Why is it important to remove aggregates during GFP purification?

Removing aggregates during GFP purification is crucial to ensure the purity and functionality of the GFP. Aggregation can lead to the formation of proteins that are not biologically active or that exhibit altered properties. For GFP, this is particularly important because its fluorescence is an inherent property of its correctly folded structure. If aggregate forms are present, they may not fluoresce or may fluoresce at different wavelengths, making it difficult to evaluate the activity and quality of the purified protein accurately. In essence, a pure sample of GFP, free from aggregates, will allow researchers to accurately assess its biological activity and usefulness in various applications, such as imaging or protein labeling.

While other factors like yield and fluorescence intensity may be important, the primary focus during purification is on obtaining a functional and pure product. This ensures that subsequent experiments using GFP yield reliable and interpretable results.