Utilization of a carbohydrate reserve comprised primarily of mannose by Leishmania donovani.
Promastigotes from late log phase and 3-day stationary phase cultures of Leishmania donovani were collected, washed in buffer, and the cell pellet was treated with boiling KOH. A putative carbohydrate storage material was then precipitated and washed in ethanol/LiBr. This material did not liberate glucose when treated with amyloglucosidase, indicating that it was not glycogen. Acid hydrolysis released a hexose which was identified as mannose by several criteria. Considerably more of this mannan-like carbohydrate is present in cells from 3-day stationary phase than from late log phase cultures, consistent with the ability of 3-day stationary phase cells to survive in non-nutrient buffer and maintain oxygen consumption for longer than log phase cells. The amount of this mannan-like compound decreased by over 50% during a 3-h incubation in buffer of cells from 3-day stationary phase cultures. The presence of glucose during the incubation prevented the utilization of this carbohydrate, consistent with the possibility that it serves as an energy reserve.
Keegan
F P
FP
Department of Cell Biology, Duke University Medical Center, Durham, NC 27710.
Blum
J J
JJ
D000818:Animals; D050260:Carbohydrate Metabolism; D005947:Glucose / Q000378:metabolism; D007893:Leishmania donovani / Q000254:growth & development / Q000378:metabolism*; D008351:Mannans / Q000378:metabolism; D008358:Mannose / Q000378:metabolism; D010101:Oxygen Consumption; D011134:Polysaccharides / Q000378:metabolism
D008351:Mannans; D011134:Polysaccharides; D005947:Glucose; D008358:Mannose