Introduction: Alkanes are biodegraded to generate the corresponding primary alcohol troughalkane hydroxylases (AHs) consisting on an integral membrane alkane monooxygenase (AlkB)and two soluble proteins, rubredoxin and rubredoxin reductase. Recently, an alkB gene wasreported to be involved in degradation of long chain n-alkanes in the actinobacterium Gordoniasp. SoCg. This gene was expressed in Streptomyces coelicolor M145 which is unable todegrade n-alkanes.Results: The engineered strain, M145-AH, can biotransform n-hexadecane into thecorresponding 1-hexadecanol and it is able to grow on n-hexadecane as sole carbon source.Changes in global protein expression associated with n-hexadecane metabolism in M145-AHwere studied using a differential proteomic approach. M145-AH was incubated in three differentconditions using a mineral medium supplemented with hexadecane or glucose as the solecarbon source or without any carbon source, respectively. Total proteins, extracted fromsamples collected after 6, 24 and 48 h of incubation in the three conditions, were analyzed by2D-Differential Gel Electrophoresis (2D-DIGE). Differentially abundant protein spots wereidentified by mass spectrometry. The expression profile of proteins involved in central carbonmetabolism, amino acid and protein biosynthesis, fatty acid metabolism and respiration revealeda gradual metabolic adaptation to n-hexadecane utilization, which is similar to that of specializedalkane-degraders.Conclusion: Thus, the addition of the alkB gene confers to Streptomyces coelicolor the abilityto use an insoluble recalcitrant contaminant as an usual carbon source. These data, expandingthe knowledge on n-alkane bioconversion mechanisms in Gram-positive bacteria, provide newtechnological platforms for bioremediation studies and strategies.
|Number of pages||1|
|Publication status||Published - 2011|