sul_ex -> sul
eth_ex -> eth
A3c + sul -> PPi + aps
oxy_ex -> oxy
oxy -> oxy_ex
A3c + aps -> A2c + pap
3*N2 + pap -> 3*N1 + hyd
hyd + oah -> cys
cys -> 0
2*N1 + eth -> 2*N2 + aco
aco -> oah
hyd -> 0
oah -> 0
S2 + aco -> S1
4*N1 + S1 -> 4*N2 + S2
C1 + Hm + N2 -> C2 + Ho + N1
C2 + oxy -> C1 + H2O
A2c + A3m -> A2m + A3c
A2m + Ho -> A3m + Hm
Ho -> Hm
A3c -> A2c