title: Comparative analysis of twin-arginine (Tat)-dependent protein secretion of a heterologous model protein (GFP) in three different Gram-positive bacteria.
abstract: In contrast to the general protein secretion (Sec) system, the twin-arginine translocation (Tat) export pathway allows the translocation of proteins across the bacterial plasma membrane in a fully folded conformation. Due to this feature, the Tat pathway provides an attractive alternative to the secretory production of heterologous proteins via the Sec system. In this study, the potential for Tat-dependent heterologous protein secretion was compared in the three Gram-positive bacteria Staphylococcus carnosus, Bacillus subtilis, and Corynebacterium glutamicum using green fluorescent protein (GFP) as a model protein. In all three microorganisms, fusion of a Tat signal peptide to GFP resulted in its Tat-dependent translocation across the corresponding cytoplasmic membranes. However, striking differences with respect to the final localization and folding status of the exported GFP were observed. In S. carnosus, GFP was trapped entirely in the cell wall and not released into the supernatant. In B. subtilis, GFP was secreted into the supernatant, however, in an inactive form. In contrast, C. glutamicum effectively secreted active GFP. Our results clearly demonstrate that a comparative evaluation of different Gram-positive host microorganisms is a crucial step on the way to an efficient Tat-mediated secretory production process for a desired heterologous target protein.
authors: Institut für Biotechnologie 1, Forschungszentrum Jülich GmbH, 52425, Jülich, Germany.
authors: Daniel
authors: D
authors: Meissner
authors: Angela
authors: A
authors: Vollstedt
authors: Jan Maarten
authors: JM
authors: van Dijl
authors: Roland
authors: R
authors: Freudl
mesh_terms: D001412:Bacillus subtilis / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001693:Biological Transport, Active; D001709:Biotechnology; D048230:Corynebacterium glutamicum / Q000235:genetics / Q000378:metabolism; D005798:Genes, Bacterial; D006094:Gram-Positive Bacteria / Q000235:genetics / Q000378:metabolism*; D049452:Green Fluorescent Proteins / Q000096:biosynthesis / Q000235:genetics; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000235:genetics; D013045:Species Specificity; D013050:Spectrometry, Fluorescence; D013210:Staphylococcus / Q000235:genetics / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D026901:Membrane Transport Proteins; D011994:Recombinant Proteins; D049452:Green Fluorescent Proteins