Functional Analysis of Genes Involved in the Biosynthesis of Enterocin NKR-5-3B, a Novel Circular Bacteriocin.

Unlabelled: A putative biosynthetic gene cluster of the enterocin NKR-5-3B (Ent53B), a novel circular bacteriocin, was analyzed by sequencing the flanking regions around enkB, the Ent53B structural gene, using a fosmid library. A region approximately 9 kb in length was obtained, and the enkB1, enkB2, enkB3, and enkB4 genes, encoding putative biosynthetic proteins involved in the production, maturation, and secretion of Ent53B, were identified. We also determined the identity of proteins mediating self-immunity against the effects of Ent53B.

Identification, Characterization, and Three-Dimensional Structure of the Novel Circular Bacteriocin, Enterocin NKR-5-3B, from Enterococcus faecium.

Enterocin NKR-5-3B, one of the multiple bacteriocins produced by Enterococcus faecium NKR-5-3, is a 64-amino acid novel circular bacteriocin that displays broad-spectrum antimicrobial activity. Here we report the identification, characterization, and three-dimensional nuclear magnetic resonance solution structure determination of enterocin NKR-5-3B. Enterocin NKR-5-3B is characterized by four helical segments that enclose a compact hydrophobic core, which together with its circular backbone impart high stability and structural integrity.

Gene cluster responsible for secretion of and immunity to multiple bacteriocins, the NKR-5-3 enterocins.

Enterococcus faecium NKR-5-3, isolated from Thai fermented fish, is characterized by the unique ability to produce five bacteriocins, namely, enterocins NKR-5-3A, -B, -C, -D, and -Z (Ent53A, Ent53B, Ent53C, Ent53D, and Ent53Z). Genetic analysis with a genome library revealed that the bacteriocin structural genes (enkA [ent53A], enkC [ent53C], enkD [ent53D], and enkZ [ent53Z]) that encode these peptides (except for Ent53B) are located in close proximity to each other. This NKR-5-3ACDZ (Ent53ACDZ) enterocin gene cluster (approximately 13 kb long) includes certain bacteriocin biosynthetic genes such as an ABC transporter gene (enkT), two immunity genes (enkIaz and enkIc), a response regulator (enkR), and a histidine protein kinase (enkK).

Behçet's disease complicated by multiple aseptic abscesses of the liver and spleen.

Aseptic abscesses are an emergent entity and have been described in inflammatory bowel disease, especially in Crohn's disease, and in other diseases. However, aseptic abscesses associated with Behçet's disease are extremely rare. We report a Japanese male diagnosed with an incomplete type of Behçet's disease who developed multiple aseptic abscesses of the spleen and liver.

Resistance to malaria by enhanced phagocytosis of erythrocytes in LMP7-deficient mice.

General cellular functions of proteasomes occur through protein degradation, whereas the specific function of immunoproteasomes is the optimization of antigen processing associated with MHC class I. We and others previously reported that deficiency in subunits of immunoproteasomes impaired the activation of antigen-specific CD8(+) T cells, resulting in higher susceptibility to tumor and infections. We demonstrated that CD8(+) T cells contributed to protection against malaria parasites.

Antiangiogenic tumor therapy by DNA vaccine inducing aquaporin-1-specific CTL based on ubiquitin-proteasome system in mice.

Aquaporin-1 (AQP-1) is a water channel protein highly expressed in the vascular endothelial cells of proliferating tissues including malignant cancers. Given that in APC ubiquitinated peptides are effectively introduced into proteasomes from which CD8 epitopes are excised, we fused ubiquitin with AQP-1 (pUB-AQP-1) to produce a DNA vaccine. In C57BL/6J mice immunized with pUB-AQP-1, the growth of B16F10 melanoma was profoundly inhibited.

Identification of enterocin NKR-5-3C, a novel class IIa bacteriocin produced by a multiple bacteriocin producer, Enterococcus faecium NKR-5-3.

The structure of enterocin NKR-5-3C, an anti-listerial bacteriocin produced by a multiple bacteriocin producer, Enterococcus faecium NKR-5-3, was determined. Enterocin NKR-5-3C is a novel class IIa bacteriocin that possesses an YGNGL motif sequence and two disulfide bridges in its structure. It is encoded on gene ent53C together with an 18-amino-acid-residue double glycine leader peptide.

Monitoring of the multiple bacteriocin production by Enterococcus faecium NKR-5-3 through a developed liquid chromatography and mass spectrometry-based quantification system.

Enterococcus faecium NKR-5-3 produces four antimicrobial peptides referred here as enterocins NKR-5-3A, B, C and D. A two-step electrospray ionization-liquid chromatography and mass spectrometry (ESI-LC/MS)-based quantification system was developed to monitor its multiple bacteriocin production profiles, which is essential in understanding the complex production regulation mechanism of strain NKR-5-3. The developed ESI-LC/MS-based quantification system can easily monitor the multiple bacteriocin production of this strain.

Purification and characterization of multiple bacteriocins and an inducing peptide produced by Enterococcus faecium NKR-5-3 from Thai fermented fish.

Enterocins NKR-5-3A, B, C, and D were purified from the culture supernatant of Enterococcus faecium NKR-5-3 and characterized. Among the four purified peptides, enterocin NKR-5-3A (5242.3 Da) was identical to brochocin A, produced by Brochothrix campestris ATCC 43754, in mature peptides, and its putative synergistic peptide, enterocin NKR-5-3Z, was found to be encoded in ent53Z downstream of ent53A, encoding enterocin NKR-5-3A.

CD8 T-cell activation in mice injected with a plasmid DNA vaccine encoding AMA-1 of the reemerging Korean Plasmodium vivax.

Relatively little has been studied on the AMA-1 vaccine against Plasmodium vivax and on the plasmid DNA vaccine encoding P. vivax AMA-1 (PvAMA-1). In the present study, a plasmid DNA vaccine encoding AMA-1 of the reemerging Korean P.

Involvement of CD8+ T cells in protective immunity against murine blood-stage infection with Plasmodium yoelii 17XL strain.

When developing malaria vaccines, the most crucial step is to elucidate the mechanisms involved in protective immunity against the parasites. We found that CD8(+) T cells contribute to protective immunity against infection with blood-stage parasites of Plasmodium yoelii. Infection of C57BL/6 mice with P.

Identification and characterization of novel multiple bacteriocins produced by Leuconostoc pseudomesenteroides QU 15.

Aim: To characterize novel multiple bacteriocins produced by Leuconostoc pseudomesenteroides QU 15.

Methods And Results: Leuconostoc pseudomesenteroides QU 15 isolated from Nukadoko (rice bran bed) produced novel bacteriocins. By using three purification steps, four antimicrobial peptides termed leucocin A (ΔC7), leucocin A-QU 15, leucocin Q and leucocin N were purified from the culture supernatant.

Genetic immunization based on the ubiquitin-fusion degradation pathway against Trypanosoma cruzi.

Cytotoxic CD8(+) T cells are particularly important to the development of protective immunity against the intracellular protozoan parasite, Trypanosoma cruzi, the etiological agent of Chagas disease. We have developed a new effective strategy of genetic immunization by activating CD8(+) T cells through the ubiquitin-fusion degradation (UFD) pathway. We constructed expression plasmids encoding the amastigote surface protein-2 (ASP-2) of T.

Critical role for the immunoproteasome subunit LMP7 in the resistance of mice to Toxoplasma gondii infection.

Proteasome-mediated proteolysis is responsible for the generation of immunogenic epitopes presented by MHC class I molecules, which activate antigen-specific CD8+ T cells. Immunoproteasomes, defined by the presence of the three catalytic subunits LMP2, MECL-1, and LMP7, have been hypothesized to optimize MHC class I antigen processing. In this study, we demonstrate that the infection of mice with a protozoan parasite, Toxoplasma gondii, induced the expression of LMP7 mRNA in APC and increased the capacity of APC to induce the production of IFN-gamma by antigen-specific CD8+ T cells.

Psychosedation with dexmedetomidine hydrochloride during minor oral surgery.

We performed intravenous sedation with dexmedetomidine hydrochloride during minor oral surgery and compared this agent with propofol. Patients were randomly divided into 2 groups: dexmedetomidine hydrochloride (D) and propofol (P) groups. In Group D, systolic blood pressure (SBP) increased immediately after the start of initial loading, although no significant differences were noted.

Concurrent infection with Heligmosomoides polygyrus suppresses anti-Plasmodium yoelii protection partially by induction of CD4(+)CD25(+)Foxp3(+) Treg in mice.

Malaria and intestinal nematode infection are widespread and co-infection frequently occurs. We investigated whether co-infected intestinal nematodes modulate immunity against co-existing malaria parasites. Infection of C57BL/6 mice with Plasmodium yoelii 17XNL (Py) was transient and self-limiting, but preceding infection with Heligmosomoides polygyrus (Hp), a mouse intestinal nematode, exacerbated malaria resulting in higher parasite burdens and poor survival of the mice.

Efficient protective immunity against Trypanosoma cruzi infection after nasal vaccination with recombinant Sendai virus vector expressing amastigote surface protein-2.

Chagas' disease, caused by infection with the protozoan parasite Trypanosoma cruzi (T. cruzi), is intractable showing a high mortality rate, and the development of effective vaccines is much desired. To examine the efficacy of a new mode of recombinant viral vaccine, we constructed two non-transmissible Sendai viruses (rSeV/dF) encoding the full-length parasite antigen amastigote surface protein-2 (ASP2) or ASP2 fused with a mono-ubiquitin on its N-terminus (UASP2).

Birefringent all-solid hybrid microstructured fiber.

We report the characterization of a birefringent all-solid hybrid microstructured fiber, in which the core-modes are guided by both the photonic bandgap (PBG) effect and total internal reflection (TIR). Due to the twofold symmetry, modal birefringence of 1.5 x 10(-4) and group birefringence of 2.

Heterozygosity for leptin receptor (fa) accelerates hepatic triglyceride accumulation without hyperphagia in Zucker rats.

Leptin, ob gene product, and its receptors are involved in the regulation of peripheral lipid and glucose metabolism. The present study sought to clarify the functional role of peripheral leptin receptors in hepatic lipid metabolism through analysis of Zucker rats (fa/fa, +/fa), as complete or partial leptin receptor insufficiency models, respectively. In Zucker fa/fa rats, calorie intake, body weight, liver weight, hepatic triglyceride content and serum insulin, triglycerides, FFA, and leptin were elevated compared to lean littermates (+/+ rats).

Identification and characterization of lactocyclicin Q, a novel cyclic bacteriocin produced by Lactococcus sp. strain QU 12.

Lactococcus sp. strain QU 12, which was isolated from cheese, produced a novel cyclic bacteriocin termed lactocyclicin Q. By using cation-exchange chromatography, hydrophobic interaction chromatography, and reverse-phase high-performance liquid chromatography, lactocyclicin Q was purified from culture supernatant, and its molecular mass was determined to be 6,062.

Concurrent infection with Heligmosomoides polygyrus modulates murine host response against Plasmodium berghei ANKA infection.

We investigated whether concurrent infection with Heligmosomoides polygyrus, an intestinal nematode, modulated anti-malaria parasite immunity and development of experimental cerebral malaria (ECM) in mice. The C57BL/6 mice infected with Plasmodium berghei ANKA showed typical symptoms of ECM. Interestingly, preceding H.

Metastasis of hepatocellular carcinoma to spleen and small intestine.

Metastasis of cancer to the spleen or small intestine is rare. We encountered a case of hepatocellular carcinoma (HCC) with splenic and jejunal metastases. A 60-year-old man was referred to us in February 2005 with a diagnosis of splenic tumor.

Critical contribution of immunoproteasomes in the induction of protective immunity against Trypanosoma cruzi in mice vaccinated with a plasmid encoding a CTL epitope fused to green fluorescence protein.

Acquired immunity against infection with Trypanosoma cruzi is dependent on CD8(+)T cells. Here, to develop a vaccine strategy taking advantage of activated CD8(+)T cells, we constructed a DNA vaccine, designated pGFP-TSA1, encoding a fusion protein linking GFP to a single CTL epitope of TSA1, a leading candidate for vaccine against T. cruzi.

Malaria parasites require TLR9 signaling for immune evasion by activating regulatory T cells.

Malaria is still a life-threatening infectious disease that continues to produce 2 million deaths annually. Malaria parasites have acquired immune escape mechanisms and prevent the development of sterile immunity. Regulatory T cells (Tregs) have been reported to contribute to immune evasion during malaria in mice and humans, suggesting that activating Tregs is one of the mechanisms by which malaria parasites subvert host immune systems.

Antigen-specific CD8+ T cells induced by the ubiquitin fusion degradation pathway.

We have developed a DNA vaccine encoding a fusion protein of ubiquitin (Ub) and target proteins at the N-terminus for effective induction of antigen-specific CD8(+) T cells. A series of expression plasmids encoding a model antigen, ovalbumin (OVA), fused with mutated Ub, was constructed. Western blotting analyses using COS7 cells transfected with these plasmids revealed that there were three types of amino acid causing different binding capacities between Ub and OVA.