Respiration of Leishmania mexicana amastigotes and promastigotes

• Published in: Molecular and biochemical parasitology Vol. 4; no. 1; pp. 39 - 51
• Main Authors: Hart, David T., Vickerman, Keith, Coombs, Graham H.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.01.1981
• Subjects: Amastigotes; Amino Acids - pharmacology; Animals; Antimycin A - pharmacology; Blood; Carbohydrates - pharmacology; Culture Media; Energy metabolism inhibitors; Fatty Acids - pharmacology; Kinetics; Leishmania; Leishmania - growth & development; Leishmania - metabolism; Leishmania mexicana; metabolism; Oxygen Consumption - drug effects; Promastigotes; Protozoa; Respiration; Respiration, Protozoa; PBS; BSA; Promastigotes; FAM; HOMEM; Leishmania; FCS; SHAM; Respiration; Amastigotes; Energy metabolism inhibitors
• ISSN: 0166-6851; 1872-9428
• DOI: 10.1016/0166-6851(81)90027-X

Promastigotes of Leishmania mexicana mexicana recently derived from amastigotes by transformation in vitro respired at a rate (17 nmol O 2/min per 10 8 parasites) 4–5 times higher than that of amastigotes, but when the difference in cell protein content between the two preparations was taken into account the rates were not significantly different (32 nmol O 2/min per mg protein). The respiration of both amastigotes and promastigotes was sensitive to cyanide, azide, antimycin A, 2- n-heptyl-4-hydroxyquinoline- N-oxide and high concentrations of amytal, but insensitive to rotenone and salicylhydroxamic acid, indicating that the two developmental forms possess a similar cytochrome-containing respiratory chain. d-Glucose and non-esterified fatty acids stimulated promastigote respiration and amastigote transformation to promastigotes in vitro; possibly these substances are important exogenous energy substrates for both forms of the parasite. Amino acids (including L-proline) and proteins did not appear to be used as energy substrates. The respiration rate of promastigotes was found to rise significantly upon continued sub-culture in vitro; at the same time cell size and protein content increased.