We have performed a systematic search for recombination in the region encoding coat protein and 3′ non-translated natural isolates of potyviruses, largest group plant RNA viruses. The presence recombination, localization cross-over points, were confirmed statistically, by three different methods. Recombination was detected or suspected 18 out 109 potyvirus tested, belonging to four eight virus species, most prevalent potato Y, clear bean common mosaic virus, possible yellow zucchini not...

A range of selected PVY isolates that induce superficial necrosis on potato tubers, originating from several countries, were compared with standard strains PVA, PVV and PVY. Biological properties (e.g., host range, aphid transmissibility relationships based cross‐protection between virus isolates) studied. NN differ the normal C , N PV O by their ability to infect Capsicum annuum but not Chenopodium amaranticolor C. quinoa. All are transmissible Myzus persicae without any significant...

We describe the first virus-like particle of a hyperthermophilic euryarchaeote which was discovered in strain "Pyrococcus abyssi" previously characterized our laboratory. This particle, named PAV1, is lemon-shaped (120 nm x 80 nm), with short tail terminated by fibers, and resembles virus SSV1, type member Fuselloviridae, isolated from Sulfolobus shibatae. Sensitivity to organic solvents detergents suggested that envelope PAV1 may contain lipids addition proteins. It contains double-stranded...

The CRISPR genomic structures (Clustered Regularly Interspaced Short Palindromic Repeats) form a family of repeats that is largely present in archaea and frequent bacteria. On the basis formal model using very few parameters, systematic study all their occurrences available genomes Archaea Bacteria has been carried out. This resulted relational database, CRISPI, which also includes complete repertory associated CRISPR-associated genes (CAS). A user-friendly web interface with many graphical...

Hydrothermal activity was common on the early Earth and associated micro-organisms would most likely have included thermophilic to hyperthermophilic species. 3.5-3.3 billion-year-old, hydrothermally influenced rocks contain silicified microbial mats colonies that must been bathed in warm hot hydrothermal emanations. Could they represent or if so, how were preserved? We present results of an experiment silicify anaerobic, from Archaea Domain Pyrococcus abyssi Methanocaldococcus jannaschii,...

Potato virus Y (PVY) the type member of genus Potyvirus, occurs world-wide as isolates which differ in host range and symptoms caused. The sequences a 5′ segment viral RNA overlapping non-translated region (5′NTR) alone (ten isolates) or 5′NTR adjacent P1 coding (eight were established. These data used to quantify polymorphism 5′-terminal part PVY genome. Nucleotide sequence identity between ranged from 66–100% 70–100% region. lowest amino acid similarity was 77%, illustrating high...

Only one virus-like particle (VLP) has been reported from hyperthermophilic Euryarchaeotes. This VLP, named PAV1, is shaped like a lemon and was isolated strain of "Pyrococcus abyssi," deep-sea isolate. Its genome consists double-stranded circular DNA 18 kb which also present at high copy number (60 per chromosome) free within the host cytoplasm but not integrated into chromosome. Here, we report results complete analysis PAV1 genome. All 25 predicted genes, except 3, are located on strand....

Abstract. The role of viruses at different stages the origin life has recently been reconsidered. It appears that may have accompanied earliest forms life, allowing transition from an RNA to a DNA world and possibly being involved in shaping tree three domains we know presently. In addition, large variety identified extreme environments, hosted by extremophilic microorganisms, ecosystems considered as analogues those early Earth. Traces on Earth were preserved precipitation silica organic...

The present study shows that a large range of potato cultivars (29/33 tested), widely grown in the world, are susceptible to tuber necrotic ringspot disease caused by virus Y. three factors studied this work, which proved influence level necrosis reaction, were, first, plant genotype, since varietal behaviour exhibited differences; second, variations virulence occurred between four isolates tested; and third, environmental conditions, as shown different rates obtained under contrasting...

A novel Gram-stain-negative, strictly aerobic, heterotrophic bacterium, designated 306 T , was isolated from near-surface (109 cm below the sea floor) sediments of Gulf Lions, in Mediterranean Sea. Strain grew at temperatures between 4 and 32 °C (optimum 17–22 °C), pH 6.5 to 9.0 8.0–9.0) 0.5 6.0 % (w/v) NaCl 2.0 %). Its DNA G+C content 58.8 mol%. On basis 16S rRNA gene sequence similarity, isolate belongs class Alphaproteobacteria is related genus Phaeobacter . It shares 98.7 identity with...

The Kerguelen Islands, located in the southern part of Indian Ocean, are very isolated geographically. microbial diversity and communities present on island, especially associated to geothermal springs, have never been analyzed with high-throughput sequencing methods. In this article, we performed first metagenomics analysis microorganisms hot springs. From four assembled metagenomes recovered 42 metagenome-assembled genomes, mostly new putative taxa based phylogenomic analyses overall...

A novel thermophilic, anaerobic and organotrophic bacterium, designated strain MC3 T , was isolated from a coastal thermal spring on Île Saint-Paul in the Southern Indian Ocean. Cells of were motile rods, 0.8–1.0 μm wide 1.0–2.4 long during exponential phase up to 7.0 stationary phase. Strain an organotroph able use diverse organic compounds. It also reduce sulfur sulfide. Growth observed at temperatures ranging 45 70 °C (optimum 60 °C), between pH 5.5 7.5 6) 8 46 g NaCl l −1 26 ). The total...

AbstractRecent experiments to fossilize microorganisms using silica have shown that the fossilization process is far more complex than originally thought; not only play an active role in precipitation but may also remain alive while precipitating on their cell wall. To better understand mechanisms lead preservation of fossilized microbes recent and ancient rocks, we experimentally silicified a Gram-positive bacterium, Geobacillus SP7A, over period five years. The microbial response...

Abstract The syenitic rocks of South Rallier du Baty Intrusive Complex (SRBIC) represent intrusions into the oceanic plateau basalts south‐western Kerguelen Islands. SRBIC was previously interpreted as a typical ring complex due to magma emplacement with cauldron subsidence. Our new structural and geochronological data reveal that it is laccolith built between 11.6 7.9 Ma by successive injections sheets around crust–mantle boundary, an average injection rate 0.8 1.4 × 10 −4 km 3 /year. These...