Expression byStreptomyces lividansof the RatαIntegrin CD11b A-Domain as a Secreted and Soluble Recombinant Protein

[摘要] We already reported the use of a long synthetic signal peptide (LSSP) to secrete theStreptomycessp. TO1 amylase byStreptomyces lividansstrain. We herein report the expression and secretion of the rat CD11b A-domain using the same LSSP andS. lividansas host strain. We have used theEscherichia coli/Streptomycesshuttle vector pIJ699 for the cloning of the A-domain DNA sequence downstream of LSSP and under the control of the constitutiveermE-uppromoter ofStreptomyces erythraeus. Using this construct andS. lividansas a host strain, we achieved the expression of 8 mg/L of soluble secreted recombinant form of the A-domain of the rat leukocyteβ2 integrin CD11/CD18 alpha M subunit (CD11b). This secreted recombinant CD11b A-domain reacted with a function blocking antibody showing that this protein is properly folded and probably functional. These data support the capability ofStreptomycesto produce heterologous recombinant proteins as soluble secreted form using the “LSSP” synthetic signal peptide.

[学科分类] 基础医学