Pseudo amino acid composition is like counting different colored candies in a bag, but instead of candies, we count the building blocks that make up proteins called amino acids.
There are 20 different types, and each protein is made of a combination of these amino acids, kind of like a colorful necklace made of different colored beads. Scientists use pseudo amino acid composition to describe and compare the differences in the "necklaces" (proteins) found in different organisms, tissues or cells.
Instead of counting the actual number of each type of amino acid, scientists use a formula to calculate the frequency or percentage of each amino acid in a protein sequence. This helps them to identify patterns or similarities in the way proteins are put together.
So, if we have a protein with a sequence of 100 amino acids and the formula tells us that 30 of them are glycine (a green bead), we can say that the pseudo amino acid composition of that protein has 30% glycine.
This type of analysis is useful in understanding the structure, function and evolution of proteins and can also help in predicting the properties of newly discovered or engineered proteins.