Biodesulfurization in biphasic systems containing organic solvents

Area of Science:

• Biotechnology and Biocatalysis
• Environmental Microbiology
• Biochemical Engineering

Background:

• Conventional biocatalysis often suffers from low productivity.
• Biphasic systems offer enhanced productivity and are suitable for solvent-tolerant microorganisms.
• Biodesulfurization is crucial for removing sulfur compounds from fuels.

Purpose of the Study:

• To construct a novel solvent-tolerant bacterium for efficient biodesulfurization.
• To evaluate the performance of the engineered bacterium in biphasic systems with organic solvents.
• To explore the potential of this biocatalyst for industrial applications.

Main Methods:

• Genetic engineering of Pseudomonas putida Idaho with the dszABCD gene cluster from Rhodococcus erythropolis XP.
• Construction of a solvent-tolerant desulfurizing bacterium, Pseudomonas putida A4.
• Performing biphasic reactions to test desulfurization of heterocyclic compounds in various organic solvents.

Main Results:

• Pseudomonas putida A4 exhibited a substrate range similar to Rhodococcus erythropolis XP.
• The bacterium degraded dibenzothiophene at a specific rate of 1.29 mM/g/h in 10% p-xylene.
• Effective degradation of dibenzothiophene was observed in the presence of multiple organic solvents at 10% concentration.

Conclusions:

• Engineered Pseudomonas putida A4 is a promising biocatalyst for biodesulfurization in biphasic systems.
• The study represents a significant advancement in developing efficient biodesulfurization processes using whole-cell biocatalysts.
• This approach holds potential for biotechnological applications involving toxic organic solvents.