Sunday, May 4, 2008
2-40

Biomonitoring of biosurfactant production by cultivation of green fluorescent protein-marked Bacillus subtilis W1012

Luiz Carlos Martins das Neves1, Marina Ishii1, Carla Fernandes de Melo Souza1, Thereza Christina Vessoni Penna1, and Attilio Converti2. (1) Department of Biochemical and Pharmaceutical Technology, School of Pharmaceutical Sciences, University of São Paulo, Av. Prof. Lineu Prestes, 580, B.16, 05508-900, São Paulo, Brazil, São Paulo, Brazil, (2) Dipartimento di Ingegneria Chimica e di Processo, Università degli Studi di Genova, Opera Pia 15, I-16145, Genova, Italy

Biosurfactant production was investigated using two strains of Bacillus subtilis, one being a reference strain (B. subtilis 1012) and the other a recombinant of this (B. subtilis W1012) made able to produce the green fluorescent protein (GFP). The results of batch cultivations carried out at different initial levels of glucose in the presence of 10 g/L casein demonstrated that the reference strain was able to release higher levels of biosurfactants in the medium at G0 ≥ 5.0 g/L (Bmax = 84-110 mg/L). The recombinant strain exhibited interesting levels of biosurfactants (Bmax = 90-104 mg/L) only at higher glucose concentrations (G0 ≥ 20 g/L). Under these nutritional conditions, the fluorescence intensity linked to the production of GFP was shown to be associated with the cell concentration even after the achievement of the stationary phase. The ability of the genetically-modified strain to simultaneously overproduce biosurfactant and GFP even at low biomass concentration makes it an interesting candidate for use as a biological indicator to monitor cell viability either in bioremediation or oil recovery operations.

See more of Poster Session One
See more of General Submissions

See more of The 30th Symposium on Biotechnology for Fuels and Chemicals (May 4 -- 7, 2008)