Final answer:
A phosphatase enzyme is required in Saccharomyces pombe to remove phosphate groups from Cdk, enabling cell division by activating the Cdk/cyclin complexes.
Step-by-step explanation:
In the yeast Saccharomyces pombe, a phosphatase enzyme is necessary for removing phosphate and activating Cdk so the cell can divide. This enzyme's role is crucial because it reverses the phosphorylation of proteins, which is a key regulatory mechanism in the cell cycle. Cyclin-dependent kinases (Cdks), crucial enzymes in this context, require both association with cyclins and dephosphorylation to become fully active. The phosphatase specifically enables Cdk activation by removing inhibitory phosphate groups that were added by kinases, allowing the Cdk/cyclin complex to phosphorylate other proteins and advance the cell cycle through its various checkpoints. This process is part of a broader regulatory system that relies on kinases and phosphatases to control cell division in eukaryotic organisms, including Saccharomyces pombe.