The striking effects of spacer and terminator sequences on the synthesis of porcine growth hormone inEscherichia coli

Abstract

Two types of expression vectors containing theP tac orP L promoters, synthetic ribosomalbinding sequences (RBS), and a transciptional terminator (rrnBT1T2) were constructed for the production of porcine growth hormone (pGH) inEscherichia coli. The results demonstrated that the nucleotide sequence between the RBS and the start codon, ATG, was critical for the yields of pGH. The rrnBT1T2 terminator was essential for the efficient expression ofpGH in theP tac -driven vectors, but reduced the synthesis of pGH in theP L -vectors. A leaky repression was observed in the JM103 cells containing theP tac -plasmids.