A central goal of HIV-1 vaccine research is the elicitation of antibodies capable of neutralizing diverse primary isolates of HIV-1. Here we show that focusing the immune response to exposed N-terminal residues of the fusion peptide, a critical component of the viral entry machinery and the epitope of antibodies elicited by HIV-1 infection, through immunization with fusion peptide-coupled carriers and prefusion stabilized envelope trimers, induces cross-clade neutralizing responses. In mice, these immunogens elicited monoclonal antibodies capable of neutralizing up to 31% of a cross-clade panel of 208 HIV-1 strains. Crystal and cryoelectron microscopy structures of these antibodies revealed fusion peptide conformational diversity as a molecular explanation for the cross-clade neutralization. Immunization of guinea pigs and rhesus macaques induced similarly broad fusion peptide-directed neutralizing responses, suggesting translatability. The N terminus of the HIV-1 fusion peptide is thus a promising target of vaccine efforts aimed at eliciting broadly neutralizing antibodies.

A novel circovirus called porcine circovirus type 3 (PCV3) was recently reported to exist in the USA. This circovirus is associated with porcine dermatitis, nephropathy syndrome and reproductive failure. This study reports on the first identification, widely epidemic, different phylogenetic clusters, potential role in sow reproductive failure and possible origins of PCV3 in China.

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Aims:  Shanyin County is one of the most severe endemic arsenism affected areas in China but micro‐organisms that potentially release arsenic from sediments to groundwater have not been studied. Our aim was to identify bacteria with the potential to metabolize or transform arsenic in the sediments. Methods and Results:  Culture and nonculture‐based molecular methods were performed to identify arsenite‐oxidizing bacteria, arsenate‐reducing bacteria and arsenite oxidase genes. Arsenite‐oxidizing bacteria were identified only from the land surface to 7 m underground that were affiliated to α‐ and β‐Proteobacteria. Arsenate‐reducing bacteria were found in almost all the sediment samples with different depths (0–41 m) and mainly belong to γ‐Proteobacteria. Several novel arsenite oxidase genes (aoxBs) were identified from the upper layers of the sediments (0–7 m) and were found to be specific for arsenite‐oxidizing bacteria. Conclusions:  The distribution of arsenite‐oxidizing bacteria in upper layers and arsenate‐reducing bacteria in different depths of the sediments may impact the arsenic release into the nearby tubewell groundwater. Significance and Impact of the Study:  This study provides valuable sources of micro‐organisms (and genes) that may contribute to groundwater arsenic abnormality and may be useful to clean arsenic contaminated groundwater.