Developmental changes in lignin composition are driven by both monolignol supply and laccase specificity

Zhuo, Chunliu; Wang, Xin; Docampo-Palacios, Maite; Sanders, Brian C.; Engle, Nancy L.; Tschaplinski, Timothy J.; Hendry, John I.; Maranas, Costas D.; Chen, Fang; Dixon, Richard A.

doi:10.1126/sciadv.abm8145

DOE OSTI · 1870229

Developmental changes in lignin composition are driven by both monolignol supply and laccase specificity

Zhuo, Chunliu·Wang, Xin·Docampo-Palacios, Maite·Sanders, Brian C.·Engle, Nancy L.·Tschaplinski, Timothy J.·Hendry, John I.·Maranas, Costas D.·Chen, Fang·Dixon, Richard A.

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Abstract

The factors controlling lignin composition remain unclear. Catechyl (C)–lignin is a homopolymer of caffeyl alcohol with unique properties as a biomaterial and precursor of industrial chemicals. The lignin synthesized in the seed coat of Cleome hassleriana switches from guaiacyl (G)– to C-lignin at around 12 to 14 days after pollination (DAP), associated with a rerouting of the monolignol pathway. Lack of synthesis of caffeyl alcohol limits C-lignin formation before around 12 DAP, but coniferyl alcohol is still synthesized and highly accumulated after 14 DAP. We propose a model in which, during C-lignin biosynthesis, caffeyl alcohol noncompetitively inhibits oxidation of coniferyl alcohol by cell wall laccases, a process that might limit movement of coniferyl alcohol to the apoplast. Developmental changes in both substrate availability and laccase specificity together account for the metabolic fates of G- and C-monolignols in the Cleome seed coat.

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Zhuo, Chunliu, Wang, Xin, Docampo-Palacios, Maite, Sanders, Brian C., Engle, Nancy L., Tschaplinski, Timothy J., Hendry, John I., Maranas, Costas D., Chen, Fang, Dixon, Richard A.. 2022-03-11. Developmental changes in lignin composition are driven by both monolignol supply and laccase specificity. https://doi.org/10.1126/sciadv.abm8145

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