scholarly journals A radiochemical assay for glycine N-acyltransferase activity. Some properties of the enzyme in rat and rabbit

1978 ◽  
Vol 172 (2) ◽  
pp. 285-291 ◽  
Author(s):  
M O James ◽  
J R Bend
Keyword(s):  
Subcellular Location ◽  
Acyl Donor ◽  
Rabbit Lung ◽  
Acyltransferase Activity ◽  
Liver And Kidney

We have developed a sensitive radiochemical assay of glycine N-acyltransferase activity, using phenylacetyl-CoA as the acyl donor and glycine as the acceptor. This assay measures formation of the product, phenylacetylglycine, instead of disappearance of the substrate, phenylacetyl-CoA, as did earlier assays. The subcellular location and some properties of the conjugating activity were determined in liver and kidney of the rabbit and the rat. Rabbit lung and intestine were also tested for activity.

scholarly journals Rational Design for Enhanced Acyltransferase Activity in Water Catalyzed by the Pyrobaculum calidifontis VA1 Esterase

2021 ◽  
Vol 9 (8) ◽  
pp. 1790
Author(s):  
Amanda Staudt ◽  
Henrik Terholsen ◽  
Jasmin Kaur ◽  
Henrik Müller ◽  
Simon P. Godehard ◽  
...  
Keyword(s):  
Organic Solvents ◽  
Rational Design ◽  
Bulk Water ◽  
Acyl Transfer ◽  
Acyl Donor ◽  
Acyltransferase Activity ◽  
Pyrobaculum Calidifontis ◽  
Synthetic Strategy ◽  
Highly Active ◽  
Acyl Transfer Activity

Biocatalytic transesterification is commonly carried out employing lipases in anhydrous organic solvents since hydrolases usually prefer hydrolysis over acyl transfer in bulk water. However, some promiscuous acyltransferases can catalyze acylation in an aqueous solution. In this study, a rational design was performed to enhance the acyltransferase selectivity and substrate scope of the Pyrobaculum calidifontis VA1 esterase (PestE). PestE wild type and variants were applied for the acylation of monoterpene alcohols. The mutant PestE_I208A is selective for (–)-menthyl acetate (E-Value = 55). Highly active acyltransferases were designed, allowing for complete conversion of (–)-citronellol to citronellyl acetate. Additionally, carvacrol was acetylated but with lower conversions. To the best of our knowledge, this is the first example of the biocatalytic acylation of a phenolic alcohol in bulk water. In addition, a high citronellol conversion of 92% was achieved with the more environmentally friendly and inexpensive acyl donor ethyl acetate using PestE_N288F as a catalyst. PestE_N288F exhibits good acyl transfer activity in an aqueous medium and low hydrolysis activity at the same time. Thus, our study demonstrates an alternative synthetic strategy for acylation of compounds without organic solvents.

scholarly journals Metabolism of conjugated sterols in eggplant. Part 2. Phospholipid : steryl glucoside acyltransferase.

2008 ◽  
Vol 55 (1) ◽  
pp. 135-140 ◽  
Author(s):  
Anna Potocka ◽  
Jan Zimowski
Keyword(s):  
Divalent Cations ◽  
Solanum Melongena ◽  
Sodium Deoxycholate ◽  
Tween 20 ◽  
Acyl Donor ◽  
Kinetic Properties ◽  
Acyltransferase Activity ◽  
Steryl Glucoside ◽  
Membrane Bound ◽  
Triton X

A membrane-bound phospholipid : steryl glucoside acyltransferase from Solanum melongena leaves was partially purified and its specificity and molecular as well as kinetic properties were defined. Among the steryl glycosides tested (e.g. typical plant steryl glucosides, steryl galactosides and cholesteryl xyloside) the highest activity was found with cholesteryl glucoside, but some structurally related compounds such as sito- and stigmasteryl glucoside or galactoside as well as cholesteryl galactoside were also acylated, albeit at lower rates. The investigated enzyme was able to use all classes of phosphoglycerolipids (phosphatidylethanolamine, phosphatidylcholine, phosphatidylserine, phosphatidylinositol, phosphatidylglycerol) as an acyl source for biosynthesis of acylated steryl glucoside. Among them 1,2-dimirystoylphosphatidylic acid appeared to be the best acyl donor. Apart from phosphoglycerolipids, 1,2-diacylglycerols were also used as acyl donor for steryl glucoside acylation, although at a distinctly lower rate. The acyl moiety was transferred from the C-1 position of phospholipid molecule. The investigated acyltransferase activity was stimulated by 2-mercaptoethanol, Triton X-100, 1-monoacylglycerols and inhibited in the presence of divalent cations such as Ca(2+), Mn(2+), Zn(2+) or Co(2+), some lipids (MDGD, ceramide), detergents (Tween 20, 40, 60 and 80, Tyloxapol, sodium deoxycholate) and high ionic strength.

N-Methylation and quaternization of pyridine in vitro by rabbit lung, liver and kidney N-methyltransferases: an S-adenosy1-L-methioninedependent reaction

Xenobiotica ◽  
1986 ◽  
Vol 16 (7) ◽  
pp. 645-650 ◽  
Author(s):  
L. A. Damani ◽  
M. S. Shaker ◽  
P. A. Crooks ◽  
C. S. Godin ◽  
C. Nwosu
Keyword(s):  
Rabbit Lung ◽  
Liver And Kidney

scholarly journals Versatility in acyltransferase activity completes chicoric acid biosynthesis in purple coneflower

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Rao Fu ◽  
Pingyu Zhang ◽  
Ge Jin ◽  
Lianglei Wang ◽  
Shiqian Qi ◽  
...  
Keyword(s):  
Chlorogenic Acid ◽  
Bioactive Compound ◽  
Acyl Donor ◽  
Serine Carboxypeptidase ◽  
Acid Biosynthesis ◽  
Acyltransferase Activity ◽  
Acyl Acceptor ◽  
Chicoric Acid ◽  
Caftaric Acid ◽  
Purple Coneflower

AbstractPurple coneflower (Echinacea purpurea (L.) Moench) is a popular native North American herbal plant. Its major bioactive compound, chicoric acid, is reported to have various potential physiological functions, but little is known about its biosynthesis. Here, taking an activity-guided approach, we identify two cytosolic BAHD acyltransferases that form two intermediates, caftaric acid and chlorogenic acid. Surprisingly, a unique serine carboxypeptidase-like acyltransferase uses chlorogenic acid as its acyl donor and caftaric acid as its acyl acceptor to produce chicoric acid in vacuoles, which has evolved its acyl donor specificity from the better-known 1-O-β-D-glucose esters typical for this specific type of acyltransferase to chlorogenic acid. This unusual pathway seems unique to Echinacea species suggesting convergent evolution of chicoric acid biosynthesis. Using these identified acyltransferases, we have reconstituted chicoric acid biosynthesis in tobacco. Our results emphasize the flexibility of acyltransferases and their roles in the evolution of specialized metabolism in plants.

scholarly journals Perinatal development of, and effect of chemical pretreatment on, glycine N-acyltransferase activities in liver and kidney of rabbit and rat

1978 ◽  
Vol 172 (2) ◽  
pp. 293-299 ◽  
Author(s):  
M O James ◽  
J R Bend
Keyword(s):  
Zealand White Rabbit ◽  
Rabbit Kidney ◽  
Chemical Pretreatment ◽  
Sprague Dawley ◽  
Adult Rats ◽  
Acyltransferase Activity ◽  
New Zealand White Rabbit ◽  
Ontogenic Development ◽  
Liver And Kidney

The ontogenic development of glycine N-acyltransferase activity was studied in preparations of hepatic and renal mitochondria from the New Zealand White rabbit and the Sprague-Dawley rat. Preparations of hepatic mitochondria from the rat and the rabbit attain adult glycine N-acyltransferase specific activities by birth and 4 weeks of age respectively, whereas mitochondrial preparations from rabbit kidney do not attain adult activity until 4 months of age. Pretreatment of adult rats or immature rabbits with salicylic acid, benzoic acid or phenobarbital had little effect on glycine N-acyltransferase activity in vitro in liver or kidney.

scholarly journals Pseudo-enzymatic S-acylation of a myristoylated Yes protein tyrosine kinase peptide in vitro may reflect non-enzymatic S-acylation in vivo

1998 ◽  
Vol 330 (2) ◽  
pp. 723-731 ◽  
Author(s):  
M. Carmen BAÑÓ ◽  
S. Caroline JACKSON ◽  
I. Anthony MAGEE
Keyword(s):  
Tyrosine Kinase ◽  
Protein Function ◽  
Protein Tyrosine Kinase ◽  
Covalent Attachment ◽  
Acyl Donor ◽  
Acyltransferase Activity ◽  
Protein Tyrosine ◽  
Cell Fractions

Covalent attachment of a variety of lipid groups to proteins is now recognized as a major group of post-translational modifications. S-acylation of proteins at cysteine residues is the only modification considered dynamic and thus has the potential for regulating protein function and/or localization. The activities that catalyse reversible S-acylation have not been well characterized and it is not clear whether both the acylation and the deacylation steps are regulated, since in principle it would be sufficient to control only one of them. Both apparently enzymatic and non-enzymatic S-acylation of proteins have previously been reported. Here we show that a synthetic myristoylated c-Yes protein tyrosine kinase undecapeptide undergoes spontaneous S-acylation in vitro when using a long chain acyl-CoA as acyl donor in the absence of any protein. The S-acylation was dependent on myristoylation of the substrate, the length of the incubation period, temperature and substrate concentration. When COS cell fractions were added to the S-acylation reaction no additional peptide:S-acyltransferase activity was detected. These results are consistent with the possibility that membrane-associated proteins may undergo S-acylation in vivo by non-enzymatic transfer of acyl groups from acyl-CoA. In this case, the S-acylation-deacylation process could be controlled by a regulated depalmitoylation mechanism.

scholarly journals The acylation of lysophosphoradylglycerocholines in guinea-pig heart mitochondria

1987 ◽  
Vol 242 (1) ◽  
pp. 171-175 ◽  
Author(s):  
G Arthur ◽  
L L Page ◽  
C L Zaborniak ◽  
P C Choy
Keyword(s):  
Guinea Pig ◽  
Fatty Acyl ◽  
Heart Mitochondria ◽  
Acyl Donor ◽  
Mitochondrial Enzyme ◽  
Microsomal Enzymes ◽  
Guinea Pig Heart ◽  
Acyltransferase Activity ◽  
Equal Importance ◽  
Acyl Acceptors

The importance of the deacylation-reacylation pathway for attaining the desired fatty acid composition in microsomal phospholipids has been well established. It is not clear, however, whether this mechanism is of equal importance in mitochondria. The absence of acyltransferase activity in mammalian heart mitochondria has been reported in a number of studies. In the present study we report the presence of acyltransferase activities for lysophosphoradylglycerocholines in guinea-pig heart mitochondria. This enzyme showed properties that were considerably different from those of the microsomal enzymes. Of all the acyl-CoAs tested (C18:0, C18:1, C18:2 and C20:4) the mitochondrial enzyme utilized only linoleoyl-CoA as fatty acyl donor and utilized both 1-acyl-sn-glycero-3-phosphocholine and 1-alkenyl-sn-glycero-3-phosphocholine as fatty acyl acceptors. The presence of significant quantities of fatty acids other than linoleate at the C-2 position of mitochondrial acylglycerophosphocholines, coupled with the specificity of the enzyme for linoleoyl-CoA, suggest that, in addition to reacylation, other mechanisms play a significant role in producing the molecular composition of these phospholipids found in the mitochondria.

The acylation of 1-acyl sn-glycero-3-phosphorylcholine by glial and neuronal nuclei and derived neuronal unclear envelopes: a comparison of unclear and microsomal membranes

1981 ◽  
Vol 59 (10) ◽  
pp. 848-856 ◽  
Author(s):  
R. Roy Baker ◽  
Huu-Yi Chang
Keyword(s):  
Nuclear Envelope ◽  
Phospholipid Content ◽  
Acyl Donor ◽  
Nuclear Fraction ◽  
High Concentration ◽  
Distribution Profile ◽  
Acyltransferase Activity ◽  
Microsomal Membranes ◽  
Specific Activities

A neuronal nuclear fraction (N1), a glial nuclear fraction (N2) and a fraction containing microsomal membranes (P3) were isolated from homogenates of cerebral cortices of 15-day-old rabbits. A nuclear envelope fraction (E) was prepared from fraction N1. In comparison with the parent fraction N1, fraction E had a much lower yield of protein (0.077 mg/g cerebral cortex), a low specific DNA content, an eightfold higher specific phospholipid content (0.85 μmol phospholipid phosphate/mg protein) and a very similar phospholipid distribution profile. Using 100, 50, and 25 μM 1-acyl-sn-glycero-3-phosphorylcholine (labelled with [3H]palmitate) and 100 μM oleoyl CoA, the activity of acyl-CoA:1-acyl-sn-glycero-3-phosphorylcholine acyltransferase was studied in vitro. Fractions N1 and N2 had specific activities which were two to three times the specific activities shown for fraction P3. Fraction E was particularly enriched in this acylation activity and had specific activities which were 6 times those of fraction N1 and 11–19 times those of fraction P3. The existence of nuclear acyl-CoA:1-acyl-sn-glycero-3-phosphorylcholine acyltransferase activity was indicated as was a particularly high concentration of this enzyme within the nuclear envelope. In assays of lysolecithin–lysolecithin transacylase activities, fraction N2 (glial nuclei) showed the highest specific activities, being three to four times those of fractions N1 or P3. This transacylase activity (N2) was as high as 40% of the corresponding acyltransferase activity measured in this fraction using oleoyl CoA as acyl donor.

Acetaminophen: Neonatal hepatotoxicity due to late pregnancy exposure

1987 ◽  
Vol 45 ◽  
pp. 718-719
Author(s):  
G.A. Miranda ◽  
M.A. Arroyo ◽  
C.A. Lucio ◽  
M. Mongeotti ◽  
S.S. Poolsawat
Keyword(s):  
Low Dose ◽  
Fetal Liver ◽  
Late Pregnancy ◽  
Toxic Chemicals ◽  
Control Group ◽  
High Dose ◽  
Over The Counter ◽  
Liver And Kidney ◽  
Neonatal Liver ◽  
Childbearing Women

Exposure to drugs and toxic chemicals, during late pregnancy, is a common occurrence in childbearing women. Some studies have reported that more than 90% of pregnant women use at least 1 prescription; of this, 60% used more than one. Another study indicated that 80% of the consumed drugs were not prescribed, and of this figure, 95% were “over-the-counter” drugs. Acetaminophen, the safest of all over-the-counter drugs, has been reported to induce fetal liver necrosis in man and animals and to have abortifacient and embryocidal action in mice. This study examines the degree to which acetaminophen affects the neonatal liver and kidney, when a fatty diet is simultaneously fed to the mother during late pregnancy.Timed Swiss Webster female mice were gavaged during late pregnancy (days 16-19) with fat suspended acetaminophen at a high dose, HD = 84.50 mg/kg, and a low dose, LD = 42.25 mg/kg; a control group received fat alone.

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