Metabolic and process engineering for biodesulfurization in Gram-negative bacteria

•Biodesulfurization is a real technology to reduce sulfur levels in fuel.•Metabolic and genetic engineering can overcome the major bottlenecks of the process.•Gram-negative bacteria are suitable hosts for engineering desulfurizing biocatalysts.•More efforts in process engineering are needed for the...

Full description

Saved in:
Bibliographic Details
Published in:Journal of biotechnology 2017-11, Vol.262, p.47-55
Main Authors: Martínez, I., El-Said Mohamed, M., Santos, V.E., García, J.L., García-Ochoa, F., Díaz, E.
Format: Article
Language:English
Subjects:
Biodegradation, Environmental
Biodesulfurization
Dibenzothiophene
Fossil Fuels - microbiology
Genetic engineering
Gram-negative bacteria
Gram-Negative Bacteria - enzymology
Gram-Negative Bacteria - genetics
Gram-Negative Bacteria - metabolism
Kinetics
Metabolic Engineering
Metabolic Networks and Pathways - genetics
Operon
Pseudomonas - genetics
Pseudomonas - metabolism
Scale-up
Sulfur Compounds - chemistry
Sulfur Compounds - metabolism
Thiophenes - metabolism
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:•Biodesulfurization is a real technology to reduce sulfur levels in fuel.•Metabolic and genetic engineering can overcome the major bottlenecks of the process.•Gram-negative bacteria are suitable hosts for engineering desulfurizing biocatalysts.•More efforts in process engineering are needed for the industrial application. Microbial desulfurization or biodesulfurization (BDS) is an attractive low-cost and environmentally friendly complementary technology to the hydrotreating chemical process based on the potential of certain bacteria to specifically remove sulfur from S-heterocyclic compounds of crude fuels that are recalcitrant to the chemical treatments. The 4S or Dsz sulfur specific pathway for dibenzothiophene (DBT) and alkyl-substituted DBTs, widely used as model S-heterocyclic compounds, has been extensively studied at the physiological, biochemical and genetic levels mainly in Gram-positive bacteria. Nevertheless, several Gram-negative bacteria have been also used in BDS because they are endowed with some properties, e.g., broad metabolic versatility and easy genetic and genomic manipulation, that make them suitable chassis for systems metabolic engineering strategies. A high number of recombinant bacteria, many of which are Pseudomonas strains, have been constructed to overcome the major bottlenecks of the desulfurization process, i.e., expression of the dsz operon, activity of the Dsz enzymes, retro-inhibition of the Dsz pathway, availability of reducing power, uptake-secretion of substrate and intermediates, tolerance to organic solvents and metals, and other host-specific limitations. However, to attain a BDS process with industrial applicability, it is necessary to apply all the knowledge and advances achieved at the genetic and metabolic levels to the process engineering level, i.e., kinetic modelling, scale-up of biphasic systems, enhancing mass transfer rates, biocatalyst separation, etc. The production of high-added value products derived from the organosulfur material present in oil can be regarded also as an economically viable process that has barely begun to be explored.
ISSN:0168-1656
1873-4863
DOI:10.1016/j.jbiotec.2017.09.004