The effects of selenium,vitamin E and their combination on the composition of fatty acids and proteins in Saccharomyces cerevisiae

The aim of our studies was to test the effect and role of vitamin E and selenium supplements on yeast cell. In this study, the effects of selenium (Se), vitamin E (Vit. E), and their combination (Se plus Vit. E) on the composition of fatty acids and proteins were examined in Saccharomyces cerevisiae strains WET136 and 522. S. cerevisiae cells were grown up in YEPD medium supplemented with Se, Vit. E or their combination. It was found that the level of stearic acid was increased in all supplemented groups (p<0·05; p<0·001). The content of saturated and unsaturated fatty acids was decreased (p<0·05; p<0·01; p<0·001) in Vit. E and Vit. E plus Se supplemented S. cerevisiae. On the other hand, Se alone caused an increase (p<0·001) in the saturated fatty acids but a decrease (p<0·05; p<0·001) in the unsaturated fatty acids. Total proteins in S. cerevisiae were significantly increased (p<0·001) by Vit. E supplement. There was no significant change observed in S. cerevisiae supplemented with Se. These findings indicate that membrane composition of S. cerevisiae is affected by both Vit. E and Se supplements. © 1997 John Wiley & Sons, Ltd.     

Use of in vitro method to evaluate some grapevine varieties for tolerance and susceptibility to sodium bicarbonate-induced chlorosis

Nodal shoot segments of four grapevine genotypes well known for their Fe-chlorosis characteristic [Vitis vinifera × Vitis berlandieri Fercal, resistant; V. berlandieri × Vitis rupestris 1103 P, mid-resistant; Solonis (Vitis riparia × V. rupestris × Vitis candicans) × Othello (Vitis labrusca × V. riparia × V. vinifera) 1613 C, susceptible; V. vinifera L. cv. Perlette, resistant] were cultured in vitro. The effects of three levels of iron sodium ethylene-diaminotetraacetate (FeNaEDTA; 9, 18, 36 mg l⁻¹) and three mixtures of iron and 840 mg l⁻¹ NaHCO₃ (sodium bicarbonate) in the Murashige and Skoog (MS) medium supplemented 4.9 μM indole-3-butyric acid (IBA) were compared. We assayed the chlorosis rating of leaves, total chlorophyll of leaves, dry shoot weights of the plantlets, and active and total Fe content of the leaves. The most suitable concentration in determining the reaction of genotypes to iron chlorosis was 9 mg l⁻¹ FeNaEDTA. Bicarbonate addition had negative effects on the iron intake and development of plants. While all genotypes were affected by non-ferrous conditions, Fercal and Perlette were found to be the most resistant genotypes and 1613 C rootstock as the most susceptible. The chlorosis rating of the tested genotypes ranked according to their known degree of tolerance and susceptibility to lime-induced chlorosis. The results of this study showed that the in vitro technique could successfully be used in viticulture to get results in shorter times in the studies, aiming at breeding new rootstocks and varieties suitable to calcareous soil conditions and determining the reactions of existing genotypes to Fe chlorosis.     

Computational study of the intramolecular proton transfer reactions of 3-hydroxytropolone (2,7-dihydroxycyclohepta-2,4,6-trien-1-one) and its dimers

The proton transfer reaction and dimerization processes of 3-hydroxytropolone (3-OHTRN) have been investigated using density functional theory (DFT) at the B3LYP/6–31+G** level. The influence of the solvent on the proton transfer reaction of 3-OHTRN was examined using the self-consistent isodensity polarized continuum model (SCI-PCM) with different dielectric constants (ε?=?4.9, CHCI₃; ε?=?32.63, CH₃OH; ε?=?78.39, H₂O). The intramolecular proton transfer reaction occurs more readily in the gas phase than in solution. Results also show that the stability of 3-OHTRN dimers in the gas phase is directly affected by the hydrogen bond length in the dimer structure.     

A case of mistaken identity: Lupeol-3-(3′R)-hydroxy-stearate can be mistakenly identified as lupeol acetate when only analyzed by GC–MS

Lupeol-3-(3′R-hydroxy)-stearate, also known as procrim b (1), was isolated from the methanolic stem extract of Pentalinon andrieuxii and initially mistaken as lupeol acetate when analyzed by GC–MS only. The correct structure of 1 was established following a careful analysis of its NMR and MS data.     

Complex Disease Interventions from a Network Model for Type 2 Diabetes

There is accumulating evidence that the proteins encoded by the genes associated with a common disorder interact with each other, participate in similar pathways and share GO terms. It has been anticipated that the functional modules in a disease related functional linkage network are informative to reveal significant metabolic processes and disease’s associations with other complex disorders. In the current study, Type 2 diabetes associated functional linkage network (T2DFN) containing 2770 proteins and 15041 linkages was constructed. The functional modules in this network were scored and evaluated in terms of shared pathways, co-localization, co-expression and associations with similar diseases. The assembly of top scoring overlapping members in the functional modules revealed that, along with the well known biological pathways, circadian rhythm, diverse actions of nuclear receptors in steroid and retinoic acid metabolisms have significant occurrence in the pathophysiology of the disease. The disease’s association with other metabolic and neuromuscular disorders was established through shared proteins. Nuclear receptor NRIP1 has a pivotal role in lipid and carbohydrate metabolism, indicating the need to investigate subsequent effects of NRIP1 on Type 2 diabetes. Our study also revealed that CREB binding protein (CREBBP) and cardiotrophin-1 (CTF1) have suggestive roles in linking Type 2 diabetes and neuromuscular diseases.     

Three new species of ants (genus <Emphasis Type="Italic">Aphaenogaster</Emphasis>, Hymenoptera: Formicidae) from Turkey

Three new species of the ant genus Aphaenogaster (A. aktaci sp. n., A. maculifrons sp. n., A. radchenkoi sp. n.) are described from Turkey and their taxonomic positions are discussed. Aphaenogaster aktaci sp. n. belongs to the obsidiana group, A. maculifrons sp. n. to subterranea group and A. radchenkoi sp. n. to pallida group of the Attomyrma subgenus. Key characteristics for identification of the species and data on their ecology are given.     

Advanced methods for the study of the chemistry and the metabolism of lichens

Lichens are compound entities of a fungal partner (“mycobiont”) and one or more photosynthetically active algae or cyanobacteria (“photobionts”). The organisms live in an intimate, symbiotic association which has been classified as a mutualistic or controlled parasitic relationship. Several metabolites from lichens display unique structures with unknown functions, and only a few model species have been analysed comprehensively. The complex metabolic interplay between the organisms in lichens is also incompletely understood. Earlier experiments with ¹⁴C-labelled precursors indicated that the photobionts produce from CO₂ glucose or sugar alcohols (e.g. ribitol and arabitol) which are then transferred to the mycobionts. In the fungi, these compounds are believed to be converted into mannitol serving as the carbon and energy source in the downstream metabolic processes. Recent methodological developments in spectroscopy and “systems biology” now enable a concise analysis of the metabolite profiles, networks and fluxes by non-targeted quantitative approaches. In this review, we summarize the current knowledge about lichen metabolism and report on the potential of the advanced methods to reinvestigate lichen chemistry and metabolism on a quantitative basis.     

Immobilization of nisin producer Lactococcus lactis strains to chitin with surface-displayed chitin-binding domain

In this study, nisin producer Lactococcus lactis strains displaying cell surface chitin-binding domain (ChBD) and capable of immobilizing to chitin flakes were constructed. To obtain ChBD-based cell immobilization, Usp45 signal sequence with ChBD of chitinase A1 enzyme from Bacillus circulans was fused with different lengths of PrtP (153, 344, and 800 aa) or AcmA (242 aa) anchors derived from L. lactis. According to the whole cell ELISA analysis, ChBD was successfully expressed on the surface of L. lactis cells. Scanning electron microscope observations supported the conclusion of the binding analysis that L. lactis cells expressing the ChBD with long PrtP anchor (800 aa) did bind to chitin surfaces more efficiently than cells with the other ChBD anchors. The attained binding affinity of nisin producers for chitin flakes retained them in the fermentation during medium changes and enabled storage for sequential productions. Initial nisin production was stably maintained with many cycles. These results demonstrate that an efficient immobilization of L. lactis cells to chitin is possible for industrial scale repeated cycle or continuous nisin fermentation.     

Investigation of the effects of α-tocopherol on the levels of Fe,Cu, Zn,Mn, and carbonic anhydrase in rats with bleomycin-induced pulmonary fibrosis

This study was designed to examine the effects of vitamin E on the levels of Zn, Mn, Cu, Fe, and carbonic anhydrase in rats with bleomycin-induced pulmonary fibrosis. Twenty-one male Wistar albino rats were randomly divided into three groups: bleomycin alone, bleomycin+vitamin E, and saline alone (control group). The bleomycin group was given 7.5 mg/kg body weight (single dose) bleomycin hydrochloride intratracheally. The bleomycin+vitamin E group was also instilled with bleomycin hydrochloride but received injections of α-tocopherol twice a week. The control group was treated with saline alone. Animals were sacrified 14 d after intratracheal instillation of bleomycin. Tissue Zn, Mn, Cu, Fe, and carbonic anhydrase activities were measured in the lung and liver. Lung Cu, Fe, and carbonic anhydrase activity increase in both experimental groups. Zn and Mn levels decreased, except for the Mn level in the bleomycin group. Liver Zn, Mn, and Cu levels decreased in both experimental groups compared to the control group, whereas Fe and carbonic anhydrase activity increased in comparison to the control group. However, the liver tissue Fe level decreased compared to the control group. In the histopathologic assesment of lung sections in the bleomycin+vitamin E group, partial fibrotic lesions were observed, but the histopathologic changes were much less severe compared to the bleomycin-treated group.