Use of the luciferin-luciferase assay of ATP for measuring the bacterial growth: Application to Escherichia coli

The relative constancy of ATP content per unit of dry biomass in different microorganisms enables to use the specific, sensitive and quick luciferin-luciferase method for ATP assay for indirect quantitation of microbial biomass by measuring the ATP content in biomass samples.The aim of this work was to investigate the feasibility of using the ATP concentration for the monitoring of the growth of Escherichia coli K 12 W 3350 in different cultivation conditions. Statistically significant high correlation coefficients (r > 0.9) between the ATP content (ATP/ml) and the other growth characteristics examined showed that the ATP content of the culture is as suitable characteristic as the optical density of the culture, total cell number per ml or total cell volume per ml for the monitoring of the growth of E.coliin batch culture in mineral medium with glucose at different growth temperatures (27–42 °C) as well as in fed-batch culture.     

Localization of metabolites which are regulators of extracellular protease synthesis in Pseudomonas fluorescens bacteria

The effect of over forty low molecular weight substrates on the growth and synthesis of exocellular neutral proteases was studied in Pseudomonas fluorescens. Neutral exoproteases were found to be regulated enzymes. Glucose did not repress the synthesis of exocellular proteases; the regulation of their synthesis by amino acids involved the mechanism of induction. The data suggest that the primary intracellular inductors of the synthesis of exoproteases are formed for different groups of amino acids at different levels of their utilization by the cells, viz. at the level of transport and at the level of the first steps in the degradation of their carbon backbones. The paper discusses possible molecular mechanisms for integrating the signal of the primary intracellular inductors, which directly regulate the activity of the operon(s) of neutral exocellular proteases.     

Dilation of human atria: Increased diffusion restrictions for ADP,overexpression of hexokinase 2 and its coupling to oxidative phosphorylation in cardiomyocytes

Cardiac energy metabolism with emphasis on mitochondria was addressed in atrial tissue from patients with overload-induced atrial dilation. Structural remodeling of dilated (D) atria manifested as intracellular accumulation of fibrillar aggregates, lipofuscin, signs of myolysis and autophagy. Despite impaired complex I dependent respiration and increased diffusion restriction for ADP, no changes regarding adenylate and creatine kinase occurred. We observed 7-fold overexpression of HK2 gene in D atria with concomitant 2-fold greater activation of mitochondrial oxygen consumption by glucose, which might represent an adaption to increased energy requirements and impaired mitochondrial function by effectively joining glycolysis and oxidative phosphorylation.     

Wild plants eaten in childhood: a retrospective of Estonia in the 1970s–1990s

In this ethnobotanical study, the authors provide the first quantitative analysis of the use of wild edible plants in Estonia, describing the domains and assessing the food importance of different species. The information was collected using free‐listing written questionnaires and concerned plants used by the respondents in their childhood. As part of a major study, this article covers the responses of professionals with some botanical education at vocational or university level, to ensure the greatest possible reliability without using voucher specimens. Fifty‐eight respondents provided information on the use of 137 plant taxa, corresponding to approximately 6% of the native and naturalized vascular plants of Estonia. According to use frequency, the most typical wild food plant of Estonia is a fruit, eaten raw as a snack. The results clearly signal that the majority of famine and food shortage plants had already been forgotten by the end of the 20^th century, but new plants have been introduced as green vegetables for making salads. Despite changes in the nomenclature of the plants, the use of wild food plants in Estonia was still thriving at the turn of the 20^th century, covering many domains already forgotten in urbanized modern Europe. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 172 , 239–253.     

Variation in eggshell traits between geographically distant populations of pied flycatchers Ficedula hypoleuca

The expression and impact of maternal effects may vary greatly between populations and environments. However, little is known about large‐scale geographical patterns of variation in maternal deposition to eggs. In birds, as in other oviparous animals, the outermost maternal component of an egg is the shell, which protects the embryo, provides essential mineral resources and allows its interaction with the environment in the form of gas exchange. In this study, we explored variation of eggshell traits (mass, thickness, pore density and pigmentation) across 15 pied flycatcher populations at a large geographic scale. We found significant between‐population variation in all eggshell traits, except in pore density, suggesting spatial variation in their adaptive benefits or in the females’ physiological limitations during egg laying. Between‐ population variation in shell structure was not due to geographic location (latitude and longitude) or habitat type. However, eggshells were thicker in populations that experienced higher ambient temperature during egg laying. This could be a result of maternal resource allocation to the shell being constrained under low temperatures or of an adaptation to reduce egg water loss under high temperatures. We also found that eggshell colour intensity was positively associated with biliverdin pigment concentration, shell thickness and pore density. To conclude, our findings reveal large‐ scale between‐population variation of eggshell traits, although we found little environmental dependency in their expression. Our findings call for further studies that explore other environmental factors (e.g. calcium availability and pollution levels) and social factors like sexual selection intensity that may account for differences in shell structure between populations.     

Increased Blood Levels of Growth Factors,Proinflammatory Cytokines,and Th17 Cytokines in Patients with Newly Diagnosed Type 1 Diabetes

The production of several cytokines could be dysregulated in type 1 diabetes (T1D). In particular, the activation of T helper (Th) type 1 (Th₁) cells has been proposed to underlie the autoimmune pathogenesis of the disease, although roles for inflammatory processes and the Th₁₇ pathway have also been shown. Nevertheless, despite evidence for the role of cytokines before and at the onset of T1D, the corresponding findings are inconsistent across studies. Moreover, conflicting data exist regarding the blood cytokine levels in T1D patients. The current study was performed to investigate genetic and autoantibody markers in association with the peripheral blood cytokine profiles by xMap multiplex technology in newly diagnosed young T1D patients and age-matched healthy controls. The onset of young-age T1D was characterized by the upregulation of growth factors, including granulocyte macrophage-colony stimulating factor (GM-CSF) and interleukin (IL)-7, the proinflammatory cytokine IL-1β (but not IL-6 or tumor necrosis factor [TNF]-α), Th₁₇ cytokines, and the regulatory cytokines IL-10 and IL-27. Ketoacidosis and autoantibodies (anti-IA-2 and -ZnT8), but not human leukocyte antigen (HLA) genotype, influenced the blood cytokine levels. These findings broaden the current understanding of the dysregulation of systemic levels of several key cytokines at the young-age onset of T1D and provide a further basis for the development of novel immunoregulatory treatments in this disease.     

Cell transduction pathways of transportans

Attempts to unravel the cell translocation mechanism of a growing number of cell-penetrating peptides (CPP) have revealed molecular determinants essential for internalization ability. The peptide sequence and the charge have been proposed to be the major factors in determining the membrane interaction mode and subsequent internalization pathway. Recent research in this field has shifted to search and design of novel CPPs with predefined vectorial properties and elucidation of the mechanism of cell entry of CPPs with high cargo delivery efficiency. Here we present a map of interaction modes with cell surface and intracellular traffic of transportan and its analogue TP10 complexed with fluorescently labeled avidin or streptavidin-gold conjugates. The protein cargo complexed with either peptide is transduced into HeLa and Bowes cells mostly in the endocytic vesicles with heterogeneous morphology and size as demonstrated by transmission electron microscopy (TEM) and confocal laser scanning fluorescence microscopy. Most of the induced vesicles are large, with 0.5-2 mum diameter, probably macropinosomes, but the complexes are present also in smaller vesicles, suggesting involvement of different pathways. Later the majority of complexes are translocated from the cell periphery into vesicles of perinuclear region and partly to lysosomes. A fraction of transportan-streptavidin complexes is present also freely in cytoplasm, both in the close vicinity of plasma membrane and more centrally, suggesting the escape from endosomal vesicles, since vesicles with discontinuous membrane were also detected by TEM. The cell-translocation process of transportan-protein complexes is temperature dependent and strongly inhibited at 8-10 degrees C and blocked at 4 degrees C when only interaction with the plasma membrane takes place.     

Chick development in free-living great tits Parus major in relation to calcium availability and egg composition

Evidence from a number of avian studies suggests that limitation of exogenous calcium (Ca) may reduce egg quality and retard nestling growth. However, it is poorly understood whether reduction in chick growth in Ca-poor areas is due to insufficient intake of dietary Ca or caused by maternal Ca limitation mediated through subtle changes in composition of eggs. In this study, we provide new evidence that Ca availability during egg formation may indeed affect egg composition and influence chick development of the great tit Parus major at early developmental stages. Ca-supplemented birds breeding in base-poor pine forests produced eggs with elevated yolk Ca concentration compared with controls, while no such effect of supplementation was detected in case of eggshell thickness. Nestling tarsus length in the first half of the nestling period was positively influenced by both yolk dry mass and yolk Ca concentration. The effect of supplementary Ca did not persist throughout the nestling period; initial effects of egg components disappeared as nestlings aged. We conclude that apparently normal eggs may harbor poor nutrient and mineral conditions for chick growth. Such subtle changes in composition of eggs can depress chick growth, especially in harsh years.