Dr. Jayashree G. currently serves as Assistant Professor at the School of Biotechnology. She is interested in Protein Biochemistry and Biophysics.

She was awarded Ph. D. in Biochemistry from Mahatma Gandhi University, Kerala, following which she joined Prof. A. Surolia’s lab at the Molecular Biophysics Unit, Indian Institute of Science, Bangalore for her post doctoral studies. During the tenure, she was involved in the studies of lectins using Isothermal titration calorimetry (ITC) and surface plasmon resonance (SPR). After the successful completion of the project, she joined Prof. Sandhya Visweswariah at MRDG, Indian Institute of Science. In Prof. Sandhya’s lab, her main focus was on exploring novel proteins involved in cAMP signaling pathway of Mycobacterium smegmatis. It is at this time she received Ad Futura Slovene Human Resources Development and Scholarship Fund award for 2010-2011 to visit the National Institute of Chemistry, Ljubljana, Slovenia where she worked in the Laboratory for Molecular Biology and Nanobiotechnology.

Prior to joining MRDG, she was a scientist at the SIBB R &D centre at Kalamasserry, Cochin. 


  1. Ph. D. in Biochemistry, Mahatma Gandhi University, Kerala, India.
  2. M. Sc. in Biochemistry, School of Biosciences, Mahatma Gandhi University, India.
  3. B. Sc. In Chemistry, Mahatma Gandhi University, India.


  1. Qualified Graduate Aptitude Test in Engineering (GATE), 1996
  2. Postdoctoral Fellowship from the Department of Biotechnology, Govt.of India, 2001
  3. Recipient of Ad Futura Slovene Human Resources Development and Scholarship Fund for 2010-2011


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Publication Type: Journal Article

Year of Publication Title


Divya Nair, Muralidharan Vanuopadath, Dr. Jayashree G., Dr. Bipin G. Nair, and Sudarslal Sadasivan Nair, “Identification and characterization of a library of surfactins and fengycins from a marine endophytic Bacillus sp.”, Journal of basic microbiology, vol. 56, no. 11, pp. 1159–1172, 2016.[Abstract]

An endophytic bacterial strain from a marine green alga,Ulva lactuca, was isolated and identified by 16S rRNA gene sequencing method. The bacterial isolate was found to secrete two major families of cyclic depsilipopeptides, surfactins, and fengycins. Sequencing of the isolated lipopeptides was carried out using the MSndata obtained from an electrospray ionization (ESI) ion trap mass spectrometer coupled to an HPLC system. The assigned sequences were confirmed by a chemical derivatization approach involving esterification followed by mass spectrometric analysis. Distinction of leucine residues from isoleucine was established through a combined electron transfer dissociation-collision-induced dissociation (ETD-CID) method. The fengycins described in this study were found to cause significant delay of growth of two plants,Vigna radiata(mung bean) andOryza sativa(rice). To the best of our knowledge, this is the first study describing identification and characterization of cyclic peptides from an endophyticBacillus sp. isolated from marine algae.

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A. Banerjee, Adolph, R. S., Dr. Jayashree G., Kleinboelting, S., Emmerich, C., Steegborn, C., and Visweswariah, S. S., “A Universal Stress Protein (USP) in Mycobacteria binds cAMP”, Journal of Biological Chemistry, vol. 290, pp. 12731–12743, 2015.[Abstract]

Mycobacteria are endowed with rich and diverse machinery for the synthesis, utilization, and degradation of cAMP. The actions of cyclic nucleotides are generally mediated by binding of cAMP to conserved and well characterized cyclic nucleotide binding domains or structurally distinct cGMP-specific and -regulated cyclic nucleotide phosphodiesterase, adenylyl cyclase, and E. coli transcription factor FhlA (GAF) domain-containing proteins. Proteins with cyclic nucleotide binding and GAF domains can be identified in the genome of mycobacterial species, and some of them have been characterized. Here, we show that a significant fraction of intracellular cAMP is bound to protein in mycobacterial species, and by using affinity chromatography techniques, we identify specific universal stress proteins (USP) as abundantly expressed cAMP-binding proteins in slow growing as well as fast growing mycobacteria. We have characterized the biochemical and thermodynamic parameters for binding of cAMP, and we show that these USPs bind cAMP with a higher affinity than ATP, an established ligand for other USPs. We determined the structure of the USP MSMEG_3811 bound to cAMP, and we confirmed through structure-guided mutagenesis, the residues important for cAMP binding. This family of USPs is conserved in all mycobacteria, and we suggest that they serve as “sinks” for cAMP, making this second messenger available for downstream effectors as and when ATP levels are altered in the cell.

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R. Sharma, Zaveri, A., Dr. Jayashree G., Srinath, T., Varshney, U., and Visweswariah, S. S., “Paralogous cAMP Receptor Proteins in Mycobacterium smegmatis Show Biochemical and Functional Divergence”, Biochemistry, vol. 53, pp. 7765–7776, 2014.[Abstract]

The cyclic AMP receptor protein (CRP) family of transcription factors consists of global regulators of bacterial gene expression. Here, we identify two paralogous CRPs in the genome of Mycobacterium smegmatis that have 78% identical sequences and characterize them biochemically and functionally. The two proteins (MSMEG_0539 and MSMEG_6189) show differences in cAMP binding affinity, trypsin sensitivity, and binding to a CRP site that we have identified upstream of the msmeg_3781 gene. MSMEG_6189 binds to the CRP site readily in the absence of cAMP, while MSMEG_0539 binds in the presence of cAMP, albeit weakly. msmeg_6189 appears to be an essential gene, while the Δmsmeg_0539 strain was readily obtained. Using promoter–reporter constructs, we show that msmeg_3781 is regulated by CRP binding, and its transcription is repressed by MSMEG_6189. Our results are the first to characterize two paralogous and functional CRPs in a single bacterial genome. This gene duplication event has subsequently led to the evolution of two proteins whose biochemical differences translate to differential gene regulation, thus catering to the specific needs of the organism.

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A. Y. Joseph, Babu, V. S., Dev, S. S., Dr. Jayashree G., Harish, M., Rajesh, M. D., Anisha, S., and Mohankumar, C., “Rapid detection and characterization of chikungunya virus by RT-PCR in febrile patients from Kerala, India”, Indian Journal of Experimental Biology, vol. 46, pp. 573-578, 2008.[Abstract]

There has been a resurgence and prevalence of fever with symptoms of Chikungunya (CHIK) and increased death toll in Kerala, the southern-most state of India. The objective of this study was to develop a rapid detection method to determine the presence of CHIK- virus in the serum samples collected from febrile patients in Kerala, India. Serum specimens were analyzed for CHIK viral RNA by RT-PCR using primers specific for nsP1 and E1 genes. Five out of twenty clinical samples were positive for CHIK virus. The partial sequences of the E1 and nsP1 genes of the strain, IndKL01 were highly similar to the Reunion strains and the recently isolated Indian strains. A novel substitution, A148V, was detected in the E1 gene of the isolate, IndKL02. The detection procedure used in this study was simple, sensitive and rapid (less than 4 hr). This result suggests that CHIK viruses similar to the Reunion strains, which had resulted in high morbidity and mortality rates, may have caused the recent Chikungunya outbreak in India. The effect of the variant, E1-A148V, in the virulence and the rate of transmission of the virus deserves further investigation. More »»


Dr. Jayashree G., Gupta, G., Karthikeyan, T., Sinha, S., Kandiah, E., Gemma, E., Oscarson, S., and Surolia, A., “Isothermal titration calorimetric study defines the substrate binding residues of calreticulin”, Biochemical and Biophysical Research Communications, vol. 351, pp. 14 - 20, 2006.[Abstract]

Earlier we established using modeling studies the residues in calreticulin (CRT) important for sugar-binding (M. Kapoor, H. Srinivas, K. Eaazhisai, E. Gemma, L. Ellgaard, S. Oscarson, A. Helenius, A. Surolia, Interactions of substrate with calreticulin, an endoplasmic reticulum chaperone, J. Biol. Chem. 278 (8) (2003) 6194 -6200). Here, we discuss the relative roles of Trp-319, Asp-317, and Asp-160 for sugar-binding by using site-directed mutagenesis and isothermal titration calorimetry (ITC). Residues corresponding to Asp-160 and Asp-317 in CNX play important role towards sugar-binding. From the present study we demonstrate that the residue Asp-160 is not involved in sugar-binding, while Asp-317 plays a crucial role. Further, it is also validated that cation–π interactions of the sugar with Trp-319 dictate sugar-binding in CRT. This study not only defines further the binding site of CRT but also highlights its subtle differences with that of calnexin. More »»


A. Jeyaprakash, Dr. Jayashree G., Mahanta, S. K., Swaminathan, C. P., Sekar, K., Surolia, A., and Vijayan, M., “Structural basis for the energetics of jacalin-sugar interactions: promiscuity versus specificity”, Journal of Molecular Biology, vol. 347, pp. 181 - 188, 2005.[Abstract]

Jacalin, a tetrameric lectin, is one of the two lectins present in jackfruit (Artocarpus integrifolia) seeds. Its crystal structure revealed, for the first time, the occurrence of the β-prism I fold in lectins. The structure led to the elucidation of the crucial role of a new N terminus generated by post-translational proteolysis for the lectin's specificity for galactose. Subsequent X-ray studies on other carbohydrate complexes showed that the extended binding site of jacalin consisted of, in addition to the primary binding site, a hydrophobic secondary site A composed of aromatic residues and a secondary site B involved mainly in water-bridges. A recent investigation involving surface plasmon resonance and the X-ray analysis of a methyl-α-mannose complex, had led to a suggestion of promiscuity in the lectin's sugar specificity. To explore this suggestion further, detailed isothermal titration calorimetric studies on the interaction of galactose (Gal), mannose (Man), glucose (Glc), Me-α-Gal, Me-α-Man, Me-α-Glc and other mono- and oligosaccharides of biological relevance and crystallographic studies on the jacalin–Me-α-Glc complex and a new form of the jacalin–Me-α-Man complex, have been carried out. The binding affinity of Me-α-Man is 20 times weaker than that of Me-α-Gal. The corresponding number is 27, when the binding affinities of Gal and Me-α-Gal, and those of Man and Me-α-Man are compared. Glucose (Glc) shows no measurable binding, while the binding affinity of Me-α-Glc is slightly less than that of Me-α-Man. The available crystal structures of jacalin–sugar complexes provide a convincing explanation for the energetics of binding in terms of interactions at the primary binding site and secondary site A. The other sugars used in calorimetric studies show no detectable binding to jacalin. These results and other available evidence suggest that jacalin is specific to O-glycans and its affinity to N-glycans is extremely weak or non-existent and therefore of limited value in processes involving biological recognition. More »»


M. Kapoor, Ellgaard, L., Dr. Jayashree G., Schirra, C., Gemma, E., Oscarson, S., Helenius, A., and Surolia, A., “Mutational analysis provides molecular insight into the carbohydrate-binding region of calreticulin: pivotal roles of tyrosine-109 and aspartate-135 in carbohydrate recognition”, Biochemistry, vol. 43, pp. 97–106, 2004.[Abstract]

Calreticulin (CRT) is a lectin chaperone present in the lumen of the endoplasmic reticulum. It interacts with various glycoproteins by binding via their attached Glc1Man9GlcNAc2 moiety. To provide further insight into these lectin−glycan interactions, we are investigating the interaction of CRT with various sugars. We have earlier modeled the complex between CRT and the Glc1Man3 tetrasaccharide, a derivative of the native Glc1Man9GlcNAc2 sugar moiety. Here, we have systematically mutated the residues implicated by the model in the interaction of CRT to its sugar substrates and categorized the role played by each of the subsites of calreticulin toward the glycan binding. The CRT mutants Y109F and D135L did not show any binding to the sugar substrates interacting with the wild-type protein, demonstrating the great importance of these residues in the carbohydrate-binding site of CRT. Also, D317L and M131A showed weak affinity toward the trisaccharide. The mutation of residues from the primary binding site of CRT, i.e., those interacting with glucose, appears to be far less tolerated as compared to mutations in residues that interact with the mannose residues of the glycan. Also, methyl-2-deoxy-glucopyranosyl-α(1→3)-mannopyranoside failed to bind, asserting to the significance of the interactions between the primary binding site of CRT and the 2‘-OH of the glucose residue of the oligosaccharide substrate in generating specificity for this recognition. These studies provide detailed molecular insight into the sugar binding specificity of CRT. More »»


G. Vasundhara, Dr. Jayashree G., and G Kurup, M., “Sequestration of nickel and copper by Azotobacter chroococcum SB1”, Bulletin of Environmental Contamination and Toxicology, vol. 72, pp. 1122–1127, 2004.[Abstract]

Though nitrogen fixes are recommended as good bio fertizers, their efficiency in a polluted environment is a problem of great concers. In the present paper we have focused on one of the major pollutants, heavy metals viz nickel and copper and their toxicological effects on the nitrogen fixer, Azotobacter chroococcum; Nickel and copper are reported to be toxic inspite of their biological importance(Dalton et al, 1985). Some organisms are reported to accumulate heavy metals inspite of their toxicity(Fuchs, Thauer 1988; Maier et al, 1990) But no reports are available on the effects of nickel and copper on the nitrogen fixing capacity of Azotobacter sp. We have investigated the efficiency of nitrogen fixation and induction of thiols as a function of heavy metal binding peptides in A. Chroococcum. More »»


M. Kapoor, Dr. Jayashree G., Surolia, N., and Surolia, A., “Mutational analysis of the triclosan-binding region of enoyl-ACP (acyl-carrier protein) reductase from Plasmodium falciparum”, Biochemical Journal, vol. 381, pp. 735–741, 2004.[Abstract]

Triclosan, a known antibacterial, acts by inhibiting enoyl-ACP (acyl-carrier protein) reductase (ENR), a key enzyme of the type II fatty acid synthesis (FAS) system. Plasmodium falciparum, the human malaria-causing parasite, harbours the type II FAS; in contrast, its human host utilizes type I FAS. Due to this striking difference, ENR has emerged as an important target for the development of new antimalarials. Modelling studies, and the crystal structure of P. falciparum ENR, have highlighted the features of ternary complex formation between the enzyme, triclosan and NAD+ [Suguna, A. Surolia and N. Surolia (2001) Biochem. Biophys. Res. Commun. 283, 224–228; Perozzo, Kuo, Sidhu, Valiyaveettil, Bittman, Jacobs, Fidock, and Sacchettini (2002) J. Biol. Chem. 277, 13106–13114; and Swarnamukhi, Kapoor, N. Surolia, A. Surolia and Suguna (2003) PDB1UH5]. To address the issue of the importance of the residues involved in strong specific and stoichiometric binding of triclosan to P. falciparum ENR, we mutated the following residues: Ala-217, Asn-218, Met-281, and Phe-368. The affinity of all the mutants was reduced for triclosan as compared with the wild-type enzyme to different extents. The most significant mutation was A217V, which led to a greater than 7000-fold decrease in the binding affinity for triclosan as compared with wild-type PfENR. A217G showed only 10-fold reduction in the binding affinity. Thus, these studies point out significant differences in the triclosan-binding region of the P. falciparum enzyme from those of its bacterial counterparts. More »»


A. Mathew, Kurup, G. M., Dr. Jayashree G., Dr. Sudarslal S., and Vasundhara, G., “Antitumour Property of Vinblastine Monohydrazide”, Indian Journal of Pharmaceutical Sciences, vol. 66, pp. 117–120, 2004.[Abstract]

The bioconverted product of vinblastine (alkaloid from Vinca rosea), vinblastine monohydrazide was administered to cell line-induced solid tumour in mice and the changes in life span and tumour size were noted. It was found that the bioconverted product was an antitumour agent as it helps in the reduction of solid tumour and also in increasing the life span of tumour induced mice when compared to the crude alkaloid vinblastine.

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Dr. Jayashree G., Kurup, G. M., Dr. Sudarslal S., and Jacob, V. B., “Anti-oxidant activity of Centella asiatica on lymphoma-bearing mice”, Fitoterapia, vol. 74, pp. 431 - 434, 2003.[Abstract]

Oral treatment with 50 mg kg−1 day−1 of crude methanol extract of Centella asiatica for 14 days significantly increased the anti-oxidant enzymes, like superoxide dismutase (SOD), catalase and glutathione peroxidase (GSHPx), and anti-oxidants like glutathione (GSH) and ascorbic acid decreased in lymphoma-bearing mice.

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G. Vasundhara, Kurup, G. M., Dr. Jayashree G., Sethuraj, M. R., and Kothandaraman, R., “Nitrogen fixation in Lyngbya Sp under heavy metal stress”, Bulletin of Pure and Applied Sciences, vol. 21, pp. 37-51, 2002.