Potent Chitin Synthase Inhibitors from Plants

Author(s): Amrutha Vijayakumar, Ajith Madhavan*, Chinchu Bose, Pandurangan Nanjan, Sindhu S. Kokkal, Archana P. Veedu, Megha Prasad, Sanjay Pal, Bipin G. Nair

Journal Name: Current Bioactive Compounds

Volume 16 , Issue 1 , 2020

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Abstract:

Background: Chitin is the main component of fungal, protozoan and helminth cell wall. They help to maintain the structural and functional characteristics of these organisms. The chitin wall is dynamic and is repaired, rearranged and synthesized as the cells develop. Active synthesis can be noticed during cytokinesis, laying of primary septum, maintenance of lateral cell wall integrity and hyphal tip growth. Chitin synthesis involves coordinated action of two enzymes namely, chitin synthase (that lays new cell wall) and chitinase (that removes the older ones). Since chitin synthase is conserved in different eukaryotic microorganisms that can be a ‘soft target’ for inhibition with small molecules. When chitin synthase is inhibited, it leads to the loss of viability of cells owing to the self- disruption of the cell wall by existing chitinase.

Methods: In the described study, small molecules from plant sources were screened for their ability to interfere with hyphal tip growth, by employing Hyphal Tip Burst assay (HTB). Aspergillus niger was used as the model organism. The specific role of these small molecules in interfering with chitin synthesis was established with an in-vitro method. The enzyme required was isolated from Aspergillus niger and its activity was deduced through a novel method involving non-radioactively labelled substrate. The activity of the potential lead molecules were also checked against Candida albicans and Caenorhabditis elegans. The latter was adopted as a surrogate for the pathogenic helminths as it shares similarity with regard to cell wall structure and biochemistry. Moreover, it is widely studied and the methodologies are well established.

Results: Out of the 11 compounds and extracts screened, 8 were found to be prospective. They were also found to be effective against Candida albicans and Caenorhabditis elegans.

Conclusion: Purified Methyl Ethyl Ketone (MEK) Fraction1 (F1) of Coconut (Cocos nucifera) Shell Extract (COSE) was found to be more effective against Candida albicans with an IC50 value of 3.04 μg/mL and on L4 stage of Caenorhabditis elegans with an IC50 of 77.8 μg/mL.

Keywords: Chitin synthase, Chitin, Hyphal Tip Burst (HTB) assay, Aspergillus niger, Candida albicans, Caenorhabditis elegans.

[1]
Johnston, W.L.; Dennis, J.W. The eggshell in the C. elegans oocyte-to-embryo transition. Genesis, 2012, (50), 333-349.
[2]
Rogers, R.A. A study of eggs of Ascaris lumbricoides var. suum with the electron microscope. J. Parasitol., 1956, 42(2), 97-108.
[http://dx.doi.org/10.2307/3274720] [PMID: 13320250]
[3]
Chaudhary, P.M.; Tupe, S.G.; Deshpande, M.V. Chitin synthase inhibitors as antifungal agents. Mini Rev. Med. Chem., 2013, 13(2), 222-236.
[PMID: 22512590]
[4]
Bartnicki Garcia, S.; Lippman, E. The bursting tendency of hyphal tips of fungi: Presumptive evidence for a delicate balance between wall synthesis and wall lysis in apical growth. J. Gen. Microbiol., 1972, 73(3), 487-500.
[http://dx.doi.org/10.1099/00221287-73-3-487] [PMID: 4567224]
[5]
Dow, J.M.; Rubery, P.H. Hyphal tip bursting in Mucor rouxii: Antagonistic effects of calcium ions and acid. J. Gen. Microbiol., 1975, 91(2), 425-428.
[http://dx.doi.org/10.1099/00221287-91-2-425] [PMID: 1464]
[6]
Jesus, J.A.; Lago, J.H.G.; Laurenti, M.D.; Yamamoto, E.S.; Passero, L.F.D. Antimicrobial activity of oleanolic and ursolic acids: an update. Evid. Based Complement. Alternat. Med., 2015, 1-14.
[7]
Kang, M.S.; Elango, N.; Mattia, E.; Au-Young, J.; Robbins, P.W.; Cabib, E. Isolation of chitin synthetase from Saccharomyces cerevisiae. Purification of an enzyme by entrapment in the reaction product. J. Biol. Chem., 1984, 259(23), 14966-14972.
[PMID: 6238967]
[8]
Kumirska, J.; Czerwicka, M.; Kaczyński, Z.; Bychowska, A.; Brzozowski, K.; Thöming, J.; Stepnowski, P. Application of spectroscopic methods for structural analysis of chitin and chitosan. Mar. Drugs, 2010, 8(5), 1567-1636.
[http://dx.doi.org/10.3390/md8051567] [PMID: 20559489]
[9]
Punithavathy, P.M.; Nalina, K.; Menon, T. Antifungal susceptibility testing of Candida tropicalis biofilms against fluconazole using calorimetric indicator resazurin. Indian J. Pathol. Microbiol., 2012, 55(1), 72-74.
[http://dx.doi.org/10.4103/0377-4929.94861] [PMID: 22499305]
[10]
Lucien, G.; Hebraud, M.; Vincent, G.; Fevre, M. Chitin synthase activity from neocallimastix frontalis, an anaerobic Rumen Fungus. J. Gen. Microbiol., 1989, 279-283.
[11]
Pettit, R.K.; Weber, C.A.; Kean, M.J.; Hoffmann, H.; Pettit, G.R.; Tan, R.; Franks, K.S.; Horton, M.L. Microplate Alamar blue assay for Staphylococcus epidermidis biofilm susceptibility testing. Antimicrob. Agents Chemother., 2005, 49(7), 2612-2617.
[http://dx.doi.org/10.1128/AAC.49.7.2612-2617.2005] [PMID: 15980327]
[12]
Marcelo, M.N.; Assaf, S.; Petros, B.; Carlo, R. A novel one-step, highly sensitive fluorometric assay to evaluate cell-mediated cytotoxicity. J. Immunol. Methods, 1998, 157-167.
[13]
Stiernagle, T. Maintenance of C. elegans, The C. elegans Research Community, Worm Book; Caenorhabditis Genetics Center, University of Minnesota: Minneapolis, USA, 2006.


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Article Details

VOLUME: 16
ISSUE: 1
Year: 2020
Page: [58 - 63]
Pages: 6
DOI: 10.2174/1573407213666180719145831
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