Bdellovibrio bacteriovorus

The bacterium Bdellovibrio bacteriovorus is a predator of other Gram-negative bacteria. The predator invades the prey's periplasm and modifies the prey's cell wall, forming a rounded killed prey, or bdelloplast, containing a live B. bacteriovorus. Redundancy in adhesive processes makes invasive mutants rare. Here, we identify a MIDAS adhesin family protein, Bd0875, that is expressed at the predator-prey invasive junction and is important for successful invasion of prey. A mutant strain lacking bd0875 is still able to form round, dead bdelloplasts; however, 10% of the bdelloplasts do not contain B...

In bacteria, cell poles function as subcellular compartments where proteins localize during specific lifecycle stages, orchestrated by polar "hub" proteins. Whereas most described bacteria inherit an "old" pole from the mother cell and a "new" pole from cell division, generating cell asymmetry at birth, non-binary division poses challenges for establishing cell polarity, particularly for daughter cells inheriting only new poles. We investigated polarity dynamics in the obligate predatory bacterium Bdellovibrio bacteriovorus , proliferating through filamentous growth followed by non-binary division within prey bacteria...

Endogenous endophthalmitis caused by Gram-negative bacteria is an intra-ocular infection that can rapidly progress to irreversible loss of vision. While most endophthalmitis isolates are susceptible to antibiotic therapy, the emergence of resistant bacteria necessitates alternative approaches to combat intraocular bacterial proliferation. In this study the ability of predatory bacteria to limit intraocular growth of Pseudomonas aeruginosa , Serratia marcescens , and Staphylococcus aureus was evaluated in a New Zealand white rabbit endophthalmitis prevention model...

Identified as a newly described species from a biocrust in Svalbard, Norway (78° 54' 8.27″ N 12° 01' 20.34″ E), isolate PAP01T has different characteristics from any known predatory bacteria. The isolate was vibrio-shaped strain that employed flagellar motility. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the isolate clustered within the genus Bdellovibrio in the family Bdellovibrionaceae . 16S rRNA gene sequence similarities between strain PAP01T and the type strain ( Bdellovibrio bacteriovorus HD100) was 95...

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Predatory bacteria, like the model endoperiplasmic bacterium Bdellovibrio bacteriovorus, show several adaptations relevant to their requirements for locating, entering and killing other bacteria. The mechanisms underlying prey recognition and handling remain obscure. Here we use complementary genetic, microscopic and structural methods to address this deficit. During invasion, the B. bacteriovorus protein CpoB concentrates into a vesicular compartment that is deposited into the prey periplasm. Proteomic and structural analyses of vesicle contents reveal several fibre-like proteins, which we name the mosaic adhesive trimer (MAT) superfamily, and show localization on the predator surface before prey encounter...

The development of potent bactericidal antibiotic alternatives is important to address the current antibiotic crisis. A representative example is the topical delivery of predatory Bdellovibrio bacteriovorus bacteria to treat ocular bacterial infection. However, the direct topical use of B. bacteriovorus suspensions has the problem of easy loss and inactivation. Here, a B. bacteriovorus in situ forming hydrogel (BIG) was constructed for the ocular delivery of B. bacteriovorus. BIGs, as a fluid in their primitive state, were temperature- and cation- dually sensitive, which was rapidly transformed into immobile gels in the ocular environment...

Histone proteins bind DNA and organize the genomes of eukaryotes and most archaea, whereas bacteria rely on different nucleoid-associated proteins. Homology searches have detected putative histone-fold domains in a few bacteria, but whether these function like archaeal/eukaryotic histones is unknown. Here we report that histones are major chromatin components in the bacteria Bdellovibrio bacteriovorus and Leptospira interrogans. Patterns of sequence evolution suggest important roles for histones in additional bacterial clades...

Bdellovibrio bacteriovorus, an obligate predatory Gram-negative bacterium that proliferates inside and kills other Gram-negative bacteria, was discovered more than 60 years ago. However, we have only recently begun to understand the detailed cell biology of this proficient bacterial killer. B. bacteriovorus exhibits a peculiar life cycle and bimodal proliferation, and thus represents an attractive model for studying novel aspects of bacterial cell biology. The life cycle of B. bacteriovorus consists of two phases: a free-living non-replicative attack phase and an intracellular reproductive phase...

Endogenous endophthalmitis caused by Gram-negative bacteria is an intra-ocular infection that can rapidly progress to irreversible loss of vision. While most endophthalmitis isolates are susceptible to antibiotic therapy, the emergence of resistant bacteria necessitates alternative approaches to combat intraocular bacterial proliferation. In this study the ability of predatory bacteria to limit intraocular growth of Pseudomonas aeruginosa, Serratia marcescens, and Staphylococcus aureus was evaluated in a New Zealand White rabbit endophthalmitis prevention model...

The accurate distribution of genetic material is crucial for all organisms. In most bacteria, chromosome segregation is achieved by the ParABS system, in which the ParB-bound parS sequence is actively partitioned by ParA. While this system is highly conserved, its adaptation in organisms with unique lifestyles and its regulation between developmental stages remain largely unexplored. Bdellovibrio bacteriovorus is a predatory bacterium proliferating through polyploid replication and non-binary division inside other bacteria...

Bdellovibrio bacteriovorus is a bacterial agent that stands out for its ability to act as a predator against gram-negative bacteria and has found application against antibiotic-resistant pathogens. The aim of this study is to determine the efficacy of Bdellovibrio bacteriovorus against antibiotic-resistant pathogens, particularly those causing infections in surgical incision sites. A total of 6 experimental groups were created in mice, and surgical area infections were initiated with Klebsiella pneumoniae in incision sites...

The bacterial predator Bdellovibrio bacteriovorus is a model for the wider phenomenon of bacteria:bacteria predation, and the specialization required to achieve a lifestyle dependent on prey consumption. Bdellovibrio bacteriovorus is able to recognize, enter and ultimately consume fellow Gram-negative bacteria, killing these prey from within their periplasmic space, and lysing the host at the end of the cycle. The classic phenotype-driven characterization (and observation of predation) has benefitted from an increased focus on molecular mechanisms and fluorescence microscopy and tomography, revealing new features of several of the lifecycle stages...

Bdellovibrio bacteriovorus is a microbial predator that offers promise as a living antibiotic for its ability to kill Gram-negative bacteria, including human pathogens. Even after six decades of study, fundamental details of its predation cycle remain mysterious. Here we used cryo-electron tomography to comprehensively image the lifecycle of B. bacteriovorus at nanometre-scale resolution. With high-resolution images of predation in a native (hydrated, unstained) state, we discover several surprising features of the process, including macromolecular complexes involved in prey attachment/invasion and a flexible portal structure lining a hole in the prey peptidoglycan that tightly seals the prey outer membrane around the predator during entry...

Bdellovibrio bacteriovorus is a predatory bacterium preying upon gram-negative bacteria. As such, B. bacteriovorus has the potential to control antibiotic-resistant pathogens and biofilm populations. To survive and reproduce, B. bacteriovorus must locate and infect a host cell. However, in the temporary absence of prey, it is largely unknown how B. bacteriovorus modulate their motility patterns in response to physical or chemical environmental cues in order to optimize their energy expenditure. To investigate B...

Since its discovery six decades ago, the predatory bacterium Bdellovibrio bacteriovorus has sparked recent interest as a potential remedy to the antibiotic resistance crisis. Here we give a comprehensive historical overview from discovery to progressive developments in microscopy and molecular mechanisms. Research on B. bacteriovorus has moved from curiosity to a new model organism, revealing over time more details on its physiology and fascinating predatory life cycle with the help of a variety of methods...

Soft rot pectobacteria (SRP) are phytopathogens of the genera Pectobacterium and Dickeya that cause soft rots on a wide range of crops and ornamental plants. SRP produce plant cell wall degrading enzymes (PCWDEs), including pectinases. Bdellovibrio and like organisms are bacterial predators that can prey on a variety of Gram-negative species, including SRP. In this research, a low methoxyl pectin (LMP)-based immobilization system for B. bacteriovorus is established. It takes advantage that pectin residues induce PCWDE secretion by the pathogens, bringing upon the release of the encapsulated predators...

Despite a remarkable diversity of lifestyles, bacterial replication has only been investigated in a few model species. In bacteria that do not rely on canonical binary division for proliferation, the coordination of major cellular processes is still largely mysterious. Moreover, the dynamics of bacterial growth and division remain unexplored within spatially confined niches where nutrients are limited. This includes the life cycle of the model endobiotic predatory bacterium Bdellovibrio bacteriovorus, which grows by filamentation within its prey and produces a variable number of daughter cells...

UNLABELLED: Antimicrobial resistance has become one of the most important public health problems of our century. In addition to the spread of resistance, biofilm production also makes the treatment of infections increasingly difficult. Therefore, this study, it was aimed to investigate the effect of the predator bacterium Bdellovibrio bacteriovorus HD100 on various clinical pathogens and their biofilms. A large panel of Gram-positive and negative clinical isolates were included in the study...

Most bacteria, including model organisms such as Escherichia coli, Bacillus subtilis, and Caulobacter crescentus, reproduce by binary fission. However, some bacteria belonging to various lineages, including antibiotic-producing Streptomyces and predatory Bdellovibrio, proliferate by nonbinary fission, wherein three or more chromosome copies are synthesized and the resulting multinucleoid filamentous cell subdivides into progeny cells. Here, we demonstrate for the first time that the predatory bacterium Bdellovibrio bacteriovorus reproduces through both binary and nonbinary fission inside different prey bacteria...