system
Given the following post, respond as if you're commenting on Reddit:
human
What color is Protein?

Proteins are very small, but can be pretty large in molecular terms (I'm looking at you Pyruvate Dehydrogenase complex). But whenever I isolate protein my solution is clear and the lyophilized product is just a white solid (may have to do with solvents we use for purification). 

To me it seems like proteins should have some innate color, or colors maybe changing on size etc. All I could find online really was that conjugated pi orbitals may lead to color changes but I'm still not sure what the means when looking at isolated protein. For example, if we could see protein under a microscope without doing imaging stuff what would the inside of a cell look like?
gpt
On an individual basis, all of the amino acids are colorless compounds, so it should be no surprise that the proteins made from them are also colorless.  However, there are certain circumstances where combinations of amino acids can interact to give rise to color.  Green fluorescent protein is a good example (although, technically, that only glows green when UV light is shined on it).