title: Protein Secretion in Gram-Positive Bacteria: From Multiple Pathways to Biotechnology.
abstract: A number of Gram-positive bacteria are important players in industry as producers of a diverse array of economically interesting metabolites and proteins. As discussed in this overview, several Gram-positive bacteria are valuable hosts for the production of heterologous proteins. In contrast to Gram-negative bacteria, proteins secreted by Gram-positive bacteria are released into the culture medium where conditions for correct folding are more appropriate, thus facilitating the isolation and purification of active proteins. Although seven different protein secretion pathways have been identified in Gram-positive bacteria, the majority of heterologous proteins are produced via the general secretion or Sec pathway. Not all proteins are equally well secreted, because heterologous protein production often faces bottlenecks including hampered secretion, susceptibility to proteases, secretion stress, and metabolic burden. These bottlenecks are associated with reduced yields leading to non-marketable products. In this chapter, besides a general overview of the different protein secretion pathways, possible hurdles that may hinder efficient protein secretion are described and attempts to improve yield are discussed including modification of components of the Sec pathway. Attention is also paid to omics-based approaches that may offer a more rational approach to optimize production of heterologous proteins.
authors.affiliation: Laboratory of Molecular Bacteriology, Department of Microbiology, and Immunology, KU Leuven, Rega Institute for Medical Research, 3000, Leuven, Belgium. jozef.anne@kuleuven.be.
authors.forename: Jozef
authors.initials: J
authors.lastname: Anné
authors.affiliation: Laboratory of Molecular Bacteriology, Department of Microbiology, and Immunology, KU Leuven, Rega Institute for Medical Research, 3000, Leuven, Belgium.
authors.forename: Anastassios
authors.initials: A
authors.lastname: Economou
authors.affiliation: Bio- & Chemical Systems Technology, Reactor Engineering and Safety Section, Department of Chemical Engineering, KU Leuven, Celestijnenlaan 200F, 3001, Leuven, Belgium.
authors.forename: Kristel
authors.initials: K
authors.lastname: Bernaerts
mesh_terms: D001426:Bacterial Proteins / Q000096:biosynthesis / Q000378:metabolism*; D001709:Biotechnology; D005285:Fermentation; D006094:Gram-Positive Bacteria / Q000378:metabolism*; D000069319:Type IV Secretion Systems / Q000502:physiology; D000069377:Type VII Secretion Systems / Q000502:physiology
chemical_list: D001426:Bacterial Proteins; D000069319:Type IV Secretion Systems; D000069377:Type VII Secretion Systems