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
 Dairy and Functional Foods Research: Wyndmoor, PA
 close



    Research

                    Research Projects
                                    Publications
                                    Collaborations
                                    News
                People

                    Staff Listing
                                    Careers


        


                    About ERRC
                        Greetings from the Director
                                    Directions/Lodging
                                    History and Accomplishments
                    Our Work
                        Biomass Pyrolysis Research
                                    IPMP 2013
                                    IPMP Dynamic Prediction
                                    IPMP Global Fit
                                    Pathogen Modeling Program (PMP)
                                    Predictive Microbiology Information Portal (PMIP)
                                    PoultryFARMSearch small
                    Search
            
            ARS Home
                                About ARS
                                Contact Us




ARS Home Northeast Area Wyndmoor, Pennsylvania Eastern Regional Research Center Dairy and Functional Foods Research 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
                                            Renye, Johnitem
                                            Somkuti, George
  Submitted to: Biotechnology Letters
                                    Publication Type: Peer Reviewed Journal
                                    Publication Acceptance Date: 11/19/2011
                                    Publication  Date: 3/1/2012
                                    Citation: Renye Jr, J.A., Somkuti, G.A. 2012. Vector-mediated chromosomal integration of the glutamate decarboxylase gene in streptococcus thermophilus. Biotechnology Letters. 34:549-555.Interpretive Summary: Gamma-aminobutyric acid (GABA) is a potent neurotransmitter shown to induce relaxation, reduce anxiety, and lower blood pressure in humans.  Some lactic acid bacteria (LAB), commonly used in the production of dairy foods, have been shown to naturally produce GABA and are considered potential probiotics for use in the development of functional foods.  However, GABA production is limited to specific strains of these bacteria, thus the use of microbial biotechnology was investigated for its potential to transfer of this activity to non-producing LAB.  In this study, the gene which encodes glutamate decarboxylase, an enzyme essential for the production of GABA, was transferred to a strain of Streptococcus thermophilus that does not produce GABA.  Following transfer of the gene, it was shown that the newly developed bacterium produced amounts of GABA similar to those observed from a known GABA producing strain of S. thermophilus.  This method of transfer is expected to allow the bacterium to maintain its food-grade status, while improving its potential to serve as a probiotic for improving the health-promoting properties of dairy foods.
                                Technical Abstract: The integrative vector pINTRS was used to transfer glutamate decarboxylase (GAD) activity to Streptococcus thermophilus ST128, thus allowing for the production of '-aminobutyric acid (GABA).  In pINTRS, the gene encoding glutamate decarboxylase, gadB, was flanked by DNA fragments homologous to a S. thermophilus pseudogene to allow for integration at a non-essential locus on the chromosome.  Screening techniques confirmed the insertion of gadB with either its endogenous promoter or the S. thermophilus P2201 promoter, resulting in the generation of recombinant strains, ST128/gadB or ST128/P2201-gadB.  Following the integration event it was shown that unwanted plasmid DNA, specifically the erythromycin resistance gene, was eliminated from the recombinant strains. Based on the production of GABA, both strains displayed similar levels of GAD activity ( 23.0 – 23.8 uM/mg of dry cell weight).


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