TABLE 2.
Enzymes involved in the biosynthesis of polysaccharides in the M. mycoides cluster and putative homologs in M. agalactiae
| Enzyme name or category (reaction)e |
Mycoplasma mycoides cluster gene(s)a |
Mycoplasma agalactiae gene(s)b |
||||
|---|---|---|---|---|---|---|
| M. mycoides subsp. mycoides strain PG1T | M. capricolum subsp. capripneumoniae strain Ambosa | M. mycoides subsp. capri strain PG3T | Strain PG2T | Strain 5632 | Strain 14628 | |
| Pgm (Glc-6P→Glc-1P) | MSC_0829 | MCCP01_0854 | MMC_0730 | MAG4650 | MAGa5120 | MAGb_1060 |
| GalU (Glc-1P→UDP-Glc) | MSC_0110, MSC_0990 | MCCP01_0082 | MMC_6550 | MAG4580 | MAGa4810 | MAGb_0980 |
| GalE (UDP-Glc↔UDP-Galp) | MSC_0971, MSC_0978 | ND | ND | ND | ND | ND |
| Glf (UDP-Galp→UDP-Galf) | MSC_0984 | ND | ND | ND | ND | ND |
| Glycosyltransferases predicted as synthasesc (polymerization and secretion of polysaccharides) | MSC_0108 (449 aa/4 TMDs) | MCCP01_0081 (524 aa/7 TMDs) | MMC_0120 (514 aa/7 TMDs), MMC_6560 (523 aa/7 TMDs) | MAG4860d (244 aa/2 TMDs) | MAGa5320d (96) (351 aa/2 TMDs) | MAGb_1260 (96) (533 aa/7 TMDs) |
| Other glycosyltransferases | MSC_0109, MSC_0771 | MCCP01_0815 | MMC_1050 | MAG0570, MAG3010 | MAGa0600 (98), MAGa3400 (97) | MAGb_4980 (90), MAGb_7470 (97) |
Biosynthetic pathways were predicted by Bertin et al. (12, 13). Genes are designated by their locus tags.
Glycosyltransferases in PG2 were predicted using the CAZy database, and homologs in strains 5632 and 14628 were determined by BLASTP analysis using PG2T sequences (identity percentages are indicated in parentheses). aa, amino acids. Some enzymes were not detected (ND) using BLASTP searches.
Polysaccharide synthases were identified in this study by analyzing their secondary structure predicted by TMHMM 2.0 and their similarity with other known synthases using Phyre. The length of the predicted synthases and the number of transmembrane domains (TMDs) are indicated.
Truncated protein.
Pgm, phosphoglucomutase; GalU, glucose-1-phosphate uridylyltransferase; GalE, UDP-glucose 4-epimerase; Glf, UDP-galactofuranose mutase; Glc, glucose; Galp, galactopyranose; Galf, galactofuranose.