The faeA gene encoding a second feruloyl esterase from Aspergillus awamori has been cloned and characterized. The enzyme was higher expressed by using the novel pHsh expression vector than in pET vector in Echerichia coli. The site directed mutations changed codons for the first two arginines, a leucine and a proline in the 5' flanking region of faeA to CGU, CUG and CCG respectively, resulted in a maximum activity of 17.56 U/mg in pHsh system. The results of calculation using MFOLD showed the introduction of replacement of the nucleotides encoding the N-terminal region of the protein by optimizing rare codons based on reducing the mRNA secondary structures in TIR is a useful approach to increase the expression level of heterologous proteins in E. coli cells. The feruloyl esterase of Aspergillus awamori was clearly have different physicochemical characteristics and catalytic properties against cinnamoyl model substrates, such as methyl derivatives of hydroxycinnamic esters and soluble feruloylated oligosaccharides derived from plant cell wall. The enzyme acts synergistically in the degradation of the intricate structure of plant cell wall by hydrolyzing ferulate ester groups involved in the cross-linking between hemicelluloses and between hemicellulose and lignin

Extended Abstract Status: Not Uploaded