www.czu.cz ; www.usab-tm.ro ; www.raupp.info
On a March day trucks full of burnt cane stalks dot the lonely road to the
sugar mill and the smell of molasses moves with the wind, March 2005 by
Bulldozers scoop bits of this year's processed harvest ? a 70,000-ton
mountain of raw sugar ? onto barges bound for Louisiana refineries.
Half the pile will sit in warehouses, underpriced by foreign competitors and
stalled by federal quotas.
It's a bleak scene for farmers, but a Texas A&M molecular biologist offers
hope. Erik Mirkov has genetically engineered sugar cane with a human gene to
produce a human therapeutic protein. Such a protein could replace the need
to farm cadavers for face-plumping collagen and provide a more affordable
alternative to fermenting hamster cells for cancer treatments.
It also could turn some varieties of Texas sugar into a more profitable
crop. Some proteins used by pharmaceutical companies now are selling for
more than $1 million a gram.
But the research worries environmentalists, who fear the proteins from such
"pharma plants" may somehow get loose and contaminate conventionally grown
food crops. A number of scientists are raising crops spliced with human
genes, which coax the plants to produce proteins that then are extracted and
turned into drugs known as biologics, which Mirkov said would be easier to
produce and less expensive than conventional pharmaceuticals.
One cancer drug being tested now at Stanford University is derived from the
tobacco plant, while other suitable crops include corn and rice.
But Mirkov said sugar cane's simple genetic makeup compared to other crops
would make the splicing with human genes easier and less expensive.
By comparison, he cited his wife's successful treatment of non-Hodgkins
lymphoma with a protein-based drug called Rituxan, which at the time cost
$8,000 for one treatment. His wife needed eight.
Rituxan, manufactured by Genentech Inc., latches on to cancer cells so that
the body will destroy them. The same principles are behind hundreds of drugs
being used against other ailments including breast cancer, rheumatoid
arthritis, and Crohn's disease.
By the time his wife's cancer was being treated with Rituxan, Mirkov was
already well under way with his research and was confident plants could be
used to make the treatments more plentiful and less expensive. And while the
proteins need an expensive purification process, Mirkov said sugar cane's
simple makeup compared to other crops would ease the process.
Most protein-based drugs are made from animal cells, which are reproduced by
fermentation in 10,000-liter vats that are costly to build. The vats
available are working near capacity, Mirkov said. The only capital cost
involved with creating sugar-derived drugs is the cost of planting the
"People have turned to plants as a biofactory," he said, although it could
be years before the proteins are ready for use.
He said similar research on sugar cane is being done in Hawaii. But the
global environmental concerns persist.
Prodigene Inc., of College Station, Texas, successfully made protein from
corn they grew in Nebraska. But when the field was cleared to prepare to
grow soybeans, some of the engineered corn poked through, causing a
bioengineering scare. Some 3 million bushels of soybeans already harvested
had to be incinerated. Ingesting a genetically altered crop can be fatal,
Neil Carman, with the Sierra Club's national genetic engineering committee,
warned that entire European and other markets ? as well as some U.S.
manufacturers ? might reject Texas sugar.
"Somebody buying it may say 'we don't want any collagen in the sugar cane
we're buying ... we don't want any sugar cane if it's growing in an area
where there's some kind of genetically engineered crop, he said.
"There's just a lot of unanswered questions here. The science is still brand
new and we need a lot more testing and research and studies before this
stuff should really be put out into the field."
But sugar cane propagates without seed and because U.S.-grown sugar stalks
are "tough as a two-by-four" in Mirkov's words, it's unlikely to be chewed
as is common in other countries.
For now, the super sugarcane grows in greenhouses at Texas A&M. Some
transgenic sugarcane resistant to insects, viruses and herbicides is growing
in experimental fields around the Rio Grande Valley. While Mirkov is trying
to increase the amount of protein each plant produces, right now it would
take 9,000 acres of sugar cane to make a ton of protein for use by drug
companies ? for some existing cancer treatments enough to treat 150,000
Having a market for that much sugar cane would be welcome news for sugar
Sugar was brought to the Rio Grande Valley in the late 19th century and
rooted quickly. At Texas sugar's height, the Valley had five mills. But
before long, sugar was being produced more cheaply in the Caribbean and
other places, and by 1921, the last of the mills shut down.
In the early 1970s, as America's sugar consumption soared, it became the
Valley's comeback crop. Although some say the crop is too thirsty for the
region, it returns more than cotton, and is less fragile than citrus.
Growers formed a cooperative to build and operate the only cane mill now
operating in Texas.
"Mass produced candies, cakes, sodas ? then, there wasn't enough," said
Humberto Vela, the mill director.
The mill has produced 1.5 million tons of raw sugar since the 1970s ? a
fraction of what is produced in Florida, Louisiana or Hawaii.
Farmers get their orders at the start of five-year cycles, which is how they
ended up producing more than the government allowed.
Five years ago, the region was in severe drought and farmers couldn't make
tonnage. Last year the cooperative was unable to sell 36,000 tons.
The answer now seems to be selling the land or switching the crop, but the
sugar growers are keeping tabs on Mirkov's research.
Growers just want to sell their sugarcane, Vela said, whether for medicines
or breakfast cereals. So if science is the new market for sugar cane, Vela
said, that's fine with them.
"On a level playing field our farmers can compete with anybody in the
world," he said. "But I'm going to assume that until the research shows
there's something really good they'll be reluctant to jump in ? because they
lost so many times."
Posted to Phorum via PhorumMail