Physical, Chemical, and Biological Properties of Chitosan-Coated Alginate Microparticles Loaded with Porcine Interleukin-1β: A Potential Protein Adjuvant Delivery System.

We previously developed chicken interleukin-1β (IL-1β) mutants as single-dose adjuvants that induce protective immunity when co-administered with an avian vaccine. However, livestock such as pigs may require a vaccine adjuvant delivery system that provides long-lasting protection to reduce the need for successive booster doses. Therefore, we developed chitosan-coated alginate microparticles as a carrier for bovine serum albumin (BSA) or porcine IL-1β (pIL-1β) and assessed their physical, chemical, and biological properties.

Structural Insight into the Contributions of the N-Terminus and Key Active-Site Residues to the Catalytic Efficiency of Glutamine Synthetase 2.

Glutamine synthetase (GS) catalyzes the condensation of ammonia and glutamate, along with ATP, to form glutamine. Despite extensive studies on GSs from eukaryotes and prokaryotes, the roles of the N-terminus and other structural features in catalysis remain unclear. Here we report the decameric structure of GS 2 (DmGS2).

Chicken interleukin-1β mutants are effective single-dose vaccine adjuvants that enhance mucosal immune response.

The use of cytokines as adjuvants in poultry is promising because they may enhance immune responses to antigens. In this study, we created two mutants, chicken interleukin-1 beta (ChIL-1β) Q19A and R140A, which exhibited significantly increased in vivo biological activity compared with wild-type ChIL-1β. The potential mucosal adjuvant activity of the mutants Q19A and R140A was evaluated in chickens through the intranasal coadministration of a single dose of the Newcastle disease virus (NDV) vaccine with Q19A or R140A.

Functional characterization of Helicobacter pylori 26695 sedoheptulose 7-phosphate isomerase encoded by hp0857 and its association with lipopolysaccharide biosynthesis and adhesion.

Helicobacter pylori is a notorious human pathogen and the appearance of antibiotic resistance of this bacterium has posed a serious threat to human health. Lipopolysaccharide (LPS) is a key virulence factor and plays important roles in pathogenesis of H. pylori infection.

Structure and function of chicken interleukin-1 beta mutants: uncoupling of receptor binding and in vivo biological activity.

Receptor-binding and subsequent signal-activation of interleukin-1 beta (IL-1β) are essential to immune and proinflammatory responses. We mutated 12 residues to identify sites important for biological activity and/or receptor binding. Four of these mutants with mutations in loop 9 (T117A, E118K, E118A, E118R) displayed significantly reduced biological activity.

Case study of hydrogen bonding in a hydrophobic cavity.

Protein internal hydrogen bonds and hydrophobicity determine protein folding and structure stabilization, and the introduction of a hydrogen bond has been believed to represent a better interaction for consolidating protein structure. We observed an alternative example for chicken IL-1β. The native IL-1β contains a hydrogen bond between the Y157 side-chain OηH and I133 backbone CO, whereby the substitution from Tyr to Phe abolishes the connection and the mutant without the hydrogen bond is more stable.

Structural basis for the specific recognition of IL-18 by its alpha receptor.

Interleukin 18 (IL-18), a member of the IL-1 family of cytokines, is an important regulator of innate and acquired immune responses. It signals through its ligand-binding primary receptor IL-18Rα and accessory receptor IL-18Rβ. Here we report the crystal structure of IL-18 with the ectodomain of IL-18Rα, which reveals the structural basis for their specific recognition.

Proteomics analysis of the DF-1 chicken fibroblasts infected with avian reovirus strain S1133.

Background: Avian reovirus (ARV) is a member of the Orthoreovirus genus in the Reoviridae family. It is the etiological agent of several diseases, among which viral arthritis and malabsorption syndrome are the most commercially important, causing considerable economic losses in the poultry industry. Although a small but increasing number of reports have characterized some aspects of ARV infection, global changes in protein expression in ARV-infected host cells have not been examined.

Circular permutation of chicken interleukin-1 beta enhances its thermostability.

Interleukin-1β is a cytokine critically involved in immune and inflammatory responses. To extend its use as a component of avian vaccines, a circularly permuted chicken interleukin-1β was synthesized that maintains its activity after pre-incubation at high temperatures, unlike wild-type chicken interleukin-1β, which is irreversibly inactivated at high temperatures.

Experimentally validated novel inhibitors of Helicobacter pylori phosphopantetheine adenylyltransferase discovered by virtual high-throughput screening.

Helicobacter pylori is a major etiologic agent associated with the development and maintenance of human gastritis. The goal of this study was to develop novel antibiotics against H. pylori, and we thus targeted H.

Substitution of asparagine 76 by a tyrosine residue induces domain swapping in Helicobacter pylori phosphopantetheine adenylyltransferase.

Phosphopantetheine adenylyltransferase (PPAT) catalyses the penultimate step in coenzyme A biosynthesis in bacteria and is therefore a candidate target for antibacterial drug development. We randomly mutated the residues in the Helicobacter pylori PPAT sequence to identify those that govern protein folding and ligand binding, and we describe the crystal structure of one of these mutants (I4V/N76Y) that contains the mutations I4 → V and N76 → Y. Unlike other PPATs, which are homohexamers, I4V/N76Y is a domain-swapped homotetramer.

Crystal structure and biophysical characterisation of Helicobacter pylori phosphopantetheine adenylyltransferase.

Helicobacter pylori is a bacterium that causes chronic active gastritis and peptic ulcers. Drugs targeting H. pylori phosphopantetheine adenylyltransferase (HpPPAT), which is involved in CoA biosynthesis, may be useful.

Potentiation of cell-mediated immune responses against recombinant HN protein of Newcastle disease virus by recombinant chicken IL-18.

In this study, recombinant fowlpox viruses (rFPV/HN) expressing Newcastle disease virus (NDV) HN protein and rFPV/HN/chIL-18 co-expressing chicken IL-18 (chIL-18) and HN protein have been constructed and characterized. The co-expressed rHN/chIL-18 antigen or rchIL-18, expressed by our previous construct rFPV/chIL-18 and co-administered with NDV rHN, was assessed for its immunostimulatory activities and protection against NDV challenge in 2-week-old chickens. Chickens were vaccinated, intramuscularly, with various amounts of rHN or rHN/chIL-18 mixed with mineral oil.

Immunoadjuvant activities of a recombinant chicken IL-12 in chickens vaccinated with Newcastle disease virus recombinant HN protein.

Recombinant fowlpox virus (rFPV/HN) expressing Newcastle disease virus (NDV) HN gene and rFPV/HN/chIL-12 co-expressing chicken IL-12 (chIL-12) and HN (rHN/chIL-12) genes have been characterized. rHN/chIL-12 or rchIL-12, expressed by our previous construct rFPV/chIL-12, co-administered with rHN was assessed for adjuvant activities of chIL-12. Chickens were vaccinated with various amounts of rHN/chIL-12 mixed with mineral oil (MO), intramuscularly.

Structural and functional comparison of cytokine interleukin-1 beta from chicken and human.

Interleukin-1 beta (IL-1β) is an important cytokine in the immune system. The properties of avian IL-1βs are less well understood than the mammalian IL-1βs, and there is no available structure of avian IL-1βs in the Protein Data Bank. Here, we report the crystal structures of wild-type and Y157F mutant IL-1βs from chicken.

Mitochondrial proteomics analysis of tumorigenic and metastatic breast cancer markers.

Mitochondria are key organelles in mammary cells responsible for several cellular functions including growth, division, and energy metabolism. In this study, mitochondrial proteins were enriched for proteomics analysis with the state-of-the-art two-dimensional differential gel electrophoresis and matrix-assistant laser desorption ionization-time-of-flight mass spectrometry strategy to compare and identify the mitochondrial protein profiling changes between three breast cell lines with different tumorigenicity and metastasis. The proteomics results demonstrate more than 1,500 protein features were resolved from the equal amount pooled from three purified mitochondrial proteins, and 125 differentially expressed spots were identified by their peptide finger print, in which, 33 identified proteins belonged to mitochondrial proteins.

Adjuvant activity of chicken interleukin-12 co-administered with infectious bursal disease virus recombinant VP2 antigen in chickens.

A recombinant fowlpox virus (rFPV/VP2) expressing infectious bursal diseases virus (IBDV) VP2 gene has been constructed. After purification and identification of rFPV/VP2, the adjuvant activity of the recombinant chicken IL-12 (rchIL-12), synthesized by our previous construct of rFPV/chIL-12, in rFPV/VP2-expressed rVP2 antigen was assessed in one-week-old specific-pathogen free chickens. The results indicated that rchIL-12 alone or rchIL-12 plus mineral oil (MO) co-administered with rVP2 antigen significantly enhanced the production of serum neutralization (SN) antibody against IBDV, compared to those with MO alone.

Comparative analysis of receptor binding by chicken and human interleukin-1β.

Interleukin-1β (IL-1β) is an important cytokine in the immune system. Mammalian and avian IL-1βs share only 31-35% sequence identity, and the function of avian IL-1βs is less well understood by comparison. Although chicken and mammalian IL-1βs have similar tertiary structures, these ILs differ significantly with respect to receptor activation.

Development of ELISA kits for antibodies against avian reovirus using the sigmaC and sigmaB proteins expressed in the methyltropic yeast Pichia pastoris.

Both the sigmaC and sigmaB proteins of avian reovirus (ARV) can induce type- and group-specific neutralizing antibodies, respectively. In this study, the full-length of S1133 sigmaC, 1071-1 sigmaC, S1133 sigmaB, and S1133 sigmaC-sigmaB fusion genes of ARV were cloned into a secreted vector pPICZalphaA and then integrated into the chromosome of Pichia pastoris for induced expression. Western blot assay showed that ARV sigmaC, sigmaB, and sigmaC-sigmaB fusion proteins were expressed and secreted into the medium.

Avian reovirus core protein muA expressed in Escherichia coli possesses both NTPase and RTPase activities.

Analysis of the amino acid sequence of core protein muA of avian reovirus has indicated that it may share similar functions to protein mu2 of mammalian reovirus. Since mu2 displayed both nucleotide triphosphatase (NTPase) and RNA triphosphatase (RTPase) activities, the purified recombinant muA ( muA) was designed and used to test these activities. muA was thus expressed in bacteria with a 4.

Structure of the parainfluenza virus 5 F protein in its metastable, prefusion conformation.

Enveloped viruses have evolved complex glycoprotein machinery that drives the fusion of viral and cellular membranes, permitting entry of the viral genome into the cell. For the paramyxoviruses, the fusion (F) protein catalyses this membrane merger and entry step, and it has been postulated that the F protein undergoes complex refolding during this process. Here we report the crystal structure of the parainfluenza virus 5 F protein in its prefusion conformation, stabilized by the addition of a carboxy-terminal trimerization domain.

Structure of the uncleaved ectodomain of the paramyxovirus (hPIV3) fusion protein.

Class I viral fusion proteins share common mechanistic and structural features but little sequence similarity. Structural insights into the protein conformational changes associated with membrane fusion are based largely on studies of the influenza virus hemagglutinin in pre- and postfusion conformations. Here, we present the crystal structure of the secreted, uncleaved ectodomain of the paramyxovirus, human parainfluenza virus 3 fusion (F) protein, a member of the class I viral fusion protein group.

Evidence of nucleotidyl phosphatase activity associated with core protein sigma A of avian reovirus S1133.

Both avian reovirus core protein sigma A purified from virus-infected cell extracts and the purified bacterially expressed protein sigma A (e sigma A) were characterized for their nucleoside triphosphate (NTP) hydrolysis activity by thin-layer chromotography. Protein sigma A from both preparations has a nonspecific nucleotidyl phosphatase activity that hydrolyzes four types of NTP to their corresponding nucleoside di- and monophosphates and free phosphate. The divalent cation requirement for this activity of e sigma A was further examined by the addition of Mn(2+), Mg(2+), Ca(2+), and Zn(2+) ions.