Saccharomyces yeasts degrade sugars to two-carbon components, in particular ethanol, even in the presence of excess oxygen. This characteristic is called the Crabtree effect and is the background for the 'make–accumulate–consume' life strategy, which in natural habitats helps Saccharomyces yeasts to out-compete other microorganisms. A global promoter rewiring in the Saccharomyces cerevisiae lineage, which occurred around 100 mya, was one of the main molecular events providing the background for evolution of this strategy. Here we show that the Dekkera bruxellensis lineage, which separated from the Saccharomyces yeasts more than 200 mya, also efficiently makes, accumulates and consumes ethanol and acetic acid. Analysis of promoter sequences indicates that both lineages independently underwent a massive loss of a specific cis-regulatory element from dozens of genes associated with respiration, and we show that also in D. bruxellensis this promoter rewiring contributes to the observed Crabtree effect.

Medical plants and their various extracts have been occasionally used in the treatment of many diseases. Astragalus is one of those medical plants and it has several biological activities. In the present study, the hexane extracts of six Astragalus species, which are grown in the eastern Anatolia region of Turkey, were isolated, and their mutagenic and antimutagenic properties were investigated by using Salmonella typhimurium TA1535, TA1537 and Escherichia coli WP2uvrA tester strains at 0.05, 0.5 and 5 microg/plate concentrations. Known mutagens sodium azide (NaN(3)), 9-Aminoacridine (9-AA) and N-Methyl-N'-nitro-N-nitrosoguanidine (MNNG) were used to determine antimutagenic properties of hexane extracts. The results showed that all hexane extracts, investigated in the present study, can be considered genotoxically safe because they do not have mutagenic activity at the tested concentrations. But, a great many of them have antimutagenic activity against 9-Aminoacridine known as a model intercalator agent. The inhibition rates obtained from the antimutagenicity assays ranged from 27.51% (A. macrocephalus--0.05 microg/plate) to 54.39% (A. galegiformis--5 microg/plate). These activities are valuable toward an extension of the employ of these drugs as new phytotherapeutic or preservative ingredients.

In the current study, 18 halotolerant and halophilic bacteria have been investigated for their plant growth promoting abilities in vitro and in a hydroponic culture. The bacterial strains have been investigated for ammonia, indole-3-acetic acid and 1-aminocyclopropane-1-carboxylate-deaminase production, phosphate solubilisation and nitrogen fixation activities. Of the tested bacteria, eight were inoculated with Triticum aestivum in a hydroponic culture. The investigated bacterial strains were found to have different plant-growth promoting activities in vitro. Under salt stress (200 mM NaCl), the investigated bacterial strains significantly increased the root and shoot length and total fresh weight of the plants. The growth rates of the plants inoculated with bacterial strains ranged from 62.2% to 78.1%.Identifying of novel halophilic and halotolerant bacteria that promote plant growth can be used as alternatives for salt sensitive plants. Extensive research has been conducted on several halophilic and halotolerant bacterial strains to investigate their plant growth promoting activities. However, to the best of my knowledge, this is the first study to inoculate these bacterial strains with wheat.

Mentha is a medicinal and aromatic plant belonging to the Lamiaceae family, which is widely used in food, flavor, cosmetic and pharmaceutical industries. Recently, it has been found that the use of Mentha as a pharmaceutical source is based on its phytochemical constituents that have far been identified as tannins, saponins, phenolic acids and flavonoids. This study was designed to evaluate the mutagenic and antimutagenic activities of apigenin 7-O-glucoside (A7G), a flavonoid isolated from Mentha longifolia (L.) Hudson subspecies longifolia (ML). The possible antimutagenic potential of A7G was examined against mutagens ethyl methanesulfonate and acridine in an eukaryotic cell system Saccharomyces cerevisiae and sodium azide in Salmonella typhimurium TA1535 and 9-aminoacridine in S. typhimurium TA1537. According to our findings, any concentrations of the A7G used did not show mutagenic activity but exerted strong antimutagenic activities at tested concentrations. The inhibition rates for the Ames test ranged from 27.2% (S. typhimurium TA1535: 0.4 μM/plate) to 91.1% (S. typhimurium TA1537: 0.2 μM/plate) and for the yeast deletion assay from 4% to 57.7%. This genotoxicological study suggests that a flavonoid from ML owing to antimutagenic properties is of great pharmacological importance and might be beneficial to industries producing food additives, cosmetics and pharmaceuticals products.

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For ages, lichens have long been investigated popularly for biological roles, mainly antitumor, antimicrobial and antioxidant activities. Many positive results were obtained in these previous research. Thus, in this study, we aimed to determine whether extracts of Usnea articulata (UAE) and Usnea filipendula (UFE) possessing a protection against aflatoxin B1 (AFB1)-induced genotoxic and oxidative damage. The results of our studies showed that 5 μM concentrations of AFB1 increased the frequencies of sister chromatid exchange (SCE) and the level of malondialdehyde (MDA) and decreased the activities of superoxide dismutase (SOD), glutathione (GSH) and glutathione peroxidase (GPx). However, when 5, 10 and 20 µg/mL concentrations of UAE and UFE was added to AFB1, the frequencies of SCE and MDA level were decreased and SOD, GSH and GPx level were increased. The Ames (Salmonella typhimurium TA1535, TA1537) and WP2 (Escherichia coli) test systems carried out evinced that UAE and UFE possess any mutagenicity, but have antimutagenic effects. Consequently, the results of this experiment have clearly shown that UAE and UFE have strong antioxidative and antigenotoxic effects that are associated with its antioxidant nature. A detailed study can be performed to determine the antioxidant properties of each compound that will extend the use of lichen extracts in food and pharmacy industries.

In this article, the genotoxic and antigenotoxic effects of methanol extract of of Cladonia foliacea (Huds.) Willd. (CME) were studied using WP2, Ames (TA1535 and TA1537), and sister chromatid exchange (SCE) test systems. The results of our studies showed that 5 µM concentration of aflatoxin B1(AFB1) changed the frequencies of SCE and malondialdehyde (MDA) levels, superoxide dismutase (SOD), glutathione (GSH), and glutathione peroxidase (GPx) activities. When 5 and 10 µg/mL concentrations of CME was added to AFB1, the frequencies of SCE and MDA level were decreased and SOD, GSH, and GPx levels were increased. The extract CME did not show any mutagenicity on Ames (Salmonella typhimurium TA1535, TA1537) and WP2 (Escherichia coli) test systems. On the other hand, CME has antimutagenicity on the mentioned test systems. The results of this experiment have clearly shown that CME has a significant antioxidative and antigenotoxic effect, which is thought to be due to the antigenotoxic activities of antioxidant enzymes.

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