test
node1
BFO:0000003
occurrent
node1->node1
node3
BFO:0000015
process
node1->node3
node2
BFO:0000001
entity
node2->node1
node4
GO:0003674
molecular_function
node3->node4
node5
GO:0140104
molecular carrier
activity
node4->node5
node6
GO:0140132
iron-sulfur cluster
carrier activity
node5->node6