Micro Eclectics

Once considered rare, mitochondrial diseases are now thought to affect as many as one person in 5,000. New research in this area hopes to open up more opportunities for predicting a child's risk of developing a mitochondrial disease which can cause muscle weakness, diabetes, strokes, heart failure and epilepsy. All human and animal cells contain many mitochondria, which are involved in energy production within the body. Mitochondria have their own genetic information, known as mitochondrial DNA, or mtDNA, which is inherited. A child only inherits one copy of DNA from each parent but may inherit many copies of mtDNA, which are only passed down from the mother. Scientists have shown for the first time how this particular family of diseases are passed down from mother to child and how this can lead to the severity of the disease differing widely. Mutations in mtDNA can affect energy production within cells and therefore lead to disease. However, mitochondrial diseases...

Bacteria that manufacture hydroxyapatite (HA) could be used to make stronger, more durable bone implants. Professor Lynne Macaskie from the University of Birmingham this week (7-10 September) presented work to the Society for General Microbiology’s meeting at Heriot-Watt University, Edinburgh. Using Serratia bacteria, the research showed that the bacterial cells stuck tightly to surfaces such as titanium alloy, polypropylene, porous glass and polyurethane foam by forming a biofilm layer containing biopolymers that acted as a strong adhesive. The HA coating then builds up over the surface. For practical use, the HA layer must stick tightly, then the material is dried and heated to destroy the bacteria. A micro-manipulation technique used to measure the force needed to overcome the bioglue adhesion showed that dried biofilm stuck 20-times more tightly than fresh biofilm. When coated with HA the adhesion was several times more again. Slightly roughening the surface made the...

B acteria that we carry in our bodies may help decide who we marry, according to a new study that analyzes the gut of...a small fruit fly. A group of molecular biologists recently demonstrated that the symbiotic bacteria inside a fruit fly greatly influence its choice of mates.  They propose that the basic unit of natural selection is not the individual living organism, plant or animal, but rather a larger biological milieu called a holobiont. This milieu can include plant or animal life as well as their symbiotic partners. In the case of animals, these partners tend to be microorganisms like intestinal bacteria. The first experiment repeated a study carried out two decades ago by a Yale University researcher, in which a fly population was divided in half and fed different diets ― malt sugar versus starch. A year later, when the flies were re-integrated as one group, those who had been fed starch preferred starch-fed mates, while the sugar-fed flies preferred mate...

Toxoplasmosis is caused by the Toxoplasma gondii parasite, which experts estimate infects 30 to 50 percent of the global population. The infection is also found in animals, especially domestic cats and people contract the parasite mostly by eating the poorly cooked flesh of infected animals or through contact with cat feces. The infection causes mild flu-like symptoms in adults and otherwise healthy people before entering a chronic and dormant phase, which has previously been regarded as symptom-free. It is, however, known that toxoplasmosis in the brain can be fatal in people with depleted immune defence and in fetuses, which can be infected through the mother. Because of this risk, pregnant women are recommended to avoid contact with cat litter trays. A number of studies have been presented in recent years showing that the toxoplasmosis parasite affects its host even during the dormant phase. It has, for example, already been observed that rats become unafraid of cats...

Cleaner drinking water with fewer chemicals may be made possible using ... bacteria. A research team studied four bacteria, Sphingobium, Xenophilus, Methylobacterium and Rhodococcus, found in a city's drinking water to see which combinations were more likely to produce a 'biofilm'. Biofilms are layers of bacteria which form on the inner surfaces of water pipes. Like in many instances, bacteria can be harmful or not. "If the bacterial growth is too heavy, it can break off into the water flow, which at best can make water discoloured or taste unpleasant and at worst can release more dangerous bacteria. Our research looks at what conditions enable biofilms to grow, so we can find ways to control the bacteria in our water supply more effectively," explains lead researcher Professor Catherine Biggs. The researchers isolated four bacteria from water taken from a domestic tap: two were widely found in drinking water everywhere, one was less common and on...

Breast-feeding is back. When it comes to early establishment of gut and immune health for babies, 'breast is best' according to a new study of how 'good' bacteria arrive in babies' digestive systems. How babies acquire a population of good bacteria can also help to develop formula milk that more closely mimics nature.  The researchers found the same strains of Bifidobacterium breve and several types of Clostridium bacteria, which are important for colonic health, in breast milk, and maternal and/or neonatal faeces. Strains found in breast milk may be involved in establishing a critical nutritional balance in the baby's gut and may be important to prevent intestinal disorders. Professor Christophe Lacroix at the Institute for Food, Nutrition and Health, ETH-Zurich, Switzerland, said,"We are excited to find out that bacteria can actually travel from the mother's gut to her breast milk. A healthy community of bacteria in the gut of both mo...

The Toxoplasma parasite has been linked spontaneous abortion in pregnant women and killing immune-compromised patients, but it has even stranger effects in mice. Infected mice lose their fear of cats. That's good for cats and then for the parasite, because the cat gets an easy meal and the parasite gets into the cat's intestinal track, the only place it can sexually reproduce and continue its cycle of infection. New research reveals a scary twist to this scenario: the parasite's effect seem to be permanent. The fearless behavior in mice persists long after the mouse recovers from the flu-like symptoms of toxoplasmosis, and for months after the parasitic infection is cleared from the body. A mouse infected with the Toxoplasma parasite loses its fear of cats, which is good for both the parasite and the cat. The cat gets an easy meal, while the parasite gets into the cat's intestinal system, the only place it can sexually reproduce and complete its cy...

Researchers have linked Prevotella copri , a species of intestinal bacteria, to the onset of rheumatoid arthritis, the first demonstration in humans that the chronic inflammatory joint disease may be mediated in part by specific intestinal bacteria. Rheumatoid arthritis, an autoimmune disease that attacks joint tissue and causes painful, often debilitating stiffness and swelling, affects 1.3 million Americans. It strikes twice as many women as men and its cause remains unknown although genetic and environmental factors are thought to play a role. It is treated with an assortment of medications, including antibiotics, anti-inflammatory drugs like steroids, and immunosuppressive therapies that tame immune reactions. Little is understood about how these medications affect gut bacteria. Using DNA analysis to compare gut bacteria from fecal samples of patients with rheumatoid arthritis and healthy individuals, the researchers found that P. copri was more abundant i...

Modern science has made it possible to synthesize increasingly targeted drugs but Ma Nature is not out of it yet - it just took science to discover what nature could do. Pyridomycin, a substance produced by non-pathogenic soil bacteria, has been found to be a potent antibiotic against a related strain of bacteria that cause tuberculosis. The Ecole Polytechnique Fédérale de Lausanne scientists who discovered this property now have a better understanding of how its complex, three-dimensional structure allows it to act simultaneously on two parts of a key enzyme in the tuberculosis bacillus, and in doing so, dramatically reduce the risk that the bacteria will develop multiple resistances. Stewart Cole, director of EPFL's Global Health Institute, led a team that discovered the anti-tuberculosis effect of pyridomycin in 2012. By inhibiting the action of the "InhA" enzyme, pyridomycin literally caused the thick lipid membrane of the bacterium to burst. Now the ...

Some bacteria achieve resistance to antibiotics through mutation but other types of bacteria, known as 'persistent' bacteria, are not resistant to the antibiotics but simply continue to exist in a dormant or inactive state while exposed to antibacterial treatment. These bacteria later 'awaken' when that treatment is over, resuming their work. It was known that there is a connection between these kind of bacteria and the naturally occurring toxin HipA in the bacteria, but scientists did not know the cellular target of this toxin and how its activity triggers dormancy of the bacteria. Recently, Hebrew University researchers led by Prof. Gadi Glaser of the Faculty of Medicine and Prof. Nathalie Balaban of the Racah Institute of Physics have been able to demonstrate how this happens. Their research showed that when antibiotics attack these bacteria, the HipA toxin disrupts the chemical “messaging” process necessary for nutrients to build proteins. This is inte...

As if pretty people didn't have enough advantages, they may also give us a glance at their reproductive health, according to a paper in the American Journal of Human Biology reveals a link between Body Mass Index (BMI) and the amount of bacteria colonizing noses. The results show that heavier men harbor more potentially pathogenic species of bacteria in their nose, compared with slimmer, more traditionally attractive men. "According to an evolutionary point of view, traits related to attractiveness are supposed to be honest signals of biological quality," according to lead author Dr. Boguslaw Pawlowski of the University of Wroclaw. "We analyzed whether nasal and throat colonization with potentially pathogenic bacteria is related to body height and BMI in both sexes." 103 healthy females and 90 healthy males (mean age of 21.4 and 22.8, respectively - college students are always available) participated in the study. Heights and weights were self-...

It's broadly understood that the world's oceans play a crucial role in the global-scale cycling and exchange of carbon between Earth's ecosystems and atmosphere. Now scientists at Scripps Institution of Oceanography at UC San Diego have taken a leap forward in understanding the microscopic underpinnings of these processes. When phytoplankton use carbon dioxide to make new cells, a substantial portion of that cellular material is released into the sea as a buffet of edible molecules collectively called "dissolved organic carbon." The majority of these molecules are eventually eaten by microscopic marine bacteria, used for energy, and recycled back into carbon dioxide as the bacteria exhale. The amount of carbon that remains as cell material determines the role that ocean biology plays in locking up atmospheric carbon dioxide in the ocean. Thus, these "recycling" bacteria play an important role in regulating how much of the planet's ca...

Smallpox as a disease is dead and has been since 1980. Should we let the virus behind it die? Variola, the virus that causes smallpox, is on the agenda of the upcoming meeting of the World Health Assembly (WHA), the governing body of the World Health Organization, which is part of the United Nations. The UN would like to destroy the last known remaining live strains of the virus  but an international group of scientists led by Inger Damon, from the US Centers for Disease Control and Prevention, argue that the WHA should not choose destruction, because crucial scientific questions remain unanswered and important public health goals unmet. Smallpox was declared eradicated in 1980, the only human pathogen for which successful eradication has been achieved to date. Since then, limited research focusing on diagnostic, antiviral and vaccine development, under close direction and oversight, has continued in two high-security laboratories--one in Russia and one in the US...

A bacterium whose genetic material includes an added pair of DNA "letters," or bases, not found in nature has been created. The cells of this unique bacterium can replicate the unnatural DNA bases more or less normally, for as long as the molecular building blocks are supplied. The team of researchers behind this have been working since the late 1990s to find pairs of molecules that could serve as new, functional DNA bases—and, in principle, could code for proteins and organisms that have never existed before. The task hasn't been a simple one. Any functional new pair of DNA bases would have to bind with an affinity comparable to that of the natural nucleoside base-pairs adenine–thymine and cytosine–guanine. Such new bases also would have to line up stably alongside the natural bases in a zipper-like stretch of DNA. They would be required to unzip and re-zip smoothly when worked on by natural polymerase enzymes during DNA replication and transcription int...

Schistosomiasis is a parasitic disease that infects 243million people worldwide, and kills about 200 thousand every year. Theinfection is contracted through contaminated waters, and in the developingworld, where is most common, is 2nd only to malaria in rates of infection andpublic health impact. To make things worse, women, already one of the most vulnerable groups in these regions, often develop infertility secondary to the infection, with the parasite being a main cause for the problem in these regions . Places where female role is centred on being a mother, and gynaecological medical care is next to inexistent.  But there is good news from a study by scientists in Portugal and Angola: Julio Santos, Monica Botelho and colleagues have found catechols ( molecules similar to oestrogen, the female sex hormone) in the urine of infected females, that seem to be produced by the parasite and associated with the infertility. If theseresults are confirmed - and catech...

Methicillin-resistant Staphylococcus aureus (MRSA) has become the poster child for antibiotic resistance in large part because of a larger problem: patients tend to stop taking antibiotics once they feel better. In such instances, the surviving bacteria may become impervious to the drugs designed to fight them.  A single-dose antibiotic could fix that and a new one, oritavancin, is as effective in the battle against stubborn skin infections as a twice-daily infusion given for up to 10 days, according to a recent large study. The three-year study of oritavancin that encompassed two large clinical trials enrolling nearly 2,000 patients. Findings from the trials will be presented to the U.S. Food and Drug Administration as part of the drug's approval application but results for the first of the two clinical trials, which included 475 patients randomized to take the investigational drug, and 479 patients following a typical regimen of vancomycin, i...

Smartphones are everywhere, and they may tell something about you that you didn't realize could be told. When we touch things we give it our 'germs' and that knowledge could tell researchers something about our personal microbial world. Our phones can be biological and environmental sensors. To test our biological connection with phones, University of Oregon researchers sequenced microbes from the dominant-hand index fingers and thumbs of 17 subjects and from the touchscreens of their smartphones, during a recent Robert Wood Johnson Foundation workshop in Princeton, New Jersey. Our cell phones reflect the personal microbial world of their owners with potential implications for their use as bacterial and environmental sensors. Credit: James Meadow The study found smartphones closely resembled the microbiome sampled from their owner's finger, with 82 percent of the most common bacteria on participants' fingers also found on their phones. Interes...

By revealing the mechanisms that allow the bacteria to rapidly clog up medical devices, a group of researchershas moved a step closer to preventing infections of the common hospital pathogen, Staphylococcus aureus . The researchers have shown that the bacteria colonizes into large groups, called biofilms, using a biological glue, and form thin, slimy, thread-like structures called streamers. The streamers adhere to a surface and are able to trap passing cells as they flow through medical devices such as stents and catheters, becoming more rigid and eventually clogging up the whole device. In their study, the researchers, from Princeton University, recreated the physical environments of medical devices with curvy channels, multiple networks and a flowing fluid, and showed that streamers can rapidly expand and create a blockage in a surprisingly short space of time. Moreover, if the surfaces were coated with human blood plasma, which the bacteria often encounter in ...

Chlorinated chemicals perform a host of societally useful functions, but they're not perfect. Once their use life has ended, they can become environmental contaminants and even resistant to bioremediation. In a series of new studies, Anca Delgado, a researcher at Arizona State University's Biodesign Institute, examines unique groups of microorganisms, capable of converting hazardous chlorinated chemicals like trichloroetheene (TCE) into ethene, a benign end product of microbial biodegradation. The new studies explore the metabolic activities of a group of microbes known as Dehalococcoides , and propose strategies to improve their effectiveness for environmental cleanup projects involving chlorinated chemicals. Trichloroethene – focus of the current studies – is one of the most ubiquitous chlorinated chemicals. Approximately 60 percent of the U.S. National Priorities List Superfund sites and roughly 20 percent of the national groundwater sources are contaminated ...

Probiotics are a popular fad but there is little evidence they are anything more than a well-marketed placebo. Like homeopathy, at least that means the only harm will be in your wallet. Yet when something of undetermined benefit becomes a mullti-billion dollar market, scientists are going to take a look. The National Center for Complementary and Alternative Medicine isn't doing the first nationwide clinical trial to determine if probiotics work, they're busy spending $120 million a year endorsing herbs, it's instead funded by the National Institutes of Health to determine if one of the most commonly used probiotics can safely and effectively treat infants and toddlers suffering from acute gastroenteritis, otherwise known as stomach virus or “stomach flu.” Why? Because people claim it works. Probiotics are live microorganisms that companies claim can restore the balance of intestinal bacteria and increase resistance to harmful germs. They are added to some...

We all know what happens to us when we get sick, but at least we have a microbiota to protect us. What happens when those ecosystem bacteria colonizing our guts gets hit with infection? A new computational models showed how infection can affect bacteria that naturally live in our intestines, which may help clinicians to better treat and prevent gastrointestinal infection and inflammation through a better understanding of the major alterations that occur when foreign bacteria disrupt the gut microbiota. "Our gut contains ten-times more bacterial cells than there are human cells in our body," said Lynn Bry, MD, PhD, director of the BWH Center for Clinical and Translational Metagenomics, senior study author. "The behavior of these complex bacterial ecosystems when under attack by infection can have a big impact on our health." Citrobacter rodentium bacterial cells (reddish-brown) reside alongside commensal flora (black rods) in the colon. Image cou...

The Centers for Disease Control and Prevention is rightfully concerned that the U.S. faces “potentially catastrophic consequences” from the growing threat of antibiotic-resistant infections, which kill about 23,000 Americans a year. One solution is personalized antibiotic therapy, but that would require both rapid bacterial identification and narrow-spectrum antibiotics. Tailored antibiotic therapy would not only extend the clinical lifetime of new antibiotics by better managing resistance, it might also revive old antibiotics that have been abandoned due to resistance, toxicity, or their inability to penetrate bacterial membranes. Timothy Wencewicz, PhD, assistant professor of chemistry in Arts&Science at Washington University in St. Louis, is working on a drug delivery system that would target specific bacteria by exploiting small molecules called siderophores they secrete to scavenge for iron in their environment. Each bacterium has its own system of sideropho...

A parasitic fungus - Ophiocordyceps camponoti-rufipedis , known as the "zombie ant fungus" - must kill its ant hosts outside their nest to reproduce and transmit their infection,so they manipulate its victims to die in the vicinity of the colony, ensuring a constant supply of potential new hosts, according to a new paper.  Previous research shows that zombie ant fungi control the behavior of carpenter ant workers -- Camponotus rufipes -- to die with precision attached to leaves in the understory of tropical forests, noted study lead author Raquel Loreto, doctoral candidate in entomology, Penn State's College of Agricultural Sciences. "After climbing vegetation and biting the veins or margins on the underside of leaves, infected ants die, remaining attached to the leaf postmortem, where they serve as a platform for fungal growth," Loreto said. Zombie ant fungus grows from the cadaver and produces spores, which rain down on the forest floor to in...

India has emerged as the world's largest consumer of antibiotics, with a 62% increase in use over the past decade. 'Global Trends in Antibiotic Consumption, 2000-2010', a study by scientists from Princeton University, has found that worldwide antibiotic use has risen by 36% over those 10 years, with five countries — Brazil, Russia, India, China and South Africa (BRICS) — responsible for more than three-quarters of that surge. Among the 16 groups of antibiotics studied, cephalosporins, broad-spectrum penicillins and fluoroquinolones accounted for more than half of that increase, with consumption rising 55% from 2000 to 2010. During this period, India's antibiotic use went up from eight billion units (2001) to 12.9 billion units (2010). The study quantifies the growing alarm surrounding antibiotic-resistant pathogens and a loss of efficacy among antibiotics used to combat the most common illnesses. It confirms an increasing resistance to carbapenems and p...

  In a breakthrough, scientists have developed a modified version of a bacteria that produces a strong and precisely targeted anti-tumour response in rats, dogs and humans. In its natural form, Clostridium novyi (C novyi) is found in the soil and, in certain cases, can cause tissue-damaging infection in cattle, sheep and humans. The microbe thrives only in oxygen-poor environments, which makes it a targeted means of destroying oxygen-starved cells in tumours that are difficult to treat with chemotherapy and radiation, researchers said. Researchers at the Johns Hopkins Kimmel Cancer Centre removed one of the bacteria's toxin-producing genes to make it safer for therapeutic use. They tested direct-tumour injection of the C novyi-NT spores in 16 pet dogs that were being treated for naturally occurring tumours. Six of the dogs had an anti-tumour response 21 days after their first treatment. Three of the six showed complete eradication of their tumours, and the len...