Table 3. Significantly enriched KEGG pathways in the MC metagenomes relative to the CT metagenomes, based on odds ratios (OR) calculated between the copy number of putative gene sequences in the MC and CT metagenomes.

KEGG Pathway	General Processes	Functional Description	MC	CT	ORMC/CT
Cellular Processes
2030	Cell Motility	Bacterial chemotaxis	2257	343	3.7
2040	Cell Motility	Flagella assembly	2458	518	2.7
Environmental Information Processing
2020	Signal Transduction	Two-component system	8185	2297	2.1
3070	Membrane Transport	Bacterial secretion system	3063	1264	1.4
Metabolism
0480	Metabolism of Other Amino Acids	Glutathione metabolism	2254	954	1.3
0540	Glycan Biosynthesis and Metabolism	Lipopolysaccharide biosynthesis	1822	539	1.9
0550	Glycan Biosynthesis and Metabolism	Peptidoglycan biosynthesis	2815	1279	1.2
0564	Lipid Metabolism	Glycerophospholipid metabolism	1542	613	1.4
0680	Energy Metabolism	Methane metabolism	3805	1807	1.2
0780	Metabolism of Cofactors and Vitamins	Biotin metabolism	469	136	1.9
0860	Metabolism of Cofactors and Vitamins	Porphyrin and chlorophyll metabolism	3160	1122	1.6
0910	Energy Metabolism	Nitrogen metabolism	2900	184	1.3
0920	Energy Metabolism	Sulfur metabolism	1379	535	1.4
0980	Xenobiotics Biodegradation	Xenobiotics metabolism by Cytochrom P450	342	124	1.5