Abstract:
:We find that the transcription of various ribosomal proteins can be differentially affected by polyamines and by changes in growth rates. Using strain MG1655 of Escherichia coli K-12 (F-, lambda-), we have determined the effects of polyamines and changes in growth rate on the transcription of several ribosomal genes and the polyamine-synthesizing enzymes ornithine decarboxylase (L-ornithine carboxy-lyase; EC 4.1.1.17) and arginine decarboxylase (L-arginine carboxylyase; EC 4.1.1.19). Ribosomal proteins S20 and L34 can be differentiated from the other ribosomal proteins studied; the transcription of S20 and L34 is especially sensitive to polyamines and less sensitive to changes in growth rates. In contrast, the transcription of S10, S15, S19, L2, L4, L20, L22, and L23 is insensitive to polyamines although it is particularly sensitive to changes in growth rates. Like S20 and L34, the transcription of ornithine decarboxylase and arginine decarboxylase is especially sensitive to polyamines. Polyamines specifically enhance the transcription of ribosomal proteins S20 and L34, and decrease that of ornithine decarboxylase and arginine decarboxylase. It is evident that polyamines can exert both positive and negative regulation of gene expression in E. coli that can be differentiated from the effects caused by changes in growth rates.
journal_name
Proc Natl Acad Sci U S Aauthors
Huang SC,Panagiotidis CA,Canellakis ESdoi
10.1073/pnas.87.9.3464subject
Has Abstractpub_date
1990-05-01 00:00:00pages
3464-8issue
9eissn
0027-8424issn
1091-6490journal_volume
87pub_type
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