Oils from perennial gourds

Summary The seeds and the oil from the seeds of two perennial gourds,Cucurbita palmata andCucurbita digitata, which grow wild in the Southwestern States, have been examined. Approximately two-thirds, by weight, of the whole dried fruit is seeds. The seeds contain about 28–30% oil and somewhat higher percentages of protein. The oils from both species are chiefly characterized by 10.0 to 17.0% of a conjugated trienoic acid similar to the eleostearic acid of tung oil, but apparently not identical with it. Analytical data are shown pertaining to the whole seeds as well as the oil extracted from them. Presented at the 38th Annual Meeting of the American Oil Chemists' Society, New Orleans, La., May 20–22, 1947. One of the laboratories of the Bureau of Agricultural and Industrial Chemistry, Agricultural Research Administration, U. S. Department of Agriculture.     

Chemical Synthesis of A Pore‐Forming Antimicrobial Protein,Caenopore‐5, by Using Native Chemical Ligation at a Glu‐Cys Site

The 2014 report from the World Health Organization (WHO) on antimicrobial resistance revealed an alarming rise in antibiotic resistance all around the world. Unlike classical antibiotics, with the exception of a few species, no acquired resistance towards antimicrobial peptides (AMPs) has been reported. Therefore, AMPs represent leads for the development of novel antibiotics. Caenopore‐5 is constitutively expressed in the intestine of the nematode Caenorhabditis elegans and is a pore‐forming AMP. The protein (82 amino acids) was successfully synthesised by using Boc solid‐phase peptide synthesis and native chemical ligation. No γ‐linked by‐product was observed despite the use of a C‐terminal Glu‐thioester. The folding of the synthetic protein was confirmed by ¹H NMR spectroscopy and circular dichroism and compared with data recorded for recombinant caenopore‐5. The permeabilisation activities of the protein and of shortened analogues were evaluated.     

Replication Protein A Enhances Kinetics of Uracil DNA Glycosylase on ssDNA and Across DNA Junctions: Explored with a DNA Repair Complex Produced with SpyCatcher/SpyTag Ligation

DNA repair proteins participate in extensive protein−protein interactions that promote the formation of DNA repair complexes. To understand how complex formation affects protein function during base excision repair, we used SpyCatcher/SpyTag ligation to produce a covalent complex between human uracil DNA glycosylase (UNG2) and replication protein A (RPA). Our covalent “RPA−Spy−UNG2” complex could identify and excise uracil bases in duplex areas next to ssDNA−dsDNA junctions slightly faster than the wild-type proteins, but this was highly dependent on DNA structure, as the turnover of the RPA−Spy−UNG2 complex slowed at DNA junctions where RPA tightly engaged long ssDNA sections. Conversely, the enzymes preferred uracil sites in ssDNA where RPA strongly enhanced uracil excision by UNG2 regardless of ssDNA length. Finally, RPA was found to promote UNG2 excision of two uracil sites positioned across a ssDNA−dsDNA junction, and dissociation of UNG2 from RPA enhanced this process. Our approach of ligating together RPA and UNG2 to reveal how complex formation affects enzyme function could be applied to examine other assemblies of DNA repair proteins.     

Synergistic inhibition of Listeria monocytogenes in vitro through the combination of octanoic acid and acidic calcium sulfate

It has been hypothesized that inhibition of foodborne pathogens can be enhanced by using antimicrobials in combination. A broth dilution assay was devised to determine whether inhibition of Listeria monocytogenes exposed to the combination of the fatty acid octanoic acid (OCT) and the organic acid-containing antimicrobial acidic calcium sulfate (ACS) was enhanced compared with the inhibition of the pathogen exposed to either antimicrobial applied singly. MICs for OCT and ACS were 25.00 μg/g and 1.56 ml/liter, respectively, for all strains of the pathogen tested. Fractional inhibitory concentrations (FICs) from the combination exposures were calculated for use in characterizing the antimicrobial interaction as antagonistic, additive indifferent, or synergistic with respect to L. monocytogenes inhibition. Combining OCT and ACS resulted in observed synergistic inhibition of L. monocytogenes; isobolograms for all strains curved toward the origin, and FIC indices (FIC(I)s) were <1.0. Future investigations of the antimicrobial combination should focus on determining the mechanism of action of combined antimicrobials and the levels of antimicrobials required for pathogen inhibition on the surfaces of ready-to-eat meats.     

Efficient stockpiling and shipping policies for humanitarian relief: UNHCR��s inventory challenge

The United Nations High Commissioner for Refugees (UNHCR) establishes and maintains refugee camps to meet the needs of 34.5 million people affected by disaster or war worldwide. Like other international humanitarian organizations, UNHCR maintains central stockpiles which supply these refugee operations. Management at UNHCR seeks to improve the timeliness and quality of its disaster response subject to its budget constraints. We develop an inventory model to analyze the interaction between a stockpile and a downstream refugee camp or relief operation. We consider two inventory decisions: first, how to partition a fixed budget between stockpiling and shipping costs in order to best meet the needs of beneficiaries; and second, given the shipping budget determined by the budget partition, how to ship relief items from the stockpile to a downstream relief operation in an efficient manner. We solve for the shipment policy using dynamic programming, then determine the optimal stockpile size given knowledge of the optimal shipment policy. The optimization balances a key tradeoff: a larger stockpile is costly to procure and maintain, but enhances a humanitarian organization’s ability to respond to relief operation demands. We provide insights into shipment strategies and stockpile size. We also develop a spreadsheet model to help humanitarian organizations in their operational decision-making, leading to improved response to beneficiaries. Humanitarian organizations must use their financial resources wisely to carry out their mandates, and models of this type can help them make the best use of their limited response resources.