NEWS OF THE W EEK
ANOTHER U.S. CRACKER PLANNED PETROCHEMICALS: Formosa eyes a massive new petrochemical complex in Louisiana, as another project advances CRACKLE North
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American ethylene capacity additions are expected to peak in 2018.
VEN AFTER A DOZEN FIRMS have announced
multi-billion-dollar U.S. ethylene cracker projects, the rush to build petrochemical plants to take advantage of cheap and plentiful shale gas shows no sign of abating. Millions of metric tons per year Formosa Petrochemical, a subsidiary of 6 Taiwan’s Formosa Plastics, has launched a 5 feasibility study for a $9.4 billion complex 4 in St. James, La. The project was unveiled through the office of Louisiana Gov. Bobby 3 Jindal, a Republican presidential candi2 date, who visited Taiwan last year in a bid to win the project for his state. 1 Formosa envisions a two-stage project. 0 2014 15 16 17 18 19 The first phase would feature an ethaneNOTE: Does not include projects, including based ethylene cracker as well polyethylene, Formosa’s and PTT’s, that were recently ethylene glycol, and other plants. The secannounced and are not fully developed. SOURCE: IHS Chemical ond phase would double capacity.
TOBACCO PLANT HELPS MAKE ANTICANCER DRUG
OH O O
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PLANT BIOLOGY: Modified plant
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CH3O
produces etoposide precursor
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OH
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Etoposide aglycone
OH HO O
O O
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O O O O
CH3O
OCH3
OH Etoposide
ESEARCHERS AT STANFORD UNIVERSITY
have identified enzymes that could make it easier to produce the anticancer drug etoposide (Science 2015, DOI: 10.1126/science.aac7202). Etoposide is currently synthesized from podophyllotoxin, a natural product first isolated from the Himalayan mayapple plant, Podophyllum hexandrum. “Podophyllum is not an easy plant to cultivate and grow,” says Elizabeth S. Sattely, who led the study. “It’s a challenge to sustainably grow the plant to get enough compound.” Such difficulties could be avoided by producing an etoposide precursor in a different, easier-to-handle organism. Sattely and grad student Warren Lau have now identified the enzymes in the mayapple plant that could enable such a move. The pathway comprises 10 genes, four of which were already known. Sattely and Lau found the other C E N. ACS.ORG
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Assuming a final go-ahead, Formosa plans to begin construction next year. Another Formosa subsidiary is already building a new cracker in Point Comfort, Texas, that is slated to open in 2017. Separately, PTT Global Chemical is progressing on its proposed cracker in Mead Township, Ohio. The Thai firm says it plans to spend $100 million on frontend engineering and design. PTT has picked Fluor and Bechtel as contractors and plans to make a final investment decision in 12 months. Ohio Gov. John R. Kasich, who is also running for president, says the project marks a major step for Ohio as a participant in the shale gas revolution. The cracker would be on the site of a coal-fired power plant that was shuttered in 2011. Chuck Carr, senior director of global olefins at the consulting firm IHS Chemical, says local government support is an important consideration in selecting a site for a new plant. “If you are getting tax incentives, that can be helpful,” he says. “And it goes a long way toward getting community support.” Overall, Carr expects 11 million metric tons per year of new ethylene capacity to be added in North America through 2019, a 30% increase over current levels. He sees plenty of shale gas feedstock to supply the new plants—and even enough for another wave of projects that could hit the market by 2025.—ALEX TULLO
six genes by searching the RNA produced by wounded mayapple plants, which make extra deoxypodophyllotoxin, a proposed podophyllotoxin precursor, in response to being wounded. The team used bacterial plasmids to transfer the pathway into Nicotiana benthamiana, a wild relative of tobacco plants that’s easy to grow. The pathway the researchers assembled has an unexpected bonus. It contains two enzymes that convert deoxypodophyllotoxin into the etoposide aglycone, which differs from etoposide only in that it lacks a disaccharide group. The aglycone also requires fewer steps to convert into etoposide than does podophyllotoxin. Currently, the engineered tobacco plants produce only nanogram amounts of the etoposide precursor. Although she thinks the task will be challenging, Sattely plans to engineer the new pathway into yeast, a prolific microorganism, to improve the yield. The work is interesting and timely, but there’s a long way to go before significant amounts of the precursor could be obtained from tobacco, says Norman G. Lewis, an expert on plant metabolic engineering at Washington State University. “The amounts presently described are tiny, and there will be significant technical hurdles to overcome to get this into a commercially viable system in either tobacco or yeast,” he says. “The problems they will face on this, however, are common to everyone” in metabolic engineering and synthetic biology.—CELIA ARNAUD
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