Faculty & Staff

Purnananda Guptasarma
Professor
PhD (1993) CCMB, Hyderabad
Room No. 3F9
Sector 81
IISER Mohali

Phone: 0172-2293151
Email: guptasarma[at]iisermohali.ac.in


Purnananda Guptasarma

 

Research summary

 

I work in the areas of protein structural biochemistry, and protein engineering. Over the last two decades and more, I have been fascinated by three sets of questions in molecular and cellular biology : (i) How do proteins fold to native structure, become stable (or hyper-stable), and function  (especially as enzymes), OR misfold to undergo aggregation ? (ii) How is gene expression regulated by controlling the topological states of (and physical access of proteins to), either DNA or RNA ? (ii) How do the developmental fates of cells, during organismal development, become determined genetically even prior to the onset of zygotic gene expression, when cells lose totipotency under maternal genetic control? I have worked and published extensively in the first of the three areas above, and continue to do so, even as I approach the ‘three-quarters line’ of my second decade as a Principal Investigator. In the second of the areas above, I’ve published some theories and experiments, and have launched into many more, the results of which are not yet published. In the third area, I’ve done much thinking, but no experiments yet. As an experimentalist, I use every instrumentation-based tool or technique that I can get myself to learn, or master, given my background in both engineering and science before my Ph.D in molecular biophysics and biochemistry. Currently, I use all conceivable techniques in cellular and molecular biology and microscopy, as well as all forms of UV-Vis-IR spectroscopy, calorimetry, light  scattering,  surface  probing,  and  mass  spectrometry,  all  analytical  and  chromatographic  modes  of ultracentrifugation,   chromatography,   and   electrophoresis,   as   well   as   some   NMR,   ESR,   and   X-ray crystallography (the last three of these largely in collaborative mode). I also use molecular modeling.

 

Currently, three-fifths of the work in my lab is on ex-vivo studies of protein structure, stability, folding and   function,   or   misfolding   and   aggregation,   using   many   different   experimental   systems;   mostly hyperthermophile-derived proteins. The remaining two-fifths relate to studies of DNA-protein interactions or gene expression, or cellular responses to protein aggregates.

 

In recent years, we have discovered a novel fluorescence in proteins (from H-bonded peptide bonds); invented a new technique for grafting beta sheet-based active surfaces between proteins; unraveled the molecular mechanisms of high kinetic stability in hyperthermophile proteins (and used these to engineer proteins, to make them more or less kinetically stable, by design); discovered novel health implications and modes of aggregation of certain medically-relevant proteins; and developed new methods in fluorescence spectroscopy, mass spectrometry, gene expression and bioinformatics.

 

For more information about our lab and research please visit Guptasarma lab

 

Selected Publications

  • Kundu, B.  and Guptasarma, P. (1999). Hydrophobic dye inhibits the aggregation of molten carbonic anhydrase during thermal unfolding and refolding. Proteins : Structure, Function, Bioinformatics. 37, 321-324.
  • Shukla, A., Raje, M.  and Guptasarma, P. (2003). A backbone-reversed form of an all-beta alpha crystallin domain from a small heat-shock protein (retro-HSP12.6) folds and assembles into structured multimers. Journal of Biological Chemistry 278, 26505-26510.
  • Mukherjee, S., Sharma, S., Kumar, S. &Guptasarma P. (2005). Slow irreversible unfolding of Pyrococcus furiosus triosephosphate isomerase: separation and quantitation of conformers through a novel electrophoretic approach. Analytical Biochemistry 347, 49-59.
  • Sharma, S. &Guptasarma, P. (2008). Dimorphic aggregation behavior of a fusion polypeptide incorporating a stable protein domain (EGFP) with an amyloidogenic sequence (retro CspA). FEBS Letters 582, 2203-2211.
  • Ahmed, S., Kapoor. D., Singh, B. &Guptasarma, P. (2008). Conformational behavior of polypeptides derived through simultaneous global conservative site-directed mutagenesis of chymotrypsin inhibitor 2. Biochimica et Biophysica Acta : Proteins and Proteomics 1784, 796-805.
  • Chandrayan, S. K. &Guptasarma, P. (2009). Attenuation of ionic interactions profoundly lowers the kinetic thermal stability of Pyrococcus furiosus triosephosphate isomerase. Proteins : Structure, Function, Bioinformatics 72, 539-546.
  • Kapoor, D., Singh, B., Subramanian K. &Guptasarma, P. (2009) Creation of a new eye lens crystallin (Gambeta) through structure-guided mutagenic grafting of the surface of beta B2 crystallin onto the hydrophobic core of gamma B crystallin. FEBS Journal 276, 3341-3353.
  • Fatima,  U.,  Singh,  B.,  Subramanian,  K.  &Guptasarma  P.  (2012).  Insufficient  (sub-native)  helix  content  in soluble/solid  aggregates  of  recombinant  and  engineered  forms  of  IL-2  throws  light  on  how  aggregated  IL-2  is biologically active. Protein Journal. 31, 529-543.
  • Dhaunta, N., Arora, K., Chandrayan, S.K. &Guptasarma, P. (2013). Introduction of a thermophile-sourced ion pair network in the fourth beta/alpha unit of a psychophile-derived triosephosphate isomerase from Methanococcoides burtonii  significantly  increases  its  kinetic  thermal  stability.  Biochimica  et  Biophysica  Acta:  Proteins  and Proteomics. 1834:1023-1033.
  • Prakash, S., Sundd, M. &Guptasarma, P. (2014) The Key to the Extraordinary Thermal Stability of P. furiosus Holo- Rubredoxin: Iron Binding-Guided Packing of a Core Aromatic Cluster Responsible for High Kinetic Stability of the Native Structure. PLoS One 9, e89703.

Group

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