pHBMT1, a BAHD-family monolignol acyltransferase, mediates lignin acylation in poplar.
Plant Physiol
; 188(2): 1014-1027, 2022 02 04.
Article
en En
| MEDLINE
| ID: mdl-34977949
ABSTRACT
Poplar (Populus) lignin is naturally acylated with p-hydroxybenzoate ester moieties. However, the enzyme(s) involved in the biosynthesis of the monolignol-p-hydroxybenzoates have remained largely unknown. Here, we performed an in vitro screen of the Populus trichocarpa BAHD acyltransferase superfamily (116 genes) using a wheatgerm cell-free translation system and found five enzymes capable of producing monolignol-p-hydroxybenzoates. We then compared the transcript abundance of the five corresponding genes with p-hydroxybenzoate concentrations using naturally occurring unrelated genotypes of P. trichocarpa and revealed a positive correlation between the expression of p-hydroxybenzoyl-CoA monolig-nol transferase (pHBMT1, Potri.001G448000) and p-hydroxybenzoate levels. To test whether pHBMT1 is responsible for the biosynthesis of monolignol-p-hydroxybenzoates, we overexpressed pHBMT1 in hybrid poplar (Populus alba × P. grandidentata) (35SpHBMT1 and C4HpHBMT1). Using three complementary analytical methods, we showed that there was an increase in soluble monolignol-p-hydroxybenzoates and cell-wall-bound monolignol-p-hydroxybenzoates in the poplar transgenics. As these pendent groups are ester-linked, saponification releases p-hydroxybenzoate, a precursor to parabens that are used in pharmaceuticals and cosmetics. This identified gene could therefore be used to engineer lignocellulosic biomass with increased value for emerging biorefinery strategies.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Acilación
/
Aciltransferasas
/
Populus
/
Lignina
Idioma:
En
Revista:
Plant Physiol
Año:
2022
Tipo del documento:
Article
País de afiliación:
Canadá