A suicide enzyme catalyzes multiple reactions for biotin biosynthesis in cyanobacteria.
Nat Chem Biol
; 16(4): 415-422, 2020 04.
Article
in En
| MEDLINE
| ID: mdl-32042199
ABSTRACT
In biotin biosynthesis, the conversion of pimeloyl intermediates to biotin is catalyzed by a universal set of four enzymes BioF, BioA, BioD and BioB. We found that the gene homologous to bioA, the product of which is involved in the conversion of 8-amino-7-oxononanoate (AON) to 7,8-diaminononanoate (DAN), is missing in the genome of the cyanobacterium Synechocystis sp. PCC 6803. We provide structural and biochemical evidence showing that a novel dehydrogenase, BioU, is involved in biotin biosynthesis and functionally replaces BioA. This enzyme catalyzes three reactions formation of covalent linkage with AON to yield a BioU-DAN conjugate at the ε-amino group of Lys124 of BioU using NAD(P)H, carboxylation of the conjugate to form BioU-DAN-carbamic acid, and release of DAN-carbamic acid using NAD(P)+. In this biosynthetic pathway, BioU is a suicide enzyme that loses the Lys124 amino group after a single round of reaction.
Full text:
1
Database:
MEDLINE
Main subject:
Oxidoreductases
/
Biotin
/
Synechocystis
Language:
En
Year:
2020
Type:
Article