Erratum: Escherichia coli DnaE polymerase couples pyrophosphatase activity to DNA replication (PLoS ONE 11:4 (e0152915) DOI: 10.1371/journal.pone.0152915)

: [This corrects the article DOI: 10.1371/journal.pone.0152915.]

Herpes simplex virus (HSV) glycoprotein h is partially processed in a cell line that expresses the glycoprotein and fully processed in cells infected with deletion or is mutants in the known hsv glycoproteins

Cell lines that constitutively express herpes simplex virus 1 (HSV-1) glycoprotein H (gH-1 ) failed to synthesize the mature form of gH and accumulated a precursor-like form of the glycoprotein, which was retained intracellularly, most likely in RER. Fine-structure analysis of the oligosaccharides present in recombinant gH revealed oligosaccharides processed by RER enzymes; sialylated complex-type and biantennary oligosaccharides, which are assembled in the trans-Golgi, were absent. A small fraction had the characteristics of oligosaccharides processed by the early mannosidases of the Golgi. These findings suggest that a defect in the transport out of RER to the Golgi may account for the intracellular retention of the immature form of gH in cells that express the glycoprotein constitutively. Upon superinfection of cells expressing gH-1 with HSV-2, recombinant gH-1 underwent maturation, indicating that a viral function is required to attain full processing of gH. The known HSV glycoproteins do not appear to carry out this function, since in cells infected with deletion mutants in gD, gG, gE, and gE-gl, with a spontaneous gC- mutant, or with a temperature-sensitive mutant in gB, maturation of gH occurred independently of the presence or of the maturation of the single glycoproteins tested. The present findings together with previous observations on HSV, human CMV, and the EBV homologue of gH suggest that inability of gH to undergo full processing in the absence of viral protein (s) is a property of gH. © 1991

Manganese is a Deinococcus radiodurans growth limiting factor in rich culture medium

To understand the effects triggered by Mn2+ on Deinococcus radiodurans, the proteome patterns associated with different growth phases were investigated. In particular, under physiological conditions we tested the growth rate and the biomass yield of D. radiodurans cultured in rich medium supplemented or not with MnCl2. The addition of 2.5-5.0 µM MnCl2 to the medium neither altered the growth rate nor the lag phase, but significantly increased the biomass yield. When higher MnCl2 concentrations were used (10-250 µM), biomass was again found to be positively affected, although we did observe a concentration-dependent lag phase increase. The in vivo concentration of Mn2+ was determined in cells grown in rich medium supplemented or not with 5 µM MnCl2. By atomic absorption spectroscopy, we estimated 0.2 and 0.75 mM Mn2+ concentrations in cells grown in control and enriched medium, respectively. We qualitatively confirmed this observation using a fluorescent turn-on sensor designed to selectively detect Mn2+in vivo. Finally, we investigated the proteome composition of cells grown for 15 or 19 h in medium to which 5 µM MnCl2 was added, and we compared these proteomes with those of cells grown in the control medium. The presence of 5 µM MnCl2 in the culture medium was found to alter the pI of some proteins, suggesting that manganese affects post-translational modifications. Further, we observed that Mn2+ represses enzymes linked to nucleotide recycling, and triggers overexpression of proteases and enzymes linked to the metabolism of amino acids

Cafeteria Diet Inhibits Insulin Clearance By Reduced Insulin-degrading Enzyme Expression And Mrna Splicing.

Insulin clearance plays a major role in glucose homeostasis and insulin sensitivity in physiological and/or pathological conditions, such as obesity-induced type 2 diabetes as well as diet-induced obesity. The aim of the present work was to evaluate cafeteria diet-induced obesity-induced changes in insulin clearance and to explain the mechanisms underlying these possible changes. Female Swiss mice were fed either a standard chow diet (CTL) or a cafeteria diet (CAF) for 8 weeks, after which we performed glucose tolerance tests, insulin tolerance tests, insulin dynamics, and insulin clearance tests. We then isolated pancreatic islets for ex vivo glucose-stimulated insulin secretion as well as liver, gastrocnemius, visceral adipose tissue, and hypothalamus for subsequent protein analysis by western blot and determination of mRNA levels by real-time RT-PCR. The cafeteria diet induced insulin resistance, glucose intolerance, and increased insulin secretion and total insulin content. More importantly, mice that were fed a cafeteria diet demonstrated reduced insulin clearance and decay rate as well as reduced insulin-degrading enzyme (IDE) protein and mRNA levels in liver and skeletal muscle compared with the control animals. Furthermore, the cafeteria diet reduced IDE expression and alternative splicing in the liver and skeletal muscle of mice. In conclusion, a cafeteria diet impairs glucose homeostasis by reducing insulin sensitivity, but it also reduces insulin clearance by reducing IDE expression and alternative splicing in mouse liver; however, whether this mechanism contributes to the glucose intolerance or helps to ameliorate it remains unclear.219173-8