Monogamy is not for the faint of heart, at least if you’re a protein.
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Scientists examining the convoluted network of a cell’s metabolic reactions find that loyal proteins — those that stick to one main task — have important, high-stress jobs. Their promiscuous counterparts, which dabble in various chemical reactions, carry out tasks less crucial to life.
The new work, published in the Aug. 31 Science, examined the activity of enzymes — the proteins that make chemical reactions happen — in the bacterium E. coli. Researchers at the University of California, San Diego and Harvard Medical School used a computer model to analyze the various reactions that allow the bacterium to go about its business.