Volume 71, Issue 12

L-Asparaginase is a potential therapeutic agent owing to its anti-tumor activity. We have previously characterized a thermostable L-asparaginase (TK1656F from Thermococcus kodakaraensis that exhibits highest ever reported enzymatic activity, no glutaminase activity and high stability. In this study we have compared the cytotoxicity and anti-proliferative activity of TK1656 and a commercially available L-asparaginase from Escherichia coli on cancerous cells. Despite of the thermophilic origin, the amount of TK1656 required to inhibit equivalent growth of HeLa cells at 37°C was three times less than that of the L-asparaginase from E. coli . It is worth mentioning that TK1656 showed much reduced cytotoxic effect on non-cancerous cells as compared to the E. coli counterpart. Furthermore, TK1656 was found to potentiate induction of apoptosis of cancerous cells. Overall, our findings suggest that TK1656 harbors a remarkable potential for the cancer chemotherapeutics.

Rehmanniae glutinosa , an important medical plant in China, has distinct regional characteristics. It has long suffered from consecutive monoculture obstacles, resulting in severe reduction of quality and yield. The microbial community is believed to play an important role in the monoculture process. However, there are no reports on how microbial compositions change in response to growth of R. glutinosa . In this study, quantitative real-time PCR and metagenomic high throughput sequencing methods were applied for the first time to elucidate the rhizosphere microbial community variation during growth and consecutive monoculture of R. glutinosa . The results indicated that with the first- and second-year cultivated process, the bacterial and fungal populations varied dramatically in rhizosphere soil, and the microbial balance was severely altered. Some probiotic bacteria (e.g., Actinomycetes), obviously decreased in abundance with consecutive monoculture and the abundances of some pathogenic fungi (e.g., Alternaria ) were obviously higher in the second-year cultivation than that in the first-year cultivation. In addition, we also found that microbial imbalance was tightly coupled with decreased soil pH and reductions in a series of soil enzyme activities. All these changes could be responsible for consecutive monoculture obstacles of R. glutinosa .

A group of Lamiaceae that has caused confusion over its generic boundaries are those species belonging to the complex surrounding the genera Satureja , Calamintha , Micromeria , Clinopodium and Acinos . In the current study, cross sections of root and stem of six Clinopodium taxa, previously treated as Acinos in Flora of Turkey, is studied for the first time and detailed descriptions and illustrations of root and stem are described and illustrated here. It is taxonomically interesting that the root and stems of these 6 taxa show similar histological characters except for a few differences, such as primary tissue structure in middle part of roots of C. troodi subsp. grandiflorum , cell numbers, types and density of trichome and prominent projecting at the corners in stem cross-section. The root center of studied Clinopodium taxa has a narrow pith consisting of primery xylem cells and the pith rays are 1–2-layered. Vascular bundles in all taxa are well-developed in the corners of the stems.

Aluminium (Al) toxicity is one of the major growth limiting factors that affects large agricultural areas resulting in reduced crop production in acid soils. The present study aims to investigate alleviating effects of salicylic acid (SA) on Al toxicity in barley ( Hordeum vulgare L.) roots. The roots were exposed to 20 µM AlCl 3 with or without SA (5 and 10 µM) for 72 h. In an alternative group, roots were pre-treated with 5 µM and 10 µM SA for 24 h, and then they were exposed to 20 µM AlCl 3 . To evaluate the ameliorating effects of SA on Al toxicity some cellular stress responses were investigated including root elongation, Al uptake, loss of plasma membrane integrity, mitotic abnormalities, superoxide dismutase activity, peroxidase activity, total protein content and DNA fragmentation. The obtained results suggested that both pre-treatment and co-treatment of 10 µM SA could alleviate Al-induced toxicity in barley roots in relation to inhibition of Al uptake and activation of the antioxidant enzyme system.

Here, the reversibility effects of salinity on Crithmum maritimum L. (Apiaceae), a perennial local oilseed halophyte that was recently suggested as a cash crop for biosaline agriculture, were checked by monitoring a number of parameters in pre-stressed plants and then, replaced in normal conditions. Plants previously grown for 15 days on basic medium were treated for one month by increasing NaCl concentrations (0, 100, 200 and 300 mM), or for three weeks by 300 mM NaCl and then put back again for a week on basic culture medium without salinity (R). Results revealed that C. maritimum was able to tolerate 100 mM NaCl concentration in the culture medium following an efficient N assimilation in roots and osmotic adjustment in leaves and roots. However, from 200 mM NaCl treatment, a significant and progressive reduction in plant growth was observed, mainly due to salt ions-induced limitations of mineral nutrient acquisition and N-assimilating enzymes (NR and GS) in both organs rather than osmotic effects. Interestingly, a one week of 300 mM NaCl elimination allowed C. maritimum plants to achieve their normal growth status through a partial dilution of Na + and Cl − effects on nutrients, osmotically compatible solutes, and activities of N-assimilating enzymes to levels similar to that obtained under 100 mM NaCl. Taken together, it was concluded that a temporary exposition of C. maritimum to salt stress is not necessary followed by significant depreciation in product yield and quality, which highlighted the reversibility effects of salinity on this plant species.

To analyse the reproductive activity of the central-European clausiliid Cochlodina orthostoma we sampled monthly 30 adults from three sites comprising old stone walls of two abandoned castles and isolated limestone rocks. Out of the 395 dissected snails, 25.1% retained eggs. The number of eggs in the uterus ranged from 2 to 12. The highest percentages of gravid individuals were recorded in June–July, but reproductive intensity varied among populations. Almost half of the recorded eggs contained a shelled embryo. The largest embryonic shell featured approximately 1.3 whorls. The reproductive mode of the species was also studied in laboratory culture. Egg-laying was observed between May and November, the number of eggs laid on a single occasion ranged from 1 to 8, and the number of eggs produced per individual varied between 6 and 21 during the observation period. We found that eggs were laid in various developmental stages, accordingly, there were differences in egg sizes and the external incubation period varied between 6 and 15 days. Based on our results C. orthostoma should be regarded as brooding species with a short and flexible period of egg retention.

Meteor crater ponds are extremely rare types of water body and consequently their environment, along with inhabiting fauna, are poorly recognised. We investigated the zooplankton community structure of three meteorite ponds. Their hydroperiod is usually the longest during the spring season, therefore the study-time covered the months between April and June. Within the craters we found 140 zooplankton species, which contributed to 20% of rotifer, 19% of cladoceran, 15% of copepod and 3% of ostracod Polish species. Our results showed a high diversity of zooplankton inhabiting these temporary ecosystems, even though we examined craters before the optimum of macrophyte development, which supports increase of invertebrate species richness. Only 43% of the species were common for all three ponds, although the meteorite craters were located very close to each other, possess the same catchment area and all were fishless. The high specificity of each pond was underlined by a high number of distinctive species (containing almost 30% of the total taxonomic structure). Zooplankton mainly consisted of eurytopic and common species, with representatives of families Brachionidae, Daphnidae and Cyclopidae having the highest frequency. However, over 10% of all species (e.g., Lecane elsa and Tretocephala ambigua ) were determined as rare in Poland. Therefore these meteorite ponds are of a high conservation value despite the close proximity of a large urban agglomeration.

Astacus leptodactylus is a widespread European crayfish species with both native and invasive populations. However, in spite of its wide distribution, studies regarding its activity seem to be lacking. Thus, our goal was to study its preference towards shelters built from natural and artificial materials and follow its activities throughout the day in order to understand its diel activity patterns. We analyzed the video recordings of diel activities for 20 individuals to find out more about this species routine in a captive environment. Every specimen spent 22 hours in an arena with 4 different kinds of shelters provided (stone, wood, PVC pipe, vegetation). We investigated time spent in every shelter and different activity patterns throughout the analysis period. A preference for stone and wooden shelters was clearly expressed by all the individuals, independent of sex and size. Most of the activity was concentrated in close proximity to the provided shelters. Individuals exhibited both daytime and nighttime activity, with the latter being more intense, although, specimens spent almost 85% of the entire time inside shelters. Crayfish used all available shelters during our trials, proving a wide flexibility of the species towards shelter type, but the frequency of visits and time spent inside certain type of shelter varied significantly. Our study brings novel information regarding narrow-clawed crayfish shelter preference and activity in the proximity of the shelters, highlighting the importance of natural refuges in its daily routine.

The marbled craynsn ( Procambarus fallax f. virginalis ) has become one of the potentially most dangerous nonindigenous crayfish species spreading in European countries and elsewhere. This taxon reproduces parthenogenetically and recently has been verified as a vector of the crayfish plague pathogen. Here, we report on two established populations of marbled crayfish in the Czech Republic. The marbled crayfish was observed during autumn 2015 in an urban pond connected by sewer piping with the Rokytka brook near its mouth to the Vltava River in Prague. Subsequently, three adult females, two of them having well-developed glair glands and oocytes, were captured in this pond during spring 2016, suggesting successful overwintering of the local population. Furthermore, four adult females were captured in an artificial pond at the Radovesická lignite spoil heap in the vicinity to the industrial conurbation of Bílina in summer 2016; one of them carried eggs. We tested these for the presence of the crayfish plague pathogen Aphanomyces astaci , with negative results. The introduction pathway for both populations is most likely a release from private aquaria, as these sites are popular for recreation activities. Our findings substantiate previous predictions that conurbations are likely to be the primary areas for marbled crayfish introductions.

In this study we used molecular markers to characterize various populations of the Ephedrus persicae species group originating from different aphid hosts and different habitat types. Twelve different haplotypes were identified in 15 E. persicae specimens, and thus there were no shared haplotypes between specimens from different aphid hosts. All haplotypes were clustered in two distinct phylogenetic clades (“persicae 1” and “persicae 2”), the average genetic distance between these two clades being 3.1%. Ephedrus persicae specimens from the “persicae 1” clade parasitize leaf-curling aphids from Prunus and Malus orchards. Furthermore, there was significant differentiation of the “persicae 2” clade into two distinct evolutionary groups, with a genetic distance of 2.5% between them. On the basis of the genetically isolated position of Ephedrus specimens associated with Brachyunguis tamaricis on Tamarix gallica (more than 5.7% genetic distance), we describe Ephedrus tamaricis sp. n. as an additional member of the E. percicae species group. Key for identification of parasitoids belonging to the E. persicae species group is provided.

Stable isotope analysis (SIA) of carbon and nitrogen sheds light on the origin of the food resources exploited by the fish and provides basic information on the trophic relationships among taxa. In this study, SIA of C and N was used to investigate the trophic behavior of fish species in a small Mediterranean reservoir, Lake Sos Canales (SC) in Sardinia, Italy, during an annual hydrological cycle. Fish were caught approximately every two months, and baseline isotopic C and N levels in the pelagic and littoral area were analyzed to establish the origin of fish food sources, considering suspended particulate matter, planktonic crustaceans and littoral macroinvertebrates. To assess the relative contribution of the two different sources using SIA, a Dynamic Baseline Mixing Model (DBMM) was applied and the results were compared with the fish gut contents. Our aim was to chart the seasonal trophic behavior of the fish species inhabiting an anthropogenic aquatic environment under considerable stress due to water level fluctuations. Isotopic results showed a seasonal trend with 13 C levels depleted more in autumn-winter and less in spring-summer, while an inverse trend was recorded for 15 N, both in the isotopic baseline values and in the fish. Isotopic results and gut content analysis highlighted a year-round strict dependence on littoral food sources only for the brown trout, whereas the mosquitofish changed their trophic behavior seasonally, shifting from littoral (high water level period) to pelagic (low water level period) food sources, mirroring the hydrological conditions of Lake SC.

Fat-inducing transcript 2 (FIT2) plays an important role in the formation of intramuscular lipid droplets in skeletal muscle. However, its role in porcine intramuscular preadipocyte differentiation remains unclear. In the present study, a 789-bp fragment covering the complete coding region of porcine FIT2 ( p FIT2 ) was obtained. Real-time quantitative PCR analysis indicated that p FIT2 mRNA was highly expressed in fat tissue. Overexpression of p FIT2 in porcine intramuscular preadipocytes led to an increase in lipid accumulation, which was detected by triglyceride content analysis. Overexpression of p FIT2 also significantly increased the protein expressions of peroxisome proliferator-activated receptor γ ( PPARγ ) and CCAAT-enhancer binding protein-α (C/EBP α ), but decreased the protein expression of β -catenin. We also found that the Wnt/ β -catenin signaling specific activator LiCl attenuated the p FIT2-induced upregulation of PPAR γ and downregulation of β -catenin. These findings implied that FIT2 promotes porcine intramuscular preadipocyte differentiation by repressing Wnt/ β -catenin signaling.