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1.
Science ; 384(6694): 458-465, 2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38662818

ABSTRACT

Based on an extensive model intercomparison, we assessed trends in biodiversity and ecosystem services from historical reconstructions and future scenarios of land-use and climate change. During the 20th century, biodiversity declined globally by 2 to 11%, as estimated by a range of indicators. Provisioning ecosystem services increased several fold, and regulating services decreased moderately. Going forward, policies toward sustainability have the potential to slow biodiversity loss resulting from land-use change and the demand for provisioning services while reducing or reversing declines in regulating services. However, negative impacts on biodiversity due to climate change appear poised to increase, particularly in the higher-emissions scenarios. Our assessment identifies remaining modeling uncertainties but also robustly shows that renewed policy efforts are needed to meet the goals of the Convention on Biological Diversity.


Subject(s)
Biodiversity , Climate Change , Extinction, Biological
2.
Plast Reconstr Surg Glob Open ; 12(2): e5618, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38375370

ABSTRACT

Hereditary skin laxity is a rare condition, some cases of which are also referred to as cutis laxa, and those involving facial skin are considered a target for treatment by plastic surgery as patients present with an aged face, which can reduce their quality of life. In some of these patients, the facial nerve and muscles may be affected, and cause weakness of mimetic muscles. We performed one-stage bilateral lengthening temporalis myoplasty reanimation, followed by lower facial contouring with partial lower lip excision and hammock-shaped fascia grafting in two patients with hereditary facial skin laxity coexisting with facial palsy. The patient was a 63-year-old woman with hereditary gelsolin amyloidosis and a 64-year-old man who was diagnosed with oculopharyngeal muscular dystrophy. Postoperatively, a symmetrical facial contour was achieved in repose, and smiling with and without biting was possible. To our knowledge, there are no reports of dynamic smile reconstruction for facial weakness in patients with hereditary facial skin laxity. Although these patients may experience progressive loss of function of the trigeminal nerve and its innervating muscles, the static suspension effect of lengthening temporalis myoplasty can be expected to continue even if the temporal muscles lose their function in the future. We believe that, with careful patient selection, dynamic reconstruction is an option for progressive facial paralysis. In this article, we present the chronological history of two patients who underwent multiple plastic surgery procedures and discuss the importance of the role of plastic surgery in improving the quality of life under these conditions.

4.
Clin Case Rep ; 11(5): e7356, 2023 May.
Article in English | MEDLINE | ID: mdl-37215962

ABSTRACT

Key Clinical Message: Epidural pneumatosis and pneumomediastinum are rare, benign complications of diabetic ketoacidosis. As they can mimic serious conditions including esophageal rupture, diagnostic evaluation, and attentive monitoring are crucial. Abstract: Diabetic ketoacidosis can rarely present with epidural pneumatosis and pneumomediastinum, possibly due to forceful vomiting and Kussmaul breathing. Recognizing these pneumocomplications is crucial, as they can mimic severe conditions, including esophageal rupture. Consequently, diagnostic workup and vigilant monitoring are critical, even though these pneumocomplications are typically benign and self-resolving.

5.
Sci Total Environ ; 824: 153697, 2022 Jun 10.
Article in English | MEDLINE | ID: mdl-35143798

ABSTRACT

Climate change has the potential to cause forest range shifts at a broad scale and consequently can alter crucial forest functions, including carbon sequestration. However, global-scale projections of future forest range shifts remain challenging because our knowledge of the physiological responses of plants to climatic stress is limited to particular species and is insufficient for wide-range projections, in addition to the uncertainties in the impacts of non-climatic factors, such as wildfire, wind, and insect outbreaks. To evaluate the vulnerability and resilience of forests to climate change, we developed a new empirical approach using climatic indices reflecting physiological stressors on plants. We calculated the global distributions of seven indices based on primary climatic stressors (drought, solar radiation, and temperature) at high resolution. We then modeled the relationship between the seven indices and global forest extent. We found two key stressors driving climate-induced forest range shifts on a global scale: low temperature under high radiation and drought. At high latitudes of the Northern Hemisphere, forest establishment became difficult when the mean temperature was less than approximately 7.2 °C in the highest radiation quarter. Forest sensitivity to drought was more pronounced at mid-latitudes. In areas where the humidity index (ratio of precipitation to potential evapotranspiration) was below 0.45, shrubland and grassland became more dominant than forests. Our results also suggested that the impacts of climate change on global forest range shifts will be geographically biased depending on the areas affected by the key climatic stressors. Potential forest gain was remarkable in boreal regions due to increasing temperature. Potential forest loss was remarkable in current tropical grassland and temperate forest/grassland ecoregions due to increasing drought. Our approach using stress-reflecting indices could improve our ability to detect the roles of climatic stressors on climate-induced forest range shifts.


Subject(s)
Forests , Trees , Climate Change , Droughts , Temperature , Trees/physiology
6.
PLoS One ; 15(8): e0230224, 2020.
Article in English | MEDLINE | ID: mdl-32764766

ABSTRACT

The term "oral frailty" reflects the fact that oral health is associated with physical frailty and mortality. The gold standard methods for evaluating the swallowing function have several problems, including the need for specialized equipment, the risk of radiation exposure and aspiration, and general physicians not possessing the requisite training to perform the examination. Hence, several simple and non-invasive techniques have been developed for evaluating swallowing function, such as those for measuring tongue pressure and tongue thickness. The aim of this study was to investigate the relationship between tongue thickness ultrasonography and tongue pressure in the Japanese elderly. We evaluated 254 elderly patients, who underwent tongue ultrasonography and tongue pressure measurement. To determine tongue thickness, we measured the vertical distance from the surface of the mylohyoid muscle to the tongue dorsum using ultrasonography. The results of the analyses revealed that tongue thickness was linearly associated with tongue pressure in both sexes. In male participants, dyslipidemia, lower leg circumference, and tongue pressure were independently and significantly associated with tongue thickness. In female participants, body mass index and tongue pressure were independently and significantly associated with tongue thickness. The optimal cutoff for tongue thickness to predict the tongue pressure of < 20 kPa was 41.3 mm in males, and 39.3 mm in females. In the Japanese elderly, tongue thickness using ultrasonography is associated with tongue pressure. Tongue thickness and tongue pressure, which are sensitive markers for oral frailty, decrease with age. We conclude that tongue ultrasonography provides a less invasive technique for determining tongue thickness and predicts oral frailty for elderly patients.


Subject(s)
Deglutition/physiology , Tongue/physiology , Aged , Aged, 80 and over , Body Mass Index , Female , Frailty , Humans , Japan , Male , Muscle Strength/physiology , Oral Health , Pressure , Ultrasonography/methods
7.
Nat Commun ; 10(1): 5240, 2019 11 20.
Article in English | MEDLINE | ID: mdl-31748549

ABSTRACT

Limiting the magnitude of climate change via stringent greenhouse gas (GHG) mitigation is necessary to prevent further biodiversity loss. However, some strategies to mitigate GHG emission involve greater land-based mitigation efforts, which may cause biodiversity loss from land-use changes. Here we estimate how climate and land-based mitigation efforts interact with global biodiversity by using an integrated assessment model framework to project potential habitat for five major taxonomic groups. We find that stringent GHG mitigation can generally bring a net benefit to global biodiversity even if land-based mitigation is adopted. This trend is strengthened in the latter half of this century. In contrast, some regions projected to experience much growth in land-based mitigation efforts (i.e., Europe and Oceania) are expected to suffer biodiversity loss. Our results support the enactment of stringent GHG mitigation policies in terms of biodiversity. To conserve local biodiversity, however, these policies must be carefully designed in conjunction with land-use regulations and societal transformation in order to minimize the conversion of natural habitats.


Subject(s)
Biodiversity , Climate Change , Ecosystem , Environmental Restoration and Remediation/methods , Greenhouse Gases , Amphibians , Animals , Birds , Climatic Processes , Mammals , Reptiles , Tracheophyta
9.
PLoS One ; 12(8): e0182837, 2017.
Article in English | MEDLINE | ID: mdl-28797067

ABSTRACT

Pine wilt disease (PWD) constitutes a serious threat to pine forests. Since development depends on temperature and drought, there is a concern that future climate change could lead to the spread of PWD infections. We evaluated the risk of PWD in 21 susceptible Pinus species on a global scale. The MB index, which represents the sum of the difference between the mean monthly temperature and 15 when the mean monthly temperatures exceeds 15°C, was used to determine current and future regions vulnerable to PWD (MB ≥ 22). For future climate conditions, we compared the difference in PWD risks among four different representative concentration pathways (RCPs 2.6, 4.5, 6.0, and 8.5) and two time periods (2050s and 2070s). We also evaluated the impact of climate change on habitat suitability for each Pinus species using species distribution models. The findings were then integrated and the potential risk of PWD spread under climate change was discussed. Within the natural Pinus distribution area, southern parts of North America, Europe, and Asia were categorized as vulnerable regions (MB ≥ 22; 16% of the total Pinus distribution area). Representative provinces in which PWD has been reported at least once overlapped with the vulnerable regions. All RCP scenarios showed expansion of vulnerable regions in northern parts of Europe, Asia, and North America under future climate conditions. By the 2070s, under RCP 8.5, an estimated increase in the area of vulnerable regions to approximately 50% of the total Pinus distribution area was revealed. In addition, the habitat conditions of a large portion of the Pinus distribution areas in Europe and Asia were deemed unsuitable by the 2070s under RCP 8.5. Approximately 40% of these regions overlapped with regions deemed vulnerable to PWD, suggesting that Pinus forests in these areas are at risk of serious damage due to habitat shifts and spread of PWD.


Subject(s)
Climate Change , Models, Theoretical , Pinus/growth & development , Plant Diseases , Climate , Ecosystem , Forests , Temperature
10.
Lipids ; 50(11): 1093-102, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26399511

ABSTRACT

Hydroxy and oxo fatty acids were recently found to be produced as intermediates during gut microbial fatty acid metabolism. Lactobacillus plantarum produces these fatty acids from unsaturated fatty acids such as linoleic acid. In this study, we investigated the effects of these gut microbial fatty acid metabolites on the lipogenesis in liver cells. We screened their effect on sterol regulatory element binding protein-1c (SREBP-1c) expression in HepG2 cells treated with a synthetic liver X receptor α (LXRα) agonist (T0901317). The results showed that 10-hydroxy-12(Z)-octadecenoic acid (18:1) (HYA), 10-hydroxy-6(Z),12(Z)-octadecadienoic acid (18:2) (γHYA), 10-oxo-12(Z)-18:1 (KetoA), and 10-oxo-6(Z),12(Z)-18:2 (γKetoA) significantly decreased SREBP-1c mRNA expression induced by T0901317. These fatty acids also downregulated the mRNA expression of lipogenic genes by suppressing LXRα activity and inhibiting SREBP-1 maturation. Oral administration of KetoA, which effectively reduced triacylglycerol accumulation and acetyl-CoA carboxylase 2 (ACC2) expression in HepG2 cells, for 2 weeks significantly decreased Srebp-1c, Scd-1, and Acc2 expression in the liver of mice fed a high-sucrose diet. Our findings suggest that the hypolipidemic effect of the fatty acid metabolites produced by L. plantarum can be exploited in the treatment of cardiovascular diseases or dyslipidemia.


Subject(s)
Fatty Acids/administration & dosage , Hepatocytes/metabolism , Lipid Metabolism/drug effects , Triglycerides/metabolism , Animals , Diet , Fatty Acids/metabolism , Gastrointestinal Microbiome , Gene Expression Regulation/drug effects , Hep G2 Cells , Hepatocytes/microbiology , Humans , Hydrocarbons, Fluorinated , Lactobacillus plantarum/metabolism , Liver/drug effects , Liver/metabolism , Mice , RNA, Messenger/biosynthesis , Sterol Regulatory Element Binding Protein 1/biosynthesis , Sterol Regulatory Element Binding Protein 1/genetics , Sulfonamides , Triglycerides/genetics
11.
J Lipid Res ; 56(7): 1340-50, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25966711

ABSTRACT

Hydroxy FAs, one of the gut microbial metabolites of PUFAs, have attracted much attention because of their various bioactivities. The purpose of this study was to identify lactic acid bacteria with the ability to convert linoleic acid (LA) to hydroxy FAs. A screening process revealed that a gut bacterium, Lactobacillus acidophilus NTV001, converts LA mainly into 13-hydroxy-cis-9-octadecenoic acid and resulted in the identification of the hydratase responsible, fatty acid hydratase 1 (FA-HY1). Recombinant FA-HY1 was purified, and its enzymatic characteristics were investigated. FA-HY1 could convert not only C18 PUFAs but also C20 and C22 PUFAs. C18 PUFAs with a cis carbon-carbon double bond at the Δ12 position were converted into the corresponding 13-hydroxy FAs. Arachidonic acid and DHA were converted into the corresponding 15-hydroxy FA and 14-hydroxy FA, respectively. To the best of our knowledge, this is the first report of a bacterial FA hydratase that can convert C20 and C22 PUFAs into the corresponding hydroxy FAs. These novel hydroxy FAs produced by using FA-HY1 should contribute to elucidating the bioactivities of hydroxy FAs.


Subject(s)
Hydrolases/metabolism , Lactobacillus acidophilus/enzymology , Linoleic Acid/chemistry , Linoleic Acid/metabolism , Biocatalysis , Coenzymes/metabolism , Hydrolases/isolation & purification , Kinetics , Lactobacillus acidophilus/metabolism , Stereoisomerism , Substrate Specificity , Water/metabolism
12.
J Biosci Bioeng ; 119(6): 636-41, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25476761

ABSTRACT

Linoleic acid Δ9 hydratase, which is involved in linoleic acid saturation metabolism of Lactobacillus plantarum AKU 1009a, was cloned, expressed as a his-tagged recombinant enzyme, purified with an affinity column, and characterized. The enzyme required FAD as a cofactor and its activity was enhanced by NADH. The maximal activities for the hydration of linoleic acid and for the dehydration of 10-hydroxy-cis-12-octadecenoic acid (HYA) were observed at 37 °C in buffer at pH 5.5 containing 0.5 M NaCl. Free C16 and C18 fatty acids with cis-9 double bonds and 10-hydroxy fatty acids served as substrates for the hydration and dehydration reactions, respectively. The apparent Km value for linoleic acid was estimated to be 92 µM, with a kcat of 2.6∙10(-2) s(-1) and a Hill factor of 3.3. The apparent Km value for HYA was estimated to be 98 µM, with a kcat of 1.2∙10(-3) s(-1).


Subject(s)
Biocatalysis , Lactobacillus plantarum/enzymology , Lactobacillus plantarum/metabolism , Linoleic Acid/metabolism , Flavin-Adenine Dinucleotide/metabolism , Hydrogen-Ion Concentration , Hydrolases/metabolism , Kinetics , Lipid Metabolism , NAD/metabolism , Oleic Acids/chemistry , Oleic Acids/metabolism , Substrate Specificity , Temperature
13.
J Physiol Anthropol ; 33: 29, 2014 Sep 10.
Article in English | MEDLINE | ID: mdl-25208693

ABSTRACT

BACKGROUND: Obesity and overweight are increasing in prevalence in developed countries as a result of changing dietary habits and a lack of physical activity. The purpose of the present study was to evaluate the changes in body composition during short-term overfeeding using the three-component model, which is composed of fat mass (FM), total body water (TBW), and fat-free dry solids (FFDS). METHODS: Ten healthy men completed 3 days of overfeeding during which they consumed 1,500 kcal/day more energy than consumed in their normal diets. Body composition was evaluated at three time points: the day before and after their normal diets and the day after the 3-day overfeeding diet. RESULTS: Before and after their normal diets, there were no significant differences in body weight and composition, but after 3 days of overfeeding, body weight, TBW, and FFDS increased 0.7, 0.7, and 0.2 kg, respectively (P <0.0001). There was no significant difference in FM between the normal and overfeeding diets. CONCLUSION: This study suggests that TBW gain contributes to weight gain following a short-term overfeeding.


Subject(s)
Body Composition/physiology , Diet , Energy Intake/physiology , Hyperphagia , Adult , Body Water/physiology , Humans , Male , Motor Activity/physiology , Young Adult
14.
Photochem Photobiol ; 90(6): 1397-403, 2014.
Article in English | MEDLINE | ID: mdl-25041035

ABSTRACT

Ultraviolet (UV) irradiation is an increasingly used method of water disinfection. UV rays can be classified by wavelength into UVA (320-400 nm), UVB (280-320 nm), and UVC (<280 nm). We previously developed UVA sterilization equipment with a UVA light-emitting diode (LED). The aim of this study was to establish a new water disinfection procedure using the combined irradiation of the UVA-LED and another UV wavelength. An oxidative DNA product, 8-hydroxy-2'-deoxyguanosine (8-OHdG), increased after irradiation by UVA-LED alone, and the level of cyclobutane pyrimidine dimers (CPDs) was increased by UVC alone in Vibrio parahaemolyticus. Although sequential irradiation of UVA-LED and UVC-induced additional bactericidal effects, simultaneous irradiation with UVA-LED and UVC-induced bactericidal synergistic effects. The 8-OHdG and CPDs production showed no differences between sequential and simultaneous irradiation. Interestingly, the recovery of CPDs was delayed by simultaneous irradiation. The synergistic effect was absent in SOS response-deficient mutants, such as the recA and lexA strains. Because recA- and lexA-mediated SOS responses have crucial roles in a DNA repair pathway, the synergistic bactericidal effect produced by the simultaneous irradiation could depend on the suppression of the CPDs repair. The simultaneous irradiation of UVA-LED and UVC is a candidate new procedure for effective water disinfection.


Subject(s)
Ultraviolet Rays , Vibrio parahaemolyticus/radiation effects , 8-Hydroxy-2'-Deoxyguanosine , Deoxyguanosine/analogs & derivatives , Deoxyguanosine/metabolism , Genes, Bacterial , Pyrimidine Dimers/metabolism , SOS Response, Genetics , Vibrio parahaemolyticus/genetics
15.
Am J Otolaryngol ; 35(5): 577-81, 2014.
Article in English | MEDLINE | ID: mdl-25053186

ABSTRACT

INTRODUCTION: For the nasal reconstruction, local flap using the adjacent tissue is selected from an esthetic viewpoint. The Rintala flap is a useful option, and reconstruction of the glabellar over the nasal tip with this flap is ideal, for which the procedure was modified to increase the blood flow to the Rintala flap to extend its clinical applications. METHODS: For defects of the glabellar over the middle one third of nasal dorsum, the Rintala flap is transferred employing the original design and technique dissected on supraperiosteal plane. For defects of the lower one third of nasal dorsum over the nasal tip, blood supply through the lateral nasal artery is added to the distal end of the flap, preparing a long flap with stable blood supply like Maruyama described in 1997. RESULTS: This procedure was applied for nasal reconstruction in 15 patients. The Rintala flap was applied in 12 and the modified Rintala flap with adding blood flow from the lateral nasal artery was applied in 3. Blood supply to the flap was very stable in all patients, and favorable outcomes were achieved. CONCLUSIONS: Using this procedure, the natural contour and morphology of the glabellar over the nasal tip may be reconstructed. The technique is simple and easy. Using this procedure, clinical applications of the Rintala flap can be extended, showing that it is a useful nasal reconstructive procedure.


Subject(s)
Carcinoma, Basal Cell/surgery , Nose Neoplasms/surgery , Rhinoplasty/methods , Surgical Flaps , Aged , Esthetics , Female , Humans , Middle Aged , Treatment Outcome
16.
Proc Natl Acad Sci U S A ; 110(44): 17808-13, 2013 Oct 29.
Article in English | MEDLINE | ID: mdl-24127592

ABSTRACT

In the representative gut bacterium Lactobacillus plantarum, we identified genes encoding the enzymes involved in a saturation metabolism of polyunsaturated fatty acids and revealed in detail the metabolic pathway that generates hydroxy fatty acids, oxo fatty acids, conjugated fatty acids, and partially saturated trans-fatty acids as intermediates. Furthermore, we observed these intermediates, especially hydroxy fatty acids, in host organs. Levels of hydroxy fatty acids were much higher in specific pathogen-free mice than in germ-free mice, indicating that these fatty acids are generated through polyunsaturated fatty acids metabolism of gastrointestinal microorganisms. These findings suggested that lipid metabolism by gastrointestinal microbes affects the health of the host by modifying fatty acid composition.


Subject(s)
Fatty Acids, Unsaturated/metabolism , Gastrointestinal Tract/microbiology , Lactobacillus plantarum/enzymology , Lipid Metabolism/physiology , Metabolic Networks and Pathways/physiology , Amino Acid Sequence , Animals , Base Sequence , Chromatography, Liquid , Cloning, Molecular , DNA Primers/genetics , Gastrointestinal Tract/metabolism , Lactobacillus plantarum/metabolism , Metabolic Networks and Pathways/genetics , Mice , Molecular Sequence Data , Multigene Family/genetics , Oxidation-Reduction , Oxidoreductases/genetics , Oxidoreductases/metabolism , Sequence Analysis, DNA , Sequence Homology , Specific Pathogen-Free Organisms , Tandem Mass Spectrometry
17.
Org Biomol Chem ; 11(45): 7843-51, 2013 Dec 07.
Article in English | MEDLINE | ID: mdl-24061283

ABSTRACT

We have demonstrated that C60 derivatives bearing a pyrrolidine moiety as well as a variety of other substituents can form 1 : 2 complexes with γ-cyclodextrin (γ-CDx) using a mechanochemical high-speed vibration milling apparatus. When the influence of the steric hindrance of the substituents on the formation of the complexes was negligible, the water-solubilities of the complexes were shown experimentally to be completely dependent on the hydrophobic properties of the substituent. Furthermore, the stabilities of the γ-CDx-complexes of several different C60 derivatives were found to be similar to or slightly higher than that of the C60·Î³-CDx complex, with the solubilities of the complexes showing no correlation to the stabilities. Based on the results of a series of theoretical investigations, we have shown that the stabilities of the γ-CDx-complexes can be affected not only by steric effects but also by the polarities of the substituent groups, which exist in the vicinity of the upper rim of γ-CDx, because the water bound to the polar group can assist in the stabilisation of the complexes.


Subject(s)
Fullerenes/chemistry , gamma-Cyclodextrins/chemistry , Models, Molecular , Molecular Structure , Solubility , Water/chemistry
18.
Glycobiology ; 23(2): 232-40, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23089618

ABSTRACT

Bifidobacterium bifidum is one of the most frequently found bifidobacteria in the intestines of newborn infants. We previously reported that B. bifidum possesses unique metabolic pathways for O-linked glycans on gastrointestinal mucin (Yoshida E, Sakurama H, Kiyohara M, Nakajima M, Kitaoka M, Ashida H, Hirose J, Katayama T, Yamamoto K, Kumagai H. 2012. Bifidobacterium longum subsp. infantis uses two different ß-galactosidases for selectively degrading type-1 and type-2 human milk oligosaccharides. Glycobiology. 22:361-368). The nonreducing termini of O-linked glycans on mucin are frequently covered with histo-blood group antigens. Here, we identified a gene agabb from B. bifidum JCM 1254, which encodes glycoside hydrolase (GH) family 110 α-galactosidase. AgaBb is a 1289-amino acid polypeptide containing an N-terminal signal sequence, a GH110 domain, a carbohydrate-binding module (CBM) 51 domain, a bacterial Ig-like (Big) 2 domain and a C-terminal transmembrane region, in this order. The recombinant enzyme expressed in Escherichia coli hydrolyzed α1,3-linked Gal in branched blood group B antigen [Galα1-3(Fucα1-2)Galß1-R], but not in a linear xenotransplantation antigen (Galα1-3Galß1-R). The enzyme also acted on group B human salivary mucin and erythrocytes. We also revealed that CBM51 specifically bound blood group B antigen using both isothermal titration calorimetry and a solid-phase binding assay, and it enhanced the affinity of the enzyme toward substrates with multivalent B antigens. We suggest that this enzyme plays an important role in degrading B antigens to acquire nutrients from mucin oligosaccharides in the gastrointestinal tracts.


Subject(s)
Bifidobacterium/enzymology , Escherichia coli/enzymology , Polysaccharides , alpha-Galactosidase , ABO Blood-Group System/metabolism , Blood Group Antigens/isolation & purification , Blood Group Antigens/metabolism , Humans , Infant , Infant, Newborn , Intestines/microbiology , Milk, Human/enzymology , Mucins/chemistry , Mucins/metabolism , Polysaccharides/chemistry , Polysaccharides/metabolism , Receptors, Cell Surface/genetics , Receptors, Cell Surface/isolation & purification , alpha-Galactosidase/genetics , alpha-Galactosidase/isolation & purification , beta-Galactosidase/chemistry , beta-Galactosidase/metabolism
19.
Can J Microbiol ; 58(8): 1002-7, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22827847

ABSTRACT

Vibrio parahaemolyticus is a pathogenic Vibrio species that causes food-borne acute gastroenteritis, often related to the consumption of raw or undercooked seafood. Vibrio parahaemolyticus has 2 type III secretion systems (T3SS1 and T3SS2). Here, we demonstrate that VP1657 (VopB1) and VP1656 (VopD1), which share sequence similarity with Pseudomonas genes popB (38%) and popD (36%), respectively, are essential for translocation of T3SS1 effectors into host cells. A VP1680CyaA fusion reporter system was constructed to observe effector translocation. Using this reporter assay we showed that the VopB1 and VopD1 deletion strains were unable to translocate VP1680 to host cell but that the secretion of VP1680 into the culture medium was not affected. VopB1 or VopD1 deletion strains did not enhance cytotoxicity and failed to activate mitogen-activated protein kinases and secretion of interleukin-8, which depend on VP1680. Thus, we conclude that VopB1 and VopD1 are essential components of the translocon. To target VopB1 and VopD1 may have therapeutic potential for the treatment or prevention in V. parahaemolyticus infection.


Subject(s)
Bacterial Proteins/metabolism , Bacterial Secretion Systems/genetics , Vibrio parahaemolyticus/genetics , Vibrio parahaemolyticus/metabolism , Bacterial Proteins/genetics , Enzyme Activation/genetics , Interleukin-8/metabolism , Mitogen-Activated Protein Kinases/genetics , Mitogen-Activated Protein Kinases/metabolism , Protein Transport/genetics , Sequence Deletion
20.
Biochim Biophys Acta ; 1820(10): 1686-92, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22771831

ABSTRACT

BACKGROUND: Reactive oxygen species (ROS), including superoxide anion radical, induce chronic risk of oxidative damage to many cellular macromolecules resulting in damage to cells. Superoxide dismutases (SODs) catalyze the dismutation of superoxide to oxygen and hydrogen peroxide and are a primary defense against ROS. Vibrio parahaemolyticus, a marine bacterium that causes acute gastroenteritis following consumption of raw or undercooked seafood, can survive ROS generated by intestinal inflammatory cells. However, there is little information concerning SODs in V. parahaemolyticus. This study aims to clarify the role of V. parahaemolyticus SODs against ROS. METHODS: V. parahaemolyticus SOD gene promoter activities were measured by a GFP reporter assay. Mutants of V. parahaemolyticus SOD genes were constructed and their SOD activity and resistance to oxidative stresses were measured. RESULTS: Bioinformatic analysis showed that V. parahaemolyticus SODs were distinguished by their metal cofactors, FeSOD (VP2118), MnSOD (VP2860), and CuZnSOD (VPA1514). VP2118 gene promoter activity was significantly higher than the other SOD genes. In a VP2118 gene deletion mutant, SOD activity was significantly decreased and could be recovered by VP2118 gene complementation. The absence of VP2118 resulted in significantly lowered resistance to ROS generated by hydrogen peroxide, hypoxanthine-xanthine oxidase, or Paraquat. Furthermore, both the N- and C-terminal SOD domains of VP2118 were necessary for ROS resistance. CONCLUSION: VP2118 is the primary V. parahaemolyticus SOD and is vital for anti-oxidative stress responses. GENERAL SIGNIFICANCE: The V. parahaemolyticus FeSOD VP2118 may enhance ROS resistance and could promote its survival in the intestinal tract to facilitate host tissue infection.


Subject(s)
Bacterial Proteins/physiology , Oxidative Stress/physiology , Superoxide Dismutase/physiology , Vibrio parahaemolyticus/physiology , Amino Acid Sequence , Bacterial Proteins/chemistry , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Base Sequence , Drug Resistance, Microbial/genetics , Gene Expression Regulation, Bacterial/physiology , Organisms, Genetically Modified , Oxidative Stress/genetics , Promoter Regions, Genetic , Protein Structure, Tertiary/genetics , Reactive Oxygen Species/metabolism , Reactive Oxygen Species/pharmacology , Sequence Deletion , Superoxide Dismutase/chemistry , Superoxide Dismutase/genetics , Superoxide Dismutase/metabolism , Transcription, Genetic , Vibrio parahaemolyticus/genetics , Vibrio parahaemolyticus/metabolism
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