Navigation Links
Kilogram quantities at last!
Date:2/4/2008

The citric acid cycle, one of the most important metabolic processes in our bodies, was formulated in 1937. Since then, all of the intermediates have been produced in multigram quantitieswith one exception, (2R,3S)-isocitric acid. Athanassios Giannis and his team at the University of Leipzig have finally done it. As they report in the journal Angewandte Chemie, their process, a combination of one biotechnological and one chemical step, starts with sunflower oil, a renewable starting material. Isocitric acid and its derivatives thus become accessible on a kilogram scale.

In the citric acid cycle, acetyl CoA, formed in the breakdown of lipids, sugars, and amino acids, is used to produce energy that is biochemically available to an organism. Carbon dioxide and water are produced in this process. This reaction mechanism is named after one of the intermediate products, the anion of citric acid.

In nature, isocitric acid is always found with its isomer, citric acid. The difference between these two compounds is merely that the hydroxy group (-OH) is bound to a different carbon atom of each molecule. Large-scale separation of the two isomers has not been possible. A fermentative synthesis of the pure compound has also not worked.

Giannis team has now finally done it, thanks to a host of tiny helpers, the yeast Yarrowia lipolytica, which produces isocitrate from refined sunflower oil in previously unachievable yield and in a favorable isocitrate to citrate ratio. After the biomass is filtered out, electrodialysis is used to obtain the pure acids. The researchers use a trick to separate citric acid from isocitric acid: They use methanol to convert the compounds into the corresponding methyl esters. Why does this work" Whereas the citric acid ester crystallizes, the isocitric acid ester is a liquid. Separation then becomes childs play.

Why was isocitric acid so important to these researchers" Isocitric acid is a compound with chiral centerscarbon atoms with four different groups bound to them. There are always two versions of a chiral center, one being the mirror image of the other. Smaller, easily accessible chiral compounds are useful building blocks for the synthesis of complex natural products and are interesting starting materials for the pharmaceutical industry. Isocitric acid makes available a new assortment of such chiral building blocks.


'/>"/>

Contact: Athanassios Giannis
giannis@uni-leipzig.de
49-341-973-6581
Wiley-Blackwell
Source:Eurekalert

Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/22/2016)... , June 22, 2016   Acuant ... and verification solutions, has partnered with RightCrowd ... solutions for Visitor Management, Self-Service Kiosks and ... products that add functional enhancements to existing ... corporations and venues with an automated ID ...
(Date:6/15/2016)... New York , June 15, 2016 /PRNewswire/ ... a new market report titled "Gesture Recognition Market by ... and Forecast, 2016 - 2024". According to the report, ... USD 11.60 billion in 2015 and is estimated ... reach USD 48.56 billion by 2024.  ...
(Date:6/2/2016)... The Department of Transport Management (DOTM) of ... project, for the , Supply and Delivery of ... Infrastructure , to Decatur , ... Management Solutions. Numerous renowned international vendors participated in the tendering ... selected for the most compliant and innovative solution. The contract ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... June 23, 2016  The Prostate Cancer Foundation (PCF) is pleased ... and faster cures for prostate cancer. Members of the Class of 2016 were ... Read More About the Class of 2016 PCF Young ... ... ...
(Date:6/23/2016)... 23, 2016   EpiBiome , a precision microbiome ... in debt financing from Silicon Valley Bank (SVB). The ... to advance its drug development efforts, as well as ... "SVB has been an incredible strategic partner to ... traditional bank would provide," said Dr. Aeron Tynes ...
(Date:6/23/2016)... ... ... STACS DNA Inc., the sample tracking software company, today announced that Dr. ... STACS DNA as a Field Application Specialist. , “I am thrilled that Dr. ... STACS DNA. “In further expanding our capacity as a scientific integrator, Hays brings a ...
(Date:6/23/2016)... 23, 2016 Apellis Pharmaceuticals, Inc. today ... trials of its complement C3 inhibitor, APL-2. The ... ascending dose studies designed to assess the safety, ... injection in healthy adult volunteers. Forty ... a single dose (ranging from 45 to 1,440mg) ...
Breaking Biology Technology: