Explore the Unknown!
For November 17, 2021
Hi WN@TL Fans,
When I was studying botany at UW-Platteville 4.5 decades ago, I first came across several terms or ideas (…is there a difference?) that at the time were short shrifted but since then have grown and blossomed.
One was “epigenetics”. It was mentioned in my genetics textbook. The author rambled on for nearly two full paragraphs. At least one reader was left in a fog as to what it was and as to its significance. Luckily, I don’t remember it being on the test so, as they say in basketball: no harm, no foul. Today, epigenetics is a major slice of the study of patterns of inheritance and of gene expression. Epigeneticists are explaining and exploring and helping us to exploit in a happy way how the environment of parents can influence the traits of their offspring without changing the sequence of DNA.
Another was “lignin”. In several classes—in both botany and biochemistry—I had to learn to draw the structure of glucose, and the structure of the glucose polymer we call starch (aka amylose) with its alpha 1-4 bonds, and the variant amylopectin with its occasional alpha 1-6 bonds that cross linked strands of linear amylose into a network. Then came the twist: if the alternating glucose units in the linear chain were spun 180 degrees, then the glucose units linked together in beta 1-4 bonds, forming cellulose, the stuff that plant cell walls are largely made of.
But plant cell walls, especially in woody plants, have another beast in the feast: lignin. Unlike cellulose, with its repeating units of glucose, lignin was presented to me as a gemush, a biochemical goulash with none of the elan of the creamy flan that is cellulose. I’m not sure how much of the chemystery of lignin was known at the time, but unlike cellulose, I never had to draw a structure of lignin on a test.
Yet if George Gershwin were still here today, he’d probably tune you in to Fascinatin’ Lignin, and Ira Gershwin could lyrically introduce you to the silver medalist of biopolymers, second only to cellulose.
Seeking greater length
early land plants prayed,
“Give us greater strength!”
And plants grew & stayed—
For Evolution had sent in lignin.
Tonight, November 17, we get a chance to unravel the knotty problem of how the class of chemicals called lignins help give the cell walls of plants (and especially trees) such remarkable strength in compression, tension, torsion and shear. John Ralph of Biochemistry and the Wisconsin Energy Institute will drill deep into “Lignins: Intrigue and Controversies Surrounding a Little-Known Major Polymer.”
Description: Lignin, comprising some 15-30% of plant biomass, is arguably the 2nd most abundant terrestrial biopolymer, yet many have never heard of it (although the term ‘lignocellulosics’ is now becoming more widespread). Its structure and biosynthesis are intriguing on many levels, and the theory of lignification has been delightfully controversial. We’ll attempt to highlight some of the intrigue with an emphasis on new findings that offer enhanced opportunities for ‘exploiting’ Nature’s most abundant source of aromatics.
Bio: John Ralph is a Professor of Biochemistry at the University of Wisconsin−Madison and, since 2015, a Distinguished Professor of the Tokyo University of Agriculture and Technology. He obtained his B.Sc. (Hons) in Chemistry at Canterbury University, New Zealand, in 1976, and his Ph.D. in Chemistry/Forestry at the University of Wisconsin−Madison in 1982.
Ralph’s group is recognized for its work on lignin biosynthesis, including delineation of the pathways of monolignol biosynthesis, lignin chemistry, and lignin reactions; particular interest is in the chemical/structural effects of perturbing lignin biosynthesis, and extensions of this work are aimed at redesigning lignins to be more valuable or more readily degraded. The group has developed synthetic methods for biosynthetic products, precursors, intermediates, molecular markers, cell wall model compounds, etc. It has developed methods for solution-state NMR of lignins, including whole-cell-wall methods that require no pre-fractionation of wall components, and chemical/degradative, NMR, and GC-MS combinatorial methods for cell wall cross-linking mechanisms and cell wall structural analysis.
Ralph was elected as a Fellow of the American Association for the Advancement of Science (AAAS) in 2005, is on the Editorial Boards of five international journals, and has been named by the Institute for Scientific Information as one of the 10 most cited authors in the plant and animal sciences every year since 2007.https://biochem.wisc.edu/faculty/ralphhttps://energy.wisc.edu/about/energy-experts/john-ralphhttp://www.glbrc.orghttps://scholar.google.com/citations?user=gkLpFa4AAAAJExplore More:
November 24 is The Night Before Thanksgiving and WN@TL goes dark for our annual excursion over the river and through the wood to Grandfather’s house we go. The song, like the 400th anniversary of the Pilgrim’s first Thanksgiving, is conflicted: in the original, it is a singular wood, not woods; it is to Grandfather’s house, not to Grandmother’s; and it’s about Thanksgiving, not Christmas.
But hay, as we say in America’s Dairyland: close enough.
WN@TL resumes on December 1 with Cody Wenthur speaking on the work of the new Transdisciplinary Center for Research on Psychoactive Substances.
Psychedelics as Catalysts for Change
Description: Psychedelic-assisted psychotherapy approaches using ketamine, MDMA, or psilocybin have shown substantial promise in human trials for the treatment of difficult psychiatric conditions including end-of-life anxiety, treatment resistant depression, and post-traumatic stress disorder. However, there remain many important questions regarding the mechanisms by which these interventions lead to both rapid and lasting behavioral change. Using translational approaches that range from organic synthesis to human studies, the Wenthur Lab is interrogating the role of acute corticosteroid release in the behavioral outcomes following psilocybin administration, assessing polypharmacologic contributions of active metabolites to ketamine’s functional profile, and investigating how differential self-identity and experiential memory contribute to variation in clinical psychedelic studies. In this talk, Dr. Wenthur will discuss the results of these studies to date, highlighting the possible means by which psychedelics may act as molecular change agents, and he will also share insights into how the design and development of these psychedelic research studies have acted to change the trajectory of his own career development thus far.
Bio: Cody Wenthur is an innovative, translational investigator in psychopharmacology who has been on the UW–Madison faculty since 2018. His work is focused on improving our understanding of the basis for beneficial and detrimental effects of opioids, cannabinoids, psychedelics, and other neuroplasticity-inducing approaches in the context of novel therapeutic approaches for promoting and maintaining mental health. His research program has received both basic and clinical grant and fellowship support from NIGMS, NIDA, NIMH, independent foundations, and philanthropic funds. The resulting findings have been published in leading journals such as Nature and PNAS and have yielded the development of first-in-class tool compounds and generated new pharmacologic techniques for the investigation of complex psychoactive mixtures. His scientific research is complemented by his dedicated support of graduate education in neuropharmacology, including active service as the founding director of the Psychedelic Pharmaceutical Investigation Master’s program, and mentorship of PharmD and PhD students in the Pharmaceutical Sciences, Molecular and Cellular Pharmacology, and Neuroscience Training Programs.