Date: 23 November 2023 (Thursday)

Time: 5:00 pm – 6:00 pm

Venue: Cheung Kung Hai Lecture Theatre 2, G/F, William M.W. Mong Block, 21 Sassoon Road

5:00 p.m.

Presenter: Ying DOU (MPhil candidate)
Primary Supervisor: Prof. Jiandong HUANG
Presentation Title: Elucidating the mechanisms of PSMs-induced cell division defect in Staphylococcus aureus
Abstract: Staphylococcus aureus is a Gram-positive pathogen that causes various diseases and resists many antibiotics, posing a serious threat to global health. One of its key virulence factors is phenol-soluble modulins (PSMs), a family of small cytolytic peptides that are encoded in the core genome and exported by the phenol-soluble modulin transporter (Pmt). In this study, we engineered mutant strains of S. aureus that lack PSMs, Pmt, or both, and found that only the Pmt-deficient strain showed defects in cell division, as observed by TEM. This suggests that PSMs have a novel role in regulating cell division, which has not been reported before. We aim to elucidate the mechanism and the molecular players involved in this process, and to identify potential targets for developing new anti-staphylococcal drugs.

5:30 p.m.

Presenter: Yige HE (MPhil candidate)
Primary Supervisor: Prof. Jiandong HUANG
Presentation Title: In situ anti-tumor therapy based on reprogrammed bacteria
Abstract: The cold tumor microenvironment presents a significant challenge that in achieve optimal therapeutic outcomes. Anti-tumor therapies such as immune checkpoint inhibition have demonstrated limited benefit in nonresponding patients. However, many bacteria possess inherent capabilities to target tumors via diverse mechanisms, including chemotaxis and the hypoxic tumor environment. Historically, bacteria have proven effective in impeding tumor growth, making them one of the earliest forms of immunotherapy. Nonetheless, certain obstacles remain, such as safety concerns and the need for more precise tumor targeting.

My project focus on using leveraging synthetic biology techniques to reprogram bacteria, enabling their infiltration of tumors and modification of the cold tumor microenvironment. These reprogrammed bacteria possess the ability to exclusively proliferate within tumors, while avoiding normal organs, and can subsequently lyse to release therapeutic agents directly into the tumor. Our data indicates that these reprogrammed bacteria effectively deliver genetic cargo and arrest tumor growth across various tumor models. Our ongoing efforts are focused on characterizing the underlying mechanisms by which bacteria can alter the cold tumor microenvironment.

ALL ARE WELCOME

Should you have any enquiries, please feel free to contact Jerry Siu at 3917 6912.