Qualification: 
MSc, BSc
​muralidharanv@am.amrita.edu

Muralidharan V. is currently pursuing his doctoral degree in Biotechnology at Amrita Agilent Analytical Research Centre, School of Biotechnology under the supervision of Dr. Sudarslal S. In addition to this, he also works as a research consultant to Amrita Centre for Research and Development. Before joining at School of Biotechnology, Muralidharan was working as a Junior Research Fellow at Amrita Centre for Nanoscience and Molecular Medicine. He completed his masters in Biotechnology from Amrita School of Biotechnology and holds a bachelors degree in Biotechnology and a diploma in Bioinstrumentation from Bharathiar University.

Awards / Honor

  • Awarded with Junior Research Fellowship from Amrita Vishwa Vidyapeetham.
  • Qualified GATE-Biotechnology, March 2012.

Research Interests and Expertise

  • Diabetes and Vascular Inflammation
  • Proteomics
  • Mass Spectrometry and High Performance Liquid Chromatography (HPLC) Techniques

Trainings and Workshops

  • Two month operator's training course for Agilent LC/MS: Agilent OpenLAB Chemstation, Agilent 1290 uHPLC, Agilent 6340 LC/MS Iontrap, Agilent 8354 UV-Visible Spectrometer, held at the Amrita Agilent Analytical Research Centre, Amrita School of Biotechnology from 5th August - 5th October,2013 headed by Dr.Walter Schrenk, Associate Professor, Amrita School of Biotechnology.
  • Development of Analytical methods in High Performance Chromatography, uHPLC, 2-Dimensional HPLC and Mass Spectrometry for the analysis, isolation and identification of active components out of plant extracts with potential medical uses under the guidance of Dr. Walter Schrenk and Dr.Sudarslal S, the Associate Professors at Amrita School of Biotechnology, from January to May 2014.

Research Projects

Publications

Publication Type: Journal Article

Year of Publication Title

2019

A. Choorakott Pushkaran, Vinod, V., Muralidharan Vanuopadath, Sudarslal S, Shantikumar V Nair, Vasudevan, A. Kumar, Dr. Raja Biswas, and Dr. Gopi Mohan C., “Combination of Repurposed Drug Diosmin with Amoxicillin-Clavulanic acid Causes Synergistic Inhibition of Mycobacterial Growth”, Scientific Reports, vol. 9, no. 1, 2019.[Abstract]


Effective therapeutic regimens for the treatment of tuberculosis (TB) are limited. They are comprised of multiple drugs that inhibit the essential cellular pathways in Mycobacterium tuberculosis (Mtb). The present study investigates an approach which enables a combination of Amoxicillin-Clavulanic acid (AMC) and a repurposed drug for its synergistic effect towards TB treatment. We identified Diosmin (DIO), by targeting the active site residues of L,D-transpeptidase (Ldt) enzymes involved in Mtb cell wall biosynthesis by using a structure-based drug design method. DIO is rapidly converted into aglycone form Diosmetin (DMT) after oral administration. Binding of DIO or DMT towards Ldt enzymes was studied using molecular docking and bioassay techniques. Combination of DIO (or DMT) and AMC exhibited higher mycobactericidal activity against Mycobacterium marinum as compared to individual drugs. Scanning electron microscopy study of M. marinum treated with AMC-DIO and AMC-DMT showed marked cellular leakage. M. marinum infected Drosophila melanogaster fly model showed an increased fly survival of 60% upon treatment with a combination of AMC and DIO (or DMT). Finally, the enhanced in vitro antimicrobial activity of AMC-DIO was validated against Mtb H37Ra and a MDR clinical isolate. Our results demonstrate the potential for AMC and DIO (or DMT) as a synergistic combination for the treatment of TB. © 2019, The Author(s).

More »»

2019

Divya Nair, Muralidharan Vanuopadath, Balasubramanian, A., Iyer, A., Ganesh, S., Anil, A. Nair, Vikraman, V., Pillai, P., Bose, C., Dr. Bipin G. Nair, Pai, J. Gopalakris, and Nair, S. Sadasivan, “Phlorotannins from Padina tetrastromatica: structural characterisation and functional studies”, Journal of Applied Phycology, pp. 1–11, 2019.[Abstract]


In this study, LC–MS/MS-based structural characterisation of phlorotannins from Padina tetrastromatica, a marine brown macroalga collected from South-West coastal region of Kerala, and its bioactivities are presented. The tandem mass spectrometric data revealed a series of phlorotannins with degree of polymerisation ranging from 2 to 18. The characteristic neutral loss of tandem mass spectra further confirmed that these molecules belong to fucophlorethol class of phlorotannins. DPPH assay of the HPLC-purified, phlorotannin-enriched fraction possesses significant free radical-scavenging activity. Cell viability assay indicated that phlorotannin concentration ranging from 1.5 to 50.0 μg mL−1 is non-toxic to THP-1 cell lines. Anti-inflammatory assay performed through gelatin zymography confirmed that phlorotannins ameliorated high-glucose-induced pro-MMP-9 expression in a dose-dependent manner whereas the level of pro-MMP-2 remains unaltered. The antimicrobial assays carried out using both the crude and HPLC-purified phlorotannin fraction showed its anti-MRSA potential.

More »»

2018

Muralidharan Vanuopadath, Nithin Sajeev, Athira Radhamony Murali, Nayana Sudish, Nithya Kangosseri, Ivy Rose Sebastian, Nidhi Dalpatraj Jain, Amit Pal, Dileepkumar Raveendran, Dr. Bipin G. Nair, and Sudarslal Sadasivan Nair, “Mass spectrometry-assisted venom profiling of Hypnale hypnale found in the Western Ghats of India incorporating de novo sequencing approaches.”, International Journal of Biological Macromolecules, vol. 118, no. Part B, pp. 1736-1746, 2018.[Abstract]


Hypnale hypnale (hump-nosed pit viper) is considered to be one among the medically important venomous snake species of India and Sri Lanka. In the present study, venom proteome profiling of a single Hypnale hypnale from Western Ghats of India was achieved using SDS-PAGE based protein separation followed by LC-MS/MS analysis. The identities of the proteins that were not established using the Mascot search were determined through de novo sequencing tools such as Novor followed by MS-BLAST based sequence similarity search algorithm and PEAKS proteomics software. The combined proteomics analysis revealed a total of 37 proteins belonging to nine different snake venom families, in which 7 proteins were exclusively identified through de novo strategies. The enzymatic and non-enzymatic venom protein families identified include serine proteases, metalloproteases, phospholipase A, thrombin-like enzymes, phospholipase B, C-type lectins/snaclecs, disintegrins, cysteine rich secretory proteins and nerve growth factor. Among these, disintegrins, nerve growth factor, phospholipase B and cysteine rich secretory protein families were identified for the first time in HPV venom. This could possibly explain the regiospecific venom variation seen across snake species. Taken together, the venom proteome profiling on Indian Hypnale hypnale venom correlates with the clinical manifestations often seen in the envenomed victims.

More »»

2018

Jayalekshmi H., Omanakuttan, A., Menon, N. D., Muralidharan Vanuopadath, Nair, S. Sadasivan, Corriden, R., Nair, B. G., Nizet, V., and Kumar, G. B., “Clove Bud Oil Modulates Pathogenicity Phenotypes of the Opportunistic Human Pathogen Pseudomonas aeruginosa.”, Sci Rep, vol. 8, no. 1, p. 3437, 2018.[Abstract]


Earlier studies from our laboratory have demonstrated that clove bud oil (CBO) attenuates expression of certain virulence factors of Pseudomonas aeruginosa PAO1. Here, we probe more deeply into the effect of CBO on four pseudomonal proteases - elastase A, elastase B, protease IV and alkaline protease - each known to play key roles in disease pathogenesis. CBO inhibited the activity of these proteases present in the bacterial culture supernatant. Zymography studies indicated that these proteases can activate host matrix metalloproteases (MMPs) to establish infection, through conversion of pro-MMP-2 to active MMP-2. PAO1 is a predominant pathogen in burn wound infections and we show the modulatory effect of CBO on MMPs in an in vitro model of burn injury. Furthermore, CBO induced dose-dependent neutrophil extracellular trap formation in human neutrophils. CBO also increased the survival of C. elegans infected with PAO1, establishing an anti-infective role in a whole animal model of pathogenesis. LC-MS/MS analysis indicated that CBO treatment elicited a significant reduction of signalling molecules (Acyl-Homoserine-Lactone) involved in quorum sensing regulation. Our observations demonstrate that CBO attenuates key virulence mechanisms of this important human pathogen, while concomitantly enhancing host innate immunomodulatory functions, with potential implications for topical therapy against antibiotic-resistant infections.

More »»

2017

M. Chatterjee, D'Morris, S., Paul, V., Warrier, S., Vasudevan, A. Kumar, Muralidharan Vanuopadath, Nair, S. Sadasivan, Dr. Bindhu Paul, Dr. Gopi Mohan C., and Dr. Raja Biswas, “Mechanistic Understanding of Phenyllactic Acid Mediated Inhibition of Quorum Sensing and Biofilm Development in Pseudomonas Aeruginosa”, Appl Microbiol Biotechnol, vol. 101, no. 22, pp. 8223-8236, 2017.[Abstract]


Pseudomonas aeruginosa depends on its quorum sensing (QS) system for its virulence factors' production and biofilm formation. Biofilms of P. aeruginosa on the surface of indwelling catheters are often resistant to antibiotic therapy. Alternative approaches that employ QS inhibitors alone or in combination with antibiotics are being developed to tackle P. aeruginosa infections. Here, we have studied the mechanism of action of 3-Phenyllactic acid (PLA), a QS inhibitory compound produced by Lactobacillus species, against P. aeruginosa PAO1. Our study revealed that PLA inhibited the expression of virulence factors such as pyocyanin, protease, and rhamnolipids that are involved in the biofilm formation of P. aeruginosa PAO1. Swarming motility, another important criterion for biofilm formation of P. aeruginosa PAO1, was also inhibited by PLA. Gene expression, mass spectrometric, functional complementation assays, and in silico data indicated that the quorum quenching and biofilm inhibitory activities of PLA are attributed to its ability to interact with P. aeruginosa QS receptors. PLA antagonistically binds to QS receptors RhlR and PqsR with a higher affinity than its cognate ligands N-butyryl-L-homoserine lactone (C-HSL) and 2-heptyl-3,4-dihydroxyquinoline (PQS; Pseudomonas quinolone signal). Using an in vivo intraperitoneal catheter-associated medaka fish infection model, we proved that PLA inhibited the initial attachment of P. aeruginosa PAO1 on implanted catheter tubes. Our in vitro and in vivo results revealed the potential of PLA as anti-biofilm compound against P. aeruginosa.

More »»

2016

P. Malvi, Chaube, B., Singh, S. Vikram, Mohammad, N., Pandey, V., Vijayakumar, M. Vavachan, Radhakrishnan, R. Meenatheri, Muralidharan Vanuopadath, Nair, S. Sadasivan, Nair, B. Gopalakris, and Bhat, M. Kumar, “Weight control interventions reverse diet-induced obesity impaired therapeutic response of melanoma to dacarbazine”, Cancer & Metabolism, vol. 4, no. 21, 2016.[Abstract]


BACKGROUND:
Obesity-related cellular, metabolic, and molecular alterations have been shown to increase cancer risk and tumor progression and are associated with poorer therapeutic outcome in cancer patients. However, the impact of obesity and weight-control interventions on the therapeutic response in melanoma is poorly understood.

METHODS:
High fat diet (HFD)-induced obese mouse model was used in this study to evaluate the outcome of dacarbazine (DTIC) therapy in melanoma. We employed LC-MS/MS to determine the quantity of the drug in tumor, and in various tissues. Unique in vitro approach was used to complement in vivo findings by culturing melanoma cells in either conditioned medium (CM) obtained from differentiated adipocytes or in serum collected from experimental mice.

RESULTS:
We report that diet-induced obesity impairs the outcome of DTIC therapy and reduces overall survival in tumor-bearing mice. We provide evidence that obesity restricts the accessibility of DTIC to tumor tissue. Critically, upon curtailing adiposity, accumulation and efficacy of DTIC is significantly improved. Moreover, using appropriate in vitro approaches, we show that melanoma cells exhibit a drug-resistant phenotype when cultured in serum collected from diet-induced obese mice or in CM collected from 3T3-L1 adipocytes. The impaired therapeutic response to DTIC in obese state is mediated by fatty acid synthase (FASN), caveolin-1 (Cav-1), and P-glycoprotein (P-gp). The response to DTIC and overall survival were improved upon employing weight control interventions in the tumor-bearing HFD-fed (obese) mice.

CONCLUSIONS:
This study indicates that obesity not only supports rapid melanoma progression but also impairs the outcome of chemotherapy, which can be improved upon employing weight control interventions. From clinically relevant point of view, our study exemplifies the importance of lifestyle interventions in the treatment of obesity-promoted cancers.

More »»
PDF iconweight-control-interventions-improve-therapeutic-efficacy-of-dacarbazine-in-melanoma-by-reversing-obesity-induced-drug-resistance-2016.pdf

2016

Muralidharan Vanuopadath, Divya Nair, Dr. Bipin G. Nair, and Sudarslal Sadasivan Nair, “Post-translational Modifications of Proteins: Biomarkers and Therapeutic Targets for Diabetes Related Complications”, Current Proteomics, vol. 13, no. 4, pp. 251-270, 2016.[Abstract]


Diabetes Mellitus is a chronic metabolic disorder that is often associated with various complications including micro- and macro- angiopathies. The increase in mortality rates associated with these complications is one among the major factors that compels to define proper therapeutic strategies. Protein signatures including their post-translational modifications that are modulated under various disease conditions enabled the biomarker discovery processes and thereby facilitate to predict and diagnose the disease onset at an earlier stage. The identification of the post-translationally modified proteins not only enabled the biomarker prediction associated with various disease conditions but also has a great impact in target based drug discovery process. Mass spectrometry based proteome profiling aided the identification and characterization of these site specific modifications that had a huge impact on various functional aspects in a biological context. In this review, we tried to compile and discuss the information available regarding some of the modified proteins with regard to deregulated glucose metabolism. Several commonly observed modifications including glycosylation, hydroxylation, phosphorylation, nitration, nitrosylation and carbonylation that seem to have a major role in the management of diabetes disorders are summarized. Moreover, the importance and impact of less explored post-translational modifications such as palmitoylation, carbamylation, deamidation and SUMOylation that are associated to diabetes related complications are described.

More »»

2016

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.

More »»

2015

Naoshad Mohammad, Shivendra Vikram Singh, Parmanand Malvi, Balkrishna Chaube, Dipti Athavale, Muralidharan Vanuopadath, Sudarslal Sadasivan Nair, Dr. Bipin G. Nair, and Manoj Kumar Bhat, “Strategy to enhance efficacy of doxorubicin in solid tumor cells by methyl-β-cyclodextrin: Involvement of p53 and Fas receptor ligand complex”, Scientific reports, vol. 5, 2015.[Abstract]


Doxorubicin (DOX) is one of the preferred drugs for treating breast and liver cancers. However, its clinical application is limited due to severe side effects and the accompanying drug resistance. In this context, we investigated the effect on therapeutic efficacy of DOX by cholesterol depleting agent methyl-β-cyclodextrin (MCD), and explored the involvement of p53. MCD sensitizes MCF-7 and Hepa1-6 cells to DOX, Combination of MCD and marginal dose of DOX reduces the cell viability, and promoted apoptosis through induction of pro-apoptotic protein, Bax, activation of caspase-8 and caspase-7, down regulation of anti-apoptotic protein Bcl-2 and finally promoting PARP cleavage. Mechanistically, sensitization to DOX by MCD was due to the induction of FasR/FasL pathway through p53 activation. Furthermore, inhibition of p53 by pharmacological inhibitor pifithrin-α (PFT-α) or its specific siRNA attenuated p53 function and down-regulated FasR/FasL, thereby preventing cell death. Animal experiments were performed using C57BL/6J mouse isografted with Hepa1-6 cells. Tumor growth was retarded and survival increased in mice administered MCD together with DOX to as compared to either agent alone. Collectively, these results suggest that MCD enhances the sensitivity to DOX for which wild type p53 is an important determinant.

More »»
PDF iconstrategy-enhance-efficacy-doxorubicin-solid-tumor-cells-methyl-cyclodextrin-involvement-of-p-53-and-fas-receptor-ligand-complex-01july2015.pdf

Publication Type: Conference Proceedings

Year of Publication Title

2014

Divya Nair, Muralidharan Vanuopadath, Dr. Bipin G. Nair, Jayashree G, and Sudarslal S, “Isolation and Characterisation of Lipopeptides from a Bacillus subtilis sp. Strain, a marime algal endophyte”, Fourth International Seminar on Sustainable Utilisation of Tropical Plant Biomass- Ayur informatics. pp. 89-91, 2014.

Contact

Muralidharan V.
Amrita Agilent Analytical Research Centre
School of Biotechnology
Amrita Vishwa Vidyapeetham (Amritapuri Campus)
Clappana P.O., Kollam, Kerala, India. 690525
Tel +91 (0)476-2803000 Extn:3126
Mail id: muralidharanv@am.amrita.edu