微生物学认识到，微生物发明深刻影响了整个地球历史上生物圈和地球圈的各个方面。现在已知真核生物中许多重要的分子和细胞过程首先出现在细菌和古细菌中，微生物的代谢活动控制着许多地球化学循环。微生物已经并且将继续在许多科学领域中充当模型系统，范围从基本生物学和生物化学到对控制生物系统的物理原理的理解，到新出现的鲁棒性，稳定性和复杂网络设计的问题。人们对微生物在社区内的相互作用以及微生物群落与其环境之间的相互作用知之甚少。然而，研究这些相互作用是理解自然界基本关系的关键，例如：1.）反馈回路将水生或陆地生境中的微生
Caltech's version of microbiology is unique. Faculty from several divisions seek to understand microbial systems at various spatial and temporal scales: from the molecular to the global, and from the present to the past. We recognize and celebrate that microbes have profoundly shaped every aspect of the biosphere and geosphere. We work with model microbes to explore diverse subjects, ranging from basic biology and biochemistry, to the understanding of physical principles governing biological systems, to emerging questions of robustness, stability, and design in complex networks. We also seek to understand how microbes behave within populations and communities, as well as how microbial communities impact their environments. Our research includes studies of pathogenic and non-pathogenic viruses, and use the tools of molecular biology, cell biology, physiology, and systems biology to understand how viruses enter cells, make copies of themselves, and emerge from cells to infect more hosts, all while evading the host immune response. Finally, Caltech microbiologists seek to leverage the metabolic versatility of microbes as engineering components to solve societal problems.