Gregory Stephanopoulos, Ph.D.

Five MIT faculty elected to the National Academy of Sciences for 2023

Joshua Angrist, Gang Chen, Catherine Drennan, Dina Katabi, and Gregory Stephanopoulos are recognized by their peers for their outstanding contributions to research.

The National Academy of Sciences has elected 120 members and 23 international members, including five faculty members from MIT. Joshua Angrist, Gang Chen, Catherine Drennan, Dina Katabi, and Gregory Stephanopoulos were elected in recognition of their “distinguished and continuing achievements in original research.” Membership to the National Academy of Sciences is one of the highest honors a scientist can receive in their career… Continue reading.

Boosting production of biofuels such as ethanol could be an important step toward reducing global consumption of fossil fuels. However, ethanol production is limited in large part by its reliance on corn, which isn’t grown in large enough quantities to make up a significant portion of U.S. fuel needs.

To try to expand biofuels’ potential impact, a team of MIT engineers has now found a way to expand the use of a wider range of nonfood feedstocks to produce such fuels. At the moment, feedstocks such as straw and woody plants are difficult to use for biofuel production  because they first need to be broken down to fermentable sugars, a process that releases numerous byproducts that are toxic to yeast, the microbes most commonly used to produce biofuels… Continue reading.

The Society for Biological Engineering (SBE) has announced that its chair, Professor Gregory Stephanopoulos of the Massachusetts Institute of Technology (MIT), has received the 2013 John Fritz Medal. The award, presented by the American Association of Engineering Societies (AAES), recognizes Stephanopoulos’ defining contributions to the field of metabolic engineering and the bio-based economy. Many consider the Fritz Medal, established in 1902, to be the highest award in the engineering profession. It is presented for “outstanding scientific or industrial achievements.”

In the search for renewable alternatives to gasoline, heavy alcohols such as isobutanol are promising candidates. Not only do they contain more energy than ethanol, but they are also more compatible with existing gasoline-based infrastructure. For isobutanol to become practical, however, scientists need a way to reliably produce huge quantities of it from renewable sources.

MIT chemical engineers and biologists have now devised a way to dramatically boost isobutanol production in yeast, which naturally make it in small amounts. They engineered yeast so that isobutanol synthesis takes place entirely within mitochondria, cell structures that generate energy and also host many biosynthetic pathways. Using this approach, they were able to boost isobutanol production by about 260 percent.

Though still short of the scale needed for industrial production, the advance suggests that this is a promising approach to engineering not only isobutanol but other useful chemicals as well, says Gregory Stephanopoulos, an MIT professor of chemical engineering and one of the senior authors of a paper describing the work in the Feb. 17 online edition of Nature Biotechnology.

Cancer cells usually live in an environment with limited supplies of the nutrients they need to proliferate — most notably, oxygen and glucose. However, they are still able to divide uncontrollably, producing new cancer cells.

A new study from researchers at MIT and the Massachusetts General Hospital (MGH) Cancer Center helps to explain how this is possible. The researchers found that when deprived of oxygen, cancer cells (and many other mammalian cells) can engage an alternate metabolic pathway that allows them to use glutamine, a plentiful amino acid, as the starting material for synthesizing fatty molecules known as lipids. These lipids are essential components of many cell structures, including cell membranes.

The finding, reported in the Nov. 20 online edition of Nature, challenges the long-held belief that cells synthesize most of their lipids from glucose, and raises the possibility of developing drugs that starve tumor cells by cutting off this alternate pathway.

Lead author of the paper is Christian Metallo, a former postdoc in the lab of Gregory Stephanopoulos, the William Henry Dow Professor of Chemical Engineering and Biotechnology at MIT and a corresponding author of the paper. Othon Iliopoulos, an assistant professor of medicine at Harvard Medical School and MGH, is the paper’s other corresponding author.

The Biotechnology Industry Organization (BIO) today presented the annual George Washington Carver Award for Innovation in Industrial Biotechnology to Gregory Stephanopoulos, the Willard Henry Dow Professor of Chemical Engineering at Massachusetts Institute of Technology, recognizing his pioneering work in the field of industrial biotechnology and in particular metabolic engineering and its practical application to industrial processes. The award was presented at a plenary session during the 2010 World Congress on Industrial Biotechnology and Bioprocessing, in Washington, D.C.

Throughout human history, plants have been a source of potent medicines, including many cancer drugs discovered over the past few decades. However, it is quite difficult to discover such drugs and obtain them in large quantities from the plants or through chemical synthesis.

MIT researchers and collaborators from Tufts University have now engineered E. coli bacteria to produce large quantities of a critical compound that is a precursor to the cancer drug Taxol, originally isolated from the bark of the Pacific yew tree. The bacteria can produce 1,000 times more of the precursor, known as taxadiene, than any other engineered microbial strain.

The technique, described in the Oct. 1 issue of Science, could bring down the manufacturing costs of Taxol and also help scientists discover potential new drugs for cancer and other diseases such as hypertension and Alzheimer’s, said Gregory Stephanopoulos, who led the team of MIT and Tufts researchers and is one of the senior authors of the paper.