Proteinase A-like enzyme from germinated kidney bean seeds. Its action on phaseolin and vicilin

A cysteine proteinase that possibly participates in the degradation of phaseolin, the main storage protein of kidney bean ( Phaseolus vulgaris L. cv. Moldavian) was isolated from germinating kidney bean seeds and partially characterized. According to its properties it may be classified as a member of a group of homologous cysteine proteinases A, also present in germinating seeds of a number of other plants. The proteinase of this group hydrolyze storage proteins to short peptides. Similarly, the kidney bean proteinase hydrolyzes vicilin, the reserve protein of vetch ( Vicia sativa ). However, its action on phaseolin is limited to the cleavage of subunits into two approximately equal parts and to the splitting off a small number of short peptides. An explanation of phaseolin resistance to the action of this proteinase is proposed on the basis of the differences of its structure from that of other homologous 7S proteins.     

Corrections by melatonin of liver mitochondrial disorders under diabetes and acute intoxication in rats

The aim of the present work was to investigate the mechanisms of oxidative damage of the liver mitochondria under diabetes and intoxication in rats as well as to evaluate the possibility of corrections of mitochondrial disorders by pharmacological doses of melatonin. The experimental (30 days) streptozotocin‐induced diabetes mellitus caused a significant damage of the respiratory activity in rat liver mitochondria. In the case of succinate as a respiratory substrate, the ADP‐stimulated respiration rate V₃ considerably decreased (by 25%, p < 0·05) as well as the acceptor control ratio (ACR) V₃/V₂ markedly diminished (by 25%, p < 0·01). We observed a decrease of the ADP‐stimulated respiration rate V₃ by 35% (p < 0·05), with glutamate as substrate. In this case, ACR also decreased (by 20%, p < 0·05). Surprisingly, the phosphorylation coefficient ADP/O did not change under diabetic liver damage. Acute rat carbon tetrachloride‐induced intoxication resulted in considerable decrease of the phosphorylation coefficient because of uncoupling of the oxidation and phosphorylation processes in the liver mitochondria. The melatonin administration during diabetes (10 mg·kg^‐1 body weight, 30 days, daily) showed a considerable protective effect on the liver mitochondrial function, reversing the decreased respiration rate V₃ and the diminished ACR to the control values both for succinate‐dependent respiration and for glutamate‐dependent respiration. The melatonin administration to intoxicated animals (10 mg·kg⁻¹ body weight, three times) partially increased the rate of succinate‐dependent respiration coupled with phosphorylation. The impairment of mitochondrial respiratory plays a key role in the development of liver injury under diabetes and intoxication. Melatonin might be considered as an effector that regulates the mitochondrial function under diabetes. Copyright © 2011 John Wiley & Sons, Ltd.     

Impact of Soil Cadmium on Land Snails: A Two-Stage Exposure Approach under Semi-Field Conditions Using Bioaccumulative and Conchological End-Points of Exposure

Land snails are highly tolerant to cadmium exposure and are able to accumulate soil cadmium independently of food ingestion. However, little information exists on the kinetics of cadmium retention in terrestrial gastropods exposed to an increase in the soil cadmium content, over time. There is also little knowledge about how exposure to cadmium-polluted soils influences shell growth and architecture. In this context, we examined cadmium accumulation in the hepatopancreas and shell of juvenile Cantareus aspersus exposed to elevating high levels of cadmium in soil. Also, the toxicity of cadmium to snails was assessed using a range of conchological endpoints, including shell height, width, volume, allometry and integrity. Test snails, aged three months, were reared under semi-field conditions, fed an uncontaminated diet and exposed first, for a period of 30 days, to a series of soil cadmium concentrations, and then, for a second period of 30 days, to soils with higher cadmium content. Cadmium showed a dose-dependent accumulation in both the hepatopancreas and shell. The kinetics of cadmium retention in the hepatopancreas of snails previously exposed to cadmium-spiked soils was significantly influenced by a new exposure event. The shell was not a relevant bioaccumulator for soil cadmium. Under the present experimental conditions, only high cadmium exposure significantly affected either the shell growth or snail survival. There was no consistent effect on shell allometry, but the shell integrity, especially in rapidly growing parts, appeared to be affected by high cadmium exposure. Our results attest to the value of hepatopancreas for describing cadmium retention in land snails and to the difficulty of using conchological parameters in field surveys for estimating the environmental hazard of soil cadmium.     

Physicochemical modelling of the classical steelmaking route for life cycle inventory analysis

Goal, scope and background  

Integrating environmental issues into the traditional product design process, for powerful eco-efficiency, is now one of the major priorities for steelmakers. Life cycle assessment (LCA) is currently undertaken as the most holistic approach for assessing environmental impact and selecting new technologies to reduce emissions for steel industry. However, in order to identify new ways for environmental friendly production of steel, it is essential to carry out the process Life cycle inventory (LCI) which is the core part of LCA. According to LCA practitioners, the quality and the availability of data are the main important limiting factors when applying this methodology for new steelmaking processes without large industrial application. In this paper, we propose a new approach of LCIA of steelmaking, based on the simulation of traditional processes which guarantees the quality of data, the mass and the energy balances. This approach is validated for an existing integrated plant and will be used to assess the inventory for breakthrough steelmaking technologies.     

First-trimester diagnosis on chorionic villi obtained by direct vision technique

Summary An improved technique for direct vision chrionic biopsy that gives a clear view of the amniotic sac was developed. With this technique, used in 48 women prior to vacuum aspiration and in six cases for diagnosis (karyotyping or enzyme analysis), it was possible to obtain chorionic villi free from contamination by maternal tissue. It was also possible to pick out villi (rich in blood vessels and with abundant buds on their surface) found to be most capable of growing in vitro. In the diagnostic cases, the pregnancies have continued uneventfully since the sampling; one pregnancy is now in the 32nd week.     

The Diverged Trypanosome MICOS Complex as a Hub for Mitochondrial Cristae Shaping and Protein Import

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Knowledge-based computational mutagenesis for predicting the disease potential of human non-synonymous single nucleotide polymorphisms

Certain genetic variations in the human population are associated with heritable diseases, and single nucleotide polymorphisms (SNPs) represent the most common form of such differences in DNA sequence. In particular, substantial interest exists in determining whether a non-synonymous SNP (nsSNP), leading to a single residue replacement in the translated protein product, is neutral or disease-related. The nature of protein structure-function relationships suggests that nsSNP effects, either benign or leading to aberrant protein function possibly associated with disease, are dependent on relative structural changes introduced upon mutation. In this study, we characterize a representative sampling of 1790 documented neutral and disease-related human nsSNPs mapped to 243 diverse human protein structures, by quantifying environmental perturbations in the associated proteins with the use of a computational mutagenesis methodology that relies on a four-body, knowledge-based, statistical contact potential. These structural change data are used as attributes to generate a vector representation for each nsSNP, in combination with additional features reflecting sequence and structure of the corresponding protein. A trained model based on the random forest supervised classification algorithm achieves 76% cross-validation accuracy. Our classifier performs at least as well as other methods that use significantly larger datasets of nsSNPs for model training, and the novelty of our attributes differentiates the model as an orthogonal approach that can be utilized in conjunction with other techniques. A dedicated server for obtaining predictions, as well as supporting datasets and documentation, is available at http://proteins.gmu.edu/automute.