D-ribulokinase () is an enzyme that catalyzes the chemical reaction
The enzyme characterised from Aerobacter aerogenes converts the pentose sugar, D-ribulose, (shown in its open-chain keto form) to D-ribulose-5-phosphate by transferring a phosphate group from the cofactor, adenosine triphosphate (ATP), which is converted to adenosine diphosphate (ADP). D-ribulose-5-phosphate is one of the end-products of the pentose phosphate pathway. The enzyme is also found in yeast and mammals.
It is a transferases, specifically one transferring phosphorus-containing groups (phosphotransferases) with an alcohol group as acceptor. The systematic name of this enzyme class is ATP:D-ribulose 5-phosphotransferase. It is also called D-ribulokinase (phosphorylating).
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