The color distinction of the stems in this example is not important because both stems are the same length and both stems are less than 10 bps. [[[[[[[[[[.) ))))))))))))) . [.) ))))))))))))) . and also known as an ABACBC pseudoknot. (f) The structure shown in bracket notation. (g) A pseudoknot. The difference between (c) and (g) is that the linkage stem is shorter than 9 contiguous bps. (h) The same structure in bracket notation. Figure S5c shows a knot and the corresponding bracket structure is shown below in Fig. S5d .