* Why we need GM foods
* Bt cotton in butcher's hand
* Africa seeks agricultural revolution
* Collaboration to Test Drought Resistant Rice
* Man-made protocell hosts DNA synthesis
Why we need GM foods
- Michael Wigan, Daily Telegraph, June 2, 2008
The Government is accused of having lost touch with reality.
No better example exists than agriculture minister Hilary Benn's insistence that domestic food production is unnecessary for food security.
Other countries across the world are protecting their populations from running low; even major food exporters like Argentina are beginning to restrict some exports. American rice rationing is a fact.
World leaders are starting openly to talk about food running out. The sharp commodity price hikes after 10 years of stagnation are causing alarm. China is now seeking to buy farm-land abroad further increasing alarm.
The arguments about genetically modified crops are being resurrected. When the price of a loaf of bread doubles, as it is on the way to doing, the public's pickiness about production methods will weaken.
GM can be seen as crop modification addressing contemporary problems. Take fuel costs and the carbon effects of heavy tractors churning over fields. On a crop of GM sugar-beet or oil seeds weeds are controlled with one 'pass', the tractor using an all-inclusive weed-killer to over-spray the crop which itself remains undamaged. Ordinary sugar-beet varieties require three to four sprayings.Not only is the labour cost quartered, and the cost of the fertiliser quartered, so is the wear and tear on machinery and the need for its replacement. This lighter impact agriculture clicks in down the whole crop cycle. As tractors traverse soil they compact it. Plant roots - wheat has a one metre root - cannot get water and nutrients from deep down. Along comes the sub-soiler, a spike dragged slowly, in low gear, deep into the 'pan', breaking it up again to aereate the soil.
If you only traverse the field once to kill the weeds, compaction is reduced and aggressive sub-soiling needed less often. Less time, less fuel, less labour, lower carbon, and less spray-drift for those who object to farm chemicals.
Fuel cost is one of the main drivers behind re-consideration of GM. We all know it costs more to fill the car. Less well-known is that in every budget since 1997 the taxation cost of red diesel used on farms has closed the gap on ordinary motorists' diesel. Farmers have been a conveniently mute target for the Chancellor's punishment.Added to the fuel spike the figures are dramatic. Accountants Grant Thornton say farmers spent £47 per farm hectare on fuel in 2006 and 2007 harvests. The crop growing in the ground now will have cost £74 a hectare. The urgency of cutting this cost is pressing. If using GM means three to four times less fuel consumption, along with the other environmental and economic benefits, how can British farmers be expected to compete with crops from biotech's cheaper systems on other continents?
Then there is disease. Last year a sizeable part of the potato crop was wasted by blight. GM can protect crops from disease; crops can also be designed better to resist drought, a food supply threat over southern Europe.
Last time GM crop trials were tried in Britain, with maize and sugar-beet, protesters pulled up the plants. Next time the public may view this sabotage of our survival strategy with less indifference. Last time public identification of the trial farms - and targets for the protesters - was compulsory under freedom of information legislation. With some food becoming expensive or unavailable, will we condone so readily this incongruous legal anomaly?
Over half of western Canada's enormous output of grain is grown using 'minimum tillage', a more natural soil-management system which tickles the ground rather than turning it over by ploughing, whilst retaining normal yields.
British farmers are increasingly using min-till on appropriate soils with encouraging results. But, surreally, on being asked about the promotion of min-till here at home, a method capable of addressing headline issues of flooding and soil erosion, the agriculture department seemed unaware of its existence.
Government departments need to wake up to what is going on and engage with the real world. Presently the fastest conversion to min-till is happening in eastern Europe, competitors in our market.
Science magazine, reporting on an international conference about the future role of biotech in agriculture, used the title, 'Dueling visions for a hungry world'. GM and anti-GM points of view are sharply entrenched.
However, if as opponents claim, GM leads to crop reduction and sterilised land, why is it that so many farmers are turning to it? GM is now grown on over 100m hectares globally. The USA has swept ahead with GM as an aid in maximising outputs of maize and soyabeans making food and animal feeds America's largest export. No harmful side effects on American consumers have hitherto been detected, or even claimed.
That is the trigger for a change of view in Europe, which is the world's only large food producer holding out against GM with the support of consumers. If damage to human health was proven, or suspected, Europeans are affluent enough, in the main, to continue as they are, with food becoming a bulkier living cost year on year.
But the refusal to use the biotech tool of modern agriculture, in essence the same as the plant development which has been going on since the first wheat-type plants were discovered by the Assyrians beside the Euphrates, will alter with non-availability of traditional foods. Will Italians prefer modified durrum wheat for their pasta to no pasta?
The small area of Spain, Germany and Portugal in which GM maize is grown today with EU regulatory approval is not controversial. Yet few consumers realise that in imported livestock and poultry they are eating GM-fed animals already.
Virtually all the Argentinian and American soyabean crop has been modified, and Brazil's is rapidly becoming so. This is used to feed chickens, cattle, and pigs prior to slaughter, protein which duly appears on supermarket shelves at lower prices than our home-reared meat fed a costlier diet. No wonder our livestock sector is collapsing.
The acceleration of Europe towards status as a major food importer is contrary to geology and geography. Europe has some of the best arable land anywhere. The cutting-edge revolutions in food production, like rotational copping, occurred here. China, raking the world for food-producing soils elsewhere, has limited arable land, and in the rush for infrastructure growth over ten per cent of the best ground has inadvertently been concreted over.
Soon cavalier attitudes to usable land will change. As was until recently the case, intelligent planning will assess land's ability to grow food before permitting it to be developed. The Council for the Protection of Rural England says we are losing 23 square miles of land a year. Natural England is actually proposing to flood good East Anglian farm-land in favour of creating salt-marsh, a policy viewed with stupefaction by the Dutch who have won back their country from the encroaching sea.
Food sufficiency, the argument will go, demands soil to work and the best of biotechnology to exploit it. The time is advancing when crop yields, at present arcane considerations only for the human earthworms, will be seen as an economic, environmental and consumer benefit.
Bt cotton in butcher's hand
- Ijaz Ahmad Rao, Pakissan.com, June 5, 2008
Agricultural use of genetically modified (GM) crops across the world has increased almost seventy fold in the past ten years and is set to double by 2015, says a study released by The International Service for the Acquisition of Agri-biotech Application, a non-profit organization. It has been estimated that GM crops were planted on 282 million acres worldwide during 2007. At present, 23 countries plant such crops, with a further 29 allowing imports for GM food or GM animal feed. The GM seed industry is dominated by an American company whose seeds are planted on more than 90 per cent of global biotech acreage.
Adoption of Bt cotton has risen dramatically in the world from 1.90 million acres in its introductory period in 1996 to 19.40 millions acres in 2006. Area planted to biotech varieties increased to over one-fourth of the world total in 2005-06, and it is estimated that biotech varieties account for 38 per cent of 86.5 million acres planted to cotton in 2006-07. It is remarkable that in the last cotton growing season 78 per cent of cotton crops grown in USA, 70 per cent in China and 80 per cent in Australia were with single or multiple Bt genes. Where Bt cotton has been adopted, average yield reportedly increased from 10 to 45 per cent while pesticide cost declined by 65 per cent in China, 58 per cent in South Africa, and over 50 per cent in India.
"There will be a doubling of the number of countries involved, a doubling of the number of hectares and the number of farmers involved will rise almost ten fold," said Clive James, chairman and founder of the ISAAA. "At a time when you have soaring commodity prices and sky-rocketing energy prices, you want a technology that will increase the supply side and bring down the cost of production and this is what you have in this technology," he added.
India has reported the highest proportional increase of any biotech crop country in the world with a gain of 63 per cent in 2007. Area under Bt cotton rose from 0.11 million acres in 2002 to some 3.1 million acres in 2005; five years later the Bt cotton area has soared to 15.32 million acres which is 66 per cent of the total estimated cotton area of 23.56 millions acres during the 2007-08 season; grown by 3.8 million small farmers. According to one assessment in India Bt cotton has increased yield by up to 50 per cent, reduced insecticide sprays by half and increased cotton growers income by over Rs10 thousand per acre. Such extensive coverage by the high yielding bollworm-resistant Bt cotton has helped in boosting cotton production to an estimated all time high cotton crop of 31 million bales in 2007-08 up from 28 million bales than last season.
Bt cotton has helped the country in narrowing the gap between national and world average yields. India has achieved high productions mostly by increasing its yield and not increasing its area under cotton. Last year, India exported 4.8 million bales and this season around 5.9 million is expected; so it is rightly to say that India has shifted from traditionally cotton importing to cotton exporting country since the adoption of Bt cotton, crops maximization program and transparent government policy.
The Indian government has approved more than 62 cotton hybrids - four events including double-stacked genes marketed by 25 private seed companies during 2007-08. One event, the GFM developed by Nath Seeds featuring fused genes cry 1Ab and Cry 1Ac is sourced from China. An indigenous event is developed by JK Seeds featuring Cry 1Ac gene is sourced from IIT, Kharagpur. The rest of Bt technology in use in India is owned by Monsanto, licensed to Mahyco and sub licensed to other seed Companies. Experience and high adoption of Bt cotton by farmers have confirmed the efficacy of Bt technology for control of pests and their confidence in the technology.
Although China is one of early adopter countries of Bt cotton (since 1996), in 2007 India overtook China in terms of the area under Bt cotton cultivation and the number of genetically modified cotton seed in the pipeline for approval. India began cultivation of Bt cotton in 2002, but its area under Bt cotton has increased to 9.4 million acres in 2006 exceeding for the first time, that of China's 8.65 million acres. India is the only country to grow all four species of cultivated cotton.
Chinese scientists have developed fifty-five new GM cotton strains, bringing economic returns of 2.5 billion US dollars. China has a cotton area of about 13.2 million acres, the largest producer of cotton in the world - Bt cotton is planted on 9.38 million acres during 2007-08 up from 8.65 million acres last year; which is equivalent to 69 per cent of all cotton planted in China. At present level its cotton production is equivalent to 46.0 million bales. China has a remarkable experience of massive adoption of biotech crops by small farmers who represent some of the poorest people in the world.
It is worth mentioning that Bollgard II technology has a unique and superior double gene technology, Cry 1Ac and Cry2Ab derived from soil-borne bacterium, and provides in-built protection against bollworms and spodoptera caterpillar
In Pakistan, an all time record cotton crop of 14.5 million bales achieved in 2004-05 on the other hand the worst failure of cotton crop was seen in 1983-84 when its production was at 2.78 million bales against year 1982-83 crop of 4.75 million bales - production remained less than 10 million bales during 1993-95, and 1998-1999 due to out break of by cotton leaf curl virus and high temperature more over humid climate condition has contributed to the eruption of different Bollworms like Pink, Spotted and American, which severely damaged the cotton crop in Sindh and Punjab provinces.
Last year Pakistan imported 1.9 million bales at a cost Rs. 27 billion while this year our textile industry has imported the highest 3.5 million bales of cotton worth Rs. 55 billion from the USA, India and Central Asia due to crop shortage in the country. It would be difficult for our textile industry to compete textile giants like China, India, Bangladesh, Vietnam, Indonesia and Sri Lanka in export of textiles when we have to import a larger amount of cotton to meet shortfall of our cotton requirements.
Scientists at National Institute of Biotechnology and Genetic Engineering (NIBGE) Faisalabad, and National Center of Excellence in Molecular Biology (NCEMB) University of the Punjab, Lahore, are in the process of introducing Bt cotton varieties with high tolerance against the cotton leaf curl viruses, the Multan and Burewala strains.
Ministry of Food, Agriculture and Livestock (Minfal) is exploring all possible options to take on Biotech cotton as soon as possible that's why Minfal is negotiating with different international sources from USA, China even India in order to speedup in this regard.
However there are number of obstacles causing delays on Bt cotton adoption:
1. All cottonseeds varieties (Bt and non Bt) are vulnerable to the cotton leaf curl virus furthermore a unique cotton pest mealy bug has emerged in cotton crops.
2. There is no hybrid cottonseed lines at public or private institutes; moreover the existing cottonseed varieties have very low yield
3. Although American technology from Monsanto is considered more reliable and stable than other sources but its license fee, royalty on Bt genes and technology is considered high
4. Political uncertainty in the country
5. Lack of political well
6. Weak IPRs system
7. No biotech policy
8. Large cotton growing area is under exotic and non approved Bt cotton varieties
9. The sale of spurious Bt cotton seeds
10. Needed system for fast implementation and enforcement of Biosafety Guidelines 2005
11. Amended Seed Act 1976 and Plant Breeders rights have to be approved the parliament
12. Cotton seed Control Ordinance need to be activated to check the quality of seeds
13. Poor enforcement system to control illegal & unapproved Bt cotton seeds
The process to take on biotech cotton and other GM crops can get faster if Monsanto can have joint venture with Pakistan's public institutes. It would be a wise approach to speedup the process if the government of Pakistan allows to carry-out biosafety assessment of Bt Cotton by Ministry of Environment, Ministry of Health, and its seed (germplasm) evaluation by Minfal side by side during the same season.
In the last three years illegal genetically engineered cotton is spreading at a brisk pace in Pakistan despite reluctance of some countries to adopt this technology. According to Global Agriculture Information Network report published in January 2008 the illegal Bt cotton varieties planted in about 40 per cent of Pakistan's cotton region. According to 2006-07 estimates, 1 to 1.5 million acres which is 15 per cent of total cotton area were under un approved Bt cotton, whereas, during the current season 2007-08, the area can easily cross 30 per cent mark (2.5 million acres) of the total cotton growing area.
A survey report published in 2008 revealed that Bt transgenic crop was widely grown in cotton growing areas of Sindh and Punjab. The survey report "Status of cotton harboring Bt-gene in Pakistan" was conducted in the cotton growing areas of Sindh and Punjab during July-August 2007. Laboratory investigations were carried out at National Agriculture Research Center for detecting Cry protein. The major objective was to investigate the presence or absence of Cry toxin in Bt transformed cotton. In Sindh province 10 districts Hyderabad, Nawabshah, Sanghar, Mirpur Khas, Dera Allah Yar, Umer Kot, Matiari, Khairpur, Sukkur and Nowshero Feroze were surveyed and samples of cotton were collected from 42 different locations. It was observed that almost 80 per cent of the cotton growing area in Sindh has become under illegal and non-approved Bt cotton. An exotic source of Bt cotton named as Australian Bt was found in the field.
Similarly 11 districts Multan, Khannewal, Lodhran, Bahawalpur, RY Khan, Vehari, Bahawalnagar, Pakpatten, Sahiwal, Jhan and Faisalabad were surveyed in the Punjab and samples of 84 field different sites were collected. Almost 50 per cent area has been occupied by non-approved Bt cotton in these districts. Bt-121 cotton variety has occupied the major area. Beside Aus-Bt cotton genotype other source of Bt cotton local origin was also prevalent in the field.
According to survey in Sindh province, district Sanghar has the maximum area over 90 per cent under illegal Bt cotton. Similarly in Punjab Khanewal, Vehari and Bahawalnagar have the maximum area over 60 per cent under non-approved Bt cotton.
All positive samples harbored Cry1Ac/Ab gene, whereas none of the sample was found to have Cry2Ab and Cry1F genes.
According to the study the level of Bt gene expression varied from low to high indicating that source of seed is different. Threshold level of Bt protein is very important extremely low level of Bt toxin may lead to development of cross-resistance. A wider range of segregation 10-20 per cent was observed in some of the Bt cotton fields. Sever infestation of armyworm and sucking pests was observed in the fields of Bt cotton. All the Bt transformed germplasm is very susceptible to CLCuV. This will play a role in the evolution of new virus strains as it has happened in case of "Burewala virus" resulting in huge losses to cotton crop in the country.
The report highlight that the Bt gene has been transformed into such genetic backgrounds as they do not meet the fiber quality standards in some of the Bt cotton fiber length was shorter when compared with a non transgenic approved cotton variety.
Most of the growers planted Bt cotton first time they only know the word "Bt". Majority of them do not have exact awareness about the resistance mechanism of non-approved Bt cotton against pests. Moreover very wrongly they think Bt cotton has resistance against all kinds of insects and diseases. Probably it has been propagated by seed companies as marketing trick. However most of the farmers were quite clear about the source and name of Bt transformed genotypes. The source of seed was some private seed companies, progressive farmers and researchers.
Bt cotton is being grown with different names i.e. IR-901, IR-2403, IR-2316, Bt-1524, IR-1000, IR-2389, IR-2456, NIBGE 1, ASR-10, ASR-5, ASR-12, ASR-2, ASR-7, Bt-446, Bt-473, Bt-496, CP-140, Bt-121, BR-102, BR-103, Bt-448/10, MG-1, MG-2, MG-3, FH-113, Bt-196, Bt-133, Bt-Karishma, Bt-448-133 and Bt-101. Of all these genotypes Bt-121 occupied more than 40 per cent and was relatively better than other Bt cotton as regard to uniformity.
People involved in this illegal business are making windfall profits without any remorse, and poor farmers are being swindled in the name of Bt. The farmers have no way of knowing whether the seeds they are getting have the Bt gene or are merely spurious seeds.
National Biosafety Guidelines 2005 must be followed to approve all GM crops varieties. This will encourage the introduction of this advanced technology through legal means with complete package of benefits.
Moreover it has been reported that this year the Punjab Seed Corporation (PSC), a semi autonomous government body which provides certified cotton seeds to the farmers, was alleged to have purchased cotton seed of non-approved varieties of Bt cotton from certain well-known farmers. A little while back, the PSC had advertised sale of Bt cotton in national newspapers. Last year PSC had opposed the sale and cultivation of Bt cotton. A ban on the cultivation of non approved Bt cotton is still in place. If the private-sector companies had sold the cotton seed of banned varieties, they would have been tagged "seed mafia" but the government institution's malpractice went unnoticed.
We can reap the benefits of new technology if we take the correct, legal and ethical steps with strict compliance to our own regulatory systems, provided there are immediate and effective measures taken to curb the thriving illegal business and uncontrolled use of technology, provided an appropriate environment is created for public and private sectors to ensure effective incentives for R&D and commercial release of these varieties. However, by allowing the unapproved Bt cotton varieties actually we are not helping our farmers nor doing any service to the country. It will send wrong message to the potential investors in this sector and depriving our public sector institutions who are involved in the development of Bt cotton. It would be in our interest to safe our national trade identity cotton from any butcher hands who want to gamble on our strategic and economical assist.
Seeds of change: Africa seeks to engineer an agricultural revolution
FT Series: The need to feed, Part 2
- Alan Beattie, The Financial Times (UK), June 2 2008
Wanted: a rapid transformation of one of the most complex problems in the world's poorest continent, to take place in the middle of a food crisis.
Thirty years after the first "green revolution" transformed agriculture in Asia and Latin America, as new seed varieties and copious fertiliser enabled farmers to break out of the subsistence trap, Africa is trying to follow suit.
Throughout the 1980s and 1990s, productivity in African farming failed to keep pace with population growth. Any increases reflected bringing more land under cultivation rather than lifting yield. Farmers, agronomists and development experts say that new technology alone, particularly in the short term, will bring no radical transformation. Quicker gains can be made improving markets and transport, which will help expand existing, under-used technologies.
But there is disagreement over whether Africa should seek an agribusiness model based on big commercial farms or concentrate on improving the lot of its millions of smallholders. Moreover, the difficulties in transforming African agriculture are manifold. Some are topological: the continent contains huge varieties of soil and climate, ranging from a Mediterranean climate in the Maghreb to tropical environments to temperate latitudes in South Africa. Crops grown and techniques used in one part often cannot be transferred to others.
So what are the prospects for improvements that will help feed a population approaching 1bn? The cause was given a boost when the Alliance for a Green Revolution in Africa, an association of farmers, agricultural businesses, scientists and research institutions, was founded in 2006 with $150m (£76m, 97m) from the Rocke≠feller Foundation - which also played a central role in funding the first green revolution - and the Gates Foundation.
Namanga Ngongi, president of Agra, says that while Asian farming systems are dominated by similar varieties of wheat and rice, Africa has a wider range of crops including cassava, sorghum, millet and maize. "One size will not fit all," he says.
Mpoko Bokanga, executive director of the African Agricultural Technology Foundation (AATF), a public-private research partnership based in Nairobi, points to big contrasts even within the same country. "In western Kenya in the northern Rift valley there are very fertile areas with high productivity farms whose commercial potential has been well developed," he says. "Then 50km away will be forgotten districts whose farms have a third or a quarter of their yield."
While there are some big river systems, and some areas receive a lot of precipitation, most farming relies on unreliable rainfall: less than 5 per cent of cultivated land is irrigated in Africa, compared with 40 per cent in South Asia.
It will take a while for new technologies to be developed. Africa's agricultural research capability has received almost as little attention as its soils in recent decades, its cash-strapped governments having cut back heavily on basic science. And given the dissimilarity of agronomic conditions on the continent to those elsewhere, it is not easy to piggyback on scientific breakthroughs designed for other markets.
One of the AATF's projects, for example, is to develop a "water-efficient maize" that will tolerate longer periods of drought, a trait that will become increasingly important if, as appears to be the case, climate change is making rains more variable. The foundation will take basic research donated by Monsanto, the US-based agribusiness group. The International Maize and Wheat Improvement Centre in Mexico, a non-profit research institute that played a big role in the first green revolution, will then transplant it into high-yielding maize varieties that will thrive in tropical environments. The varieties will then be distributed to African seed companies without royalties. But Mr Bokanga says that it will be five or six years before strains are available that can be tested in the field.
Further down the road, the green revolution will have to confront one of the most controversial issues in world farming: genetically modified crops. African countries have been slow to adopt GM. South Africa is the only one that has approved a GM variety, though Burkina Faso may be on the point of approving a cotton strain, following its widespread use in India, and Egypt is looking at GM maize.
Some of the aversion to GM in Africa, among governments as well as campaigners, is visceral. In 2002 Zambia refused to accept GM grain as emergency aid in the middle of a food crisis, fearing that it would contaminate local agriculture. The government even rejected offers by the European Union, which has its own deep reservations about GM, to mill the grain before distributing it, to prevent it getting into the farming system.
But Mr Bokanga says that opposition is exaggerated and that farmers are badly informed rather than firmly against. "It is not true that all African governments are opposed to adopting GM," he says. "You have a lot of opponents to biotech who make a lot of noise and capture the local media, and then the outside media thinks that farmers are opposed. Most farmers don't know anything about GM."
[complete article at link above]
RiceTec Signs Licensing Agreement to Field Test Drought Resistant Rice
- RiceTec Inc. and Performance Plants Inc. (press release), June 5, 2008
KINGSTON, ON - RiceTec Inc. and Performance Plants Inc. (PPI) today announce an agreement to develop drought-tolerant rice using Performance Plants' Yield Protection Technology (YPT).
YPT helps protect plants against the damaging effects of drought. A unique feature of this patented technology is that it uses a plant's own genes to enhance its natural response mechanism to drought. YPT makes plants able to tolerate by dry conditions better and recover faster when watered. Extensive field testing by PPI in other crops and ornamental species consistently shows up to 25% seed yield increases under drought conditions.
"The partnership with PPI will allow us to explore, evaluate and hopefully yet further improve the stability of hybrid performance in drought/stressed conditions, giving RiceTec Hybrid Seed another positive attribute that means quality, high-yielding performance while at the same time, minimizing production risk for our customers," said John Nelsen, RiceTec President and CEO.
Under the terms of the agreement, RiceTec will develop YPT rice lines and evaluate their performance under dry land conditions in their proprietary, elite germplasm.
"We are very pleased to be working with RiceTec on this research project," said Peter Matthewman, President, PPI. "It reaffirms the effectiveness of our technology and its ability to help crops flourish under less than ideal growing conditions."
According to Matthewman, the company has previously licensed YPT for application in corn, soybean, turfgrass and ornamentals.
Man-made protocell hosts DNA synthesis
- Simon Hadlington, Chemistry World, June 4, 2008
US researchers have taken a step towards creating a synthetic cell in the laboratory that could resemble the first primitive stirrings of life on Earth. The scientists, from the Howard Hughes Medical Institute in Boston, showed that a mixture of fatty acids and related molecules can spontaneously form stable, hollow vesicles, and that sugars and modified nucleotides can diffuse into this 'protocell'. Once inside, the nucleotides can be induced to polymerise without help from enzymes - a key aspect for prebiotic environments, where complex molecules such as proteins did not exist.
'We are taking a synthetic approach to trying to understand the origins of life, and we are trying to build a protocell model of what we think an early cell might have looked like,' says Jack Szostak, who led the research.
The team systematically investigated a range of fatty acid and related molecules to find a mixture that would self-assemble into permeable vesicles. Phospholipids, which form the basis of 'modern' cell membranes are ruled out because they are highly impermeable and require complex apparatus such as protein pumps and ion channels to allow molecules in and out of the cell.
The researchers showed that a mixture of a fatty acid, its corresponding fatty alcohol, and the glycerol ester of the fatty acid, all combined to spontaneously assemble into vesicles that allowed sugars and modified nucleotides to pass into the vesicle.
To see if the nucleotide could polymerise inside the protocell without the aid of enzymes, the researchers placed a short, simple DNA template 15 bases long within the vesicles. They then added the complementary nucleotide to the medium containing the protocells. 'We saw the monomers diffuse into the cell, bind to the template and spontaneously polymerise,' says Szostak. 'The new chain grew to its full length.'
Szostak says that major questions remain to be answered about how complicated molecules such as nucleotides came into existence and how these then became self-replicating polymers. 'What our model shows is that if something like this did exist on the early Earth, simple cells could take up nutrients from the environment. This represents one of the steps in which we are starting to combine a cell membrane with genetic material to see how they can work together. We are working pretty hard on nucleic acid chemistry and trying to get a more general set of copying reactions.'
Daniel Frankel, who researches protocells at the University of Newcastle in the UK, says that Szostak's latest work is 'very important and very, very exciting. It shows that prebiotically plausible vesicles can take up sugars and nucleotides and this takes the model of the protocell forward significantly.'
*by Andrew Apel, guest editor, andrewapel*at*wildblue.net