More Than a Century of Microbiology at UC Davis
Microbiology at UC Davis began in 1922 as a one-person teaching and research program focused on dairy bacteriology. Over the following century, it grew into a broad, interdisciplinary field spanning the campus—and into today’s Department of Microbiology and Molecular Genetics.
Throughout its history, the department has evolved alongside the biological sciences, expanding from the study of bacteria to include viruses, fungi, protozoa, genetics, biochemistry, cell biology and other areas of research. Its faculty have helped advance fundamental knowledge while preparing generations of students for careers in science, health, agriculture, biotechnology and related fields.
The Early Years
Cortland S. Mudge became UC Davis’s first bacteriologist in 1922, joining the Department of Dairy Industry in what was then the College of Agriculture. His research focused on bacterial contamination in cow’s milk, and for many years he provided all microbiology instruction on campus through a general bacteriology course.
The program began to grow after World War II. Mudge was joined by Mortimer P. Starr, who studied bacterial diseases of plants, and Donald M. Reynolds, whose research focused on bacterial degradation of chitin. Graduate instruction in microbiology began in 1949 through a multidisciplinary graduate group that brought together faculty from Dairy Science, Plant Pathology, Food Science, Veterinary Medicine and other fields.
This collaborative structure established an interdisciplinary approach to microbiology that continues at UC Davis today.
Establishing the Department
Bacteriology became its own department in the newly established College of Letters and Science in 1951, with Mudge serving as its first chair. Allen G. Marr joined the faculty the following year and worked with Mudge, Starr and Reynolds to develop the curriculum for a new undergraduate major in bacteriology.
The major enrolled five students in its first year and emphasized the fundamental biology of microbes rather than primarily their medical applications. By the mid-1960s, the department offered a Bachelor of Science degree with expanded preparation in mathematics and the physical sciences.
The department also built an emerging reputation in microbial physiology, metabolic diversity and genetics. Robert E. Hungate, known for pioneering methods used to cultivate anaerobic microorganisms, became chair in 1956. Geneticist Monica Riley joined the faculty in 1960, bringing expertise in the physiology and genetics of E. coli and becoming the department’s first female faculty member.
Expanding Beyond Bacteria
The department grew substantially during the 1970s and 1980s as new faculty broadened its research in microbial physiology, genetics, virology, ecology and gene regulation. Its research increasingly extended beyond bacteria to include viruses, fungi and other microorganisms.
These changes reflected a larger transformation taking place across the life sciences. Advances in molecular biology were making it possible to clone genes, create transgenic organisms and investigate biological processes at the molecular level.
In recognition of its expanding scope, the Department of Bacteriology became the Department of Microbiology in 1988.
The Rise of Molecular Genetics
During the 1990s and 2000s, genetics, genomics and biochemistry became increasingly prominent within the department. Faculty developed research programs spanning DNA repair and recombination, chromosome biology, gene regulation, cellular stress, aging, microbial ecology, host-microbe interactions and environmental microbiology.
Microbes remained essential research subjects, but faculty also increasingly used microbial and non-microbial systems to investigate cellular processes shared across many forms of life. This expansion helped shape the department’s modern identity and strengthened connections with researchers across the biological sciences, medicine, agriculture and engineering.
Becoming Microbiology and Molecular Genetics
In 2013, the department adopted its current name: the Department of Microbiology and Molecular Genetics. The change recognized the growing importance of genetics across its research and teaching, including work conducted in non-microbial systems. It also reflected the close historical relationship between the two fields, as research in microorganisms helped establish many of the foundational principles of molecular genetics.
The department continued to expand its interdisciplinary reach through collaborations and joint faculty appointments spanning biological sciences, engineering, mathematics, medicine and other fields. At the same time, it strengthened undergraduate education through new courses, learner-centered teaching and expanded laboratory experiences.
In 2021, the undergraduate major was renamed Molecular and Medical Microbiology to better represent its breadth and its connections to contemporary research and human health.
A Second Century of Discovery
Today, the Department of Microbiology and Molecular Genetics investigates questions ranging from microbial physiology and host-pathogen interactions to genome stability, immunology, aging and cancer. Its faculty use diverse experimental systems and interdisciplinary approaches to understand how microbes, genes and cells function—and to translate new discoveries into teaching and training.
More than a century after microbiology began at UC Davis, the department continues to evolve with the field while building on its longstanding commitments to fundamental research, collaborative discovery and student education.