Large-scale methylation patterns in the nuclear genomes of plants.

Methylation was investigated in compositional fractions of nuclear DNA preparations (50-100 kb in size) from five plants (onion, maize, rye, pea and tobacco), and was found to increase from GC-poor to GC-rich fractions. This methylation gradient showed different patterns in different plants and appears, therefore, to represent a novel, characteristic genome feature which concerns the noncoding, intergenic sequences that make up the bulk of the plant genomes investigated and mainly consist of repetitive sequences. The structural and functional implications of these results are discussed.     

Structural and ultrastructural modifications following transurethral injection of teflon paste

Structural and ultrastructural tissue modifications caused by polytetrafluoroethylene (teflon) paste injection in incontinent male patients have been studied. The most considerable observations are: a diffuse interstitial splitting of teflon paste in particles of about 3-100 microns. Given that the tissue reaction is limited to a modest infiltration of lymphocytes and monocytes and a slight increase in the collagen fibres, it is concluded that the teflon paste injection is well tolerated by the tissues.     

Isatin: a privileged scaffold for the design of carbonic anhydrase inhibitors

The isatin scaffold is the constitutive fragment of several natural and synthetic bioactive molecules. Albeit several benzene sulphonamide-based carbonic anhydrase inhibitors (CAIs) have been reported, only recently isatin benzene sulphonamides have been studied and proposed as CAIs. In this study we have designed, synthesised, and evaluated the biological activity of a series of differently substituted isatin-based benzene sulphonamides which have been designed for the inhibition of carbonic anhydrase isoforms. The activity of all the synthesised compounds was evaluated towards human carbonic anhydrase I, II, IX, and XII isozymes. Our results indicate that the nature and position of substituents on the isatin ring can modulate both activity and isozyme selectivity.     

Photosynthetic generation of heterologous terpenoids in cyanobacteria

The work aims to convert the secondary slow metabolism of the terpenoid biosynthetic pathway into a primary activity in cyanobacteria and to generate heterologous products using these photosynthetic microorganisms as cell factories. Case study is the production of the 10-carbon monoterpene β-phellandrene (PHL) in Synechocystis sp. PCC 6803 (Synechocystis). Barriers to this objective include the slow catalytic activity of the terpenoid metabolism enzymes that limit rates and yield of product synthesis and accumulation. “Fusion constructs as protein overexpression vectors” were applied in the overexpression of the geranyl diphosphate synthase (GPPS) and β-phellandrene synthase (PHLS) genes, causing accumulation of GPPS up to 4% and PHLS up to 10% of the total cellular protein. Such GPPS and PHLS protein overexpression compensated for their slow catalytic activity and enabled transformant Synechocystis to constitutively generate 24 mg of PHL per g biomass (2.4% PHL:biomass, w-w), a substantial improvement over earlier yields. The work showed that a systematic overexpression, at the protein level, of the terpenoid biosynthetic pathway genes is a promising approach to achieving high yields of prenyl product biosynthesis, on the way to exploiting the cellular terpenoid metabolism for commodity product generation.     

Risk assessment does not explain high prevalence of gestational diabetes mellitus in a large group of Sardinian women

Background  

A very high prevalence (22.3%) of gestational diabetes mellitus (GDM) was recently reported following our study on a large group of Sardinian women. In order to explain such a high prevalence we sought to characterise our obstetric population through the analysis of risk factors and their association with the development of GDM.     

Visualization and characterization of Enterococcus faecalis biofilm structure in bovine dentin using 2D and 3D microscopic techniques

Archives of Microbiology - Bacterial biofilms are related to various dental and periodontal infectious diseases, and the characterization of this biological structure with micro-computed tomography...     

Heterologous synthesis of geranyllinalool,a diterpenol plant product,in the cyanobacterium Synechocystis

Cyanobacteria are industrially robust photosynthetic microorganisms that can be genetically programmed to synthesize commodity products for domestic and industrial consumption. In the present work, Synechocystis was endowed with the synthesis of the plant secondary metabolite geranyllinalool, a diterpene alcohol of commercial interest. Total average yields of 360 μg of geranyllinalool per gram of dry cell weight were obtained in the course of a 48-h cultivation period. Geranyllinalool was primarily sequestered inside the transformant cells, corresponding to 60–70% of the total heterologous product, instead of being entirely exuded, as the case is with shorter heterologous terpene hydrocarbons. Extraction of geranyllinalool necessitated disruption of the cells in order to release and isolate this chemical product. Moreover, geranyllinalool accumulation in the cells caused a mild inhibitory effect on cell fitness and biomass growth rate, such that the duplication time of Synechocystis transformants was 1.4-fold longer than that of the control. The remaining 30–40% of the geranyllinalool product was found to float on the surface of sealed transformant cultures, where it was siphoned off by applying a hydrophobic overlayer, with no need to disrupt the cells in this case. Concluding, the work extended efforts to heterologously produce terpene and terpenol products in cyanobacteria, and addressed possibilities and constrains inherent to this production system.