The Vaginal Microbiome

The human vagina is home to a community of bacteria, viruses, and fungi, whose makeup impacts the sexual and reproductive health of the host. In the Hussain Lab, we take an ecological and evolutionary approach to investigate the forces shaping the diversity and dynamics of the vaginal microbiome. We use fundamental bacteriology and virology techniques in the wet lab to reveal the interactions between vaginal microbes, as well as computational methods and comparative genomics to study the impacts these interactions have on microbial evolution and ecosystem stability. Our ultimate goal is to use our findings to help design genomically- and ecologically-informed therapies for women’s health.

Research Themes

Phage-driven evolution of the vaginal microbiome


As one of the main predators of bacteria, bacteriophages (phages) play an important ecological role in regulating the abundance and diversity of bacterial populations. Through highly specific predatory interactions, these bacteria-infecting viruses promote gene transfer in their hosts through negative frequency-dependent selection, and as a result, are thought to be key drivers of the immense genetic diversity seen in microbial genomes. However, the impact of phages on bacterial diversification in natural ecosystems, including the human microbiome, is poorly understood. In the Hussain Lab, we investigate virus-driven evolution of microbes living in the human vagina. By isolating and sequencing the genomes of key vaginal bacteria and the viruses that infect them, and testing the interactions between them, we aim to determine the impact of phages on the evolution of the vaginal microbiome. Questions of interest: Who are the lytic phages that infect vaginal bacteria and whom do they kill? What strategies have vaginal bacteria developed to defend themselves against their viral predators? What environmental factors (menses, sex, changes in hormones, etc.) lead to the induction of prophages from vaginal bacteria?

Microbe-microbe interactions shaping the vaginal microbiome


Wild microbes live in complex communities, constantly interacting with one another. In the Hussain Lab, we seek to understand how mutualistic and antagonistic interactions shape the diversity and dynamics of the vaginal microbiome. Studying microbe-microbe interactions in the lab not only helps us create better models of microbial community dynamics, but also helps us pursue our therapeutic goals by teaching us about the properties of probiotics and prebiotics that promote healthy states in the vaginal microbiome. Currently, we are particularly interested in the role of bacteriocins in shaping interactions. Questions of interest: What small molecules have different bacteria engineered to work cooperatively or compete with co-occurring bacteria in the vagina? How do bacteria evolve resistance to different antimicrobial compounds produced in or applied to the vaginal microbiome?