The "seventeen kilodalton protein" (Skp) is a predominant periplasmic chaperone of Escherichia coli, which is involved in the biogenesis of abundant outer membrane proteins (OMPs) such as OmpA, PhoE, and LamB. In this study the substrate profile of Skp was investigated in a proteomics approach. Skp was overexpressed in a deficient E. coli strain as a fusion protein with the Strep-tag and captured, together with any host proteins associated with it, from the periplasmic cell extract under mild conditions via one-step Strep-Tactin affinity chromatography. Copurified substrate proteins were then identified by high resolution 2-DE with immobilized pH-gradients, followed by MALDI-TOF MS. Apart from the known Skp substrates, including OmpA and LamB, more than 30 other interacting proteins were detected, especially from the outer membrane, among these FadL and BtuB, and from the periplasm such as MalE and OppA. Thus, Skp does not only serve as a specialized chaperone for a small set of OMPs, but it seems to exhibit a broader substrate spectrum, including soluble periplasmic proteins. These findings should prompt further investigation into the physiological role of Skp and may promote its use for the bacterial production of biochemically active heterologous proteins whose folding requires secretion into the oxidizing milieu of the periplasm.

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To address succession issues, the owners of family firms increasingly transfer their equity to family and charitable foundations, thereby creating so-called foundation-owned firms. This form of succession has become increasingly common in various European countries. A small yet insightful stream of research has emerged comparing the performance of foundation-owned firms against the performance of nonfoundation-owned firms. Our study goes one step further and accounts for the heterogeneous nature of foundation-owned firms. We investigate the role of foundation purpose (family versus charitable foundation), stock market listing, and family involvement. Our results show that firms owned by a family foundation have better accounting performance than firms owned by a charitable foundation. We further find a performance-enhancing effect of family involvement in the firm's management or supervisory board. Contrary to our expectations, we did not observe significant performance differences between private and stock market-listed foundation-owned firms. Our study advances the emergent stream of the foundation-owned (family) firm literature by integrating research on foundation-owned firms with research on family firms. Furthermore, we contribute to the corporate governance literature on ownership effects and blockholder ownership. 2008). This form of succession is increasingly common in the DACH region 1 and in Scandinavian countries, leading to an increasing number of foundation-owned firms in those countries (Fleisch et al., 2018). As this article was written, several well-known firms, such as Aldi, Bosch, Carlsberg, and Ikea, were partially or fully owned by foundations. Some foundation-owned firms, such as those just listed, can still be classified as family firms as the family continues to influence the company's development. Often, the founding family is the ultimate claimant of the dividends of the foundation. In addition, despite having no direct equity ownership (anymore), the family is sometimes still involved in the management and control of the firm, leaving family members many opportunities to shape the firms' activities. A small but growing body of literature has emerged around the performance of foundation-owned firms, thereby mostly focusing on accounting performance. These studies examine the performance differences between foundation-owned firms and other types of firms

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