The influence of coal ash and thermal discharges upon the distribution and bioaccumulation of aquatic invertebrates

The distribution, density and uptake of twenty elements by aquatic invertebrates inhabiting a drainage system, that received excessive coal ash effluent (275 JTU of turbidity) at one end and thermal loading (44.5°C) at the other end, was studied for 15 months. The ash settling basin filled during the first eight months of sampling which resulted in the release of ash effluent directly into the receiving system. Density of invertebrates was lowest in the 300 m stream between the ash basin and swamp and highest 1200 m beyond the stream-swamp confluence where ash influence was minimal. Invertebrate density was lowest in the stations where turbidity from ash effluent was greatest. The most tolerant invertebrates to coal ash stress were odonates (Libellula sp. and Enallagma sp.), crayfish (Procambarus sp.), amphipods (Gammarus sp.) and gastropods (Physa. sp.), and midges (Chironomidae) when the basin was filling. During the period of ash overflow, all groups were either reduced in numbers or absent. In the thermally stressed station, Libellula sp. was the predominant invertebrate sampled when water temperature ranged from 25.5–45.5°C (257-1=28.7°C) all aquatic invertebrates were limited in numbers and density when temperature exceeded the lower and upper ranges of 10.0–38.0°C.This research was supported by AEC Contract AT (38-1-824)This research was supported by AEC Contract AT (38-1-824)     

Free cytoplasmic messenger ribonucleoprotein complexes from rabbit reticulocytes

Free cytoplasmic globin mRNA containing mRNP-particles were isolated from rabbit reticulocytes by zonal sucrose gradient centrifugation and their properties were compared with mRNP particles isolated in the same way from EDTA-dissociated reticulocyte polyribosomes. The average poly(A)-length of 9S mRNA from free cytoplasmic mRNP was 17–20 nucleotides being about two times shorter than the average poly(A)-length of polysomal 9S mRNA. The protein composition of the free cytoplasmic mRNP particles disclosed the absence of the 76,000 dalton protein which is associated with the 3poly(A)-segment of polysomal globin mRNA. It was concluded that free cytoplasmic mRNP-particles from rabbit reticulocytes can be classified as old mRNP in a post-translational phase. Free cytoplasmic mRNPs were translated in heterologous cell-free systems as well as in Xenopus laevis oocytes. Addition of hemin stimulated the synthesis of -globin in all systems, while the presence of the cap analogue m⁷G(5)p inhibited translation of free cytoplasmic mRNA completely. The latter finding suggested that free cytoplasmic mRNA has a 5 terminal cap. Shortening of the poly(A)-segment with concomitant loss of the 76,000 dalton protein may lead to less efficient translation of free cytoplasmic mRNP.     

High capacity gel preparative electrophoresis for purification of fragments of genomic DNA

We have designed a high-capacity gel electrophoretic device for the purification of large amounts of restriction endonuclease fragments of genomic DNA. This device exploits the high resolution of gel electrophoresis in conjunction with an electronic system permitting discontinuous sample elution over a large gel surface area. This feature preserves resolution and greatly increases capacity and yield. The resulting DNA fractions may be used in restriction endonuclease, ligation, transfection, and transformation reactions without further extensive manipulation. Furthermore, DNA fragments of a broad size range are recovered with high efficiency from the gel.     

Preparation of (aryl α-l-idopyranosid)uronic acids

The earlier preparation of cyclohexylammonium (phenyl α-l-idopyranosid)-uronate has been improved, and (4-methylumbelliferyl α-l-idopyranosid)uronic acid (14), a more sensitive substrate for α-l-iduronidase, has been synthesized by an analogous route. Zinc chloride-catalyzed condensation of 4-methylumbelliferone with 1,2,3,4,6-penta-O-acetyl-α-l-idopyranose (4) in 1,2-ethanediol diacetate gave crystalline 4-methylumbelliferyl 2,3,4,6-tetra-O-acetyl-α-l-idopyranoside (7). O-Deacetylation and catalytic oxidation gave 14, characterized as a cyclohexylammonium salt. The starting material 4 was prepared, in 21 % yield from l-glucose, by conversion of the intermediate 1,2,3,4,6-penta-O-acetyl-β-l-glucopyranose to 2,3,4,6-tetra-O-acetyl-β-l-glucopyranosyl chloride and acetoxonium ion rearrangement, as described for the D-series.     

Preparation of (aryl α-l-idopyranosid)uronic acids

The earlier preparation of cyclohexylammonium (phenyl α-l-idopyranosid)-uronate has been improved, and (4-methylumbelliferyl α-l-idopyranosid)uronic acid (14), a more sensitive substrate for α-l-iduronidase, has been synthesized by an analogous route. Zinc chloride-catalyzed condensation of 4-methylumbelliferone with 1,2,3,4,6-penta-O-acetyl-α-l-idopyranose (4) in 1,2-ethanediol diacetate gave crystalline 4-methylumbelliferyl 2,3,4,6-tetra-O-acetyl-α-l-idopyranoside (7). O-Deacetylation and catalytic oxidation gave 14, characterized as a cyclohexylammonium salt. The starting material 4 was prepared, in 21 % yield from l-glucose, by conversion of the intermediate 1,2,3,4,6-penta-O-acetyl-β-l-glucopyranose to 2,3,4,6-tetra-O-acetyl-β-l-glucopyranosyl chloride and acetoxonium ion rearrangement, as described for the D-series.     

A Chromosomal Translocation Causing Overproduction of Iso-2-Cytochrome c in Yeast

The CYC7–1 mutation in the yeast Saccharomyces cerevisiae causes the production of approximately 30 times the normal amount of iso-2-cytochrome c. Genetic analysis established that the CYC7–1 mutation is a reciprocal translocation involving the left arm of chromosome V and the right arm of chromosome XVI. The chromosome V arm was broken adjacent to the gene CYC7, which determines the primary structure of iso-2-cytochrome c, and this fragment containing the CYC7 gene was joined to the segment of chromosome XVI. It appears as though the elevation of iso-2-cytochrome c is caused by an abnormal controlling region adjacent to the structural region of the CYC7 gene.     

Identification of a soluble protein stimulator of plasmalogen biosynthesis and stearoyl-coenzyme a desaturase

Stimulation of the desaturation of 1-alkyl-2-acyl-sn-glycero-3-phosphoethanolamine (GPE), which forms ethanolamine plasmalogens, by a component of the 105,000g supernatant has been previously reported. We have isolated the stimulatory protein and identified it as catalase. Purified rat liver catalase or commercial bovine liver catalase is as effective in stimulating microsomal 1-alkyl-2-acyl-GPE desaturation as the soluble proteins. The stimulatory effect of these proteins is eliminated by catalase inhibitors. It appears that catalase stimulates the desaturation of 1-alkyl-2-acyl-GPE by preventing inactivation of the enzyme system by H₂O₂ or a decomposition product of H₂O₂. The cytochrome b₅ content and NADH oxidation are depressed in Fischer R-3259 sarcoma microsomes by H₂O₂; this effect is eliminated by catalase. However, since measurable inhibition of 1-alkyl-2-acyl-GPE desaturase by H₂O₂ still occurred in the presence of catalase, the inhibition by H₂O₂ cannot be explained solely on the basis of cytochrome b₅ inactivation. The desaturation of stearoyl-coenzyme A, a reaction analogous in many respects to 1-alkyl-2-acyl-GPE desaturation, was also found to be stimulated by catalase.     

A synthesis of methyl 4,6-di-O-Methyl-α-d-mannopyranoside

A new route is described for preparing methyl 4,6-di-O-methyl-α-d-mannopyranoside (5) via methyl 2,3-di-O-p-tolylsulfonyl-α-d-mannopyranoside (3) as an intermediate. The retention of the mannopyranoside configuration and ring form was confirmed by proton n.m.r. spectroscopy and by m.s. of peracetylated aldononitrile derivatives. Mass-spectral fragmentation-pathways previously proposed were confirmed for 5-O-acetyl-2,3,4,6-tetra-O-methyl-, 2,5-di-O-acetyl-3,4,6-tri-O-methyl-, and 3,5-di-O-acetyl-2,4,6-tri-O-methyl-d-mannononitrile.     

The role of cell membrane in the antiviral effect of interferon

The mechanism of interferon action in human fibroblasts has been studied by use of both antisera to human fibroblast interferon and the antisera to the surface of human fibroblast cell. The anti-interferon serum completely neutralized the antiviral effect of human fibroblast interferon. Interferon antiserum prevented the intracellular antiviral state from developing when added to the medium of the cells in which interferon synthesis had already been induced by poly (I · C). This suggests that development of the antiviral state involves interferon interaction with the external part of the producing cell. Treatment with the serum directed against the surface of human fibroblast cells failed to inhibit the antiviral activity of human interferon in these cells. In addition, the effect of gangliosides on the antiviral activity of human interferon was studied and it was found that human interferon binds to gangliosides and that this interaction leads to inactivation of the antiviral effect of interferon. Pretreatment of human fibroblasts with gangliosides had no effect on the sensitivity of these cells to exogenous interferon.