In this note, we describe the application of isoelectric focusing to the characterization of two cytolytic proteins, the a-toxin or phospholipase C of Clostridium perfringens (clostridial PLC) and cereolysin. We used a 110-ml electrolysis column (LKB Instruments, Rockville, Md.), the design of which was given by 0. Vesterberg et al. (Biochem. Biophys. Acta 133:435, 1967), who also summarized th...

The large phylogenetic distance separating eukaryotic genes and their archaeal orthologs has prevented identification of the position of the eukaryotic root in phylogenomic studies. Recently, an innovative approach has been proposed to circumvent this issue: the use as phylogenetic markers of proteins that have been transferred from bacterial donor sources to eukaryotes, after their emergence f...

Affinity purification is based on the selective and reversible interaction between two binding partners, of which one is bound to a chromatography matrix and the other may be either a native target protein or a recombinant protein fused with an affinity tag (Cuatrecasas et al. 1968). Recombinant DNA-technology allows straightforward construction of gene fusions to provide fusion proteins with t...

Mitochondria evolved from an endosymbiotic proteobacterium in a process that required the transfer of genes from the bacterium to the host cell nucleus, and the translocation of proteins thereby made in the host cell cytosol into the internal compartments of the organelle. According to current models for this evolution, two highly improbable events are required to occur simultaneously: creation...

M any mammalian and plant pathogenic bacteria inject virulence effector proteins into host cells by means of the type III secretion system (TTSS) (1). Effector proteins attack the host innate immune system, modify cytoskeleton and membranes, or alter vesicle trafficking (2, 3). The collective action of these proteins promotes bacterial entry into, growth and movement within, and dissemination f...

The bacterial periplasm is of special interest whenever cell factories are designed and engineered. Recombinantely produced proteins are targeted to the periplasmic space of Gram negative bacteria to take advantage of the authentic N-termini, disulfide bridge formation and easy accessibility for purification with less contaminating cellular proteins. The oxidizing environment of the periplasm p...

Autophagy is one of the main cellular degradation systems in eukaryotes, responsible for the elimination of long-lived proteins and damaged organelles. Besides its well-documented role as a housekeeping mechanism, autophagy has recently caught the attention of groups working in the fields of microbiology and immunology, especially those working in innate immunity. In particular, the highly spec...

Membrane remodeling of targeted host cells is a necessary action for successful bacterial subversion the host. This includes formation membrane ruffles pathogen entry or reprogramming endomembranes during intracellular trafficking. The importance BAR domain-containing proteins in such diverse cellular functions highlights their hijacking by pathogens. Given implication variety functions, as end...

At least nine different bacterial proteins belong to the LysR family. The gene sequence for one of these proteins is presented here. Six others (Escherichia coli LysR, IlvY, CysB; Salmonella typhimurium MetR; Rhizobium NodD; and Enterobacter cloacae AmpR) are known to activate other genes. Based on sequence alignments, each member of this family is predicted to have a helix-turn-helix DNA bindi...