IN VITRO EVALUATION OF ANTIFUNGAL POTENTIAL AND ELECTRON MICROSCOPIC STUDIES OF BACILLUS AMYLOLIQUEFACIENS AGAINST ASPERGILLUS SPECIES
Keywords:
Anti-Aspergillus, Bacillus amyloliquefaciens, Toxicity, Aspergillus species, Scanning electron microscopyAbstract
Objective: Bacteria are able to synthesize a wide range of metabolites with fungicidal properties. The present study focused on the in vitro evaluation of antifungal potential of amyloliquefaciens DSM-1067 against Aspergillus spp. and its electron microscopic studies.
Methods: An invitro evaluation of antifungal activity of bacterial secreted and cellular proteins was determined by microbroth dilution, disc diffusion and spore germination inhibition assays (SGIA). The cytotoxicity of these bacterial proteins was determined by hemolytic assay, and the effect of Bacillus amyloliquefaciens DSM 1067 lysate proteins on Aspergillus fumigatus was visualized by scanning electron microscopy (SEM).
Results: Bacillus amyloliquefaciens DSM-1067 lysates showed the highest activity by inhibiting the growth of A. fumigatus, A. flavus completely at a concentration of 31.25 µg/ml. In vitro toxicity experiments resulted that the lysate of B. amyloliquefaciens DSM-1067was non-toxic against human erythrocytes even at high concentrations. These findings thus emphasize its usefulness in the development of new antifungal therapies. SEM analysis demonstrated the in vitro inhibition of A. fumigatus growth by B. amyloliquefaciens DSM-1067cytosolic proteins leading to wrinkled hyphae, irregular branching patterns. It also showed disruption of conidiophores development. These cytological effects of B. amyloliquefaciens DSM-1067on the hyphal growth of A. fumigatus can explain its potent anti-Aspergillus activity.
Conclusion: The present investigation revealed that B. amyloliquefaciens DSM-1067 lysate protein can act as a potential candidate for exploration in the development of effective and non-toxic treatments against Aspergillus induced diseases. Its effect on the development of conidiophores and hyphal growth are studied in the present study.
Â
Downloads
References
Mowat E, Lang S, Williams C, McCulloch E, Jones B, Ramage G. Phase-dependent antifungal activity against Aspergillus fumigatus developing multicellular filamentous biofilms. J Antimicrob Chemother 2008;62:1281-4.
Michael A, Faller P, Peter G, Pappas, John R. Invasive fungal pathogens: current epidemiological trends. Clin Infect Dis 2006;43:S3-14.
Dagenais TR, Keller NP. Pathogenesis of Aspergillusfumigatusin Invasive Aspergillosis. Clin Microbiol Rev 2009;22(3):447.
Marr KA, Carter RA, Boeckh M, Martin P, Corey L. Invasive aspergillosis in allogeneic stem cell transplant recipients: changes in epidemiology and risk factors. Blood 2002;100:4358-66.
Wald A, Leisenring W, Van Burik JA, Bowden RA. Epidemiology of Aspergillus infections in a large cohort of patients undergoing bone marrow Transplantation. J Infect Dis 1997;175:1459-66.
Tekaia F, Latge JP. Aspergillus fumigatus: saprophyte or pathogen? Curr Opin Microbiol 2005;8:385-92.
Selitrennikoff CP. Antifungal proteins. Appl Environ Microbiol 2001;67(7):2883-94.
Yadav V, Mandhan R, Kumar M, Gupta J, Sharma GL. Characterization of the Escherichia coli antifungal protein PPEBL21. Int J Microbiol 2010: doi.org/10.1155/2010/196363. [Article in Press].
Yadav V, Mandhan R, Pasha Q, Pasha S, Katyal A, Chhillar AK, et al. An antifungal protein from E. coli. J Med Microbiol 2007;56:637-44.
Sumathi C, Jayashree S, Sekaran G. Screening of antifungal activity of pink pigmented bacteria isolated from freshwater fish Labeorohita. J Pharm Res 2011;4(12):4467-9.
Wong JH, Hao J, Cao Z, Qiao M, Xu H, Bai Y, et al. An antifungal protein from B. amyloliquefaciens. J Appl Microbiol 2008;105(6):1888-98.
Mounia YA, Noreddine K, Chaouche LD, Insaf B, Ali MK, Hélène C, et al. Antifungal activity and bioactive compounds produced by Bacillus mojavensis and Bacillus subtilis. Afr J Microbol Res 2014;8(6):476-84.
Zhang SM, Wang YX, Meng LQ, Li J, Zhao XY, Cao X, et al. Isolation and characterization of antifungal lipopeptides produced by endophytic Bacillus amyloliquefaciens TF28. Afr J Microbiol Res 2012;6(8):1747-55.
Smith PK, Krohn RI, Hermanson GT, Mallia AK, Gartner FH, Provenzano MD, et al. Measurement of protein using bicinchoninic acid. Anal Biochem Anal Biochem 1985;150:76-85.
Chhillar AK, Arya P, Mukhergee C, Gupta P, Yadav Y, Sharma AK, et al. Microwave-assisted synthesis of antimicrobial dihydropyridines tetradropyrimidin-2-ones: Novel compound against Aspergillosis. Bioorg Med Chem 2006;14:973-98.
Latoud C, Peypoux F, Michel G, Genet R, Morgat J. Interactions of antibiotics of the iturin group with human erythrocytes. Biochim Biophys Acta 1986;856:526-35.
Benitez LB, Velho RV, Lisboa MP, Medina LF, Brandelli A. Isolation and characterization of antifungal peptides produced by Bacillus amyloliquefaciens LBM5006. J Microbiol 2010;48(6):791-7.