Friday, May 3
9:30 AM - 4:00 PM
Science Center (Room 4102)
The talks will not be livestreamed, but a recording will be available online afterwards.
9:30 AM
Breakfast
10:00 AM - 11:30 AM
Coral Reef Arks & the BioToy universe
Forest Rohwer
San Diego State University
Tens-of-millions of life forms, the most abundant and biodiverse being the bacteriophage, call coral reefs home. All of these diverse life forms are interacting with each other in ever changing ways and all of this activity occurs within the dynamical Gaian biosphere. This makes coral reefs incredibly complex. To understand the keystone processes in these ecosystems, we are using Coral Reef Arks (coralarks.org) to try to build coral reefs. A major challenge to this effort is having a realistic model of coral reef. To address this limitation, we are using a thermodynamics approach. I will discuss how Coral Reef Arks and thermodynamics are helping us understand these fascinating ecosystems.
11:30 AM
Break
12:00 PM - 1:30 PM
From precise microbial genomics to precision medicine
Ami S Bhatt
Stanford University
More than 1,000 species of bacteria, archaea, viruses and fungi live in the human gut. Far from being passive passengers, these organisms strongly interact with one another and with their host’s metabolism and immune system. Compelling early experiments have demonstrated associations between the intestinal microbiome composition and obesity, cardiovascular diseases, and certain cancer chemotherapies’ efficacy. Yet teasing apart the mechanisms by which microbes impact host health has been challenging. To accelerate an otherwise challenging, slow and tedious process and to deconstruct mechanisms, we must critically examine our existing “tool kit” for studying the microbiome, and mature our measurement tools to meet these challenges. Our translational laboratory builds and designs observational and interventional clinical cohorts to study. We have also worked to develop genomic tools to study strain level dynamics of the microbiome, how microbial genomes change over time and how microbes use hidden “microproteins” to communicate with each other and their human hosts. In this presentation, I will speak about: (1) how our focus on mobile genetic elements our lab’s recent discovery of intragenic inversion as a previously unappreciated mechanism of generating genetic diversity in microbial genes, and (2) our efforts to decipher microprotein-based communication and warfare in the human gut microbiome.
1:30 PM
Lunch
2:30 PM - 4:00 PM
Bacterial motility, suicidal chemotaxis and the evolution of antibiotic resistance
Nuno Miguel Oliveira
University of Cambridge
The idea that in natural environments bacteria do not live in homogenous conditions and are often exposed to gradients of nutrients, toxins and other chemicals is hardly surprising to any microbiologist. And yet, most of what we know about microbial life comes from shaking flasks, namely in the context of microbial stress responses and antimicrobial adaptation. What if bacteria could bias their motility in antibiotic landscapes and adjust their physiology accordingly? I will show that they do. I will show that, counterintuitively, a subpopulation actively moves towards high concentrations of antibiotics as part of a suicidal programme where cells upregulate their own antimicrobials as they move along. This perplexing bacterial behaviour that challenges our intuition can be understood as part of a counter-attack response against antibiotic-producing competitors, and resembles the aggressive behaviours found in social insects such as honeybees. My talk will have three parts. I will start by characterizing the diverse ways bacteria have to move, with particular focus on how bacterial cells bias their motion on surfaces via Type-IV pili in developing biofilms (twitching chemotaxis). Then, I will build on this idea and show how surface-attached bacteria navigate antibiotic gradients, where I will compare such “antibiotic taxis” with how bacterial cells navigate gradients of nutrients and other canonical chemoeffectors. Finally, I will show that bacterial motility can determine the evolution of antibiotic resistance. By means of computational modelling and mathematical analysis, I will show that bacterial motility can drive the adaptation rate of bacteria in stress landscapes such as antimicrobial gradients. Iconically, it was the fact that bacteria were “very prettily a-moving,” that caught the attention of van Leeuwenhoek, and thus made us aware of bacteria themselves. My talk will highlight that, in addition to being pretty, bacterial motility can help us to understand how bacteria respond and adapt to stress.
Organizers: Ahmed Al-Harraq, Alejandro Martinez-Calvo, and Carolina Yuste
Sponsored in part by the Center for the Physics of Biological Function, a joint effort of Princeton University and the CUNY Graduate Center.