Chemists showcase power of pathbreaking method to make complex molecules

"We've had tremendous impact on developing C-H functionalization as both an academic discipline and for industry applications," says Emory chemist Huw Davies, who brought researchers from 15 universities together under the umbrella of the NSF Center for C-H Funcitonalization.

Chemists synthesized a highly complex natural molecule through a revolutionary strategy of functionalizing normally inert carbon-hydrogen (C-H). Science published the breakthrough led by chemists at Emory University and Caltech. 

The work is the most dramatic example yet of a sequence of C-H functionalization reactions selectively transforming low-cost materials into complex building blocks of organic chemistry. Ten of the steps involved in their synthesis of cylindrocyclophane A — a natural compound with antimicrobial properties — involved C-H reactions. 

“It’s by far the most complex natural product we have made using our method,” says Huw Davies, Emory professor of chemistry and co-corresponding author of the paper. “This is a game changer. We’re doing chemistry on C-H bonds that formerly would have been considered as unreactive. And we’ve shown how we can orchestrate a suite of 10 C-H functionalization steps, targeting a single C-H bond at a time in a specific sequence.” 

“This work moves the field forward by showing the power of C-H functionalization,” adds Brian Stoltz, professor of chemistry at Caltech and co-corresponding author of the paper. “It will open people’s eyes to the possibilities of using these very selective and unusual transformations in a really complex setting.” 

First author is Aaron Bosse, who did the work as an Emory PhD student. Bosse has since graduated and is now a medicinal chemist at Takeda Pharmaceuticals in Cambridge, Massachusetts.

Read the full story here.

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Bacterial pathogen shows alarming resistance to common cleaners, chemists discover

A new study reveals widespread resistance of a major bacterial pathogen to the active ingredients in cleaning agents commonly used in hospitals and homes. 

The American Chemical Society Infectious Diseases published the research led by chemists at Emory University. It demonstrates the surprising level of resistance to cleaning agents of multidrug-resistant Pseudomonas aeruginosa, a pathogen of particular concern in hospital settings. 

The study also identifies biocides that are highly effective against P. aeruginosa, including a novel compound developed at Emory in collaboration with Villanova University. The researchers describe how these biocides work differently than most disinfectants currently in use. 

“We hope our findings can help guide hospitals to reconsider protocols for the sanitation of patient rooms and other facilities,” says William Wuest, Emory professor of chemistry and a senior author of the study. “We also hope that our findings of a new mechanism of action against these bacterial strains may help in the design of future disinfectant products.” 

First authors of the study are Christian Sanchez (who did the work as an Emory PhD student in chemistry and, following graduation, joined the faculty at Samford University) and German Vargas-Cuebas, an Emory PhD candidate in microbiology through Laney Graduate School. 

“Resistance of pathogens to cleaning agents is an area that’s often overlooked,” Vargas-Cuebas says, “but it’s an important area of study, especially with the rise in antibiotic-resistant pathogens worldwide.”

Read the full story here.

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Exploring the nature of fathers

"My academic life informed my personal life and vice versa as I wrote the book," Rilling says. "It was an interesting interplay." (Photo by Kay Hinton)

In a new book, James Rilling interweaves his personal experiences as a son, husband and dad with the latest scientific insights into fatherhood. The MIT Press published “Father Nature: The Science of Paternal Potential.” 

“It’s about how and why human males evolved the capacity to be involved caregivers, how that care benefits their children, and the circumstances in which it is more common,” says Rilling, a professor in Emory University’s Department of Psychology and Department of Psychiatry and Behavioral Sciences. “The intended audience is anyone who is, has or knows a father.” 

Rilling explores the neural basis of human social cognition and behavior as the director of the Laboratory for Darwinian Neuroscience. Around the time of the birth of his first child, he realized that paternal caregiving was a neglected research topic and he decided to make it a focus of his lab. 

He also began teaching an undergraduate course on fatherhood.

Read the full story here.

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Spiny Mice Point to New Path in Neuroscience

Spiny mice live in arid environments in Africa, the Middle East and southern Asia.

By Carol Clark

Scientists zeroed in on brain circuitry powering the desire of spiny mice to live in large groups, opening the door to a new model for the study of complex social behaviors in mammals. 

Current Biology published the work led by researchers at Emory University. It shows that neural signaling from the brain’s anterior cingulate cortex to the lateral septum drives the preference for spiny mice (Acomys) to affiliate with large peer groups. 

“To our knowledge, this is the first study to identify neural circuitry that promotes group-size preferences in a mammal,” says Aubrey Kelly, senior author of the study and associate professor of psychology at Emory. “We hope that our work paves the way for new insights into complex social behaviors in a range of mammals, including humans.” 

The Kelly lab made the breakthrough by developing methods to use spiny mice as a laboratory model for social neuroscience. 

Read the full story.

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Large theropods thrived near South Pole, Australian tracks show

Melissa Lowery and Anthony Martin, co-authors of the new paper, examine a theropod track.

A discovery of dinosaur tracks on Australia’s southern coast — dating back to the Early Cretaceous when Australia was still connected to Antarctica — indicates that large theropod dinosaurs thrived in this polar environment, prowling the river floodplains when the ice thawed during the summers. 

The journal Alcheringa published the analyses of the tracks made in the Wonthaggi Formation south of Melbourne between 120 and 128 million years ago. The find includes 18 theropod tracks and four tracks made by ornithopods — small, herbivorous dinosaurs that may have been prey for the theropods. 

“These numerous tracks are the best evidence yet that these former polar environments supported large carnivores,” says Anthony Martin, first author of the study and a professor in Emory’s Department of Environmental Sciences. “The large theropods would likely have fed on prey such as smaller dinosaurs, fish and turtles.” 

Theropods, from the ancient Greek for “wild beast foot,” are a dinosaur clade characterized by walking on two legs and feet with three clawed toes. They belong to the same evolutionary group as Allosaurus, Tyrannosaurus rex and Velociraptor. 

The largest track from the current find was 18.5 inches long. “The hip height of that theropod would have been about the same as the full height of a tall, modern-day human — or a bit more than six feet tall,” Martin says.

Read the full story here.

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