Post-doc.: Stanford University (USA)
Dr. es. sc. (equiv. Ph.D.): Swiss Federel Institute of Technology at Lausanne (EPFL, Switzerland)
Dipl. Phys. (Physics): University of Heidelberg (Germany)
The research in my group is directed towards biophysics with an emphasis on biophysical fluorescence. This highly interdisciplinary domain requires the interaction of chemists, physicists, and biologists. Only a concerted effort of these three groups will allow us to tackle the problems in the life sciences. The close proximity of departments of biology, biochemistry, chemistry, and physics at the National University of Singapore on one side and the research institutes (RIs) on the other side, allows us to develop physical and chemical methods for the study of biological questions on one hand and to apply these methods to the frontier in biology on the other hand. Our interests lie accordingly in the different areas that interact freely to advance this research field.
Construction and development of new optical tools. Optical Spectroscopy is one of the most sensitive tools available in the life sciences. Proteins can be studied not only in ensembles but as well on the single molecule level. Besides using well established methods in our group (e.g. Fluorescence Correlation Spectroscopy, Fluorescence Resonance Energy Transfer), we also plan to develop new spectroscopy and microscopy tools and new mathematical procedures to study proteins on a single molecule level in vitro and in vivo.
Study of selected proteins and protein complexes on a single molecule level and in living cells. In collaboration with the Department of Biological Sciences, the Department of Microbiology and the RIs we will study the properties of selected proteins and peptides to elucidate their function on a molecular level. At the moment we concentrate on either antimicrobial peptides and their interaction with bacterial membranes, or on the study of transmembrane proteins (G-protein coupled receptors, growth factors) and their structure, function and interactions.
One of the most interesting questions in biology is the relationship between the structure and function of proteins. With the fluorescence tools developed in our group we hope to shed some light on this question by in vitro experiments. In a complementary approach we will study the proteins in living cells because proteins are in many cases very sensitive to their environment and only when studied under physiological conditions can we determine their exact function.
Telephone: (+65) 6516 1248
Research Fellow: Mechanobiology Institute, Singapore
Ph.D., (Computation and Systems Biology): Singapore-MIT Alliance
B.Tech., (Industrial Biotechnology): Center for Biotechnology, Anna University, Chennai (India)
Understanding the diffusion properties of biofilms using fluorescent techniques.
Bacterial biofilms are communities of bacteria attached to a surface embedded in extracellular polysaccharides. In many cases, bacterial biofilms are found to be resistant to antibiotics. Currently, there are two different theories regarding the reasons for resistance. One of them is the presence of persistor cells which are known to be genetically altered and possess the antibiotic resistance genes. Another school of thought say that the extracellular polysaccharides surrounding the biofilm form a diffusion barrier to these antibiotics. It is plausible that the antibiotic resistance is conferred by a combination of both these mechanisms. The project aims to elucidate the contribution of physical mechanisms in conferring resistance to antobiotic for biofilms. This project is done in collaboration with SCELSE, Singapore Center for Environmental Life Sciences Engineering.
Research fellow: University of Strasbourg (UDS), Strasbourg, FRANCE; from 10/12 till 03/16
Research fellow: Case Western Reserve University, Cleveland, Ohio, USA; from 05/11 till 09/12
Ph.D., (Biophysics): University of Strasbourg (UDS), Strasbourg, FRANCE
M.Sc., (NanoScience): Amity University (AINT) (India)
B.Sc., (Life Sciences): Delhi University (India)
Revealing molecular events of the Dengue Virus during its infection process, its effect on the host cell, and its replication mechanisms by using Fluorescence spectroscopy and imaging techniques
Dengue Virus (DENV) is an enveloped RNA Virus that contains a 11 kb positive sense RNA as its genome and belongs to the family Flaviviridae. Despite its high clinical impact, little is known about the infectious cell entry/exit pathway. Recently, using live cell imaging techniques it has been shown that DENV particles are delivered to pre-existing clathrin-coated pits by diffusion along the cell surface. Consequently, due to membrane fusion with late endosomes, its viral content is released into the cytoplasm of host cell. Although earlier studies provide ample insight into the viral cell entry/exit mechanisms still the associated changes at molecular level within virus and the host cell are missing. I am interested in joining such missing links. To obtain this, different biophysical, bioimaging and biochemical techniques, like single molecule FRET, confocal FCCS, imaging FCS, anisotropy and time-resolved spectroscopy, will be used.
B.Sc. (Chemistry): National University of Singapore
Single plane illumination microscopy (SPIM) based fluorescence correlation spectroscopy (FCS) (SPIM-FCS) is a multiplexed technique which utilizes the combination of plane illumination from a thin light sheet with fast array detectors such as an electron multiplying charged coupled device (EMCCD) to yield quantitative spatial maps of diffusion coefficient and concentration. The freedom to illuminate any plane of a 3D sample selectively by the SPIM illumination scheme provides an avenue to decipher the z-dependence and heterogeneity of molecular dynamics in the 3D sample upon performing SPIM-FCS measurements. I am applying this technique in model membranes, live cell membranes and live zebrafish in the context of the diffusion and organization of lipids and signaling proteins in vitro and in vivo.
Research fellow: Institute of Molecular and Cell Biology-Singapore
Ph.D. : National University of Singapore
M.Sc.: National University of Singapore
B.Sc.: National University of Singapore
Generating zebrafish based models
My research interests include generating novel transgenic zebrafish to track physiological function by live imaging and developing zebrafish based strategies to assess nanomaterial function and their potential biomedical application in vivo.
Records of research activities from Google Scholar (updated on 27th April 2018)
Total publications: 35
Total citations: 1950
ResearchGate profile: https://www.researchgate.net/profile/Cathleen_Teh
BS-MS Dual Degree (Biological Sciences), IISER-Mohali (India)
Understanding the biophysical and structural basis of allosteric activation of Epidermal Growth Factor receptor using FCS and mass spectrometry
Epidermal growth factor receptor (EGFR) signaling is involved in diverse fundamental physiological processes such as cell proliferation and apoptosis. Upregulated tyrosine kinase activity of the EGFR/ErbB family is often implicated in a variety of human cancers. Even after decades of research on this signalling there are still gaps in our understanding of activation mechanism of EGFR at and across membranes. Most of the studies carried out on EGFR are on either extracellular or intracellular region of receptor but it is now speculated that transmembrane and juxtamembrane region of receptor are playing important roles in activation and regulation of EGFR signalling. Secondly, being an integral membrane protein EGFR actively interacts with its surrounding membrane environment but it is not well understood what are these interactions and how they affect the signalling. In order to fill some of the existing gaps in understanding of EGFR signalling in my project I plan to study the biophysical and structural basis of allosteric activation of EGFR signalling using Fluorescence Correlation Spectroscopy (FCS) and mass spectrometry. A combination of these two methods will provide information about lateral interactions crucial for EGFR signalling and allosteric changes taking place in the receptor across the membrane. This project will be done in collaboration with mass spectrometry focussed labs : Prof. Ganesh Anand Srinivasan's lab for structural mass spectrometry and Prof. Markus Wenk's lab for lipidomics.
B.Sc. (Chemistry-Computational): University of Colombo (Sri Lanka)
M.Sc. (Analytical Chemistry): University of Colombo (Sri Lanka)
Study of Dengue virus and infection using Fluorescence Correlation Spectroscopy
M.Sc(Integrated) Biological Sciences : BITS Pilani (Hyderabad Campus) , India
Study of development of zebrafish embryo using Light Sheet Imaging - Fluorescence Correlation Spectroscopy.
B. Tech. (Biotechnology): SRM University, Chennai, India
Investigation of membrane dynamics and organization of epidermal growth factor receptor (EGFR) by fluorescence methods
B. Sc., (Life Sciences - Molecular and Cell Biology): National University of Singapore
Studying broadly neutralizing antibodies against Dengue Virus using biophysical techniques such as time-resolved FRET, FCS and HDXMS.
Currently a PhD student in Department of Statistics and Applied Probability, National University of Singapore
M.Sc. (Quantitative Finance) & B.Sc. (Physics): National University of Singapore
Using convolutional neural networks to analyze sequences of fluorescence spectroscopy images
In recent years, neural networks have received an increased amount of attention in the ﬁeld of computer vision, especially after the introduction a convolutional neural network (CNN) architecture, called AlexNet, which won the 2012 ImageNet challenge. The state-of-the-art of visual recognition and object detection has dramatically improved and various embellishments of CNNs have been proposed since then. In this study, we aim to leverage on feature extraction capability of CNNs to analyze FCS image stacks. We want to find suitable CNNs that can estimate diffusion coefficients of particles and provide statistical properties of the estimations. This study is jointly supervised Associate Professor Adrian Roellin, from Department of Statistics and Applied Probability and Professor Thorsten Wohland.
M.Sc (Microbiology): University of Madras, India
Developmental study in zebrafish based on dynamics of wnt morphogen by generating transgenic lines with wnt3_mEGFP tagged reporter. Enabling live imaging based developmental studies in zebrafish through transgenesis in terms of molecular based techniques.