Search results for "PRD"

Closely Related Archaeal Haloarcula hispanica Icosahedral Viruses HHIV-2 and SH1 Have Nonhomologous Genes Encoding Host Recognition Functions

2012

Studies on viral capsid architectures and coat protein folds have revealed the evolutionary lineages of viruses branching to all three domains of life. A widespread group of icosahedral tailless viruses, the PRD1-adenovirus lineage, was the first to be established. A double -barrel fold for a single major capsid protein is characteristic of these viruses. Similar viruses carrying genes coding for two major capsid proteins with a more complex structure, such as Thermus phage P23-77 and haloarchaeal virus SH1, have been isolated. Here, we studied the host range, life cycle, biochemical composition, and genomic sequence of a new isolate, Haloarcula hispanica icosahedral virus 2 (HHIV-2), which…

Strain Differences in Open-Field and Elevated Plus-Maze Behavior of Rats Without and With Pretest Handling

1998

Behavior of two rat strains was analyzed with and without 1-week pretest handling. Male rats (150-200 g body weight) of the strains PVG/OlaHsd (PVG) and Hsd:Sprague-DawleySD (SPRD) were tested once in a standard open field and an enriched open field and twice in an elevated plus-maze. Behavioral analysis revealed significant differences between the two strains and differential effects of the pretest handling procedure. SPRD rats displayed higher levels of activity and exploratory behavior than the PVG rats, whereas PVG rats were obviously less anxious. One-week pretest handling had an "anxiolytic" effect and changed activity and exploration-related behavior of the animals in both strains. A…

Combination of open field and elevated plus-maze: a suitable test battery to assess strain as well as treatment differences in rat behavior.

1998

Abstract 1. 1. A test battery consisting of a standard open field, an enriched open field and an elevated plus maze was used to study behavior in rats. 2. 2. Male rats of the strains PVG/OlaHsd (PVG) and Sprague-Dawely-Hsd (SPRD) (150–200g body wt) were used to assess interstrain differences as well as handling effects. In a subsequent experiment an other set of male PVG rats (150–200g body wt) treated either with diazepam or zolpidem was used to evaluate the test battery for pharmacological purposes. 3. 3. SPRD rats displayed higher motor activity levels and also higher levels of exploratory behavior than the PVG rats. In contrast plus-maze activity indicated more anxiety of SPRD than PVG …

2021

Studies on the function of PRDM9 in model systems and its evolution during vertebrate divergence shed light on the basic molecular mechanisms of hybrid sterility and its evolutionary consequences. However, information regarding PRDM9-homolog, PRDM7, whose origin is placed in the primate evolutionary tree, as well as information about the fast-evolving DNA-binding zinc finger array of strepsirrhine PRDM9 are scarce. Thus, we aimed to narrow down the date of the duplication event leading to the emergence of PRDM7 during primate evolution by comparing the phylogenetic tree reconstructions of representative primate samples of PRDM orthologs and paralogs. To confirm our PRDM7 paralogization patt…

Bacteriophage selection against a plasmid-encoded sex apparatus leads to the loss of antibiotic-resistance plasmids.

2011

Antibiotic-resistance genes are often carried by conjugative plasmids, which spread within and between bacterial species. It has long been recognized that some viruses of bacteria (bacteriophage; phage) have evolved to infect and kill plasmid-harbouring cells. This raises a question: can phages cause the loss of plasmid-associated antibiotic resistance by selecting for plasmid-free bacteria, or can bacteria or plasmids evolve resistance to phages in other ways? Here, we show that multiple antibiotic-resistance genes containing plasmids are stably maintained in bothEscherichia coliandSalmonella entericain the absence of phages, while plasmid-dependent phage PRD1 causes a dramatic reduction i…

Efficient DNA Packaging of Bacteriophage PRD1 Requires the Unique Vertex Protein P6

2007

ABSTRACT The assembly of bacteriophage PRD1 proceeds via formation of empty procapsids containing an internal lipid membrane, into which the linear double-stranded DNA genome is subsequently packaged. The packaging ATPase P9 and other putative packaging proteins have been shown to be located at a unique vertex of the PRD1 capsid. Here, we describe the isolation and characterization of a suppressor-sensitive PRD1 mutant deficient in the unique vertex protein P6. Protein P6 was found to be an essential part of the PRD1 packaging machinery; its absence leads to greatly reduced packaging efficiency. Lack of P6 was not found to affect particle assembly, because in the P6-deficient mutant infecti…

Purified Membrane-Containing Procapsids of Bacteriophage PRD1 Package the Viral Genome

2009

Icosahedral-tailed double-stranded DNA (dsDNA) bacteriophages and herpesviruses translocate viral DNA into a preformed procapsid in an ATP-driven reaction by a packaging complex that operates at a portal vertex. A similar packaging system operates in the tailless dsDNA phage PRD1 (Tectiviridae family), except that there is an internal membrane vesicle in the procapsid. The unit-length linear dsDNA genome with covalently linked 5'-terminal proteins enters the procapsid through a unique vertex. Two small integral membrane proteins, P20 and P22, provide a conduit for DNA translocation. The packaging machinery also contains the packaging ATPase P9 and the packaging efficiency factor P6. Here we…

Probing protein interactions in the membrane-containing virus PRD1.

2015

PRD1 is a Gram-negative bacteria infecting complex tailless icosahedral virus with an inner membrane. This type virus of the family Tectiviridae contains at least 18 structural protein species, of which several are membrane associated. Vertices of the PRD1 virion consist of complexes recognizing the host cell, except for one special vertex through which the genome is packaged. Despite extensive knowledge of the overall structure of the PRD1 virion and several individual proteins at the atomic level, the locations and interactions of various integral membrane proteins and membrane-associated proteins still remain a mystery. Here, we demonstrated that blue native PAGE can be used to probe pro…

Konkursa reģistrs

2016

Konkursa reģistrs ir sistēma apdrošināšanas konkursu un cenu aptauju pārvaldīšanai. Sistēma ir paredzēta lietošanai AAS “BALTA” lokālajā tīklā. Ar Konkursa reģistra sistēmas palīdzību var efektīvi organizēt konkursa dokumentu pārvaldīšanas procesus, meklēšanas funkcijas, kā arī atgādinājumu veidošanu un automātisku izsūtīšanu uz lietotāju e-pastiem.

Non-structural proteins P17 and P33 are involved in the assembly of the internal membrane-containing virus PRD1.

2015

AbstractBacteriophage PRD1, which has been studied intensively at the structural and functional levels, still has some gene products with unknown functions and certain aspects of the PRD1 assembly process have remained unsolved. In this study, we demonstrate that the phage-encoded non-structural proteins P17 and P33, either individually or together, complement the defect in a temperature-sensitive GroES mutant of Escherichia coli for host growth and PRD1 propagation. Confocal microscopy of fluorescent fusion proteins revealed co-localisation between P33 and P17 as well as between P33 and the host chaperonin GroEL. A fluorescence recovery after photobleaching assay demonstrated that the diff…