A unified model for BAM function that takes into account type Vc secretion and species differences in BAM composition

Transmembrane proteins in the outer membrane of Gram-negative bacteria are almost exclusively β-barrels. They are inserted into the outer membrane by a conserved and essential protein complex called the BAM (for β-barrel assembly machinery). In this commentary, we summarize current research into the mechanism of this protein complex and how it relates to type V secretion. Type V secretion systems are autotransporters that all contain a β-barrel transmembrane domain inserted by BAM. In type Vc systems, this domain is a homotrimer. We argue that none of the current models are sufficient to explain BAM function particularly regarding type Vc secretion. We also find that current models based on the well-studied model system Escherichia coli mostly ignore the pronounced differences in BAM composition between different bacterial species. We propose a more holistic view on how all OMPs, including autotransporters, are incorporated into the lipid bilayer

New Media, Networking and Phatic Culture

This article will demonstrate how the notion of ‘phatic communion’ has become an increasingly significant part of digital media culture alongside the rise of online networking practices. Through a consideration of the new media objects of blogs, social networking profiles and microblogs, along with their associated practices, I will argue, that the social contexts of ‘individualization’ and ‘network sociality’, alongside the technological developments associated with pervasive communication and ‘connected presence’ has led to an online media culture increasingly dominated by phatic communications. That is, communications which have purely social (networking) and not informational or dialogic intents. I conclude with a discussion of the potential nihilistic consequences of such a culture