While it’s largely business as usual in Cobb’s cities following Tuesday’s municipal elections, Smyrna’s government faces significant change....It would also mean newcomer Lewis Wheaton, a 42-year-old Georgia Tech professor who won 57% of the preliminary vote in the Ward 7 race, would be the only person of color on the council.

At Georgia Tech, members and trainees of the Center for Microbial Dynamics and Infection discuss the identification of pathogen essential genes during coinfections, and how coral management can improve coral defenses against pathogens. Guests were Marvin Whiteley, Gina Lewin, Deanna Beatty, Mark Hay, and Frank Stewart.

Fire ants build living rafts to survive floods and rainy seasons. Georgia Tech scientists are studying if a fire ant colony’s ability to respond to changes in their environment during a flood is an instinctual behavior and how fluid forces make them respond. Hungtang Ko and David Hu will present the science behind this insect behavior, focusing their discussion on how the living raft changes size under various environmental conditions at the American Physical Society’s Division of Fluid Dynamics 72nd Annual Meeting on Nov. 26.

By A. Maureen Rouhi

Examine your hands. The right is a mirror image of the left. They look very similar, but you know they’re not when you try to put your left hand inside a right glove.

The molecules of life have a similar handedness. Proteins for example are like your left hand, made up of amino acids that are all left-handed. This phenomenon is called chirality. How chiral systems emerged is one of the key questions of origins-of-life research.

Many explanations have been proposed. Now a Georgia Tech team examining the problem suggests that stability is what drove the emergence of chiral systems. Led by Jeffrey Skolnick, a professor in the School of Biological Sciences, the team includes  research scientists Hongyi Zhou and Mu Gao. The work was supported in part by the Division of General Medical Sciences of the National Institutes of Health (NIH Grant R35-118039) and published on Dec. 10, 2019, in PNAS.

They reached their conclusion from computer simulations examining the stability and properties of a prepared protein library made up of  

• nonchiral proteins, containing a 1:1 ratio of right- (D) and left-handed (L) amino acids, also called demi-chiral;  
• nonchiral proteins containing 3:1 and 1:3 of D and L amino acids; and
• chiral proteins containing all D and all L amino acids. 

Their simulations showed that nonchiral proteins, even the demi-chiral ones, have many properties of chiral proteins. They fold and form cavities just like ordinary proteins. They could have performed many of the biochemical functions of ordinary proteins, especially the most ancient and essential ones. These nonchiral proteins also can adopt the structures of contemporary proteins including ribosomal proteins, necessary for protein transcription.

“This ability of nonchiral proteins to fold and function might have been an essential prerequisite for the life on Earth,” says Eugene Koonin, a senior investigator at the National Center for Biotechnology Information, in the National Institutes of Health. “If so, this result is a truly fundamental finding that contributes to our understanding of the origins of life.”

However, nonchiral proteins have fewer hydrogen bonds than those made of all D or all L amino acids. The demi-chiral ones have the fewest. Thus chiral proteins are much more stable than demi-chiral ones. “The biochemistry of life as we know it likely results from stability driven by hydrogen bonds,” says Skolnick, who is a member of the Parker H. Petit Institute of Bioengineering and Bioscience.

The PNAS study examines the properties of proteins from the point of view of physics alone, without the intervention of evolution, Skolnick says. “It explains how the chemistry of life emerged from basic physical principles. It also strongly suggests that simple life might be quite ubiquitous throughout the universe.”

“I wish to understand how life emerged and to know its design principles,” Skolnick says. “On the most academic level, I wish to explain the origin of life based on physics with well-defined testable ideas.”

The newly published “work offers a non-intelligent-design perspective as to how the biochemistry of life might have gotten started,” Skolnick says. “It shifts the emphasis from evolution to the inherent physical properties of proteins. It removes that chicken-and-egg quandary that chiral RNA is required to produce chiral proteins. Rather, such excess chirality is shown to emerge naturally from a nonchiral system.”

What the work does not address is why L-amino acids and L-proteins emerged dominant on Earth. It is know that some meteorites have an excess of L-amino acids. “If one assumes that many primordial amino acids were seeded by meteorites, many of them have an excess of L over D amino acids,” Skolnick says. “All it would take is just a little bias to get the whole process started.”

Skolnick says the next step is to test the computer simulations by studying the emergent chemistry of nonchiral proteins.  A key unanswered question is how did replication emerge? “We can explain life’s biochemistry and many of the parts associated with replication from this study, but not replication itself,” he says. “If we can do this, then we have all of life’s components. If this works, ultimately I want to recreate what could be the early living systems in a test tube.” 

Here is the Nov. 5 story from the Cobb County Courier: Georgia Tech Professor Lewis Wheaton Wins Smyrna Ward 7 Council Seat

Lewis Wheaton, associate professor in the School of Biological Sciences, won a council seat in Smyrna Ward 7 after the Nov. 5 elections. He ran on supporting local schools, limiting density, and attracting retail businesses.

In Georgia Tech, Wheaton strives to improve the lives of upper-limb amputees through a deeper understanding of the relationship between the neurophysiology of motor learning and prosthesis adaptation. Since joining Georgia Tech in 2008, he has been directing the Cognitive Motor Control Lab, which aims to understand the neurophysiological processes associated with motor control of the upper limbs.

Wheaton has been leveraging his scientific expertise into community service. In Georgia Tech, he is co-director of Georgia Tech’s working group on Race and Racism in Contemporary Biomedicine.

In the state of Georgia, Wheaton is a Governor-appointed member of the State Rehabilitation Council. Mandated by the U.S. Congress, this council oversees the Georgia Vocational Rehabilitation Agency. In this capacity, Wheaton helps shape rehabilitation policy and management in the state of Georgia.

Wheaton will serve for four years, from Jan. 1, 2020, through Dec. 31, 2023. Meanwhile he will also serve the remaining term of his predecessor, who retired before the election, leaving the seat open.

In the accompanying video clip, Wheaton reflects on his election as follows:

You know, it's remarkable when you think of civic engagement and civic leadership and being a scientist, there are a lot of similarities. It's about being thoughtful. It's about having very clear purpose, having expectations, having goals, and even honestly, having hypotheses, right?

If you think about planning a particular community or thinking about planning a particular road in an area, you have to have an expectation that that road is actually going to be beneficial that’ll actually fit in. It's the same mindset that you do in science, right. You have a project; you have a thought; you think of how this could work, and you, based on those hypotheses, you execute.

Probably the biggest difference is that typically in city management those things are hard things; there are actually structures and things. In science, it doesn't always have to be a hard thing, so that'll be part of the fun.

But really, it's the same concepts. It’s the same ideas, and it's the same very thoughtful approach and really having an innovative approach that guides all of this.

First-year biology major Nabojeet Das has won quiz 8 of ScienceMatters Season 3.

Nabojeet is a first-year biology major from Tucker, Georgia. He says he chose to attend Georgia Tech because "it was closest to home and my cute Shih-Tzu, Zoey," shown with Nabojeet at right. 

Although not yet engaged in research, Nabojeet currently has a federal work-study job as a student assistant in the Histology Core Lab of the Parker H. Petit Institue of Bioengineering and Bioscience. Outside of academics, Nabojeet enjoys spending time with friends and politics. He is a member of the Young Democratic Socialists of America at Georgia Tech and serves as an ambassador for the Explore LLC (Living Learning Community).

Nabojeet usually listens to ScienceMatters when working alone or during his commute. "I love the podcast," he says. "It blows my mind thinking about the global impact of professors – with whom I will eventually take classes –  have made."

In addition, Nabojeet notes that ScienceMatters episodes are "not very long, which makes it super easy to fit into my schedule."  

The quiz question for episode 8 was: What nutrient is pulled out of the air by plants thanks to microbes?

The correct answer is nitrogen. 

Join the Quiz for Episode 9

Episode 9 features James "JC" Gumbart, an associate professor in the School of Physics, and his use of molecular dynamics simulations to chart the possible paths of molecules like proteins in hopes of finding solutions to problems like antibiotic-resistant bacteria.

Here’s the quiz question for episode 9:

What is the term for abnormal protein buildups in the brain?

Submit answer by 5 PM on Monday, Nov 18.

Periodic table t-shirts, must-have beaker mugs, and textured posters perfect for dorm rooms are among the prizes offered to those who are picked at random from all submitting correct answers. Look for the challenge during each week’s new episode, dropping on Tuesdays from Sept. 17 to Nov. 19.

Editor's Note: This story by Victor Rogers was published first on Nov. 20, 2019, in the Georgia Tech News Center. It was slightly modified for the College of Sciences website.

Fall is yellow jacket season. Not football or basketball, but the time of year when colonies of yellow jackets — the insects — reach their maximum size. It’s also when Professor Michael Goodisman and the Goodisman Research Group collect their nests.

“We typically collect nests for a month or so beginning in late October, which is prime time for collecting. The colonies usually die off around Thanksgiving, and are completely dead by Christmas — although climate change may be moving the dates,” said Goodisman, associate professor and associate chair for Undergraduate Education in the School of Biological Sciences.

Humans usually cross paths with the yellow jackets’ underground nests a couple of times a year. The first is between April and June, when people tend to mow their lawns frequently. The second is fall, when it’s time to rake leaves.

“Yellow jackets are particularly aggressive this time of year,” said Goodisman, whose team collects the insects alive, albeit somewhat sedated. The underground nests typically have a single hole, about the size of a silver dollar, for entering and exiting.

“We pour a little bit of anesthetic into the hole. It does the same thing to them that it does to us — it knocks them out,” Goodisman said. “Then we try to dig up the nest very quickly before they come to. We pull the nest out and bring it back to the lab.”

When collecting nests, Goodisman and the team wear beekeepers’ uniforms with long pants underneath for additional protection. Yellow jackets are aggressive and will push their way through air holes in the pith helmets, so the researchers cover them with tape to keep the insects out.

“I have had that happen to me, and it’s no fun at all!” said Goodisman. “If there’s an opening, they will find it and get in.”

Studying Yellow Jacket Behavior

The Goodisman Research Group is studying yellow jackets to learn about highly social behavior.

“Yellow jackets are an example of some of the most extreme and impressive social behavior that you will see in any animal, even more so than in humans,” Goodisman said. “Their social structure is similar to honeybees in that they typically have a single queen, though not always. She produces a bunch of selfless workers that work until the colony succeeds.”

The researchers are also interested in studying multiyear super colonies. Nests usually last only one season, from May to December. But when temperatures are mild, a colony can survive the winter and become massive the next year.

“We have seen this in New Zealand, Australia, and South Africa. We’re starting to see it in Florida, South Alabama, and California — super colonies the size of a car,” Goodisman said.

These changes bring up other questions, such as, are yellow jackets facing the same environmental threats as honeybees?

“The short answer is we don’t know. There’s no one studying yellow jackets the same way they’re studying honeybees,” Goodisman said. “But not all of the things that affect honeybees will affect yellow jackets.”

Honeybees have been partially domesticated and bred for successful pollination, reduced aggression, and increased honey production. Unfortunately, domestication often has unwanted side effects. For example, domesticated honeybees may display fewer behavioral defenses against parasites than feral honeybees as a consequence of the domestication process.

“Yellow jackets don’t really have that. We don’t associate yellow jackets with having a lot of diseases. They still could be subjected to pesticides, but it’s not really known,” Goodisman said.

It’s hard to tell if there has been a decrease in the yellow jacket population based on the calls the Goodisman Research Group receives.

“There has been no systematic survey that I know of,” he said. “I think a widespread survey over many years would be interesting.”

Go (Yellow) Jackets!

Goodisman’s interest in insects began when he was a child in Syracuse, New York.

“There are yellow jackets in Syracuse and all across North America, from Mexico to Alaska,” he said — indeed, they can be found all across the northern hemisphere. They are one of the most common and successful social insects.

“They’re great fun, as you might imagine. They have a lot of personality,” he said. “It’s exhilarating when you’re trying to pull them out of the ground or get them out of the house.”

His undergraduate research at Cornell University included work with insects, and he did his doctoral thesis at the University of Georgia on fire ants.

While at UGA he saw fire ants in a tray in the lab, and he thought it was “so cool.” But his work with yellow jackets didn’t start until he did postdoctoral work in Australia.

“There was some interesting research being done on invasive yellow jackets in Australia and New Zealand. I’ve been working on yellow jackets well before I came to Georgia Tech.”

It was purely coincidental that Goodisman became a professor at Georgia Tech, home of the Yellow Jackets. But it still causes the occasional raised eyebrow when he tells people about his research.

“People do a double take and ask if I’m at Tech because of my yellow jacket research. They ask if I have a yellow jacket professorship, or if I’m the ‘Chair of Yellow Jacket Research.’ It’s always a fun conversation, especially with Georgia Tech alumni.”

NOTE: Free yellow jacket nest removal. Nests will be used for research in the School of Biological Sciences. E-mail michael.goodisman@biology.gatech.edu to arrange a pickup.