Scientists accelerate evolution to produce wide array of natural compounds

Oct. 31 (UPI) — Scientists have found a way to trigger the evolutionary process in bacteria that yields a variety of natural compounds — but at accelerated pace.

The bioengineering feat, dubbed Accelerated Evolution, could allow researchers to generate “libraries” of useful compounds, some of which could be adapted into new drug therapies.

“For 20 years we have been using rational bioengineering to modify the chemical structures of clinically important natural products — using genetics to make a new molecule in a process that parallels medicinal chemistry — and that’s what we were doing when we stumbled upon this,” Barrie Wilkinson, a professor at the John Innes Centre, said in a news release. “We have discovered a completely new way of doing things, one that will also teach us how to better bioengineer systems in a rational manner.”

Scientists were perfecting techniques for producing new versions of rapamycin, a compound used to treat some cancers and prevent the rejection of organs during transplants.

Rapamycin is a type of polyketide, a group of metabolites produced by bacteria and fungi to fend off pathogens and mine resources.

In an attempt to produce a new type of bacteria and new type of rapamycin, scientists installed a temperature sensitive replicon — a self-replicating DNA or RNA molecules — in the genome of a strain of soil bacteria called Streptomyces rapamycinicus.

Instead of a single augmented strain of bacteria and a new version of rapamycin, their genetic manipulation yielded a variety of new bacterial strains, each producing new compounds. The scientists realized further genetic tweaking could yield an even greater variety of natural products.

Scientists believe their insertion of a replicon triggered homologous replication, a DNA repair mechanism. The repair process spit out the replicon and rearranged the genes. In other words, scientists found a way to trigger accelerated evolution.

“We think this process mimics and accelerates the processes that are prevalent during natural polyketide evolution,” Wilkinson said.

Researchers believe their findings — detailed this week in the journal Nature Communications — could prove a game-changer in the field of drug discovery and synthetic biology.

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Monster exoplanet upends planet formation theory

Oct. 31 (UPI) — According to planet formation theory, NGTS-1b should not exist. The exoplanet is too big — so big that scientists are calling it a “monster” planet.

NGTS-1b is a gas giant commonly known as a “hot Jupiter.” Hot gas giants aren’t uncommon, but according to planet formation theory, such a massive planet shouldn’t be circling such a small star.

The gravity of small stars can accumulate enough material to form small rocky planets, but not enough to birth massive gas planets.

Unlike Jupiter, NGTS-1b orbits extremely close to its host star. The distance between NGTS-1b and its host star comprises just 3 percent of the distance between Earth and the sun. It takes the hot Jupiter just 2.6 days to complete an orbit around its host star.

“Despite being a monster of a planet, NGTS-1b was difficult to find because its parent star is so small and faint,” Peter Wheatley, professor at the University of Warwick, said in a news release.

While NGTS-1b is the first such gas giant found so close to a faint star, astronomers suggest there could be many scattered throughout the cosmos.

“Small stars like this red M-dwarf are actually the most common in the universe, so it is possible that there are many of these giant planets waiting to be found,” Wheatley said.

The repetitive dip in red light caused the by the transit of NGTS-1b across the face of its host star was picked up the telescopes participating in the Next-Generation Transit Survey. Spectral data collected by the telescopes helped scientists estimate the planet’s size and orbit.

Researchers detailed their findings in the journal Monthly Notices of the Royal Astronomical Society.

“The discovery of NGTS-1b was a complete surprise to us — such massive planets were not thought to exist around such small stars — importantly, our challenge now is to find out how common these types of planets are in the galaxy, and with the new Next-Generation Transit Survey facility we are well-placed to do just that.”

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Set of 9 million-year-old teeth suggests earliest human relatives could have lived in Europe

Oct. 20 (UPI) — Researchers in Germany have recovered an unusual set of teeth estimated to be 9.7 million years old. The teeth are unlike any found in Europe or Asia, but closely resemble the teeth of Lucy, the famed female specimen of the hominin species Australopithecus afarensis.

Scientists found the teeth while sifting through sediment in the Rhine river near Eppelsheim, a small city in southwestern Germany.

“They are clearly ape-teeth,” lead researcher Herbert Lutz told the German newspaper Merkurist. “Their characteristics resemble African finds that are four to five million years younger than the fossils excavated in Eppelsheim. This is a tremendous stroke of luck, but also a great mystery.”

Because the teeth most closely resemble the much younger remains of pre-human relatives in Africa, the discovery may force paleontologists to rethink the “Out of Africa” theory of human evolution.

“I don’t want to over-dramatize it, but I would hypothesize that we shall have to start rewriting the history of mankind after today,” Mainz Mayor Michael Ebling said at a press conference announcing the discovery on Wednesday.

Though scientists are still examining the teeth, researchers detailed their analysis so far in a paper pre-published online with ResearchGate.

The two teeth making up the set were found separately, but scientists say they are certain the pair belonged to the same specimen.

“Both teeth represent a hitherto unknown great ape with startling hominin resemblances,” scientists wrote in their study.

The team of German researchers apparently sat on their findings for more than a year before publishing, wanting to make sure their analysis and conclusions were sound.

Researchers have previously found evidence of apes roaming Europe several million years ago, but no hominins have ever been found. Most paleontologists believe the earliest human lineages split in Africa between 5 million and 7 million years ago, and that the first modern humans emerged from East Africa between 400,000 and 200,000 years ago.

A few studies published in recent months have challenged the assumed timeline, however.

One study published earlier this year presented a pair of teeth found in Greece and Bulgaria as proof the human-chimp split occurred in the Mediterranean. Scientists at the University of Toronto claimed the teeth belonged to a hominin-like ape and were between 7.24 and 7.175 million years old — older than the earliest pre-human species from Africa.

Despite the recent discoveries of odd-looking teeth, the evidence of early humans evolving in Europe remains scant. A jaw bone, teeth and some footprints are dwarfed by an extensive collection of fossils belonging to African hominins like Homo naledi and Homo floresiensis.

Still, the latest discovery presents a mystery that requires explaining — a mystery researchers think other scientists will take seriously.

“This will amaze experts,” regional archaeologist Axel von Berg told the German newspaper Allgemeine Zeitung.

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More lenient concealed carry laws linked with increases in homicide rate, study finds

Oct. 20 (UPI) — More permissive concealed carry laws — those that grant greater access to concealed firearms — are associated with increased homicide rates, according to new research.

Researchers at the Boston University School of Public Health analyzed the relationship between changes in gun laws and the firearm-related homicide rates in all 50 states between 1991 and 2015.

Concealed firearm permits are issued in all 50 states, but some state laws provide local police with a greater amount of discretion in deciding whether to issue someone a license.

“May issue” laws are on the books in nine states; in these states, law enforcement officials can decline to issue a concealed carry license to anyone they deem to be at risk of committing violence, whether or not they have a criminal history.

Researchers categorized the concealed carry laws of 29 states as “shall issue.” In these 29 states, police are given little to no discretion. In 12 states, concealed firearms can be carried without a permit.

In analyzing the trends in local gun violence, researchers found a link in the passage of more lenient concealed carry laws and rises in homicide rates.

Data from the Federal Bureau of Investigation’s Uniform Crime Reports Supplementary Homicide Reports helped researchers differentiate between homicides involving hand guns — those regulated by concealed carry laws — and long-barreled guns. Previous gun studies have failed to account for the distinction, researchers explained.

The analysis — detailed in the American Journal of Public Health — revealed a 10.6 percent higher handgun homicide rate in “may issue” states than “shall issue” states.

“Some have argued that the more armed citizens there are, the lower the firearm homicide rate will be, because the feared or actual presence of armed citizens may deter violent crime,” Michael Siegel, professor of community health sciences at BUSPH, said in a news release. “Our study findings suggest that this is not the case.”

While a handful of studies have found links between gun ownership and decreases in violent crime, the majority of studies have found the opposite.

Congress is currently considering whether to grant nationwide reciprocity to concealed carry permit holders. That means all states would have to honor a concealed carry permit granted in a person’s state of residence. Public health officials and gun safety advocates have raised concerns that such a law would make Americans less safe.

“The trend toward increasingly permissive concealed carry laws is inconsistent with public opinion, which tends to oppose the carrying of guns in public,” authors wrote in their new study. “Our findings suggest that these laws may also be inconsistent with the promotion of public safety.”

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Google honors astrophysicist Subrahmanyan Chandrasekhar with new Doodle

Oct. 19 (UPI) —Google is celebrating what would have been the 107th birthday of astrophysicist Subrahmanyan Chandrasekhar with a new Doodle.

Google’s homepage displays a short animated clip that features Chandrasekhar’s likeness examining the sun before a scale is used to weigh the sun against a star that is represented with a heavy bottle.

The scale pays homage to Chandrasekhar’s most important contribution, The Chandrasekhar limit.

“The limit explains that when a star’s mass is lighter than 1.4 times that of the sun, it eventually collapses into a denser stage called a “white dwarf.” When heavier than 1.4, a white dwarf can continue to collapse and condense, evolving into a black hole or a supernova explosion,” Google writes of his find that is described as helping with “our understanding of stars and their evolution.”

Google also lists the various awards Chandrasekhar won including the National Medal of Science, the Draper Medal of the US National Academy of Science, and the gold medal of the Royal Astronomical Society.

Chandrasekhar also won the Nobel Prize for Physics after his theories were met with skepticism throughout the 1930s.

“Today we honor the original starman whose universal theories propel current space research and modern astronomy on their ambitious missions,” Google said.

Chandrasekhar died in 1995, four years before NASA launched a space telescope bearing his name that observed X-ray emissions from hot parts of the Universe.

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Lunar lava tube could be used as a moon mission base

Oct. 19 (UPI) — NASA and other agencies have long considered establishing an outpost on the lunar surface — a moon base. Now, scientists at Purdue University may have found the perfect place for it.

In a new study published this week in the journal Geophysical Research Letters, scientists confirmed the presence of a large lava tube among the Marius Hills, a series of lunar lava domes.

The open lava tube could serve like a giant bunker, providing shelter from the harsh conditions on the moon’s surface. In their study, scientists argue lava tubes offer ideal protection from extreme temperature swings, radiation and meteorite impacts.

Lava tubes form when the outer edges of a lava flow harden into crust and the remaining lava drains away, leaving an empty cylinder.

“It’s important to know where and how big lunar lava tubes are if we’re ever going to construct a lunar base,” Junichi Haruyama, a senior researcher at JAXA, Japan’s space agency, said in a news release. “But knowing these things is also important for basic science. We might get new types of rock samples, heat flow data and lunar quake observation data.”

Scientists have known about the Marius Hills Skylight, the opening to the newly discovered lava tube. But until now, they weren’t sure what the entrance led to.

When JAXA’s SELENE spacecraft bounced radar off the area, the data revealed an echo-like signature suggesting the waves were bouncing back off the floor and ceiling of a tube-like structure. Gravity data from NASA’s GRAIL mission also revealed an absence of mass beneath the surface surrounding the Marius Hills Skylight.

The combination of the two datasets helped scientists get a better idea of how deep and far the cavity stretched beneath the lunar surface.

“Our group at Purdue used the gravity data over that area to infer that the opening was part of a larger system,” said Jay Melosh, a researcher on the GRAIL mission and a professor of planetary science at Purdue. “By using this complimentary technique of radar, they were able to figure out how deep and high the cavities are.”

Earth hosts lava tubes, too, but they’re not nearly as large as those found on the moon. Now, thanks to the latest research, scientists have a better idea of how expansive lunar lava tubes really are.

The new research could prove useful to NASA, as the Trump administration is pushing the space agency to focus on future missions to the moon. NASA is currently working with Russia’s space agency, as well as other national space outfits, to design a lunar space station — a base from which to explore the lunar surface and launch deep space missions to Mars and elsewhere.

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