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PubMed2000

Effect of different carbon sources on lipase production by Candida rugosa.

Different carbon sources affecting growth and lipase production in Candida rugosa were studied by using batch cultures on defined medium. Carbohydrates and acids non-related to fats did not induce lipase production. The highest yields of enzyme were obtained with lipids or fatty acids as carbon sources. Tween 80 stimulated lipase biosynthesis and secretion outside the cell. Combinations of two types of substrates, carbohydrates and fatty acids, did not improve lipase production, and in some cases, their consumption was produced in a sequential pattern. Glucose presented a repressing effect on lipase production. Moreover, glucose was found to be effective in stimulating lipase secretion by cells with a high level of cell-bound lipase activity because of their previous growth in oleic acid.

Journal Article↗
PubMed2001

Changes in the expression of uncoupling proteins and lipases in porcine adipose tissue and skeletal muscle during feed deprivation*(1).

The hormone-sensitive and lipoprotein lipases are critical determinants of the metabolic adaptation to starvation. Additionally, the uncoupling proteins have emerged with potential roles in the metabolic adaptations required by energy deficiency. The objective of this study was to evaluate the expression (mRNA abundance) of uncoupling proteins 2 and 3 and that of hormone-sensitive and lipoprotein lipase in the adipose tissue and skeletal muscle of the pig in relationship to feed deprivation. Thirty-two male castrates (87 kg +/- 5%) were assigned at random to fed and feed-deprived treatment groups. After 96 hr, the pigs were euthanized and adipose and skeletal muscle tissue obtained for total RNA extraction and nuclease protection assays. Feed deprivation increased uncoupling protein 3 mRNA abundance 103-237% (P < 0.01) in longissimus and red and white semitendinosus muscle. In contrast, the increase in uncoupling protein 3 mRNA in adipose tissue was only 23% (P < 0.06), and adipose uncoupling protein 2 mRNA was not influenced (P > 0.66) by feed deprivation. The increased abundance of uncoupling protein 2 mRNA in the longissimus muscle of feed-deprived pigs was small (22%), but significant (P < 0.04). The expression of hormone-sensitive lipase was increased 46% and 64% (P < 0.04) in adipose tissue and longissimus muscle, respectively, by feed deprivation, whereas adipose lipoprotein lipase expression was reduced (P < 0.01) to 20% of that of the fed group. Longissimus lipoprotein lipase expression in the feed-deprived group was 37% of that of the fed group (P < 0.01), and similar reductions were detected in red and white semitendinosus muscle. Overall, these findings indicate that uncoupling protein 3 expression in skeletal muscle is quite sensitive to starvation in the pig, whereas uncoupling protein 2 changes are minimal. Furthermore, we conclude that hormone-sensitive lipase is upregulated at the mRNA level with prolonged feed deprivation, whereas lipoprotein lipase is downregulated.

Journal Article↗
PubMed2003

A novel lipase from Pseudomonas fluorescens HU380: gene cloning, overproduction, renaturation-activation, two-step purification, and characterization.

The extracellular lipase gene (lipA) from Pseudomonas fluorescens HU380 was cloned from a genomic library constructed in pBluescript SK+. Nucleotide sequence analysis revealed an open reading frame of 1854 by encoding the lipase. Its deduced amino acid sequence included internal amino acid sequences of the lipase from this strain: The lipase showed significant sequence similarity to lipases of Serratia marcescens strains and P. fluorescens strains. In Escherichia coli, lipA was expressed in the form of inclusion bodies, which were subsequently solubilized by urea followed by dialysis. The refolded protein was soluble and biologically active. The lipase purified from the E. coli transformant by this denaturation-renaturation procedure followed by only two steps of column chromatographs exhibited the same electrophoretic mobility as did the enzyme purified from P. fluorescens HU380, and both enzymes were quite similar in physicochemical properties such as specific activity, suggesting that the recombinant lipase protein has an intrinsic folding capability in vitro. The function of its C-terminal region is also discussed.

Journal Article↗
PubMedDate not supplied

Computational approach to solvent-free synthesis of ethyl oleate using Candida rugosa and Candida antarctica B Lipases. I. Interfacial activation and substrate (ethanol, oleic acid) adsorption.

This paper presents the results of a MM2 study of the adsorption of oleic acid and ethanol/water in the tunnel and active-site models of lipases from Candida rugosa and Candida antarctica B. The role of an interface polar/no polar in the opening of C. rugosa lipase's lid is also addressed, discussed and analyzed at the level of the conformational changes needed to achieve the lipase open form. The adsorption of oleic acid and alcohols considering C. antarctica B, a lipase not interfacially activated, is also presented. In this case, the tunnel is shorter than in case of C. rugosa lipase. Two different pockets can be visualized at the active site-tunnel model of C. antarctica B lipase: one for the acyl group and another for the alcohol. Wrong location of alcohol and oleic acid severely hinders reaction because it hinders the H-transfer to histidine, a key step in the reaction mechanism. Right location of alcohol decreases the possibility of alcohol inhibition. In the case of C. rugosa, no restrictions for ethanol/water location are found. For that lipase, a second adsorption site for oleic acid (outside the tunnel) is presented. This site is the exit tunnel of the ester product when oleic acid is adsorbed in the tunnel. Experimental results of our own that correlate with this study are presented.

Adsorption↗
PubMed1989

The presence and role of hormone-sensitive lipase in heart muscle.

Hormone-sensitive lipase (HSL) catalyses the initial, rate-limiting, reaction in adipose-tissue lipolysis. Hormone-stimulated lipolytic activity has also been observed in the heart, where endogenous triacylglycerol is the major energy store. However, the identity of the intracellular lipase responsible has yet to be established. We have partially purified a neutral lipase from bovine heart muscle and compared its properties with those of HSL from bovine adipose tissue. The heart lipase has the same subunit Mr as HSL, is immunoprecipitated by antiserum raised against purified HSL and is phosphorylated by cyclic AMP-dependent protein kinase, apparently at the same site as HSL (as judged by h.p.l.c. of tryptic phosphopeptides). Phosphorylation of the heart lipase was found to result in increased enzyme activity, demonstrating the lipase's potential to respond to hormonal stimuli. The heart lipase was shown to be present in myocytes by its immunoprecipitation from homogenates of rat myocytes by anti-HSL antiserum. These findings are consistent with the conclusion that HSL is responsible for intracellular lipolysis in heart.

Adipose Tissue↗
PubMedDate not supplied

Transient lipoprotein lipase deficiency with hyperchylomicronemia.

Type I hyperlipoproteinemia is a rare disorder characterized by the presence of chylomicrons in fasting plasma and dysfunction of the lipoprotein lipase system. The disease may result from primary genetic defects leading to the lack of the enzyme lipoprotein lipase or to a deficiency in the CII apoprotein activator of that enzyme. It may also appear secondary to underlying systemic diseases. We now describe a case of hyperchylomicronemia and pancreatitis with a lack of lipoprotein lipase activity as assessed by three different methods. The patient had no evidence of a plasma inactivator of lipoprotein lipase, and his plasma was able to activate the enzyme in control postheparin plasma. The postheparin plasma hepatic triglyceride lipase was normal. Tests for associated systemic diseases were negative. Six weeks after presentation, that patient's lipoprotein levels and postheparin plasma lipase activities were normal. This was a unique case of hyperchylomicronemia which for a limited time was indistinguishable from primary lipoprotein lipase deficiency by current biochemical techniques.

Child↗
PubMed2004

Characterization of an ultraviolet B-induced lipase in Arabidopsis.

An Arabidopsis expressed sequence tag clone, 221D24, encoding a lipase has been characterized using an antisense approach. The lipase gene is expressed during normal growth and development of Arabidopsis rosette leaves but is down-regulated as the leaves senesce. When plants are exposed to sublethal levels of UV-B radiation, expression of the lipase is strongly up-regulated. The lipase protein is localized in the cell cytosol and is present in all organs of Arabidopsis plants. Recombinant lipase protein produced in Escherichia coli preferentially hydrolyzed phospholipids, indicating that the gene encodes a phospholipase. Transgenic plants in which lipase expression is suppressed showed enhanced tolerance to UV-B stress but not osmotic stress and were unable to up-regulate PR-1 expression when irradiated with UV-B. The observations collectively indicate that the lipase is capable of deesterifying membrane phospholipids and is up-regulated in response to UV-B irradiation.

Amino Acid Sequence↗
PubMed1987

An Antibody to the Castor Bean Glyoxysomal Lipase (62 kD) also Binds to a 62 kD Protein in Extracts from Many Young Oilseed Plants.

An antibody raised against purified glyoxysomal lipase (triacylglycerol hydrolase EC 3.1.1.3.) from castor bean (relative molecular weight of 62,000) also binds to a protein with a relative molecular weight of 62,000 in extracts of food reserve tissues from many young oilseed plants. These plants include Brassica napus L., Zea mays L., Arachis hypogaea L., Glycine max L., Gossipium hirsutum L., Cucurbita pepo L., Helianthus annuus L., Pisum sativum L., and Cicer arietinum L. The antibody caused inhibition of triacylglycerol hydrolysis by the lipases in extracts from seedlings of corn, oilseed rape, castor bean, soybean, and peanut. The pattern of antilipase binding to the 62 kilodalton protein in subcellular fractions from these other seedlings was consistent with the patterns of lipase activity reported in the literature and it is suggested that lipases from these oil seeds all have a subunit with a molecular weight of 62,000. The protein was only found in the food reserve tissues and was not present in extracts of roots and leaves of mature plants. In addition, the immunoreactive 62 kilodalton polypeptide was not detectable in lima beans and only at very low levels in kidney beans. Both these seeds are known to contain very little storage lipid and would not be expected to contain lipase. With the exception of the acid lipase of castor bean, ungerminated seeds do not generally contain active lipases. The immunoreactive 62 kilodalton protein could not be detected in the ungerminated seeds of most plants and only at very low low levels in others.

Journal Article↗
PubMed1989

Inhibition of Neutral Lipase from Castor Bean Lipid Bodies by Coenzyme A (CoA) and Oleoyl-CoA.

The neutral lipase (EC 3.1.1.3) in lipid body membranes isolated from the endosperm of 4 day old castor (Ricinus communis L.) seedlings catalyzes the hydrolysis of [(14)C]trioleoylglycerol, releasing [(14)C]oleic acid for up to 4 hours. However, the addition of Mg-ATP and coenzyme A (CoA), which are present in the cytoplasm of plant cells, caused a progressive inhibition of the neutral lipase such that after 15 minutes, release of [(14)C]oleic acid was almost undetectable. A fatty acyl CoA synthetase was found in the lipid body membrane which converts [(14)C]oleic acid produced from the lipase reaction to [(14)C]oleoyl-CoA under these conditions. The concentration of free oleoyl-CoA in the reaction mixture when the lipase was inhibited by 50% was calculated to be about 21 micromolar. It was found that a mixture of exogenously added oleoyl-CoA and CoA was most effective in causing lipase inhibition. Little inhibition of lipase was detected in the presence of CoA alone. It is possible that this effect is important In vivo in coordinating lipase activity with fatty acid oxidation.

Journal Article↗
PubMed2004

Cyclorraphan yolk proteins and lepidopteran minor yolk proteins originate from two unrelated lipase families.

Vitellogenins, cyclorraphan yolk proteins and lepidopteran minor yolk proteins are three classes of female-specific proteins that serve as an embryonic nutritional store. Similarity to vertebrate lipid-binding proteins was established for vitellogenins and yolk proteins, vitellogenins being related to apolipoprotein B and yolk proteins to lipases. Recently, similarity between yolk proteins and minor yolk proteins was reported and it was suggested that yolk proteins are more related to minor yolk proteins than to vertebrate lipases. In this study, we cloned five additional yolk proteins from the grey fleshfly Neobellieria bullata, formerly known as Sarcophaga bullata. We used this sequence data, combined with sequence data retrieved from the NCBI protein database to evaluate the yolk protein-lipase and the yolk protein-minor yolk protein relationship. We found no similarity between yolk proteins and minor yolk proteins, but we showed that yolk proteins are related to a family of lipases containing vertebrate hepatic and pancreatic lipases while minor yolk proteins are related to a family of lipases containing vertebrate gastric and lingual lipases. The fact that three different classes of yolk storage proteins show similarity to three different classes of vertebrate lipid-binding proteins strongly suggests that this lipid-binding feature is important for insect yolk storage proteins.

Amino Acid Sequence↗
PubMed1999

Characterization and utilization of Candida rugosa lipase immobilized on controlled pore silica.

Candida rugosa lipase was immobilized by covalent binding on controlled pore silica (CPS) using glutaraldehyde as cross-linking agent under aqueous and nonaqueous conditions. The immobilized C. rugosa was more active when the coupling procedure was performed in the presence of a nonpolar solvent, hexane. Similar optima pH (7.5-8.0) was found for both free and immobilized lipase. The optimum temperature for the immobilized lipase was about 10 degrees C higher than that for the free lipase. The thermal stability of the CPS lipase was also greater than the original lipase preparation. Studies on the operational stability of CPS lipase revealed good potential for recycling under aqueous (olive-oil hydrolysis) and nonaqueous (butyl butyrate synthesis) conditions.

Journal Article↗
PubMed1999

Purification and Characterization of an Alkaline Lipase from Penicillium cyclopium PG37.

An extracellular, novel alkaline lipase produced by Penicillium cyclopium PG37 was purified by centrifugation, ammonium sulfate precipitation, and phenyl-Sepharose CL-4B, DEAE Sepharose fast flow and Sephadex G-75 column chromatographies. A 16.5-fold purification of the enzyme was achieved which had a specific activity of 5 200 u/mg protein, and the recovery of the activity was 33.2%. The purified enzyme exhibited a single band on SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and polyacrylamide gel electrophoresis (PAGE). The molecular weight of the native lipase was estimated to be about 29 kD by gel filtration using Sephadex G-150, and that of the denatured lipase was determined to be about 27.5 kD by its mobility on SDS-PAGE, indicating that the lipase was a monomer. The N-terminal amino acid sequence was determined with automatic protein sequencer to be ATADAAAFPD, which has no homology with other sequences of known lipases. The optimum temperature of the action of this enzyme was 25 degrees and the lipase was stable below 30 degrees, but only 30% of its activity remained after 20 min incubation at 40 degrees. The enzyme was stable at pH from 6.5 to 10.5, and its optimal pH for activity is 10.0. Low concentration of alkaline proteinase has little effect on the lipase PG37, therefore these two enzymes can be used as ingredients that are added to commercial detergents simultaneously.

Journal Article↗
PubMedDate not supplied

[Comparison of faecal lipase test and faecal elastase-1 test in the assessment of exocrine pancreatic function in cystic fibrosis].

OBJECTIVE: In pediatric patients, indirect tests are preferred because of their less invasive character. Among those, faecal elastase-1 test has so far been shown been shown to have the highest sensitivity and specificity. However, the role of the faecal lipase test in the diagnostic work up for pancreatic insufficiency in cystic fibrosis (CF) patients has not been defined. Therefore, the aim of the present study was to compare the sensitivity and the specificity of faecal lipase test to the faecal elastase-1 test in the assessment of exocrine pancreatic function. MATERIAL AND METHODS: 63 CF patients and 95 healthy subjects (HS) were evaluated. In all subjects, faecal elastase-1 concentration (ELISA) and lipase activity (ELISA) were measured. In 50 HS, sample-to-sample (n=3) variation from the same stool and day-to-day variation from three consecutive stools were determined twice. The presence of pancreatic insufficiency patients was documented in 55 pancreatic insufficient CF patients by the determination of faecal fat excretion and in 12 pancreatic sufficient patients by the direct test. The sensitivity and specificity of the faecal elastase-1 test and faecal lipase test were compared. RESULTS: The sample-to-sample variation (mean + SEM: 13.2+1.2% vs. 23.4+2.2%) and day-to-day variation (mean + SEM: 16.3+1.2% vs. 32.5+2.6%) were significantly lower (p<0.0001) for elastase-1 determinations than for lipase measurements. With the cut-off levels giving the same specificity for both tests (95.8%), the sensitivity of faecal elastase-1 test (87.3%) was significantly higher (p<0.04) than that of faecal lipase test (77.8%). IN CONCLUSION: Faecal lipase test is less useful in the assessment of exocrine pancreatic function sensitive than faecal elastase-1 test.

Adolescent↗
PubMed1995

The hormone-sensitive lipase (LIPE) gene located on chromosome 19q13.1-->13.2 is not duplicated on 19p13.3.

The existence of a DNA polymorphism at the hormone-sensitive lipase locus could be of great interest for genetic analysis of obesity and related disorders since hormone-sensitive lipase is the rate-limiting enzyme of adipose tissue lipolysis and therefore plays a key role in energy metabolism. The polymorphic dinucleotide repeat D19S120 was identified within a human genomic clone selected with a rat hormone-sensitive lipase cDNA. This marker was subsequently localized to the short arm of chromosome 19 (p13.3) whereas human hormone-sensitive lipase (LIPE) had been mapped to the long arm of chromosome 19 (q13.1-->13.2). A duplication of the hormone-sensitive lipase gene or the presence of a pseudogene could explain the discrepancy. Cosmids from the two regions were analyzed in Southern blot experiments. A human adipose tissue hormone-sensitive lipase full-length cDNA probe hybridized only to cosmids from the 19q13.1-->13.2 region whereas the D19S120 amplicon probe hybridized only to cosmids from the p13.3 region. These data show that the occurrence of gene duplication or the presence of a pseudogene on the short arm of chromosome 19 is very unlikely and that D19S120 is unrelated to the hormone-sensitive lipase gene.

Adipose Tissue↗
PubMed1977

Hepatic triglyceride lipase deficiency in liver disease.

The activity of post-heparin lipases in patients with alcoholic hepatitis and viral hepatitis was evaluated. Lipoprotein lipase and hepatic triglyceride lipase were differentiated by assay under high and low salt conditions and also by separation on heparin-agarose affinity chromatography columns. The mean activity of hepatic triglyceride lipase in the sera of liver disease patients was only 21-24% of the mean of controls, but lipoprotein lipase in patients' sera was not different from normal levels. Hepatic triglyceride lipase deficiency may partially account for the accumulation of a triglyceride-rich low density lipoprotein in liver disease.

Alcoholism↗
PubMed1991

Triolein-phosphatidylcholine-cholesterol emulsions as substrates for lipoprotein and hepatic lipases.

Lipolysis of emulsified glycerol tri[9,10-3H]oleate by lipoprotein lipase purified from bovine milk (E.C.3.1.1.34) and by hepatic lipase purified from rat liver perfusate was studied as a function of the phosphatidylcholine molecular species and the cholesterol content of the emulsions. Overall, the activities of the two enzymes were similar on a molar basis. Lipoprotein lipase initial lipolysis rates also were comparable for emulsions made with egg phosphatidylcholine or with saturated (dimyristoyl, dipalmitoyl and distearoyl) phosphatidylcholines when cholesterol was low. Increasing the cholesterol content of the emulsion from 2-3 mole percent to 7-14 mole percent reduced triolein lipolysis by lipoprotein lipase in emulsions made with saturated phosphatidylcholines. Rat hepatic lipase was more sensitive to increased cholesterol in emulsions made with saturated phosphatidylcholines than was lipoprotein lipase. The ability to maintain triolein lipolysis during longer incubations differed strikingly among the emulsions and for the two enzymes. Lymph chylomicrons were better substrates for both enzymes than any of the emulsions.

Animals↗
PubMed1987

Interfacial interactions between proteins and mammalian lipases.

The effects of proteins, both endogenous and exogenous, on the activity of lipases against water soluble and water insoluble substrates have been reviewed. The enzymes considered are pancreatic and gastric lipases, and lipoprotein, bile-salt-stimulated human milk and pancreatic carboxyl ester lipases. A brief account is given of the function of each enzyme and of the physical properties of the interacting proteins, which include albumins, lysozymes, globulins and immunoglobulins, myoglobin, transferrins, alpha-lactalbumin and melittin. With few exceptions (for example, the effect of colipase on pancreatic lipase), the interaction of proteins with lipases which act at the lipid-water interface of water insoluble substrates results in deactivation of enzymic activity. It seems that the amphiphilic nature of proteins allows them to aggregate at interfaces, thereby altering the nature of the interface and decreasing accessibility of the substrate to the enzyme. This discussion gives consideration to association of the proteins with the enzyme or the interface and to whether the interactions with specific binding sites or interfacial inactivation are responsible for the observations. However, the effect of proteins on lipases acting against water soluble substrates varies from protein to protein. Activation of enzyme-activity occurs if the interacting proteins are able to act as acyl transfer agents and thus introduce another catalytic hydrolysis pathway into the reaction mechanism. Inhibition may be caused by specific interactions between the protein and the enzyme or the substrate.

Animals↗
PubMed1981

Post-heparin lipolytic activity with no hepatic triacylglycerol lipase involved in a mammalian species.

It was found that lipolytic activity in bovine post-heparin plasma differed from that of other mammalian species by the fact that intravenous heparin induced the release of lipoprotein lipase but not hepatic triacylglycerol lipase. Initially, this fact was strongly suspected when no remaining lipolytic activity could be found after whole bovine post-heparin plasma had been tested with either 1 M NaCl or antiserum against lipoprotein lipase. This was further confirmed by using heparin-Sepharose affinity chromatography when the entire lipolytic activity was eluted with 1.5 M NaCl but none with 0.4 or 0.7 M NaCl. The active fraction had lipoprotein lipase characteristics, i.e. it required serum activators to produce optimum activity and was fully inhibited by NaCl of high molarity and by anti-lipoprotein lipase antiserum. Neither the different doses of heparin nor the various times of sampling altered the results. This raises the question whether hepatic triacylglycerol lipase is absent from the bovine liver or whether this enzyme is present but cannot be released by heparin.

Animals↗