A bacterium strain Z5,which can degrade 2-methylisoborneol efficiently,was isolated from sewage samples collected from the sewage treatment plant of Wuhan.This strain was identified as Enterobacter cloacae via the analysis of 16S rDNA.The results of the sole carbon source assay demonstrated that this stain was able to metabolize 2-MIB and the degradation rate was up to 89.7% determined by GC-MS.The growth of E.cloacae Z5 in 2-MIB at different concentrations were also determined and the growth curve in 16 μg/L 2-MIB was found to be as good as that in LB.To clone the gene coding for the key enzyme catalyzing the degradation of 2-MIB and to further investigate the degradation pathway,the global genome BAC library of E.cloacae Z5 was constructed.There were 810 clones in the library.The average size of inserts and the genome coverage was 40 kb and about 8-folds,respectively.