Biology/microbiology
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Question
since the genome of e.coli is inside the cell, how it recognizes the lactose present in the medium?
Hi Aruna: Thanks for your question.
The lactose diffuses into the cell and activates the lac operon. Operons are ways that the cell can respond to its environment. Lactose binds to the lac repressor and induces the enzymes necessary for the metabolism of lactose (a disaccharide).
Here's a link and great movie that explains it all:
http://vcell.ndsu.edu/animations/lacOperon/movie.htm
Hope this helps.
FM Rollwagen, PhD
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Answers by Expert:
Florence M Rollwagen
Expertise
I can answer questions in biology, microbiology and immunology on the undergraduate or graduate level. I can also address medical and health concerns regarding alternative medicine, autoimmune diseases (lupus, MS) liver disease and intestinal problems.
Experience
I have over 20 years experience in research and teaching at the medical/graduate level, and 5 years teaching college biology and microbiology. My expertise is in microbiology and immunology, specifically the biology of cytokines and soluble immune response modifiers. I also carried out original research in blood substitutes and shock/trauma.
Organizations
American Association of Immunologists (AAI)
American Association for the Advancement of Science (AAAS)
Publications
Journal of Experimental Medicine, Journal of Immunology, Cytokine, Shock, Experimental Hematology
Education/Credentials
BS biology 1966
MS biology 1968
PhD immunology 1979
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