A PERFECT STORM OF ANTIBIOTIC RESISTANCE
Section 12
Antibiotic Resistance in “Biotech” Plants Revised 9-14-2011
Back to Myth # 4
When EPA, FDA and USDA created the policy to use pathogen contaminated sewage sludge on fruits and vegetables in
1981, the Agencies opened the door to infecting fruits and vegetables with human pathogens that were once plant and
soil pathogens. Not only that but, the agencies were allowing antibiotic resistant genes to be directly inserted into
modified chimera plants. Generally studies don't tell everything they find and researchers use different terms. As an
example genetically modified organisms are registered with EPA as new chemical substances and plant researchers
refer to dying trees as decline-affected trees. In the following 1982 study dying trees were found to be infected with
thirteen genera of human type pathogenic bacteria: Pseudomonas (40%); Enterobacter (18%); Bacillus;
Corynebacterium and other gram-positive bacteria (16%); and Serratia (6%). Enterobacter and Serratia are the only
members of the coliform group. None of these bacteria would show up in the sludge/biosolids thermotolerant fecal
coliform test. In 1950, A secret Army experiment exposed the citizens of San Francisco to a soil bacteria once
considered non-pathogenic. For six days in 1950, a mine laying ship in the bay sprayed an aerosol of Serratia
marcescens bacteria into San Francisco. While the bacteria were thought to be harmless, the germs sent 11 people to
hospitals and killed one person, Edward J. Nevin, from a heart infection. In 1977 Senate subcommittee hearings the
Army revealed that it had staged the mock biological attack.(SFC, 2/21/98, p.A15)(WSJ, 10/22/01, p.A1)
In 1982, John M. Gardner, et al., University of Florida at Lake Alfred, reported on “Bacteria in Rough Lemon Roots of
Florida Citrus Trees.” They said, “An aseptic vacuum extraction technique was used to obtain xylem fluid from the roots
of rough lemon (Citrus jambhiri Lush.) rootstock of Florida citrus trees. Bacteria were consistently isolated from vascular
fluid of both healthy and young tree decline-affected [dying] trees. Thirteen genera of bacteria were found, the most
frequently occurring genera being Pseudomonas (40%), Enterobacter (18%), Bacillus, Corynebacterium, and other
gram-positive bacteria (16%), and Serratia (6%). Xylem [vascular] bacterial counts fluctuated seasonally. Bacterial
populations ranged from 0.1 to 22 per mm3 of root tissue (about 102 to 2 x 104 bacteria per g of xylem) when bacterial
counts were made on vascular fluid, but these numbers were 10- to 1,000-fold greater when aseptically homogenized
xylem tissue was examined similarly. Some of the resident bacteria (4%) are potentially phytopathogenic. It is proposed
that xylem bacteria have an important role in the physiology of citrus.”
http://aem.asm.org/cgi/content/abstract/43/6/1335
In 1983, Michael W. Bevan, et al., Plant Breeding Institute, Cambridge and Washington University at St Louis, reported
on “A chimaeric antibiotic resistance gene as a selectable marker for plant cell transformation.” They said, “The T-DNA
region of Agrobacterium tumefaciens tumour-inducing plasmids of the nopaline type1 contains a gene coding for the
enzyme nopaline synthase. This gene is expressed constitutively in host plant cells to which it is transferred during
tumour induction2. We have exploited the regulatory elements of this gene to construct a chimaeric gene that confers
antibiotic resistance on transformed plant cells. The chimaeric gene encodes the expected chimaeric transcripts in plant
cells, and confers on transformed cells the ability to grow in the presence of normally lethal levels of the antibiotic G418
(ref. 3). Experiments using in vitro transformation techniques on single plant cells indicate that this antibiotic resistance
can be used as a selectable marker, and can therefore be used in selecting cells transformed by T-DNA vectors that
have had the genes for hormone autotrophy deleted4. Plant cells transformed by such 'disarmed' T-DNA vectors can be
regenerated into entire plants, whose sexual progeny contain unaltered copies of the inciting T-DNA5. The availability of
this dominant selectable marker should allow a wider range of experiments to be under taken using different host plants.”
http://www.nature.com/nature/journal/v304/n5922/abs/304184a0.html
In 1987, Maria Lucrecia G. Ramos, et al., reported on “Native and inoculated rhizobia isolated from field grown
Phaseolus vulgaris: Effects of liming an acid soil on antibiotic resistance.” They said, “An investigation was made to
determine the tolerance to growth in acid culture medium (pH 4.6), and to several antibiotics, of rhizobia isolated from
Phaseolus vulgaris plants grown in limed and unlimed field plots. The plants were originally inoculated with Rhizobium
strain CO5 and isolates were made after 5 successive crops of beans (only inoculated at the first crop) during a 2 yr
period, and simultaneously from plots planted to beans for the first time. Rhizobium isolates identified as CO5 using
immunodiffusion were all found to be identical to the original CO5 strain in their tolerance to acidity and resistance to 7
antibiotics. However, the isolates of native soil rhizobia from unlimed plots were found to be more tolerant to acid
conditions and less tolerant to chloramphenicol and kanamycin than those isolated from limed plots. The differences in
antibiotic resistance between lime treatments was greater in isolates from plots planted 5 times with beans than in those
taken from plots never planted to this crop. The antibiotic resistant Rhizobium isolates, mainly originating from limed
plots, showed predominantly large, fiat, wet, translucent colonies on yeast mannitol agar (YMA) plates. The antibiotic
sensitive isolates, mainly originating from unlimed plots, showed predominantly small, dry, opaque, circular colonies on
YMA plates. The results confirm that in vitro evaluation of acid tolerance reflects the ability of 'Rhizobium strains to
nodulate legumes growing in acid soil conditions. That significant antibiotic production may occur in the plant-soil system
is considered as an explanation for the observed differences in antibiotic resistance between native rhizobia isolated
from limed and unlimed plots.” http://www.sciencedirect.com/science/article/pii/0038071787900794
In 2001, The Council for Biotechnology Information put out a three page Public Relations Brochure, “The Use of
Antibiotic Resistance Markers to Develop Biotech Crops.” The three page are needed to contradict the few basic
primary facts used by the Biotech industry to justify genetically modified organisms (GMOs): “Scientists use “antibiotic
resistance markers” as a tool for recognizing when they have successfully introduced a new gene into a plant cell. –
Plant biotechnology works by inserting genes that convey advantageous characteristics into plant cells. – One useful
form of marker is a gene that confers resistance to antibiotics. These genes are called “antibiotic resistance markers.”
Scientists generally expose the plant cells to the specific antibiotic to which the antibiotic resistance gene confers
resistance. Because only cells that contain the antibiotic resistance gene can survive, scientists can be sure that some
of those surviving plant cells also contain the advantageous gene. – the antibiotic resistance genes used in plant
biotechnology were obtained from naturally occurring bacteria from human and animal guts or the environment. –
Genes are chosen that occur frequently in natural microbial populations to which people are already exposed. It is
common to find bacterial strains in the human gut and in soil that are resistant to these antibiotics. – These genes are
unlikely to be transferred to bacteria. Even if they were, the genes chosen are already widespread in nature and would
not impact the use of antibiotics in medical or veterinary applications. – The genes chosen confer resistance to a narrow
range of specific antibiotics that are no longer important for medical or veterinary treatment. The most widely used
antibiotic resistance marker, nptII, confers resistance to the antibiotics kanamycin and neomycin.”
http://foodsafety.k-state.edu/articles/12/ant_res_mark_council4biotech.pdf
In 2002, the Union of Concerned Scientists reported on the “Risks of Genetic Engineering.” They said,
“Genetic engineering often uses genes for antibiotic resistance as "selectable markers." Early in the engineering
process, these markers help select cells that have taken up foreign genes. Although they have no further use, the
genes continue to be expressed in plant tissues. Most genetically engineered plant foods carry fully functioning
antibiotic-resistance genes. The presence of antibiotic-resistance genes in foods could have two harmful effects. First,
eating these foods could reduce the effectiveness of antibiotics to fight disease when these antibiotics are taken with
meals. Antibiotic-resistance genes produce enzymes that can degrade antibiotics. If a tomato with an antibiotic-
resistance gene is eaten at the same time as an antibiotic, it could destroy the antibiotic in the stomach. Second, the
resistance genes could be transferred to human or animal pathogens, making them impervious to antibiotics. If transfer
were to occur, it could aggravate the already serious health problem of antibiotic-resistant disease organisms. Although
unmediated transfers of genetic material from plants to bacteria are highly unlikely, any possibility that they may occur
requires careful scrutiny in light of the seriousness of antibiotic resistance. In addition, the widespread presence of
antibiotic-resistance genes in engineered food suggests that as the number of genetically engineered products grows,
the effects of antibiotic resistance should be analyzed cumulatively across the food supply. – One of the most common
applications of genetic engineering is the production of virus-tolerant crops. Such crops are produced by engineering
components of viruses into the plant genomes. For reasons not well understood, plants producing viral components on
their own are resistant to subsequent infection by those viruses. Such plants, however, pose other risks of creating new
or worse viruses through two mechanisms: recombination and transcapsidation. Recombination can occur between the
plant-produced viral genes and closely related genes of incoming viruses. Such recombination may produce viruses
that can infect a wider range of hosts or that may be more virulent than the parent viruses. Transcapsidation involves
the encapsulation of the genetic material of one virus by the plant-produced viral proteins. Such hybrid viruses could
transfer viral genetic material to a new host plant that it could not otherwise infect. Except in rare circumstances, this
would be a one-time-only effect, because the viral genetic material carries no genes for the foreign proteins within which
it was encapsulated and would not be able to produce a second generation of hybrid viruses.”
http://www.ucsusa.org/food_and_agriculture/science_and_impacts/impacts_genetic_engineering/risks-of-genetic-
engineering.html
In 2003, Stephen Johnson Assistant Administrator Office of Prevention, Pesticides, and Toxic Substances U.S.
Environmental Protection Agency, reported on EPA's role in the assessment and regulation of products produced
through biotechnology, before the Committee on Agriculture Subcommittee on Conservation, Credit, and Research U.S.
House of Representatives. Johnson said, “In the early 1980s, companies began to apply the techniques of
bioengineering to agriculture for eventual commercial use. Also at this time, the federal government began to evaluate
its options for regulating products created using biotechnology. In 1986, the federal government released a document
entitled: "Coordinated Framework for Regulation of Biotechnology" which laid out the broad approach to regulating
biotechnology products. – the Agency is committed to ensuring that our regulatory decisions are based on rigorous
scientific information, the highest scientific standards, with a high degree of transparency to ensure our decisions are
available to the public for understanding and oversight. – The Agency believes that regulated biotechnology products
are safe, provided they are used according to the approved labeling. – Science is at the point now where genes can be
moved between unrelated species. In the case of PIPs [plant-incorporated protectants], scientists alter plants to produce
pesticidal substances from any source, for example, from another plant, a bacterium or virus, etc. – EPA has
established procedures for the regulation of microorganisms that are products of biotechnology as "new chemical
substances." – Through the process of biotechnology, scientists can remove the genes that produce the toxic protein
from the bacterium and place them in, for example, a corn plant. The corn plant can now synthesize its own Bt protein
and ward off pests on its own. No external spraying for the target pest is necessary. – Currently, EPA has registered 11
separate PIP products. Ten-of these products are for a Bt protein. The crops have included: potatoes, cotton, field corn,
sweet corn, and popcorn. There have also been Experimental Use Permits issued for Bt tomatoes and Bt soybeans. The
Agency has also established tolerance exemptions for pesticidal proteins from viruses that have been moved to plants
like watermelon, cucumber, potato, and papaya. In 1998, EPA registered a PIP based on the potato leaf roll virus
(PLRV) and a Bt protein. The Bt protein and the PLRV protein were combined to provide virus and insect protection. –
When StarLink corn was registered in 1998, the data concerning the digestibility of the protein was insufficient to make
a complete assessment on the potential for the protein to be a potential food allergen. EPA registered StarLink with
restrictions designed to keep it out of the human food supply such as allowing sales only to animal feed and industrial
processors, and requiring buffer zones between non-StarLink corn). Despite these restrictions, the protein from StarLink
corn was discovered in human food (taco shells). As a result EPA, FDA, and USDA worked closely together to both
divert all corn containing the protein to non-human food uses and to ensure that corn seed for growers would be
StarLink-free. Additionally, an assessment on the potential reports of allergenicity in people was conducted in
cooperation with the Centers for Disease Control and Prevention (CDC). No incidents of allergenicity have been
confirmed from the CDC investigations. The registration for StarLink corn has been cancelled. EPA meets regularly with
FDA and USDA to monitor the success of the containment program for StarLink, and determine if any changes are
necessary in the testing program for corn being used in dry milling. In order to assure that the StarLink situation does
not occur again, EPA has instituted a policy of not approving registrations that are restricted to animal and industrial
uses in crops people use for food.” http://www.usembassy.it/viewer/article.asp?article=/file2003_06/alia/A3061804.htm
StarLink corn was just the tip of the iceberg for contamination of food crops meant for human consumption. EPA has
restricted crops grown on Class B sludge to feed crops for animals. However, my investigation in Kansas City revealed
that many grain purchasing and storage facilities do not have the capacity to separate grain for animal consumption
from those grains intended for human consumption. Not only that but grain for animal consumption brings the farmer
less money. Therefore, a don't ask, don't tell policy has developed between the receiving grain facilities and farmers. In
the Kansas City case, the contract farmers were not aware the grain was intended for animal feed only, or if they were,
they would not admit it due to the higher price they were being paid for pathogen contaminated grain. While that may
seem like a strong statement without merit, I was unknowingly selling grain to the same grain facility grown on soil that
was contaminated with over 800,000 colonies each of Salmonella and E. coli per 100 grams of soil. That contamination
was just from the runoff from the adjacent sludge farm. While there was no test for antibiotic resistant bacteria, transfer
of antibiotic resistant DNA among soil bacteria is common.
In the Fall 2005 UMass Extension Landscape, Nursery & Urban Forestry Program, fact sheet, “Wetwood and slime flux”
we find that a human pathogen also kills trees. Daniel H. Gillman, Plant Pathologist said, “The bacteria Enterobacter
cloacae along with several other bacteria commonly occur in elms in association with the water-soaked condition of
wood called bacterial wetwood. – Wetwood and the bacteria consistently associated with it occur in nearly all elm
(Ulmus) and poplar (Populus). In addition, fir (Abies), hemlock (Tsuga), maple (Acer), mulberry (Morus), oak (Quercus),
and white pine (Pinus strobus) often have bacterial wetwood. – Wetwood occupies the trunk, branches, and roots of
affected trees. Most bacteria associated with wetwood commonly inhabit soil and water.” http://www.umassgreeninfo.
org/fact_sheets/diseases/wetwood_slime_flux.pdf
Some researchers think antibiotic resistant DNA in plants should be ignored, not because the DNA can not be
transferred between bacteria, but because there are so many antibiotic resistant soil bacteria. The point that is not
considered is that pathogenic human bacteria can transfer human virulence DNA to soil bacteria that would not normally
infect humans or animals. As an example, in 2008, Sandrine Demanèche, et al., Université de Lyon, reported on
“Antibiotic-resistant soil bacteria in transgenic plant fields.” They said, “In this study, we combined culture-dependent
and -independent approaches to study the prevalence and diversity of bla genes in soil bacteria and the potential
impact that a 10-successive-year culture of the transgenic Bt176 corn, which has a blaTEM marker gene, could have
had on the soil bacterial community. – Our results indicate that soil bacteria are naturally resistant to a broad spectrum
of beta-lactam antibiotics, including the third cephalosporin generation, which has a slightly stronger discriminating
effect on soil isolates than other cephalosporins. – After many years of contradictory data about the actual production of
antibiotics by indigenous microorganisms in soil (6), several reports were published confirming that antibiotics are
produced in soils at sufficiently high concentrations to inhibit bacterial growth in the vicinity of the producers (7–10). –
We addressed the questions of antibiotic resistance gene evolution and GMPs impact by investigating the diversity of
bla genes in soil bacteria from fields cultured for as many as 10 successive years with transgenic (Bt176 event) and
traditional corn lines and from a prairie soil in the same area. – In the corn fields, the prevalence of cultivable ampicillin-
resistant bacteria exhibited some heterogeneity that correlated not to the transgenic status of the plant but rather to
field location. Percentages of resistant bacteria varied from 0.4% to 6.5% of total cultivable bacteria between samples
T2 and T1, respectively, and from 5.5% to 8.0% in samples C2 and C1, respectively (SI Table 1). – In prairie soil,
prevalence of ampicillin-resistant bacteria is significantly higher, ranging from 54.4% to 69.6% in P2 and P1 samples,
respectively (SI Table 1). – Our data are sufficiently informative to conclude that the risk that antibiotic-resistant genes
in GMPs can pose to commensal and clinical bacteria should be considered as almost null. This risk has to be neglected
not because these genes cannot be transferred but because the plethora of genes already present in soil bacteria and
the constant evolution to which they are subjected limit the impact that a newly acquired, yet identical, gene from a plant
can have.”
http://www.pnas.org/content/105/10/3957.full
In 2011, Kathryn Patterson Sutherland, et al., Rollins College, Winter Park, Florida, reported on a “Human Pathogen
Shown to Cause Disease in the Threatened Eklhorn Coral Acropora palmata.” They said, Coral reefs are in severe
decline. Infections by the human pathogen Serratia marcescens have contributed to precipitous losses in the common
Caribbean elkhorn coral, Acropora palmata, culminating in its listing under the United States Endangered Species Act.
During a 2003 outbreak of this coral disease, called acroporid serratiosis (APS), a unique strain of the pathogen,
Serratia marcescens strain PDR60, was identified from diseased A. palmata, human wastewater, the non-host coral
Siderastrea siderea and the corallivorous snail Coralliophila abbreviata. In order to examine humans as a source and
other marine invertebrates as vectors and/or reservoirs of the APS pathogen, challenge experiments were conducted
with A. palmata maintained in closed aquaria to determine infectivity of strain PDR60 from reef and wastewater sources.
Strain PDR60 from wastewater and diseased A. palmata caused disease signs in elkhorn coral in as little as four and
five days, respectively, demonstrating that wastewater is a definitive source of APS and identifying human strain PDR60
as a coral pathogen through fulfillment of Koch's postulates. A. palmata inoculated with strain PDR60 from C. abbreviata
showed limited virulence, with one of three inoculated fragments developing APS signs within 13 days. Strain PDR60
from non-host coral S. siderea showed a delayed pathogenic effect, with disease signs developing within an average of
20 days. These results suggest that C. abbreviata and non-host corals may function as reservoirs or vectors of the APS
pathogen. Our results provide the first example of a marine “reverse zoonosis” involving the transmission of a human
pathogen (S. marcescens) to a marine invertebrate (A. palmata). These findings underscore the interaction between
public health practices and environmental health indices such as coral reef survival.” http://www.plosone.org/article/info%
3Adoi%2F10.1371%2Fjournal.pone.0023468
When we look at the big picture, the experts have a hard time understanding that animals and fowls are the first to be
exposed to antibiotic resistant organism and DNA particle contaminated water and plants. It is almost as though these
experts don't live in the same world we do.
Next Antibiotic Resistance in Animals and Birds
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