[Gene cloning, expression and characterization of N-acylhomoserine lactonase from Bacillus subtilis SS6].

This study was aimed to obtain a quorum quenching N-acylhomoserine lactonase gene from Bacillus subtilis SS6 and to characterize the enzyme.We amplified N-acylhomoserine lactonase gene from B. subtilis SS6 by PCR methods. Gene aiiA(SS6) was cloned into the expression vector of pET28 (a) and transformed into Escherichia coli BL21. The activity of AiiA(SS6) on signal N-(3-Oxooctanoyl)-L-homoserine lactone was characterized by high performance liquid chromatography (HPLC).We successfully cloned an N-acylhomoserine lactonase gene from B. subtilis SS6 strain, namely aiiA(SS6) (GenBank: KP125494). The sequencing result showed that the length of aiiA(SS6) was 891 bp and the gene contained an Open Reading Frame encoding 297 amino acids. HPLC results showed that AiiA(SS6) was very active between 50 and 90 degrees C and the optimal pH was 7.6. Lineweaver-Burk treatment of the data yielded apparent K(m) and the V(max) was 0.998 mmol/L and 22.3 U/mg, respectively. Moreover, the relative activity of the enzyme remained 86% after storing at 4 degrees C for 3 months.Our findings will be helpful for further studies.