title: pspA overexpression in Streptomyces lividans improves both Sec- and Tat-dependent protein secretion.
abstract: Streptomyces is an interesting host for the secretory production of recombinant proteins because of its innate capacity to secrete proteins at high level in the culture medium. In this report, we evaluated the importance of the phage-shock protein A (PspA) homologue on the protein secretion yield in Streptomyces lividans. The PspA protein is supposed to play a role in the maintenance of the proton motive force (PMF). As the PMF is an energy source for both Sec- and Tat-dependent secretion, we evaluated the influence of the PspA protein on both pathways by modulating the pspA expression. Results indicated that pspA overexpression can improve the Tat-dependent protein secretion as illustrated for the Tat-dependent xylanase C and enhanced green fluorescent protein (EGFP). The effect on Sec-dependent secretion was less pronounced and appeared to be protein dependent as evidenced by the increase in subtilisin inhibitor (Sti-1) secretion but the lack of increase in human tumour necrosis factor (hTNFalpha) secretion in a pspA-overexpressing strain.
authors.affiliation: Laboratory of Bacteriology, Rega Institute for Medical Research, Katholieke Universiteit Leuven, Minderbroedersstraat 10, 3000, Leuven, Belgium.
authors.forename: Kristof
authors.initials: K
authors.lastname: Vrancken
authors.forename: Sophie
authors.initials: S
authors.lastname: De Keersmaeker
authors.forename: Nick
authors.initials: N
authors.lastname: Geukens
authors.forename: Elke
authors.initials: E
authors.lastname: Lammertyn
authors.forename: Jozef
authors.initials: J
authors.lastname: Anné
authors.forename: Lieve
authors.initials: L
authors.lastname: Van Mellaert
mesh_terms: D001426:Bacterial Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D043364:Endo-1,4-beta Xylanases / Q000235:genetics*; D049452:Green Fluorescent Proteins / Q000235:genetics; D006360:Heat-Shock Proteins / Q000096:biosynthesis* / Q000235:genetics; D006801:Humans; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism*; D048170:Streptomyces lividans / Q000235:genetics* / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D006360:Heat-Shock Proteins; D011993:Recombinant Fusion Proteins; D014409:Tumor Necrosis Factor-alpha; C485184:enhanced green fluorescent protein; C069816:phage shock protein, Bacteria; C072838:Streptomyces trypsin inhibitor 1 protein, Streptomyces; D049452:Green Fluorescent Proteins; D043364:Endo-1,4-beta Xylanases