Utilization of restaurant waste oil as a precursor for sophorolipid production

Approximately 100 billion liters of oil is generated per week as waste from restaurants around the country. Because of health, environmental, and economic factors, current methods of disposal are ineffective for disposal of the restaurant oil wastes. In this study we have investigated the ability of Candida bombicola to fermentatively transform the restaurant oil waste into glycolipids called sophorolipids. Batch and fed-batch studies were carried out using oil waste as the lipid feedstock in Erlenmeyer flasks and in a fermentor. Batch fermentation in a fermentor gave the highest yield of sophorolipids of 34 g L-1. Fermentation using oleic acid as control feedstock were also carried out. Batch fermentation in the fermentor using this pure fatty acid gave a highest yield of 42 g L-1. The difference in the sophorolipid yield was attributed to the fatty acid composition of restaurant oil waste.     

Characterizing Mutational Signatures in Human Cancer Cell Lines Reveals Episodic APOBEC Mutagenesis

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Deletion of hypoxia-inducible factor prolyl 4-hydroxylase 2 in FoxD1-lineage mesenchymal cells leads to congenital truncal alopecia

Hypoxia-inducible factors (HIFs) induce numerous genes regulating oxygen homeostasis. As oxygen sensors of the cells, the HIF prolyl 4-hydroxylases (HIF-P4Hs) regulate the stability of HIFs in an oxygen-dependent manner. During hair follicle (HF) morphogenesis and cycling, the location of dermal papilla (DP) alternates between the dermis and hypodermis and results in varying oxygen levels for the DP cells. These cells are known to express hypoxia-inducible genes, but the role of the hypoxia response pathway in HF development and homeostasis has not been studied. Using conditional gene targeting and analysis of hair morphogenesis, we show here that lack of Hif-p4h-2 in Forkhead box D1 (FoxD1)-lineage mesodermal cells interferes with the normal HF development in mice. FoxD1-lineage cells were found to be mainly mesenchymal cells located in the dermis of truncal skin, including those cells composing the DP of HFs. We found that upon Hif-p4h-2 inactivation, HF development was disturbed during the first catagen leading to formation of epithelial-lined HF cysts filled by unorganized keratins, which eventually manifested as truncal alopecia. Furthermore, the depletion of Hif-p4h-2 led to HIF stabilization and dysregulation of multiple genes involved in keratin formation, HF differentiation, and HIF, transforming growth factor β (TGF-β), and Notch signaling. We hypothesize that the failure of HF cycling is likely to be mechanistically caused by disruption of the interplay of the HIF, TGF-β, and Notch pathways. In summary, we show here for the first time that HIF-P4H-2 function in FoxD1-lineage cells is essential for the normal development and homeostasis of HFs.     

Completeness of NOEs in protein structures: A statistical analysis of NMR data

The completeness of experimentally observed NOE restraints of a set of 97 NMR protein structures deposited in the PDB has been assessed. Completeness is defined as the ratio of the number of experimentally observed NOEs and the number of 'expected NOEs'. A practical definition of 'expected NOEs' based on inter-proton distances in the structures up to a given cut-off distance is proposed. The average completeness for the set of 97 structures is 68, 48, and 26% up to 3, 4, and 5 Å cut-off distances, respectively. For recent state-of-the-art structures these numbers are approximately 90, 75, and 45%. Almost 20% of the observed NOEs are between atoms that are further than 5 Å apart in the final structures. The completeness is independent of the relative surface accessibility and does not depend strongly on residue type, secondary structure or local precision, although the number of observed NOEs in these classes varies considerably. The completeness of NOE restraints is a useful quality criterion in the course of structure refinement. The completeness per residue is more informative than the number of NOEs per residue, which makes it a useful tool to assess the quality of the NMR data set in relation to the resulting structures.     

Stereoselective inhibition of glutamate carboxypeptidase by organophosphorus derivatives of glutamic acid

A series of alkyl and aryl phosphonyl, thiophosphonyl, and dithiophosphonyl derivatives of (S)- and (R)-glutamic acid were prepared and examined for inhibitory potency against glutamate carboxypeptidase (carboxypeptidase G). The acquisition of the phosphonamidodithioic acids and the individual phosphonamidothioic acid diastereomers was achieved through a common phosphonamidothiolate precursor, which also allowed for the chromatographic resolution of the chiral phosphorus center of the phosphonamidothioic acids. The most potent inhibitor of the series was the n-butylphosphonamidate derivative of the natural isomer of glutamic acid. Although each diastereomeric pair of three phosphonamidothionates exhibited stereoselective inhibition consistent with the configuration of the chiral phosphorus center, this effect was generally not remarkable. More important, was the effect of carbon stereochemistry upon glutamate carboxypeptidase inhibition as exemplified by a limited series of enantiomeric pairs of phosphonamidate and phosphonamidodithionate derivatives of glutamic acid. The phosphonamidate analogs derived from the unnatural stereoisomer of glutamic acid were devoid of inhibitory potency in contrast to their enantiomers. Surprisingly, the phosphonamidodithionates derived from the unnatural stereoisomer of glutamic acid demonstrated greater inhibitory potency than their naturally-derived antipodes.     

Allogeneic T cells treated with amotosalen prevent lethal cytomegalovirus disease without producing graft-versus-host disease following bone marrow transplantation

Infusion of donor antiviral T cells can provide protective immunity for recipients of hemopoietic progenitor cell transplants, but may cause graft-vs-host disease (GVHD). Current methods of separating antiviral T cells from the alloreactive T cells that produce GVHD are neither routine nor rapid. In a model of lethal murine CMV (MCMV) infection following MHC-mismatched bone marrow transplantation, infusion of MCMV-immune donor lymphocytes pretreated with the DNA cross-linking compound amotosalen prevented MCMV lethality without producing GVHD. Although 95% of mice receiving 30 x 10(6) pretreated donor lymphocytes survived beyond day +100 without MCMV disease or GVHD, all mice receiving equivalent numbers of untreated lymphocytes rapidly died of GVHD. In vitro, amotosalen blocked T cell proliferation without suppressing MCMV peptide-induced IFN-gamma production by MCMV-primed CD8(+) T cells. In vivo, pretreated lymphocytes reduced hepatic MCMV load by 4-log(10) and promoted full hemopoietic chimerism. Amotosalen-treated, MCMV tetramer-positive memory (CD44(high)) CD8(+) T cells persisted to day +100 following infusion, and expressed IFN-gamma when presented with viral peptide. Pretreated T cells were effective at preventing MCMV lethality over a wide range of concentrations. Thus, amotosalen treatment rapidly eliminates the GVHD activity of polyclonal T cells, while preserving long-term antiviral and graft facilitation effects, and may be clinically useful for routine adoptive immunotherapy.     

Rapid phagocytosis and melanization of bacteria and Plasmodium sporozoites by hemocytes of the mosquito Aedes aegypti

Mosquitoes are vectors of many deadly and debilitating pathogens. In the current study, we used light and electron microscopies to study the immune response of Aedes aegypti hemocytes to bacterial inoculations, Plasmodium gallinaceum natural infections, and latex bead injections. After challenge, mosquitoes mounted strong phagocytic and melanization responses. Granulocytes phagocytosed bacteria singly or pooled them inside large membrane-delimited vesicles. Phagocytosis of bacteria, Plasmodium sporozoites, and latex beads was extensive; we estimated that individual granulocytes have the capacity to phagocytose hundreds of bacteria and thousands of latex particles. Oenocytoids were also seen to internalize bacteria and latex particles, although infrequently and with low capacity. Besides phagocytosis, mosquitoes cleared bacteria and sporozoites by melanization. Interestingly, the immune response toward 2 species of bacteria was different; most Escherichia coli were phagocytosed, but most Micrococcus luteus were melanized. Similar to E. coli, most Plasmodium sporozoites were phagocytosed. The immune response was rapid; phagocytosis and melanization of bacteria began as early as 5 min after inoculation. The magnitude and speed of the cellular response suggest that hemocytes, acting in concert with the humoral immune response, are the main force driving the battle against foreign invaders.     

Mitochondrial localization of Smad5 in a human chondrogenic cell line

Bone morphogenetic proteins (BMPs) are members of the transforming growth factor-beta (TGF-beta) superfamily and regulate the formation of cartilage and bone tissues as well as other key events during development. TGF-beta superfamily signaling is mediated intracellularly by Smad proteins, some of which can translocate into the cell nucleus and influence gene expression. Although much progress has been made in understanding how TGF-beta superfamily signaling regulates expression of target genes, little formal proof has been presented regarding the intracellular distribution of the Smad proteins before their entry into the nucleus. In the literature, non-nuclear Smad proteins are generally referred to as cytoplasmic. Using confocal microscopy, we here show for the first time that immunofluorescent labeling of Smad5, one of the Smad proteins associated with BMP signaling, colocalizes with the mitochondrion-specific probe MitoTracker, demonstrating a mitochondrial distribution of Smad5 in non-stimulated chondroprogenitor cells.