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6mpl

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Revision as of 11:26, 1 January 2020

Racemic M2-TM I39A crystallized from racemic detergent

Structural highlights

6mpl is a 1 chain structure. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:	,
NonStd Res:	,
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[M2_I97A1] Forms a proton-selective ion channel that is necessary for the efficient release of the viral genome during virus entry. After attaching to the cell surface, the virion enters the cell by endocytosis. Acidification of the endosome triggers M2 ion channel activity. The influx of protons into virion interior is believed to disrupt interactions between the viral ribonucleoprotein (RNP), matrix protein 1 (M1), and lipid bilayers, thereby freeing the viral genome from interaction with viral proteins and enabling RNA segments to migrate to the host cell nucleus, where influenza virus RNA transcription and replication occur. Also plays a role in viral proteins secretory pathway. Elevates the intravesicular pH of normally acidic compartments, such as trans-Golgi network, preventing newly formed hemagglutinin from premature switching to the fusion-active conformation.

Publication Abstract from PubMed

The structural principles that govern interactions between l- and d-peptides are not well understood. Among natural proteins, coiled-coil assemblies formed between or among alpha-helices are the most regular feature of tertiary and quaternary structures. We recently reported the first high-resolution structures for heterochiral coiled-coil dimers, which represent a starting point for understanding associations of l- and d-polypeptides. These structures were an unexpected outcome from crystallization of a racemic peptide corresponding to the transmembrane domain of the influenza A M2 protein (M2-TM). The reported structures raised the possibility that heterochiral coiled-coil dimers prefer an 11-residue (hendecad) sequence repeat, in contrast to the 7-residue (heptad) sequence repeat that is dominant among natural coiled coils. To gain insight on sequence repeat preferences of heterochiral coiled-coils, we have examined three M2-TM variants containing substitutions intended to minimize steric clashes between side chains at the coiled-coil interface. In each of the three new crystal structures, we observed heterochiral coiled-coil associations that closely match a hendecad sequence motif, which strengthens the conclusion that this motif is intrinsic to the pairing of alpha-helices with opposite handedness. In each case, the presence of a hendecad motif was established by comparing the observed helical frequency to that of an ideal hendecad. This comparison revealed that decreasing the size of the amino acid side chain at positions that project toward the superhelical axis produces tighter packing, as determined by the size of the coiled-coil radius. These results provide a basis for future design of heterochiral coiled-coil pairings.

A Hendecad Motif Is Preferred for Heterochiral Coiled-Coil Formation.,Kreitler DF, Yao Z, Steinkruger JD, Mortenson DE, Huang L, Mittal R, Travis BR, Forest KT, Gellman SH J Am Chem Soc. 2019 Jan 15. doi: 10.1021/jacs.8b11246. PMID:30645104^[1]

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

References

↑ Kreitler DF, Yao Z, Steinkruger JD, Mortenson DE, Huang L, Mittal R, Travis BR, Forest KT, Gellman SH. A Hendecad Motif Is Preferred for Heterochiral Coiled-Coil Formation. J Am Chem Soc. 2019 Jan 15. doi: 10.1021/jacs.8b11246. PMID:30645104 doi:http://dx.doi.org/10.1021/jacs.8b11246

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

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/6mpl"

@@ Line 1: / Line 1: @@
 ==Racemic M2-TM I39A crystallized from racemic detergent==
-<StructureSection load='6mpl' size='340' side='right' caption='[[6mpl]], [[Resolution|resolution]] 1.55&Aring;' scene=''>
+<StructureSection load='6mpl' size='340' side='right'caption='[[6mpl]], [[Resolution|resolution]] 1.55&Aring;' scene=''>
 == Structural highlights ==
 <table><tr><td colspan='2'>[[6mpl]] is a 1 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6MPL OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6MPL FirstGlance]. <br>
@@ Line 19: / Line 19: @@
 </div>
 <div class="pdbe-citations 6mpl" style="background-color:#fffaf0;"></div>
+==See Also==
+*[[M2 protein|M2 protein]]
 == References ==
 <references/>
 __TOC__
 </StructureSection>
+[[Category: Large Structures]]
 [[Category: Forest, K T]]
 [[Category: Gellman, S H]]

6mpl

From Proteopedia

Revision as of 11:26, 1 January 2020

Racemic M2-TM I39A crystallized from racemic detergent

Structural highlights

Function

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

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