Enhanced production of erythritol by Yarrowia lipolytica on glycerol in repeated batch cultures

Erythritol is an important natural sweetener, industrially produced only by fermentation on glucose media. Glycerol is an important renewable feedstock as it is the major by-product of the biodiesel production process; here we present an alternative way to convert this low-cost substrate into value-added products, such as erythritol. Repeated batch cultures (RBC) were performed to improve the productivity of erythritol from pure and crude glycerol. An acetate negative mutant of Yarrowia lipolytica Wratislavia K1 was found to be applicable for the production of high amounts of erythritol in RBC. When 20 % of fresh replaced medium was added, the strain Wratislavia K1 was able to produce 220 g l ^?1 erythritol, which corresponded to a 0.43 g g^?1 yield and a productivity of 0.54 g l^?1 h^?1. Additionally, the activity of the culture remained stable for more than 1,000 h, i.e., 11 cycles of the repeated batch bioreactors.     

Yeast ABC proteins involved in multidrug resistance

Pleiotropic drug resistance is a complex phenomenon that involves many proteins that together create a network. One of the common mechanisms of multidrug resistance in eukaryotic cells is the active efflux of a broad range of xenobiotics through ATP-binding cassette (ABC) transporters. Saccharomyces cerevisiae is often used as a model to study such activity because of the functional and structural similarities of its ABC transporters to mammalian ones. Numerous ABC transporters are found in humans and some are associated with the resistance of tumors to chemotherapeutics. Efflux pump modulators that change the activity of ABC proteins are the most promising candidate drugs to overcome such resistance. These modulators can be chemically synthesized or isolated from natural sources (e.g., plant alkaloids) and might also be used in the treatment of fungal infections. There are several generations of synthetic modulators that differ in specificity, toxicity and effectiveness, and are often used for other clinical effects.     

Source regions of ragweed pollen arriving in south-western Poland and the influence of meteorological data on the HYSPLIT model results

We have investigated the relationship between the inflow of air masses and the ragweed pollen concentration in SW Poland (Wroc?aw) for a 10-year period of 2005–2014. The HYSPLIT trajectory model was used to verify whether episodes of high concentrations can be related to regions outside of the main known ragweed centres in Europe, like Pannonian Plain, northern Italy and Ukraine. Furthermore, we used two different meteorological data sets (the global GDAS data set and from the WRF mesoscale model; the meteorological parameters were: U and V wind components, temperature and relative humidity) into HYSPLIT to evaluate the influence of meteorological input on calculated trajectories for high concentration ragweed episodes. The results show that the episodes of high pollen concentration (above 20 pm^?3) represent a great part of total recorded ragweed pollen in Wroc?aw, but occur rarely and not in all years. High pollen episodes are connected with air masses coming from south and south-west Europe, which confirms the existence of expected ragweed centres but showed that other centres near Wroc?aw are not present. The HYSPLIT simulations with two different meteorological inputs indicated that footprint studies on ragweed benefit from a higher resolution meteorological data sets.     

Decolorization of beet molasses vinasse by Bacillus megaterium ATCC 14581

Beet molasses vinasse is formed in large quantities as a waste product of the distillery industry, where the molasses derived from sugar beet is used as a raw material. This vinasse has a dark color, low pH, and chelating properties. Many microorganisms have the ability to decolorize and biodegrade beet molasses vinasse. In this work, different cultivation parameters (the type of the bacterial culture; static or agitated) and medium components ((NH₄)₂SO₄, KH₂PO₄, yeast extract, glucose, and peptone, and the vinasse concentration) were evaluated utilizing Plackett-Burman design to identify the important factors influencing the vinasse decolorization by Bacillus megaterium ATCC 14581. The significant variables were selected as follows: (NH₄)₂SO₄, KH₂PO₄, glucose, and the concentration of vinasse. These four factors should be chosen as being promising for further optimization studies. The maximum color removal was 38%.     

The genetic characterization of an isolated remnant population of an endangered rodent (<Emphasis Type="Italic">Cricetus cricetus</Emphasis> L.) using comparative data: implications for conservation

Estimates of genetic diversity and phylogenetic affiliation represent an important resource for biodiversity assessment and a valuable guide to conservation and management. We have found a new population (Jawor—JW) of the common hamster Cricetus cricetus in western Poland that is remote from the nearest populations by 235–300 km. With the objective of genetically characterizing of this population, we compared it with other populations from Poland and Germany by taking into account sequences of four mitochondrial DNA genes and variation at 10 microsatellite loci. The JW population exhibited low levels of genetic diversity and allelic and haplotype richness, which likely reflects its extreme isolation. This factor, coupled with inbreeding and genetic drift, are major threats to JW. A neighbor-joining tree based on mtDNA haplotypes shows that JW clusters among samples representing the Central subgroup that is known from central Germany but that has not yet been identified in Poland. Findings presented here improve our understanding of the spread and diversification of the common hamster. We offer the following hypotheses to explain the observed pattern of mtDNA haplotype distribution: JW could be a byproduct of postglacial migrations or back-migrations from eastern refugia to the western part of Europe, or/and be a result of population and habitat fragmentation. We recommend translocation of individuals as an effective management strategy, both at the level of Central phylogeographic group and at the species level, to overcome the negative consequences of inbreeding and geographical isolation of the JW population.     

Vertebrates from the Pontian of the Shkodova Gora locality (Northwestern Black Sea Region,Upper Miocene)

Remains of fishes, turtles, birds, and mammals are described from the Upper Miocene (MN13) Shkodova Gora locality (Ukraine, Odessa Region), the only representative locality of Pontian large vertebrates in the northwestern Black Sea Region. Asiatic fish and avian taxa are recorded for the first time in the Upper Miocene of Europe. The Shkodova Gora ichthyofauna includes eight freshwater fish species (belonging to Acipenseridae, Cyprinidae, Siluridae, and Percidae). Taxa that have previously been recorded only in Western Siberia (Abramis bliccoides, Perca lepidopoma), eastern Kazakhstan, and the Altai Mountain (Rutilus tungurukensis) are revealed. Acipenser gueldenstaedtii is recorded for the first time in the Upper Miocene of Eastern Europe. The occurrence of the genus Ctenopharyngodon, a member of the Chinese plain faunal assemblage is of great interest. The Shkodova Gora avifauna (seven taxa) is mostly composed of waterfowl, including Phalacrocorax mongoliensis, which has previously been known only from the Lower Pliocene of Mongolia. The finding of Proanser major is the youngest record of this species in the fossil record. Mammals of the Shkodova Gora association include a hare resembling Trischizolagus dumitrescuae, Palaeoryx cf. pallasi, and Hipparion cf. moldavicum, which have not been mentioned among Pontian taxa of the northern Black Sea Region. Pontian paleolandscapes in the area of the Shkodova Gora locality are reconstructed.     

Did the historical range of the European bison (<Emphasis Type="Italic">Bison bonasus</Emphasis> L.) extend further south?—a new finding from the Yenikapı Metro and Marmaray excavation,Turkey

The origin of the European bison (Bison bonasus, Linnaeus, 1758) has been widely discussed and investigated in recent years. The species had a wide historic geographic distribution throughout the European continent during the middle and late Holocene, ranging from France in the west to the Caucasus in the east. However, archaeological evidence is needed to resolve the southern extent of the European bison distribution. We discovered one bison skull fragment during archaeological excavations in 2008 in the area of Yenikap? Metro and Marmaray (Turkey). Radiocarbon dating indicated the skull was deposited during the Byzantine period (seventh to eighth century AD). Mitochondrial genome analyses provided clear evidence that the skull was from a European bison. This is the first unambiguous evidence of the presence of this species in southeastern Europe during Byzantine times, which validates the historical written records of a potentially wider range of the European bison in historical times.     

The Coordination Abilities of New Cyclic Analogs of Somatostatin

Two new somatostatin analogs with a characteristic part of the sequence -c(Cys-Phe-Trp-Lys-Thr-Cys)- and with two histidine and two aspartic acid moieties in their structures were synthesized and analyzed in terms of their coordination abilities with copper (II) ions. Both peptides bind Cu(II) effectively. Ligands form 4N complexes with \(\left\{ {{\text{N}}_{\text{Im}} ,{ 3} {\text{N}}_{\text{amide}}^{ - } } \right\}\) binding mode in a basic range of pH. But in spite of very similar sequences of the two peptides a significant difference in the effectiveness of the binding of copper (II) ions was observed.     

The effects of the DNA methyltranfserases inhibitor 5‐Azacitidine on ageing,oxidative stress and DNA methylation of adipose derived stem cells

Human adipose tissue is a great source of adult mesenchymal stem cells (MSCs) which are recognized from their ability to self‐renew and differentiation into multiple lineages. MSCs have promised a vast therapeutic potential in treatment many diseases including tissue injury and immune disorders. However, their regenerative potential profoundly depends on patients’ age. Age‐related deterioration of MSC is associated with cellular senescence mainly caused by increased DNA methylation status, accumulation of oxidative stress factors and mitochondria dysfunction. We found that DNA methyltransferase (DNMT) inhibitor i.e. 5‐Azacytidine (5‐AZA) reversed the aged phenotype of MSCs. Proliferation rate of cells cultured with 5‐AZA was increased while the accumulation of oxidative stress factors and DNA methylation status were decreased. Simultaneously the mRNA levels of TET proteins involved in demethylation process were elevated in those cells. Moreover, cells treated with 5‐AZA displayed reduced reactive oxygen species (ROS) accumulation, ameliorated superoxide dismutase activity and increased BCL‐2/BAX ratio in comparison to control group. Our results indicates that, treating MSCs with 5‐AZA can be justified therapeutic intervention, that can slow‐down and even reverse aged‐ related degenerative changes in those cells.