Growth characteristics of haploid and diploid Hansenula polymorpha yeasts on methanol in continuous culture

The rate of growth and the yield of biomass of a Hunsenula polymorpha homozygous diploid strain ML-3 X ML-3 were nearly identical with those of the parent haploid culture ML-3. The two cultures were eliminated from the fermenter at D = 0.20 to 0.21 h-1. In contrast, a heterozygous diploid strain ML-3 X VKM 1397 could grow at D = 0.23 to 0.25 h-1 and its biomass yield reached 38% while the yields of the haploid and homozygous diploid strains were 35 to 36%. The pH of the medium had the same effect on the three cultures: a change in the pH from 4.0 to 3.5 and then to 3.0 did not influence the yield of biomass; a further pH drop to 2.5 made the cells be eliminated from the fermenter.     

Comparative Characteristics of the Chemical Composition of Some Brown Algae from the White and Yellow Seas

Russian Journal of Bioorganic Chemistry - Brown algae represent a valuable source of various biologically active compounds. Their accumulation is influenced by many environmental factors. The...     

European checkerspots (Melitaeini: Lepidoptera,Nymphalidae) are not aposematic – the point of view of great tits (Parus major)

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Investigation of erythrocyte shape, plasma membrane fluidity and conformation of haemoglobin haemoporphyrin under the influence of long-term space flight

The investigation of long-term space flight (SF) effect on the blood cells function is of great importance for modern space biology and medicine. We established that the number of discocytes decreased in the period of early rehabilitation after long-term SF. After SF plasma membrane fluidity and phospholipid content decreased and cholesterol content increased. After SF the amount of haemoglobin decreased and the parameters characterizing haemoglobin haemoporyphyrin (HH) conformation changed. We suppose that erythrocyte shape, membrane fluidity and HH conformation are among factors affecting oxygen transfer during and after space flight.     

Effect of tumor necrosis factor DNA on immune response to DNA immunization against herpes simplex virus

A study was made of the adjuvant effect of the mouse tumor necrosis factor alpha (mTNF alpha) on DNA immunization against the herpes simplex virus type 1 (HSV1). The HSV1 gD gene (pDNAgD) served as an immunogen; mTNF alpha or its gene cloned in an eukaryotic expression vector (pDNAmTNF) were used to modulate the immune response. Double immunization with pDNAgD led to a sixfold increase in the in vitro T-cell response, a high (1:2000) titer of anti-HSV1 antibodies (including virus-neutralizing antibodies), an increase in IgG2a/IgG1 (suggesting a shift of the immune response to the Th1 type), and no change in CD4/CD8 T-cell ratio. A single injection of mTNF alpha along with inactivated HSV1 allowed a twice higher antibody titer and a fourfold higher T-cell response as compared with immunization with HSV1 alone. Double immunization with both pDNAgD and pDNAmTNF increased the titer of anti-HSV1 antibodies and the T-cell response by factors of 8 and 1.5, respectively, as compared with immunization with pDNAgD alone. However, the protective effect was significantly lower with the two plasmids than with pDNAgD (73 vs. 100%). Thus, DNA immunization with pDNAgD induced both B- and T-cell responses and completely protected mice from a lethal doze of HSV1. The adjuvant properties of mTNF alpha and pDNAmTNF need further investigation.     

Alterations of Antioxidant and Oxygen Transport Properties of Blood in Adenocarcinoma-Bearing Mice during Chemotherapy

The influence of murine intestinal adenocarcinoma on the antioxidant status and hemoglobin content in the blood was analyzed. Murine adenocarcinoma was accompanied with a decrease of the nonprotein thiol concentration and an increase in ceruloplasmin. A conformational change in the globin molecule but not in the heme group was revealed in the hemoglobin molecule. The changes in the protein appear to be caused by nonspecific damage that results from the processes of peroxidation.     

ONTOGENETIC NICHE SHIFT IN THE BRACHIOPOD TEREBRATALIA TRANSVERSA: RELATIONSHIP BETWEEN THE LOSS OF ROTATION ABILITY AND ALLOMETRIC GROWTH

Abstract: Many articulated brachiopods experience marked life habit variations during ontogeny because they experience their fluid environment at successively higher Reynolds numbers, and they can change the configuration of their inhalant and exhalant flows as body size increases. We show that the extant brachiopod Terebratalia transversa undergoes a substantial ontogenetic change in reorientation governed by rotation around the pedicle. T. transversa′s reorientation angle (maximum ability to rotate on the pedicle) decreases during ontogeny, from 180 degrees in juveniles to 10–20 degrees in individuals exceeding 5 mm, to complete cessation of rotation in individuals larger than 10 mm. Rotation ability is substantially reduced after T. transversa achieves the adult lophophore configuration and preferred orientation with respect to ambient water currents at a length of 2.5–5 mm. We hypothesize that the rotation angle of T. transversa is determined mainly by the position of ventral and dorsal points of attachment of dorsal pedicle muscles relative to the pedicle. T. transversa shows a close correlation between the ontogenetic change in reorientation angle and ontogeny of morphological traits that are related to points of attachment of dorsal pedicle muscles, although other morphological features can also limit rotation in the adult stage. The major morphological change in cardinalia shape and the observed reduction of rotation affect individuals 2.5–10 mm in length. The position of ventral insertions of dorsal pedicle muscles remains constant, but contraction of dorsal pedicle muscles is functionally handicapped because dorsal insertions shift away from the valve midline, rise above the dorsal valve floor, and become limited by a wide cardinal process early in ontogeny (<5 mm). The rate of increase of cardinal process width and of distance between dorsal pedicle muscle scars substantially decreases in the subadult stage (5–10 mm), and most of the cardinalia shell traits grow nearly isometrically in the adult stage (>10 mm). T. transversa attains smaller shell length in crevices than on exposed substrates. The proportion of small‐sized individuals and population density is lower on exposed substrates than in crevices, indicating higher juvenile mortality on substrates prone to grazing and physical disturbance. The loss of reorientation ability can be a consequence of morphological changes that strengthen substrate attachment and maximize protection against biotic or physical disturbance (1) by minimizing torques around the pedicle axis and/or (2) by shifting energy investments into attachment strength at the expense of the cost involved in reorientation.     

Hemolytic activity of hybrid antioxidants Ichphans

The hemolytic activity of new spatially hindered hybrid antioxidants—Ichphans—has been studied. The concentration-dependent hemolytic action of high concentrations of Ichphans with 8, 10, 12, or 16 carbon atoms in the aliphatic chain has been revealed. A nonmonotonic dependence of the hemolytic activity on the hydrophobic properties of Ichphans has been found.     

The effect of synthetic antioxidants,anphen derivatives,on erythrocyte morphology

The effect of new synthetic antioxidants, anphens, on erythrocyte morphology was studied. Insignificant cell transformations induced by the hydrophilic derivative of anphen-1 into echinocytes, as well as cell transformations into stomatocytes under the action of hydrophobic derivatives of anphens-2, 3, and 4 were revealed. The data we obtained indicate the intercalation of these compounds into the erythrocyte membrane. The distribution of compounds in the intra-membrane space depends on their hydrophobicity. A hydrophilic compound, anphen-1, is predominantly located in the outer monolayer of the membrane, while hydrophobic derivatives occur in the inner monolayer. It is proposed that the biological activities of anphen-3 and anphen-4 can occur in both monolayers as they move through the membrane, while the hydrophilic compound, anphen-1, exerts an insignificant membranotropic effect and can act only in the outer monolayer of the membrane. Variability in the efficiency of the concentration-dependent modifying action of the compounds with different hydrophobic properties has been found.