Kirimura K, Furuya T, Nishii Y, Ishii Y, Kino K, Usami S
Department of Applied Chemistry, School of Science and Engineering, Waseda University, 3-4-1 Ohkubo, Shinjuku-ku, Tokyo 169-8555, Japan.
J Biosci Bioeng. 2001;91(3):262-6. doi: 10.1263/jbb.91.262.
Heterocyclic organosulfur compounds such as dibenzothiophene (DBT) in petroleum cannot be completely removed by hydrodesulfurization using chemical catalysts. A moderately thermophilic bacterium Bacillus subtilis WU-S2B, which could desulfurize DBT at 50 degrees C through the selective cleavage of carbon-sulfur (CS) bonds, was newly isolated. At 50 degrees C, growing cells of WU-S2B could degrade 0.54 mM DBT within 120 h to produce 2-hydroxybiphenyl, and the resting cells could also degrade 0.81 mM DBT within 12 h. The DBT-desulfurizing ability of WU-S2B is high over a wide temperature range from 30 to 50 degrees C, and highest at 50 degrees C for both the growing and resting cells, and this is an extremely advantageous property for the practical biodesulfurization. In addition, WU-S2B could also desulfurize DBT derivatives such as 2,8-dimethylDBT, 4,6-dimethylDBT and 3,4-benzoDBT. Therefore, B. subtilis WU-S2B is considered to have more beneficial properties than other desulfurizing bacteria such as Rhodococcus strains previously reported, particularly from the viewpoint of its capacity for thermophilic desulfurization through the CS bond cleavage.
石油中的二苯并噻吩（DBT）等杂环有机硫化合物无法通过使用化学催化剂的加氢脱硫完全去除。新分离出一种中度嗜热细菌枯草芽孢杆菌WU-S2B，它可以在50℃通过选择性断裂碳-硫（C-S）键使DBT脱硫。在50℃时，WU-S2B的生长细胞能够在120小时内降解0.54 mM DBT以产生2-羟基联苯，静止细胞也能在12小时内降解0.81 mM DBT。WU-S2B的DBT脱硫能力在30至50℃的宽温度范围内都很高，对于生长细胞和静止细胞而言在50℃时最高，这对于实际生物脱硫来说是一个极其有利的特性。此外，WU-S2B还可以使DBT衍生物如2,8-二甲基DBT、4,6-二甲基DBT和3,4-苯并DBT脱硫。因此，枯草芽孢杆菌WU-S2B被认为比先前报道的其他脱硫细菌如红球菌菌株具有更有益的特性，特别是从其通过C-S键断裂进行嗜热脱硫的能力来看。
