Response to Martin and colleagues: mitochondria do not boost the bioenergetic capacity of eukaryotic cells

A recent paper by (Gerlitz et al., Biol Direct 13:21, 2018) questions the validity of the data underlying prior analyses on the bioenergetics capacities of cells, and continues to promote the idea that the mitochondrion endowed eukaryotic cells with energetic superiority over prokaryotes. The former point has been addressed previously, with no resultant changes in the conclusions, and the latter point remains inconsistent with multiple lines of empirical data.     

Potential of ligninolytic enzymatic complex produced by white‐rot fungi from genus Trametes isolated from Bulgarian forest soil

Because of the crucial role of ligninolytic enzymes in a variety of industrial processes, the demand for a new effective producer has been constantly increasing. Furthermore, information on enzyme synthesis by autochthonous fungal strains is very seldom found. Two fungal strains producing ligninolytic enzymes were isolated from Bulgarian forest soil. They were identified as being Trametes trogii and T. hirsuta. These two strains were assessed for their enzyme activities, laccase (Lac), lignin peroxidase (LiP) and Mn‐dependent peroxidase (MnP) in culture filtrate depending on the temperature and the type of nutrient medium. T. trogii was selected as the better producer of ligninolytic enzymes. The production process was further improved by optimizing a number of parameters such as incubation time, type of cultivation, volume ratio of medium/air, inoculum size and the addition of inducers. The maximum activities of enzymes synthesized by T. trogii was detected as 11100 U/L for Lac, 2.5 U/L for LiP and 4.5 U/L for MnP after 14 days of incubation at 25°C under static conditions, volume ratio of medium/air 1:6, and 3 plugs as inoculum. Among the supplements tested, 5% glycerol increased Lac activity to a significant extent. The addition of 1% veratryl alcohol had a positive effect on MnP.     

Microbiological dehydrogenation of polyfunctional Δ5-3β-acetoxy steroids by Corynebacterium mediolanum strain B-964

Summary A high-yield microbiological transformation of polyfunctional ⁵-3-acetoxy steroids, containing an additional ring E, by Corynebacterium mediolanum strain B-964 was carried out, resulting in the corresponding ⁴-3-ketones. It was shown that the type of transformation and the yield of the reaction depend on the degree of saturation of the ring E and on the position of the oxygen-containing substituents in it.     

Effects of a range expansion on adaptive and neutral genetic diversity in dispersal limited Hazel grouse (<Emphasis Type="Italic">Bonasa bonasia</Emphasis>) in the French Alps

Biogeographic range expansions, when related to dispersal limitation, may have counter intuitive effects on genetic diversity. At range margins the relative roles of demographic changes, connectivity and genetic diversity need to be integrated for a successful assessment of population viability. Historically the Hazel grouse (Bonasa bonasia) in France was found in the north of the French Alps and also in a disjunct population in the nearby Jura Mountains. The species has recently undergone a range expansion in a north to south axis in the Alps. Local population size estimates and migration patterns during expansion have previously been studied. In this study, we performed genotyping at neutral (microsatellite) and adaptive (MHC) genetic markers in Hazel grouse. We compared diversity and differentiation (F_ST and D_EST) at three sampling localities along the expansion axis in the French Alps and Jura, as well as at two sampling localities in Sweden, where the population has had a long-term continuous and stable distribution. Strong serial founder effects were found between the French localities, resulting in stronger isolation further south, with a relatively high neutral differentiation (pair-wise F_ST = 0.117). However, the loss of adaptive diversity MHC was slight. No adaptive differentiation (MHC D_EST = ?0.015) was observed, thus, the French localities can be considered uniform units with regard to MHC diversity, a criterion to treat populations in these localities as a management unit.     

A side-reaction in the methylation of galacturonate derivatives with diazomethane-boron trifluoride etherate

Partial p-nitrobenzoylation of methyl (methyl 2-O-methyl-α-d-galactopyranosid)uronate (1) gave the 3-p-nitrobenzoate 2 in good yield. Treatment of 2 or methyl (methyl 2,3-di-O-benzoyl-α-d-galactopyranosid)uronate (11) with diazomethane-BF₃-etherate gave, in addition to the expected 4-methyl ethers, by-products resulting from lengthening of the carbon chain. The by-products were formulated as derivatives of methyl 4,7-anhydro-α-d-galacto-heptopyranosid-6-ulose dimethy acetal on the basis of p.m.r. and i.r. spectral data, by analysis of their mass-spectral fragmentation pattern, and by chemical transformations.     

Past and potential future population dynamics of three grouse species using ecological and whole genome coalescent modeling

Studying demographic history of species provides insight into how the past has shaped the current levels of overall biodiversity and genetic composition of species, but also how these species may react to future perturbations. Here we investigated the demographic history of the willow grouse (Lagopus lagopus), rock ptarmigan (Lagopus muta), and black grouse (Tetrao tetrix) through the Late Pleistocene using two complementary methods and whole genome data. Species distribution modeling (SDM) allowed us to estimate the total range size during the Last Interglacial (LIG) and Last Glacial Maximum (LGM) as well as to indicate potential population subdivisions. Pairwise Sequentially Markovian Coalescent (PSMC) allowed us to assess fluctuations in effective population size across the same period. Additionally, we used SDM to forecast the effect of future climate change on the three species over the next 50 years. We found that SDM predicts the largest range size for the cold‐adapted willow grouse and rock ptarmigan during the LGM. PSMC captured intraspecific population dynamics within the last glacial period, such that the willow grouse and rock ptarmigan showed multiple bottlenecks signifying recolonization events following the termination of the LGM. We also see signals of population subdivision during the last glacial period in the black grouse, but more data are needed to strengthen this hypothesis. All three species are likely to experience range contractions under future warming, with the strongest effect on willow grouse and rock ptarmigan due to their limited potential for northward expansion. Overall, by combining these two modeling approaches, we have provided a multifaceted examination of the biogeography of these species and how they have responded to climate change in the past. These results help us understand how cold‐adapted species may respond to future climate changes.     

Physiological responses of two wheat cultivars to soil drought

Young plants of the two wheat cultivars Katya and Prelom, differing in their reaction to drought in the field, were grown in soil in pots, and their water status was assessed as well as the intensity of gas exchange, chlorophyll fluorescence, and accumulation of compatible solutes and hydrogen peroxide after 7 days of dehydration. It was established that cv. Katya displayed markedly better tolerance to soil drying in comparison with cv. Prelom. This was partly due to the more effective control of water balance, activity of the photosynthetic apparatus, and metabolic activity of leaves under stress. Consequently, lower amounts of hydrogen peroxide were accumulated and a lower membrane injury index was determined.