title: Use of Pseudomonas putida EstA as an anchoring motif for display of a periplasmic enzyme on the surface of Escherichia coli.
abstract: The functional expression of proteins on the surface of bacteria has proven important for numerous biotechnological applications. In this report, we investigated the N-terminal fusion display of the periplasmic enzyme beta-lactamase (Bla) on the surface of Escherichia coli by using the translocator domain of the Pseudomonas putida outer membrane esterase (EstA), which is a member of the lipolytic autotransporter enzymes. To find out the transport function of a C-terminal domain of EstA, we generated a set of Bla-EstA fusion proteins containing N-terminally truncated derivatives of the EstA C-terminal domain. The surface exposure of the Bla moiety was verified by whole-cell immunoblots, protease accessibility, and fluorescence-activated cell sorting. The investigation of growth kinetics and host cell viability showed that the presence of the EstA translocator domain in the outer membrane neither inhibits cell growth nor affects cell viability. Furthermore, the surface-exposed Bla moiety was shown to be enzymatically active. These results demonstrate for the first time that the translocator domain of a lipolytic autotransporter enzyme is an effective anchoring motif for the functional display of heterologous passenger protein on the surface of E. coli. This investigation also provides a possible topological model of the EstA translocator domain, which might serve as a basis for the construction of fusion proteins containing heterologous passenger domains.
authors.affiliation: Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 373-1, Guseong-dong, Yuseong-gu, Daejeon 305-701, Republic of Korea.
authors.forename: Taek Ho
authors.initials: TH
authors.lastname: Yang
authors.forename: Jae Gu
authors.initials: JG
authors.lastname: Pan
authors.forename: Yeon Soo
authors.initials: YS
authors.lastname: Seo
authors.forename: Joon Shick
authors.initials: JS
authors.lastname: Rhee
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001709:Biotechnology / Q000379:methods; D002265:Carboxylic Ester Hydrolases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics; D008969:Molecular Sequence Data; D019897:Periplasm / Q000201:enzymology*; D016958:Pseudomonas putida / Q000201:enzymology* / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism*; D017422:Sequence Analysis, DNA; D001618:beta-Lactamases / Q000235:genetics / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D011993:Recombinant Fusion Proteins; D002265:Carboxylic Ester Hydrolases; C098953:EstA protein, bacteria; D001618:beta-Lactamases