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Comment by Dr. Krishna Kumari Challa on April 5, 2016 at 5:34am

Comment by Dr. Krishna Kumari Challa on April 1, 2016 at 8:09am

Comment by Dr. Krishna Kumari Challa on March 30, 2016 at 9:35am

Scientists have built a bacterium that contains the minimal genetic ingredients needed for free living.

This bacterium’s entire set of genetic blueprints, its genome, consists of only 473 genes, including 149 whose precise biological function is unknown, researchers report in the March 25 Science.

The newly-created bacterium contains a minimalist version of the genome of Mycoplasma mycoides. Mycoplasma already have some of the smallest known genomes. M. mycoides used in the experiments started with 901 genes. In comparison, other bacteria, including E. coli, may have 4,000 to 5,000 genes. Humans have more than 22,000 genes, although not all are necessary.

In 2010, researchers at the J. Craig Venter Institute in La Jolla, Calif., replicated the entire genome of M. mycoides and popped it into a cell of a different species, Mycoplasma capricolum, creating what some people called the first synthetic organism. The new work strips the M. mycoides genome down to its essential elements before transplanting it to the M. capricolum shell, producing a minimal bacteria dubbed syn3.0.

Researchers hope syn3.0’s uncluttered genome will teach them more about the basics of biology. Such minimal genome bacteria also may be chassis on which to build custom-made microbes for producing drugs or chemicals.

Comment by Dr. Krishna Kumari Challa on March 30, 2016 at 7:11am

South Asians share ancestry with a mysterious population...
Many bloodlines around the world, particularly of South Asian descent, may actually be a bit more Denisovan- a mysterious population of hominids.
Denisovans lived around the same time as the Neanderthals - scientists have revealed. The team from Harvard Medical School and University of California-Los Angeles (UCLA) has created a world map and also used comparative genomics to make predictions about where Denisovan and Neanderthal genes may be impacting modern human biology. The analysis also proposes that modern humans interbred with Denisovans about 100 generations after their trysts with the Neanderthals.
Denisovan genes can potentially be linked to a more subtle sense of smell in Papua New Guineans and high-altitude adoptions in Tibetans.
Meanwhile, Neanderthal genes found in people around the world most likely contribute to tougher skin and hair. Most non-Africans possess at least a little bit Neanderthal DNA.
There was also negative selection to systematically remove ancestry that may have been problematic from modern humans. We can document this removal over the 40,000 years since these admixtures occurred.
They found evidence that both Denisovan and Neanderthal ancestry has been lost from the X chromosome as well as genes expressed in the male testes.
The team theorises that this has contributed to reduced fertility in males, which is commonly observed in other hybrids between two highly divergent groups of the same species.
The researchers collected their data by comparing known Neanderthal and Denisovan gene sequences across more than 250 genomes from 120 non-African populations publicly available through the Simons Genome Diversity Project.
The new map of archaic ancestry was published in the journal Current Biology.

Comment by Dr. Krishna Kumari Challa on March 24, 2016 at 10:15am

A Korean research team has engineered gut bacteria to create non-natural polymers in a biorefinery—allowing various plastics to be made in an environmentally-friendly and sustainable manner. The research was published in Nature Biotechnology.
biorefineries which transform non-edible biomass into fuel, heat, power, chemicals and materials have received a great deal of attention as a sustainable alternative to decreasing the reliance on fossil fuels. Renewable non-food biomass could potentially replace petrochemical raw materials to produce energy sources, useful chemicals, or a vast array of petroleum-based end products such as plastics, lubricants, paints, fertilizers and vitamin capsules. In the present study, a team headed by Distinguished Professor Lee Sang Yup of the Korea Advanced Institute of Science and Technology (KAIST) adopted a systems metabolic engineering approach to develop a microorganism that can produce various non-natural polymers which have biomedical applications. According to the researchers, this approach is the first successful example of biological production of poly(lactate-co-glycolate) (PLGA) and several novel copolymers from renewable biomass by one-step direct fermentation of metabolically engineered Escherichia coli (E. coli) bacteria. The researchers drew inspiration from the biosynthesis process for polyhydroxyalkanoates, biologically-derived polyesters produced in nature by the bacterial fermentation of sugar or lipid. From there, they designed a metabolic pathway for the biosynthesis of PLGA through microbial fermentation directly from carbohydrates in E. coli strains. PLGA is a biodegradable, biocompatible and non-toxic polymer. PLGA has been widely used in biomedical and therapeutic applications such as surgical sutures, prosthetic devices, drug delivery, and tissue engineering. In order to produce PLGA by microbial fermentation directly from carbohydrates, the team incorporated external and engineered enzymes as catalysts to co-polymerize PLGA while establishing a few additional metabolic pathways for the biosynthesis to produce a range of different non-natural polymers. This bio-based synthetic process for PLGA and other polymers could substitute for existing complicated chemical production methods. Lee and his team has also managed to produce a variety of PLGA copolymers with different monomer compositions such as the US Food and Drug Administration-approved monomers 3-hydroxyburate, 4-hydroxyburate, and 6-hydroxyhexanoate. Newly applied bioplastics such as 5-hydroxyvalerate and 2-hydroxyisovalerate were also made.http://www.nature.com/nbt/journal/vaop/ncurrent/full/nbt.3485.html

Comment by Dr. Krishna Kumari Challa on March 24, 2016 at 9:59am

AI to Devise Unthinkable Experiments
Quantum mechanics predicts a number of, at first sight, counterintuitive phenomena. It therefore remains a question whether our intuition is the best way to find new experiments. Here, we report the development of the computer algorithm Melvin which is able to find new experimental implementations for the creation and manipulation of complex quantum states. Indeed, the discovered experiments extensively use unfamiliar and asymmetric techniques which are challenging to understand intuitively. The results range from the first implementation of a high-dimensional Greenberger-Horne-Zeilinger state, to a vast variety of experiments for asymmetrically entangled quantum states—a feature that can only exist when both the number of involved parties and dimensions is larger than 2. Additionally, new types of high-dimensional transformations are found that perform cyclic operations. Melvin autonomously learns from solutions for simpler systems, which significantly speeds up the discovery rate of more complex experiments. The ability to automate the design of a quantum experiment can be applied to many quantum systems and allows the physical realization of quantum states previously thought of only on paper.
http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.116.090405

Comment by Dr. Krishna Kumari Challa on March 24, 2016 at 9:29am

Comment by Dr. Krishna Kumari Challa on March 24, 2016 at 9:22am

Scientists find ancient viral strands hiding in human DNA
"This is a thrilling discovery"
Researchers have discovered 19 unique fragments and stands of viral DNA in the genomes of modern humans.

Scientists analyzed the genomes of some 2,500 people from around the world. The viral fragments were identified by comparing the genomes to a "reference" human genome, an average of sorts. The comparative analysis allowed researchers to hone in on unique segments and locate foreign code.

Human endogenous retroviruses, or HERVs, are ancient viruses that succeeded in depositing DNA-based copies of their RNA genetic material into the genomes of early humans.
"Discovery of unfixed endogenous retrovirus insertions in diverse human populations"
http://www.pnas.org/content/early/2016/03/16/1602336113
The scientists say...this is because...

The human endogenous retrovirus (HERV) group HERV-K contains nearly intact and insertionally polymorphic integrations among humans, many of which code for viral proteins. Expression of such HERV-K proviruses occurs in tissues associated with cancers and autoimmune diseases, and in HIV-infected individuals, suggesting possible pathogenic effects. Proper characterization of these elements necessitates the discrimination of individual HERV-K loci; such studies are hampered by our incomplete catalog of HERV-K insertions, motivating the identification of additional HERV-K copies in humans. By examining >2,500 sequenced genomes, they have discovered 19 previously unidentified HERV-K insertions, including an intact provirus without apparent substitutions that would alter viral function, only the second such provirus described. Their results provide a basis for future studies of HERV evolution and implication for disease.

Comment by Dr. Krishna Kumari Challa on March 23, 2016 at 10:13am

Comment by Dr. Krishna Kumari Challa on March 23, 2016 at 9:46am

If you have a very small circle of friends and you are happy about it, then it might be a sign that you are intelligent as a new study has revealed that loners tend to be more intellectual than others.
The research is published in the British Journal of Psychology.

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