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S. Saif Hasan, PhD

Academic Title:

Assistant Professor

Primary Appointment:

Biochemistry and Molecular Biology

Additional Title:

Group Leader, CBT and IBBR


Rockville MD

Phone (Primary):


Education and Training

  • B.Sc., Biochemistry, Aligarh Muslim University, India, 2004
  • M.Sc., Biotechnology, University of Pune, India, 2006
  • Ph.D., Biological Sciences, Purdue University, USA, 2013
  • Postdoctoral Research, Purdue University, USA, 2019


My doctoral research on the structure-function studies of the hetero-oligomeric cytochrome b6f complex of the photosynthetic membranes has given me experience in genetic modification, expression, purification, crystallization, and structure determination of membrane protein complexes.

As a post-doctoral researcher, I investigated the structural basis of interactions of membrane-containing flaviviruses and alphaviruses with neutralizing antibodies, thus expanding my research expertise to cryo-electron microscopy, while utilizing my experience in membrane protein biochemistry and structural biology.

As an independent investigator at the University of Maryland, I utilize my expertise in structural biology of multi-subunit, integral membrane protein complexes to investigate the structure-function of membrane proteins involved in oncogenic trans-membrane signaling and viral assembly.

My laboratory is located in the Center for Biomolecular Therapeutics (CBT) within the Institute for Bioscience and Biotechnology Research (IBBR) in Rockville, MD (address below).

IBBR is home to a new 200 keV Talos Arctica TEM equipped with a direct electron detector for high-resolution structure determination. A second 200 keV TEM, a Glacios fitted with a direct electron detector, will be acquired soon.

Center for Biomolecular Therapeutics (CBT)
Institute for Bioscience and Biotechnology Research (IBBR)
9600 Gudelsky Drive
Rockville, MD 20850

Research/Clinical Keywords

Cancer Biology, Cryo-Electron Microscopy, G-Proteins, Membrane Proteins, Structural Biology, Transporters, Trans-Membrane Signaling and Transport, Viral Structures, Vesicular Trafficking, X-Ray Crystallography

Highlighted Publications

Hasan SS, Yamashita E, Baniulis D, Cramer WA. Quinone-dependent proton transfer pathways in the photosynthetic cytochrome b6f Proc Natl Acad Sci U S A. 2013;110(11):4297-302. PubMed PMID: 23440205; PubMed Central PMCID: PMC3600468.

Hasan SS, Cramer WA. Internal lipid architecture of the hetero-oligomeric cytochrome b6f Structure. 2014;22(7):1008-15. PubMed PMID: 24931468; PubMed Central PMCID: PMC4105968.

Hasan SS, Miller A, Sapparapu G, Fernandez E, Klose T, Long F, Fokine A, Porta JC, Jiang W, Diamond MS, Crowe JE Jr, Kuhn RJ, Rossmann MG. A human antibody against Zika virus crosslinks the E protein to prevent infection. Nat Commun. 2017;8:14722. PubMed PMID: 28300075; PubMed Central PMCID: PMC5356071.

Hasan SS, Sun C, Kim AS, Watanabe Y, Chen CL, Klose T, Buda G, Crispin M, Diamond MS, Klimstra WB, Rossmann MG. Cryo-EM structures of Eastern Equine Encephalitis Virus reveal mechanisms of virus disassembly and antibody neutralization. Cell Rep. 2018;25(11):3136-3147. PubMed PMID: 30540945; PubMed Central PMCID: PMC6302666

Hasan SS, Sevvana M, Kuhn RJ, Rossmann MG. Structural biology of Zika virus and other flaviviruses. Nat Struct Mol Biol. 2018;25(1):13-20. PubMed PMID: 29323278 (review article)

Complete List of Publications:

Research Interests

Structural Biology of Multi-Subunit Membrane Protein Assemblies

Biological membranes form organelles, which are intracellular compartments that perform specialized biochemical functions. These compartments communicate with each other through the transport of protons, electrons, ions, molecules, and large, supra-molecular assemblies. Biological transport often involves proteins that are embedded in biological membranes. Transport proteins face two distinct challenges that interfere with normal cellular functions. The first challenge involves genetic errors in transport proteins that lead to altered expression and/or structural changes, which compromise trans-membrane biological communication and manifest as diseases such as cancer.

Biochemical reactions in cellular organelles include not only the biosynthesis of components required for cellular homeostasis, but also of biomolecules involved in viral assembly. The second challenge faced by transport proteins involves enveloped viruses, which exploit cellular compartments and membranes during viral replication and assembly. Often, viral replication takes place in multiple cellular compartments. Final assembly of infectious progeny virus particles requires the transport of viral components from various organelles to the site of assembly. Successful exploitation of host membrane proteins involved in transport processes requires that viral components either mimic cellular factors or hijack factors involved in interactions with host membrane proteins. Hence, structural information about the architecture of complexes of cellular membrane proteins and viral proteins will provide insights into the molecular basis of successful viral infections.

Research in the Hasan laboratory focuses on determining the atomic and molecular architecture of membrane protein complexes responsible for biological transport, disease, and virus assembly. Our research aims to enhance the understanding of how signal transduction and transport by membrane proteins achieves long-range biological communication. We use single particle cryo-electron microscopy (cryo-EM) of large, multi-subunit assemblies and X-ray crystallography of simpler proteins to gain high-resolution insights into the molecular basis of trans-membrane communication and protein-protein interactions. 

Awards and Affiliations

  • 2003 & 2004 : ‘JNCASR – Summer Research Fellowship’ awarded by the Jawaharlal Nehru Centre for Advanced Scientific Research (Bangalore), Rajiv Gandhi Foundation (New Delhi) and Department of Science and Technology (Government of India).
  • 2005: University Medal for highest marks in Bachelor of Science (Honors) Biochemistry awarded by the Aligarh Muslim University, Aligarh (India).
  • 2005: University Medal for highest marks in the Faculty of Life Sciences awarded by the Aligarh Muslim University, Aligarh (India).
  • 2005: Nationally competed scholarship for higher studies awarded by the Bharat Petroleum Corporation Limited (India).
  • 2006: Placed in top 20 percentile of awardees of Junior Research Fellowship for Ph.D. by the Council of Scientific and Industrial Research (India).
  • 2011: Best talk by a graduate student (co-winner) at the 37th Midwest-Southeast Photosynthesis Meeting, Marshall IN (USA).
  • 2012: Student Research Achievement Award at the 56th Annual Biophysical Society Meeting, San Diego CA (USA).
  • 2018: Best talk by a post-doctoral researcher at The Hitchhiker’s Guide to the Biomolecular Galaxy: A Purdue Mini-symposium on Integrating Structure, Function, and Interactions of the Biomolecular Universe at Purdue University, West Lafayette IN, USA
  • 2018: Best short talk by a post-doctoral researcher at the Third Annual Life Sciences Postdoc Symposium at Purdue University, West Lafayette IN, USA
  • 2019: Biophysical Society travel award to present research at the 63rd Annual Biophysical Society Meeting, Baltimore MD (USA)

Links of Interest