1mwk
From Proteopedia
(New page: 200px<br /><applet load="1mwk" size="450" color="white" frame="true" align="right" spinBox="true" caption="1mwk, resolution 2.3Å" /> '''ParM from plasmid R1 ...) |
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| - | [[Image:1mwk.gif|left|200px]]<br /><applet load="1mwk" size=" | + | [[Image:1mwk.gif|left|200px]]<br /><applet load="1mwk" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1mwk, resolution 2.3Å" /> | caption="1mwk, resolution 2.3Å" /> | ||
'''ParM from plasmid R1 APO form'''<br /> | '''ParM from plasmid R1 APO form'''<br /> | ||
==Overview== | ==Overview== | ||
| - | It was the general belief that DNA partitioning in prokaryotes is | + | It was the general belief that DNA partitioning in prokaryotes is independent of a cytoskeletal structure, which in eukaryotic cells is indispensable for DNA segregation. Recently, however, immunofluorescence microscopy revealed highly dynamic, filamentous structures along the longitudinal axis of Escherichia coli formed by ParM, a plasmid-encoded protein required for accurate segregation of low-copy-number plasmid R1. We show here that ParM polymerizes into double helical protofilaments with a longitudinal repeat similar to filamentous actin (F-actin) and MreB filaments that maintain the cell shape of non-spherical bacteria. The crystal structure of ParM with and without ADP demonstrates that it is a member of the actin family of proteins and shows a domain movement of 25 degrees upon nucleotide binding. Furthermore, the crystal structure of ParM reveals major differences in the protofilament interface compared with F-actin, despite the similar arrangement of the subunits within the filaments. Thus, there is now evidence for cytoskeletal structures, formed by actin-like filaments that are involved in plasmid partitioning in E.coli. |
==About this Structure== | ==About this Structure== | ||
| - | 1MWK is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http:// | + | 1MWK is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1MWK OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Amos, L | + | [[Category: Amos, L A.]] |
| - | [[Category: Ent, F | + | [[Category: Ent, F Van den.]] |
[[Category: Gerdes, K.]] | [[Category: Gerdes, K.]] | ||
[[Category: Lowe, J.]] | [[Category: Lowe, J.]] | ||
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[[Category: plasmid partition]] | [[Category: plasmid partition]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:59:52 2008'' |
Revision as of 11:59, 21 February 2008
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ParM from plasmid R1 APO form
Overview
It was the general belief that DNA partitioning in prokaryotes is independent of a cytoskeletal structure, which in eukaryotic cells is indispensable for DNA segregation. Recently, however, immunofluorescence microscopy revealed highly dynamic, filamentous structures along the longitudinal axis of Escherichia coli formed by ParM, a plasmid-encoded protein required for accurate segregation of low-copy-number plasmid R1. We show here that ParM polymerizes into double helical protofilaments with a longitudinal repeat similar to filamentous actin (F-actin) and MreB filaments that maintain the cell shape of non-spherical bacteria. The crystal structure of ParM with and without ADP demonstrates that it is a member of the actin family of proteins and shows a domain movement of 25 degrees upon nucleotide binding. Furthermore, the crystal structure of ParM reveals major differences in the protofilament interface compared with F-actin, despite the similar arrangement of the subunits within the filaments. Thus, there is now evidence for cytoskeletal structures, formed by actin-like filaments that are involved in plasmid partitioning in E.coli.
About this Structure
1MWK is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
F-actin-like filaments formed by plasmid segregation protein ParM., van den Ent F, Moller-Jensen J, Amos LA, Gerdes K, Lowe J, EMBO J. 2002 Dec 16;21(24):6935-43. PMID:12486014
Page seeded by OCA on Thu Feb 21 13:59:52 2008
