Qian Guo
BME PhD Proposal Presentation

Date:2022-06-12
Time: 8:30AM US ET
Location / Meeting Link: https://gatech.zoom.us/j/92613888352?pwd=WXlmM2RsRzJ1a2xEQlpNbHRRM1ZGdz09

Committee Members:
Dr. Huaiqiu Zhu, Dr. Peng Qiu, Dr. May Dongmei Wang, Dr. Peng Xi, Dr. Yonghong Xiao


Title: Microbial interaction and spatiotemporal evolution in bacterial pathogenesis and transmission

Abstract:
Bacterial infections have a large impact on public health. Pathogenic bacteria were harbored in multiple reservoirs covering living organisms and nonliving objects. On the one hand, they can potentially infect various sites of the human body or colonize without causing infections or symptoms. On the other hand, some pathogens can survive on environmental surfaces for several months. The spreading is another concern of pathogens, which can be transmitted via different modes, including contact, airborne, droplet, vectors, vehicular, etc. The success of pathogenic bacteria is due to their remarkable adaptability for transmission and infection. However, bacterial dynamics in the two processes were unclear. Fortunately, some clues emerged in microbial interaction and bacterial spatiotemporal evolution. As microbes mainly do not exist solely but interplay with each other in a microbial community, researchers increasingly noticed some pathogens thrive and stand out in the complex communities. Simultaneously, heritable genetic changes can arise in response to environmental changes or the host's immune response. Our lab has accumulated valuable knowledge of microbial interaction and bacterial genetic adaption through previous studies. In this proposal, we will systematically characterize the microbial interaction and spatiotemporal evolution in bacterial pathogenesis and transmission. We will investigate the microbial interactions from both microbial co-occurrence and genetic exchange perspectives. Furthermore, while single nucleotide polymorphism (SNP) was used as the single criteria for elucidating the spatiotemporal dynamics of bacteria, we integrate SNP and gene amplification to accurately describe the spatiotemporal dynamics of pathogenic bacteria. Our lab cooperated with the First Affiliated Hospital of Zhejiang University, Hangzhou, China, isolated several hundred Acinetobacter baumannii strains from the intensive care units (ICU), and sequenced the bacterial genome and the metagenome of the infection sites. The rules of bacterial dynamics will be unraveled under three important scenarios: (i) reveal the different dynamics between infection and colonization in a specific site of the human body; (ii) decrypt the advantages and adaptions of persisting lineages using A.baumannii strains circulated or sporadic in ICU; (iii) compare the pathogenesis of A.baumannii strains infecting different sites. The rich genome data is able to clarify the universal rules of microbial interaction and spatiotemporal dynamics in bacterial transmission and pathogenesis, and thus provide helpful strategies for diagnosing, treating, and preventing pathogen infection.