Homage to Gene Madsen
Eugene Madsen was a microbiologist and toxicologist that provided expert opinion that ultimately allowed my public display of mud --Winogradsky Rothko-- on Cornell's Campus in 2004. In 2005, he responded to my Visualizing Meaning survey of all Cornell faculty with his drawing of the metabolic cycle of life which became incorporated into my 2006 installation called Vector. In 2012, when the Lower Manhattan Cultural Council granted me a residency on Governor's Island in NYC, he provided expert opinion that allowed final permission for me to publicly display Portraits of NY - five paintings featuring mud collected from highly contaminated sites in New York City. It is hard to imagine our fear of microbes even just 2 decades ago, let alone public display of microbes as art. Gene was essential to my display of their transformational beauty. For this reason, I have dedicated this show in his honor.
April 22, 2022, 1pm
In Person: Mann Library Gallery, 2nd floor
On Earthday 2022 there will be a celebratory opening of this show. As part of the opening, there will be a few speakers who will talk about Gene. They include:
- Bill Ghiorse
- Dan Buckley
- Johannes Lehmann
- if you are unable to attend physically, you may register for the live zoom link here: https://cornell.zoom.us/webinar/register/WN_q-MdWv0FQD2Y7Ww6FIINDg
Microbe named after Gene
Scanning Electron Microscrope (SEM) image of P. madseniana.
Select writings about the species named after Gene
- Wilhelm et al. Phenolic acid-degrading Paraburkholderia prime decomposition in forest soil. ISME Communications (2021) 1:4 ; https://doi.org/10.1038/s43705-021-00009-z
Plant-derived phenolic acids are catabolized by soil microorganisms whose activity may enhance the decomposition of soil organic carbon (SOC). We characterized whether phenolic acid-degrading bacteria enhance SOC mineralization in forest soils when primed with 13C-labeled p-hydroxybenzoic acid (pHB). We further tested whether pHB-induced priming could explain differences in SOC content among mono-specific tree plantations in a 70-year-old common garden experiment. pHB addition primed significant losses of SOC (3–13 μmols C g−1 dry wt soil over 7 days) compared to glucose, which reduced mineralization (-3 to -8 μmols C g−1 dry wt soil over 7 days). The principal degraders of pHB were Paraburkholderia and Caballeronia in all plantations regardless of tree species or soil type, with one predominant phylotype (RP11ASV) enriched 23-fold following peak pHB respiration. We isolated and confirmed the phenolic degrading activity of a strain matching this phylotype (RP11T), which encoded numerous oxidative enzymes, including secretion signal-bearing laccase, Dyp-type peroxidase and aryl-alcohol oxidase. Increased relative abundance of RP11ASV corresponded with higher pHB respiration and expression of pHB monooxygenase (pobA), which was inversely proportional to SOC content among plantations. pobA expression proved a responsive measure of priming activity. We found that stimulating phenolic acid degrading bacteria can prime decomposition and that this activity, corresponding with differences in tree species, is a potential mechanism in SOC cycling in forests. Overall, this study highlights the ecology and function of Paraburkholderia whose associations with plant roots and capacity to degrade phenolics suggest a role for specialized bacteria in the priming effect.
- Wilhelm et al. Paraburkholderia madseniana sp. nov., a phenolic acid-degrading bacterium isolated from acidic forest soil. Int. J. Syst. Evol. Microbiol. DOI.10.1099/ijsem.0.004029
ABSTRACT: RP11T was isolated from forest soil following enrichment with 4-hydroxybenzoicacid. Cells of RP11T are aerobic, non-sporulating, exhibit swimming motility, and are rods (0.8 μm by 1.4 μm) that often occur as diplobacillus or in short chains (3–4 cells). Optimal growth on minimal media containing 4-hydroxybenzoic acid (μ=0.216 hr−1) occurred at 30 °C, pH 6.5 or 7.0 and 0% salinity. Comparative chemotaxonomic, genomic and phylogenetic analyses revealed the isolate was distinct from its closest relative type strains identified as Paraburkholderia aspalathi LMG 27731T, Paraburkholderia fungorum LMG 16225T and Paraburkholderia caffeinilytica CF1T. Strain RP11T is genetically distinct from P. aspalathi, its closest relative, in terms of 16S rRNA gene sequence similarity (98.7%), genomic average nucleotide identity (94%) and in silico DNA–DNA hybridization (56.7 %±2.8). The composition of fatty acids and substrate utilization pattern differentiated strain RP11T from its closest relatives, including growth on phthalic acid. Strain RP11T encoded the greatest number of aromatic degradation genes of all eleven closely related type strains and uniquely encoded a phthalic acid dioxygenase and paralog of the 3-hydroxybenzoate 4-monooxygenase. The only ubiquinone detected in strain RP11T was Q-8, and the major cellular fatty acids were C16 : 0, 3OH-C16 : 0, C17 : 0 cyclo, C19 : 0 cyclo ω8c, and summed
feature 8 (C18 : 1 ω7c/ω6c). On the basis of this polyphasic approach, it was determined that strain RP11T represents a novel species from the genus Paraburkholderia for which the name Paraburkholderia madseniana sp. nov. is proposed. The type strain is RP11T (=DSM 110123T=LMG 31517T).
On a personal note, Gene was a person I didn't know all that well. But as a young scientist, I watched him. I knew he was one of the few people on campus who understood climate change early and on a visceral level; he rode his bike to work with both purpose and freedom of choice. When I installed Vector - an installation of data visualizations (his graph was one of the selected) for the Mann Library courtyard. When I converted these graphic images to domestic items for the first gallery show in Mann Library (Visualizing Meaning, 2006) - he agreed to be interviewed for a documentary film that Cornell Libraries commissioned; he noted the importance of integrating data into the aesthetics of daily lives (see minute 4:50 of http://audiblewink.com/CopyingMasters.html).
At some point, I became honored with his solstice/new year cards - simple line drawing comics of glaciers with existential thought bubbles. Sometime before he died, he reached out asking me how he could perhaps have a show of them; I was not successful in helping him though he has published a book of them. To me, Gene was an integrator of life. He, like Sergei Winogradsky was curious about the cycle.