| Role | Gene | Name | |
| 6-phospho-beta-galactosidase (EC 3.2.1.85) | No genes | | |
| Aldose 1-epimerase (EC 5.1.3.3) | MPMX19_04075 | | |
| | MPMX19_06214 | | |
| Alpha-galactosidase (EC 3.2.1.22) | MPMX19_05936 | | |
| Arabinogalactan endo-1,4-beta-galactosidase (EC 3.2.1.89) | No genes | | |
| Beta-galactosidase (EC 3.2.1.23) | MPMX19_04935 | | |
| | MPMX19_05712 | | |
| | MPMX19_05938 | | |
| Beta-galactosidase (EC 3.2.1.23), LacA family | No genes | | |
| Beta-galactosidase (EC 3.2.1.23), LacZ family | No genes | | |
| Beta-galactosidase large subunit (EC 3.2.1.23) | No genes | | |
| Beta-galactosidase small subunit (EC 3.2.1.23) | No genes | | |
| Galactokinase (EC 2.7.1.6) | No genes | | |
| Galactose operon repressor, GalR-LacI family of transcriptional regulators | No genes | | |
| Galactose permease | No genes | | |
| Galactose-1-phosphate uridylyltransferase (EC 2.7.7.10) | No genes | | |
| Galactose-6-phosphate isomerase, LacA subunit (EC 5.3.1.26) | No genes | | |
| Galactose-6-phosphate isomerase, LacB subunit (EC 5.3.1.26) | No genes | | |
| Galactose/methyl galactoside ABC transport system, ATP-binding protein MglA (EC 3.6.3.17) | No genes | | |
| Galactose/methyl galactoside ABC transport system, D-galactose-binding periplasmic protein MglB (TC 3.A.1.2.3) | No genes | | |
| Galactose/methyl galactoside ABC transport system, permease protein MglC (TC 3.A.1.2.3) | No genes | | |
| Lactose and galactose permease, GPH translocator family | No genes | | |
| Lactose permease | No genes | | |
| Lactose phosphotransferase system repressor | No genes | | |
| Mgl repressor and galactose ultrainduction factor GalS, HTH-type transcriptional regulator | No genes | | |
| PTS system, galactose-specific IIA component (EC 2.7.1.69) | No genes | | |
| PTS system, galactose-specific IIB component (EC 2.7.1.69) | No genes | | |
| PTS system, galactose-specific IIC component (EC 2.7.1.69) | No genes | | |
| PTS system, lactose-specific IIA component (EC 2.7.1.69) | No genes | | |
| PTS system, lactose-specific IIB component (EC 2.7.1.69) | No genes | | |
| PTS system, lactose-specific IIC component (EC 2.7.1.69) | No genes | | |
| Predicted galactoside ABC transporter type II, permease protein 1 | No genes | | |
| Predicted galactoside ABC transporter type II, permease protein 2 | No genes | | |
| Predicted galactoside ABC transporter type II, sugar-binding protein | No genes | | |
| Predicted galactoside ABC transporter, ATP-binding protein 1 | No genes | | |
| Predicted galactoside ABC transporter, ATP-binding protein 2 | No genes | | |
| Predicted galactoside ABC transporter, permease protein 1 | No genes | | |
| Predicted galactoside ABC transporter, permease protein 2 | No genes | | |
| Predicted galactoside ABC transporter, sugar-binding protein | No genes | | |
| Predicted regulator of galactoside utilization, LacI family | No genes | | |
| Tagatose 1,6-bisphosphate aldolase (EC 4.1.2.40) | No genes | | |
| Tagatose-6-phosphate kinase (EC 2.7.1.144) | No genes | | |
| Transcriptional repressor of the lac operon | No genes | | |
| UDP-glucose 4-epimerase (EC 5.1.3.2) | MPMX19_00823 | | |
| | MPMX19_01802 | | |
| | MPMX19_01806 | | |
| | MPMX19_03144 | | |
| | MPMX19_04151 | | |
| | MPMX19_04578 | | |
| | MPMX19_05054 | | |
| | MPMX19_06619 | | |
| | MPMX19_06729 | | |