A bacterial predator-prey interaction was studied using Bdellovibrio and bioluminescent prey bacteria. The attacking bdellovibrio causes decay of bioluminescence, which is correlated with bdellovibrio penetration into the prey. The behavior of the prey and predator populations over time was found to be well described by a Lotka-Volterra model. By using this model, the probability of bdellovibri...

Three ovine-derived cathelicidins, SMAP29, OaBac5mini, and OaBac7.5mini, were compared with respect to their antibacterial activities and interactions with membranes. SMAP29 was confirmed to be alpha-helical, broad spectrum, and able to disrupt both the outer and the cytoplasmic membranes at relatively low concentrations. In contrast, the two proline- and arginine-rich OaBac peptides had more-m...

Some Gram-positive bacteria, including probiotic ones, are covered with an external proteinaceous layer called a surface-layer. Described as a paracrystalline layer and formed by the self-assembly of a surface-layer-protein (Slp), this optional structure is peculiar. The surface layer per se is conserved and encountered in many prokaryotes. However, the sequence of the corresponding Slp protein...

Extracellular secretion of products is the major mechanism by which Gram-negative pathogens communicate with and intoxicate host cells. Vesicles released from the envelope of growing bacteria serve as secretory vehicles for proteins and lipids of Gram-negative bacteria. Vesicle production occurs in infected tissues and is influenced by environmental factors. Vesicles play roles in establishing ...

Bacteria adhere to surfaces by virtue of their interaction forces with a substratum surface. A few decades ago, a paper on bacterial adhesion to surfaces typically would either commence with the statement (15) “bacterial adhesion to surfaces is mediated by highly specific, stereo-chemical interactions between complementary components on the interacting surfaces” or (16, 24) “bacterial adhesion ...

Protein-protein interaction (PPI) networks are essential to understand the fundamental processes governing cell biology. Recently, studying PPI networks becomes possible due to advances in experimental high-throughput genomics and proteomics technologies. Many interactions from such high-throughput studies and most interactions from small-scale studies are reported only in the scientific litera...

The interaction of detergents with photosynthetic systems was studied early by Emil Smith (l), who pointed out the utility of anionic detergents for dispersing chloroplast material. Smith obtained what appeared to be subunits of the pigment complex, and characterized these components by ultracentrifugation. Subsequently, a number of investigators have studied the enzymatic capabilities of chlor...

Emiliania huxleyi is a model coccolithophore micro-alga that generates vast blooms in the ocean. Bacteria are not considered among the major factors influencing coccolithophore physiology. Here we show through a laboratory model system that the bacterium Phaeobacter inhibens, a well-studied member of the Roseobacter group, intimately interacts with E. huxleyi. While attached to the algal cell, ...

Chromatophore fractions isolated from photosynthetic bacteria can catalyze light-dependent phosphorylation of adenosine diphosphate to triphosphate (l-3) and also a variety of lightactivated electron transfer reactions, including photoreduction and photo-oxidation of dyes and pyridine nucleotides (4, 5). Whether or not phosphorylation and such electron transport are independent, can occur simul...

BACKGROUND Previously we reported that the variable outer membrane lipoprotein Vsp1 from the relapsing fever spirochete Borrelia turicatae disseminates from blood to brain better than the closely related Vsp2 [1]. Here we studied the interaction between Vsp1 and Vsp2 with brain endothelium in more detail. METHODOLOGY/PRINCIPAL FINDINGS We compared Vsp1 to Vsp2 using human brain microvascular ...