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1uun

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Revision as of 07:04, 24 July 2019

Main porin from Mycobacterium smegmatis (MspA)

Structural highlights

1uun is a 2 chain structure with sequence from "bacillus_smegmatis"_trevisan_1889 "bacillus smegmatis" trevisan 1889. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[MSPA_MYCS2] The major porin in this organism, forms a water-filled channel which favors the permeation of cations, amino acids, iron Fe(3+) and less efficiently phosphate. Does not transport Fe-ExoMS, the predominant siderophore. Plays a role in transport of beta-lactamase and hydrophilic fluoroquinolone antibiotics such as norfloxacin as well as chloramphenicol. There are about 2400 porins in wild-type, 800 in an mspA deletion and 150 in a double mspA-mspC deletion. Different conductance values with maxima at 2.3 and 4.6 nanosiemens might be caused by a simultaneous reconstitution of MspA channels into the membrane or by the existence of different MspA conformations.^[1] ^[2] ^[3] ^[4] ^[5]

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

Mycobacteria have low-permeability outer membranes that render them resistant to most antibiotics. Hydrophilic nutrients can enter by way of transmembrane-channel proteins called porins. An x-ray analysis of the main porin from Mycobacterium smegmatis, MspA, revealed a homooctameric goblet-like conformation with a single central channel. This is the first structure of a mycobacterial outer-membrane protein. No structure-related protein was found in the Protein Data Bank. MspA contains two consecutive beta barrels with nonpolar outer surfaces that form a ribbon around the porin, which is too narrow to fit the thickness of the mycobacterial outer membrane in contemporary models.

The structure of a mycobacterial outer-membrane channel.,Faller M, Niederweis M, Schulz GE Science. 2004 Feb 20;303(5661):1189-92. PMID:14976314^[6]

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

References

↑ Niederweis M, Ehrt S, Heinz C, Klocker U, Karosi S, Swiderek KM, Riley LW, Benz R. Cloning of the mspA gene encoding a porin from Mycobacterium smegmatis. Mol Microbiol. 1999 Sep;33(5):933-45. PMID:10476028
↑ Stephan J, Bender J, Wolschendorf F, Hoffmann C, Roth E, Mailander C, Engelhardt H, Niederweis M. The growth rate of Mycobacterium smegmatis depends on sufficient porin-mediated influx of nutrients. Mol Microbiol. 2005 Nov;58(3):714-30. PMID:16238622 doi:http://dx.doi.org/10.1111/j.1365-2958.2005.04878.x
↑ Wolschendorf F, Mahfoud M, Niederweis M. Porins are required for uptake of phosphates by Mycobacterium smegmatis. J Bacteriol. 2007 Mar;189(6):2435-42. Epub 2007 Jan 5. PMID:17209034 doi:http://dx.doi.org/10.1128/JB.01600-06
↑ Danilchanka O, Pavlenok M, Niederweis M. Role of porins for uptake of antibiotics by Mycobacterium smegmatis. Antimicrob Agents Chemother. 2008 Sep;52(9):3127-34. doi: 10.1128/AAC.00239-08., Epub 2008 Jun 16. PMID:18559650 doi:http://dx.doi.org/10.1128/AAC.00239-08
↑ Jones CM, Niederweis M. Role of porins in iron uptake by Mycobacterium smegmatis. J Bacteriol. 2010 Dec;192(24):6411-7. doi: 10.1128/JB.00986-10. Epub 2010 Oct 15. PMID:20952578 doi:http://dx.doi.org/10.1128/JB.00986-10
↑ Faller M, Niederweis M, Schulz GE. The structure of a mycobacterial outer-membrane channel. Science. 2004 Feb 20;303(5661):1189-92. PMID:14976314 doi:10.1126/science.1094114

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/1uun"

@@ Line 1: / Line 1: @@
 ==Main porin from Mycobacterium smegmatis (MspA)==
-<StructureSection load='1uun' size='340' side='right' caption='[[1uun]], [[Resolution|resolution]] 2.50&Aring;' scene=''>
+<StructureSection load='1uun' size='340' side='right'caption='[[1uun]], [[Resolution|resolution]] 2.50&Aring;' scene=''>
 == Structural highlights ==
 <table><tr><td colspan='2'>[[1uun]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/"bacillus_smegmatis"_trevisan_1889 "bacillus smegmatis" trevisan 1889]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1UUN OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1UUN FirstGlance]. <br>
@@ Line 35: / Line 35: @@
 </StructureSection>
 [[Category: Bacillus smegmatis trevisan 1889]]
+[[Category: Large Structures]]
 [[Category: Faller, M]]
 [[Category: Niederweis, M]]

1uun

From Proteopedia

Revision as of 07:04, 24 July 2019

Main porin from Mycobacterium smegmatis (MspA)

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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