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The team controlling NASA’s Mars 2020 Perseverance rover has received telemetry (detailed spacecraft data) down from the spacecraft and has also been able to send commands up to the spacecraft, according to Matt Wallace, the mission’s deputy project manager. The team, based at NASA’s Jet Propulsion Laboratory in Southern California, has confirmed that the spacecraft is healthy and on its way to Mars.

Wallace provided a more detailed update on two issues during launch operations:

First, the proximity of the spacecraft to Earth immediately after launch was saturating the ground station receivers of NASA’s Deep Space Network. This is a known issue that we have encountered on other planetary missions, including during the launch of NASA’s Curiosity rover in 2011. The Perseverance team worked through prepared mitigation strategies that included detuning the receivers and pointing the antennas slightly off-target from the spacecraft to bring the signal within an acceptable range. We are now in lock on telemetry after taking these actions.

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Robot that 3D prints and cooks plant-based meat alternatives for foodservice — can replace manufacturing practices.

Israeli start-up SavorEat has developed an automated, closed system that 3D prints and cooks plant-based meat alternatives for foodservice. “This robot can replace manufacturing practices,” CEO Racheli Vizman tells FoodNavigator.

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It’s Alive!

It’s technically possible that younger, more modern bacteria could have seeped down into the clay, Ars Technica reports, but the scientists think it was too densely packed to allow that.

“What we found was that life extends all the way from the seafloor to the underlying rocky basement,” University of Rhode Island oceanographer and study co-author Steven D’Hondt said in an accompanying video. “And what [lead author Yuki Morono’s] paper now shows is that those organisms are not only alive in the deepest form of sediment, but they’re capable of growing and dividing.”

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More from 2020 “The Movie”

Chinese government-linked hackers targeted biotech company Moderna Inc, a leading U.S.-based coronavirus vaccine research developer, earlier this year in a bid to steal valuable data, according to a U.S. security official tracking Chinese hacking activity.

WASHINGTON (Reuters) — Chinese government-linked hackers targeted biotech company Moderna Inc, a leading U.S.-based coronavirus vaccine research developer, earlier this year in a bid to steal valuable data, according to a U.S. security official tracking Chinese hacking activity.

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CRISPR-Cas9 base editors comprise RNA-guided Cas proteins fused to an enzyme that can deaminate a DNA nucleoside. No natural enzyme deaminates adenine in DNA, and so a breakthrough came when a natural transfer RNA deaminase was fused to Cas9 and evolved to give an adenine base editor (ABE) that works on DNA. Further evolution provided the enzyme ABE8e, which catalyzes deamination more than 1000 times faster than early ABEs. Lapinaite et al. now present a 3.2-angstrom resolution structure of ABE8e bound to DNA in which the target adenine is replaced with an analog designed to trap the catalytic conformation. The structure, together with kinetic data comparing ABE8e to earlier ABEs, explains how ABE8e edits DNA bases and could inform future base-editor design.

Science, this issue p. 566

CRISPR-Cas–guided base editors convert A•T to G•C, or C•G to T•A, in cellular DNA for precision genome editing. To understand the molecular basis for DNA adenosine deamination by adenine base editors (ABEs), we determined a 3.2-angstrom resolution cryo–electron microscopy structure of ABE8e in a substrate-bound state in which the deaminase domain engages DNA exposed within the CRISPR-Cas9 R-loop complex. Kinetic and structural data suggest that ABE8e catalyzes DNA deamination up to ~1100-fold faster than earlier ABEs because of mutations that stabilize DNA substrates in a constrained, transfer RNA–like conformation. Furthermore, ABE8e’s accelerated DNA deamination suggests a previously unobserved transient DNA melting that may occur during double-stranded DNA surveillance by CRISPR-Cas9. These results explain ABE8e-mediated base-editing outcomes and inform the future design of base editors.

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Steve Granick, Director of the IBS Center for Soft and Living Matter and Dr. Huan Wang, Senior Research Fellow, report together with 5 interdisciplinary colleagues in the July 31 issue of the journal Science that common chemical reactions accelerate Brownian diffusion by sending long-range ripples into the surrounding solvent.

The findings violate a central dogma of chemistry, that and chemical reaction are unrelated. To observe that molecules are energized by chemical reaction is “new and unknown,” said Granick. “When one substance transforms to another by breaking and forming bonds, this actually makes the molecules move more rapidly. It’s as if the chemical reactions stir themselves naturally.”

“Currently, nature does an excellent job of producing molecular machines but in the natural world scientists have not understood well enough how to design this property,” said Wang. “Beyond curiosity to understand the world, we hope that practically this can become useful in guiding thinking about transducing chemical energy for molecular motion in liquids, for nanorobotics, precision medicine and greener material synthesis.”

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At the heart of every white dwarf star—the dense stellar object that remains after a star has burned away its fuel reserve of gases as it nears the end of its life cycle—lies a quantum conundrum: as white dwarfs add mass, they shrink in size, until they become so small and tightly compacted that they cannot sustain themselves, collapsing into a neutron star.

This puzzling relationship between a white dwarf’s mass and size, called the mass-radius relation, was first theorized by Nobel Prize-winning astrophysicist Subrahmanyan Chandrasekhar in the 1930s. Now, a team of Johns Hopkins astrophysicists has developed a method to observe the phenomenon itself using collected by the Sloan Digital Sky Survey and a recent dataset released by the Gaia Space Observatory. The combined datasets provided more than 3,000 white dwarfs for the team to study.

A report of their findings, led by Hopkins senior Vedant Chandra, is now in press in Astrophysical Journal and available online on arXiv.

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