pathwayStep

Definition: A step in a pathway. Comment: Multiple interactions may occur in a pathway step, each should be listed in the STEP-INTERACTIONS property. Order relationships between pathway steps may be established with the NEXT-STEP slot. This order may not be temporally meaningful for specific steps, such as for a pathway loop or a reversible reaction, but represents a directed graph of step relationships that can be useful for describing the overall flow of a pathway, as may be useful in a pathway diagram. Example: A metabolic pathway may contain a pathway step composed of one biochemical reaction (BR1) and one catalysis (CAT1) instance, where CAT1 describes the catalysis of BR1.

Source:http://www.biopax.org/release/biopax-level2.owl#pathwayStep