title: Proline transport by tsetse fly Glossina morsitans flight muscle mitochondria.
abstract: 1. Proline accumulation by tsetse fly Glossina morsitans flight muscle mitochondria was studied in vitro by the swelling technique and direct measurement of (U-14C) proline. 2. Proline transport was inhibited by the uncharged liposoluble -SH reagent, N-ethylmaleimide but not by ionic reagent, mersalyl, suggesting that the -SH groups involved in the transport of proline are located in a hydrophobic part of the membrane or on the matrix side of the membrane. 3. The kinetic study of proline accumulation revealed saturation kinetics and a high temperature dependence. It gave a Km of 85 microM and a Vmax of 962 pmol/min/mg protein and an activation energy (Ea) of 11 kcal/mol. 4. Certain other amino acids (L-valine, L-alanine, L-methionine, L-phenylalanine, L-tryptophan and L-hydroxyproline) significantly stimulated proline uptake. 5. These observations indicate that tsetse fly Glossina morsitans flight muscle mitochondria contain a proline transport mechanism.
authors.affiliation: Department of Biochemistry, College of Health Sciences, University of Nairobi, Kenya, Africa.
authors.forename: E N
authors.initials: EN
authors.lastname: Njagi
authors.forename: N K
authors.initials: NK
authors.lastname: Olembo
authors.forename: D J
authors.initials: DJ
authors.lastname: Pearson
mesh_terms: D000244:Adenosine Diphosphate / Q000378:metabolism; D000596:Amino Acids / Q000494:pharmacology; D000818:Animals; D001693:Biological Transport, Active / Q000187:drug effects; D004734:Energy Metabolism; D005426:Flight, Animal / Q000502:physiology; D007700:Kinetics; D008297:Male; D008931:Mitochondria, Muscle / Q000378:metabolism*; D010101:Oxygen Consumption; D011392:Proline / Q000378:metabolism* / Q000494:pharmacology; D013696:Temperature; D014370:Tsetse Flies / Q000378:metabolism*
chemical_list: D000596:Amino Acids; D000244:Adenosine Diphosphate; D011392:Proline