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R-proteins in modification deficient ribosomes - dissociated 50S subunits from 70S

ABSTRACT: Ribosomal RNA modifications are introduced by specific enzymes during ribosome assembly in bacteria. Deletion of individual modification enzymes has a minor effect on bacterial growth, ribosome biogenesis, and translation, which has complicated the definition of the function of the enzymes and their products. We have constructed an E. coli strain lacking 10 genes encoding enzymes that modify 23S rRNA around the peptidyl-transferase center. This strain exhibits severely compromised growth and ribosome assembly, especially at lower temperatures. Ribosomal protein composition of the mature 50S ribosomes and free 50S subunits was analyzed by SILAC based qMS approach. We have found that absence of 23S rRNA modifications around PTC does not affect significantly r-protein content of incompletely assembled 50S or mature 50S ribosomes.

INSTRUMENT(S): LTQ Orbitrap XL

ORGANISM(S): Escherichia Coli

SUBMITTER: Kaspar Reier

LAB HEAD: Tiina Tamm

PROVIDER: PXD047588 | Pride | 2024-03-15

REPOSITORIES: Pride

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			Action	DRS
	210126_03_Orbi2_KN_SER_G90_T120_Reier_A4_1ug.raw	Raw
	210126_05_Orbi2_KN_SER_G90_T120_Reier_A6_1ug.raw	Raw
	210126_07_Orbi2_KN_SER_G90_T120_Reier_A2_1ug.raw	Raw
	210126_09_Orbi2_KN_SER_G90_T120_Reier_A3_1ug.raw	Raw
	210126_11_Orbi2_KN_SER_G90_T120_Reier_A5_1ug.raw	Raw

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R-proteins in modification deficient ribosomes - free 50S subunits

Project description:Ribosomal RNA modifications are introduced by specific enzymes during ribosome assembly in bacteria. Deletion of individual modification enzymes has a minor effect on bacterial growth, ribosome biogenesis, and translation, which has complicated the definition of the function of the enzymes and their products. We have constructed an E. coli strain lacking 10 genes encoding enzymes that modify 23S rRNA around the peptidyl-transferase center. This strain exhibits severely compromised growth and ribosome assembly, especially at lower temperatures. Ribosomal protein composition of the mature 50S ribosomes and free 50S subunits was analyzed by SILAC based qMS approach. We have found that absence of 23S rRNA modifications around PTC does not affect significantly r-protein content of incompletely assembled 50S or mature 50S ribosomes.

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