Tag Archives: MRSA

Bacteria in ancient Druid “healing soil” found to stop the growth of super bugs

Researchers analyzing Northern Ireland soil report finding a previously unknown strain of bacteria that is effective against four of the top six drug-resistant superbugs, including MRSA.

A landscape from Boho, County Fermanagh, Northern Ireland. Image credits: Youngbohemian / Wiki Commons.

Folk remedies are rarely as useful as they’re touted — but in some rare instances, they can be surprisingly effective. This turned out to be the case with the soil found in the area of Boho, County Fermanagh, close to the border between Ireland and Northern Ireland.

The area has been inhabited since at least 4,000 years ago, and most notably, it was also inhabited in medieval times. Around the year 500, it was also inhabited by Druids — high-ranking healers and administrative figures of Celtic populations. There are mentions of the Druids (and some subsequent populations) using local soils to treat many ailments including toothaches, throat and neck infections.

Geologically, the area is very diverse, with habitats ranging from limestone karst to acidic bogs. As a result, the soils also exhibit a rare variability with an interesting chemistry. In this new study, researchers focused especially on an area of alkaline grassland called the Boho Highlands, which was touted as having healing properties.

Dr. Gerry Quinn, member of the research team and a previous resident of Boho, was aware of the legends surrounding the soil, so together with colleagues from Wales, Brazil, Iraq and Northern Ireland, he set out to analyze it and see whether there is some truth to these stories.

Within the soil, they discovered a new species of bacteria, which they call Streptomyces sp. myrophorea, so named because it produces a distinctive fragrance similar to that of oil of wintergreen (myrrh). This bacterium inhibited the growth of four of the top six multi-resistant pathogens, which the World Health Organization has highlighted as being responsible for healthcare-associated infections:

  • Vancomycin resistant Enterococcus faecium (VRE);
  • methicillin-resistant Staphylococcus aureus (MRSA);
  • Klebsiella pneumonia;
  • and Carbenepenem-resistant Acinetobacter baumanii.

Zone of inhibition produced by Streptomyces sp myrophorea on a lawn of MRSA. The bacteria is the brown spot, and the lighter color around the spot shows that it is inhibiting the spread of the MRSA which is surrounding it. Credit: G Quinn, Swansea University.

In other words, the bacterium is effective against 4 of the 6 most dangerous drug-resistant pathogens. To make it even more appealing, it also seems to halt both gram positive and gram negative bacteria, which differ in the structure of their cell wall, suggesting it could be a part of robust, broad-spectrum treatments.

However, the effect of this bacteria on the human body is not fully known. It’s also not exactly clear how the bacterium is fighting these drug-resistant pathogens — both matters are currently being investigated by the team.

The genome of the bacterium has also been sequenced. As more and more pathogens are developing drug resistance, finding new antibiotics to deal with them is crucial. Quinn and colleagues suggest that there are chances key elements might lie in some folk remedies, a field called ethnopharmacology. This isn’t to say that we should all trust folk remedies at the expense of established medicine — this is saying that within some natural environments, there may be compounds which could be harvested and used to deal with severe infections or to prevent the spread of pathogens. Professor Paul Dyson of Swansea University Medical School comments:

“This new strain of bacteria is effective against 4 of the top 6 pathogens that are resistant to antibiotics, including MRSA. Our discovery is an important step forward in the fight against antibiotic resistance.”

“Our results show that folklore and traditional medicines are worth investigating in the search for new antibiotics. Scientists, historians and archaeologists can all have something to contribute to this task. It seems that part of the answer to this very modern problem might lie in the wisdom of the past.”

Gerry Quinn also adds:

“The discovery of antimicrobial substances from Streptomyces sp.myrophorea will help in our search for new drugs to treat multi-resistant bacteria, the cause of many dangerous and lethal infections.”

“We will now concentrate on the purification and identification of these antibiotics. We have also discovered additional antibacterial organisms from the same soil cure which may cover a broader spectrum of multi-resistant pathogens.”

Journal Reference: Luciana Terra et al. A Novel Alkaliphilic Streptomyces Inhibits ESKAPE Pathogens, Frontiers in Microbiology (2018). DOI: 10.3389/fmicb.2018.02458.

New bacteria strain.

Irish dirt might cure the world of (most) multi-drug-resistant bacteria

Irish soil might win us the fight against drug-resistant superbugs. Literally!

New bacteria strain.

Growth of the newly discovered Streptomyces sp. myrophorea. Although superficially resembling fungi, Streptomyces are true bacteria and are the source of two-thirds of the various frontline antibiotics used in medicine.
Image credits G Quinn / Swansea University

An international team of researchers based at the Swansea University Medical School, UK, reports finding a new strain of bacteria that can murder pathogens that our antibiotics increasingly cannot. The bacteria has been found in soil samples recovered from an area of Fermanagh, Northern Ireland.

Bad bugs get grounded

“This new strain of bacteria is effective against 4 of the top 6 pathogens that are resistant to antibiotics, including MRSA. Our discovery is an important step forward in the fight against antibiotic resistance,” says Professor Paul Dyson of Swansea University Medical School, paper co-author.

The finding is far from inconsequential. The World Health Organisation (WHO) describes rising antibiotic resistance as “one of the biggest threats to global health, food security, and development today”. Further research also estimated that antibiotic-resistant ‘superbugs’ could lead up to 1.3 million deaths in Europe alone by 2050.

The team named their discovery Streptomyces sp. myrophorea. It was discovered in the Boho Highlands, County Fermanagh, Northern Ireland, hiding in the soil. The researchers investigated the soils there as Dr. Gerry Quinn, a previous resident of the area, became curious to investigate local healing traditions.

Those traditions called for a small amount of soil to be wrapped up in cotton cloth and applied to cure ailments varying from toothaches to throat or neck infections. The team notes that the area has been inhabited for at least 4,000 years — first by Neolithic tribes and later druidic tribes — who may have started this tradition.

Lab tests later revealed the presence of the strain in local soils, and clued the team in on their impressive antibacterial properties. This bacteria inhibited the growth of four of the top six multi-resistant pathogens (those listed by the WHO as being responsible for healthcare-associated infections): Vancomycin-resistant Enterococcus faecium (VRE), methicillin-resistant Staphylococcus aureus (MRSA), Klebsiella pneumonia, and Carbenepenem-resistant Acinetobacter baumanii. It was also successful in inhibiting both gram positive and gram negative bacteria, which differ in the structure of their cell wall. Gram-negative bacteria are, generally speaking, more resistant to antibiotics.

It is not yet clear exactly how the bacteria do this, but the team is hard at work finding out.

New bacteria strain.

Zone of inhibition (light brown) produced by Streptomyces sp myrophorea (brown spot) on a lawn of MRSA.
Image credits G Quinn / Swansea University.

The active compounds secreted by Streptomyces sp.myrophorea could help create a new class of treatment against multi-drug resistant bacteria, the study reports. These pathogens are one of the most pressing threats to public health currently, as doctors are often left powerless to treat them. They’re especially dangerous in hospitals, where the large density of patients (often with weakened or compromised immune systems) means easy pickings for such pathogens.

“Our results show that folklore and traditional medicines are worth investigating in the search for new antibiotics,” Professor Dyson says. “Scientists, historians, and archaeologists can all have something to contribute to this task. It seems that part of the answer to this very modern problem might lie in the wisdom of the past.”

“We will now concentrate on the purification and identification of these antibiotics. We have also discovered additional antibacterial organisms from the same soil cure which may cover a broader spectrum of multi-resistant pathogens.”

The paper “A Novel Alkaliphilic Streptomyces Inhibits ESKAPE Pathogens” has been published in the journal Frontiers in Microbiology.

Blood.

Cell-membrane-coated nanobots successfully clear out 66% of bacteria and toxins in blood samples

Medical nanobots are one step closer, as researchers developed simple nanorobots that can be propelled through blood to clear out bacteria and toxins.

Blood.

Image credits Mate Marschalko / Flickr.

A team of engineers from the University of California San Diego has developed a class of ultrasound-powered robots that can scrub blood clean of bacteria and the toxins they produce. While still simple, the proof-of-concept nanobots could pave the way towards safe and rapid methods of decontaminating biological fluids — even in the bodies of living patients.

Bling medicine

The team builds their nanorobots out of gold nanowires coated with platelet and red blood cell membranes. This hybrid membrane is what gives the nanites the ability to clear out biological contaminants. The platelet membrane binds to pathogens such as the antibiotic-resistant strain of Staphylococcus aureus, MRSA, while the red blood cell membranes can absorb and neutralize toxins produced by bacteria.

The gold nanobody is what lets the researchers move the bots around. The metal responds to ultrasound, giving the team the means to power them through the bloodstream without the use of engines or fuel. The bots need to be mobile in order to more efficiently mix with a fluid sample, speeding up the process of detoxification.

The nanobots were created using processes pioneered by the teams of Joseph Wang and Liangfang Zhang, professors in the Department of NanoEngineering at the UC San Diego Jacobs School of Engineering. Wang’s team designed and built the nanobots and the means of ultrasound-powered propulsion, while Zhang’s team developed the process used to coat these in natural cell membranes.

“By integrating natural cell coatings onto synthetic nanomachines, we can impart new capabilities on tiny robots such as removal of pathogens and toxins from the body and from other matrices,” said Wang.

“This is a proof-of-concept platform for diverse therapeutic and biodetoxification applications.”

Furthermore, the natural membranes prevent the nanobots from being ‘biofouled’ — a process by which proteins cake onto the surface of a foreign body, which would prevent the nanobots from functioning. The hybrid membranes were created from natural membranes, separated in one piece from platelets and red blood cells. These were then blasted with high-frequency sound waves, causing them to fuse together.

Nanobot.

The nanobot binding to and isolating a pathogen.
Image credits Fernández de Ávila et al., 2018, Science Robotics.

The robots’ bodies were constructed by then applying these membranes to gold nanowires through chemical means.

The finished devices are roughly 25 times smaller than the width of a hair, the team writes. Ultrasound waves can propel them up to 35 micrometers per second in blood. They were successful in cleaning blood samples contaminated with MRSA and associated toxins — after 5 minutes of being injected, the levels of bacteria and toxins were three times lower in treated samples than untreated samples.

If you’re like me and dream all starry-eyed about the day we’ll treat ourselves with nanobots, this research might make you feel quite happy inside. However, this work is at a very early stage. It’s also focused on something different — the team notes that, while their current nanobots can be used to treat MRSA in blood samples, they aim to have a device that can detoxify all kinds of biological fluids.

We still have a ways to go until then. For the near future, the team hopes to test their devices in live animal models, and to devise a way of creating the robot bodies out of biodegradable materials instead of gold.

The paper “Hybrid biomembrane–functionalized nanorobots for concurrent removal of pathogenic bacteria and toxins” has been published in the journal Science Robotics.

MRSA.

Methicillin-resistant Staphylococcus aureus (MRSA) uses our body’s fats to ward off treatment

As antibiotic-resistant pathogens encroach on our hospitals, one team is trying to strip MRSA of its defenses.

MRSA.

Methicillin resistant Staphylococcus aureus (MRSA) magnified 20,000 times under the scanning electron micrograph. Image credits Janice Carr.

People don’t oft think about this, but the way we treat diseases and pathogens today wouldn’t have been just a luxury for people 100, 150 years ago — it would have been a straight-up miracle dripped from the heavens, day in, day out. We owe this ability to casually swallow a teeny tiny white tablet and then walk away from deadly infections to how effective modern antibiotics are at killing germs.

But said germs are evolving to become immune to these compounds — and once they do, they’ll come at us with a vengeance.

New rules of engagement

One of the best-known and most widely seen antibiotic resistant pathogen is known as MRSA — methicillin-resistant Staphylococcus aureus. This bacterium, which can easily turn routine medical operations into life-and-death battles, is responsible for most of the 30,000 deaths annually associated with antibiotic-resistant infections in the U.S. alone.

MRSA owes this infamous achievement to its resilience and, frankly, a kind of bacterial ingenuity that lets it shrug off should-be-deadly antibiotics. New research at the Michigan State University, however, is figuring out how to turn one of its strengths against it.

“Attacking the cell membrane and inhibiting its ability to produce lipids, or fats, could be an effective treatment protocol,” said senior author Neal Hammer, MSU assistant professor of microbiology and molecular genetics.

“MRSA, though, bypasses the effects of fatty acid inhibitors by absorbing human lipids.”

The study is based on previous research, which found that MRSA has a fat-absorbing pathway encoded in its genes. The problem with such a pathway is that most of our antibiotics work by destabilizing bacterial cell walls (made of fat molecules). MRSA’s adaptation to antibiotics is especially problematic since it doesn’t simply make our drugs somewhat less effective — it renders most of them completely pointless.

MRSA can absorb fat from the host organism, and then use it as a shield. In the case of us humans, it’s likely using fats (lipids) floating around in the bloodstream. These include compounds such as cholesterol that are a natural (and ample) component in our blood. The team suggests that MRSA can absorb and then integrate these substances into its own membranes. The process makes it virtually immune to antibiotics that work by blocking fatty acid synthesis pathways.

“MRSA secretes enzymes, called ‘lipases,’ that free the fatty acids in human LDLs, or bad cholesterol,” Hammer said. “We used mass spectrometry to identify how MRSA was able to perform this feat — the first time this process has been observed.”

Past research focused on MRSA’s interaction to fatty acids found on the skin — as much as 30% of the world’s population carry MRSA on their skin without any adverse health effects. The present study is the first to identify how MRSA can draw fatty acids from inside the host body and the mechanisms that allow it to do so.

Hammer says he and his team will focus their future research on how to prevent MRSA from drawing these fats from the ones it infects. If successful, the findings could make our antibiotics effective against staph yet again.

The paper “Staphylococcus aureus Utilizes Host-Derived Lipoprotein Particles as Sources of Fatty Acids” has been published in the Journal of Bacteriology.

Livestock-MRSA found in British-sourced pork at Asda and Sainsbury’s

British-grown pork livestock has been tested positive for livestock associated MRSA, the Guardian reports. The tests were carried out by Dr Mark Holmes, director of studies in clinical veterinary medicine at Churchill College, Cambridge University, and commissioned by the Alliance to Save Our Antibiotics, founded by the Soil Association, Compassion in World Farming and Sustain.

Image credits Tanakawho / Flickr.

Out of a sample of 97 UK-grown-pork products purchased from British supermarkets, three items — sourced from Asda and Sainsbury’s — were contaminated with MRSA CC398, a livestock strain of the superbug, the publication reports. Working with the Bureau of Investigative Journalism (BIJ), the Guardian has identified the most likely source of the infection in import-legislature loopholes. Through these, pigs from countries where the bacteria is rampant, such as Denmark, have been imported to the UK without proper precautions.

And that’s really bad news.

While MRSA CC398 isn’t as harmful to us as the human-specific strains, it’s still a potentially deadly bacteria that can resist almost everything we can throw at it. Research has found that combining three previously-efficient drugs together can serve as a sort of stop-gap measure against the bacteria; there’s also a thousand year-old salve that’s shown some potential agains MRSA, and Canadian clay. And that’s it.

About 300 people die each year as result of MRSA infection in England and Wales alone, and the bug seriously threatens patients with weakened immune systems.

“MRSA infections kill 11,000 people each year in the United States, and the pathogen is considered one of the world’s worst drug-resistant microbes,” said Gautam Dantas, PhD, an associate professor of pathology and immunology at the Washington University School of Medicine, unaffiliated with the publication.

Still, six cases of MRSA CC398 death have been confirmed in Denmark so far, but there are probably a lot more, the Guardian reports. Animals can catch the bacteria from infected pigs, and people can contract it from eating infected meat or from working with infected animals. Thoroughly cooking it should destroy the germs, but a small risk remains.

The publication warns that UK pigs might be in for the same fate as Denmark’s, where MRSA CC389 spread over a decade ago and now afflicts two-thirds of farms. It’s a major health issue for the country, with some 12,000 people believed to have contracted it — and there are no screening programs set in place for danish pigs.

“If we don’t have tight infection control and we don’t try to control the movement of live animals, infection can spread. The British are up in arms about the movement of people, but the EU also has a large movement of animals,” said Prof Tim Lang from the Food Policy at City University, London.

“We need biosecurity, we need to tighten up this livestock movement. You may get cheap meat, but in the long term it’s going to add to your public health problems.”

The real issue here, just like with human-specific MRSA, is the drug resistance part. What most people don’t understand is that it’s not limited to humans — it’s happening in agriculture, too. The rise of the CC398 strain can in part be attributed to an overuse of antibiotics in factory farming, where cramped and dirty conditions allows disease to flourish. Farmers are left with little choice but feed their livestock huge amounts of antibiotics, promoting the rise of drug resistance at a much higher rate than those seen in humans. And if the bacteria gains a foothold in the UK (and there’s not much we can do to spot it apart from screenings) our drugs won’t be able to destroy it. So even such a low number of cases is worrying.

Where’s it coming from?

The Guardian reports that last year, out of 100 samples of pork from UK supermarkets, nine were found to contain MRSA. One of these was sourced from an Irish farm, and the others from pigs in Denmark. The findings marked the first confirmed occurrence of the superbug in the UK.

Image credits Tim Geers / Flickr.

While it’s impossible to determine if the meat tested now comes from UK or imported pigs, it does show that the bacteria is present in UK farms. Imports are likely the original source of the infection, The Guardian adds. At least one Danish farm has been found to be a regular supplier of importer pigs to the UK even if their pigs were contaminated with MRSA in 2014, the BIJ reported. The company, Breeding Centre Rønshauge A/S, refused to say how many pigs it had exported to the UK and whether they could have been contaminated. But official export figures show that the company supplied 41 pigs to the UK in July this year, 65 in 2013 and 16 in 2012. The UK government does not screen for the infection in imported animals, citing a low risk of serious illness.

“It is extremely worrying to find LA [livestock-associated]-MRSA in British-produced pork,” said Emma Rose, from the Alliance to Save Our Antibiotics.

“Scientists are now warning that the extensive MRSA reservoir in animals could ultimately lead to a pandemic spread in the human population. LA-MRSA is able to cause serious and potentially fatal infections in humans, and as the bacteria is resistant to antibiotics, it is extremely difficult to treat. What’s more, even more dangerous variations are emerging as the superbug evolves.”

The Department for Environment, Food and Rural Affairs (Defra) said that LA-MRSA “is not the same as MRSA strains that can cause healthcare-associated infections” if the meat isn’t properly cooked, and the risk to people is “low”. Defra and the National Pig Association recommend that all pigs imported to Britain be screened for the bacteria.

“The government is reviewing options for surveillance, which will be proportionate to the very low health risk posed by livestock-associated MRSA.”

When animals are imported, they’re screened for multiple diseases, but the one for CC398 is voluntary. So there’s no way to know how many infected pigs there are in UK right now. There have been two confirmed cases, one in Northern Ireland and one in eastern England, but without any systematic tests carried out in farms, all we’re left with are extremely rough estimations. The publication says that this and other health concerns related to UK meat come down to pressure towards factory farms producing the cheapest possible meat.

Trio of individually ineffective drugs efficiently kills MRSA in mice

A research team has demonstrated the effectiveness of a 3-antibiotic cocktail that kills methicillin-resistant Staphylococcus aureus, or MRSA, in all mice that were treated with it.

Scanning electron micrograph of a human neutrophil ingesting MRSA. Image via Wikipedia.

MRSA is a bacterium responsible for several difficult-to-treat infections in humans. MRSA is especially threatening in hospitals, prisons and nursing homes, where patients with open wounds or invasive devices generally have weakened immune systems and are at a much greater risk of infection.

The research team has been working with antibiotics that are ineffective against specific pathogens that have evolved to resist them; the three antibiotics they used are meropenem, piperacillin and tazobactam, although practically, they can be considered two drugs, since piperacillin and tazobactam together make up Zosyn. Although these antibiotics are strong injectables, they have no effect on MRSA individually – but together, they work.

“This three-drug combination appears to prevent MRSA from becoming resistant to it,” said Dr. Gautam Dantas, an associate professor of pathology and immunology, in a press release. “We know all bacteria eventually develop resistance to antibiotics, but this trio buys us some time, potentially a significant amount of time.”

They tested the drug combination on 73 different strains of the MRSA microbe, and it worked against all of them, curing the infection. There was also no indication that the bacterium was developing resistance to the drugs.

The results were so promising that the team are looking to test the cocktail in humans as soon as possible.

“MRSA infections kill 11,000 people each year in the United States, and the pathogen is considered one of the world’s worst drug-resistant microbes,” said principal investigator Gautam Dantas, PhD, an associate professor of pathology and immunology. “Using the drug combination to treat people has the potential to begin quickly because all three antibiotics are approved by the FDA.”

The study is published in Nature: Chemical Biology.