pyrophosphate

…enzymatic reaction patterns of the pyrophosphate units (see below Biosynthesis of isoprenoids). Tail-to-tail coupling does not appear to follow expected reaction patterns. Squalene, which has the most notable example of tail-to-tail coupling, is formed by the joining of two equivalents of farnesyl pyrophosphate. In the 1960s the British chemist John…

…split into AMP and inorganic pyrophosphate (PP_i) in the process.

…involved in biosynthesis release inorganic pyrophosphate (PP_i) rather than phosphate (P_i) from ATP, and hence yield AMP rather than ADP. Since inorganic pyrophosphate readily undergoes virtually irreversible hydrolysis to two equivalents of inorganic phosphate (reaction [21a]), the creation of a new bond in the product of synthesis may be accompanied…

…ATP is required, and inorganic pyrophosphate is a product. The aminoacyl–AMP, which remains bound to the enzyme, is transferred to a specific molecule of tRNA in a reaction catalyzed by the same enzyme. AMP is released, and the other product is called aminoacyl–tRNA ([88b]). In E. coli the amino acid…

…presence of elevated levels of pyrophosphate in the synovial fluid. Because pyrophosphate excess can result from cellular injury, pseudogout is often precipitated by trauma, surgery, or severe illness. A deficiency in alkaline phosphatase, the enzyme responsible for breaking down pyrophosphate, is another potential cause of pyrophosphate excess. Other disorders associated…