Dynamics Imaging of Biomolecular Assemblies

 

Single cells are the building blocks for all biological systems; yet they are inherently complex with intricate networks of dynamic biomolecular assemblies made up of proteins, coenzymes, ligands, DNA, RNA and lipids. In addition, these molecular assemblies are dynamically changing their sizes, conformations and intermolecular interactions in response to specific chemical, environmental or biological cues. In Heikal laboratory, we are using fluorescence microscopy (confocal, two-photon, TIRF, and wide-field) and spectroscopy (time-resolved fluorescence, time-resolved anisotropy, FLIM, and FCS) to investigate molecular and cellular biophysics. These noninvasive and quantitative approaches complement traditional biochemical techniques on purified biomolecules from cell lysates.

Our interdisciplinary research interests are focused on understanding the molecular underpinning of cellular processes such as energy metabolism in living cells, mitochondrial dysfunction, biomimetic membranes, and immunoglobulin E receptor signaling. We are also interested in studying protein & molecular dynamics, protein-protein interactions, macromolecular crowding, and spectroscopy. In addition, we are developing fluorescence-based micro-spectroscopic tools, image processing algorithm and modeling.

Students in Heikal laboratory (both undergraduates and graduates) are trained on a number of analytical, biophysical, and biochemical methods that include cell culture, model membrane assemblies, molecular dynamics, optical microscopy and ultrafast laser spectroscopy. Different aspects of scientific research (e.g., experimental design, data and image analysis, critical thinking, scientific writing, communication and teamwork skills) are also emphasized. The students in Heikal laboratory also gain an appreciation of interdisciplinary research at the interface of traditional disciplines of chemistry, biochemistry, biology, physics, and mathematics.

 

News

 

Ahmed A. Heikal will be an invited speaker at the Ultrafast Imaging and Spectroscopy conference in the 2015 SPIE Optics and Photonics, San Diego, CA, August 9 - 13, 2015.

Ahmed Heikal has just published the following peer-reviewed paper: Zhihua Xu, Feng Gao, Elena Makarova, Ahmed A. Heikal, and Victor Nemykin. 2015. "Energy Transfer from Colloidal Quantum Dots to Near Infrared Absorbing Tetraazaporphyrins for Enhanced Light Harvesting", The Journal of Physical Chemistry (C); 119(18): 9754 - 9761 (DOI: 10.1021/acs.jpcc.5b01603).

Dhanushka Wickramasinghe, Randi Timerman, Jillian Bartusek, and Ahmed A. Heikal. “Partitioning and Diffusion Dynamics of Fluorescently Labeled FTY720 in Resting Epithelial Cells”. InAdvanced Time-Correlated Single-Photon Counting Applications”, Wolfgang Becker (Editor), Springer Series in Chemical Physics 111, Springer (ISBN: 978-3-319-14928-8, DOI: 10.1007/978-3-319-14929-5), Chapter 10, pp 339 - 355 (May 2015).

Ahmed Heikal has participated in the "70th International Symposium on Molecular Spectroscopy", June 22 - 26, 2015, at the University of Illinois at Urbana-Champaign.

Spencer Gardeen, Joseph L. Johnson, and Ahmed A. Heikal. "Fluorescence microspectroscopy assessment of the in vitro dimerization of BACE1-GFP fusion protein in cultured cells", The 249th American Chemical Society Meeting, Symposium: Current Topics in Biological Chemistry, Division of Biological Chemistry, Denever, CO, March 22 - 26, 2015.

Rochelle Warner, Tyler Floden, Ahmed A. Heikal, and Erin Sheets. "Molecular and Mechanical Manipulation of Membrane Domains in Planar Supported Bilayers". The 59th Biophysical Society Meeting, Baltimore, MD, February 7 - 11, 2015.

Ahmed A. Heikal was an invited spkeaker at the Department of Chemistry, St. Olaf College, on March 5th, 2015.

Ahmed A. Heikal served as the Acting Assistant Department Head for the UMD Department of Chemistry & Biochemistry during the Fall semester of 2014-15.

Vladimir V. Ghukasyan and Ahmed A. Heikal have co-edited a book entitled, "Natural Biomarkers for Cellular Metabolism: Biology, Techniques, and Applications", which was published by Taylor & Francis, CRC Press (October 7, 2014, 408 Pages), ISBN: 9781466509986), Series in Cellular and Clinical Imaging (Senior Editor: Ammasi Periasamy).

Vishwasrao, H.D., Q. Yu, K. Hewawasam, Ahmed A. Heikal. “Polarization Imaging of Cellular Autofluorescence”. In “Natural Biomarkers for Cellular Metabolism: Biology, Techniques, and Applications, Ghukasyan, V. and A.A Heikal (Editors), Series in Cellular and Clinical Imaging, Dr. Ammasi Periasamy (Senior Editor), Taylor & Francis Books, (October 2014).

John Alfveby, Randi Timerman, Monica P. Soto Velasquez, Dhanushka W.P.M. Wickramasinghe, Jillian Bartusek, and Ahmed A. Heikal. 2014. "Time- and Polarization-Resolved Cellular Autofluorescence Towards Quantitative Biochemistry on Living Cells". Ultrafast Nonlinear Imaging and Spectroscopy II, Zhiwen Liu, Iam Choon Khoo, Demetri Psaltis (Editors), Proc. of SPIE Vol. 9198 91980U, Pages 1-15 (invited paper).

Ahmed A. Heikal. 2014. "Natural Bioluminescence in Living Cells for Biomedical Diagnostics". SPIE Newsroom, DOI: 10.1117/2.1201410.005615, October 10, 2014.

John Alfveby defended his MS Thesis successfully on July 21, 2014. The final thesis was accepted by the Graduate School, University of Minnesota, on August 29, 2014. John will be applying for a PhD program for Fall-2015 following a year of job experience. Congratulations John and Best Wishes.

Ahmed Heikal was an invited speaker at the Ultrafast Imaging and Spectroscopy conference in the 2014 SPIE Optics and Photonics, San Diego, CA, August 17 - 21, 2014.

Ahmed Heikal, "Searching for Self in a Diverse World", Duluth News Tribune (Thursday, July 24, 2014).

Ahmed Heikal, "Egyptian Women are the Forgotten Heroes", Duluth News Tribune (Sunday, June 1, 2014).

Ahmed Heikal has participated in a session on "Spectroscopy in Kinetics and Dynamics" in the "69th International Symposium on Molecular Spectroscopy", June 16 - 20, 2014, at the University of Illinois at Urbana-Champaign. He also chaired a Mini-symposium on "Spectroscopy in Kinetics and Dynamics."

Ahmed Heikal was named "Professor of the Year" by PD1 students (class 2017) for the academic year 2013-14, College of Pharmacy, University of Minnesota, Duluth Campus.

Ahmed Heikal has just published a peer-reviewed paper entitled, "Time-resolved fluorescence anisotropy and fluctuation correlation analysis of major histocompatibility complex class I proteins in fibroblast cells", Methods, (66) 283-291 (2014). This paper was published in a special issue of Methods, entitled "Advanced Light Microscopy Imaging in Biological Sciences."

Randi Timerman (undergraduate) and John Alfveby (MS candidate) from Heikal Group have presented their research (two posters) at the 58th Biophysical Society Meeting, San Francisco, CA (February 15 - 19, 2014). Chang Thao (McNair Scholar), Holly Israelson, Jillian Bartusek, Dhanushka Wickramasinghe, and Robb Welty were also co-authors.