Premium
Incorporation of Label from Acetate and Laurate into the Mannan of Leishmania donovani via the Glyoxylate Cycle
Author(s) -
KEEGAN FRANK P.,
BLUM J. JOSEPH
Publication year - 1993
Publication title -
journal of eukaryotic microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.067
H-Index - 77
eISSN - 1550-7408
pISSN - 1066-5234
DOI - 10.1111/j.1550-7408.1993.tb04467.x
Subject(s) - mannan , glyoxylate cycle , biochemistry , biology , mannose , lead acetate , enzyme , chemistry , polysaccharide , organic chemistry , toxicity
Leishmania donovani promastigotes in late‐stationary phase incorporated label from [2‐ 14 C]acetate and [1‐ 14 C]laurate into the mannose residues of mannan, thus confirming the presence of a functional glyoxylate bypass in these parasitic protozoa. Isolated, washed calls also incorporated label from [2‐ 14 C]acetate and [1‐ 14 C]laurate into mannan during a 1‐hr incubation in buffer. Glucose had no effect on label incorporation into mannan, but glutamate caused over a four‐fold increase in incorporation from [2‐ 14 C]acetate and a 2.4‐fold increase from [1‐ 14 C]laurate. Staurosporine, a protein kinase inhibitor that inhibits glutamate and alanine oxidation, did not inhibit label incorporation from [2‐ 14 C]acetate into mannan. Hyperosmolality caused about a 33% inhibition of label incorporation into mannan. These results show the glyoxylate cycle and/or the subsequent biosynthetic pathway from fructose‐6‐phosphate to mannan are subject to regulation.