Quantitation of Residual Host Protein in Chicken Embryo-Derived Vaccines by Radial Immunodiffusion

Quantitation of soluble residual host protein in chicken embryo-derived vaccines was performed rapidly, economically, and accurately by radial immunodiffusion.     

Formation and dissimilation of oxalacetate and pyruvate Pseudomonas citronellolis grown on noncarbohydrate substrates.

Metabolism of lactate as a carbon source by Pseudomonas citronellolis occurred via a nicotinamide adenine dinucleotide (NAD)-independent L-lactate dehydrogenase, which was present in cells grown on DL-lactate but was not present in cells grown on acetate, aspartate, citrate, glucose, glutamate, or malate. The cells also possessed a constitutive, NAD-independent malate dehydrogenase instead of the conventional NAD-dependent malate dehydrogenase instead of the conventional NAD-dependent enzyme in the tricarboxylic acid cycle. Both enzymes were particulate and used dichlorophenolindo-phenol or oxygen as an electron acceptor. In acetate-grown cells, the activity of pyruvate dehydrogenase and NAD phosphate-linked malate enzyme decreased, cells grown on glucose or lactate. This was consistent with the need to maintain a supply of oxalacetate for metabolism of acetate via the tricarboxylic acid cycle. Changes in enzyme activities suggest that gluconeogenesis from noncarbohydrate carbon sources occurs via the malate enzyme (when oxalacetate decarboxylase is inhibited) or a combination of the NAD-independent malate dehydrogenase and oxalacetate decarboxylase.     

Evidence for a complex of three beta-oxidation enzymes in Escherichia coli: induction and localization.

The enzymes for beta-oxidation of fatty acids in inducible and constitutive strains of Escherichia coli were assayed in soluble and membrane fractions of disrupted cells by using fatty acid and acyl-coenzyme A (CoA) substrates containing either 4 or 16 carbon atoms in the acyl moieties. Cell fractionation was monitored, using succinic dehydrogenase as a membrane marker and glucose 6-phosphate dehydrogenase as a soluble marker. Acyl-CoA synthetase activity was detected exclusively in the membrane fraction, whereas acyl-CoA dehydrogenase, 3-hydroxyacyl-CoA dehydrogenase, enoyl-CoA hydratase, and 3-ketoacyl-CoA thiolase activities that utilized both C4 and C16 acyl-CoA substrates were isolated from the soluble fraction. 3-Hydroxyacyl-CoA dehydrogenase, enoyl-CoA hydratase, and 3-ketoacyl-CoA thiolase activities assayed with both C4 and C16 acyl-CoA substrates co-chromatographed on gel filtration and ion-exchange columns and cosedimented in glycerol gradients. The data show that these three enzyme activities of the fad regulon can be isolated as a multienzyme complex. This complex dissociates in very dilute preparations; however, in those preparations where the three activities are separated, the fractionated species retain activity with both C4 and C16 acyl-CoA substrates.     

Human immunodeficiency virus type 1 tropism for brain microglial cells is determined by a region of the env glycoprotein that also controls macrophage tropism.

Human immunodeficiency virus type 1 (HIV-1), the agent of AIDS, frequently infects the central nervous system. We inoculated adult human brain cultures with chimeric viruses containing parts of the env gene of a cloned primary isolate from brain tissue, HIV-1 JRFl, inserted into the cloned DNA of a T-cell-tropic strain. A chimeric virus containing the carboxy-terminal portion of HIV-1 JRFl env did not replicate in these brain tissue cultures, while a chimera expressing an env-encoded protein containing 158 amino acids of HIV-1 JRFl gp120, including the V3 loop, replicated well in brain microglial cells, as it does in blood macrophages. Infection of brain microglial cells with such a chimera was blocked by an antibody to the V3 loop of gp 120. Thus, env determinants in the region of gp120, outside the CD4-binding site and comprising the V3 loop, are critical for efficient viral binding to and/or entry into human brain microglia.     

The anabolic action of intermittent parathyroid hormone on cortical bone depends partly on its ability to induce nitric oxide‐mediated vasorelaxation in BALB/c mice

There is strong evidence that vasodilatory nitric oxide (NO) donors have anabolic effects on bone in humans. Parathyroid hormone (PTH), the only osteoanabolic drug currently approved, is also a vasodilator. We investigated whether the NO synthase inhibitor L‐NAME might alter the effect of PTH on bone by blocking its vasodilatory effect. BALB/c mice received 28 daily injections of PTH[1–34] (80 µg/kg/day) or L‐NAME (30 mg/kg/day), alone or in combination. Hindlimb blood perfusion was measured by laser Doppler imaging. Bone architecture, turnover and mechanical properties in the femur were analysed respectively by micro‐CT, histomorphometry and three‐point bending. PTH increased hindlimb blood flow by >30% within 10 min of injection (P < 0.001). Co‐treatment with L‐NAME blocked the action of PTH on blood flow, whereas L‐NAME alone had no effect. PTH treatment increased femoral cortical bone volume and formation rate by 20% and 110%, respectively (P < 0.001). PTH had no effect on trabecular bone volume in the femoral metaphysis although trabecular thickness and number were increased and decreased by 25%, respectively. Co‐treatment with L‐NAME restricted the PTH‐stimulated increase in cortical bone formation but had no clear‐cut effects in trabecular bone. Co‐treatment with L‐NAME did not affect the mechanical strength in femurs induced by iPTH. These results suggest that NO‐mediated vasorelaxation plays partly a role in the anabolic action of PTH on cortical bone. © 2016 The Authors. Cell Biochemistry and Function published by John Wiley & Sons, Ltd.     

Nuclear gene trees and the phylogenetic relationships of the mangabeys (Primates: Papionini)

Phylogenetic relationships of mangabeys within the Old World monkey tribe Papionini are inferred from analyses of nuclear DNA sequences from five unlinked loci. The following conclusions are strongly supported, based on congruence among trees derived for the five separate gene regions: (1) mangabeys are polyphyletic within the Papionini; (2) Cercocebus is the sister taxon to the genus Mandrillus; and (3) Lophocebus belongs to a clade with Papio and Theropithecus, with Papio as its most likely sister taxon. Morphologically based phylogenies positing mangabey monophyly were evaluated by mapping the sequences for each locus on these trees. The data seem to fit these trees poorly in both maximum-parsimony and likelihood analyses. Incongruence among nuclear gene trees occurred in the interrelationships among Lophocebus, Papio, and Theropithecus. Several factors that may account for this incongruence are discussed, including sampling error, random lineage sorting, and introgression.      

PPCMatrix: a PowerPC dotmatrix program to compare large genomic sequences against protein sequences

Summary : An interactive dotmatrix program for the MacOS was designed that allows comparison of DNA to protein sequences using nested 3-frame translations. Availability : Shareware, available at http://copan.bioz.unibas.ch/software/ Contact : burglin@ubaclu. unibas.ch