Kortekaas Jeroen, Müller Shirley A, Ringler Philippe, Gregorini Marco, Weynants Vincent E, Rutten Lucy, Bos Martine P, Tommassen Jan
Department of Molecular Microbiology, Institute of Biomembranes, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.
Microbes Infect. 2006 Jul;8(8):2145-53. doi: 10.1016/j.micinf.2006.04.011. Epub 2006 May 24.
The iron-limitation-inducible protein FrpB of Neisseria meningitidis is an outer-membrane-localized siderophore receptor. Because of its abundance and its capacity to elicit bactericidal antibodies, it is considered a vaccine candidate. Bactericidal antibodies against FrpB are, however, type-specific. Hence, an FrpB-based vaccine should comprise several FrpB variants to be capable of providing broad protection. To facilitate the development of a meningococcal subunit vaccine, we have established a procedure to obtain large quantities of the protein in a native-like conformation. The protein was expressed without its signal sequence in Escherichia coli, where it accumulated in inclusion bodies. After in vitro folding, the protein was biochemically, biophysically and biologically characterised. Our results show that in vitro folded FrpB assembles into oligomers, presumably dimers, and that it induces high levels of bactericidal antibodies in laboratory animals.
脑膜炎奈瑟菌的铁限制诱导蛋白FrpB是一种定位于外膜的铁载体受体。由于其丰度以及引发杀菌性抗体的能力，它被认为是一种疫苗候选物。然而，针对FrpB的杀菌性抗体具有型特异性。因此，基于FrpB的疫苗应包含几种FrpB变体，以便能够提供广泛的保护。为了促进脑膜炎球菌亚单位疫苗的开发，我们建立了一种程序，以获得大量天然构象的该蛋白。该蛋白在没有信号序列的情况下在大肠杆菌中表达，在那里它积聚在包涵体中。体外折叠后，对该蛋白进行了生化、生物物理和生物学特性鉴定。我们的结果表明，体外折叠的FrpB组装成寡聚体，可能是二聚体，并且它在实验动物中诱导高水平的杀菌性抗体。
