The Role of Mitochondrial DNA ORIB Polymorphism in Metabolic Syndrome

The development of the metabolic syndrome (MS) involves many genes. Certain evidence exists in the literature on the association of polymorphism in the mitochondrial DNA (mtDNA) oriB site, also known as the polycytosine pathway, with the development of insulin resistance, type 2 diabetes mellitus (T2DM) and other metabolic disorders in various ethnic populations. It is suggested that certain polymorphisms at this site are associated with mtDNA copy number in the cell. In this study, using capillary sequencing, we have identified various allelic variants of the mtDNA oriB site in patients with MS (n = 106) and conditionally healthy donors (n = 71). The mtDNA copy number in blood leukocytes was determined by the droplet digital polymerase chain reaction (ddPCR). It has been shown that the variant of the continuous polycytosine tract is significantly more frequent in MS patients with T2DM (p < 0.01). In general, the mtDNA copy number of blood leukocytes was lower in MS patients than in controls. We did not find any correlations between the oriB site variability and the mtDNA copy number.     

Adaptive changes in pigment complex of <Emphasis Type="Italic">Pinus sylvestris</Emphasis> needles upon cold acclimation

We studied seasonal changes in the content and ratio between photosynthetic pigments in one-yearold needles of Scotch pine (Pinus sylvestris L.) growing in Central Yakutia. Maximum accumulation of chlorophylls in developed young needles occurred in July when light and temperature conditions were favorable. In this period, the needles were notable for a relatively high level of β-carotene and neoxanthin and a reduced content of lutein and the pigments of violaxanthin cycle (VXC). In the course of autumn hardening, the content of chlorophylls decreased two times. Total content of carotenoids remained the same, but pigment composition considerably changed when plants progressed from a vegetating to frost-resistant state. We revealed time and temperature ranges of variation for individual carotenoids. In the beginning of hardening at reduced and low abovezero temperatures, the content of β-carotene in the needles decreased, the pigment-protein complexes (PPC) became enriched in lutein, the pigment pool of VXC gradually increased, and the content of neoxanthin transiently rose. When average daily air temperature further decreased to near- zero values, the content of zeaxanthin sharply rose. In winter, high levels of lutein and zeaxanthin were maintained. Main changes in pigment complex of the needles of P. sylvestris were completed before the coming of steady below-zero temperatures. The obtained data suggested that, upon seasonal decrease in temperature in early stages of hardening, a decrease in the level of chlorophyll promotes a reduction in the quantity of absorbed radiant energy. Apparently, this is accompanied by activation of the role of lutein and neoxanthin that perform specific photoprotective functions in antenna PPC associated with a gradual decrease in plants’ ability to quench singlet energy of excited chlorophyll. Accumulation of zeaxanthin as a result of inhibition of back reaction of epoxidation at near-zero temperatures creates necessary prerequisites for turning on the mechanisms of steady dissipation of absorbed light energy, which do not depend on transmembrane proton gradient of thylakoids. At the same time, zeaxanthin can perform antioxidant functions both in PPC and in the lipid phase of thylakoid membranes. The obtained data point to an adaptive nature of the observed reactions and a specific role of individual pigments in structural and functional reorganization of photosynthetic machinery in the course of development of frost-resistance in the needles.     

Developing criteria for evaluation of geroprotectors as a key stage toward translation to the clinic

In the coming decades, a massive shift in the aging segment of the population will have major social and economic consequences around the world. One way to offset this increase is to expedite the development of geroprotectors, substances that slow aging, repair age‐associated damage and extend healthy lifespan, or healthspan. While over 200 geroprotectors are now reported in model organisms and some are in human use for specific disease indications, the path toward determining whether they affect aging in humans remains obscure. Translation to the clinic is hampered by multiple issues including absence of a common set of criteria to define, select, and classify these substances, given the complexity of the aging process and their enormous diversity in mechanism of action. Translational research efforts would benefit from the formation of a scientific consensus on the following: the definition of ‘geroprotector’, the selection criteria for geroprotectors, a comprehensive classification system, and an analytical model. Here, we review current approaches to selection and put forth our own suggested selection criteria. Standardizing selection of geroprotectors will streamline discovery and analysis of new candidates, saving time and cost involved in translation to clinic.     

The Evolution of Human Probiotics: Challenges and Prospects

Probiotics and Antimicrobial Proteins - In recent years, the intestinal microbiota has been found to greatly influence a number of biological processes important for human health and longevity....     

The first dinosaur egg from the Lower Cretaceous of Western Siberia,Russia

The Lower Cretaceous Ilek Formation in Western Siberia (Russia) has yielded various vertebrate fossils, including skeletal remains of dinosaurs. Here we report on a fragmentary theropod egg from the vertebrate locality Shestakovo 3 of the Ilek Formation in Kemerovo Province. We assign the specimen to the oogenus Prismatoolithus (oofamily Prismatoolithidae) as Prismatoolithus ilekensis oosp. nov., on the basis of the following unique combination of characters: ovoid-shaped egg; thin eggshell 300–330 μm thick; angustiprismatic morphotype; eggshell with three different layers; gradual transition between mammillary layer and prismatic layer; abrupt contact between prismatic layer and external layer; mammillary layer to prismatic layer to external layer thickness ratio is 1:3:0.6; prismatic layer with ill-defined squamatic texture; angusticanaliculate pore system; and smooth outer surface. Like other Early Creataceous Prismatoolithus, the egg of Prismatoolithus ilekensis oosp. nov. was laid by a small bodied theropod dinosaur (troodontid or primitive bird) and this taxonomic attribution is supported by results of our phylogenetic analysis. Prismatoolithus ilekensis oosp. nov. is the first Early Cretaceous ootaxon from Russia.

urn:lsid:zoobank.org:act:734EAD40-86C3-488B-A61E-B5FF7378BC0E     

<Emphasis Type="Italic">Thermincola ferriacetica</Emphasis> sp. nov<Emphasis Type="Italic">.,</Emphasis> a new anaerobic,thermophilic, facultatively chemolithoautotrophic bacterium capable of dissimilatory Fe(III) reduction

A moderately thermophilic, sporeforming bacterium able to reduce amorphous Fe(III)-hydroxide was isolated from ferric deposits of a terrestrial hydrothermal spring, Kunashir Island (Kurils), and designated as strain Z-0001. Cells of strain Z-0001 were straight, Gram-positive rods, slowly motile. Strain Z-0001 was found to be an obligate anaerobe. It grew in the temperature range from 45 to 70°C with an optimum at 57–60°C, in a pH range from 5.9 to 8.0 with an optimum at 7.0–7.2, and in NaCl concentration range 0–3.5% with an optimum at 0%. Molecular hydrogen, acetate, peptone, yeast and beef extracts, glycogen, glycolate, pyruvate, betaine, choline, N-acetyl-d-glucosamine and casamino acids were used as energy substrates for growth in presence of Fe(III) as an electron acceptor. Sugars did not support growth. Magnetite, Mn(IV) and anthraquinone-2,6-disulfonate served as the alternative electron acceptors, supporting the growth of isolate Z-0001 with acetate as electron donor. Formation of magnetite was observed when amorphous Fe(III) hydroxide was used as electron acceptor. Yeast extract, if added, stimulated growth, but was not required. Isolate Z-0001 was able to grow chemolithoautotrophicaly with molecular hydrogen as the only energy substrate, Fe(III) as electron acceptor and CO₂ as the carbon source. Isolate Z-0001 was able to grow with 100% CO as the sole energy source, producing H₂ and CO₂, requiring the presence of 0.2 g l⁻¹ of acetate as the carbon source. The G+C content of strain Z-0001^T DNA G+C was 47.8 mol%. Based on 16S rRNA sequence analyses strain Z-0001 fell into the cluster of family Peptococcaceae, within the low G+C content Gram-Positive bacteria, clustering with Thermincola carboxydophila (98% similarity). DNA–DNA hybridization with T. carboxydophila was 27%. On the basis of physiological and phylogenetic data it is proposed that strain Z-0001^T (=DSMZ 14005, VKM B-2307) should be placed in the genus Thermincola as a new species Thermincola ferriacetica sp. nov. The GenBank accession number for the sequence reported in the paper is AY 631277.     

Complete Genome Sequence of Desulfurococcus fermentans,a Hyperthermophilic Cellulolytic Crenarchaeon Isolated from a Freshwater Hot Spring in Kamchatka,Russia

Desulfurococcus fermentans is the first known cellulolytic archaeon. This hyperthermophilic and strictly anaerobic crenarchaeon produces hydrogen from fermentation of various carbohydrates and peptides without inhibition by accumulating hydrogen. The complete genome sequence reported here suggested that D. fermentans employs membrane-bound hydrogenases and novel glycohydrolases for hydrogen production from cellulose.