U.S. flagAn official website of the United States government
                    Here's how you know **Official websites use .gov**
                            
                            A **.gov** website belongs to an official government organization in the United States.
 **Secure .gov websites use HTTPS**
                            
                            A **lock** (                            
                              A locked padlock                                                      
                            
                            ) or **https://** means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.


Menu Agricultural Research Service
						
                    U.S. DEPARTMENT OF AGRICULTURE
 close



Research
                Research Home
                            National Programs
                            Research Projects
                            Scientific Manuscripts
                            International Engagement
                            Scientific Software/Models
                            Databases and Datasets
                            Office of Scientific Quality Review
            Media
                News & Features
                            Multimedia
                            Briefing Room
                            Down on the Farm
                            Press Room
                            Science in Your Shopping Cart
                            Scientific Discoveries
                            Tellus
                            Under the Microscope
            About ARS
                About ARS Home
                            Staff Directory
                            Labs and Research Centers (Map)
                            Headquarter Offices
                            Organizational Chart
                            Employee Services (REE Employees Only)
                            Office of Outreach, Diversity, and Equal Opportunity
            Work With Us
                Work With Us Home
                            ARS Vacancies at USAJOBS
                            Careers at ARS Information
                            Scientific Collaborations
                            Extramural Agreements
                            1890 Faculty Research Sabbatical ProgramSearch small
                    Search
            
            ARS Home
                                About ARS
                                Contact Us




ARS Home Research Publications at this Location





- ARS National Programs
- Search for a scientific manuscript
- Search for a research project
- ARS Software
- Programs and Projects
- Collaborations
- Subjects of Investigation
- Publications

Title:   Author  item
                                            Alexander, Nancyitem
                                            McCormick, Susanitem
                                            Proctor, Robert
  Submitted to: Meeting Abstract
                                    Publication Type: Abstract Only
                                    Publication Acceptance Date: 4/20/2004
                                    Publication  Date: 4/20/2004
                                    Citation: Alexander, N.J., Mc Cormick, S.P., Proctor, R. 2004. Heterologous expression of the fusarium graminearum tri4 gene in f. verticillioides provides evidence for a multifunctional oxygenase in trichothecene biosynthesis. Meeting Abstract.Interpretive Summary:
                                Technical Abstract: The biosynthesis of trichothecene mycotoxins by Fusarium sporotrichioides and F. graminearum involves a complex biochemical pathway that begins with the cyclization of farnesyl pyrophosphate to the sesquiterpene hydrocarbon trichodiene and continues with multiple oxygenation, cyclization and esterification reactions.  In previous studies using F. sporotrichioides, disruption of the P450 monooxygenase-encoding gene Tri4 blocked trichothecene production and lead to the accumulation of trichodiene.  Therefore, the TRI4 protein must act on trichodiene.  To further elucidate the function of the TRI4 protein, we heterologously expressed the F. graminearum Tri4 (FgTri4) in F. verticillioides, which does not produce trichothecenes.  Transgenic F. verticillioides carrying FgTri4 under the control of a fumonisin biosynthetic gene (FUM8) promoter converted exogenous trichodiene to isotrichodermin.  Conversion of trichodiene to isotrichodermin requires seven biochemical reactions (trichodiene to 2-hydroxytrichodiene to 12,13-Epoxy-9,10-trichoene-2-ol to isotrichodiol to isotrichotriol to trichotriol to isotrichodermol to isotrichodermin).  Previous studies indicate that two of these reactions (isotrichotriol to trichotriol to isotrichodermol) are non-enzymatic, and feeding studies done here indicate that wild-type F. verticillioides can convert isotrichodermol to isotrichodermin.  Together, these results indicate that the FgTri4 protein is a multifunctional monooxygenase that catalyzes the four oxygenation reactions required for the conversion of trichodiene to isotrichotriol during trichothecene biosynthesis.


Return to top


Connect with ARS Sign up


ARS Home
                            USDA.gov
                            Plain Writing
                            Policies & Links
                            Civil Rights Statements
                            FOIA
                            Accessibility Statement
                            Privacy Policy
                            Non-Discrimination Statement
                            Quality of Information
                            USA.gov
                            WhiteHouse.gov