USC Dornsife mourns loss of Jan Amend, visionary scientist who helped forge geobiochemistry field

Jan Amend, divisional dean for the life sciences and professor of Earth sciences and biological sciences at USC Dornsife College of Letters, Arts and Sciences, passed away unexpectedly on Feb. 1 at his home in Palos Verdes, Los Angeles. He was 59.

Renowned as a leader, researcher, mentor and collaborator, Amend brought his passion for probing the energetic interplay between life and its environment to USC Dornsife in 2011 and leaves behind an indelible legacy of scientific discovery and cross-disciplinary partnerships.

In support of NASA’s mission for life detection and habitability on Mars and as leader of a NASA Astrobiology Institute based at USC Dornsife, Amend was at the forefront of exploring life in extreme conditions, shedding light on the potential for life beyond Earth. He also sought to understand the origins and subsurface operations of life on our own planet.

In pursuit of these questions, Amend assembled teams that brought together geochemists, geologists, and microbiologists to combine laboratory experimentation with fieldwork in extreme environments. This collaborative approach led them from the depths of a repurposed gold mine in South Dakota to the expansive biosphere beneath the ocean’s surface.

“His science was unique and constitutes a fundamental shift in our understanding of the thermodynamics of life in the environment,” said Frank Corsetti, chair of the department of Earth sciences. “Jan was also a tremendous advocate and facilitator for countless scientists as well as the field of geobiology. He facilitated the growth of geobiology across the globe.”

Among Amend’s many scientific achievements was the research he conducted that helped to reveal the many different ways that microbes could get energy depending on their environment — and how much they could obtain in each case. Working with Doug LaRowe, associate (research) professor of Earth Sciences, Amend showed that microbes could survive on very low fluxes of energy, challenging existing notions of life’s limits.

“While humans combine food with the oxygen that we breathe in a reaction to get energy, microbes are capable of obtaining energy from a far wider — and weirder — set of reactions,” explained LaRowe. “For instance, Jan worked with organisms that can eat and breathe arsenic.”

In his capacity as USC Dornsife’s divisional dean for the life sciences, Amend was instrumental in recruiting eminent faculty, solidifying USC Dornsife’s position as a leading global center of marine microbiology and marine ecology. His energy and dedication to his leadership role extended beyond his own areas of research and was exemplified by his successful recruitment of  distinguished faculty across multiple departments in the life sciences, including biological sciences, quantitative and computational biology, and psychology. His leadership of the National Science Foundation Science and Technology Center for Dark Energy Biosphere Investigations (C-DEBI) was instrumental in fostering cutting-edge research into the deep subsurface biosphere.

“Jan was a brilliant scientist and a generous and beloved mentor who was known for bringing out the best in teams of colleagues and students,” said USC Dornsife Dean Amber D. Miller. “He was also a talented and cherished member of my senior leadership team who played a key role in advancing our core mission of academic excellence. I particularly miss his warmth, quick wit, and sage advice. His absence leaves an unfillable void, but the lasting influence that he has had on countless colleagues and students will live on.”

Inspired to honor

Amend was born in Montreal on June 2, 1964, to German parents Gerda (née Laue), a seamstress, and Jürgen Amend, a shipping company executive. They moved when Amend was 3 to a small town outside Hamburg, Germany, where he played soccer and visited his uncle’s vegetable farm, a place Amend adored.

When Amend was 12, the family moved to California, where they settled in the L.A. neighborhood of Palos Verdes, within sight of the ocean and just a couple of miles from where Amend would eventually return to live with his own family. The transition was initially challenging for Amend and his older sister, Meike, both of whom spoke very little English then.

He arrived in the US with not only a burgeoning passion for science and soccer but also the profound influence of his family’s history. His treasured possession, a baptismal letter from his paternal grandfather — who bravely opposed Nazi ideology during WWII — was a call to live a life of honor.

The letter, written just after Amend was born, conveyed his grandfather’s hope for a future generation to redeem Germany’s honor by living good lives. This message resonated deeply with Amend, as his wife, Andrea Amend, attested. She reflected that his life of integrity, generosity, and compassion indeed lived up to his grandfather’s aspirations and would have filled him with pride.

USC Dornsife’s Moh El-Naggar, divisional dean for the physical sciences and mathematics, echoed this testament to Amend’s character.

“Jan somehow brought both warmth and exceptionally high standards to everything he said and did,” said El-Naggar. “This was the foundation of his tremendous accomplishments as a scientist, academic leader and mentor. He cared for, challenged and lifted all of us who worked closely with him.”

A stellar scientist

A first-generation college student, Amend graduated with a BA in chemistry from the University of California, San Diego, in 1987. After spending a year as a laboratory assistant in a chemical plant in Germany — an experience that convinced him that a career in chemistry was not for him — he realized his true calling lay in academia. He applied to the University of California, Berkeley to study geochemistry, earning his PhD in 1995.

Amend’s time at UC Berkeley proved seminal. Not only did he meet his future wife, also a chemistry major, but his career-long research focus on energy was sparked there.

Amend’s early research involved unraveling the intricacies of how rocks, minerals, and water interact energetically under varying conditions of temperature and pressure. Discussions with his larger-than-life doctoral advisor Harold “Hal” Helgeson, a pioneering theoretical geochemist, and Everett Shock, the geochemist who became Amend’s mentor, led to some groundbreaking ideas. Together, they pondered a radical possibility: could microorganisms be actively shaping these mineral-water interactions to harness energy?

“This was a novel, mind-blowing concept, the blending of biology and geology at a time when biologists worked in their realm and geologists in theirs,” Andrea Amend said. “The field of biogeochemistry was born.”

In a seminal publication, Amend and his mentor Shock presented a compelling case that microbes dwelling in seafloor hydrothermal systems might be capable of synthesizing amino acids — the essential components of proteins — without expending energy. This finding suggested a remarkable efficiency in the biochemical processes of these organisms and hinted at a broader potential for life in extreme environments.

Emboldened by the insights gained through his computational research at Berkeley, Amend ventured into the field to put theory into practice. His hands-on approach to collecting fluid and microbial samples led to breakthroughs beyond the digital realm, including the identification of previously unknown microbial species. This transition from computational models to direct fieldwork exemplified Amend’s dedication to comprehensive scientific inquiry.

Shortly after his marriage in 1995, Amend embarked on a journey that would mark the beginning of a pivotal phase in his career. With an NSF-NATO postdoctoral fellowship in hand, he and his wife set off for the University of Palermo, Italy. While in the uncharted terrains of Sicily and the Aeolian Islands, he sought to uncover the secrets of life in extreme environments, meticulously collecting samples, cultivating microbes, and performing analyses on the water and minerals. His rigorous scientific pursuits aimed to unravel which reactions the microbes were using to fuel their existence and quantify the energy they derived from these processes.

After his time in Sicily, Amend undertook postdoctoral work with Shock, moving from Washington University in St. Louis to the University of Washington, Seattle and then back again. They continued working together there for many years, building labs and mentoring students in biogeochemistry as they continued to integrate geochemistry and microbiology. Amend remained at WashU for 14 years, becoming a tenured professor before joining USC Dornsife.

“A force for good”

At USC Dornsife, Amend was known not only for his impressive research, but also for his exceptional ability to forge connections, fostering cross-disciplinary collaborations within USC, across academia, and with industry. His reputation as a generous and dedicated mentor was equally notable, marked by a sincere interest and investment in others and their ideas.

“Jan really perfected being a cheerleader and giving you the advice that you needed to hear, even if you didn’t want to hear it,” said Annette Rowe, a former postdoctoral fellow with C-DEBI and now assistant professor of biological sciences at the University of Cincinnati, Ohio.

“He was such a genuine person; you had no choice but to take what he said to heart and learn and grow from it. And his self-deprecating sense of humor always softened the blow.”

Amend also served as a long-standing mentor to former USC Dornsife postdoctoral fellow Maggie Osburn. Now an associate professor of geobiology at Northwestern University, Osburn remembers Amend as “a force for good” within the biogeoscience community.

“A truly unique aspect of his temperament was that he approached all scientists as both colleagues and friends. There was no wall of formality; Jan wanted to know both your science and you as a person,” she said. “As a mentor, Jan was the perfect balance between high expectations and empowering people to do what they do well.”

Avid sportsman

Amend nurtured an enduring love of the ocean. As a skilled scientific diver, he explored diverse aquatic sites from Papua New Guinea to the Mediterranean, collecting microbe samples in their natural habitats. At home in California, he enjoyed swimming, snorkeling, boogie boarding and cycling along the beach from Palos Verdes to Malibu.

A passionate, lifelong soccer fan, Amend and his wife traveled to 30 states in 30 days to follow the German national team during the 1994 World Cup.

Amend’s enthusiasm for sports extended beyond spectating. He played soccer and tennis, enjoyed skiing and running, and even rowed crew at UC San Diego, committing to a diet to join the more competitive lightweight team. In later years, he competed in two Half Ironmans, hiked the Five Peak Challenge in Boulder and participated in the Triple Bypass Ride, both in Colorado.

After his vigorous morning exercise routine, he would jump into his beloved British Racing Green Mini Cooper Convertible to drive to campus, always insisting — despite passengers’ protests on chillier days — on keeping the top down to make the most of the California sunshine.

Amend’s boundless energy and drive extended to his work at USC, said Kenneth Nealson, emeritus professor of Earth Sciences. “On top of being a dean, he ran a lab, taught courses and directed both the C-DEBI and the NASA Astrobiology programs,” Nealson said. “He never seemed to run out of energy and he was just so good at it all.”

An outstanding colleague — and human

Throughout his life, Amend’s thoughtfulness, generosity and kindness were exemplified in ways large and small. He was a believer in the German concept of “Vorfreude” — joyful anticipation.

His wife remembers the tremendous pleasure he took in buying fresh strawberries every Wednesday and bringing them to the USC Dornsife dean’s suite, where he would discreetly place them in the kitchen for staff and visitors to enjoy. She said her husband loved to peek into the room after a meeting, see a dent in the fruit bowl and know the enjoyment his gift was giving to others.

Joe Arvai, Dana and David Dornsife Chair, professor of psychology and biological sciences and director of the Wrigley Institute for Environment and Sustainability, emphasized that it was these human qualities of thoughtfulness and willingness to share time that made Amend such an outstanding colleague.

“He was someone I could talk with about what was happening outside of work, and he helped me make sense of the world — and our place in it,” Arvai said.

Amend is survived by his wife, Andrea; his children, Emma and Finn; his sister, Meike Wanberg; and his mother, Gerda Amend.

USC Dornsife is planning a celebration of Amend’s life. Details will be announced soon.