Comparative proteomics and immunoproteomics of Helicobacter pylori related to different gastric pathologies

Helicobacter pylori is a Gram-negative bacterium which causes ulcer, atrophic gastritis, adenocarcinoma, or mucosa-associated lymphoid tissue lymphoma. A comparative proteomic and immunoproteomic analysis was chosen to identify the antigenic patterns of three different H. pylori strains. These strains were probed against single sera from H. pylori-positive patients affected by gastric adenocarcinoma or duodenal ulcer. We found a quite heterogeneous antigenic pattern, both from strain and sera points of view, thus underlying both a strain- and a host-specificity. The different antigenic repertoires introduced the importance of the strain to be used for immunoblotting as a diagnostic test.     

Molecular phylogeny of the blind cavefish <Emphasis Type="Italic">Phreatichthys andruzzii</Emphasis> and <Emphasis Type="Italic">Garra barreimiae</Emphasis> within the family Cyprinidae

The phylogenetic relationships of two cavefish, Phreatichthys andruzzii and Garra barreimiae, belonging to the family Cyprinidae, were investigated by sequencing the mitochondrial cytochrome b gene. These cavefish species are native to Somalia (eastern Africa) and Oman (southeastern Arabian peninsula), respectively, and so far no molecular support to their taxonomy and phylogenetic position was ever provided. The analysis of cytochrome b sequences showed that the species are monophyletic taxa, closely related to each other and to other species of the genus Garra. Molecular clock calculations allowed to date the origin of these hypogaean species back to the Plio-Pleistocene and support the hypothesis that African cyprinids originated from Miocenic immigrations of Asian ancestors.     

Characterization of hairy root-phenotype in transgenic <Emphasis Type="Italic">Hypericum perforatum</Emphasis> L. clones

Hairy root-regenerated clones of Hypericum perforatum L. grown in vitro similarly to those successfully adapted to ex vitro conditions showed phenotype features typical for plants transformed with Agrobacterium rhizogenes T-DNA. These included reduced apical dominance, increased branching, dwarfing and reduced fertility. Transgenic clones differed in ability to develop root system as a necessary condition for transfer to the soil. One of the profiling characters, capability of hypericin biosynthesis was altered as well. Dark glands as the sites of hypericin accumulation and/or synthesis exhibited significantly higher densities on both, leaves and petals of transgenic clones comparing to controls. In the genome of transgenic clones, rolABC genes were detected. Both clones harboured similar copy number of individual rol genes. However, copy numbers descended from rolA to rolC gene in both clones.     

Effect of culture age, protectants, and initial cell concentration on viability of freeze-dried cells of Metschnikowia pulcherrima

The effect of freeze-drying using different lyoprotectants at different concentrations on the viability and biocontrol efficacy of Metschnikowia pulcherrima was evaluated. The effects of initial yeast cell concentration and culture age on viability were also considered. Yeast cells grown for 36 h were more resistant to freeze-drying than were 48 h cells. An initial concentration of 10? cells·mL?1 favoured the highest survival after freeze-drying. When maltose (25%, m/v) was used as protectant, a high cell viability was obtained (64.2%). Cells maintained a high viability after 6 months of storage at 4 °C. The biocontrol efficacy of freeze-dried cells was similar to the activity of fresh cells on 'Gala' apples and was slightly lower on 'Golden Delicious' apples. After optimizing freeze-drying conditions, the viability of M. pulcherrima cells was similar to that obtained in other studies. The results constitute a first step towards the commercial development of M. pulcherrima as a biocontrol agent.     

Proteomic and redox‐proteomic evaluation of homogentisic acid and ascorbic acid effects on human articular chondrocytes

Alkaptonuria (AKU) is a rare genetic disease associated with the accumulation of homogentisic acid (HGA) and its oxidized/polymerized products in connective tissues up to the deposition of melanin‐like pigments (ochronosis). Since little is known on the effects of HGA and its metabolites on articular cells, we carried out a proteomic and redox‐proteomic analysis to investigate how HGA and ascorbic acid (ASC) affect the human chondrocytic protein repertoire. We settled up an in vitro model using a human chondrocytic cell line to evaluate the effects of 0.33 mM HGA, alone or combined with ASC. We found that HGA and ASC significantly affect the levels of proteins with specific functions in protein folding, cell organization and, notably, stress response and cell defense. Increased protein carbonyls levels were found either in HGA or ASC treated cells, and evidences produced in this paper support the hypothesis that HGA‐induced stress might be mediated by protein oxidation. Our finding can lay the basis towards the settling up of more sophisticated models to study AKU and ochronosis. J. Cell. Biochem. 111: 922–932, 2010. © 2010 Wiley‐Liss, Inc.     

Prognostic potential of precise molecular diagnosis of Autosomal Recessive Osteopetrosis with respect to the outcome of bone marrow transplantation

Hematopoietic stem cell transplantation (HSCT) is often the only practical approach to fatal genetic defects. One of the first pathologies which HSCT was applied to was Autosomal Recessive Osteopetrosis (ARO), a rare genetic bone disease in which a deficit in bone resorption by osteoclasts leads to increased bone density and secondary defects. The disease is often lethal early in life unless treated with HSCT. In utero transplantation (IUT) of the oc/oc mouse, reproducing the clinical features of a subset of ARO, has demonstrated that the quality of life and the survival of transplanted animals are greatly improved, suggesting that a similar protocol could be applied to humans. However, recently the dissection of the molecular bases of the disease has shown that ARO is genetically heterogeneous and has revealed the presence of subsets of patients which do not benefit from HSCT. This observation highlights the importance of molecular diagnosing ARO to identify and establish the proper therapies for a better prognosis. In particular, on the basis of experimental results in murine models, efforts should be undertaken to develop approaches such as IUT and new pharmacological strategies.     

Haemagglutination and surface structures in strains of Clostridium spiroforme

The low heat resistance (D100 = 0.554 min, z = 13.4 degrees C) of dormant lysozyme-sensitized spores of Bacillus sphaericus 9602 was correlated with a low protoplast wet density (1.305 g/ml) equivalent to a high protoplast water content (61.0%, wet weight basis). These values for these unusual spores were consistent with those correlated previously in 28 spore types of seven other species.     

Salinity-induced limits to mangrove canopy height

Aim

Mangrove canopy height is a key metric to assess tidal forests' resilience in the face of climate change. In terrestrial forests, tree height is primarily determined by water availability, plant hydraulic design, and disturbance regime. However, the role of water stress remains elusive in tidal environments, where saturated soils are prevalent, and salinity can substantially affect the soil water potential.

Location

Global.

Time Period

The canopy height dataset provides a global snapshot of the maximum mangrove height geographical distribution for the year 2000. Climate and environmental variables extend over the period 1970–2018.

Major Taxa Studied

Mangroves.

Methods

We use global observations of maximum canopy height, species richness, air temperature, and seawater salinity—a proxy of soil water salt concentration—to explore the causal link between salinity and mangrove stature.

Results

Our findings suggest that salt stress limits mangrove height. High salinity favours more salt-tolerant species, narrowing the spectrum of viable traits. Highly salt-tolerant mangroves have evolved to cope with high salt concentrations in the soil, but this adaptation comes at a cost. They typically have lower rates of photosynthesis and growth, resulting in reduced productivity and smaller stature compared to more salt-sensitive mangrove species. This suggests a causal link between salinity, biodiversity, and tree height, where high salinity selects for more salt-tolerant species that tend to be less productive and shorter.

Conclusions

We hypothesize that the salinity-induced limit to mangrove canopy height is the direct result of a reduction of primary productivity, an increment in the risk of xylem cavitation, and an indirect consequence of the decrease in biodiversity. As sea-level rise enhances coastal salinisation, failure to account for these effects can lead to incorrect estimates of future carbon stocks in Tropical coastal ecosystems and endanger preservation efforts.