All microbial biofilms are initiated through direct physical contact between a bacterium and a solid surface, a step that is controlled by inter- and intramolecular forces. Atomic force microscopy and confocal laser scanning microscopy were used simultaneously to observe the formation of a bond between a fluorescent chimeric protein on the surface of a living Escherichia coli bacterium and a so...

This study was conducted to partially characterize and identify the purity of two major outer membrane proteins (OMPs) (with molecular weights of 32,000 and 35,000 [32K and 35K, respectively]) of Pasteurella haemolytica. The 35K and 32K major OMPs, designated Pasteurella outer membrane proteins A and B (PomA and PomB, respectively), were extracted from P. haemolytica by solubilization in N-octy...

Despite the fundamental function of neutrophils (polymorphonuclear leukocytes (PMNs)) in innate immunity, their role in Escherichia coli K1 (EC-K1) -induced meningitis is unexplored. Here we show that PMN-depleted mice are resistant to EC-K1 (RS218) meningitis. EC-K1 survives and multiplies in PMNs for which outer membrane protein ...

Almost all integral membrane proteins found in the outer membranes of Gram-negative bacteria belong to the transmembrane β-barrel family. These proteins are not only important for nutrient uptake and homeostasis, but are also involved in such processes as adhesion, protein secretion, biofilm formation, and virulence. As surface exposed molecules, outer membrane β-barrel proteins are also potent...

The mechanism of insertion and folding of an integral membrane protein has been investigated with the beta-barrel forming outer membrane protein A (OmpA) of Escherichia coli. This work describes a new approach to this problem by combining structural information obtained from tryptophan fluorescence quenching at different depths in the lipid bilayer with the kinetics of the refolding process. Ex...

Chlamydia (C.) pecorum, an obligate intracellular bacterial species commonly found in ruminants, can also occur pigs. However, its significance as a potential porcine pathogen, or commensal, is still unclear. In previous study (Hoffmann et al. 2015), mixed infections of C. suis and pecorum were detected 14 Swiss fattening pig farms. Using these samples, we aimed to investigate the infection dyn...