Table 3. Spearman correlation between MGS essentiality and node connectivity^a.

Object	rho	p-value
Essentiality ~ node connectivity	0.211	0.008198
Essentiality ~ average in-degree	−0.274	0.000512
Essentiality ~ average out-degree	−0.281	0.000369
Essentiality ~ average degree	−0.278	0.000424

^aMGS essentiality is represented by cluster size; node connectivity is represented by the number of reactions associated with a gene; average in-degree is represented by the number of reactants divided by that of reactions associated with a gene; average out-degree is represented by the number of products divided by that of reactions associated with a gene; average degree is represented by the number of metabolites divided by that of reactions associated with a gene.