The fusion DNA fragment of the lactococcal extracellular protease USP45 signal peptide, passenger protein and SBC were expressed in Lactococcus lactis and Lactobacillus paracasei.

• 融合乳酸菌胞外蛋白酶USP45讯息胜肽、乘载蛋白及表层蛋白质静默基因C端123个胺基酸，表现于副乾酪乳杆菌或乳酸链球菌。