Nitrogenase Defender

Protect the nitrogenase enzyme from oxygen molecules. Cyanobacteria must defend their nitrogen-fixing machinery — and so must you!

• 1.Click or tap to place shields around the nitrogenase enzyme.
• 2.Block incoming oxygen molecules before they reach the enzyme.
• 3.Survive increasingly difficult waves of oxygen attacks.
• 4.Learn how real cyanobacteria use heterocysts and other strategies to protect nitrogenase.