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Linking the Global Food Chain and $2.9 Billion in Food Microbiology Testing

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WOODSTOCK, Vt., Aug. 29, 2013 (GLOBE NEWSWIRE) -- via PRWEB - The world's "food chain" is growing increasingly complex, with foodstuffs and finished food products of all types crossing borders at a rapid pace. In the U.S., for example, imported food now represents 15-20% of all the food consumed.

At the same time, food microbiology testing around the world is increasing at an annual growth rate of 5.5%. On the surface, these two trends seem to be in concert--the global food chain is becoming more important and food micro testing is increasing. A closer look, however, reveals inconsistencies.

According to new market research published by Strategic Consulting, Inc. (SCI), microbiology testing for food safety varies extensively around the world. Diagnostic testing by food producers differs by geographic region, by the predominant organisms tested (Salmonella, Listeria, and Campylobacter, for example), and by the type of food product produced (meat, dairy, fruits and vegetables, or processed food). Technical differences in global testing practices also exist, such as the point in the food production chain at which samples are collected, and the test methods used for analysis.

The following data and charts from Food Micro, Eighth Edition: Microbiology Testing in the Global Food Industry (Food Micro--8) are drawn from in-depth interviews with quality and safety managers in food plants around the world. More than 450 food production facilities in 19 countries were surveyed, with more than 140 interviews conducted in Asia--in China, India, Vietnam, Thailand and Indonesia. Many of the Asian surveys were conducted in face-to-face interviews in the native language, in order to provide insights into food testing practices that to date have been difficult to gather.

GEOGRAPHIC DIFFERENCES

In general, microbiology test volumes are increasing globally--up 128% over the past 15 years. Pathogen testing is growing at an even faster rate, and represents an increasing percentage of total food micro testing. Fifteen years ago, pathogen testing represented 13.7% of microbiology testing, while in 2013, it will reach 23.2%.

The general increase in food microbiology testing as well as the more dramatic increase in pathogen-specific testing are not consistent across all the geographies analyzed: North America (NA), Europe (EU), Asia, or other countries of the world (ROW). For example, in North America pathogen testing has grown at greater than 10% for the past few years, while in Europe it has grown at half that rate.

In general, SCI research shows that these four geographic regions have different trends affecting growth in microbiology testing. These trends, combined with public perceptions within each region about food safety, influence testing in the region.

VARIATIONS BY FOOD TYPE

Microbiology testing by food segment (protein, dairy, fruit/vegetable, processed food) also varies around the globe. The protein segment, which includes beef, pork, chicken, fish and eggs, represents 27% of overall microbiology testing in the food industry, but more than 40% of total pathogen testing. The dairy segment, which includes fluid milk, cheese, and other dairy-based products, represents 23% of total testing but just 10% of pathogen testing.

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Linking the Global Food Chain and $2.9 Billion in Food Microbiology Testing

Report proposes microbiology’s grand challenge to help feed the world

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Public release date: 27-Aug-2013 [ | E-mail | Share ]

Contact: Jim Sliwa jsliwa@asmusa.org 202-942-9297 American Society for Microbiology

A greater focus on the role of microbiology in agriculture combined with new technologies can help mitigate potential food shortages associated with world population increases according to a new report from the American Academy of Microbiology.

"Microbes are essential partners in all aspects of plant physiology, but human efforts to improve plant productivity have focused solely on the plant," says Ian Sanders of University of Lausanne, chair of the colloquium that produced the report. "Optimizing the microbial communities that live in, on and around plants, can substantially reduce the need for chemical fertilizers, pesticides and herbicides."

The report, How Microbes can Help Feed the World, is based on the deliberation of a group of scientific experts who gathered for two days in Washington DC in December 2012 to consider a series of questions regarding how plant-microbe interactions could be employed to boost agricultural productivity in an environmentally and economically responsible way.

It starts with a startling statistic: In order to feed the estimated global population of 9 billion in the year 2050, agricultural yields will have to increase by 70-100% .

Improved understanding of plant-microbe interactions has the potential to increase crop productivity by 20% while reducing fertilizer and pesticide requirements by 20%, within 20 years, according to the report. These estimates rest on the recognition that all plants rely on microbial partners to secure nutrients, deter pathogens and resist environmental stress.

The report looks in depth at the intimate relationship between microbes and agriculture including why plants need microbes, what types of microbes they need, how they interact and the scientific challenges posed by the current state of knowledge. It then makes a series of recommendations, including greater investment in research, the taking on of one or more grand challenges such as characterization of the complete microbiome of one important crop plant, and the establishment of a formal process for moving scientific discoveries from the lab to the field.

"New technologies are making plant-microbe ecosystems easier to study and investment in this area of research could have dramatic benefits," says Marilynn Roossinck, Pennsylvania State University, who helped organize the colloquium.

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Report proposes microbiology's grand challenge to help feed the world

Rhodes College student conducts research at St. Jude

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As a participant in the 2013 Undergraduate Research Fellowship Program, Rhodes student Tina Dao, of Memphis, is conducting research at St. Jude.

Memphian and Rhodes College rising junior Tina Dao is participating in the 2013 Undergraduate Research Fellowship (URF) Program presented by the American Society for Microbiology (ASM).

The fellowship program is aimed at highly competitive students who wish to pursue graduate studies in microbiology.

Students conduct full-time research with an ASM member and present research results at the ASM General Meeting the following year.

Dao is conducting research with Michael Johnson, Ph.D. and Jason Rosch, Ph.D. in the Infectious Diseases Department of St. Jude Childrens Research Hospital for a minimum of 10 weeks.

Her research project examines the role of the copper efflux pump and the mechanism of copper-mediated toxicity in Streptococcus pyogenes, which cause strep throat, pneumonia, bacteremia, scarlet fever, pharyngitis, and flesh eating diseases.

A graduate of Wooddale High School in Memphis, Dao is now a biochemistry and molecular biology major at Rhodes.

Additionally, she is a member of the Rhodes Chapter of Gamma Sigma Epsilon Chemistry Honor Society.

Dionne Chalmers is with the Office of Communications at Rhodes College.

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Rhodes College student conducts research at St. Jude

Target 2 forms of iron to control cystic fibrosis lung infection

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Public release date: 20-Aug-2013 [ | E-mail | Share ]

Contact: Jim Sliwa jsliwa@asmusa.org 202-942-9297 American Society for Microbiology

The bacterium Pseudomonas aeruginosa needs iron to establish and maintain a biofilm in the lungs of cystic fibrosis patients, and therapies have been proposed to deprive the bacteria of this necessary element. However, these techniques may not work, according to a new study published in mBio, the online open-access journal of the American Society for Microbiology, because they only target one of the two types of iron that are available in the lung.

Current therapies focus on removing ferric iron [Fe(III)] but leave plenty of ferrous iron [Fe(II)] behind for the bacteria to use, according to the study. The concentration of Fe(II) present in the lungs of patients with cystic fibrosis correlates with disease severity, a sign that pathogens not only use ferrous iron - they thrive on it. These findings could have implications for treatment of P. aeruginosa in patients with cystic fibrosis.

"It is clear that the percentage of the total iron pool that is Fe(II) is substantial, particularly in severely ill patients," write the authors. Despite a wealth of data on the abundance of iron in the airways of patients with cystic fibrosis, this study is the first to make direct measurements of two different bioavailable forms of iron, Fe(III) and Fe(II).

An optimal concentration of bioavailable iron is needed to establish the formation of P. aeruginosa biofilms, thick accumulations of bacteria, polysaccharides, and cellular debris that can build up in the lungs of cystic fibrosis patients. It's also integral to stabilizing biofilms, so therapies have been proposed to perturb P. aeruginosa's uptake and acquisition of iron to fight biofilm development in the lung.

Because Fe(III) is commonly assumed to be the dominant physiologically-relevant form of iron, therapies focus on blocking Fe(III) acquisition. However, Fe(II) may also be present in the lung, reasoned the authors, a fact that could undermine iron-targeting therapies.

They tested sputum samples from a cross-section of 33 cystic fibrosis patients from the US and Belgium. Fe(II) was, indeed, abundant in the lungs of cystic fibrosis patients, and it comprised a considerable amount of the total iron in each sample, confirming the authors' suspicions. What's more, sicker patients had greater quantities of Fe(II), and while Fe(II) concentration was significantly correlated with disease the concentration of Fe(III) was not.

The authors also tested whether inhibiting the uptake of Fe(II) or Fe(III) - or both - would prevent biofilm formation. Using a high-throughput biofilm assay in the lab, they tested the ability of ferrozine, an Fe(II)-specific chelator, and conalbumin, a Fe(III)-specific chelator, to bind iron and prevent the buildup of a biofilm. They found that in a system where both Fe(II) and Fe(III) are present, as they are in the lungs of cystic fibrosis patients, it was most effective to apply both types of chelators: sequestering both forms of iron resulted in a 58% reduction in biofilm accumulation. This suggests that for treating patients, targeting both forms of iron might be more effective than targeting Fe(III) alone.

"Collectively, these studies underscore the importance of a dialectic between laboratory and environmental studies of pathogens such as P. aeruginosa," write the authors. Mechanistic studies of microorganisms in the laboratory can only go so far without real-world information about the chemical conditions under which they live in the human body. The integrated approach used in this study has provided a superior understanding of how iron availability might be manipulated to prevent biofilm formation and can inform the effective design and application of therapeutic strategies for treating P. aeruginosa biofilms.

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Target 2 forms of iron to control cystic fibrosis lung infection

Art of microbiology exhibit to open in Gallery90 at HAYC3

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Monday August 19, 2013

HOOSICK FALLS, N.Y. -- Donna Maria de Creeft, the daughter of the world-renowned Hoosick Falls sculptor Jose de Creeft, will be showing a series of new works on paper, entitled, "Microbiology" in Gallery90 at the Hoosick Falls armory beginninning Aug. 23.

According to De Creeft, much of her work has been influenced by ideas and images gleaned from philosophy, anthropology, psychology, literature, mythology and science, especially chaos theory. However, she also attributes inspiration to her love of Hoosick Falls and the many summers she spent vacationing in the area as a child.

De Creefts exhibit will include a series of "Humanist Prayer Flags" and collages, which, she said, are based loosely on Tibetan prayer flags.

"Theyre like books with pages strung on linen thread," she said. "Each one is like a volume of mixed-media collages that incorporate photographs and illustrations of microscopic detail from scientific texts."

The components de Creeft created for the exhibit, which are drawn, painted, burnt and torn, relate visually to the found images.

The flags are "humanist," she says, "because they are about many of the things that make us human--our cells, our powers of observation, our relationship to the natural world, and our ability to rationally and irrationally make sense of our existence."

De Creefts artwork will be displayed in Gallery 90, located in the basement of the Hoosick Falls armory, between Aug. 23 and Sept. 20.

The opening reception, which is free and open to the public, will take place Friday, Aug. 23 from 6-8 p.m..

A concert by blues guitarist and vocalist Billy Gilbert will accompany the reception.

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Art of microbiology exhibit to open in Gallery90 at HAYC3

UMS researchers produce biofertiliser from oil palm empty fruit bunches

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19th August, 2013

KOTA KINABALU: The Microbiology Research Group at the University Malaysia Sabah (UMS) Biotechnology Research Institute has developed a simple and easy way to produce biofertiliser from oil palm fibre empty fruit bunches (EFB) within 40 days.

Its senior researcher Dr Md Shafiquzzaman Siddiquee and his postgraduate student, Nur Shafawati Saili, had conducted the research on converting oil palm industry waste to the biofertiliser.

The application of biofertiliser in nursery and field trials found among others, successful enhancement of plant growth, root development, an increase in plant branches, inflorescences and yield production.

Huge amounts of waste products are creating lots of environmental problems and ecosystem degradation, while affecting the health of communities, with high disposal costs annually, Md Shafiquzzaman told Bernama, here.

He said composting was an alternative way of transforming the bulky biomass into a valuable, manageable product, for use on plantations or as a market product.

In this respect, the production of palm oil is a key agricultural activity in Malaysia, and the country has become a top producer of the product in the world, while drawing large revenue from it.

Malaysia oil palm plantations account for about 41 per cent of the worlds palm oil production and occupy 4.5 million hectares of land. Oil palm fibres (trunks, fronds and empty fruit bunches) are considered major waste products, he added.

He said using the species specific-strain of Trichoderma in composting has widened, not only as a biological control agent but for accelerating rapid composting, the control of plant diseases, a strong competitive effect on space and nutrients, the ability to degrade woody materials, while increasing the production yield, and as biocontrol, biopesticides, bioherbicides, enzyme and toxin producers.

Md Shafiquzzaman said the specific-strain of Trichoderma used as a biofertiliser had many superior properties to that of the powder-based products presently available in the market.

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UMS researchers produce biofertiliser from oil palm empty fruit bunches

Two Tufts Biomedical Graduate Students Awarded HHMI Research Fellowships

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Newswise BOSTON (August 14, 2013) The Howard Hughes Medical Institute has awarded two doctoral students from the Sackler School of Graduate Biomedical Sciences at Tufts University with 2013 International Student Research Fellowships. Seblewongel Asrat, from Ethiopia, studies the bacterium that causes Legionnaires disease while Jennifer Nwankwo, from Nigeria, studies red blood cell dehydration in sickle cell disease. The HHMI fellowship program provides support for international pre-doctoral students who are conducting outstanding research in the biomedical and related sciences.

Asrat, a molecular microbiology student, seeks to understand how specific cells in the immune system inhibit replication of the bacterium that causes Legionnaires disease, a severe form of pneumonia. She has identified a novel strategy that immune cells use to overcome pathogen attack. Her advisor is Ralph Isberg, Ph.D., Howard Hughes Medical Institute (HHMI) investigator and professor of molecular biology and microbiology at Tufts University School of Medicine (TUSM), and member of both the genetics and molecular microbiology program faculties at the Sackler School of Graduate Biomedical Sciences at Tufts. Asrat is in the MERGE-ID track (Medically-oriented Research in Graduate Education - Infectious Disease) program at the Sackler School. Her co-advisor in this program is Jennifer Chow, M.S., M.D., attending physician in infectious diseases at Tufts Medical Center as well as an assistant professor at TUSM.

Nwankwo studies sickle cell disease, a group of red blood cell disorders that include sickle cell anemia. She specifically studies the role of enzymes that cause red blood cell dehydration and cell adhesion critical events that lead to the painful crises that are the hallmark of sickle cell disease. Her goal is to identify enzymes that could be targeted by new drug treatments for the disorders. Nwankwo is a student in the Pharmacology & Experimental Therapeutics program at the Sackler School, advised by Athar Chishti, Ph.D., professor in the department of integrative physiology and pathobiology at TUSM and member of the cellular & molecular physiology; molecular microbiology; and pharmacology & experimental therapeutics program faculties at the Sackler School.

Asrat and Nwankwo are two of 42 international students selected to become 2013 HHMI International Student Research Fellows. Invited students must be in the third or fourth year of a Ph.D. program at a designated nominating institution.

These highly-competitive fellowships support the training of students who are committed to high-quality research that advances science and human health. This honor reflects the excellence of their work and the dedication of our faculty to provide the best training possible for our students, said Naomi Rosenberg, Ph.D., dean of the Sackler School of Graduate Biomedical Sciences and vice dean for research at Tufts University School of Medicine.

Launched in 2011, the HHMI International Student Research Fellows program has invested almost $10.8 million in these fellowships, now supporting 140 graduate students from 35 countries. Selected students each receive $43,000 for the first year with the opportunity for renewal for two more years. International students, not eligible for most federal and state loans or grants, have very limited options for funding their studies. Through the program, HHMI continues to fulfill its mission of advancing biomedical research and science education by supporting exceptional scientists and students.

The Howard Hughes Medical Institute is a non-profit, medical research organization that ranks as one of the nations largest philanthropies. HHMI was established in 1953 by aviator and industrialist, Howard R. Hughes.

About Tufts University School of Medicine and the Sackler School of Graduate Biomedical Sciences

Tufts University School of Medicine and the Sackler School of Graduate Biomedical Sciences at Tufts University are international leaders in innovative medical education and advanced research. The School of Medicine and the Sackler School are renowned for excellence in education in general medicine, biomedical sciences, special combined degree programs in business, health management, public health, bioengineering and international relations, as well as basic and clinical research at the cellular and molecular level. Ranked among the top in the nation, the School of Medicine is affiliated with six major teaching hospitals and more than 30 health care facilities. Tufts University School of Medicine and the Sackler School undertake research that is consistently rated among the highest in the nation for its effect on the advancement of medical science.

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Two Tufts Biomedical Graduate Students Awarded HHMI Research Fellowships

2 Tufts biomedical graduate students awarded HHMI research fellowships

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Public release date: 14-Aug-2013 [ | E-mail | Share ]

Contact: Siobhan Gallagher 617-636-6586 Tufts University, Health Sciences Campus

BOSTON (August 14, 2013) The Howard Hughes Medical Institute has awarded two doctoral students from the Sackler School of Graduate Biomedical Sciences at Tufts University with 2013 International Student Research Fellowships. Seblewongel Asrat, from Ethiopia, studies the bacterium that causes Legionnaires' disease while Jennifer Nwankwo, from Nigeria, studies red blood cell dehydration in sickle cell disease. The HHMI fellowship program provides support for international pre-doctoral students who are conducting outstanding research in the biomedical and related sciences.

Asrat, a molecular microbiology student, seeks to understand how specific cells in the immune system inhibit replication of the bacterium that causes Legionnaires' disease, a severe form of pneumonia. She has identified a novel strategy that immune cells use to overcome pathogen attack. Her advisor is Ralph Isberg, Ph.D., Howard Hughes Medical Institute (HHMI) investigator and professor of molecular biology and microbiology at Tufts University School of Medicine (TUSM), and member of both the genetics and molecular microbiology program faculties at the Sackler School of Graduate Biomedical Sciences at Tufts. Asrat is in the MERGE-ID track (Medically-oriented Research in Graduate Education - Infectious Disease) program at the Sackler School. Her co-advisor in this program is Jennifer Chow, M.S., M.D., attending physician in infectious diseases at Tufts Medical Center as well as an assistant professor at TUSM.

Nwankwo studies sickle cell disease, a group of red blood cell disorders that include sickle cell anemia. She specifically studies the role of enzymes that cause red blood cell dehydration and cell adhesion critical events that lead to the painful crises that are the hallmark of sickle cell disease. Her goal is to identify enzymes that could be targeted by new drug treatments for the disorders. Nwankwo is a student in the Pharmacology & Experimental Therapeutics program at the Sackler School, advised by Athar Chishti, Ph.D., professor in the department of integrative physiology and pathobiology at TUSM and member of the cellular & molecular physiology; molecular microbiology; and pharmacology & experimental therapeutics program faculties at the Sackler School.

Asrat and Nwankwo are two of 42 international students selected to become 2013 HHMI International Student Research Fellows. Invited students must be in the third or fourth year of a Ph.D. program at a designated nominating institution.

"These highly-competitive fellowships support the training of students who are committed to high-quality research that advances science and human health. This honor reflects the excellence of their work and the dedication of our faculty to provide the best training possible for our students," said Naomi Rosenberg, Ph.D., dean of the Sackler School of Graduate Biomedical Sciences and vice dean for research at Tufts University School of Medicine.

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Launched in 2011, the HHMI International Student Research Fellows program has invested almost $10.8 million in these fellowships, now supporting 140 graduate students from 35 countries. Selected students each receive $43,000 for the first year with the opportunity for renewal for two more years. International students, not eligible for most federal and state loans or grants, have very limited options for funding their studies. Through the program, HHMI continues to fulfill its mission of advancing biomedical research and science education by supporting exceptional scientists and students.

The Howard Hughes Medical Institute is a non-profit, medical research organization that ranks as one of the nation's largest philanthropies. HHMI was established in 1953 by aviator and industrialist, Howard R. Hughes.

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2 Tufts biomedical graduate students awarded HHMI research fellowships

Canine distemper virus: An emerging disease in rare Amur tigers

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Public release date: 13-Aug-2013 [ | E-mail | Share ]

Contact: Jim Sliwa jsliwa@asmusa.org 202-942-9297 American Society for Microbiology

Rare Amur tigers in Russia are succumbing to infection with canine distemper virus (CDV), a pathogen most commonly found in domestic dogs, according to the authors of a study published in mBio, the online open-access journal of the American Society for Microbiology.

Pressure from poaching, decimation of their prey base, and habitat fragmentation have diminished the population of Amur tigers (also called Siberian tigers) to fewer than 500. In the study, a team of scientists from the US and Russia show that CDV infected and caused fatal neurological disease in members of this critically endangered species. They estimate that the virus has killed at least 1% of Amur tigers since 2009.

"Losing 1% of an endangered population is pretty significant," says corresponding author Denise McAloose, Head Pathologist at the Wildlife Conservation Society in The Bronx, New York. "And these losses represent only the deaths we know about. I imagine that there were others that we just never saw," says McAloose.

Since 2001, several rare Amur Tigers have exhibited a set of strange behaviors. Normally a reclusive species, tigers have been seen entering villages and wandering onto roads in the Russian Far East, stumbling, emaciated, and unafraid of humans. (One example can be found on YouTube: https://www.youtube.com/watch?v=mTGRtwV1RII). In each of the documented cases, the tiger eventually died or was destroyed after its condition worsened. Early findings showed that at least one of the tigers was infected with a member of the morbillivirus family of viruses, but conclusive answers had evaded scientists and wildlife managers until now.

Using tissue samples from five wild Amur tigers that died or were destroyed due to neurological disease in 2001, 2004, or 2010, McAloose and her colleagues proved that infection with CDV, a type of morbillivirus, is to blame for the deaths of two of the tigers and caused a serious infection in a third. Under the microscope, the brains of the two tigers that died of CDV infection were riddled with lesions, indicating they suffered from severe viral encephalitis, consistent with their clumsy, abnormal behavior. Molecular analyses to identify CDV-specific proteins and immunolabelling with CDV-specific antibodies confirmed that CDV was present in these tissues. A gene for a CDV-specific gene was detected in the third tiger.

The problem isn't limited to one location, says McAloose. The three tigers that tested positive for CDV were distributed across the Russian Far East.

"That tells us this is a disease that is distributed all across Amur tiger range," McAloose says. "And it also appears to be a relatively new threat to tigers since blood samples from wild tigers prior to 2000 tested negative for antibodies to the virus".

But how do tigers contract a CDV infection? Relatively few domestic dogs in the Russian Far East are vaccinated against CDV, McAloose says, and tigers do kill and eat dogs, so they represent one possible source. But domestic dogs aren't the only suspects.

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Canine distemper virus: An emerging disease in rare Amur tigers

MRSA strain in humans originally came from cattle

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Public release date: 13-Aug-2013 [ | E-mail | Share ]

Contact: Jim Sliwa jsliwa@asmusa.org 202-942-9297 American Society for Microbiology

A strain of bacteria that causes skin and soft tissue infections in humans originally came from cattle, according to a study to be published in mBio, the online open-access journal of the American Society for Microbiology. The researchers who conducted the genetic analysis of strains of Staphylococcus aureus known as CC97 say these strains developed resistance to methicillin after they crossed over into humans around forty years ago. Today, methicillin-resistant S. aureus (MRSA) strain CC97 is an emerging human pathogen in Europe, North and South America, Africa, and Asia. The findings highlight the potential for cows to serve as a reservoir for bacteria with the capacity for pandemic spread in humans.

The researchers sequenced the genomes of 43 different CC97 isolates from humans, cattle, and other animals, and plotted their genetic relationships in a phylogenetic tree. Corresponding author Ross Fitzgerald of the Roslin Institute and the University of Edinburgh in Scotland says strains of CC97 found in cows appear to be the ancestors of CC97 strains from humans.

"Bovine strains seemed to occupy deeper parts of the phylogenetic tree - they were closer to the root than the human strains. This led us to conclude that the strains infecting humans originated in cows and that they had evolved from bovine to human host jumps," says Fitzgerald.

Although the CC97 strains from animals were quite genetically diverse, the human isolates cluster together in two tight, distinct "clades", or relatedness groups, indicating that S. aureus CC97 in cattle crossed over into humans on two separate occasions. Using mutation rates as a molecular clock, the authors determined that the ancestor of clade A jumped from a bovine host to humans between 1894 and 1977 and clade B made the jump between 1938 and 1966.

After they made the jump, the human CC97 strains acquired some new capabilities, says Fitzgerald, thanks to genes encoded on portable pieces of DNA called mobile genetic elements.

"It seems like these elements, such as pathogenicity islands, phages, and plasmids, are important in order for the bacterium to adapt to different host species," says Fitzgerald. "The reverse is true as well: the bovine strains have their own mobile genetic elements."

Perhaps the most problematic new capability the human strains acquired is the ability to resist methicillin, an important antibiotic for fighting staphylococcal infections. Only human strains of CC97 were able to resist the drug, which indicates that the bacteria acquired resistance after they crossed over into humans, presumably through exposure to antibiotics prescribed for treating human infections.

This sequence of events contrasts with the case of a S. aureus strain from pigs, Fitzgerald points out, since a study in 2012 revealed that MRSA ST398 strains evolved the ability to resist methicillin before they crossed over into humans (http://mbio.asm.org/content/3/1/e00305-11). Any number of factors could create these differences, making pigs - but not cattle - a source of a drug-resistant bacterium. At this point, though, there isn't enough information to say whether differences in the S. aureus strains, differences between pigs and cattle, or differences between swine and dairy farming practices might be responsible.

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MRSA strain in humans originally came from cattle


  1. Microbiology