Lethal infections by strains of the highly-pathogenic avian influenza virus (HPAIV) H5N1 pose serious threats to both the poultry industry and public health worldwide. A lack of confirmed HPAIV epitopes recognized by cytotoxic T lymphocytes (CTLs) has hindered the utilization of CD8+ T-cell–mediated immunity and has precluded the development of effectively diversified epitope-based vaccination approaches. In particular, an HPAIV H5N1 CTL-recognized epitope based on the peptide MHC-I–β2m (pMHC-I) complex has not yet been designed. Here, screening a collection of selected peptides of several HPAIV strains against a specific pathogen-free pMHC-I (pBF2*1501), we identified a highly-conserved HPAIV H5N1 CTL epitope, named HPAIV–PA123–130. We determined the structure of the BF2*1501–PA123–130 complex at 2.1 Å resolution to elucidate the molecular mechanisms of a preferential presentation of the highly-conserved PA123–130 epitope in the chicken B15 lineage. Conformational characteristics of the PA123–130 epitope with a protruding Tyr-7 residue indicated that this epitope has great potential to be recognized by specific TCRs. Moreover, significantly increased numbers of CD8+ T cells specific for the HPAIV–PA123–130 epitope in peptide-immunized chickens indicated that a repertoire of CD8+ T cells can specifically respond to this epitope. We anticipate that the identification and structural characterization of the PA123–130 epitope reported here could enable further studies of CTL immunity against HPAIV H5N1. Such studies may aid in the development of vaccine development strategies using well-conserved internal viral antigens in chickens.

Bacterial biofilms are cellular communities that produce an adherent matrix. Exopolysaccharides are key structural components of this matrix and are required for the assembly and architecture of biofilms produced by a wide variety of microorganisms. The human bacterial pathogens Escherichia coli and Salmonella enterica produce a biofilm matrix composed primarily of the exopolysaccharide phosphoethanolamine (pEtN) cellulose. Once thought to be composed of only underivatized cellulose, the pEtN modification present in these matrices has been implicated in the overall architecture and integrity of the biofilm. However, an understanding of the mechanism underlying pEtN derivatization of the cellulose exopolysaccharide remains elusive. The bacterial cellulose synthase subunit G (BcsG) is a predicted inner membrane–localized metalloenzyme that has been proposed to catalyze the transfer of the pEtN group from membrane phospholipids to cellulose. Here we present evidence that the C-terminal domain of BcsG from E. coli (EcBcsGΔN) functions as a phosphoethanolamine transferase in vitro with substrate preference for cellulosic materials. Structural characterization of EcBcsGΔN revealed that it belongs to the alkaline phosphatase superfamily, contains a Zn2+ ion at its active center, and is structurally similar to characterized enzymes that confer colistin resistance in Gram-negative bacteria. Informed by our structural studies, we present a functional complementation experiment in E. coli AR3110, indicating that the activity of the BcsG C-terminal domain is essential for integrity of the pellicular biofilm. Furthermore, our results established a similar but distinct active-site architecture and catalytic mechanism shared between BcsG and the colistin resistance enzymes.

Uber lost US$2.9 billion in the first quarter as its overseas investments were hammered by the coronavirus pandemic, but the company is looking to its growing food delivery business and aggressive cost-cutting to ease the pain. The ride-hailing...

(CMC): Trinidad and Tobago says its borders are to remain closed until June, even as it embarks on softening restrictions to re energise the economy, which had been halted by COVID-19.   Prime Minister Dr Keith Rowley said the...

Mother’s Day is usually a much-anticipated, celebratory day for Trinette Lilly and her siblings. However, this year, they were not looking forward to today because it marks the first anniversary of the brutal slaying of their mother, Antonette...

This book explores how developing-country governments have institutionalized ties with emigrants and their descendents. It offers an unprecedented taxonomy of 45 diaspora-engaging institutions found in 30 developing countries, exploring their activities and objectives. It also provides important practitioner insights from Mali, Mexico, and the Philippines.

Este manual ofrece a los formuladores de políticas y especialistas una guía accesible y práctica sobre las iniciativas gubernamentales referentes a la diáspora. Este manual contiene un menú, seleccionado cuidadosamente, de opciones normativas y programáticas viables basadas en experiencias reales en distintas partes del mundo.

A Calgary coffee shop must close public access to its patio and dine-in services, Alberta Health Services says.

The family owned Army & Navy department store chain is closing after more than a century in business.

Rose (Scotland) as been developing a growing ministry among residents at a local retirement community. What started with a single conversation has grown into a ministry that impacts many lives through friendship and community outreach.

Bloody feet. Blisters. That wasn’t the expectation of eager Transform participants who left the conference in Rome to join OM Spain on a unique journey.

By visiting a local park in Catalonia regularly, to get to know the youth, and handing out little bags of toasted corn, the OM team are able to make friendships and share seeds of faith

A new partner ministry broadcasting Urdu-speaking programmes to 360+ million who speak it, is giving them hope for eternity.

MSPS were really quite excited last week to be taking part in a largely symbolic vote with an entirely predictable outcome.

The leader said: "This is a secret; if we started to teach about Jesus in our mosques then we might as well open churches."

THERE was a popular fad in the 1990s for presenting music in its rawest form. Rather than the traditional bombast of turning everything up to 11, MTV Unplugged stripped it back to the basics. Often it was simply one singer, one guitar and a stool. And it was hugely popular.

The leader said: "This is a secret; if we started to teach about Jesus in our mosques then we might as well open churches."

The leader said: "This is a secret; if we started to teach about Jesus in our mosques then we might as well open churches."

Barranquilla, Colombia :: Logos Hope's focus for her time in Latin America is to encourage Latinos to serve God around the world.

The leader said: "This is a secret; if we started to teach about Jesus in our mosques then we might as well open churches."

The leader said: "This is a secret; if we started to teach about Jesus in our mosques then we might as well open churches."

Bernard Guidicelli said that the French federation (FFT) had "no regrets" over its decision to move Roland Garros from May 24-June 7 to September 20-October 4.

India reported 3,277 new coronavirus patients in the last 24 hours and 128 deaths linked to the illness that brings the total number of cases in the country to 62,939, including 2,109 deaths, the...