Abstract
A method is described for measuring the proportion of galactose-specific mRNA (gal-mRNA) in the total RNA extracted from pulse-labelled cells of Escherichia coli K12, by DNA-RNA hybridization with DNA prepared from bacteriophage lambdadg. RNA from wild-type E. coli was compared with RNA from a homogenote carrying the gal operon both in the chromosome and in a substituted sex-factor, and with RNA from a deletion strain that carried the galactose operon only in the exogenote. In each case the cultures were induced with fucose. Under these conditions the amount of gal-mRNA was found to be proportional to the content of galactokinase in the different cultures, and to the gene frequency. The amounts of gal-mRNA in an O(c) mutant and an R(-) mutant were also proportional to the observed contents of galactokinase. In cultures repressed for the enzymes of the galactose operon with thiomethylgalactoside, the content of gal-mRNA was higher than expected from the content of galactokinase. Possible explanations of this finding are discussed.
MeSH Terms
Chromosomes, Bacterial
Coliphages
DNA, Viral
Enzyme Induction
Enzyme Repression
Escherichia coli/analysis,enzymology
Extrachromosomal Inheritance
Fucose
Galactose
Gene Frequency
Genetics, Microbial
Glycosides
Mutation
Nucleic Acid Hybridization
Operon
Phosphotransferases/analysis
RNA, Bacterial/analysis
RNA, Messenger/analysis
Chemicals
DNA, Viral
Glycosides
RNA, Bacterial
RNA, Messenger
Fucose
Phosphotransferases
Galactose
Authors & Affiliations
3 authors, click to expand affiliations / ORCID
Gosden J R
Irving M I
Bishop J O
References (16)
16 references, click to expand
-
Rate of synthesis of messenger ribonucleic acid in Escherichia coli.
J Mol Biol. 1968 Dec;38(3):329-53
PMID: 4887875
-
Transcription of bacteriophage T4 deoxyribonucleic acid in vitro.
Biochem J. 1969 Nov;115(3):353-61
PMID: 4901068
-
Orientation of transcription for the galactose operon as determined by hybridization of gal mRNA with the separated DNA strands of coliphages lambda-dg.
J Mol Biol. 1968 Jul 14;35(1):207-13
PMID: 4939778
-
A method for measuring the content of a specific messenger ribonucleic acid in Escherichia coli.
Biochem J. 1971 Jan;121(1):105-8
PMID: 4940375
-
The number of sex-factors per chromosome in Escherichia coli.
Biochem J. 1971 Jan;121(1):93-103
PMID: 4940379
-
[REGULATORY MECHANISMS IN THE BIOSYNTHESIS OF THE ENZYMES OF GALACTOSE METABOLISM IN ESCHERICHIA COLI K 12. I. THE INDUCED BIOSYNTHESIS OF GALACTOKINASE AND THE SIMULTANEOUS INDUCTION OF THE ENZYMATIC SEQUENCE].
J Mol Biol. 1963 Aug;7:164-82
PMID: 14062650
-
[REGULATORY MECHANISMS IN THE BIOSYNTHESIS OF THE ENZYMES OF GALACTOSE METABOLISM IN ESCHERICHIA COLI K 12. II. THE GENETIC DETERMINISM OF THE REGULATION].
J Mol Biol. 1963 Aug;7:183-205
PMID: 14062651
-
THE ENZYMES OF THE GALACTOSE OPERON IN ESCHERICHIA COLI. I. PURIFICATION AND CHARACTERIZATION OF URIDINE DIPHOSPHOGALACTOSE 4-EPIMERASE.
J Biol Chem. 1964 Aug;239:2469-81
PMID: 14235524
-
A quantitative assay for DNA-RNA hybrids with DNA immobilized on a membrane.
J Mol Biol. 1965 Jul;12(3):829-42
PMID: 4955314
-
Galactose 1-phosphate uridylyltransferase of Escherichia coli. II. Further purification and characterization.
J Biol Chem. 1967 May 25;242(10):2362-8
PMID: 5338129
-
A partial deletion map of the galactose operon in E. coli K12.
Genet Res. 1967 Aug;10(1):107-16
PMID: 4863202
-
Measurement of the unstable RNA in exponentially growing cultures of Bacillus subtilis and Escherichia coli.
J Mol Biol. 1968 Jan 28;31(2):237-66
PMID: 4965769
-
Sequential appearance of the galactose enzymes in E. coli.
Mol Gen Genet. 1967;100(2):210-5
PMID: 4869992
-
Translation of the tryptophan messenger RNA of Escherichia coli.
Proc Natl Acad Sci U S A. 1968 Aug;60(4):1428-35
PMID: 4877272
-
Sequential derepression and repression of the tryptophan operon in E. coli.
Nature. 1968 Nov 2;220(5166):441-4
PMID: 4879599
-
Negative control of the galactose operon in E. coli.
Mol Gen Genet. 1968;102(1):79-88
PMID: 4883532