Abstract:
:The rate of derepressed synthesis of a membrane protein required for lactose transport (M protein) by Escherichia coli is increased in response to increased gene dosage to the same extent as the rates of synthesis of beta-galactosidase and galactoside acetylase. However, elevated gene dosage does not increase beta-galactoside transport to the same extent that it increases synthesis of M protein and of the soluble proteins of the lac operon. Though the factor or factors other than M protein which limit induction of the transport system at high levels of lac operon expression have not been identified, studies with Escherichia coli mutants blocked in the synthesis of unsaturated fatty acids indicate that unsaturated fatty acids must be supplied during the course of induction of the lac operon to permit synthesis of a functional lactose transport system, but not of beta-galactosidase or galactoside acetylase.
journal_name
Proc Natl Acad Sci U S Aauthors
Fox CFdoi
10.1073/pnas.63.3.850subject
Has Abstractpub_date
1969-07-01 00:00:00pages
850-5issue
3eissn
0027-8424issn
1091-6490journal_volume
63pub_type
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