High performance liquid chromatography and fast atom bombardment mass spectrometry of unusual branched and unsaturated phospholipid molecular species

The unusual symmetrical molecular species 1,2-di-3,7,11,15-tetramethylhexadecanoyl-sn-glycero-3-phosphoglyce rol, 1,2-di-5,8,11,14-docosatetraenoyl-sn-glycero-3-phosphocholine, 1,2-di-5,9,19-octacosatrienoyl-sn-glycero-3-phosphoethanolamine, and 1,2-di-5,9,23-triacontatrienoyl-sn-glycero-3-phosphoethanolamine were isolated from the marine sponges Axinella verrucosa, Higginsia tethyoides, Tethya aurantia and Aplysina fistularis by HPLC and studied by fast atom bombardment (FAB) mass spectrometry. In addition to molecular weights, branching and double bonds were located in the fatty acyl chains of the intact phospholipid molecules, using FAB either in a positive or negative mode. Some mass spectral results were obtained on enriched phospholipid fractions rather than pure molecular species using MS/MS.     

Nature's role in sustaining economic development

In this paper, I formalize the idea of sustainable development in terms of intergenerational well-being. I then sketch an argument that has recently been put forward formally to demonstrate that intergenerational well-being increases over time if and only if a comprehensive measure of wealth per capita increases. The measure of wealth includes not only manufactured capital, knowledge and human capital (education and health), but also natural capital (e.g. ecosystems). I show that a country''s comprehensive wealth per capita can decline even while gross domestic product (GDP) per capita increases and the UN Human Development Index records an improvement. I then use some rough and ready data from the world''s poorest countries and regions to show that during the period 1970–2000 wealth per capita declined in South Asia and sub-Saharan Africa, even though the Human Development Index (HDI) showed an improvement everywhere and GDP per capita increased in all places (except in sub-Saharan Africa, where there was a slight decline). I conclude that, as none of the development indicators currently in use is able to reveal whether development has been, or is expected to be, sustainable, national statistical offices and international organizations should now routinely estimate the (comprehensive) wealth of nations.     

Binding of sulfobromophthalein to rat and human ligandins: characterization of a binding-site peptide

Photoaffinity techniques were employed to affect the covalent binding of [35S]sulfobromophthalein to proteins of rat and human liver cytosol. In rat liver cytosol at low concentrations, sulfobromophthalein bound to the 22 kDa subunit of ligandin. In human liver cytosol, binding to a 23.5 kDa subunit was observed. At higher concentrations, sulfobromophthalein also bound to 12, 23.5, 37, and 42 kDa peptides. When the peptides resulting from CNBr cleavage of [35S]sulfobromophthalein-ligandin complex were resolved by high-performance liquid chromatography, radioactivity was associated with two peptides. The peptide containing 80% of the radioactivity was isolated and characterized. Its molecular weight is 3.4 kDa, it contains the single tryptophan residue of ligandin and has a glutamate (glutamine) as the N-terminal amino acid.     

Histological and ultrastructural investigation of the female reproductive system of Argulus bengalensis Ramakrishna, 1951 (Crustacea: Branchiura)

In order to understand branchiuran reproductive biology, it is imperative to know the sites of oogenesis and oocyte maturation, locate the accessory reproductive glands, and identify the fertilization site with the present knowledge of the sperm transfer mechanism of the genus Argulus. With these objectives, we attempted to describe the female reproductive system of Argulus bengalensis using serial histological sections through the ovaries and associated ducts in the transverse, longitudinal, and sagittal planes. The reproductive organs include a median ovary, one pair of ovarian lumina, a median oviduct, and a pair of collateral accessory glands. A duct from each of the collateral accessory glands leads into the proximal part of the median oviduct, which opens to the exterior through a genital opening at the distal end. The glandular secretion presumably contributes to the jelly coat of the egg. The ovary is bound with a tunica propria which extends further diametrically inside the ovary forming the paired lumina. The lumina are confluent into the median oviduct. Two distinct areas, the germarium and differentiating zones, are clearly distinguishable within the ovary. The tunica propria itself houses the oogonia within a matrix, serving as the germarium. Transmission electron micrograph reveals that the matrix is made of collagen. The collagen matrix confers elasticity to the tunica propria to accommodate the postvitellogenic oocytes within the ovarian lumen. The differentiating zone is situated in between the germarium: dorsally it is covered with a chromatophore layer. The ovary is ensheathed by a circum ovarian striated muscle. The presence of spermatophores in the ovarian lumen indicates the fertilization site. J. Morphol. 277:707–716, 2016. © 2016 Wiley Periodicals, Inc.     

The host protein required for in vitro replication of poliovirus is a protein kinase that phosphorylates eukaryotic initiation factor-2

The HeLa cell protein (host factor) required for in vitro replication of poliovirus has been identified as a 67,000 dalton phosphoprotein. The purified protein displays three activities in vitro: stimulation of poliovirus RNA synthesis in the presence of poliovirus replicase, apparent self-phosphorylation, and phosphorylation of the alpha-subunit of eukaryotic protein synthesis initiation factor 2 (eIF-2). All three activities can be removed or inhibited by an antibody to host factor. Partially purified preparations of reticulocyte eIF-2 contain a similar phosphoprotein and display host factor activity in the viral RNA synthesis assay in vitro. In vitro phosphorylation of the 67 kd protein can be stimulated by low concentrations of double-stranded RNA. Addition of phosphorylated host factor in an in vitro RNA synthesis assay significantly changes the kinetics of viral RNA synthesis, indicating that protein phosphorylation may play an important role in viral RNA replication.     

Alterations of the Intracellular Peptidome in Response to the Proteasome Inhibitor Bortezomib

Bortezomib is an antitumor drug that competitively inhibits proteasome beta-1 and beta-5 subunits. While the impact of bortezomib on protein stability is known, the effect of this drug on intracellular peptides has not been previously explored. A quantitative peptidomics technique was used to examine the effect of treating human embryonic kidney 293T (HEK293T) cells with 5–500 nM bortezomib for various lengths of time (30 minutes to 16 hours), and human neuroblastoma SH-SY5Y cells with 500 nM bortezomib for 1 hour. Although bortezomib treatment decreased the levels of some intracellular peptides, the majority of peptides were increased by 50–500 nM bortezomib. Peptides requiring cleavage at acidic and hydrophobic sites, which involve beta-1 and -5 proteasome subunits, were among those elevated by bortezomib. In contrast, the proteasome inhibitor epoxomicin caused a decrease in the levels of many of these peptides. Although bortezomib can induce autophagy under certain conditions, the rapid bortezomib-mediated increase in peptide levels did not correlate with the induction of autophagy. Taken together, the present data indicate that bortezomib alters the balance of intracellular peptides, which may contribute to the biological effects of this drug.