Figure 3.

Topology of knotted rings formed upon topological equilibration of 8 modelled chromatin rings. Knot types of all 8 rings forming a system presented in Figure 4. Alexander–Briggs notation of knots uses two numbers to indicate the knot type. The first number written in normal font indicates the minimal number of crossings of a given knot and the second number written as a subscript indicates the tabular position of this knot among the knots with the same minimal crossing number. So for example, 9₁₁ indicates a knot that in tables of knots is placed at 11th position among knots which minimal crossing number is 9. The # sign indicates that a knot is formed by a composition or merging together of simpler (prime) knots that are listed as its components. For prime knots with a large number of minimal crossings, e.g., 12, as is the case of ring 4, the knots are additionally divided into these with alternating pattern of crossings (indicated as a) and with nonalternating pattern of crossings (indicated as n). Standard tables of knots do not include knots with more than 12 crossings and we indicate these knots as unclassified.