A short synthetic signal peptide (SSSP) of 26 amino acid and a long one of
35 amino acids (LSSP), having an additional ribosome binding site (RBS), we
re synthesized. The SSSP sequence was based on the comparison of known effi
cient Streptomyces signal sequences. The SSSP and the LSSP were connected t
o the Streptomyces sp. TO1 amylase gene (amyTO1) without its signal peptide
. These constructions, when cloned into Streptomyces sp. TO1 and placed und
er the control of the ermE-up promoter of Saccharopolyspora erythrea, incre
ased the secretion of the amylase up to six-fold when compared to the natur
al amyTO1 signal peptide.