Biodesulfurization of Dibenzothiophene by a Newly Isolated Thermophilic Bacteria Strain

Document Type: Research Note


1 Department of Chemical and petroleum Engineering, Sharif University of Technology, Tehran, I.R. IRAN

2 Iranian Central Oil Fields Company (ICOFC), Tehran, I. R. IRAN


Microbiological analyses of soil chronically exposed to petroleum complex compounds of some oil springs in south of Iran resulted in isolation and purification of a new native thermophilic strain which is capable to desulfurize petroleum sulfur compounds by 4-S mechanism. Dibenzothiophene (DBT) was selected as a complex sulfur compound model and many experiments were done to identify the metabolic pathway. The results of these experiments show that DBT is ultimately converted to 2-hydroxybiphenyl (2-HBP) and sulfite. This is a special metabolic pathway in that there is no effect on the carbon skeleton of organic compounds and would be ideal for desulfurization to upgrade the petroleum products because it keeps the remaining hydrocarbon molecules fully active as energy sources without any loss of their thermal units. At the next step, some physical and chemical properties of main culture were optimized as follows: 6gr/lit glucose, 4gr/lit ammonium chloride, 0.15 mM DBT, pH= 7 and temperature= 45°C. During 6 days, growing cells of this microorganism can convert 87.5% of DBT in 250 ml flask. At last, kinetic analysis has been done and Michaelis-Menten equation qualified. Equation parameters Vmax and KM calculated and data led to 0.548 mM h−1 and 0.458 mM, respectively.


Main Subjects

[1] Samir Abbad-Andaloussi, Claire Lagnel, Michel Warzywoda, Frédéric Monot, Multi-criteria comparison of resting cell activities of bacterial strains selected for biodesulfurization of petroleum compounds, Enzyme and Microbial Technology, 32, p. 446 (2003).

[2] Sylvie Le Borgne,  Rodolfo  Quintero, Bio-technological processes for the Refining of petroleum, Fuel Processing Technology, 81, p.155 (2003).

[3] Christopher Oldfield, Olga Pogrebinsky, Julie Simmonds, Edwin S. Olson, Charles F. Kulpa, Elucidation of the metabolic pathway for dibenzothiophene desulphurization by Rhodococcus sp. strain IGTS8 (ATCC 53968), Microbiology, 143, p. 2961 (1997).

[4] Oshiro, T., Suzuki, K., Izumi, Y., Regulation of dibenzothiophene degrading enzyme activity of  Rhodococcus erythropolis D-1, Journal of fermentation and bioengineering, 81 (2), p. 121 (1996).

[5] Li, M.Z., Squires, C.H., Monticello, D.J., Childs, J.D., Genetic analysis of the dsz promoter and associated regulatory regions of Rhodococcus erythropolis IGTS8, J. of Bacteriol., p. 6409 (1996).

[6] Piddington, C.S., Kovacevich, B.R., Rambosek, J., Sequence and molecular characterization of a DNA region encoding the dibenzothiophene desulfuri-zation operon of Rhodococcus sp. strain IGTS8, Appl. Environ. Microbiol., 61 (2), p. 468 (1995).

[7] Yoshikawa, O., Ishi, Y., Koizumi, K., Ohshiro, T., Izumi, Y., Maruhashi, K., Enhancement and stabilization of desulfurization activity of Rhodococcus erythropolis KA2-5-1 by feeding ethanol and sulfur components, J. of Bioscience and  Bioengineering, 94 (5), p. 447 (2002).

[8] Yan, H., Kishimoto, M., Omasa, T., Katakore, Y., Suga, K. I., Okumura, K., Yoshikawa, O., Increase in desulfurization activity of Rhodococcus erythro-polis KA2-5-1 using ethanol feeding, J. of Bioscience  and bioengineering, 89 (4), p. 361 (2000).

[9] Okada, H., Nomura, N., Nakahara, T., Maruhashi, K., Analysis of substrate specificity of the desulfurizing bacterium mycobacterium sp. G3, J. of Bioscience and Bioengineering, 93 (2), p. 228 (2002).

[10] Maghsoudi, S., Vossoughi, M., Kheirolomoom, A., Emiko Tanaka, Shigeo Katoh, Biodesulfurization of hydrocarbons and diesel fuels by Rhodococcus sp. strain P32C1, Biochemical Engineering Journal, 8, p. 151 (2001).

[11] Kirimura, K., Furuya, T., Nishi, Y., Ishii, Y., Kino, K., Usami, S., Biodesulfurization of Dibenzo-thiophene and its derivatives through the selective cleavage of carbon-sulfur bonds by a moderately thermophilic bacterium bacillus subtilis WU-S2B, J. of Bioscience and Bioengineering, 91 (3), p. 262 (2001).

[12] Toshiki Furuya, Kohtaro Kirimura , Kuniki Kino, Shoji Usami, Thermophilic biodesulfurization of dibenzothiophene and its derivatives by Mycobacterium phlei WU-F1, FEMS Microbiology Letters, 204, p. 129 (2001).

[13] Jin Konishi, Yoshitaka Ishi, Toshimitsu Onaka, Koichi Okumura, Masanori Suzuki, Thermophilic carbon-sulfur-bond targeted biodesulfurization, Applied and Environmental Microbiology, 63 (8), p. 3164 (1997).

[14] Ishii, Y., Konishi, J., Okada, H., Hirasawa, K., Onaka, T., Suzuki, M." Operon structure and functional analysis of the genes encoding thermophilic desulfurizing enzymes of Paenibacillus sp. All-2., Biochem. Biophys. Res. Commun., 270, p. 81 (2000).

[15] Maghsoudi, S., Kheirolomoom, A., Vossoughi, M., Tanaka, E., Katoh, S., Selective desulfurization of dibenzothiophene by newly isolated Corynebac-terium sp. strain P32C1, Biochemical engineering journal, 5, p. 11 (2000).

[16] Daniel J. Monticello, Biodesulfurization and the upgrading of petroleum distillates, Current Opinion in Microbiology, 11, p. 540 (2000).

[17] Morio, K., Keizo, H., Yoshikawa, O., Hirasawa, K., Ishii, Y., Fujino, K., Sugiyama, H., Maruhashi, K., Kinetic analysis of microbial desulfurization of model and light gas oils containing multiple alkyl dibenzothiophenes, Biosci. Biotechnol. Biochem., 65, p. 298 (2001).

[18] Luo, M.F., Xing, J.M., Gou, Z.X., Li, S., Liu, H.Z., Chen, J.Y., Desulfurization of dibenzothiophene by lyophilized cells of Pseudomonas delafieldii R-8 in the presence of dodecane, Biochemical Engineering Journal, 13, p. 1 (2003).