Phosphoanhydride R1 O

Mixed anhydride R (carboxylic acid and phosphoric acid; also called acyl phosphate)

Phosphoanhydride R1 O

Cells Contain a Universal Set of Small Molecules

Dissolved in the aqueous phase (cytosol) of all cells is a collection of 100 to 200 different small organic molecules (Mr ~100 to ~500), the central metabolites in the major pathways occurring in nearly every cell—the metabolites and pathways that have been conserved throughout the course of evolution. (See Box 1-1 for an explanation of the various ways of referring to molecu lar weight.) This collection of molecules includes the common amino acids, nucleotides, sugars and their phosphorylated derivatives, and a number of mono-, di-, and tricarboxylic acids. The molecules are polar or charged, water soluble, and present in micromolar to millimolar concentrations. They are trapped within the cell because the plasma membrane is impermeable to them—although specific membrane transporters can catalyze the movement of some molecules into and out thioester amido amido

Was this article helpful?

0 0
Lose 10 Pounds Naturally

Lose 10 Pounds Naturally

Studies show obesity may soon overtake tobacco as the leading cause of death in America. Are you ready to drop those extra pounds you've been carrying around? Awesome. Let's start off with a couple positive don't. You don't need to jump on a diet craze and you don't need to start exercising for hours each day.

Get My Free Ebook

Post a comment