In addition to the purchase price of a property in France, and the various expenses, commissions, and taxes that that purchase entails, there is a further series of outlays that will arise out of your purchase.
When an enzyme binds its substrate, it forms an enzyme-substrate complex. This complex lowers the activation energy of the reaction and promotes its rapid progression by providing certain ions or chemical groups that actually form covalent bonds with molecules as a necessary step of the reaction process.
In the lock and key model, the substrate and the enzyme's active site are exact matches for each other, similar to puzzle pieces fitting together. Only a single substrate is the 'key' that matches the 'lock' of the active site. Once the enzyme locates the molecule that fits it exactly, the chemical reaction begins.