|
type |
Journal Article |
authors |
Miyamoto T, Katane M, Saitoh Y, Sekine M, Homma H |
title |
Elucidation of the D-lysine biosynthetic pathway in the hyperthermophile Thermotoga maritima |
journal |
FEBS J |
Activity |
5.1.1.5 |
Family |
5.1.1.5.c |
sel |
selected |
ui |
30548096 |
year |
(2019) |
volume |
286 |
number |
3 |
pages |
601-614 |
| |
keywords |
Thermotoga maritima ; D-amino acid; D-lysine; amino acid racemase; diaminopimelate epimerase |
abstract |
Various D-amino acids are involved in peptidoglycan and biofilm metabolism in bacteria, suggesting that these compounds are necessary for successful adaptation to environmental changes. In addition to the conventional D-alanine (D-Ala) and D-glutamate, the peptidoglycan of the hyperthermophilic bacterium Thermotoga maritima contains both L-lysine (L-Lys) and D-Lys, but not meso-diaminopimelate (meso-Dpm). D-Lys is an uncommon component of peptidoglycan, and its biosynthetic pathway remains unclear. In this study, we identified and characterised a novel Lys racemase (TM1597) and Dpm epimerase (TM1522) associated with the D-Lys biosynthetic pathway in T. maritima. The Lys racemase had a dimeric structure containing pyridoxal 5'-phosphate as a cofactor. Among the amino acids, it exhibited the highest racemase activity toward D- and L-Lys, and also had relatively high activity toward D- and L-enantiomers of ornithine and Ala. The Dpm epimerase had the highest epimerisation activity toward LL- and meso-Dpm, and also measurably racemised certain amino acids, including Lys. These results suggest that Lys racemase contributes to production of D-Lys and D-Ala for use as peptidoglycan components, and that Dpm epimerase converts LL-Dpm to meso-Dpm, a precursor in the L-Lys biosynthetic pathway. This article is protected by copyright. |
fulltext |
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last changed |
2019/03/12 09:48 |
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