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Plasmalogens are glycerophospholipids with a vinyl ether bond, rather than an ester bond, at sn-1 position. These lipids were described in anaerobic bacteria, myxobacteria, animals and some protists, but not in plants or fungi. Anaerobic and aerobic organisms synthesize plasmalogens differently. The aerobic pathway requires oxygen in the last step, which is catalyzed by PEDS1. CarF and TMEM189 were recently identified as the PEDS1 from myxobacteria and mammals, which could be of valuable use in exploring the distribution of this pathway in eukaryotes. We show the presence of plasmalogens in Capsaspora owczarzaki, one of the closest unicellular relatives of animals. This is the first report of plasmalogens in non-metazoan opisthokontas. Analysis of its genome revealed the presence of enzymes of the aerobic pathway. In a broad BLAST search, we found PEDS1 homologs in Opisthokonta and some genera of Amoebozoa and Excavata, consistent with the restricted distribution of plasmalogens reported in eukaryotes. Within Opisthokonta, PEDS1 is limited to Filasterea (Capsaspora and Pigoraptor), Metazoa and a small group of fungi comprising three genera of ascomycetes. A phylogenetic analysis of PEDS1 traced the acquisition of plasmalogen synthesis in animals to a filasterean ancestor and suggested independent acquisition events for Amoebozoa, Excavata and Ascomycetes.

A new objective and standardized method for early determination of firmness of the intact pork belly in a research environment is described, and compared to the existing bar-bend method. The belly characteristics that contribute to the outcome of each method, and the relationship between the two methods are identified. • Original method requires a ribbed pork belly, and several minutes relaxation time. • New method provides an immediate measurement on an intact belly. • Advantages include early, rather than late, application in the fabrication process; rapid measurement; standardization; measurements minimally affected by animal length or belly length.

The 7-azabicyclo[4.3.1]decane ring system, common to a number of biologically active alkaloids, was accessed from tropone (via its η4-diene complex with Fe(CO)3) in a short sequence of steps: 1) nucleophilic amine addition and subsequent Boc-protection, 2) photochemical demetallation of the iron complex, and 3) an intramolecular Heck reaction. Minor modifications to the protocol enabled access to the related 2-azabicyclo[4.4.1]undecane system, albeit in lower yield.

Abstract The ciliate Tetrahymena thermophila can either synthesize tetrahymanol or when available, assimilate and modify sterols from its diet. This metabolic shift is mainly driven by transcriptional regulation of genes for tetrahymanol synthesis (TS) and sterol bioconversion (SB). The mechanistic details of sterol uptake, intracellular trafficking and the associated gene expression changes are unknown. By following cholesterol incorporation over time in a conditional phagocytosis-deficient mutant, we found that although phagocytosis is the main sterol intake route, a secondary endocytic pathway exists. Different expression patterns for TS and SB genes were associated with these entry mechanisms. Squalene synthase was down-regulated by a massive cholesterol intake only attainable by phagocytosis-proficient cells, whereas C22-sterol desaturase required ten times less cholesterol and was up-regulated in both wild-type and mutant cells. These patterns are suggestive of at least two different signaling pathways. Sterol trafficking beyond phagosomes and esterification was impaired by the NPC1 inhibitor U18666A. NPC1 is a protein that mediates cholesterol export from late endosomes/lysosomes in mammalian cells. U18666A also produced a delay in the transcriptional response to cholesterol, suggesting that the regulatory signals are triggered between lysosomes and the endoplasmic reticulum. These findings could hint at partial conservation of sterol homeostasis between eukaryote lineages.

The increase in market demand and economic value of Canadian pork primal cuts has led to a need to assess advanced technologies capable of measuring quality traits. Fat and lean composition were measured using a Tellspec near-infrared (NIR) spectroscopy device to predict the pork belly fat iodine value (IV) and loin lean intramuscular fat (IMF) content in 158 pork belly primals and 419 loin chops. The calibration model revealed a 90.6% and 88.9% accuracy for the Tellspec NIR to predict saturated fatty acids (SFA) and IV, respectively, in the belly fat. The calibration model accuracy for the other belly fatty acids revealed an accuracy of 66.3–86.1%. Using the Tellspec NIR to predict loin lean IMF reported a lower accuracy for moisture (R2 = 60) and fat % (R2 = 40.4). This suggests that Tellspec NIR spectroscopy measures on the pork belly primal offers a cost-efficient, rapid, accurate, and non-invasive indicator of pork belly IV and could be used for the classification for specific markets.

BackgroundHamburger is the most consumed beef product in North America, but lacks in nutritional appeal due to its high fat content and high proportion of saturated fatty acids (SFA). Objectives of the present study were to improve the FA profiles of hamburgers made with perirenal fat (PRF) and subcutaneous fat (SCF) when feeding steers different diets along with examining differences in sensory attributes and oxidative stability. Diets included a control diet containing 70:30 red clover silage: barley based concentrate, a diet containing sunflower-seed (SS) substituted for barley, and diets containing SS with 15% wheat dried distillers' grain with solubles (DDGS-15) or 30% DDGS (DDGS-30). Hamburgers were made from triceps brachii and either PRF or SCF (80:20 w/w).ResultsPerirenal fat versus SCF hamburgers FA had 14.3% more (P 0.05), but feeding DDGS-30 diet reduced the proportions of (P

Commercial technologies for assessing meat quality may be useful for performing early in-line belly firmness classification. This study used 207 pork carcasses to measure predicted iodine value (IV) at the clear plate region of the carcass with an in-line near-infrared probe (NitFomTM), calculated IV of belly fat using wet chemistry methods, determined the belly bend angle (an objective method to measure belly firmness), and took dimensional belly measurements. A regression analysis revealed that NitFomTM predicted IV (R2 = 0.40) and belly fat calculated IV (R2 = 0.52) separately contributed to the partial variation of belly bend angle. By testing different NitFomTM IV classification thresholds, classifying soft bellies in the 15th percentile resulted in 5.31% false negatives, 5.31% false positives, and 89.38% correctly classified soft and firm bellies. Similar results were observed when the classification was based on belly fat IV calculated from chemically analyzed fatty acid composition. By reducing the level of stringency on the percentile of the classification threshold, an increase in false positives and decrease in false negatives was observed. This study suggests the IV predicted using the NitFomTM may be useful for early in-line presorting of carcasses based on expected belly firmness, which could optimize profitability by allocating carcasses to specific cutout specifications.

Little is known about the structure-function relationship of membrane-bound lipid desaturases. Using a domain-swapping strategy, we found that the N terminus (comprising the two first transmembrane segments) region of Bacillus cereus DesA desaturase improves Bacillus subtilis Des activity. In addition, the replacement of the first two transmembrane domains from Bacillus licheniformis inactive open reading frame (ORF) BL02692 with the corresponding domain from DesA was sufficient to resurrect this enzyme. Unexpectedly, we were able to restore the activity of ORF BL02692 with a single substitution (Cys40Tyr) of a cysteine localized in the first transmembrane domain close to the lipid–water interface. Substitution of eight residues (Gly90, Trp104, Lys172, His228, Pro257, Leu275, Tyr282, and Leu284) by site-directed mutagenesis produced inactive variants of DesA. Homology modeling of DesA revealed that His228 is part of the metal binding center, together with the canonical His boxes. Trp104 shapes the hydrophobic tunnel, whereas Gly90 and Lys172 are probably involved in substrate binding/recognition. Pro257, Leu275, Tyr282, and Leu284 might be relevant for the structural arrangement of the active site or interaction with electron donors. This study reveals the role of the N-terminal region of Δ5 phospholipid desaturases and the individual residues necessary for the activity of this class of enzymes.

The objective of this study was to evaluate the performance of different low-cost instruments to measure pork colour in comparison to Minolta spectrophotometers and industry subjective standards. Canadian pork colour standards and commercial meat (252 loin chops and 46 tenderloins) were measured using two Minolta (CM 700D) spectrophotometers, four Nix sensors (two Nix Pro II and two Nix QC), and four Spectro devices (two Spectro 1 and two Spectro 1 Pro). Using Bland-Altman plots, all hand-held devices revealed similar performance on colour coordinates, except for the Nix Pro II, which had more variability on a* value, and Spectro 1 Pro on b* value, when compared to Minolta measurements. Low RSD values (< 5%) were obtained from repeated measurements on Canadian colour standards. The trend of colour coordinates on colour scores (0–6) were similar for all four commercial instruments, except for a* from Nix Pro and b* from Spectro 1. The correlation coefficients between subjective standards and colour coordinates from the Nix and Spectro devices were slightly higher than the Minolta spectrophotometers. Even though Nix and Spectro 1 series instruments generated different absolute colour coordinate values on meat samples, these pocket-size instruments presented great reliability to measure pork surface colour. However, operational limitations of the instruments, such as the internal calibration time between samples for the Spectro 1 series, should also be considered.

Carbocyclic nucleoside analogues are an essential class of antiviral agents and are commonly used in the treatment of viral diseases (hepatitis B, AIDS). Recently, we reported the racemic synthesis and the anti-human immunodeficiency virus activities (HIV) of 3′-fluoro-5′-norcarbocyclic nucleoside phosphonates bearing purines as heterocyclic base. Based on these results, the corresponding racemic norcarbocyclic nucleoside phosphonates bearing pyrimidine bases were synthesized. The prepared compounds were evaluated against HIV, but none of them showed marked antiviral activity compared to their purine counterparts.