Biochemical understanding of how plants regulate oil synthesis could point to new strategies for producing renewable energy-rich chemicals
Scientists studying plant biochemistry at the U.S. Department of Energy’s Brookhaven National Laboratory have discovered new details about biomolecules that put the brakes on oil production. The findings suggest that disabling these biomolecular brakes could push oil production into high gear—a possible pathway toward generating abundant biofuels and plant-derived bioproducts. The study appears in in the journal Plant Physiology.
“It’s normal for plant cells to down-regulate oil production when we feed them excess fatty acids, and this study confirms our hypothesis about how they do that. But we also discovered that the brakes on oil production are partially on even under normal conditions, which was a big surprise,” said Brookhaven Lab biochemist John Shanklin, who led the research.
“It would be like driving a car for several years and finding out one day that a parking brake you didn’t know about had been on all along. When you remove that brake, the car has much more power; that’s what we’ve just discovered for plant oil production,” he said.
A delicate balance
The biomolecule central to this study is the enzyme that determines the rate of oil production. That enzyme, known as ACCase, is a protein made of four subunits, all of which are necessary for the enzyme to function. With all four subunits in place, the enzyme drives the first step in the synthesis of fatty acids, key components of oils.
Earlier work by Shanklin’s group in 2012 revealed that when plant cells were fed a short-term excess of fatty acids (lasting less than two days), a feedback loop inhibited this enzyme, so oil production would slow down. As long as fatty acid concentrations dropped within two days, the enzyme and oil production would turn back on. But a longer-term excess of fatty acids would permanently disable the enzyme. At the time, scientists knew of several ways that the enzyme could be inhibited, but none of those ways could explain the irreversible inhibition they were observing.
We discovered that the brakes on oil production are partially on even under normal conditions, which was a big surprise.
— Brookhaven Lab biochemist John Shanklin
When colleagues at the University of Missouri discovered an inactive version of one of the four enzyme subunits in 2016, Shanklin suspected that this inactive subunit might be the cause of the permanent shutdown—by taking the place of one of the active subunits in the enzyme. He designed this new study to test that hypothesis.
Team member Hui Liu obtained plants in which the genes that code for the inactive subunits were individually disabled. She used those variants to breed plants that had combinations of disabled subunits. If Shanklin’s idea was correct, cells with disabled inactive subunits would have a lower capacity to turn the enzyme off.
“We suspected that disabling the genes would turn off the off-switch for oil production, allowing the plant cells to make more oil,” Shanklin explained.
When team member Jan Keereetaweep tested this idea by feeding the plant cells excess fatty acids, that’s exactly what happened: Cells with combinations of the disabled genes didn’t turn off oil production the way cells with the normal genes did.
“There was 50 percent less inhibition of oil production in the cells with disabled genes compared to the wild-type plant cells,” Shanklin said. That result confirmed that the inactive subunit coded for by the normal genes in the wild-type plants was indeed what triggered permanent shutdown of the enzyme.
But the big surprise came when Keereetaweep measured fatty acid synthesis in the plant cells with disabled inactive subunits without artificially feeding them excess fatty acids and compared the results with those for wild-type plant cells under the same conditions. Under those normal conditions, where you wouldn’t expect to see oil production inhibited, the enzyme driving oil production was significantly more active in plant cells with the disabled genes than in normal plant cells.
“That means that, even under normal conditions, inactive subunits are putting the brakes on ACCase, reducing its activity and limiting oil production,” Shanklin said. “Disabling the genes for those inactive subunits is like taking the brakes off the car, revealing the motor’s true potential.”
Learn more: Removing the Brakes on Plant Oil Production
The Latest on: Plant oil production
via Google News
The Latest on: Plant oil production
Bio-on inaugurates in Italy the first special bioplastics production plant. 100% natural and biodegradable
on June 20, 2018 at 10:57 am
"Like all complex industrial plants, the new production hub is running a series of tests before ... the bioplastic microbeads for cosmetics designed to replace the oil-based plastic particles currently used, which are harmful and non-biodegradable. […]
Ethane production growth led to record U.S. natural gas plant liquids production in 2017
on June 20, 2018 at 1:28 am
U.S. natural gas plant liquids (NGPL) production has nearly doubled since ... and to a lesser extent by associated natural gas, a byproduct of crude oil production. The high liquids content of many shale plays means that growth in marketed natural ... […]
Record US NGL production in 2017 stemmed from ethane growth - EIA
on June 19, 2018 at 12:37 pm
Associated natural gas, a byproduct of crude oil production, was also cited ... bbl/day of the increase stemming from growth in ethane production. The EIA noted that several petrochemical plants in the US are expected to come online in 2018 and 2019 ... […]
When Rainforest is Cleared for Palm Oil, a Jet Liner of Carbon is Produced
on June 19, 2018 at 12:11 pm
The production of palm oil, the vegetable oil used in thousands of modern products ... “There is more carbon stored below ground in the soil than in plants and the atmosphere combined. As this study shows, the conversion of tropical rainforest to ... […]
Petroteq Unveils Asphalt Ridge Oil Extraction Facility, Initiates Production
on June 19, 2018 at 11:34 am
announced the successful unveiling of its environmentally friendly heavy oil processing and extraction plant located at the Asphalt Ridge in Uintah Basin, Utah. Management of Petroteq took the opportunity of this media day to initiate production at the plant. […]
Palm oil: The carbon cost of deforestation
on June 19, 2018 at 3:02 am
Intensive rubber farming, on the other hand, is associated with a loss of 159 tons of carbon, while extensive rubber production corresponds to 116 tons. This difference between oil palms and rubber plants owes largely to the shorter plantation rotation ... […]
North Slope oil production drops in FY2018
on June 16, 2018 at 11:34 pm
Most of Alaska’s oil production is from the North Slope ... Usually North Slope output drops during the summer months because of the turnarounds and because production plants are less efficient in the warmer weather. The deficits are made up in the ... […]
Oil production surges in April
on June 15, 2018 at 10:00 pm
April oil production surged ahead unexpectedly ... But road restrictions in effect during May and the unplanned outage of a gas plant could pull May’s numbers down. Still, it is all a good indicator that the state will break its old record probably ... […]
As N.D. oil production nears record, natural gas flaring climbs
on June 15, 2018 at 6:01 pm
Helms said an outage at the Robinson Lake gas processing plant in May likely led some companies to limit oil production in order to stay within flaring limits. He tempered expectations about May oil production, but said the state will likely break the oil ... […]
via Bing News