John Ralph
University of Wisconsin-Madison
H-index: 132
North America-United States
Description
John Ralph, With an exceptional h-index of 132 and a recent h-index of 81 (since 2020), a distinguished researcher at University of Wisconsin-Madison, specializes in the field of Lignin chemistry, plant cell wall biosynthesis, NMR, synthesis.
His recent articles reflect a diverse array of research interests and contributions to the field:
Disruption of p-coumaroyl-CoA:monolignol transferases in rice drastically alters lignin composition
Structural and chemical changes in hardwood cell walls during early stages of flash pyrolysis
Author Correction: The flying spider-monkey tree fern genome provides insights into fern evolution and arborescence
Production of biomass‐derived p‐hydroxybenzamide: Synthesis of p‐aminophenol and paracetamol
Hydroxycinnamaldehyde-derived benzofuran components in lignins
The flying spider-monkey tree fern genome provides insights into fern evolution and arborescence (vol 8, pg 500, 2022)
Energy‐Resolved Mass Spectrometry as a Tool for Identification of Lignin Depolymerization Products
Lignin deconstruction by anaerobic fungi
Professor Information
University | University of Wisconsin-Madison |
---|---|
Position | Professor of Biochemistry and DOE Great Lakes Bioenergy Research Center |
Citations(all) | 66233 |
Citations(since 2020) | 28314 |
Cited By | 53220 |
hIndex(all) | 132 |
hIndex(since 2020) | 81 |
i10Index(all) | 435 |
i10Index(since 2020) | 357 |
University Profile Page | University of Wisconsin-Madison |
Research & Interests List
Lignin chemistry
plant cell wall biosynthesis
NMR
synthesis
Top articles of John Ralph
Disruption of p-coumaroyl-CoA:monolignol transferases in rice drastically alters lignin composition
Grasses are abundant feedstocks that can supply lignocellulosic biomass for production of cell-wall-derived chemicals. In grass cell walls, lignin is acylated with p-coumarate. These p-coumarate decorations arise from the incorporation of monolignol p-coumarate conjugates during lignification. A previous biochemical study identified a rice (Oryza sativa) BAHD acyltransferase (AT) with p-coumaroyl-CoA:monolignol transferase (PMT) activity in vitro. In this study, we determined that that enzyme, which we name OsPMT1 (also known as OsAT4), and the closely related OsPMT2 (OsAT3) harbor similar catalytic activity toward monolignols. We generated rice mutants deficient in either or both OsPMT1 and OsPMT2 by CRISPR/Cas9-mediated mutagenesis and subjected the mutants’ cell walls to analysis using chemical and nuclear magnetic resonance methods. Our results demonstrated that OsPMT1 and OsPMT2 …
Authors
Lydia Pui Ying Lam,Yuki Tobimatsu,Shiro Suzuki,Takuto Tanaka,Senri Yamamoto,Yuri Takeda-Kimura,Yuriko Osakabe,Keishi Osakabe,John Ralph,Laura E Bartley,Toshiaki Umezawa
Journal
Plant Physiology
Published Date
2024/2
Structural and chemical changes in hardwood cell walls during early stages of flash pyrolysis
Volatile products from thermal decomposition of lignocellulosic biomass have been well characterized, but the solid- and liquid-phase reactions during the early stages of decomposition are largely unknown. Here the initial solid-phase biomass thermal deconstruction reactions were analyzed in situ and with high particle heating rates, delineating how these processes occur. A variety of instrumentation was used to quantify the extent and relative rates of deconstruction, demonstrating that biopolymers resist the thermally energetic conditions to differing degrees, even when ensconced in biomass cell walls. Hemicellulose and the more frangible lignin components decompose and volatilize more readily than cellulose, which temporarily enriches biomass with cellulose. These chemical changes manifest in larger cell wall structural and mechanical property transformations. In all, this investigation concludes that these solid-phase reactions strongly influence the production rates of volatile species and will require additional study before these processes can be modeled precisely to improve yields of desired product.
Authors
Jake K Lindstrom,Chad A Peterson,Peter N Ciesielski,John Ralph,Mingjie Chen,Joseph E Jakes,Patrick A Johnston,Sean A Rollag,Robert C Brown
Journal
Frontiers in Energy Research
Published Date
2024/3/6
Author Correction: The flying spider-monkey tree fern genome provides insights into fern evolution and arborescence
In the version of the article initially published, Dipak Khadka, who collected the samples in Nepal, was thanked in the Acknowledgements instead of being listed as an author. His name and affiliation (GoldenGate International College, Tribhuvan University, Battisputali, Kathmandu, Nepal) have been added to the authorship in the HTML and PDF versions of the article.
Authors
Xiong Huang,Wenling Wang,Ting Gong,David Wickell,Li-Yaung Kuo,Xingtan Zhang,Jialong Wen,Hoon Kim,Fachuang Lu,Hansheng Zhao,Song Chen,Hui Li,Wenqi Wu,Changjiang Yu,Su Chen,Wei Fan,Shuai Chen,Xiuqi Bao,Li Li,Dan Zhang,Longyu Jiang,Dipak Khadka,Xiaojing Yan,Zhenyang Liao,Gongke Zhou,Yalong Guo,John Ralph,Ronald R Sederoff,Hairong Wei,Ping Zhu,Fay-Wei Li,Ray Ming,Quanzi Li
Journal
Nature Plants
Published Date
2024
Production of biomass‐derived p‐hydroxybenzamide: Synthesis of p‐aminophenol and paracetamol
As we work to transition the modern society that is based on non‐renewable chemical feedstocks to a post‐modern society built around renewable sources of energy, fuels, and chemicals, there is a need to identify the renewable resources and processes for converting them to platform chemicals. Herein, we explore a strategy for extracting the p‐hydroxybenzoate from biomass feedstocks (e.g., poplar and palm trees) and converting it into a portfolio of commodity chemicals. The targeted bio‐derived product in the first processing stage is p‐hydroxybenzamide produced from p‐hydroxybenzoate esters found in the plant. In the second stage a continuous reaction process converts the p‐hydroxybenzamide to p‐aminophenol via the Hofmann rearrangement and recovers the unreacted p‐hydroxybenzamide. In the third stage the p‐aminophenol can be acetylated to form paracetamol, which is readily isolated by liquid …
Authors
Steven D Karlen,Vitaliy I Timokhin,Canan Sener,Justin K Mobley,Troy Runge,John Ralph
Journal
ChemSusChem
Published Date
2024/3/5
Hydroxycinnamaldehyde-derived benzofuran components in lignins
Lignin is an abundant polymer in plant secondary cell walls. Prototypical lignins derive from the polymerization of monolignols (hydroxycinnamyl alcohols), mainly coniferyl and sinapyl alcohol, via combinatorial radical coupling reactions and primarily via the endwise coupling of a monomer with the phenolic end of the growing polymer. Hydroxycinnamaldehyde units have long been recognized as minor components of lignins. In plants deficient in cinnamyl alcohol dehydrogenase, the last enzyme in the monolignol biosynthesis pathway that reduces hydroxycinnamaldehydes to monolignols, chain-incorporated aldehyde unit levels are elevated. The nature and relative levels of aldehyde components in lignins can be determined from their distinct and dispersed correlations in 2D 1H–13C-correlated nuclear magnetic resonance (NMR) spectra. We recently became aware of aldehyde NMR peaks, well resolved …
Authors
Koichi Yoshioka,Hoon Kim,Fachuang Lu,Nette De Ridder,Ruben Vanholme,Shinya Kajita,Wout Boerjan,John Ralph
Journal
Plant Physiology
Published Date
2024/3
The flying spider-monkey tree fern genome provides insights into fern evolution and arborescence (vol 8, pg 500, 2022)
To date, little is known about the evolution of fern genomes, with only two small genomes published from the heterosporous Salviniales. Here we assembled the genome of Alsophila spinulosa, known as the flying spider-monkey tree fern, onto 69 pseudochromosomes. The remarkable preservation of synteny, despite resulting from an ancient whole-genome duplication over 100 million years ago, is unprecedented in plants and probably speaks to the uniqueness of tree ferns. Our detailed investigations into stem anatomy and lignin biosynthesis shed new light on the evolution of stem formation in tree ferns. We identified a phenolic compound, alsophilin, that is abundant in xylem, and we provided the molecular basis for its biosynthesis. Finally, analysis of demographic history revealed two genetic bottlenecks, resulting in rapid demographic declines of A. spinulosa. The A. spinulosa genome fills a crucial gap in the …
Authors
Xiong Huang,Wenling Wang,Ting Gong,David Wickell,Li-Yaung Kuo,Xingtan Zhang,Jialong Wen,Hoon Kim,Fachuang Lu,Hansheng Zhao,Song Chen,Hui Li,Wenqi Wu,Changjiang Yu,Su Chen,Wei Fan,Shuai Chen,Xiuqi Bao,Li Li,Dan Zhang,Longyu Jiang,Xiaojing Yan,Zhenyang Liao,Gongke Zhou,Yalong Guo,John Ralph,Ronald R Sederoff,Hairong Wei,Ping Zhu,Fay-Wei Li,Ray Ming,Quanzi Li
Journal
Nature Plants
Published Date
2022/5
Energy‐Resolved Mass Spectrometry as a Tool for Identification of Lignin Depolymerization Products
Lignin is the largest source of bio‐based aromatic compounds in nature, and its valorization is essential to the sustainability of lignocellulosic biorefining. Characterizing lignin‐derived compounds remains challenging due to the heterogeneity of this biopolymer. Tandem mass spectrometry is a promising tool for lignin structural analytics, as fragmentation patterns of model compounds can be extrapolated to identify characteristic moieties in complex samples. This work extended previous resonance excitation‐type collision‐induced dissociation (CID) methods that identified lignin oligomers containing β–O–4, β–5, and β–β bonds, to also identify characteristics of 5–5, β–1, and 4–O–5 dimers, enabled by quadrupole time‐of‐flight (QTOF) CID with energy‐resolved mass spectrometry (ERMS). Overall, QTOF‐ERMS offers in‐depth structural information and could ultimately contribute to tools for high‐throughput lignin …
Authors
Xueming Dong,Heather B Mayes,Kris Morreel,Rui Katahira,Yanding Li,John Ralph,Brenna A Black,Gregg T Beckham
Journal
ChemSusChem
Published Date
2023/1/9
Lignin deconstruction by anaerobic fungi
Lignocellulose forms plant cell walls, and its three constituent polymers, cellulose, hemicellulose and lignin, represent the largest renewable organic carbon pool in the terrestrial biosphere. Insights into biological lignocellulose deconstruction inform understandings of global carbon sequestration dynamics and provide inspiration for biotechnologies seeking to address the current climate crisis by producing renewable chemicals from plant biomass. Organisms in diverse environments disassemble lignocellulose, and carbohydrate degradation processes are well defined, but biological lignin deconstruction is described only in aerobic systems. It is currently unclear whether anaerobic lignin deconstruction is impossible because of biochemical constraints or, alternatively, has not yet been measured. We applied whole cell-wall nuclear magnetic resonance, gel-permeation chromatography and transcriptome …
Authors
Thomas S Lankiewicz,Hemant Choudhary,Yu Gao,Bashar Amer,Stephen P Lillington,Patrick A Leggieri,Jennifer L Brown,Candice L Swift,Anna Lipzen,Hyunsoo Na,Mojgan Amirebrahimi,Michael K Theodorou,Edward EK Baidoo,Kerrie Barry,Igor V Grigoriev,Vitaliy I Timokhin,John Gladden,Seema Singh,Jenny C Mortimer,John Ralph,Blake A Simmons,Steven W Singer,Michelle A O’Malley
Journal
Nature microbiology
Published Date
2023/4
Professor FAQs
What is John Ralph's h-index at University of Wisconsin-Madison?
The h-index of John Ralph has been 81 since 2020 and 132 in total.
What are John Ralph's top articles?
The articles with the titles of
Disruption of p-coumaroyl-CoA:monolignol transferases in rice drastically alters lignin composition
Structural and chemical changes in hardwood cell walls during early stages of flash pyrolysis
Author Correction: The flying spider-monkey tree fern genome provides insights into fern evolution and arborescence
Production of biomass‐derived p‐hydroxybenzamide: Synthesis of p‐aminophenol and paracetamol
Hydroxycinnamaldehyde-derived benzofuran components in lignins
The flying spider-monkey tree fern genome provides insights into fern evolution and arborescence (vol 8, pg 500, 2022)
Energy‐Resolved Mass Spectrometry as a Tool for Identification of Lignin Depolymerization Products
Lignin deconstruction by anaerobic fungi
...
are the top articles of John Ralph at University of Wisconsin-Madison.
What are John Ralph's research interests?
The research interests of John Ralph are: Lignin chemistry, plant cell wall biosynthesis, NMR, synthesis
What is John Ralph's total number of citations?
John Ralph has 66,233 citations in total.
What are the co-authors of John Ralph?
The co-authors of John Ralph are Clint Chapple, Xuejun Pan, Jing-Ke Weng.