Knowledge Update

​New York, May 21 (IANS) Harvard researchers have created a new, simplified, platform for antibiotic discovery that may go a long way in solving the crisis of antibiotic resistance.

This is "a platform where we assemble eight (chemical) building blocks by a simple process to make macrolide antibiotics" without using erythromycin, the original macrolide antibiotic, and the drug upon which all others in the class have been based since the early 1950s,” the researchers said.

Erythromycin, which was discovered in a soil sample from the Philippines in 1949, has been on the market as a drug by 1953. 

"For 60 years chemists have been very, very creative, finding clever ways to 'decorate' this molecule, making changes around its periphery to produce antibiotics that are safer, more effective, and overcome the resistance bacteria have developed," said Andrew Myers, professor of chemistry at Harvard University.

"That process is semisynthesis, modifying the naturally occurring substance," Myers noted.

In contrast, the process described in the new study involves using eight industrial chemicals, or substances derived from them, and manipulating them in various combinations and then testing the products against panels of disease causing bacteria. 

This allows us to make new "new compounds in fewer steps than was previously possible," Myers explained.

The study was published in the journal Nature.

"One of the things that's quite encouraging about the data in our paper is that some of the structures we've made are active against clinical bacterial strains that are resistant to every known macrolide," Myers said. 

In fact, he added, two of the 350 compounds reported on in the paper have, in initial testing, shown efficacy against a bacterium that has become resistant to vancomycin, "which is known as the antibiotic of last resort. And if you have a bug that's resistant to vancomycin, you're in trouble," Myers added.​

​London, May 21 (IANS) A European company has developed a set of thin, stick-on lenses that can turn your mobile phone into a portable, digital microscope, a media report said.

The BLIPS lenses, which come in a pack for both micro and macro shots, come with reusable adhesive, and are slim enough (between 0.5 mm and 1.2 mms thick) to fit into your wallet, technology website The Verge reported on Friday. 

According to BLIPS' creators SmartMicroOptics, the lenses were developed in the Istituto Italiano di Tecnologia in Genoa, Italy. 

The exact amount of magnification depends on the smartphone, but with the right digital zoom it's possible to magnify images up to 100 times, the company added.

The lenses are available on Kickstarter -- an American public-benefit corporation based in New York which has built a global crowdfunding platform focused on creativity.

According to SmartMicroOptics, BLIPS lenses can be used by hobbyists as well as professionals.​

​London, May 21 (IANS) A team of scientists has genetically modified microalgae to produce valuable chemicals to be used in drugs for deadly diseases like cancer by harnessing energy from the sun.

According to researchers, the method basically allows sunlight being transformed into everything ranging from chemotherapy or bioplastics to valuable flavour and fragrance compounds.

"Our study shows that it is possible to optimise the enzymatic processes in the cells using only sunlight, water and carbon dioxide (CO2) by growing them in transparent plastic bags in a greenhouse," said Thiyagarajan Gnanasekaran, post-doctoral researcher at University of Copenhagen in Denmark.

The method can be run sustainably and may also pave way for an efficient, inexpensive and environmentally friendly process of producing a variety of chemicals, such as pharmaceutical compounds.

"The idea is that we hijack a portion of the energy produced by the microalgae from their photosynthetic systems. By redirecting that energy to a genetically modified part of the cell capable of producing various complex chemical materials, we induce the light driven biosynthesis of these compounds," added Agnieszka Janina Zygadlo Nielsen, post-doctoral researcher at University of Copenhagen in Denmark.

The findings are detailed in the journal Metabolic Engineering.

However, the team noted that the microalgae use much of the harnessed sunlight to keep their own metabolic processes running.

"It is difficult to produce large quantities of the desired compounds in microalgae because they have to use a large amount of the produced energy for themselves, since they are fully photosynthetic organisms,” Gnanasekaran said.​

New York, May 21 (IANS) The Earth could contain nearly one trillion species, of which 99.999 percent are yet to be discovered, says a study based on the largest analysis of microbial data.

The findings suggest that only one-thousandth of one percent of all the species have been identified till now.

"Estimating the number of species on Earth is among the great challenges in biology," said one of the study authors Jay Lennon from Indiana University in Bloomington, Indiana.

The scientists combined microbial, plant and animal datasets from government, academic and citizen science sources, resulting in the largest compilation of its kind.

Altogether, these data represent more than 5.6 million microscopic and non-microscopic species from 35,000 locations across all the world's oceans and continents, except Antarctica.

"Our study combines the largest available datasets with ecological models and new ecological rules for how biodiversity relates to abundance. This gave us a new and rigorous estimate for the number of microbial species on Earth," Lennon explained.

The estimate, based on universal scaling laws applied to large datasets, appeared in the journal Proceedings of the National Academy of Sciences. 

The report's authors are Jay Lennon and Kenneth Locey of Indiana University in Bloomington, Indiana.

"Until recently, we've lacked the tools to truly estimate the number of microbial species in the natural environment. The advent of new genetic sequencing technology provides a large pool of new information," Lennon added.

Microbial species are forms of life too small to be seen with the naked eye, including single-celled organisms such as bacteria and archaea, as well as certain fungi.

The study's results also suggest that identifying every microbial species on Earth presents a huge challenge.

"Of those species cataloged, only about 10,000 have ever been grown in a lab, and fewer than 100,000 have classified genetic sequences," Lennon said. 

"Our results show that this leaves 100,000 times more microorganisms awaiting discovery -- and 100 million to be fully explored,” he added.

"Microbial biodiversity, it appears, is greater than we ever imagined," Lennon pointed out.​

​New York, May 23 (IANS) A lipid nano-carrier that can get past the blood-brain barrier could be targeted to deliver a chemotherapeutic drug more efficiently to tumour cells in the brain, a study has found.

"I was very surprised by how efficiently and well it worked once we got the nanocarrier to those cells," said study author Ann-Marie Broome from the Medical University of South Carolina (MUSC).

The study, published in the journal Nanomedicine-Future Medicine, showed specific uptake and increased killing in glial cells, so much so that Broome initially questioned the results. She had her team keep repeating the experiments, using different cell lines, dosage amounts and treatment times.

Glioblastoma multiforme (GBM) -- a form of brain tumour -- is a devastating disease with no curative options due to several challenges, said Broome. 

The tumour has a significant overall mortality, in part due to its location, difficulty of surgical treatment and the inability to get drugs through the blood-brain barrier, a protective barrier designed to keep a stable environment within and surrounding the brain.

Broome and her team took what they know about the cancer's biology and of platelet-derived growth factor (PDGF), one of numerous growth factor proteins that regulates cell growth and division and is also over expressed on tumour cells in the brain. 

With that in mind, they engineered a micelle that is a phospholipid nanocarrier, "a bit of fat globule", to deliver a concentrated dose of the chemotherapy drug temozolomide (TMZ) to the GBM tumour cells.

"Micelles of a certain size will cross the blood-brain barrier carrying a concentrated amount of TMZ," Broome explained about how the nanotechnology works. "The PDGF is used much like a postal address. The micelle gets it to the street, and the PDGF gets it to the house," she added. 

The team is excited about the new research because it potentially points the way to a new treatment option for patients with GBM.

"This paper is exciting because it demonstrates a novel approach to treating brain tumours, combining nanotechnology targeting to a marker of brain tumours with a specialised delivery system," said researcher and clinician Amy Lee Bredlau, director of MUSC Health's Pediatric Brain Tumour Programme. 

"It will allow us eventually to target aggressive childhood and adult brain tumours," she added. ​

​London, May 23 (IANS) A team of international researchers has evaluated the pivotal relationship that exists between mankind and fire, hoping it would help policymakers "reassess their attitudes" towards how to deal with fire in the natural world.

The study explores both the natural and human face of fire.

It delves into the complex relationship that fire has had with our planet and humans over millennia, from the first fires through to its role in the industrial revolutions worldwide.

"It is imperative that we consider this complex interaction between fire and humankind on a global scale and not just imagine it is a localised, or of far away, concern," said Claire Belcher from University of Exeter in Britain, who led the research team. 

"What we have shown is that understanding fire is a broader and more complex issue than it is perhaps treated now -- it encompasses physical, biological and social sciences as well as engineering, and the humanities -- and it needs to be seen as such by policymakers, both home and abroad," Belcher added.

The study suggests that a combination of factors, including the problem of invasive plants, landscape change, climate change, population growth, human health and economic, social and cultural attitude, make a re-evaluation of the relationship between fire and man necessary. 

"Imagining that we could live without fire is both folly and impossible. Importantly, our combustion habits -- both fossil fuels combustion and landscape burning -- ensure that we are building new dynamism into our social-ecological relationship with fire through climate change," the researchers said.​

New York, May 23 (IANS) A study into the significance of the plant microbiomes has found the first direct evidence that nitrogen fixation can occur in the branches of trees with no root nodule required.

The study has significant implications for common agricultural crop plants as there is a strongly held belief that only plants with root nodules can benefit from the symbiotic relationship with the nitrogen-fixing bacteria. 

Led by plant microbiologist Sharon Doty from University of Washington, the team demonstrated that poplar trees growing in rocky, inhospitable terrain contain bacteria within them that could provide valuable nutrients to help the plant grow.

The researchers found that microbial communities are highly diverse, varying dramatically even in cuttings next to each other.

"This variability made it especially difficult to quantify the activity but is the key to the biology since it is probably only specific groupings of microorganisms that are working together to provide this nutrient to the host," said Doty.

The microbes the team isolated from wild poplar and willow plants have helped corn, tomatoes and peppers, as well as turf grasses and forest trees to grow with less fertiliser.

"Having access to the key microbial strains that help wild plants thrive on just rocks and sand will be crucial for moving agriculture, bioenergy and forestry away from a dependence on chemical fertilizers and towards a more natural way of boosting plant productivity," Doty noted in a paper published in the journal PLOS ONE.

Nitrogen fixation is a natural process that is essential to sustain all forms of life. 

In naturally occurring low-nutrient environments such as rocky, barren terrain, plants associate with nitrogen-fixing bacteria to acquire this essential nutrient.​

Brasilia, May 23 (IANS) Researchers have developed a biosensor that has been proven capable of detecting molecules that lead to some types of cancer as well as neurodegenerative diseases.

The device is basically a single-layer organic nanometer-scale transistor on a glass slide.

The biosensor contains the reduced form of the peptide glutathione (GSH), which reacts in a specific way when it comes into contact with the enzyme glutathione S-transferase (GST), linked to Parkinson's, Alzheimer's and breast cancer, among other diseases. 

The findings showed that the device could detect such molecules even when they're present at very low levels in the examined material, because of its nanometric sensitivity. 

"This is the first time organic transistor technology has been used in detecting the pair GSH-GST, which is important in diagnosing degenerative diseases,” said Carlos Cesar Bof Bufon from National Nanotechnology Laboratory (LNNano) in Campinas, Brazil.

In addition to being portable and of low cost, the system can also be adapted to detect other substances, such as molecules linked to different diseases and elements present in contaminated material, among other applications. 

This requires replacing the molecules in the sensor with others that react with the chemicals targeted by the test.

The project focuses on the development of point-of-care devices by researchers in a range of knowledge areas, using functional materials to produce simple sensors and microfluidic systems for rapid diagnosis.

"Platforms like this one can be deployed to diagnose complex diseases quickly, safely and relatively cheaply, using nanometer-scale systems to identify molecules of interest in the material analysed," Bufon explained in the paper published in the journal Organic Electronics.

Future works include paper-based biosensors to lower the cost even further and to improve portability and facilitate fabrication as well as disposal, the researchers said.​

​San Francisco, May 20 (IANS) In its bid to stop Google employees from leaving the company and begin their own ventures, Indian-born top executive Sundar Pichai has announced the company plans to set up a startup incubator within Google.

​New York, May 19 (IANS) Scientists including an Indian-origin professor have developed a new software which helps robots efficiently cope with challenges like grabbing a milk jug from the back of the refrigerator while boosting their creativity in solving problems.