Tag Archives: bacteria

Human Gene Origins: 37% Bacterial, 35% Animal, 28% Eukaryotic

The percent of human genes that emerged in various stages of evolution: 37% bacterial, 28% eukaryotic, 16% animal, 13% vertebrate, 6% primate. The history that brought us to where we are is amazing. Eukaryotes include animals, plants, amoebae, flagellates, amoeboflagellates, fungi and plastids (including algae). So eukaryotic genes are those common to us and other non-animal eukaryotes while those classified as animal genes are shared by animals but not non-animal eukaryotes.

We are living in a bacterial world, and it’s impacting us more than previously thought by Lisa Zyga

Bacterial signaling is not only essential for development, it also helps animals maintain homeostasis, keeping us healthy and happy. As research has shown, bacteria in the gut can communicate with the brain through the central nervous system. Studies have found that mice without certain bacteria have defects in brain regions that control anxiety and depression-like behavior. Bacterial signaling also plays an essential role in guarding an animal’s immune system. Disturbing these bacterial signaling pathways can lead to diseases such as diabetes, inflammatory bowel disease, and infections. Studies also suggest that many of the pathogens that cause disease in animals have “hijacked” these bacterial communication channels that originally evolved to maintain a balance between the animal and hundreds of beneficial bacterial species.
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Scientists have also discovered that bacteria in the human gut adapts to changing diets. For example, most Americans have a gut microbiome that is optimized for digesting a high-fat, high-protein diet, while people in rural Amazonas, Venezuela, have gut microbes better suited for breaking down complex carbohydrates. Some people in Japan even have a gut bacterium that can digest seaweed. Researchers think the gut microbiome adapts in two ways: by adding or removing certain bacteria species, and by transferring the desired genes from one bacterium to another through horizontal gene transfer. Both host and bacteria benefit from this kind of symbiotic relationship, which researchers think is much more widespread than previously thought.
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We want badly for the message in ‘Animals in a bacterial world,’ to be a call for the necessary disappearance of the old boundaries between life science departments (e.g., Depts of Zoology, Botany, Microbiology, etc.) in universities, and societies (e.g., the American Society for Microbiology, etc.). We also want the message disseminated in college and university classes from introductory biology to advanced courses in the various topic areas of our paper.”

Very cool stuff. This amazing facts scientists discover provide an amazing view of the world we live in and how interconnected we are to other life forms in ways we don’t normally think of.

Scientific Illiteracy Leads to Failure to Vaccinate Which Leads to Death

Anti-vaccination propagandists help create the worst whooping cough epidemic in 70 years by Steven Salzberg is a professor at Johns Hopkins School of Medicine:

When the vaccination rates drop, everyone becomes more vulnerable to infectious diseases. When more than 90% of the population is vaccinated, we have “herd immunity” – this means the disease can’t spread because there aren’t enough susceptible people in the community. So the high rate of vaccine refusal in Washington makes it easier for whooping cough (and other diseases) to spread.
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And now we learn that the U.S. is in the midst of the worst whooping cough epidemic in 70 years. One of the most hard-hit states is Washington, which the CDC just announced (on 20 July) has suffered 2,520 cases so far this year, a 1300% increase over last year. This is the highest number of cases reported in Washington since 1942.
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The U.S. has had over 17,000 cases this year, putting it on track for the worst year since 1959. The highest rate of infection in the nation is in Wisconsin (which has also been hit hard by anti-vaccine effects), followed by Washington and Montana. 10 deaths have been reported, mostly in infants who were too young to be vaccinated. For all this, we can thank the anti-vaccination movement.

The failure of our society to appreciate the value of science has dire consequences. We are lucky to benefit from the results of scientific advances around us everyday. Some people, instead of appreciating the value of science waste these great gifts we have been given.

What people want to believe is up to them. When people’s actions risk others lives that is not ok. Drunk drivers risk others lives; therefore we don’t allow drunk driving. Society requires that people respect others right to live. It is sensible to require people to cooperate to limit damaging behavior: such as drunk driving or not being properly vaccinated.

Pertussis (whooping cough) is a highly contagious bacterial disease that causes uncontrollable, violent coughing. The coughing can make it hard to breathe. Pertussis, or whooping cough, is an upper respiratory infection caused by the Bordetella pertussis or Bordetella parapertussis bacteria. It is a serious disease that can cause permanent disability in infants, and even death.

Our Dangerous Antibiotic Practices Carry Great Risks

Our continued poor antibiotics practices increase the risk of many deaths. We are very poor at reacting to bad practices that will kill many people in the future. If those increased deaths happened today it is much more likely we would act. But as it is we are condemning many to have greatly increased odds of dying from bacterial causes that could be prevented if we were more sensible.

Resistance to antibiotics is becoming a crisis

Increasingly, microbes are becoming untreatable. Margaret Chan, director general of the World Health Organization, warned in March of a dystopian future without these drugs. “A post-antibiotic era means, in effect, an end to modern medicine as we know it,” she said. “Things as common as strep throat or a child’s scratched knee could once again kill.”
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evidence is mounting that antibiotics are losing efficacy. Through the relentless process of evolution, pathogens are evading the drugs, a problem known broadly as antimicrobial resistance.
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Europe has launched a $741 million, seven-year, public-private collaborative research effort to accelerate drug development.

Seeking new antibiotics is wise but the commentary completely ignores our bad practices that are causing the problem to be much worse than it would be if we acted as though bad practices that will lead to many deaths should be avoided.

Previous posts about practices we taking that create great risk for increased deaths: Antibiotics Too Often Prescribed for Sinus Woes (2007) – Meat Raised Without Antibiotics is Sadly Rare Today (2007) – Overuse of Antibiotics (2005) – CDC Urges Increased Effort to Reduce Drug-Resistant Infections (2006) – FDA May Make Decision That Will Speed Antibiotic Drug Resistance (2007) – Antibacterial Soaps are Bad (2007) – Waste Treatment Plants Result in Super Bacteria (2009) – Antibiotics Breed Superbugs Faster Than Expected (2010) – Antibiotics Use in Farming Can Create Superbugs (2010) – What Happens If the Overuse of Antibiotics Leads to Them No Longer Working? (2011) – Dangerous Drug-Resistant Strains of TB are a Growing Threat (2012)

Obviously bacteria evolve to survive the counter measures we currently have. The foolish practices of promoting ignorance of evolution leads to a society where the consequences of actions, and the presence of evolution, lead to bad consequences. We find ourselves in that society.

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The Appendix Serves As a Reservoir of Beneficial Bacteria

This is an interesting explanation for the purpose of the appendix.

The appendix does have a use – re-booting the gut

The US scientists found that the appendix acted as a “good safe house” for bacteria essential for healthy digestion, in effect re-booting the digestive system after the host has contracted diseases such as amoebic dysentery or cholera, which kill off helpful germs and purge the gut.

This function has been made obsolete by modern, industrialised society; populations are now so dense that people pick up essential bacteria from each other, allowing gut organisms to regrow without help from the appendix, the researchers said.

But in earlier centuries, when vast tracts of land were more sparsely populated and whole regions could be wiped out by an epidemic of cholera, the appendix provided survivors with a vital individual stockpile of suitable bacteria.

Using Nanocomposites to Improve Dental Filling Performance

After a dentist drills out a decayed tooth, the cavity still contains residual bacteria. Professor Huakun (Hockin) Xu says it is not possible for a dentist to remove all the damaged tissue, so it’s important to neutralize the harmful effects of the bacteria, which is just what the new nanocomposites are able to do.

Rather than just limiting decay with conventional fillings, the new composite he has developed is a revolutionary dental weapon to control harmful bacteria, which co-exist in the natural colony of microorganisms in the mouth.

“Tooth decay means that the mineral content in the tooth has been dissolved by the organic acids secreted by bacteria residing in biofilms or plaques on the tooth surface. These organisms convert carbohydrates to acids that decrease the minerals in the tooth structure,” says Xu, director of the Division of Biomaterials and Tissue Engineering in the School’s Department of Endodontics, Prosthodontics and Operative Dentistry.

The researchers also have built antibacterial agents into primer used first by dentists to prepare a drilled-out cavity and into adhesives that dentists spread into the cavity to make a filling stick tight to the tissue of the tooth. “The reason we want to get the antibacterial agents also into primers and adhesives is that these are the first things that cover the internal surfaces of the tooth cavity and flow into tiny dental tubules inside the tooth,” says Xu.

The main reason for failures in tooth restorations, says Xu, is secondary caries or decay at the restoration margins. Applying the new primer and adhesive will kill the residual bacteria, he says.

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Bacteria In Cave Isolated for 4 Million Years Highly Resistant to Many Antibiotics

PLoS published an interesting open access research paper on bacteria and their resistance to antibiotics. I am surprised how widespread and strong the antibiotic resistance was is the isolated bacteria that were studied. It raises more interesting questions about the important area of antibiotics.

The lead researcher on this study, Gerry Wright, previously published on antibiotic properties of bacteria found in soil.

Abstract of Antibiotic Resistance Is Prevalent in an Isolated Cave Microbiome

Antibiotic resistance is a global challenge that impacts all pharmaceutically used antibiotics. The origin of the genes associated with this resistance is of significant importance to our understanding of the evolution and dissemination of antibiotic resistance in pathogens. A growing body of evidence implicates environmental organisms as reservoirs of these resistance genes; however, the role of anthropogenic use of antibiotics in the emergence of these genes is controversial.

We report a screen of a sample of the culturable microbiome of Lechuguilla Cave, New Mexico, in a region of the cave that has been isolated for over 4 million years. We report that, like surface microbes, these bacteria were highly resistant to antibiotics; some strains were resistant to 14 different commercially available antibiotics. Resistance was detected to a wide range of structurally different antibiotics including daptomycin, an antibiotic of last resort in the treatment of drug resistant Gram-positive pathogens.

Enzyme-mediated mechanisms of resistance were also discovered for natural and semi-synthetic macrolide antibiotics via glycosylation and through a kinase-mediated phosphorylation mechanism. Sequencing of the genome of one of the resistant bacteria identified a macrolide kinase encoding gene and characterization of its product revealed it to be related to a known family of kinases circulating in modern drug resistant pathogens. The implications of this study are significant to our understanding of the prevalence of resistance, even in microbiomes isolated from human use of antibiotics. This supports a growing understanding that antibiotic resistance is natural, ancient, and hard wired in the microbial pangenome.

Dangerous Drug-Resistant Strains of TB are a Growing Threat

Drug-resistant strains of TB are out of control

The fight against new, antibiotic-resistant strains of tuberculosis has already been lost in some parts of the world, according to a senior World Health Organisation expert.
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Dr Paul Nunn, head of the WHO’s global TB response team, is leading the efforts against multi-drug resistant TB (MDR-TB). Nunn said that, while TB is preventable and curable, a combination of bad management and misdiagnosis was leaving pharmaceutical companies struggling to keep up. Meanwhile, the disease kills millions every year.

“It occurs basically when the health system screws up,” said Nunn. “Treating TB requires a carefully followed regime of medication over six months. In places where health services are fragmented or underfunded, or patients poor and health professionals ill-trained, that treatment can fall short, which can in turn lead to patients developing drug-resistant strains. It’s been estimated that an undiagnosed TB-infected person can infect 10 others a year.

We tend to do a poor job of dealing with systemic effects of poorly functioning systems. Direct present threats get out attention. And we are decent at directing brain power and resources to find solutions. We are not very good at dealing with failures that put us in much worse shape in the long term. For small threats we can wait until it becomes a present threat and then deal with it. There are costs to doing this (economic and personal) but it can be done.

Some problems though become enormously complicated to deal with once they become obvious. Global climate change, for example. And often, even once they are obvious, we won’t act until the costs (economic and in human lives) are very large. It is possible that once we decide to get serious about dealing with some of these issues that the costs (economic and in human lives) will be catastrophic.

The failure to use anti-biotics medicine properly is a very serious threat to become one of these catastrophic societal failures. While tuberculosis failures may be larger in poorer countries, rich countries are failing probably much more critically in the misuse of anti-biotics (I would guess, without having much evidence at my fingertips to back up my opinion. I believe the evidence exists I am just not an expert). These failures have huge costs for all of humanity but we are risking many premature deaths because we systemically fail to deal with issues until the consequences are immediate.

Bacteriophages Enter Bacteria Using an Iron Tipped Spike

Bacteria-Killing Viruses Wield an Iron Spike

Forget needles in haystacks. Try finding the tip of a needle in a virus. Scientists have long known that a group of viruses called bacteriophages have a knack for infiltrating bacteria and that some begin their attack with a protein spike. But the tip of this spike is so small that no one knew what it was made of or exactly how it worked. Now a team of researchers has found a single iron atom at the head of the spike, a discovery that suggests phages enter bacteria in a different way than surmised.

Wherever there are bacteria you will find bacteriophages; digestive tracts, contaminated water, and feces are usually a good start. These viruses begin their dirty work by drilling into the outer membrane of bacteria. Once completely through all of a bug’s defenses, the phages inject their DNA, which essentially turns the bacterium into phage-producing factories. Eventually, the microbes become filled with so many viruses that they burst, releasing a new horde of phages into the environment.

Bacteriophages are amazing. It is so interesting to learn about amazingly creative solutions that have evolved over time. Real-life science is not easy to match with fiction that springs from our imaginations.

Potential Antibiotic Alternative to Treat Infection Without Resistance

Researchers at the University of Michigan have found a potential alternative to conventional antibiotics that could fight infection with a reduced risk of antibiotic resistance. Sadly Michigan is another school that is allowing work of those paid for by the citizens of Michigan to be lock away, only due to the wishes of an outdated journal business model instead of supporting open science. The Big Ten seems much more interested in athletic riches than in promoting science. The Big Ten should be ashamed of such anti knowledge behavior and require open science for their schools if they indeed value knowledge.

By using high-throughput screening of a library of small molecules, the team identified a class of compounds that significantly reduced the spread and severity of group A Streptococcus (GAS) bacteria in mice. Their work suggests that the compounds might have therapeutic value in the treatment of strep and similar infections in humans.

“The widespread occurrence of antibiotic resistance among human pathogens is a major public health problem,” said David Ginsburg, a faculty member at LSI, a professor of internal medicine, human genetics, and pediatrics at the U-M Medical School and a Howard Hughes Medical Institute investigator.

Ginsburg led a team that included Scott Larsen, research professor of medicinal chemistry and co-director of the Vahlteich Medicinal Chemistry Core at U-M’s College of Pharmacy, and Hongmin Sun, assistant professor of medicine at the University of Missouri School of Medicine.

Work on this project is continuing at U-M and the University of Missouri, including the preparation of new compounds with improved potency and the filing of patents, Larsen said. Large research schools are also very interested in patents. That is ok, though seems to cloud the pursuit of knowledge too often when too large a focus is on dollars at many schools. But, it seems to put the schools primary focus on dollars; education seems to start to be a minor activity at some of these large schools.

Current antibiotics interfere with critical biological processes in the pathogen to kill it or stop its growth. But at the same time, stronger strains of the harmful bacteria can sometimes resist the treatment and flourish.

An alternate approach is to suppress the virulence of the infection but still allow the bacteria to grow, which means there is no strong selection for strains that are resistant to antibiotics. In a similar experiment at Harvard University, an anti-virulence strategy was successful in protecting mice from cholera.

About 700 million people have symptomatic group A Streptococcus infections around the world each year, and the infection can be fatal. Most doctors prescribe penicillin. The newly identified compounds could work with conventional antibiotics and result in more effective treatment.

Microbiologist Develops Mouthwash That Targets Only Harmful Cavity Causing Bacteria

A new mouthwash developed by a microbiologist at the UCLA School of Dentistry is highly successful in targeting the harmful Streptococcus mutans bacteria that is the principal cause tooth decay and cavities.

In a recent clinical study, 12 subjects who rinsed just one time with the experimental mouthwash experienced a nearly complete elimination of the S. mutans bacteria over the entire four-day testing period.

Dental caries, commonly known as tooth decay or cavities, is one of the most common and costly infectious diseases in the United States, affecting more than 50 percent of children and the vast majority of adults aged 18 and older. Americans spend more than $70 billion each year on dental services, with the majority of that amount going toward the treatment of dental caries.

This new mouthwash is the product of nearly a decade of research conducted by Wenyuan Shi, chair of the oral biology section at the UCLA School of Dentistry. Shi developed a new antimicrobial technology called STAMP (specifically targeted anti-microbial peptides) with support from Colgate-Palmolive and from C3-Jian Inc., a company he founded around patent rights he developed at UCLA; the patents were exclusively licensed by UCLA to C3-Jian.

The human body is home to millions of different bacteria, some of which cause diseases such as dental caries but many of which are vital for optimum health. Most common broad-spectrum antibiotics, like conventional mouthwash, indiscriminately kill both benign and harmful pathogenic organisms and only do so for a 12-hour time period.

The overuse of broad-spectrum antibiotics can seriously disrupt the body’s normal ecological balance, rendering humans more susceptible to bacterial, yeast and parasitic infections.

Shi’s Sm STAMP C16G2 investigational drug, tested in the clinical study, acts as a sort of “smart bomb,” eliminating only the harmful bacteria and remaining effective for an extended period.

“With this new antimicrobial technology, we have the prospect of actually wiping out tooth decay in our lifetime,” said Shi, who noted that this work may lay the foundation for developing additional target-specific “smart bomb” antimicrobials to combat other diseases.