Thiolation of transfer RNA in Escherichia coli varies with growth rate.

AUTOR(ES)

Emilsson, V

RESUMO

We have used an affinity electrophoresis assay which when combined with Northern hybridization techniques permits us to estimate the degree of thiolation of individual tRNA species in Escherichia coli. We observe that the levels of 4-thio 2'(3')-uridine (4-thioU) in many but not all tRNAs varies dramatically at different bacterial growth rates: Five tRNAs are completely thiolated at all growth rates, while another eight tRNAs are incompletely thiolated and the fraction of the unthiolated form of these tRNA species increases as the growth rates increase. Transfer RNA(2Glu) contains 4-thioU as well as (methylamino)methyl-2-thio uridine (mnm(5)2-thioU). The level of mnm(5)2-thioU of tRNA(2Glu) is invariant with growth rate. Surprisingly, none of the thirteen tRNA species that we have studied is completely unmodified in all growth media. In particular, at the slowest growth rates every tRNA class that we have studied contains a form that has 4-thioU residues.

Documentos Relacionados

• The RNA chain elongation rate in Escherichia coli depends on the growth rate.
• The stability of mRNA for eucaryotic elongation factor Tu in Friend erythroleukemia cells varies with growth rate.
• Growth rate dependence of transfer RNA abundance in Escherichia coli.
• Escherichia coli ribosomes translate in vivo with variable rate.
• The Escherichia coli lov gene product connects peptidoglycan synthesis, ribosomes and growth rate.