Justin Cobb jacobb at
Sat Feb 24 23:15:09 EST 2001

"Johannes" <tajojo at> wrote in message
news:20010224182923.25568.qmail at
> Does anybody have information about Feedbackmechanisms concerning enzymes.
> Please, I need your help!


Often times, the product of an enzymatic reaction will act as an allosteric
inhibitor.  However, with some enzymes, the product will act allosterically
as an activator.  Also, the intracellular concentration some enzymes is
controlled at the level of gene expression.  For example, in E.coli, lactase
is not produced in the presence of glucose.  However, in the absence of
glucose, lactate will be produced in these organisms.  This is regulated by
feedback mechanisms involving certain proteins involved in the transcription
of lac genes (although I don't remember exactly how this works in much

Hope this helps.

Justin Cobb

Justin Cobb

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