Tim Devarenne

Associate Head for Undergraduate Programs
Associate Professor | Biochemistry & Biophysics

algal hydrocarbons, Botryococcus braunii, plant pathogen interactions, programmed cell death, protein kinase signaling

Office:NMR / N218A
Email:tpd8@tamu.edu
Phone:979-862-6509

The Devarenne lab focuses on identifying the genes and enzymes involved in hydrocarbon biosynthesis in the green microalga Botryococcus braunii and analyzing how plants control programmed cell death to control resistance to bacterial pathogens.

Algal hydrocarbon biosynthesis

 A confocal microscopy image of a B. braunii colony showing chloroplast localization from chlorophyll autofluorescence (red) and stained with Nile red (green) to visualize the liquid hydrocarbons.
See ACS Chem. Biol. 12, 2408–2416 (2017).

Botryococcus braunii is a colony-forming green microalga that is well known for producing large quantities of liquid hydrocarbons, which can be converted into petroleum-equivalent combustion engine fuels. Thus, B. braunii hydrocarbons are a potential renewable source of transportation fuels. Interestingly, B. braunii hydrocarbons have been shown to be a major constituent of currently used petroleum deposits. We are studying the genes involved in the biosynthesis of the B. braunii liquid hydrocarbons from three different chemical races of the alga. Each race produces a different molecular type of hydrocarbon. Our studies include using transcriptomic and genomic data to identify hydrocarbon biosynthesis genes, cloning these genes, and functionally characterizing the enzymes encoded by these genes.

M. Tatli, M. T. Naik, S. Okada, L. J. Dangott, T. P. Devarenne, Isolation and characterization of cyclic C33 botryococcenes and a trimethylsqualene isomer from Botryococcus braunii race B. J. Nat. Prod. 80, 953–958 (2017).

H. R. Thapa, M. T. Naik, S. Okada, K. Takada, I. Molnar, Y. Xu, T. P. Devarenne, A squalene synthase-like enzyme initiates production of tetraterpenoid hydrocarbons in Botryococcus braunii race L. Nat. Commun. 7 (2016).

Control of plant programmed cell death

Pathway for the control of PCD by the S/T AGC protein kinase Adi3 under normal conditions and in response to P. syringae.
See PLoS One 9 (2014).

We study the biochemical and molecular mechanisms underlying the control of programmed cell death (PCD) in plants and how PCD is manipulated during plant-pathogen interactions. Specifically, we study the interaction between tomato and Pseudomonas syringae pv. tomato (Pst) the causative agent of bacterial speck disease. During the tomato resistance response to Pst, PCD is induced by the plant to limit the spread of the pathogen. Many of the genes that control plant PCD are serine/threonine (S/T) protein kinase. We are interested in studying a specific class of S/T protein kinases that control PCD in plants called AGC kinases and how they are regulated during the plant resistance response. Moreover, looking at the signaling mechanisms and pathways employed by AGC kinases to control PCD when tomato plants are attacked by Pst as well as understanding how PCD is kept in check in non-pathogen challenged plants.

I.-C. Yeo and T. P. Devarenne, Screening for potential nuclear substrates for the plant cell death suppressor kinase Adi3 using peptide microarrays. PLoS One 15 (2020).

T. P. Devarenne, S. K. Ekengren, K. F. Pedley, G. B. Martin, Adi3 is a Pdk1-interacting AGC kinase that negatively regulates plant cell death. EMBO Journal 25, 255–265 (2006).