X-ray diffraction, Resolution 1.7Å
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

ENLYS_BPT4 Endolysin with lysozyme activity that degrades host peptidoglycans and participates with the holin and spanin proteins in the sequential events which lead to the programmed host cell lysis releasing the mature viral particles. Once the holin has permeabilized the host cell membrane, the endolysin can reach the periplasm and break down the peptidoglycan layer.^[1]

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

It is proposed that the stability of a protein can be increased by selected amino acid substitutions that decrease the configurational entropy of unfolding. Two such substitutions, one of the form Xaa----Pro and the other of the form Gly----Xaa, were constructed in bacteriophage T4 lysozyme at sites consistent with the known three-dimensional structure. Both substitutions stabilize the protein toward reversible and irreversible thermal denaturation at physiological pH. The substitutions have no effect on enzymatic activity. High-resolution crystallographic analysis of the proline-containing mutant protein (Ala-82----Pro) shows that its three-dimensional structure is essentially identical with the wild-type enzyme. The overall structure of the other mutant enzyme (Gly-77----Ala) is also very similar to wild-type lysozyme, although there are localized conformational adjustments in the vicinity of the altered amino acid. The combination of a number of such amino acid replacements, each of which is expected to contribute approximately 1 kcal/mol (1 cal = 4.184 J) to the free energy of folding, may provide a general strategy for substantial improvement in the stability of a protein.

Enhanced protein thermostability from site-directed mutations that decrease the entropy of unfolding.,Matthews BW, Nicholson H, Becktel WJ Proc Natl Acad Sci U S A. 1987 Oct;84(19):6663-7. PMID:3477797^[2]

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

References

↑ Moussa SH, Kuznetsov V, Tran TA, Sacchettini JC, Young R. Protein determinants of phage T4 lysis inhibition. Protein Sci. 2012 Apr;21(4):571-82. doi: 10.1002/pro.2042. Epub 2012 Mar 2. PMID:22389108 doi:http://dx.doi.org/10.1002/pro.2042
↑ Matthews BW, Nicholson H, Becktel WJ. Enhanced protein thermostability from site-directed mutations that decrease the entropy of unfolding. Proc Natl Acad Sci U S A. 1987 Oct;84(19):6663-7. PMID:3477797

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/1l23"

Categories: Escherichia virus T4 | Large Structures | Matthews BW | Nicholson H

@@ Line 4: / Line 4: @@
 == Structural highlights ==
 <table><tr><td colspan='2'>[[1l23]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_virus_T4 Escherichia virus T4]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1L23 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1L23 FirstGlance]. <br>
-</td></tr><tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1l23 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1l23 OCA], [https://pdbe.org/1l23 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1l23 RCSB], [https://www.ebi.ac.uk/pdbsum/1l23 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1l23 ProSAT]</span></td></tr>
+</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.7&#8491;</td></tr>
+<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1l23 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1l23 OCA], [https://pdbe.org/1l23 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1l23 RCSB], [https://www.ebi.ac.uk/pdbsum/1l23 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1l23 ProSAT]</span></td></tr>
 </table>
 == Function ==

1l23

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Current revision

ENHANCED PROTEIN THERMOSTABILITY FROM SITE-DIRECTED MUTATIONS THAT DECREASE THE ENTROPY OF UNFOLDING

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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