3J3W: Atomic Model Of The Immature 50s Subunit From Bacillus Subtilis (state Ii-a)

Citation:
Abstract
Ribosome assembly is a process fundamental for all cellular activities. The efficiency and accuracy of the subunit assembly are tightly regulated and closely monitored. In the present work, we characterized, both compositionally and structurally, a set of in vivo 50S subunit precursors (45S), isolated from a mutant bacterial strain. Our qualitative mass spectrometry data indicate that L28, L16, L33, L36 and L35 are dramatically underrepresented in the 45S particles. This protein spectrum shows interesting similarity to many qualitatively analyzed 50S precursors from different genetic background, indicating the presence of global rate-limiting steps in the late-stage assembly of 50S subunit. Our structural data reveal two major intermediate states for the 45S particles. Consistently, both states severally lack those proteins, but they also differ in the stability of the functional centers of the 50S subunit, demonstrating that they are translationally inactive. Detailed analysis indicates that the orientation of H38 accounts for the global conformational differences in these intermediate structures, and suggests that the reorientation of H38 to its native position is rate-limiting during the late-stage assembly. Especially, H38 plays an essential role in stabilizing the central protuberance, through the interaction with the 5S rRNA, and the correctly orientated H38 is likely a prerequisite for further maturation of the 50S subunit.
PDB ID: 3J3WDownload
MMDB ID: 110802
PDB Deposition Date: 2013/4/28
Updated in MMDB: 2013/08
Experimental Method:
electron microscopy
Resolution: 10.7  Å
Source Organism:
Similar Structures:
Biological Unit for 3J3W: eicosameric; determined by author
Molecular Components in 3J3W
Label Count Molecule
Proteins (19 molecules)
1
50S Ribosomal Protein L32(Gene symbol: rpmF)
Molecule annotation
1
50S Ribosomal Protein L2(Gene symbol: rplB)
Molecule annotation
1
50S Ribosomal Protein L17(Gene symbol: rplQ)
Molecule annotation
1
50S Ribosomal Protein L6(Gene symbol: rplF)
Molecule annotation
1
50S Ribosomal Protein L13(Gene symbol: rplM)
Molecule annotation
1
50S Ribosomal Protein L14(Gene symbol: rplN)
Molecule annotation
1
50S Ribosomal Protein L15(Gene symbol: rplO)
Molecule annotation
1
50S Ribosomal Protein L19
Molecule annotation
1
50S Ribosomal Protein L20(Gene symbol: rplT)
Molecule annotation
1
50S Ribosomal Protein L3(Gene symbol: rplC)
Molecule annotation
1
50S Ribosomal Protein L21(Gene symbol: rplU)
Molecule annotation
1
50S Ribosomal Protein L22(Gene symbol: rplV)
Molecule annotation
1
50S Ribosomal Protein L23(Gene symbol: rplW)
Molecule annotation
1
50S Ribosomal Protein L24(Gene symbol: rplX)
Molecule annotation
1
50S Ribosomal Protein L29(Gene symbol: rpmC)
Molecule annotation
1
50S Ribosomal Protein L34(Gene symbol: rpmH)
Molecule annotation
1
50S Ribosomal Protein L1(Gene symbol: rplA)
Molecule annotation
1
50S Ribosomal Protein L11(Gene symbol: rplK)
Molecule annotation
1
50S Ribosomal Protein L4(Gene symbol: rplD)
Molecule annotation
Nucleotide(1 molecule)
1
Ribosome RNA 23S
Molecule annotation
* Click molecule labels to explore molecular sequence information.

Citing MMDB
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