[Chimera-users] Need Information

Hi, I am Wisdom, an MSc Bioinformatics student of the University of the Western Cape, South Africa. I wish to understand the meaning of the colouring of the individual amino acids in the sequence window of multiple sequence alignment as per the attached. I one see that all the Rs indicated by the black arrow are all red while the blue arrow has black Rs and orange Gs in the same column. There are other similar coloring all over the alignment. What does each (green, black, blue, orange, purple,red ) colour represent? Thanks Wisdom