Microbiology

Up to now, planet Earth's environment (including climate, flora and fauna) has evolved mostly governed by `natural laws' (physics, random mutation, natural selection, competition of species, symbiosis etc.). Increasingly, Earth's environment is affected by human activity. One of the greatest challenges facing scientists and engineers today is how to contribute to mitigating and adapting to climate change.  At this point humanity needs knowledge to make informed choices, and technology to have better options. Caltech's interdisciplinary strength allows biologists and bioengineers interested in environmental sustainability to collaborate with like-minded scientists across the institute to work towards innovative solutions.

Microbes inhabit almost every terrestrial, aquatic, and biological ecosystem on the planet, and are often instrumental in shaping their milieu. The relationships that microbes have with their environments span from symbiotic (where they confer benefits) to pathogenic (where they cause disease). Further, microorganisms live in a dynamic relationship with plants and animals, where they influence and are affected by the metabolic, immune, and nervous systems. The multidisciplinary research programs at Caltech seek to uncover and understand complex interactions between microbes and their hosts, employing computational, theoretical, and experimental approaches to investigate model systems spanning from cells, to laboratory animals, to humans. Image Credit: Mark Ladinsky

In Earth's near surface environment, there are sparingly few niches that aren't inhabited by microorganisms, from soils to sediments to oceans. Caltech's version of microbial ecology specializes in deciphering what microbes are doing in situ, how they do these things, and how their activities shape local, regional and even global geochemistry. A particular strength of our program is our ability to analyze and perturb microbial activities at the microscale using a combination of state-of-the-art imaging and analytical approaches.

Because they can grow rapidly, have small genomes, and are amenable to many types of molecular analyses, microbes provide outstanding model systems in which to study fundamental cellular processes. Labs studying microbial molecular and cellular biology draw on techniques including cryo-electron and fluorescence microscopy, protein crystallography, genetics, and biochemistry to study the bioenergetics, regulation of gene expression, protein trafficking, lipid-protein interactions, and ultrastructure of diverse organisms.

The immune system is our defense against pathogenic microorganisms. It involves an innate branch that recognizes generic aspects of pathogens and an adaptive branch that recognizes specific molecules on pathogens. Caltech laboratories are using structural biology, molecular biology, and mouse genetics to study how the immune system develops, how the immune system interacts with microbes that naturally reside in our bodies and are not pathogens, and how signals are transduced in both the innate and adaptive branches of the immune system. In addition, there is a strong translational medicine effort, with a focus on pathologies of the immune system including cancer, engineering antibodies to produce more potent vaccines, and engineering immune cells to attack cancer.