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Smith RA, Cass CL, Petrik DL, Padmakshan D, Ralph J, Sedbrook JC, Karlen SD. Stacking AsFMT overexpression with BdPMT loss of function enhances monolignol ferulate production in Brachypodium distachyon. Plant Biotechnol J 2021; 19:1878-1886. [PMID: 33949064 PMCID: PMC8428837 DOI: 10.1111/pbi.13606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 04/09/2021] [Accepted: 04/13/2021] [Indexed: 06/12/2023]
Abstract
To what degree can the lignin subunits in a monocot be derived from monolignol ferulate (ML-FA) conjugates? This simple question comes with a complex set of variables. Three potential requirements for optimizing ML-FA production are as follows: (1) The presence of an active FERULOYL-CoA MONOLIGNOL TRANSFERASE (FMT) enzyme throughout monolignol production; (2) Suppression or elimination of enzymatic pathways competing for monolignols and intermediates during lignin biosynthesis; and (3) Exclusion of alternative phenolic compounds that participate in lignification. A 16-fold increase in lignin-bound ML-FA incorporation was observed by introducing an AsFMT gene into Brachypodium distachyon. On its own, knocking out the native p-COUMAROYL-CoA MONOLIGNOL TRANSFERASE (BdPMT) pathway that competes for monolignols and the p-coumaroyl-CoA intermediate did not change ML-FA incorporation, nor did partial loss of CINNAMOYL-CoA REDUCTASE1 (CCR1) function, which reduced metabolic flux to monolignols. However, stacking AsFMT into the Bdpmt-1 mutant resulted in a 32-fold increase in ML-FA incorporation into lignin over the wild-type level.
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Affiliation(s)
- Rebecca A. Smith
- U.S. Department of Energy Great Lakes Bioenergy Research Center and the Department of BiochemistryWisconsin Energy InstituteUniversity of WisconsinMadisonWIUSA
| | - Cynthia L. Cass
- School of Biological SciencesIllinois State UniversityNormalILUSA
- U.S. Department of Energy Great Lakes Bioenergy Research CenterMadisonWIUSA
| | - Deborah L. Petrik
- School of Biological SciencesIllinois State UniversityNormalILUSA
- U.S. Department of Energy Great Lakes Bioenergy Research CenterMadisonWIUSA
- Department of BiologyNortheastern State UniversityTahlequahOKUSA
| | - Dharshana Padmakshan
- U.S. Department of Energy Great Lakes Bioenergy Research Center and the Department of BiochemistryWisconsin Energy InstituteUniversity of WisconsinMadisonWIUSA
| | - John Ralph
- U.S. Department of Energy Great Lakes Bioenergy Research Center and the Department of BiochemistryWisconsin Energy InstituteUniversity of WisconsinMadisonWIUSA
| | - John C. Sedbrook
- School of Biological SciencesIllinois State UniversityNormalILUSA
- U.S. Department of Energy Great Lakes Bioenergy Research CenterMadisonWIUSA
| | - Steven D. Karlen
- U.S. Department of Energy Great Lakes Bioenergy Research Center and the Department of BiochemistryWisconsin Energy InstituteUniversity of WisconsinMadisonWIUSA
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Karlen SD, Fasahati P, Mazaheri M, Serate J, Smith RA, Sirobhushanam S, Chen M, Tymokhin VI, Cass CL, Liu S, Padmakshan D, Xie D, Zhang Y, McGee MA, Russell JD, Coon JJ, Kaeppler HF, de Leon N, Maravelias CT, Runge TM, Kaeppler SM, Sedbrook JC, Ralph J. Assessing the Viability of Recovery of Hydroxycinnamic Acids from Lignocellulosic Biorefinery Alkaline Pretreatment Waste Streams. ChemSusChem 2020; 13:1922. [PMID: 32285625 DOI: 10.1002/cssc.202000820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Invited for this month's cover is the research team from the D.O.E. Great Lake Bioenergy Research Center (GLBRC) at the University of Wisconsin-Madison. The cover image shows how a diverse team with expertise in many different fields works together in an integrated fashion to address complex problems. Only when the whole system, from field to the liquid fuels and co-products, is assessed, can we identify the key parameters needed to design an economically viable biorefinery-based economy. Cover art by Chelsea Mamott. The Full Paper itself is available at 10.1002/cssc.201903345.
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Affiliation(s)
- Steven D Karlen
- DOE Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, WI, 53726, USA
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Peyman Fasahati
- DOE Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, WI, 53726, USA
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Mona Mazaheri
- DOE Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, WI, 53726, USA
- Department of Agronomy, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Jose Serate
- DOE Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, WI, 53726, USA
| | - Rebecca A Smith
- DOE Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, WI, 53726, USA
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Sirisha Sirobhushanam
- DOE Great Lakes Bioenergy Research Center, School of Biological Sciences, Illinois State University, Normal, IL, 61790, USA
| | - Mingjie Chen
- DOE Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, WI, 53726, USA
- Department of Biological Systems Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Vitaliy I Tymokhin
- DOE Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, WI, 53726, USA
| | - Cynthia L Cass
- DOE Great Lakes Bioenergy Research Center, School of Biological Sciences, Illinois State University, Normal, IL, 61790, USA
| | - Sarah Liu
- DOE Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, WI, 53726, USA
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Dharshana Padmakshan
- DOE Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, WI, 53726, USA
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Dan Xie
- DOE Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, WI, 53726, USA
| | - Yaoping Zhang
- DOE Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, WI, 53726, USA
| | - Mick A McGee
- DOE Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, WI, 53726, USA
| | - Jason D Russell
- DOE Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, WI, 53726, USA
- Morgridge Institute for Research, Madison, WI, 53715, USA
| | - Joshua J Coon
- DOE Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, WI, 53726, USA
- Morgridge Institute for Research, Madison, WI, 53715, USA
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Heidi F Kaeppler
- DOE Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, WI, 53726, USA
- Department of Agronomy, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Natalia de Leon
- DOE Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, WI, 53726, USA
- Department of Agronomy, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Christos T Maravelias
- DOE Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, WI, 53726, USA
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Troy M Runge
- Department of Biological Systems Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Shawn M Kaeppler
- DOE Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, WI, 53726, USA
- Department of Agronomy, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - John C Sedbrook
- DOE Great Lakes Bioenergy Research Center, School of Biological Sciences, Illinois State University, Normal, IL, 61790, USA
| | - John Ralph
- DOE Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, WI, 53726, USA
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
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Karlen SD, Fasahati P, Mazaheri M, Serate J, Smith RA, Sirobhushanam S, Chen M, Tymokhin VI, Cass CL, Liu S, Padmakshan D, Xie D, Zhang Y, McGee MA, Russell JD, Coon JJ, Kaeppler HF, de Leon N, Maravelias CT, Runge TM, Kaeppler SM, Sedbrook JC, Ralph J. Assessing the Viability of Recovery of Hydroxycinnamic Acids from Lignocellulosic Biorefinery Alkaline Pretreatment Waste Streams. ChemSusChem 2020; 13:2012-2024. [PMID: 31984673 PMCID: PMC7217007 DOI: 10.1002/cssc.201903345] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Indexed: 05/03/2023]
Abstract
The hydroxycinnamic acids p-coumaric acid (pCA) and ferulic acid (FA) add diversity to the portfolio of products produced by using grass-fed lignocellulosic biorefineries. The level of lignin-bound pCA in Zea mays was modified by the alteration of p-coumaroyl-CoA monolignol transferase expression. The biomass was processed in a lab-scale alkaline-pretreatment biorefinery process and the data were used for a baseline technoeconomic analysis to determine where to direct future research efforts to couple plant design to biomass utilization processes. It is concluded that future plant engineering efforts should focus on strategies that ramp up accumulation of one type of hydroxycinnamate (pCA or FA) predominantly and suppress that of the other. Technoeconomic analysis indicates that target extraction titers of one hydroxycinnamic acid need to be >50 g kg-1 biomass, at least five times higher than observed titers for the impure pCA/FA product mixture from wild-type maize. The technical challenge for process engineers is to develop a viable process that requires more than 80 % reduction of the isolation costs.
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Vallejo R, Platt DC, Rink JA, Jones MA, Kelley CA, Gupta A, Cass CL, Eichenberg K, Vallejo A, Smith WJ, Benyamin R, Cedeño DL. Electrical Stimulation of C6 Glia-Precursor Cells In Vitro Differentially Modulates Gene Expression Related to Chronic Pain Pathways. Brain Sci 2019; 9:brainsci9110303. [PMID: 31683631 PMCID: PMC6896182 DOI: 10.3390/brainsci9110303] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 10/27/2019] [Accepted: 10/29/2019] [Indexed: 12/21/2022] Open
Abstract
Glial cells comprise the majority of cells in the central nervous system and exhibit diverse functions including the development of persistent neuropathic pain. While earlier theories have proposed that the applied electric field specifically affects neurons, it has been demonstrated that electrical stimulation (ES) of neural tissue modulates gene expression of the glial cells. This study examines the effect of ES on the expression of eight genes related to oxidative stress and neuroprotection in cultured rodent glioma cells. Concentric bipolar electrodes under seven different ES types were used to stimulate cells for 30 min in the presence and absence of extracellular glutamate. ES consisted of rectangular pulses at 50 Hz in varying proportions of anodic and cathodic phases. Real-time reverse-transcribed quantitative polymerase chain reaction was used to determine gene expression using the ∆∆Cq method. The results demonstrate that glutamate has a significant effect on gene expression in both stimulated and non-stimulated groups. Furthermore, stimulation parameters have differential effects on gene expression, both in the presence and absence of glutamate. ES has an effect on glial cell gene expression that is dependent on waveform composition. Optimization of ES therapy for chronic pain applications can be enhanced by this understanding.
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Affiliation(s)
- Ricardo Vallejo
- Millennium Pain Center, Bloomington, IL 61704, USA.
- Department of Psychology, Illinois Wesleyan University, Bloomington, IL 61701, USA.
| | - David C Platt
- Department of Chemistry, Illinois State University, Normal, IL 61790, USA.
| | - Jonathan A Rink
- Department of Biology, Illinois Wesleyan University, Bloomington, IL 61701, USA.
| | - Marjorie A Jones
- Department of Chemistry, Illinois State University, Normal, IL 61790, USA.
| | - Courtney A Kelley
- Millennium Pain Center, Bloomington, IL 61704, USA.
- Department of Psychology, Illinois Wesleyan University, Bloomington, IL 61701, USA.
| | - Ashim Gupta
- Millennium Pain Center, Bloomington, IL 61704, USA.
- Department of Psychology, Illinois Wesleyan University, Bloomington, IL 61701, USA.
- South Texas Orthopaedic Research Institute, Laredo, TX 78045, USA.
| | - Cynthia L Cass
- Millennium Pain Center, Bloomington, IL 61704, USA.
- Department of Psychology, Illinois Wesleyan University, Bloomington, IL 61701, USA.
| | - Kirk Eichenberg
- Department of Chemistry, Illinois State University, Normal, IL 61790, USA.
| | | | - William J Smith
- Millennium Pain Center, Bloomington, IL 61704, USA.
- Geisel School of Medicine, Dartmouth College, Hanover, NH 03755, USA.
| | - Ramsin Benyamin
- Millennium Pain Center, Bloomington, IL 61704, USA.
- Department of Psychology, Illinois Wesleyan University, Bloomington, IL 61701, USA.
- College of Medicine, Department of Surgery, University of Illinois at Urbana-Champaign, Champaign-Urbana, IL 61801, USA.
| | - David L Cedeño
- Millennium Pain Center, Bloomington, IL 61704, USA.
- Department of Psychology, Illinois Wesleyan University, Bloomington, IL 61701, USA.
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Vallejo R, Gupta A, Kelley CA, Vallejo A, Rink J, Williams JM, Cass CL, Smith WJ, Benyamin R, Cedeño DL. Effects of Phase Polarity and Charge Balance Spinal Cord Stimulation on Behavior and Gene Expression in a Rat Model of Neuropathic Pain. Neuromodulation 2019; 23:26-35. [PMID: 31070863 DOI: 10.1111/ner.12964] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 03/12/2019] [Accepted: 04/03/2019] [Indexed: 12/20/2022]
Affiliation(s)
- Ricardo Vallejo
- Millennium Pain Center Bloomington IL USA
- Department of PsychologyIllinois Wesleyan University Bloomington IL USA
| | - Ashim Gupta
- Millennium Pain Center Bloomington IL USA
- Department of PsychologyIllinois Wesleyan University Bloomington IL USA
- South Texas Orthopaedic Research Institute Laredo TX USA
| | - Courtney A. Kelley
- Millennium Pain Center Bloomington IL USA
- Department of PsychologyIllinois Wesleyan University Bloomington IL USA
| | | | - Jonathan Rink
- Department of BiologyIllinois Wesleyan University Bloomington IL USA
| | | | - Cynthia L. Cass
- Millennium Pain Center Bloomington IL USA
- Department of PsychologyIllinois Wesleyan University Bloomington IL USA
| | - William J. Smith
- Millennium Pain Center Bloomington IL USA
- Geisel School of MedicineDartmouth College Hanover NH USA
| | - Ramsin Benyamin
- Millennium Pain Center Bloomington IL USA
- Department of PsychologyIllinois Wesleyan University Bloomington IL USA
- College of MedicineUniversity of Illinois at Urbana‐Champaign Champaign‐Urbana IL USA
| | - David L. Cedeño
- Millennium Pain Center Bloomington IL USA
- Department of PsychologyIllinois Wesleyan University Bloomington IL USA
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Dorsey BM, Cass CL, Cedeño DL, Vallejo R, Jones MA. Effects of Specific Electric Field Stimulation on the Release and Activity of Secreted Acid Phosphatases from Leishmania tarentolae and Implications for Therapy. Pathogens 2018; 7:pathogens7040077. [PMID: 30261701 PMCID: PMC6313409 DOI: 10.3390/pathogens7040077] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 08/31/2018] [Accepted: 09/21/2018] [Indexed: 11/29/2022] Open
Abstract
Leishmaniasis is a neglected tropical disease with 1.6 million new cases reported each year. However, there are few safe, effective, and affordable treatments provided to those affected by this disease. Still under-appreciated as potential pharmaceutical targets, especially for cutaneous leishmaniasis infections, are the two isozymes of secreted acid phosphatase (SAP). These enzymes are involved in the survival of the parasite in the sand fly vector, and in infecting host macrophages. While the application of electric or electromagnetic fields as a medicinal therapeutic is not new, the utility of electric field application for the treatment of leishmaniasis is under studied. Studies involving the effects of electric fields on the cell secretion of SAP or the activity of SAP that has been secreted prior to electrical stimulation have not yet been reported. This work is the first report on the effect of specific electric fields on the activity of Leishmaniatarentolae secreted acid phosphatases and the modulation of this secretion from the cells. In addition, the kinetic constants for the enzyme isoforms were determined as a function of days in culture and removal of carbohydrate from the glycosylated enzymes, while using a glycosidase, was shown to affect these kinetic constants.
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Affiliation(s)
- Benjamin M Dorsey
- Department of Chemistry, Illinois State University, Normal, IL 61790-4160, USA.
| | - Cynthia L Cass
- Millennium Pain Center, Bloomington, IL 61704-0303, USA.
| | - David L Cedeño
- Millennium Pain Center, Bloomington, IL 61704-0303, USA.
| | | | - Marjorie A Jones
- Department of Chemistry, Illinois State University, Normal, IL 61790-4160, USA.
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Smith RA, Cass CL, Mazaheri M, Sekhon RS, Heckwolf M, Kaeppler H, de Leon N, Mansfield SD, Kaeppler SM, Sedbrook JC, Karlen SD, Ralph J. Suppression of CINNAMOYL- CoA REDUCTASE increases the level of monolignol ferulates incorporated into maize lignins. Biotechnol Biofuels 2017; 10:109. [PMID: 28469705 PMCID: PMC5414125 DOI: 10.1186/s13068-017-0793-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Accepted: 04/18/2017] [Indexed: 05/02/2023]
Abstract
BACKGROUND The cell wall polymer lignin provides structural support and rigidity to plant cell walls, and therefore to the plant body. However, the recalcitrance associated with lignin impedes the extraction of polysaccharides from the cell wall to make plant-based biofuels and biomaterials. The cell wall digestibility can be improved by introducing labile ester bonds into the lignin backbone that can be easily broken under mild base treatment at room temperature. The FERULOYL-CoA MONOLIGNOL TRANSFERASE (FMT) enzyme, which may be naturally found in many plants, uses feruloyl-CoA and monolignols to synthesize the ester-linked monolignol ferulate conjugates. A mutation in the first lignin-specific biosynthetic enzyme, CINNAMOYL-CoA REDUCTASE (CCR), results in an increase in the intracellular pool of feruloyl-CoA. RESULTS Maize (Zea mays) has a native putative FMT enzyme, and its ccr mutants produce an increased pool of feruloyl-CoA that can be used for conversion to monolignol ferulate conjugates. The decreased lignin content and monomers did not, however, impact the plant growth or biomass. The increase in monolignol conjugates correlated with an improvement in the digestibility of maize stem rind tissue. CONCLUSIONS Together, increased monolignol ferulates and improved digestibility in ccr1 mutant plants suggests that they may be superior biofuel crops.
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Affiliation(s)
- Rebecca A. Smith
- Department of Energy Great Lakes Bioenergy Research Center, The Wisconsin Energy Institute, University of Wisconsin-Madison, 1552 University Avenue, Madison, WI 53726-4084 USA
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706 USA
| | - Cynthia L. Cass
- Department of Energy Great Lakes Bioenergy Research Center, School of Biological Sciences, Illinois State University, Normal, IL 61790 USA
| | - Mona Mazaheri
- Department of Energy Great Lakes Bioenergy Research Center, The Wisconsin Energy Institute, University of Wisconsin-Madison, 1552 University Avenue, Madison, WI 53726-4084 USA
- Department of Agronomy, University of Wisconsin-Madison, Madison, WI 53706 USA
| | - Rajandeep S. Sekhon
- Department of Energy Great Lakes Bioenergy Research Center, The Wisconsin Energy Institute, University of Wisconsin-Madison, 1552 University Avenue, Madison, WI 53726-4084 USA
- Department of Agronomy, University of Wisconsin-Madison, Madison, WI 53706 USA
- Department of Genetics and Biochemistry, Clemson University, Clemson, USA
| | - Marlies Heckwolf
- Department of Energy Great Lakes Bioenergy Research Center, The Wisconsin Energy Institute, University of Wisconsin-Madison, 1552 University Avenue, Madison, WI 53726-4084 USA
- Department of Agronomy, University of Wisconsin-Madison, Madison, WI 53706 USA
| | - Heidi Kaeppler
- Department of Energy Great Lakes Bioenergy Research Center, The Wisconsin Energy Institute, University of Wisconsin-Madison, 1552 University Avenue, Madison, WI 53726-4084 USA
- Department of Agronomy, University of Wisconsin-Madison, Madison, WI 53706 USA
| | - Natalia de Leon
- Department of Energy Great Lakes Bioenergy Research Center, The Wisconsin Energy Institute, University of Wisconsin-Madison, 1552 University Avenue, Madison, WI 53726-4084 USA
- Department of Agronomy, University of Wisconsin-Madison, Madison, WI 53706 USA
| | - Shawn D. Mansfield
- Department of Wood Science, University of British Columbia, Vancouver, BC Canada
| | - Shawn M. Kaeppler
- Department of Energy Great Lakes Bioenergy Research Center, The Wisconsin Energy Institute, University of Wisconsin-Madison, 1552 University Avenue, Madison, WI 53726-4084 USA
- Department of Agronomy, University of Wisconsin-Madison, Madison, WI 53706 USA
| | - John C. Sedbrook
- Department of Energy Great Lakes Bioenergy Research Center, School of Biological Sciences, Illinois State University, Normal, IL 61790 USA
| | - Steven D. Karlen
- Department of Energy Great Lakes Bioenergy Research Center, The Wisconsin Energy Institute, University of Wisconsin-Madison, 1552 University Avenue, Madison, WI 53726-4084 USA
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706 USA
| | - John Ralph
- Department of Energy Great Lakes Bioenergy Research Center, The Wisconsin Energy Institute, University of Wisconsin-Madison, 1552 University Avenue, Madison, WI 53726-4084 USA
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706 USA
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Petrik DL, Cass CL, Padmakshan D, Foster CE, Vogel JP, Karlen SD, Ralph J, Sedbrook JC. BdCESA7, BdCESA8, and BdPMT Utility Promoter Constructs for Targeted Expression to Secondary Cell-Wall-Forming Cells of Grasses. Front Plant Sci 2016; 7:55. [PMID: 26870070 PMCID: PMC4740387 DOI: 10.3389/fpls.2016.00055] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2015] [Accepted: 01/14/2016] [Indexed: 05/13/2023]
Abstract
Utility vectors with promoters that confer desired spatial and temporal expression patterns are useful tools for studying gene and cellular function and for industrial applications. To target the expression of DNA sequences of interest to cells forming plant secondary cell walls, which generate most of the vegetative biomass, upstream regulatory sequences of the Brachypodium distachyon lignin biosynthetic gene BdPMT and the cellulose synthase genes BdCESA7 and BdCESA8 were isolated and cloned into binary vectors designed for Agrobacterium-mediated transformation of monocots. Expression patterns were assessed using the β-glucuronidase gene GUSPlus and X-glucuronide staining. All three promoters showed strong expression levels in stem tissue at the base of internodes where cell wall deposition is most active, in both vascular bundle xylem vessels and tracheids, and in interfascicular tissues, with expression less pronounced in developmentally older tissues. In leaves, BdCESA7 and BdCESA8 promoter-driven expression was strongest in leaf veins, leaf margins, and trichomes; relatively weaker and patchy expression was observed in the epidermis. BdPMT promoter-driven expression was similar to the BdCESA promoters expression patterns, including strong expression in trichomes. The intensity and extent of GUS staining varied considerably between transgenic lines, suggesting that positional effects influenced promoter activity. Introducing the BdPMT and BdCESA8 Open Reading Frames into BdPMT and BdCESA8 utility promoter binary vectors, respectively, and transforming those constructs into Brachypodium pmt and cesa8 loss-of-function mutants resulted in rescue of the corresponding mutant phenotypes. This work therefore validates the functionality of these utility promoter binary vectors for use in Brachypodium and likely other grass species. The identification, in Bdcesa8-1 T-DNA mutant stems, of an 80% reduction in crystalline cellulose levels confirms that the BdCESA8 gene is a secondary-cell-wall-forming cellulose synthase.
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Affiliation(s)
- Deborah L. Petrik
- School of Biological Sciences, Illinois State University, NormalIL, USA
- U.S. Department of Energy Great Lakes Bioenergy Research Center, University of Wisconsin–Madison, MadisonWI, USA
| | - Cynthia L. Cass
- School of Biological Sciences, Illinois State University, NormalIL, USA
- U.S. Department of Energy Great Lakes Bioenergy Research Center, University of Wisconsin–Madison, MadisonWI, USA
| | - Dharshana Padmakshan
- U.S. Department of Energy Great Lakes Bioenergy Research Center, University of Wisconsin–Madison, MadisonWI, USA
| | - Cliff E. Foster
- U.S. Department of Energy Great Lakes Bioenergy Research Center, Michigan State University, East LansingMI, USA
| | - John P. Vogel
- U.S. Department of Energy Joint Genome Institute, Walnut CreekCA, USA
| | - Steven D. Karlen
- U.S. Department of Energy Great Lakes Bioenergy Research Center, University of Wisconsin–Madison, MadisonWI, USA
| | - John Ralph
- U.S. Department of Energy Great Lakes Bioenergy Research Center, University of Wisconsin–Madison, MadisonWI, USA
- Department of Biochemistry, Wisconsin Energy Institute, University of Wisconsin–Madison, MadisonWI, USA
| | - John C. Sedbrook
- School of Biological Sciences, Illinois State University, NormalIL, USA
- U.S. Department of Energy Great Lakes Bioenergy Research Center, University of Wisconsin–Madison, MadisonWI, USA
- *Correspondence: John C. Sedbrook,
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Cass CL, Lavell AA, Santoro N, Foster CE, Karlen SD, Smith RA, Ralph J, Garvin DF, Sedbrook JC. Cell Wall Composition and Biomass Recalcitrance Differences Within a Genotypically Diverse Set of Brachypodium distachyon Inbred Lines. Front Plant Sci 2016; 7:708. [PMID: 27303415 PMCID: PMC4880586 DOI: 10.3389/fpls.2016.00708] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Accepted: 05/09/2016] [Indexed: 05/09/2023]
Abstract
Brachypodium distachyon (Brachypodium) has emerged as a useful model system for studying traits unique to graminaceous species including bioenergy crop grasses owing to its amenability to laboratory experimentation and the availability of extensive genetic and germplasm resources. Considerable natural variation has been uncovered for a variety of traits including flowering time, vernalization responsiveness, and above-ground growth characteristics. However, cell wall composition differences remain underexplored. Therefore, we assessed cell wall-related traits relevant to biomass conversion to biofuels in seven Brachypodium inbred lines that were chosen based on their high level of genotypic diversity as well as available genome sequences and recombinant inbred line (RIL) populations. Senesced stems plus leaf sheaths from these lines exhibited significant differences in acetyl bromide soluble lignin (ABSL), cell wall polysaccharide-derived sugars, hydroxycinnamates content, and syringyl:guaiacyl:p-hydroxyphenyl (S:G:H) lignin ratios. Free glucose, sucrose, and starch content also differed significantly in senesced stems, as did the amounts of sugars released from cell wall polysaccharides (digestibility) upon exposure to a panel of thermochemical pretreatments followed by hydrolytic enzymatic digestion. Correlations were identified between inbred line lignin compositions and plant growth characteristics such as biomass accumulation and heading date (HD), and between amounts of cell wall polysaccharides and biomass digestibility. Finally, stem cell wall p-coumarate and ferulate contents and free-sugars content changed significantly with increased duration of vernalization for some inbred lines. Taken together, these results show that Brachypodium displays substantial phenotypic variation with respect to cell wall composition and biomass digestibility, with some compositional differences correlating with growth characteristics. Moreover, besides influencing HD and biomass accumulation, vernalization was found to affect cell wall composition and free sugars accumulation in some Brachypodium inbred lines, suggesting genetic differences in how vernalization affects carbon flux to polysaccharides. The availability of related RIL populations will allow for the genetic and molecular dissection of this natural variation, the knowledge of which may inform ways to genetically improve bioenergy crop grasses.
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Affiliation(s)
- Cynthia L. Cass
- School of Biological Sciences, Illinois State University, NormalIL, USA
- U.S. Department of Energy Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, MadisonWI, USA
| | - Anastasiya A. Lavell
- Department of Agronomy and Plant Genetics, University of Minnesota, St. PaulMN, USA
- Plant Science Research Unit, United States Department of Agriculture, Agricultural Research Service, St. PaulMN, USA
| | - Nicholas Santoro
- U.S. Department of Energy Great Lakes Bioenergy Research Center, Michigan State University, East LansingMI, USA
| | - Cliff E. Foster
- U.S. Department of Energy Great Lakes Bioenergy Research Center, Michigan State University, East LansingMI, USA
| | - Steven D. Karlen
- U.S. Department of Energy Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, MadisonWI, USA
| | - Rebecca A. Smith
- U.S. Department of Energy Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, MadisonWI, USA
| | - John Ralph
- U.S. Department of Energy Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, MadisonWI, USA
- Department of Biochemistry, University of Wisconsin-Madison, MadisonWI, USA
| | - David F. Garvin
- Department of Agronomy and Plant Genetics, University of Minnesota, St. PaulMN, USA
- Plant Science Research Unit, United States Department of Agriculture, Agricultural Research Service, St. PaulMN, USA
| | - John C. Sedbrook
- School of Biological Sciences, Illinois State University, NormalIL, USA
- U.S. Department of Energy Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, MadisonWI, USA
- *Correspondence: John C. Sedbrook,
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Cass CL, Peraldi A, Dowd PF, Mottiar Y, Santoro N, Karlen SD, Bukhman YV, Foster CE, Thrower N, Bruno LC, Moskvin OV, Johnson ET, Willhoit ME, Phutane M, Ralph J, Mansfield SD, Nicholson P, Sedbrook JC. Effects of PHENYLALANINE AMMONIA LYASE (PAL) knockdown on cell wall composition, biomass digestibility, and biotic and abiotic stress responses in Brachypodium. J Exp Bot 2015; 66:4317-35. [PMID: 26093023 PMCID: PMC4493789 DOI: 10.1093/jxb/erv269] [Citation(s) in RCA: 109] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
The phenylpropanoid pathway in plants synthesizes a variety of structural and defence compounds, and is an important target in efforts to reduce cell wall lignin for improved biomass conversion to biofuels. Little is known concerning the trade-offs in grasses when perturbing the function of the first gene family in the pathway, PHENYLALANINE AMMONIA LYASE (PAL). Therefore, PAL isoforms in the model grass Brachypodium distachyon were targeted, by RNA interference (RNAi), and large reductions (up to 85%) in stem tissue transcript abundance for two of the eight putative BdPAL genes were identified. The cell walls of stems of BdPAL-knockdown plants had reductions of 43% in lignin and 57% in cell wall-bound ferulate, and a nearly 2-fold increase in the amounts of polysaccharide-derived carbohydrates released by thermochemical and hydrolytic enzymic partial digestion. PAL-knockdown plants exhibited delayed development and reduced root growth, along with increased susceptibilities to the fungal pathogens Fusarium culmorum and Magnaporthe oryzae. Surprisingly, these plants generally had wild-type (WT) resistances to caterpillar herbivory, drought, and ultraviolet light. RNA sequencing analyses revealed that the expression of genes associated with stress responses including ethylene biosynthesis and signalling were significantly altered in PAL knocked-down plants under non-challenging conditions. These data reveal that, although an attenuation of the phenylpropanoid pathway increases carbohydrate availability for biofuel, it can adversely affect plant growth and disease resistance to fungal pathogens. The data identify notable differences between the stress responses of these monocot pal mutants versus Arabidopsis (a dicot) pal mutants and provide insights into the challenges that may arise when deploying phenylpropanoid pathway-altered bioenergy crops.
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Affiliation(s)
- Cynthia L Cass
- School of Biological Sciences, Illinois State University, Normal, IL 61790 USA US Department of Energy Great Lakes Bioenergy Research Center, Madison, WI 53706, USA
| | - Antoine Peraldi
- Department of Crop Genetics, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
| | - Patrick F Dowd
- USDA, Agricultural Research Service, National Center for Agricultural Utilization Research, Crop Bioprotection Research Unit, Peoria, IL 61604, USA
| | - Yaseen Mottiar
- US Department of Energy Great Lakes Bioenergy Research Center, Madison, WI 53706, USA Department of Wood Science, University of British Columbia, Vancouver, V6T 1Z4, Canada
| | - Nicholas Santoro
- US Department of Energy Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI 48824, USA
| | - Steven D Karlen
- US Department of Energy Great Lakes Bioenergy Research Center, Madison, WI 53706, USA
| | - Yury V Bukhman
- US Department of Energy Great Lakes Bioenergy Research Center, Madison, WI 53706, USA
| | - Cliff E Foster
- US Department of Energy Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI 48824, USA
| | - Nick Thrower
- US Department of Energy Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI 48824, USA
| | - Laura C Bruno
- Department of Crop Genetics, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
| | - Oleg V Moskvin
- US Department of Energy Great Lakes Bioenergy Research Center, Madison, WI 53706, USA
| | - Eric T Johnson
- USDA, Agricultural Research Service, National Center for Agricultural Utilization Research, Crop Bioprotection Research Unit, Peoria, IL 61604, USA
| | - Megan E Willhoit
- School of Biological Sciences, Illinois State University, Normal, IL 61790 USA US Department of Energy Great Lakes Bioenergy Research Center, Madison, WI 53706, USA
| | - Megha Phutane
- School of Biological Sciences, Illinois State University, Normal, IL 61790 USA US Department of Energy Great Lakes Bioenergy Research Center, Madison, WI 53706, USA
| | - John Ralph
- US Department of Energy Great Lakes Bioenergy Research Center, Madison, WI 53706, USA Department of Biochemistry, Wisconsin Energy Institute, University of Wisconsin, Madison, WI 53706, USA
| | - Shawn D Mansfield
- US Department of Energy Great Lakes Bioenergy Research Center, Madison, WI 53706, USA Department of Wood Science, University of British Columbia, Vancouver, V6T 1Z4, Canada
| | - Paul Nicholson
- Department of Crop Genetics, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
| | - John C Sedbrook
- School of Biological Sciences, Illinois State University, Normal, IL 61790 USA US Department of Energy Great Lakes Bioenergy Research Center, Madison, WI 53706, USA
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Petrik DL, Karlen SD, Cass CL, Padmakshan D, Lu F, Liu S, Le Bris P, Antelme S, Santoro N, Wilkerson CG, Sibout R, Lapierre C, Ralph J, Sedbrook JC. p-Coumaroyl-CoA:monolignol transferase (PMT) acts specifically in the lignin biosynthetic pathway in Brachypodium distachyon. Plant J 2014; 77:713-26. [PMID: 24372757 PMCID: PMC4282527 DOI: 10.1111/tpj.12420] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Revised: 12/16/2013] [Accepted: 12/18/2013] [Indexed: 05/17/2023]
Abstract
Grass lignins contain substantial amounts of p-coumarate (pCA) that acylate the side-chains of the phenylpropanoid polymer backbone. An acyltransferase, named p-coumaroyl-CoA:monolignol transferase (OsPMT), that could acylate monolignols with pCA in vitro was recently identified from rice. In planta, such monolignol-pCA conjugates become incorporated into lignin via oxidative radical coupling, thereby generating the observed pCA appendages; however p-coumarates also acylate arabinoxylans in grasses. To test the authenticity of PMT as a lignin biosynthetic pathway enzyme, we examined Brachypodium distachyon plants with altered BdPMT gene function. Using newly developed cell wall analytical methods, we determined that the transferase was involved specifically in monolignol acylation. A sodium azide-generated Bdpmt-1 missense mutant had no (<0.5%) residual pCA on lignin, and BdPMT RNAi plants had levels as low as 10% of wild-type, whereas the amounts of pCA acylating arabinosyl units on arabinoxylans in these PMT mutant plants remained unchanged. pCA acylation of lignin from BdPMT-overexpressing plants was found to be more than three-fold higher than that of wild-type, but again the level on arabinosyl units remained unchanged. Taken together, these data are consistent with a defined role for grass PMT genes in encoding BAHD (BEAT, AHCT, HCBT, and DAT) acyltransferases that specifically acylate monolignols with pCA and produce monolignol p-coumarate conjugates that are used for lignification in planta.
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Affiliation(s)
- Deborah L Petrik
- School of Biological Sciences, Illinois State UniversityNormal, IL, 61790, USA
- Department of Energy Great Lakes Bioenergy Research CenterMadison, WI, 53706, USA
| | - Steven D Karlen
- Department of Biochemistry, The Department of Energy's Great Lakes Bioenergy Research Center, The Wisconsin Energy Institute, University of WisconsinMadison, WI, 53726, USA
| | - Cynthia L Cass
- School of Biological Sciences, Illinois State UniversityNormal, IL, 61790, USA
- Department of Energy Great Lakes Bioenergy Research CenterMadison, WI, 53706, USA
| | - Dharshana Padmakshan
- Department of Biochemistry, The Department of Energy's Great Lakes Bioenergy Research Center, The Wisconsin Energy Institute, University of WisconsinMadison, WI, 53726, USA
| | - Fachuang Lu
- Department of Biochemistry, The Department of Energy's Great Lakes Bioenergy Research Center, The Wisconsin Energy Institute, University of WisconsinMadison, WI, 53726, USA
| | - Sarah Liu
- Department of Biochemistry, The Department of Energy's Great Lakes Bioenergy Research Center, The Wisconsin Energy Institute, University of WisconsinMadison, WI, 53726, USA
| | - Philippe Le Bris
- INRA, Institut Jean-Pierre Bourgin (IJPB) UMR1318, Saclay Plant Science78000, Versailles, France
- AgroParisTech, Institut Jean-Pierre Bourgin (IJPB) UMR1318, Saclay Plant Science78000, Versailles, France
| | - Sébastien Antelme
- INRA, Institut Jean-Pierre Bourgin (IJPB) UMR1318, Saclay Plant Science78000, Versailles, France
- AgroParisTech, Institut Jean-Pierre Bourgin (IJPB) UMR1318, Saclay Plant Science78000, Versailles, France
| | - Nicholas Santoro
- Department of Energy's Great Lakes Bioenergy Research Center, Michigan State UniversityEast Lansing, MI, 48824, USA
| | - Curtis G Wilkerson
- Department of Plant Biology, Department of Biochemistry and Molecular Biology, Department of Energy's Great Lakes Bioenergy Research Center, Michigan State UniversityEast Lansing, MI, 48824, USA
| | - Richard Sibout
- INRA, Institut Jean-Pierre Bourgin (IJPB) UMR1318, Saclay Plant Science78000, Versailles, France
- AgroParisTech, Institut Jean-Pierre Bourgin (IJPB) UMR1318, Saclay Plant Science78000, Versailles, France
| | - Catherine Lapierre
- INRA, Institut Jean-Pierre Bourgin (IJPB) UMR1318, Saclay Plant Science78000, Versailles, France
- AgroParisTech, Institut Jean-Pierre Bourgin (IJPB) UMR1318, Saclay Plant Science78000, Versailles, France
| | - John Ralph
- Department of Biochemistry, The Department of Energy's Great Lakes Bioenergy Research Center, The Wisconsin Energy Institute, University of WisconsinMadison, WI, 53726, USA
| | - John C Sedbrook
- School of Biological Sciences, Illinois State UniversityNormal, IL, 61790, USA
- Department of Energy Great Lakes Bioenergy Research CenterMadison, WI, 53706, USA
- *(e-mail )
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Huang HH, Day L, Cass CL, Ballou DP, Williams CH, Williams DL. Investigations of the catalytic mechanism of thioredoxin glutathione reductase from Schistosoma mansoni. Biochemistry 2011; 50:5870-82. [PMID: 21630672 DOI: 10.1021/bi200107n] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Thioredoxin glutathione reductase from Schistosoma mansoni (SmTGR) catalyzes the reduction of both thioredoxin and glutathione disulfides (GSSG), thus playing a crucial role in maintaining redox homeostasis in the parasite. In line with this role, previous studies have demonstrated that SmTGR is a promising drug target for schistosomiasis. To aid in the development of efficacious drugs that target SmTGR, it is essential to understand the catalytic mechanism of SmTGR. SmTGR is a dimeric flavoprotein in the glutathione reductase family and has a head-to-tail arrangement of its monomers; each subunit has the components of both a thioredoxin reductase (TrxR) domain and a glutaredoxin (Grx) domain. However, the active site of the TrxR domain is composed of residues from both subunits: FAD and a redox-active Cys-154/Cys-159 pair from one subunit and a redox-active Cys-596'/Sec-597' pair from the other; the active site of the Grx domain contains a redox-active Cys-28/Cys-31 pair. Via its Cys-28/Cys-31 dithiol and/or its Cys-596'/Sec-597' thiol-selenolate, SmTGR can catalyze the reduction of a variety of substrates by NADPH. It is presumed that SmTGR catalyzes deglutathionylation reactions via the Cys-28/Cys-31 dithiol. Our anaerobic titration data suggest that reducing equivalents from NADPH can indeed reach the Cys-28/Cys-31 disulfide in the Grx domain to facilitate reductions effected by this cysteine pair. To clarify the specific chemical roles of each redox-active residue with respect to its various reactivities, we generated variants of SmTGR. Cys-28 variants had no Grx deglutathionylation activity, whereas Cys-31 variants retained partial Grx deglutathionylation activity, indicating that the Cys-28 thiolate is the nucleophile initiating deglutathionylation. Lags in the steady-state kinetics, found when wild-type SmTGR was incubated at high concentrations of GSSG, were not present in Grx variants, indicating that this cysteine pair is in some way responsible for the lags. A Sec-597 variant was still able to reduce a variety of substrates, albeit slowly, showing that selenocysteine is important but is not the sole determinant for the broad substrate tolerance of the enzyme. Our data show that Cys-520 and Cys-574 are not likely to be involved in the catalytic mechanism.
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Affiliation(s)
- Hsin-Hung Huang
- Department of Microbiology and Immunology, Rush University Medical Center, Chicago, Illinois 60612, United States
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Lea WA, Jadhav A, Rai G, Sayed AA, Cass CL, Inglese J, Williams DL, Austin CP, Simeonov A. A 1,536-well-based kinetic HTS assay for inhibitors of Schistosoma mansoni thioredoxin glutathione reductase. Assay Drug Dev Technol 2008; 6:551-5. [PMID: 18665782 DOI: 10.1089/adt.2008.149] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract: Schistosomiasis is a major neglected tropical disease that currently affects over 200 million people and leads to over 200,000 annual deaths. Schistosoma mansoni parasites survive in humans in part because of a set of antioxidant enzymes that continuously degrade reactive oxygen species produced by the host. A principal component of this defense system has been recently identified as thioredoxin glutathione reductase (TGR), a parasite-specific enzyme that combines the functions of two human counterparts, glutathione reductase and thioredoxin reductase, and as such this enzyme presents an attractive new target for anti-schistosomiasis drug development. Herein, we present the development of a highly miniaturized and robust screening assay for TGR. The 5-mul final volume assay is based on the Ellman reagent [5,5'-dithiobis(2-nitrobenzoic acid) (DTNB)] and utilizes a high-speed absorbance kinetic read to minimize the effect of dust, absorbance interference, and meniscus variation. This assay is further applicable to the testing of other redox enzymes that utilize DTNB as a model substrate.
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Affiliation(s)
- Wendy A Lea
- NIH Chemical Genomics Center, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
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Cass CL, Johnson JR, Califf LL, Xu T, Hernandez HJ, Stadecker MJ, Yates JR, Williams DL. Proteomic analysis of Schistosoma mansoni egg secretions. Mol Biochem Parasitol 2007; 155:84-93. [PMID: 17644200 PMCID: PMC2077830 DOI: 10.1016/j.molbiopara.2007.06.002] [Citation(s) in RCA: 144] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2007] [Revised: 06/08/2007] [Accepted: 06/11/2007] [Indexed: 01/06/2023]
Abstract
Schistosomiasis remains a largely neglected, global health problem. The morbid pathology of the disease stems from the host's inflammatory response to parasite eggs trapped in host tissues. Long term host/parasite survival is dependent upon the successful modulation of the acute pathological response, which is induced by egg antigens. In this study, using Multidimensional Protein Identification Technology, we identified the Schistosoma mansoni egg secretome consisting of 188 proteins. Notably we identified proteins involved in redox balance, molecular chaperoning and protein folding, development and signaling, scavenging and metabolic pathways, immune response modulation, and 32 novel, previously uncharacterized schistosome proteins. We localized a subset of previously characterized schistosome proteins identified in egg secretions in this study, to the surface of live S. mansoni eggs using the circumoval precipitin reaction. The identification of proteins actively secreted by live schistosome eggs provides important new information for understanding immune modulation and the pathology of schistosomiasis.
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Affiliation(s)
- Cynthia L Cass
- Department of Biological Sciences, Illinois State University, Normal, IL 61790-4120, United States
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Shen J, Zu K, Cass CL, Beyer AL, Hirsh J. Exon skipping by overexpression of a Drosophila heterogeneous nuclear ribonucleoprotein in vivo. Proc Natl Acad Sci U S A 1995; 92:1822-5. [PMID: 7892184 PMCID: PMC42374 DOI: 10.1073/pnas.92.6.1822] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Heterogeneous nuclear ribonucleoproteins (hnRNPs) are abundant RNA-binding proteins that are implicated in splicing regulation. Here we investigate the role of a Drosophila hnRNP in splicing regulation in living animals. We find that overexpression of the Drosophila hnRNP HRB98DE leads to skipping of all internal exons in the Drosophila dopa decarboxylase (Ddc) pre-mRNA in vivo. These results indicate that HRB98DE has a splicing activity that promotes use of terminal splice sites. The effect of excess HRB98DE on Ddc splicing is transient, even though high levels of HRB98DE persist for at least 24 hr. This suggests that Drosophila larvae can induce a compensating mechanism to counteract the effects of excess HRB98DE.
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Affiliation(s)
- J Shen
- Department of Biology, University of Virginia, Charlottesville 22903
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Amero SA, Raychaudhuri G, Cass CL, van Venrooij WJ, Habets WJ, Krainer AR, Beyer AL. Independent deposition of heterogeneous nuclear ribonucleoproteins and small nuclear ribonucleoprotein particles at sites of transcription. Proc Natl Acad Sci U S A 1992; 89:8409-13. [PMID: 1388268 PMCID: PMC49929 DOI: 10.1073/pnas.89.18.8409] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The major nuclear ribonucleoproteins (RNPs) involved in pre-mRNA processing are classified in broad terms either as small nuclear RNPs (snRNPs), which are major participants in the splicing reaction, or heterogeneous nuclear RNPs (hnRNPs), which traditionally have been thought to function in general pre-mRNA packaging. We obtained antibodies that recognize these two classes of RNP in Drosophila melanogaster. Using a sequential immunostaining technique to compare directly the distribution of these RNPs on Drosophila polytene chromosomes, we found that the two patterns were very similar qualitatively but not quantitatively, arguing for the independent deposition of the two RNP types and supporting a role for hnRNP proteins, but not snRNPs, in general transcript packaging.
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Affiliation(s)
- S A Amero
- Department of Microbiology, University of Virginia School of Medicine, Charlottesville 22908
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