February 2020
It looks like the next generation of GM wonder-plants is under development in Scotland.
About 5% of world crops, some $50 billion worth, are lost due to bacterial disease each year. One of the most common such infections is Pseudomonas syringae which attacks a wide variety of important crops, including tomato, kiwi, peppers, olive, soyabeans and fruit trees. Once the bacteria have gained a foothold in one part of a uniform commercial crop, they spread rapidly through the whole.
Breeding crops for resistance to bacterial disease has had only limited success. Chemical crop protectants are increasingly unpopular with consumers. Treating crops with conventional antibiotics is frowned upon as it fuels antibiotic resistance in human pathogens and compromises our ability to treat diseases.
Genetic engineers have hit on the idea of creating crops which generate 'bacteriocins'.
Showing posts with label bacteria. Show all posts
Showing posts with label bacteria. Show all posts
Glyphosate attack by stealth
February 2020
As pointed out before, there's a huge scope for current GM foods to impact on the microbes inside our gut and, along with that, our health [1].
Besides the novel nature of the foods themselves, there's the glyphosate-based herbicides sprayed on and accumulated by most commercial GM crops. Glyphosate blocks a vital biochemical pathway in green plants, but the pathway is also present in many bacteria. This suggests a very real possibility that the herbicide in GM foods could be devastating our health by stealth.
What is the science telling us about this?
As pointed out before, there's a huge scope for current GM foods to impact on the microbes inside our gut and, along with that, our health [1].
Besides the novel nature of the foods themselves, there's the glyphosate-based herbicides sprayed on and accumulated by most commercial GM crops. Glyphosate blocks a vital biochemical pathway in green plants, but the pathway is also present in many bacteria. This suggests a very real possibility that the herbicide in GM foods could be devastating our health by stealth.
What is the science telling us about this?
Hornless gene edited cattle with extras
November 2019
Funny, how history keeps repeating itself. In the early 1990s, the slow-to-rot FlavrSavr GM tomato was going to be the poster child for genetic transformation. Its creators in Calgene, were convinced they knew exactly what DNA sequences they had inserted and touted the precision of the technology in their representations to the US Food and Drug Federation (FDA). Interestingly, the FDA asked Calgene to prove the claim.
The upshot was that Calgene discovered bits of DNA from the bacterial vector (Agrobacterium) had also been inserted into the GM tomato genome.
Quarter of a century later, genetic transformation is old-hat and gene-editing is all the rage because it's precise. So much so, that the edits deliver the same outcome as "could be achieved by breeding in the farmyard".
Super-simplified agri-systems support disease
August 2019
In 1996, an outbreak of E.coli 0157 bacterial disease in Scotland involved the largest recorded number of infected adults in whom the early digestive-tract symptoms progressed to life-threatening kidney disease. Twenty-eight of them died.
That same year, 7,966 individuals were diagnosed with E.coli 0157 infection in a single outbreak in Japan.
Because the guts of healthy cattle are a reservoir for E.coli 0157, the animals, their manure, and the land they've grazed, are potential sources of the infection. The bacteria can also make their way from fields into the water supply.
The Scottish E.coli 0157 outbreak was caused by contaminated raw meat stored next to cooked meat. The Japanese outbreak was caused by radish sprouts contaminated by infected water.
E.coli 0157 -
In 1996, an outbreak of E.coli 0157 bacterial disease in Scotland involved the largest recorded number of infected adults in whom the early digestive-tract symptoms progressed to life-threatening kidney disease. Twenty-eight of them died.
That same year, 7,966 individuals were diagnosed with E.coli 0157 infection in a single outbreak in Japan.
Because the guts of healthy cattle are a reservoir for E.coli 0157, the animals, their manure, and the land they've grazed, are potential sources of the infection. The bacteria can also make their way from fields into the water supply.
The Scottish E.coli 0157 outbreak was caused by contaminated raw meat stored next to cooked meat. The Japanese outbreak was caused by radish sprouts contaminated by infected water.
Organic foods have always been seen as
an arch-enemy by biotech proponents. In a desperate attempt to trash
organics, they've even been blamed for deadly infections of E.coli
0157 bacteria.
Medicine's climate change
February 2019
"Antibiotic resistance in our pathogens is medicine's climate change: caused by human activity, and resulting in more extreme outcomes".(Kurenbach).These 'extreme outcomes' include conservative estimates that tens of thousands of Americans die each year due to previously-treatable, but now antibiotic resistant, infections. Warnings of this threat go back half a century.
Take horizontal gene transfer seriously - now
February 2019
The risk to health from artificial antibiotic resistance genes being used as markers during the creation of most GMOs was recognised in Europe back in the 1990s. However, lulled by mathematical modelling suggesting horizontal gene transfer (HGT) would never be significant in a complex, natural environment, the problem wasn't taken too seriously [1].
The risk to health from artificial antibiotic resistance genes being used as markers during the creation of most GMOs was recognised in Europe back in the 1990s. However, lulled by mathematical modelling suggesting horizontal gene transfer (HGT) would never be significant in a complex, natural environment, the problem wasn't taken too seriously [1].
Herbicides stimulate antibiotic resistance
February 2018
Multi-antibiotic resistance in pathogenic microbes is a serious, and increasingly common, occurrence. It complicates the treatment of infectious diseases, makes health care more expensive, and can be a death-sentence for the patient.
We know that, once a pathogen evolves a mutant gene for antibiotic resistance, this can be passed to other microbes by horizontal gene transfer. Long ago, concerns were raised that the artificial antibiotic resistance genes often added to GM crop plants as markers during their development could fuel the emergence of antibiotic resistant pathogens. No one seems to be tracking whether this is a reality, but bugs can make themselves resistant to toxic medicines by other means, and counter-intuitively these 'other means' can be fuelled by herbicide-tolerant GM crops.
When bacteria are exposed to a toxin, their first line of defence is to switch on their own pumps to rid themselves of it. If this physiological mechanism can kick in fast enough (before the toxin kills it), the bug can make itself resistant to an antibiotic for as long as necessary.
The link to GM crops is that herbicidal chemicals and their spray co-formulants are also toxic to bacteria. Tests on the glyphosate-based herbicide used on most current GM crops, and on dicamba and 2,4-D which are up-and-coming replacements for glyphosate, plus the 'surfactants' added to all three to aid penetration into the weeds, showed they all trigger the toxin-pump mechanism in three commonly pathogenic bacteria. 'Surfactants' are detergents, classed as 'inerts' by US Environmental Protection Agency (EPA), and are ignored in safety assessments. However, the bacteria clearly don't find them 'inert'.
Multi-antibiotic resistance in pathogenic microbes is a serious, and increasingly common, occurrence. It complicates the treatment of infectious diseases, makes health care more expensive, and can be a death-sentence for the patient.
We know that, once a pathogen evolves a mutant gene for antibiotic resistance, this can be passed to other microbes by horizontal gene transfer. Long ago, concerns were raised that the artificial antibiotic resistance genes often added to GM crop plants as markers during their development could fuel the emergence of antibiotic resistant pathogens. No one seems to be tracking whether this is a reality, but bugs can make themselves resistant to toxic medicines by other means, and counter-intuitively these 'other means' can be fuelled by herbicide-tolerant GM crops.
When bacteria are exposed to a toxin, their first line of defence is to switch on their own pumps to rid themselves of it. If this physiological mechanism can kick in fast enough (before the toxin kills it), the bug can make itself resistant to an antibiotic for as long as necessary.
The link to GM crops is that herbicidal chemicals and their spray co-formulants are also toxic to bacteria. Tests on the glyphosate-based herbicide used on most current GM crops, and on dicamba and 2,4-D which are up-and-coming replacements for glyphosate, plus the 'surfactants' added to all three to aid penetration into the weeds, showed they all trigger the toxin-pump mechanism in three commonly pathogenic bacteria. 'Surfactants' are detergents, classed as 'inerts' by US Environmental Protection Agency (EPA), and are ignored in safety assessments. However, the bacteria clearly don't find them 'inert'.
GM plants grow polio vaccines
October 2017
World-wide, polio is now a disease of the past in all but two countries. The battle has been waged with mass vaccination programmes reaching, for example, 95% of infants in Europe. Even in Pakistan and Afghanistan, polio's last stand, the annual incidence has been reducing dramatically year-on-year and is down to a few tens of cases. Indeed, conquering this virus has been one of the great success stories of modern medicine.
World-wide, polio is now a disease of the past in all but two countries. The battle has been waged with mass vaccination programmes reaching, for example, 95% of infants in Europe. Even in Pakistan and Afghanistan, polio's last stand, the annual incidence has been reducing dramatically year-on-year and is down to a few tens of cases. Indeed, conquering this virus has been one of the great success stories of modern medicine.
It's the bugs not the Bt
October 2017
Several varieties of 'Bt' insecticide are now widely generated by commercial GM crops.
These bacterial proteins are rarely directly toxic, but react with the gut lining of the target pest, creating a lesion in the gut wall. Death of the insect after 2 to 4 days, is a result of gut microbes leaking into the body.
Indeed, experiments have indicated that, for the majority of moth pest species, if their gut microbes have been destroyed by pre-treatment with antibiotics, Bt toxins are no longer able to kill them.
Putting this another way, death-by-Bt happens when the normally beneficial bugs in the healthy pests' gut move into the body where they become pathogenic.
Several varieties of 'Bt' insecticide are now widely generated by commercial GM crops.
These bacterial proteins are rarely directly toxic, but react with the gut lining of the target pest, creating a lesion in the gut wall. Death of the insect after 2 to 4 days, is a result of gut microbes leaking into the body.
Indeed, experiments have indicated that, for the majority of moth pest species, if their gut microbes have been destroyed by pre-treatment with antibiotics, Bt toxins are no longer able to kill them.
Putting this another way, death-by-Bt happens when the normally beneficial bugs in the healthy pests' gut move into the body where they become pathogenic.
GMM contamination
September 2017
Many food and feed additives, produced once upon a time by chemical synthesis or extraction from natural sources, are now derived from fermentation of GM micro-organisms (GMMs).
EU rules require that such additives in the final product must be pure. This means that the GMM itself (alive or dead) or any artificial DNA inserted into it must have been removed.
Accordingly, no special labelling is required for GMM-derived additives. Also, there is no regulatory control system in place for the products of GMMs. It is assumed the company marketing the additive will verify the absence of the GMM and its novel DNA in the final substance.
Besides use as food processing aids and as a means of conferring artificial qualities on food products, GMM-derived additives include 'health' promoting substances, such as vitamins.
In 2014, EU regulators were notified that a German official enforcement laboratory had detected live GM bacteria in a consignment of 'riboflavin' feed additive from China.
Many food and feed additives, produced once upon a time by chemical synthesis or extraction from natural sources, are now derived from fermentation of GM micro-organisms (GMMs).
EU rules require that such additives in the final product must be pure. This means that the GMM itself (alive or dead) or any artificial DNA inserted into it must have been removed.
Accordingly, no special labelling is required for GMM-derived additives. Also, there is no regulatory control system in place for the products of GMMs. It is assumed the company marketing the additive will verify the absence of the GMM and its novel DNA in the final substance.
Besides use as food processing aids and as a means of conferring artificial qualities on food products, GMM-derived additives include 'health' promoting substances, such as vitamins.
In 2014, EU regulators were notified that a German official enforcement laboratory had detected live GM bacteria in a consignment of 'riboflavin' feed additive from China.
Bt insecticide risks in the agricultural landscape
April 2017
As the biotech industry and regulators cling to the notion that 'Bt' insecticide is toxic only to the target pests and is easily digested by mammals just like any other protein, science is throwing a few flies in their ointment.
GM crop plants have been created which generate one or several artificial versions of 'Bt' insecticides. These proteins, in their natural forms, are produced by soil bacteria, Bacillus thuringiensis.
It's disturbing to read in a recent scientific paper that:
As the biotech industry and regulators cling to the notion that 'Bt' insecticide is toxic only to the target pests and is easily digested by mammals just like any other protein, science is throwing a few flies in their ointment.
GM crop plants have been created which generate one or several artificial versions of 'Bt' insecticides. These proteins, in their natural forms, are produced by soil bacteria, Bacillus thuringiensis.
It's disturbing to read in a recent scientific paper that:
"Bt toxins can be transferred via the food web and accumulate in organisms to different degrees".
New GM insecticide
December 2016
Scientists at biotech company, DuPont Pioneer, have been busy searching around in the soils of America for an alternative to 'Bt' insecticides. These pest-killing proteins, whose ancestors came from Bacillus thuringiensis soil bacteria, have proved a marvellous money-spinner for two decades. Now, pest resistance to Bt toxins is rising, and even the new generations of GM crops with stacked Bt variants look like having a limited shelf-life.
DuPont has its fingers crossed that it's found a solution. Its scientists have found a previously uncharacterised protein, designated 'IPD072Aa', which just might serve its purpose.
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| Photo: Creative Commons |
DuPont has its fingers crossed that it's found a solution. Its scientists have found a previously uncharacterised protein, designated 'IPD072Aa', which just might serve its purpose.
D.I.Y. bugs
October 2016
Ever since CRISPR [1] hopped onto the
biotech platform, replacing bits of the living world to suit your
individual tastes or whims has suddenly become possible [2]. And you
don't have to be a scientist to do it.
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| Photo Creative Commons |
CRISPR/Cas9 gene editing
March 2016
GM is changing. Forget shooting the genome to bits with a
micro-blunderbuss in the hope that the novel DNA-bullets lodge somewhere
useful. Now genetic engineers have a
simple, inexpensive and remarkably effective method for making specific DNA
modifications.
The latest from biotech is 'CRISPR/Cas9', a technique which needs little training and
nothing too fancy or expensive in the way of laboratory equipment, and is
rapidly eclipsing all other GM methods.
The culture of neatly simple science
A book has just been published which describes the whole, sorry, history of "How the Venture to Genetic Engineer Our Food Has Subverted Science, Corrupted Government, and Systematically Deceived the Public".
Lawyer, Steve Druker, has cast a critical, analytical eye over the handling of GM by regulators, corporations, the media, prestigious institutions, and respected scientists, and has produced a very disturbing account.
In the conclusion of his investigation he asks the question who was ultimately responsible for the delinquencies and associated problems of the whole GM enterprise. His surprising answer is scientists.
Back in the 1970s, the public were already voicing concerns about the safety of GMOs. Anticipating that their research would become tied up in red tape, scientists convened three conferences ostensibly to evaluate the safety of GM. These meetings have since been used as proof of how responsible scientists are, and as a reassurance that scientists can safely be left to regulate themselves.
However, transcripts and interviews with participants of these meetings reveal a careful control over who attended them, how issues were discussed, and what information was disseminated. The focus was on how to persuade the "guys out there" that "there is nothing to worry about". Safety issues "tended to be factored out of consideration rather than confronted".
Suicide-bomber organisms
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| Image Creative Commons |
In 2000, 193 governments signed up to a moratorium created at the UN Convention on Biological Diversity which specified that Genetic Use Restriction Technologies (GURTS) would not be field tested nor commercialised.
GURTS, also known as 'terminator technologies', span any genetic trick used to prevent reproduction of GMOs.
The first GURTS were used to produce GM plants with sterile seed which farmers couldn't 'steal' to grow the next year's crop, and which provided very cost-effective in-built protection for industry patent rights. Concerns were raised, and never resolved, that the artificial fertility-damaging genes could spread into conventional crops and cripple yields.
Things went quiet for a while, but then terminator trees loomed over the horizon and, this year, the Brazilian government began to wrestle with idea of embracing crops with GURTS.
It's also emerging that some very fancy genetic systems for self-destruction are under development.
Genetic firewalls
June 2015
Proteins are made up from chains of standard building blocks termed 'amino-acids'. Amino acids can react with each other to form a chain, and have a side-arm which can be any one of some 24 specific molecules each having its own particular properties. The important properties of the amino-acid side-arms include, for example, size, shape, reactivity, bonding capacity and electrical charges. It's the specific sequence of amino-acid side-chains which dictate the properties of the protein they make up, for example, how it folds into a 3-dimensional shape, what chemicals or chemical groups it can react with or bind to, how easily it can be digested, and its toxicity.
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| Photo Creative Commons |
Chemical engineers can create an almost infinite variety of artificial amino-acids by attaching novel side-arms. Unnatural amino-acids aren't any use to natural living organisms, but biotech scientists have hit on them as a basis for terminator technology for their genetically modified organisms (GMOs). The principle is that an essential enzyme (see below) is cleverly redesigned to incorporate a novel amino-acid while still preserving its enzymic function.
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