Occurrence of d-tagatose-6-phosphate pathway of d-galactose metabolism among staphylococci

The Origin of Human Milk Bacteria: Is There a Bacterial Entero-Mammary Pathway during Late Pregnancy and Lactation?

“…For example, some staphylococci (e.g., S. epidermidis and Staphylococcus aureus) are typically associated with catheters and indwelling medical devices in hospital settings, and mammary glands develop an extraordinary complex net of "catheter-like" ducts during late pregnancy and lactation, providing an excellent physical support to these microorganisms. Second, lactose and galactose metabolism of staphylococci is highly efficient through the D-tagatose-6-phosphate pathway (29). Finally, these bacteria readily metabolize human milk oligosaccharides (30).…”

Chemical and molecular classification of staphylococci

“…Galactose and lactose are usually degraded via the so-called Leloir pathway whereby galactose-1-phosphate is epimerized to glucose-1-phosphate. However, in some staphylococci as well as in some streptococci a different pathway is found (Bisett & Anderson 1973;Schleifer et al 1978), the so-called tagatose-6-phosphate pathway. Galactose-6-phosphate is isomerized to tagatose-6-phosphate which is converted to tagatose-1,6-diphosphate and then cleaved to triose-phosphate.…”

Phosphoenolpyruvate:carbohydrate phosphotransferase system of bacteria.

“…In most gram-positive bacteria, however, and in a few plasmidcontaining strains of the family Enterobacteriaceae, these carbohydrates are taken up and phosphorylated by specific enzymes II. PTS-dependent metabolism of lactose and galactose invariably yields galactose 6-phosphate as an intermediate which, after its isomerization to tagatose 6-phosphate, is metabolized further via the tagatose 6phosphate pathway (29,30,49,342). Part of this pathway is also involved in the degradation of galactitol and is present in all strains of the enteric bacteria tested thus far (193).…”