For modeling purposes, it can be beneficial to unambiguously label a spontaneous reaction, i.e., that no catalyst (no enzyme in particular) is needed for this reaction to proceed. With a specific SBO term for labeling a "spontaneous reaction" as such, automated procedures could leave them out when searching for genetic bases of enzymatic processes or potential genetic regulation. Please create such a new term that modelers can assign to reaction objects in SBML or other formats.
Anonymous
SBO:0000672 term created for Spontaneous reaction.