|
type |
Journal Article |
authors |
Tyagi, R. K.; Datta, K. |
title |
In vitro translocation of L-alanine:4,5-dioxovalerate transaminase into rat kidney mitochondria |
journal |
J Biochem (Tokyo) |
Activity |
2.6.1.43 |
ui |
93340101 |
year |
(1993) |
volume |
113 |
number |
5 |
pages |
557-62. |
| |
keywords |
Amino Acids/analysis |
abstract |
A specific rabbit antibody was prepared against rat kidney mitochondrial L-alanine: 4,5-dioxovalerate transaminase, which is one of the two enzymes catalyzing the synthesis of delta-aminolevulinic acid in the heme biosynthetic pathway. Total polyadenylated RNA isolated from rat kidney was translated in vitro using rabbit reticulocyte cell-free translation system, and L-alanine:4,5- dioxovalerate transaminase was estimated by indirect immunoprecipitation to represent 0.85% of the total translation product. When the total in vitro translated product was incubated with homologous kidney mitochondria, 59% of the [35S]methionine labeled enzyme was translocated into the mitochondria where it was no longer accessible to externally added protease. In relation to total protein translocation, the translocation of L-alanine:4,5-dioxovalerate transaminase remained unaltered by addition of hemin up to 50 microM. These results show that, unlike the other enzyme of the heme biosynthetic pathway (delta-aminolevulinic acid synthetase), this enzyme is not under tight control by heme, but nonetheless, functions as an important source to maintain a housekeeping level of delta- aminolevulinic acid. |
last changed |
2002/11/12 16:17 |
|