Tetradecenoic Acid Research Articles

Pilot-Study to Explore Metabolic Signature of Type 2 Diabetes: A Pipeline of Tree-Based Machine Learning and Bioinformatics Techniques for Biomarkers Discovery.

This study aims to identify unique metabolomics biomarkers associated with Type 2 Diabetes (T2D) and develop an accurate diagnostics model using tree-based machine learning (ML) algorithms integrated with bioinformatics techniques. Univariate and multivariate analyses such as fold change, a receiver operating characteristic curve (ROC), and Partial Least-Squares Discriminant Analysis (PLS-DA) were used to identify biomarker metabolites that showed significant concentration in T2D patients. Three tree-based algorithms [eXtreme Gradient Boosting (XGBoost), Light Gradient Boosting Machine (LightGBM), and Adaptive Boosting (AdaBoost)] that demonstrated robustness in high-dimensional data analysis were used to create a diagnostic model for T2D. As a result of the biomarker discovery process validated with three different approaches, Pyruvate, D-Rhamnose, AMP, pipecolate, Tetradecenoic acid, Tetradecanoic acid, Dodecanediothioic acid, Prostaglandin E3/D3 (isobars), ADP and Hexadecenoic acid were determined as potential biomarkers for T2D. Our results showed that the XGBoost model [accuracy = 0.831, F1-score = 0.845, sensitivity = 0.882, specificity = 0.774, positive predictive value (PPV) = 0.811, negative-PV (NPV) = 0.857 and Area under the ROC curve (AUC) = 0.887] had the slight highest performance measures. ML integrated with bioinformatics techniques offers accurate and positive T2D candidate biomarker discovery. The XGBoost model can successfully distinguish T2D based on metabolites.

Evaluation of fatty acid-related nutritional quality indices in fried and raw nile tilapia, (Oreochromis Niloticus), fish muscles.

During frying, fat degrade and many reactions occur resulting in numerous altered fatty acid products. This would lead to the formation of Tran's fatty acids and changes in nutritional qualities. Hence, this study was aimed to determine the changes during frying on fatty acid composition of Nile tilapia (Oreochromis Niloticus) fish muscle from local fish market of Hawassa, Ethiopia. Fish fryers reported that they usually use palm oil for frying. They also indicated that the oil is kept for days and reused for frying at different cycle. In fried fish, 35 types of fatty acids were identified and 27 in raw fish muscle. Palmitic, stearic, heptadecanoic, and tetradecenoic acids were the abundant saturated fatty acids in both fried and raw fish muscle. Oleic, Docosahexaenoic, Eicosapentaenoic, and Linoleic acid were the major unsaturated fatty acids. The percentages of total saturated fatty acids (SFA) of raw fish muscle (47.4%) were found to be lower compared with fried fish muscle (51.8%). The n‐6/n‐3 ratio (7.83), index of atherogenicity (0.85), and thrombogenicity (1.71) in the fried fish muscle were in the undesirable values. The hypocholesterolemic/hypercholesterolemic ratio was relatively similar in the fried (1.09) and raw (1.02) fish muscles. The total unsaturated fatty acids (UFA) level of raw fish muscle (52.2%) was higher than the fried fish muscle (47.2%). Higher percentage of Tran's fatty acid was identified in the fried fish muscle compared with raw. Frying considerably altered fatty acid composition of fish muscle. It increased saturated fatty acid concentration and decreased unsaturated. Hence, frying noticeably decreases the nutritional quality of fish muscle. Therefore, it is suggested that further analysis on fatty acid composition of oil usually used for frying and the nutritional quality index across frying cycles.

Identification of characteristic compounds of moderate volatility in breast cancer cell lines.

In this study, we were challenging to identify characteristic compounds in breast cancer cell lines. GC analysis of extracts from the culture media of breast cancer cell lines (MCF-7, SK-BR-3, and YMB-1) using a solid-phase Porapak Q extraction revealed that two compounds of moderate volatility, 1-hexadecanol and 5-(Z)-dodecenoic acid, were detected with markedly higher amount than those in the medium of fibroblast cell line (KMST-6). Furthermore, LC-TOF/MS analysis of the extracts clarified that in addition to the above two fatty acids, the amounts of five unsaturated fatty acids [decenoic acid (C10:1), decadienoic acid (C10:2), 5-(Z)-dodecenoic acid (C12:1), 5-(Z)-tetradecenoic acid (C14:1), and tetradecadienoic acid (C14:2)] in MCF-7 medium were higher than those in medium of KMST-6. Interestingly, H2O2-oxidation of 5-(Z)-dodecenoic acid and 5-(Z)-tetradecenoic acid produced volatile aldehydes that were reported as specific volatiles in breath from various cancer patients, such as heptanal, octanal, nonanal, decanal, 2-(E)-nonenal, and 2-(E)-octenal. Thus, we concluded that these identified compounds over-produced in breast cancer cells in this study could serve as potential precursors producing reported cancer-specific volatiles.

Different nutrient intake and prevalence of gastrointestinal comorbidities in women with endometriosis.

Even though endometriosis presents one of the most common gynaecological diseases, the pathogenesis is insufficiently studied. Besides immunologic, inflammatory or oxidative processes, recent studies also suggest an influence of nutrition on disease onset and progression. Because data about the actual nutrient intake of endometriosis patients are scarce, we aimed to examine the actual nutrient intake and potential influencing factors in these women. A total of 156 women with endometriosis (EM) and 52 age-matched controls were included in this retrospective case-control study. All women filled in a validated food frequency questionnaire to acquire the nutrient intake of the past 12 months and a disease-related questionnaire for the determination of disease status, clinical symptoms and comorbidities. Patients with endometriosis suffered significantly more from diet-related comorbidities like food intolerances (25.6% versus 7.7%; P = 0.009) and allergies (57% versus 31%; P < 0.001) compared to controls. Also gastrointestinal symptoms, including constipation, flatulence, pyrosis, diarrhea or frequent defecation, were higher in the EM group (77% versus 29%; P < 0.001). The nutrient intake of patients with endometriosis differed significantly compared to controls with a significantly lower ingestion of organic acids (P = 0.006), maltose (P = 0.0.16), glycogen (P = 0.035), tetradecenoic acid (P = 0.041), methionine (P = 0.046), lysine (P = 0.048), threonine (P = 0.046) and histidine (P = 0.049). The total intake of animal proteins was significantly lower in the EM group compared to the controls (P = 0.047). EM patients showed a decreased intake of vitamin C (P = 0.031), vitamin B12 (P = 0.008) and magnesium (P = 0.043) compared to controls. This study confirms a high association of endometriosis and gastrointestinal disorders accompanied by an altered nutrient intake. A dietary intervention by a professional nutritionist may help to reduce disease burden in the affected women.

Diversity and antiviral potential of rhizospheric and endophytic Bacillus species and phyto-antiviral principles against tobacco streak virus in cotton

Plant growth promoting rhizobacteria arewidely exploited for the management of various fungal and bacterial diseases in plants. However, antiviral action of PGPR and their efficiency have been rarely investigated. In the present study, influential diversity of Bacillus species was related with tobacco streak virus (TSV) infection in cotton. The study revealed that, the population of B. subtilis, B. licheniformis and B. velezensis in rhizosphere of apparently healthy cotton plants were comparatively higher than TSV infected plants, indicating that they efficiently colonized the rhizosphere. Similarly, the population of the endophytic B. cereus and B. licheniformis were relatively higher in apparently healthy than TSV infected cotton plants. In vitro screening of rhizospheric, endophytic Bacillus species and phyto-antiviral principles revealed that rhizospheric B. amyloliquefaciens (VB7) and endophytic B. licheniformis (CoEH6) were effective in the suppression of TSV symptoms in indicator host (cowpea). The strain B. amyloliquefaciens (VB7) contained ten antimicrobial peptide genes responsible for the biosynthesis of antibiotics including, iturin, bacilysin, bacillomycin, surfactin, subtilin, and subtilosin. Moreover, the strain VB7 is reported to secrete pentadecenoic acid, heptadecenoic acid, octadecenoicacid, pyrrolo, piperazinedione and tetradecenoic acid, which would have together complemented in the antiviral activity. Upon simultaneous inoculation of the bacterium or phyto-antiviral principles with TSV in the indicator host plant, revealed that B. amyloliquefaciens (VB7) and M. jalapa were much effective and reduced the number of lesions up to 2.22/leaf and 3.00/leaf respectively compared with TSV inoculated control (25.28 lesions cm−2 area). Further, under field conditions, soil application and foliar spray of the B. amyloliquefaciens (VB7) resulted in 52 per cent reduction in TSV incidence. For reference TSV incidence in B. amyloliquefaciens (VB7) treated and untreated plots were 21.67 (PDI) and 45 (PDI) respectively. Moreover, B. amyloliquefaciens (VB7) improved seed cotton yield upto 149.45 g/plant compared to control (97.71 g/plant). Thus B. amyloliquefaciens (VB7) was exploited as an efficient antagonist for the management of TSV in cotton.

Unusual Lipid A from a Cold-Adapted Bacterium: Detailed Structural Characterization.

Colwellia psychrerythraea 34H is a Gram-negative cold-adapted microorganism that adopts many strategies to cope with the limitations associated with the low temperatures of its habitat. In this study, we report the complete characterization of the lipid A moiety from the lipopolysaccharide of Colwellia. Lipid A and its partially deacylated derivative were completely characterized by high-resolution mass spectrometry, NMR spectroscopy, and chemical analysis. An unusual structure with a 3-hydroxy unsaturated tetradecenoic acid as a component of the primary acylation pattern was identified. In addition, the presence of a partially acylated phosphoglycerol moiety on the secondary acylation site at the 3-position of the reducing 2-amino-2-deoxyglucopyranose unit caused tremendous natural heterogeneity in the structure of lipid A. Biological-activity assays indicated that C. psychrerythraea 34H lipid A did not show an agonistic or antagonistic effect upon testing in human macrophages.

Identification of self-growth-inhibiting compounds lauric acid and 7-(Z)-tetradecenoic acid from Helicobacter pylori.

Helicobacter pylori growth medium is usually supplemented with horse serum (HS) or FCS. However, cyclodextrin derivatives or activated charcoal can replace serum. In this study, we purified self-growth-inhibiting (SGI) compounds from H. pylori growth medium. The compounds were recovered from porous resin, Diaion HP-20, which was added to the H. pylori growth medium instead of known supplements. These SGI compounds were also identified from 2,6-di-O-methyl-β-cyclodextrin, which was supplemented in a pleuropneumonia-like organisms broth. The growth-inhibiting compounds were identified as lauric acid (LA) and 7-(Z)-tetradecenoic acid [7-(Z)-TDA]. Although several fatty acids had been identified in H. pylori, these specific compounds were not previously found in this species. However, we confirmed that these fatty acids were universally present in the cultivation medium of the H. pylori strains examined in this study. A live/dead assay carried out without HS indicated that these compounds were bacteriostatic; however, no significant growth-inhibiting effect was observed against other tested bacterial species that constituted the indigenous bacterial flora. These findings suggested that LA and 7-(Z)-TDA might play important roles in the survival of H. pylori in human stomach epithelial cells.

Plasma metabolic profiling of dairy cows affected with clinical ketosis using LC/MS technology

Background: Ketosis in dairy cattle is an important metabolic disorder. Currently, the plasma metabolic profile of ketosis as determined using liquid chromatography–mass spectrometry (LC/MS) has not been reported.Objective: To investigate plasma metabolic profiles from cows with clinical ketosis in comparison to control cows.Animals and methods: Twenty Holstein dairy cows were divided into two groups based on clinical signs and plasma β-hydroxybutyric acid and glucose concentrations 7–21 days postpartum: clinical ketosis and control cows. Plasma metabolic profiles were analyzed using LC/MS. Data were processed using principal component analysis and orthogonal partial least-squares discriminant analysis.Results: Compared to control cows, the levels of valine, glycine, glycocholic, tetradecenoic acid, and palmitoleic acid increased significantly in clinical ketosis. On the other hand, the levels of arginine, aminobutyric acid, leucine/isoleucine, tryptophan, creatinine, lysine, norcotinine, and undecanoic acid decreased markedly.Conclusion: Our results showed that the metabolic changes in cows with clinical ketosis involve complex metabolic networks and signal transduction. These results are important for future studies elucidating the pathogenesis, diagnosis, and prevention of clinical ketosis in dairy cows.

Under low irradiation, the light regime modifies growth and metabolite production in various species of microalgae

The effects of continuous light exposure (24L:0D) and a 12 h:12 h light/dark regime (12L:12D) were compared on the growth and carotenoid, protein, sugar, lipid, and fatty acid contents in Chlorella vulgaris, Nannochloropsis sp., Isochrysis galbana, and Dunaliella salina cultured in a batchwise facility. These microalgae were grown axenically under a low photon flux density (PFD) of 27 μmol photons m−2 s−1. C. vulgaris, Nannochloropsis sp., and I. galbana exhibited the highest cell densities when cultured under 24L:0D, whereas D. salina grew better under the alternating light/dark regime. I. galbana accumulated high levels of proteins, sugars, and lipids and exhibited the highest carotenoid content under 24L:0D. Protein production was enhanced in C. vulgaris under 24L:0D. The highest total lipid content was recorded for D. salina, reaching 74.6 % of total proteins, sugars, and lipids in cells at the stationary phase when grown under 12L:12D. The light/dark regime at low PFD was sufficient to stimulate the accumulation of monounsaturated and polyunsaturated fatty acids in all four algae. Their levels, like those of saturated fatty acids, did not differ significantly under the two light regimes. D. salina was an important source of tetradecenoic acid 14:1(n-5). Nannochloropsis sp. produced a large amount of the essential eicosapentaenoic acid, which reached 20 % of total fatty acids under 12L:12D, while I. galbana exhibited the highest level of docosahexaenoic acid, which reached 21 % under both light regimes. This study demonstrated the feasibility of culturing microalgae under low PFD in order to produce large quantities of valuable metabolites, especially various lipids with neutraceutical value.

Characterization of a Diffusible Signaling Factor from Xylella fastidiosa

ABSTRACTCell-cell signaling in Xylella fastidiosa has been implicated in the coordination of traits enabling colonization in plant hosts as well as insect vectors. This cell density-dependent signaling has been attributed to a diffusible signaling factor (DSF) produced by the DSF synthase RpfF. DSF produced by related bacterial species are unsaturated fatty acids, but that of X. fastidiosa was thought to be different from those of other taxa. We describe here the isolation and characterization of an X. fastidiosa DSF (XfDSF) as 2(Z)-tetradecenoic acid. This compound was isolated both from recombinant Erwinia herbicola expressing X. fastidiosa rpfF and from an X. fastidiosa rpfC deletion mutant that overproduces DSF. Since an rpfF mutant is impaired in biofilm formation and underexpresses the hemagglutinin-like protein-encoding genes hxfA and hxfB, we demonstrate that these traits can be restored by ca. 0.5 µM XfDSF but not by myristic acid, the fully saturated tetradecenoic acid. A phoA-based X. fastidiosa biosensor that assesses DSF-dependent expression of hxfA or hxfB revealed a high level of molecular specificity of DSF signaling.

Chemical contituents in leaves of Ehretia thyrsiflora

To investigate the chemical constituents of Ehretia thyrsiflora. Compounds were isolated with silica gel, Sephadex LH-20 and RP-C18 colum chromatography. Their structures were elucidated by means of physico-chemical properties and spectral analysis. Six compounds were isolated and identified as beta-sitosterol (1), ethyl caffeate (2), 2-methoxyl benzoic acid octyl ester (3), tetradecenoic acid, 2,3-dihydroxypropyl ester (4), daucoster (5), allantoin (6). Compounds 1-5 were obtained from this species for the first time. Compounds 2-5 were obtained from the genus Ehretia for the first time.

Nitro-fatty Acid Metabolome: Saturation, Desaturation, β-Oxidation, and Protein Adduction

Nitrated derivatives of fatty acids (NO2-FA) are pluripotent cell-signaling mediators that display anti-inflammatory properties. Current understanding of NO2-FA signal transduction lacks insight into how or if NO2-FA are modified or metabolized upon formation or administration in vivo. Here the disposition and metabolism of nitro-9-cis-octadecenoic (18:1-NO2) acid was investigated in plasma and liver after intravenous injection in mice. High performance liquid chromatography-tandem mass spectrometry analysis showed that no 18:1-NO2 or metabolites were detected under basal conditions, whereas administered 18:1-NO2 is rapidly adducted to plasma thiol-containing proteins and glutathione. NO2-FA are also metabolized via beta-oxidation, with high performance liquid chromatography-tandem mass spectrometry analysis of liver lipid extracts of treated mice revealing nitro-7-cis-hexadecenoic acid, nitro-5-cis-tetradecenoic acid, and nitro-3-cis-dodecenoic acid and corresponding coenzyme A derivatives of 18:1-NO2 as metabolites. Additionally, a significant proportion of 18:1-NO2 and its metabolites are converted to nitroalkane derivatives by saturation of the double bond, and to a lesser extent are desaturated to diene derivatives. There was no evidence of the formation of nitrohydroxyl or conjugated ketone derivatives in organs of interest, metabolites expected upon 18:1-NO2 hydration or nitric oxide (*NO) release. Plasma samples from treated mice had significant extents of protein-adducted 18:1-NO2 detected by exchange to added beta-mercaptoethanol. This, coupled with the observation of 18:1-NO2 release from glutathione-18:1-NO2 adducts, supports that reversible and exchangeable NO2-FA-thiol adducts occur under biological conditions. After administration of [3H]18:1-NO2, 64% of net radiolabel was recovered 90 min later in plasma (0.2%), liver (18%), kidney (2%), adipose tissue (2%), muscle (31%), urine (6%), and other tissue compartments, and may include metabolites not yet identified. In aggregate, these findings show that electrophilic FA nitroalkene derivatives (a) acquire an extended half-life by undergoing reversible and exchangeable electrophilic reactions with nucleophilic targets and (b) are metabolized predominantly via saturation of the double bond and beta-oxidation reactions that terminate at the site of acyl-chain nitration.

Leaky β-Oxidation of a trans-Fatty Acid: INCOMPLETE β-OXIDATION OF ELAIDIC ACID IS DUE TO THE ACCUMULATION OF 5-TRANS-TETRADECENOYL-CoA AND ITS HYDROLYSIS AND CONVERSION TO 5-TRANS-TETRADECENOYLCARNITINE IN THE MATRIX OF RAT MITOCHONDRIA

The degradation of elaidic acid (9-trans-octadecenoic acid), oleic acid, and stearic acid by rat mitochondria was studied to determine whether the presence of a trans double bond in place of a cis double bond or no double bond affects beta-oxidation. Rat mitochondria from liver or heart effectively degraded the coenzyme A derivatives of all three fatty acids. However, with elaidoyl-CoA as a substrate, a major metabolite accumulated in the mitochondrial matrix. This metabolite was isolated and identified as 5-trans-tetradecenoyl-CoA. In contrast, little or none of the corresponding metabolites were detected with oleoyl-CoA or stearoyl-CoA as substrates. A kinetic study of long-chain acyl-CoA dehydrogenase (LCAD) and very long-chain acyl-CoA dehydrogenase revealed that 5-trans-tetradecenoyl-CoA is a poorer substrate of LCAD than is 5-cis-tetradecenoyl-CoA, while both unsaturated acyl-CoAs are poor substrates of very long-chain acyl-CoA dehydrogenase when compared with myristoyl-CoA. Tetradecenoic acid and tetradecenoylcarnitine were detected by gas chromatography/mass spectrometry and tandem mass spectrometry, respectively, when rat liver mitochondria were incubated with elaidoyl-CoA but not when oleoyl-CoA was the substrate. These observations support the conclusion that 5-trans-tetradecenoyl-CoA accumulates in the mitochondrial matrix, because it is less efficiently dehydrogenated by LCAD than is its cis isomer and that the accumulation of this beta-oxidation intermediate facilitates its hydrolysis and conversion to 5-trans-tetradecenoylcarnitine thereby permitting a partially degraded fatty acid to escape from mitochondria. Analysis of this compromised but functional process provides insight into the operation of beta-oxidation in intact mitochondria.

Characterization of Type I and Type II Myristoyl-CoA:protein N -Myristoyltransferases with the Acyl-CoAs found on Heterogeneously Acylated Retinal Proteins

Protein myristoylation occurs when the 14 carbon fatty acid, myristic acid, is covalently attached by amide linkage to a protein's N -terminal glycine by an N -terminal myristoyltransferase (NMT). A variation of this called heterogeneous acylation occurs in vivo only in retina when specific proteins are modified by myristic acid (14:0), tetradecenoic acid (14:1 n–9), tetradecadienoic acid (14:2n –6), and lauric acid (12:0). Myristic and lauric acids are relatively rare, comprising approximately 1% of the fatty acids in the retina. The unsaturated fatty acids 14:1 n–9 and 14:2 n–6 are less abundant, but can be synthesized in retina by retroconversion of 18:1 n–9 and 18:2 n–6 fatty acids, respectively. A previous quantitative study of acyl-CoA pools in bovine retina, heart, and liver found comparable levels of acyl-CoAs in each tissue, indicating that heterogeneous acylation is not due to limiting amounts of myristoyl-CoA in retina. In this current study the authors have characterized a panel of purified recombinant Type I and II NMTs found in retina and liver by assessing their utilization of the four acyl-CoAs used in vivo to acylate retina proteins. Acceptor peptides used in these assays were derived from the N -termini of src which is only myristoylated in vivo, and the cAMP dependent kinase A catalytic subunit which is heterogeneously acylated in retina, but myristoylated in other tissues. The authors have tested the ability of unlabelled acyl-CoAs to compete with [3H] myristoyl-CoA transfer, the efficacy of an NMT inhibitory protein (NIP71), and acyl-CoA affinity chromatography was used to isolate endogenous NMT inhibitory factor(s) from bovine heart and retina tissue homogenates. These results provide a basis of kinetic parameters and enzymatic characterization for Type I and Type II NMTs with two acceptor peptides and the four physiologically relevant fatty acid-CoAs found on retinal proteins, but do not indicate that heterogeneous acylation is a specialized function of any of the enzymes tested in this study.

Moth desaturase characterized that produces both Z and E isomers of Δ11-tetradecenoic acids

The redbanded leafroller moth, Argyrotaenia velutinana (Lepidoptera: Tortricidae) uses a 92:8 mixture of (Z)-11- and ( E)-11-tetradecenyl acetate in its pheromone blend. These are produced in the abdominal pheromone gland from the corresponding acids, which are biosynthesized in the gland in a 3:2 Z/E ratio by desaturation of myristoyl CoA. The Δ11 desaturase involved in this reaction exhibits unusual substrate and stereospecificities in specifically producing Z11 and E11 isomers of tetradecenoic acid, and exhibiting no activity with C16 and C18 precursor acids. This report describes the cloning and expression of the redbanded leafroller moth Δ11 desaturase, and compares its amino-acid sequence to those of other known insect Z9, Z10, Z11, and E11 desaturases. The metabolic Z9 desaturase from fat body tissue also was cloned and expressed, and found mainly to produce Z9-16:Acid and Z9-18:Acid. The open reading frame of the Δ11 desaturase encodes a protein with 329 amino acids, whereas the open reading frame of the Z9 desaturase encodes a protein with 351 amino acids. Addition of this new Δ11 desaturase with its different substrate and regiospecificities to the databank of characterized integral-membrane desaturases will be key in efforts to determine amino-acid mutations responsible for the wide array of unsaturated fatty-acid products.

Characterization of a biosurfactant, mannosylerythritol lipid produced from Candida sp. SY16.

One yeast strain, SY16, was selected as a potential producer of a biosurfactant, and identified as a Candida species. A biosurfactant produced from Candida sp. SY16 was purified and confirmed to be a glycolipid. This glycolipid-type biosurfactant lowered the surface tension of water to 29 dyne/cm at critical micelle concentration of 10 mg/l (1.5 x 10(-5) M), and the minimum interfacial tension was 0.1 dyne/cm against kerosene. Thin-layer and high-pressure liquid chromatography studies demonstrated that the glycolipid contained mannosylerythritol as a hydrophilic moiety. The hydrophilic sugar moiety of the biosurfactant was determined to be beta-D-mannopyranosyl-(1-->4)-O-meso-erythritol by nuclear magnetic resonance (NMR) and fast atom bombardment mass-spectroscopy analyses. The hydrophobic moiety, fatty acids, of the biosurfactant was determined to be hexanoic, dodecanoic, tetradecanoic, and tetradecenoic acid by gas chromatography-mass spectroscopy. The structure of the native biosurfactant was determined to be 6-O-acetyl-2,3-di-O-alkanoyl-beta-D-mannopyranosyl-(1-->4)-O-meso- erythritol by NMR analyses. We newly determined that an acetyl group was linked to the C-6 position of the D-mannose unit in the hydrophilic sugar moiety.

Simultaneous analysis of plasma free fatty acids and their 3-hydroxy analogs in fatty acid β-oxidation disorders

We present a new derivatization procedure for the simultaneous gas chromatographic-mass spectrometric analysis of free fatty acids and 3-hydroxyfatty acids in plasma. Derivatization of target compounds involved trifluoroacetylation of hydroxyl groups and tert-butyldimethylsilylation of the carboxyl groups. This new derivatization procedure had the advantage of allowing the complete baseline separation of free fatty acids and 3-hydroxyfatty acids while the superior gas chromatographic and mass spectrometric properties of tert-butyldimethylsilyl derivatives remained unchanged, permitting a sensitive analysis of the target compounds. Thirty-nine plasma samples from control subjects and patients with known defects of mitochondrial fatty acid beta-oxidation were analyzed. A characteristic increase of long-chain 3-hydroxyfatty acids was observed for all of the long-chain 3-hydroxyacyl-CoA dehydrogenase-deficient and mitochondrial trifunctional protein-deficient plasma samples. For medium-chain acyl-CoA dehydrogenase deficiency and very-long-chain acyl-CoA dehydrogenase deficiency, decenoic and tetradecenoic acids, respectively, were the main abnormal fatty acids, whereas the multiple acyl-CoA dehydrogenase-deficient patients showed variable increases of these unusual intermediates. The results showed that this selective and sensitive method is a powerful tool in the diagnosis and monitoring of mitochondrial fatty acid beta-oxidation disorders.

Cryobacterium psychrophilum gen. nov., sp. nov., nom. rev., comb. nov., an obligately psychrophilic actinomycete to accommodate "Curtobacterium psychrophilum" Inoue and Komagata 1976.

"Curtobacterium psychrophilum," proposed by Inoue and Komagata in 1976, is a psychrophilic gram-positive irregular rod isolated from Antarctic soil. This organism grew optimally at 9 to 12 degrees C and did not grow at higher than 18 degrees C. Chemotaxonomic characteristics of this organism were the presence of 2,4-diaminobutyric acid in the cell wall and menaquinone-10 as the predominant respiratory quinone. The cellular fatty acid profile, which contained a significant amount of an anteiso-branched monounsaturated acid, 12-methyl tetradecenoic acid, was a distinctive characteristic of this organism and was reasonable for adaptation to low temperature. Phylogenetic analysis based on 16S ribosomal DNA sequences revealed that this organism was positioned at a separate branch in the family Microbacteriaceae, actinomycetes with group B peptidoglycan. We propose the name Cryobacterium psychrophilum gen. nov., sp. nov. for this organism. The type strain is JCM 1463 (= IAM 12024 = ATCC 43563 = IFO 15735 = NCIMB 2068).

Four Species of Noctuid Moths Degrade Sex Pheromone by a Common Antennal Metabolic Pathway

Z-9-tetradecenyl acetate (Z-9-14:OAc) is a component in the female sex pheromones of the cabbage looper, Trichoplusia ni (Hübner), beet armyworm, Spodoptera exigua (Hübner), fall armyworm, Spodoptera frugiperda (J. E. Smith), and black cutworm, Agrotis ipsilon (Hufnagel). We compared the in vivo catabolism of Z-9-14:OAc in time course fashion after the tritiated compound was applied topically to the antennae of males in the four species. Catabolism of tritiated European corn borer, Ostrinia nubilalis (Hübner), sex pheromone (Z-11-14:OAc) was monitored concomitantly so direct comparisons could be made between the male borer and the noctuid males. Results showed that catabolism of pheromone in all four noctuid moths proceeded along the same hydrolysis-alcohol oxidation pathway as has been observed in the European corn borer male. Catabolism was mathematically modeled with first-order differential equations as a four-compartment degradative system in which tritiated pheromonal acetate was sequentially converted to tetradecenol, tetradecenoic acid and water. The modeling revealed subtle differences in catabolism from one species to another and that most species exhibited a finite capacity to catabolize the pheromone.

Synthesis of [14,14,14- 2H 3] 12-hydroxytetradecanoic acid and [13,14- 2H 2] 11-hydroxytetradecanoic acid useful as tracers to study a (11 E)-desaturation reaction in Spodoptera littoralis

The synthesis of deuterium labeled 11- and 12-hydroxytetradecanoic acids to study a (11 E) desaturase in the moth Spodoptera littoralis is reported. [14,14,14- 2H 3] 12-hydroxytetradecanoic acid was synthesized in four steps from 11-iodo-1-undecene in 49% overall yield. Deuterium was introduced by reaction of an epoxy ester with (CD 3) 2CuLi. The preparation of [13,14- 2H 2] 11-hydroxytetradecanoic acid was carried out in six steps from 11-bromoundecanoic acid in 55% overall yield. In this case, label was introduced by deuteration of an homoallyl alcohol with D 2, using the Wilkinson catalyst. Incubation of pheromone glands with either of both acids did not lead to the formation of the labeled (11 E)-tetradecenoic acid.