Resistance and bioaccumulation of Cd2+, Cu2+, Co2+ and Mn2+ by thermophilic bacteria, Geobacillus thermantarcticus and Anoxybacillus amylolyticus

In this study, bioaccumulation and heavy metal resistance of Cd²⁺, Cu²⁺, Co²⁺ and Mn²⁺ ions by thermophilic Geobacillus thermantarcticus and Anoxybacillus amylolyticus was investigated. The bacteria, in an order with respect to metal resistance from the most resistant to the most sensitive, was found to be Mn²⁺ > Co²⁺ > Cu²⁺ > Cd²⁺ for both G. thermantarcticus and A. amylolyticus. It was determined that the highest metal bioaccumulation was performed by A. amylolyticus in Mn²⁺ (28,566 μg/g dry weight), and the lowest metal bioaccumulation was performed by A. amylolyticus in Co²⁺ (327.3 μg/g dry weight). The highest Cd²⁺ capacities of dried cell membrane was found to be 36.07 and 39.55 mg/g membrane for G. thermantarticus and A. amylolyticus, respectively, and the highest Cd²⁺ capacities of wet cell membrane was found to be 14.36 and 12.39 mg/g membrane for G. thermantarcticus and A. amylolyticus, respectively.     

Characterization of two genes encoding metal tolerance proteins from Beta vulgaris subspecies maritima that confers manganese tolerance in yeast

Manganese (Mn²⁺) is an essential micronutrient in plants. However increased Mn²⁺ levels are toxic to plant cells. Metal tolerance proteins (MTPs), member of cation diffusion facilitator protein (CDF) family, have important roles in metal homeostatis in different plant species and catalyse efflux of excess metal ions. In this study, we identified and characterized two MTP genes from Beta vulgaris spp. maritima (B. v. ssp. maritima). Overexpression of these two genes provided Mn tolerance in yeast cells. Sequence analyses displayed BmMTP10 and BmMTP11as members of the Mn-CDF family. Functional analyses of these proteins indicated that they are specific to Mn²⁺ with a role in reducing excess cellular Mn²⁺ levels when expressed in yeast. GFP-fusion constructs of both proteins localized to the Golgi apparatus as a punctuated pattern. Finally, Q-RT-PCR results showed that BmMTP10 expression was induced threefold in response to the excess Mn²⁺ treatment. On the other hand BmMTP11 expression was not affected in response to excess Mn²⁺ levels. Thus, our results suggest that the BmMTP10 and BmMTP11 proteins from B. v. ssp. maritima have non-redundant functions in terms of Mn²⁺ detoxification with a similar in planta localization and function as the Arabidopsis Mn-CDF homolog AtMTP11 and this conservation shows the evolutionary importance of these vesicular proteins in heavy metal homeostatis among plant species.     

Whole-body exposure of radiation emitted from 900 MHz mobile phones does not seem to affect the levels of anti-apoptotic bcl-2 protein

The purpose of the present study was to investigate the anti-apoptotic bcl-2 protein in rat brain and testes after whole-body exposure to radiation emitted from 900 MHz cellular phones. Two groups (sham and experimental) of Sprague-Dawley rats of eight rats each were used in the study. Exposure began approximately 10 min after transferring into the exposure cages, a period of time when rats settled down to a prone position and selected a fixed location inside the cage spontaneously. For the experimental group, the phones were in the speech condition for 20 min per day for 1 month. The same procedure was applied to the sham group rats, but the phones were turned off. Immunohistochemical staining of bcl-2 was performed according to the standardized avidin-biotin complex method. The results of this study showed that 20 min of the radiation emitted from 900 MHz cellular phones did not alter anti-apoptotic bcl-2 protein in the brain and testes of rats. We speculate that bcl-2 may not be involved in the effects of radiation on the brain and testes of rats.     

Is my footprint too big? Exploring the ecological footprint concept with high school students

The ecological footprint concept is important in order to evaluate the human impact on the environment and propose sustainable solutions in our life. By calculating ecological footprint, people could analyze the impact of their lifestyle on the natural environment. The purpose of this study is to share an ecological footprint education module for high school students in order to increase their awareness and understanding related to this concept. This module included theoretical and activity parts and was applied to 140 ninth-grade high school students. Through the activity, students could understand the connection between ecological footprint, bio-capacity, and population and explore how our actions influence our ecological footprint and bio-capacity. Teachers could adapt this ecological footprint education module so that their students could understand the connection between human activities and earth systems.     

An Ethnobotanical survey of the beypazari, ayas, and Güdül district towns of Ankara Province (Turkey)

Dietary, therapeutical, and other ethnobotanical uses of the wild plants grown in the Beypazari, Aya§, and Güdül district towns of Ankara were investigated. Information was collected by oral interviews, with 400 individuals participating in 25 selected sites. The demographic characteristics of the informants were cross-linked with the recorded plant data for purposes of statistical analysis by SPSS software. The results indicated that 82% of the informants recognized the use of wild plants for food and home remedies. Both the breadth and scope of knowledge on the use of wild plants increased significantly with the advancing age of the informants, but there was no significant correlation between the knowledge of the informants and their educational status. Altogether, the authors recorded 192 uses for wild plants in the surveyed area; these emanating from 85 plant species belonging to 31 plant families. Among the most popular uses for wild plants were for medicines (115 citations) or food (70 citations). Only 7 plants fell in the miscellaneous category.     

Cd, Cu, Ni, Mn and Zn resistance and bioaccumulation by thermophilic bacteria, Geobacillus toebii subsp. decanicus and Geobacillus thermoleovorans subsp. stromboliensis

Bioaccumulation and heavy metal resistance of Cd²⁺, Cu²⁺, Ni²⁺, Zn²⁺ and Mn²⁺ ions by thermophilic Geobacillus toebii subsp. decanicus and Geobacillus thermoleovorans subsp. stromboliensis were investigated. The metal resistance from the most resistant to the most sensitive was found as Mn > Ni > Cu > Zn > Cd for both Geobacillus thermoleovorans subsp. stromboliensis and Geobacillus toebii subsp. decanicus. It was determined that the highest metal bioaccumulation was performed by Geobacillus toebii subsp. decanicus for Zn (36,496 μg/g dry weight cell), and the lowest metal bioaccumulation was performed by Geobacillus toebii subsp. decanicus for Ni (660.3 μg/g dry weight cell). Moreover, the dead cells were found to biosorbe more metal in their membranes compared to the live cells. In the presence of 7.32 mg/l Cd concentration, the levels of Cd absorbed in live and dead cell membranes were found as 17.44 and 46.2 mg/g membrane, respectively.