|
type |
Journal Article |
authors |
Zhang L, Chen J, Chen N, Sun J, Zheng P, Ma Y. |
title |
Cloning of two 5-aminolevulinic acid synthase isozymes HemA and HemO from Rhodopseudomonas palustris with favorable characteristics for 5-aminolevulinic acid production |
journal |
Biotechnol Lett |
Activity |
2.3.1.37 |
Family |
2.3.1.37 |
sel |
selected |
ui |
23338702 |
year |
(2013) |
volume |
35 |
number |
5 |
pages |
763-8 |
| |
abstract |
5-Aminolevulinic acid (ALA) synthase (ALAS) HemA from non-sulfur photosynthetic bacteria has been used for the ALA bioproduction, whereas the isoenzyme HemT/HemO is less studied and not used for ALA production. Two ALAS-encoding genes, hemA and hemO from Rhodopseudomonas palustris were cloned, purified and characterized. The ALASs had very high specific activity, 3.6 and 2.7 U/mg, respectively, and strong affinity for one of its substrates, succinyl-CoA, K m with values of 11 and 4.4 μM, respectively. HemO retained up to 60 % maximum activity within a broad range of concentrations of hemin, while HemA kept only 20 % at 10 μM hemin. Escherichia coli overexpressing HemA or HemO produced 5.7 and 6.3 g ALA/l, respectively, in a 5 l bioreactor. |
last changed |
2017/10/24 09:26 |
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