<i>Trans</i> unsaturated fatty acids in bacteria

Keweloh, Heribert; Heipieper, Hermann J.

doi:10.1007/bf02522611

Cited by 200 publications

(146 citation statements)

References 78 publications

Supporting

Mentioning

143

Contrasting

Order By: Relevance

“…2) (Marchand and Rontani, 2001;Rontani et al, 2011). In contrast, abiotic oxidation of cis-vaccenic acid (a typical biomarker for Gram-negative bacteria, Sicre et al, 1988;Keweloh and Heipieper, 1996) produces 10-E, 10-Z, 11-E, 12-E, 13-E and 13-Z hydroxyacids, which were useful to estimate autoxidation and photooxidation state of bacteria ( Fig. 2; Christodoulou et al, 2010).…”

Section: Lipid Degradation Products Employed For Photooxidation Automentioning

confidence: 99%

“…The three dominant monounsaturated fatty acids appeared to be hexadec-9cis-enoic (palmitoleic), octadec9cis-enoic (oleic) and octadec-11cis-enoic (vaccenic) acids (Table 3). Palmitoleic and oleic acids have numerous possible biological origins (plants, fungi, yeasts, bacteria, animals or algae) (Harwood and Russell, 1984), while vaccenic acid is a typical biomarker for Gram-negative bacteria (Sicre et al, 1988;Keweloh and Heipieper, 1996). Small amounts of the very unusual octadec-13-enoic acid could be also detected (Table 4).…”

Section: Fatty Acids and N-alkan-1-olsmentioning

confidence: 99%

See 1 more Smart Citation

Intense photooxidative degradation of planktonic and bacterial lipids in sinking particles collected with sediment traps across the Canadian Beaufort Shelf (Arctic Ocean)

et al. 2012

View full text Add to dashboard Cite

Abstract. The lipid content of seven samples of sinking particles collected with sediment traps moored at ∼ 100 m depth in summer and fall across the Canadian Beaufort Shelf (Arctic Ocean) was investigated. Our main goal was to quantify and characterize the biotic and abiotic degradation processes that acted on sinking material during these periods. Diatoms, which dominated the phytoplanktonic assemblage in every trap sample, appeared to be remarkably sensitive to Type II (i.e. involving singlet oxygen) photodegradation processes in summer, but seemed to be relatively unaffected by biotic degradation at the same time. Hence, the relative recalcitrance of phytodetritus towards biodegradation processes during the Arctic midnight sun period was attributed to the strong photodegradation state of heterotrophic bacteria, which likely resulted from the efficient transfer of singlet oxygen from photodegraded phytoplanktonic cells to attached bacteria. In addition, the detection in trap samples of photoproducts specific to wax ester components found in herbivorous copepods demonstrated that zooplanktonic faecal material exported out of the euphotic zone in summer were affected by Type II photodegradation processes as well. By contrast, sinking particles collected during the autumn were not influenced by any light-driven stress. Further chemical analyses showed that photodegraded sinking particles contained an important amount of intact hydroperoxides, which could then induce a strong oxidative stress in underlying sediments.

show abstract

Section: Lipid Degradation Products Employed For Photooxidation Automentioning

confidence: 99%

Section: Fatty Acids and N-alkan-1-olsmentioning

confidence: 99%

Intense photooxidative degradation of planktonic and bacterial lipids in sinking particles collected with sediment traps across the Canadian Beaufort Shelf (Arctic Ocean)

et al. 2012

View full text Add to dashboard Cite

show abstract

“…In parallel, Fluorazophore-L, an azoalkane moiety has been used as a fluorescent probe for reactive radicals in membrane systems for the determination of the vit-C role as antioxidant of the lipid radicals. To evaluate the influence of urate under the same reaction conditions, DOPC vesicle suspensions were irradiated in the presence of MSH and UH 3 . Figure 3 (B) shows the dose profiles of methyl oleate disappearance in LUVs in the absence (dashed line), as well as in the presence of 60 µM of UH 3 at different pH values.…”

Section: Resultsmentioning

confidence: 99%

“…Geometric isomerism has become a topic of research involving several disciplines, such as microbiology, chemistry, biochemistry, pharmacology, nutrition, and medicine. [2][3][4][5][6] Some trans fatty acid residues found in living organisms can only be formed through an endogenous transformation of the natural occurring cis conformation, and their presence has been correlated with radical stress under physiological and pathological processes. [7][8][9] Several free radicals, including the biologically relevant thiyl radicals (RS•) 10 and nitrogen dioxide (•NO 2 ), 8 are known to isomerize double bonds.…”

Section: Introductionmentioning

confidence: 99%

Biomimetic chemistry on the protection of cis phospholipid from the thiyl radical isomerization by common antioxidants

Lykakis¹,

Ferreri²,

Chatgilialoglu³

2015

Arkivoc

View full text Add to dashboard Cite

Dedicated to Prof. Michael Orfanopoulos on the occasion of his 67th birthday and retirement, and for being a splendid teacher, scientist and friend DOI: http://dx.doi.org/10.3998/ark.5550190.p008.984 AbstractIn this paper the evaluation of cis phospholipids geometry protection from the thiyl radical isomerization in the presence of common antioxidants is studied. Thus, large unilamellar vesicles (LUVs) of glycerophospholipids containing oleate moieties were used as biomimetic model to demonstrate that hydrophilic ascorbic acid and urate, and hydrophobic all-trans retinol acetate and α-tocopherol, are able to inhibit cis-trans isomerization from the thiyl radicals that are known to react as efficient isomerizing species. The synergistic effect obtained by a mix of the hydrophilic and hydrophobic antioxidants at in vivo concentrations is also proved to exert an extraordinary protection for the integrity of cis lipid geometry.

show abstract

“…Unsaturated fatty acids, such as oleic acid, linoleic acid, and linolenic acid, are much more toxic than saturated fatty acids in bacteria (15,16). Unsaturated fatty acids disrupt the membrane structure in cells because of their distorted structures (17) and inhibit fatty acid-synthesizing enzymes (18). For surviving in unsaturated fatty acid-rich environments, as a detoxification mechanism, bacteria harboring MCRA proteins hydrate unsaturated fatty acids and convert them to hydroxy fatty acids, which are degraded in cells (10).…”

mentioning

confidence: 99%

Comparison of Biochemical Properties of the Original and Newly Identified Oleate Hydratases from Stenotrophomonas maltophilia

Kang

Seo

Shin

et al. 2017

Appl Environ Microbiol

View full text Add to dashboard Cite

Oleate hydratases (OhyAs) catalyze the conversion of unsaturated fatty acids to 10-hydroxy fatty acids, which are used as precursors of important industrial compounds, including lactones and -hydroxycarboxylic and ␣, -dicarboxylic acids. The genes encoding OhyA and a putative fatty acid hydratase in Stenotrophomonas maltophilia were identified by genomic analysis. The putative fatty acid hydratase was purified and identified as an oleate hydratase (OhyA2) based on its substrate specificity. The activity of OhyA2 as a holoenzyme was not affected by adding cofactors, whereas the activity of the original oleate hydratase (OhyA1) showed an increase. Thus, all characterized OhyAs were categorized as either OhyA1 or OhyA2 based on the activities of holoenzymes upon adding cofactors, which were determined by the type of the fourth conserved amino acid of flavin adenine dinucleotide (FAD)-binding motif. The hydration activities of S. maltophilia OhyA2 toward unsaturated fatty acids, including oleic acid, palmitoleic acid, linoleic acid, ␣-linolenic acid, and ␥-linolenic acid, were greater than those of OhyA1. Moreover, the specific activity of S. maltophilia OhyA2 toward unsaturated fatty acids, with the exception of ␥-linolenic acid, was the highest among all reported OhyAs. IMPORTANCE All characterized OhyAs were categorized as OhyA1s or OhyA2s based on the different properties of the reported and newly identified holo-OhyAs in S. maltophilia upon the addition of cofactors. OhyA2s showed higher activities toward polyunsaturated fatty acids (PUFAs), including linoleic acid, ␣-linolenic acid, and ␥-linolenic acid, than those of OhyA1s. This suggests that OhyA2s can be used more effectively to convert plant oils to 10-hydroxy fatty acids because plant oils contain not only oleic acid but also PUFAs. The hydration activity of the newly identified OhyA2 from S. maltophilia toward oleic acid was the highest among the activity levels reported so far. Therefore, this enzyme is an efficient biocatalyst for the conversion of plant oils to 10-hydroxy fatty acids, which can be further converted to important industrial materials. KEYWORDS Stenotrophomonas maltophilia, enzyme characterization, oleate hydrataseO leate hydratase (OhyA) converts unsaturated fatty acids to 10-hydroxy fatty acids, which are then converted to ␥-lactones by the yeasts Candida boidinii and Waltomyces lipofer (1, 2). ␥-Lactones are flavor compounds used in food and cosmetics (3). Multistep enzymatic reactions involving OhyA, alcohol dehydrogenase, Baeyer-Villiger monooxygenases, and esterase convert unsaturated fatty acids to -hydroxycarboxylic and ␣, -dicarboxylic acids (4), which are used in the preparation of resins, nylons, plastics, and lubricants (5). An effective OhyA is necessary for the efficient production of ␥-lactones, -hydroxycarboxylic acids, and ␣, -dicarboxylic acids.

show abstract

Trans unsaturated fatty acids in bacteria

Cited by 200 publications

References 78 publications

Intense photooxidative degradation of planktonic and bacterial lipids in sinking particles collected with sediment traps across the Canadian Beaufort Shelf (Arctic Ocean)

Intense photooxidative degradation of planktonic and bacterial lipids in sinking particles collected with sediment traps across the Canadian Beaufort Shelf (Arctic Ocean)

Biomimetic chemistry on the protection of cis phospholipid from the thiyl radical isomerization by common antioxidants

Comparison of Biochemical Properties of the Original and Newly Identified Oleate Hydratases from Stenotrophomonas maltophilia

Contact Info

Product

Resources

About