Zirconolite and xenotime U-Pb age constraints on the emplacement of the Golden Mile Dolerite silland gold mineralization at the Mt Charlotte mine, Eastern Goldfields Province, Yilgarn Craton, Western Australia.

In situ SHRIMP U-Pb dating of magmatic zirconolite (CaZrTi2O7) in the Golden Mile Dolerite from the Mt Charlotte gold deposit (Yilgarn Craton, Australia) has yielded the first robust emplacement age (2,680 9 Ma) for the principle host-rock of gold mineralization in the Kalgoorlie district. In contrast, comagmatic zircon gave ages from approx 2.68 Ga to approx 2.17 Ga, reflecting isotopic resetting of high-U and -Th crystals. In situ SHRIMP analysis of hydrothermal xenotime (YPO4), which co-exists with gold in alteration pyrite, provided a Pb/Pb isochron age of 2,655 13 Ma. This date indicates that the youngest deposit in the Kalgoorlie district (Mt Charlotte) formed at approx 2.65 Ga, and provides a new minimum age for the structurally older Golden Mile deposit. Our results indicate that gold mineralization at Mt Charlotte is approx 50 million years older than indicated by recent 40Ar/39Ar dating and places new constraints on the timing of late-stage regional faulting (D4) in the province

Bioinformatics and evolutionary insight on the spike glycoprotein gene of QX-like and Massachusetts strains of infectious bronchitis virus

<p>Abstract</p> <p>Background</p> <p>Infectious bronchitis virus (IBV) is a Gammacoronavirus of the family C<it>oronaviridae</it> and is a causative agent of an economically important disease in poultry. The spike glycoprotein of IBV is essential for host cell attachment, neutralization, and is involved in the induction of protective immunity. Previously obtained sequence data of the spike gene of IBV QX-like and Massachusetts strains were subjected to bioinformatics analysis.</p> <p>Findings</p> <p>On analysis of potential phosphorylation sites, the Ser542 and Ser563 sites were not present in Massachusetts strains, while QX-like isolates did not have the Ser534 site. Massachusetts and QX-like strains showed different cleavage site motifs. The N-glycosylation sites ASN-XAA-SER/THR-55, 147, 200 and 545 were additionally present in QX-like strains. The leucine-rich repeat regions in Massachusetts strains consisted of stretches of 63 to 69 amino acids, while in the QX-like strains they contained 59 amino acids in length. An additional palmitoylation site was observed in CK/SWE/082066/2010 a QX-like strain. Primary structure data showed difference in the physical properties and hydrophobic nature of both genotypes. The comparison of secondary structures revealed no new structural domains in the genotypic variants. The phylogenetic analyses based on avian and mammalian coronaviruses showed the analysed IBV as closely related to turkey coronaviruses and distantly related to thrush and munia coronaviruses.</p> <p>Conclusion</p> <p>The study demonstrated that spike glycoprotein of the Massachusetts and the QX-like variants of IBV are molecularly distinct and that this may reflect in differences in the behavior of these viruses in vivo.</p

The Viruses of Wild Pigeon Droppings

<div><p>Birds are frequent sources of emerging human infectious diseases. Viral particles were enriched from the feces of 51 wild urban pigeons (<i>Columba livia</i>) from Hong Kong and Hungary, their nucleic acids randomly amplified and then sequenced. We identified sequences from known and novel species from the viral families <i>Circoviridae, Parvoviridae, Picornaviridae, Reoviridae, Adenovirus, Astroviridae,</i> and <i>Caliciviridae (listed in decreasing number of reads)</i>, as well as plant and insect viruses likely originating from consumed food. The near full genome of a new species of a proposed parvovirus genus provisionally called <i>Aviparvovirus</i> contained an unusually long middle ORF showing weak similarity to an ORF of unknown function from a fowl adenovirus. Picornaviruses found in both Asia and Europe that are distantly related to the turkey megrivirus and contained a highly divergent 2A1 region were named mesiviruses. All eleven segments of a novel rotavirus subgroup related to a chicken rotavirus in group G were sequenced and phylogenetically analyzed. This study provides an initial assessment of the enteric virome in the droppings of pigeons, a feral urban species with frequent human contact.</p></div