What is the difference between recombinant and purified proteins?

Recombinant proteins are produced by genetically engineering organisms, such as bacteria or yeast, to express a specific protein that may not be naturally abundant or easily extracted. In contrast, purified proteins are those that have been isolated from natural sources or biological systems and have undergone processes to remove contaminants and separate them from other cellular components. Essentially, recombinant proteins are synthesized through biotechnology, while purified proteins derive from natural sources and are refined for use.