New pathway for the metabolism of pentitols

Abstract

Certain strains of Lactobacillus casei can grow at the expense of 1 or more pentitols. These microorganisms possess a pentitol phosphate pathway that appears to be analogous to the hexitol phosphate pathway found in many facultatively anaerobic bacteria. Pentitol is transported into the cell by a phosphoenolpyruvate phosphotransferase system that converts it to pentitol phosphate, whereupon a specific dehydrogenase oxidizes the intermediate product to ketopentose phosphate. The ketopentose phosphate is subsequently converted to xylulose-5-P [phosphate] and enters one of the pathways of central metabolism.