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n-decane dehydrogenation by a cell-free extract of candida rugosa. 19684387652
formation of n-decene-1 from n-decane by resting cells of candida rugosa. 19695380071
anaerobic formation of n-decyl alcohol from n-decene-1 by resting cells of candida rugosa. 19705485018
enzymatic conversion of l-decene to decyl alcohol by candida rugosa jf 101. 19715003660
the intracellular polysaccharide of candida rugosa grown on hydrocarbon. 19744421399
monosaccharide formation from hydrocarbon by candida rugosa. 19744836962
[serologic specificity of various candida membranaefaciens and candida rugosa strains].c. membranaefaciens (c. majoricensis) cbs-2875 and c. rugosa 829 strains were agglutinated strongly with 0 6,7 agglutinating serum of s. cholerae suis. on the other hand the same gave a negative result with c. membranaefaciens cbs-1952 and c. rugosa (c. rugosa v. elegans) cbs-1948. these results can be considered in way of identification of the mentioned candida types.197773126
pyometra in a mare caused by candida rugosa. 1977833040
cellular fatty acids derived from normal alkanes by candida rugosa.in an attempt to examine the specific metabolic relationship between the alkane substrates and lipid products the pattern of formation of cellular lipid, especially fatty acids, has been studied in the course of incubation of cells of c. rugosa with n-alkanes in mineral medium. c18:2, c18:1, c16:1 and c16:0 fatty acids were the major products formed, irrespective of the odd or even chain length of the alkane used as substrate. these unsaturated fatty acids reached a maximum in the stationary pha ...19807434793
synthetic hydrocarbons obtained by means of coal processing as a raw material for the microbiological industry. iii. assimilation of individual hydrocarbons from kogasin by selected yeast strains of the genus candida.the dynamics of the utilization of hydrocarbons from a synthetic mixture used as sole carbon and energy source in medium during the growth of two strains of yeast, candida scottii a-31 and candida rugosa a-7, was studied. the yeasts grew in a mineral medium with 2% of hydrocarbons, on a shaker, for 72 hours. during this time almost complete utilization of n-paraffins in the medium was observed and the biomass increments were 11.2 and 12.64 g of dry wt./l, respectively. the examined strains did n ...19816168177
comparative evaluation of the iatron serological candida check kit and the api 20c kit for identification of medically important candida species.a newly developed commercial serological test (iatron laboratories, inc., tokyo, japan) for the rapid identification of medically important species of candida was evaluated against the api 20c (analytab products, plainview, n.y.) and the standard wickerham assimilation and fermentation procedures. our results indicated that the iatron and the api 20c methods are 95% accurate since both permitted identification of 78 of 82 candida isolates, representing eight medically important species. none of ...19817016900
candida rugosa: experimental mastitis in a dairy cow.candida rugosa was isolated from the milk of 70% of the cows in a dairy herd with mastitis problems. an experimental c. rugosa infection of the udder of a healthy cow resulted in a prolonged fever and an inflammatory reaction in the mammary gland and associated lymph nodes. milk secretion in the 2 infected quarters was reduced from 8.51 to 1.51 per day. histological examination revealed alveolar destruction with interstitial fibrosis accompanied by lymphocyte and macrophage accumulation. c. rugo ...19827112338
effects of organic solvents on lipase for fat splitting.the effect of organic solvents on the stability and catalytic activity of the microbial lipase from candida rugosa for hydrolysis of triglyceride (fat splitting) has been examined. the solvents examined were 5 hydrocarbons (n-hexane, n-heptane, n-octane, iso-octane and cyclohexane) and 3 ethers (diethyl-ether, diisopropylether and di-n-butylether). the results revealed that iso-octane and cyclohexane are superior to the other solvents examined for enzymatic fat splitting in organic solvent syste ...19846527614
candida rugosa in immunocompromised infection. case reports, drug susceptibility, and review of the literature.candida rugosa was isolated from two patients. one patient had acute leukemia and developed invasive disease due to this yeast on two occasions while granulocytopenic. her infection was eventually cured after treatment with amphotericin b. in another immunocompromised patient, the yeast was isolated from the sputum in the presence of a pulmonary infiltrate, but there was no other evidence for a pathogenic role. antifungal susceptibility testing of the first patient's isolate and three environmen ...19853859361
intravenous catheter-associated fungemia due to candida rugosa.we report a case of intravenous catheter-associated fungemia caused by candida rugosa; this is the first report of such an infection in a human. multiple cultures of blood taken over a 24-h period and of the intravenous catheter tip were positive for this unusual isolate. the patient was treated with intravenous amphotericin b and made an uneventful recovery. intravenous cannulae and other intravascular devices are well recognized as potential sites of intravascular infection by a variety of mic ...19854066918
characteristics of lipase-catalyzed hydrolysis of olive oil in aot-isooctane reversed micelles.candida rugosa lipase solubilized in organic solvents in the presence of both surfactant and water could catalyze the hydrolysis of triglycerides, and kinetic analysis of the lipase-catalyzed reaction was found to be possible in this system. among eight organic solvents tested, isooctane was most effective for the hydrolysis of olive oil in reversed micelles. temperature effect, ph profile, k(m,app) and v(max,app) were determined. among various chemical compounds, cu(2+), hg(2+), and fe(3+) inhi ...198618555453
the hydrolysis of triglycerides by immobilized lipase in a hydrophilic membrane reactor.in the present article a method is described to immobilize lipase from candida rugosa on a hollow fiber membrane, and the use of such a system for the hydrolysis of lipids is reported. the membranes were enka hydrophilic cuprophan-type hollow fibers, having a large specific surface area. the immobilized lipase exhibited a high stability: the half-life time was 43 days at a temperature of 30 degrees c. furthermore, it is proved that kinetic studies can be carried out with this system, operated in ...198818587749
immobilization/stabilization of lipase from candida rugosa.with the aim of fixing the enzyme to the matrix by multiple covalent linkages, lipase from candida rugosa (formerly cylindracea) has been insolubilized through its amino groups on sepharose 6b previously activated with 2,3-epoxy-1-propanol. two main variables that are known to control the number of bonds formed have been tested: the contact time between enzyme and activated support, and the temperature at which the immobilization reaction is carried out. studies on activity and stability of the ...19883228295
synthesis and antimicrobial activity of some pyrrole derivatives. iii--2-(4-arylpiperazino)-3-ethoxycarbonyl-5-aryl-pyrrole derivatives.the synthesis of 3-ethoxycarbonyl-5-aryl-pyrrole derivatives with an arylpiperazine group in position 2 is described. the in vitro biological investigation showed that compound (xviii) had considerable antibacterial activity against gram-positive microorganisms and antifungal activity against candida rugosa, while the other compounds did not show any significative activity.19883248594
characteristics of immobilized lipase-catalyzed hydrolysis of olive oil of high concentration in reverse phase system.candida rugosa lipase immobilized by adsorption on swollen sephadex lh-20 could almost completely hydrolyze 60% (v/v) olive oil in isooctane. kinetic analysis of the lipase-catalyzed hydrolysis reaction was found to be possible in this system. amount of fatty acids produced was linearly proportional to the enzyme concentration of 720 microg/g wet gel. the specific enzyme activity was 217 units/mg protein at 60% (v/v) olive oil concentration. when the initial rate is plotted versus concentration ...198918587887
kinetics, mechanism, and time course analysis of lipase-catalyzed hydrolysis of high concentration olive oil in aot-isooctane reversed micelles.candida rugosa lipase has been used to investigate the hydrolysis of high concentration olive oil in the aot-isooctane reversed micellar system at w(o) = 10, ph 7.1, and 37 degrees c. results from this work show the hydrolytic reaction obeys michaelis-menten kinetics up to the initial substrate concentration of 1.37m, with turnover number k(cat) and michaelis constant k(m) of 67.1 mumol/min mg enzyme and 0.717m, respectively. a competitive inhibition by the main product, oleic acid, has been fou ...199118600751
a study on the catalytic performance of lipase in reverse micelles.the hydrolysis of olive oil catalyzed by candida rugosa lipase solubilized in "h2o/aot/isooctane" reverse micellar solution has been studied. the optimal conditions observed for lipase in reverse micelles were t = 25 degrees c, ph = 7.9, and r = [h2o]/[aot] = 10. lipase in reverse micelles is found to be quite stable. for example, after being incubated at 33 degrees c for 12 hours in aot/isooctane with r = 5.4, the residual activity of lipase remains as high as 89%. no inhibition was observed ev ...19911824243
modulation of lipase hydrolysis and synthesis reactions using carbohydrates.a novel method for modulation of lipase hydrolysis and synthesis lipase was investigated by using carbohydrates in the microenvironment of the candida rugosa enzyme. the influence of the addition of different sugars to the previously dialysed enzyme was tested on the two reactions. rates of hydrolysis were lowered by using dialysed enzyme but were increased after sugar addition, regardless of the identity of the added sugar. in contrast, synthesis reaction rates depended on the nature of the car ...19911859825
activities of candida rugosa lipase and other esterolytic enzymes coated on glass beads and suspended in substrate and water vapor: enzymes in thin liquid films.candida rugosa lipase was enzymatically active when coated on glass beads and exposed to mixtures of substrate and water vapor over a range of relative humidities up to 100%. evidence was obtained for operation of the enzyme in a thin liquid film of concentrated buffer on the surface of the glass beads. formation of the thin film was associated with hygroscopicity of the buffer used to suspend the enzyme in preparation of the enzyme-coated beads. at some buffer concentrations estimated to be on ...19911367174
lipases from different sources vary widely in dependence of catalytic activity on water activity.we have measured the rates of esterification in hexane catalysed by suspended immobilised lipases (triacylglycerol acylhydrolase, ec 3.1.1.3), with pre-equilibration to known thermodynamic water activity (a(w)). there were important differences between the enzymes from five different microbes in their retention of activity at low a(w). that from rhizomucor miehei showed over 40% maximal activity at an a(w) of 0.12, and that from rhizopus niveus was also fairly active at low a(w). lipases from ot ...19921643087
continuous hydrolysis of olive oil by immobilized lipase in organic solvent.lipase (ec 3.1.1.3) from candida rugosa was immobilized with deae-sephadex a50, sephadex g50, sephadex lh-20, amberlite ira94, and amberlite xad-7. the enzyme immobilized with deae-sephadex a50 was found to be most effective for continuous hydrolysis of olive oil in isooctane. for the continuous reaction, 0.2 g of dry immobilized enzyme was swollen with predetermined amount of water, and packed in a glass column reactor. when the organic solvent (isooctane) containing olive oil substrate was co- ...199218601176
modeling lipolysis in a reversed micellar system: part i. conventional batch reactor.triglyceride hydrolysis using chromobacterium viscosum lipase b in a reversed micellar media was investigated in a batch-type reactor. the dynamic evolution of the product concentration was analyzed using several mechanistic models, both from the literature and developed in this work. a kinetic model with nonlinear product inhibition was found to be the most adequate for the description of batch hydrolysis data over an extensive range of time and substrate concentration. the obtained rate equati ...199318613109
lipase immobilized on hydrophobic porous polymer supports prepared by concentrated emulsion polymerization and their activity in the hydrolysis of triacylglycerides.microporous polymer supports for the immobilization of lipase have been prepared by the polymerization of a concentrated emulsion precursor. the concentrated emulsion consists of a mixture of styrene and divinyl-benzene containing a suitable surfactant and an initiator as the continuous phase and water as the dispersed phase. the volume fraction of the latter phase was greater than 0.74, which is the volume fraction of the dispersed phase for the most compact arrangement of spheres of equal radi ...199318613129
spectroscopic and kinetic studies of lipases solubilized in reverse micelles.the conformation and activity of three different lipases have been studied in reverse micelles formed by sodium bis(2-ethylhexyl) sulfosuccinate (aot) in isooctane. in the case of human pancreatic lipase, the conformation of the polypeptide chain--as judged from far-uv circular dichroism measurements--is only slightly altered after the enzyme is transferred from a bulk aqueous solution into the microenvironment of reverse micelles. significant spectral changes in the near-uv circular dichroism a ...19937682440
immobilization of candida rugosa lipase and some properties of the immobilized enzyme.lipase (triacylglycerol ester hydrolase, e.c.3.1.1.3) from candida rugosa has been immobilized on commercially available microporous polypropylene. the enzyme was rapidly adsorbed on the support, and more than 60% of the soluble activity disappeared from the medium after 1 min of incubation at room temperature. a recovery of immobilized activity of 21% was obtained when the wet preparation was immediately assayed with olive oil at the end of the immobilization protocol. the activity of the immob ...19937763462
preparation of porous polyurethane particles and their use in enzyme immobilization.porous polyurethane particles were prepared as follows: (1) two low molecular weight polymers, namely, poly[methylene(polyphenyl isocyanate)] and poly(propylene glycol) were mixed with stirring at room temperature and allowed to react. (2) the reacted mixture was dispersed with stirring in mineral oil containing small amounts of water, the catalyst dibutyltin dilaurate, and caco3 powder. in the presence of the catalyst, the reaction between the two polymers proceeded to completion. small particl ...19937764355
candida rugosa central venous catheter infection in a child. 19938265293
enantioselective lipase-catalyzed ester hydrolysis: effects on rates and enantioselectivity from a variation of the ester structure.in order to make a preliminary study of substituent effects on the rate and enantioselectivity obtained in esterolytic reactions catalyzed by a lipase from candida rugosa, a series of racemic esters, derived from some alpha-alkyl and alpha-halo phenylacetic acids, were prepared. the reactions were studied at ph 6.0 and 50 degrees c under which conditions uncatalyzed hydrolysis was relatively slow. reaction samples were studied at different points of time by means of analytical chiral reversed-ph ...19938338725
influence of the reaction medium on enzyme activity in bio-organic synthesis: behaviour of lipase from candida rugosa in the presence of polar additives.lipase from candida rugosa immobilized on celite was employed as the biocatalyst in order to examine the effect of the reaction medium upon enzymic activity and selectivity. as the model reaction, transesterification between tributyrin and pentan-2-ol in iso-octane (2,2,4-trimethylpentane) was chosen. a small amount of water (0.05%, v/v) was added to the reaction medium. enhanced transesterification yields and increased selectivity of the lipase could be obtained by manipulating the microenviron ...19938484905
insights into interfacial activation from an open structure of candida rugosa lipase.the structure of the candida rugosa lipase determined at 2.06-a resolution reveals a conformation with a solvent-accessible active site. comparison with the crystal structure of the homologous lipase from geotrichum candidum, in which the active site is covered by surface loops and is inaccessible from the solvent, shows that the largest structural differences occur in the vicinity of the active site. three loops in this region differ significantly in conformation, and the interfacial activation ...19938509417
immobilization of hydrophobic lipase derivatives on to organic polymer beads.a simple and effective method of lipase immobilization is described. lipase from candida rugosa was first modified with several hydrophobic modifiers before being adsorbed on to organic polymer beads. the soluble hydrophobic lipase derivatives adsorbed more strongly on to the various polymers as compared with the native lipase. the optimal adsorption temperature of the native and modified lipases on all the polymers was 40 degrees c. the optimal ph of adsorption was between 6 and 7. lipase immob ...19947764496
pancreatic carboxylester lipase from atlantic salmon (salmo salar). cdna sequence and computer-assisted modelling of tertiary structure.we report the isolation and characterization of a 1795-bp cdna fragment encoding atlantic salmon pancreatic carboxylester lipase from salmon pancreas mrna. the nearly full-length cdna contained a 540-amino-acid open-reading frame, encompassing the mature protein (by similarity to mammalian carboxylester lipase enzymes). the salmon carboxylester lipase primary structure shared 58% identity with mammalian carboxylester lipases, lacking the proline-rich c-terminal repeats found in human and rat car ...19948001575
relationship between water activity and catalytic activity of lipases in organic media. effects of supports, loading and enzyme preparation.the rates of synthesis of dodecyl decanoate in hexane have been measured as a function of water activity (aw), for various immobilised preparations of the lipases from rhizomucor miehei and candida rugosa. only very large changes in the amount of enzyme adsorbed to the support affect the shape of the rate/aw profile; at the highest loadings the profiles tend to become somewhat flatter. a similar levelling can be obtained by pre-adsorbing an inert protein. the effect is probably due to adjacent p ...19948020484
variability within the candida rugosa lipases family.several fungi secrete lipase isozymes differing in biochemical properties and in some cases in substrate specificity. in the yeast candida rugosa, a family of related genes encodes for multiple lipase proteins, highly homologous in sequence but partially different in the regions interacting with the substrate molecule. analysis of these substitutions performed on the basis of multiple alignments and using a 3-d model of the enzyme, allows identification of a restricted number of amino acids poss ...19948029208
comparison of updated vitek yeast biochemical card and api 20c yeast identification systems.the updated vitek yeast biochemical card (ybc) was compared with the api 20c by using 409 germ tube-negative yeasts and geotrichum spp. that were either clinical or proficiency sample isolates. the api 20c was the reference standard. the 409 isolates represented nine genera and 21 species. morphology agars were inoculated and interpreted for each isolate. the api 20c identified 406 isolates (99.3%), while the vitek ybc identified 367 (89.7%). both systems identified the majority of yeasts after ...19948051243
fungemia and colonization with nystatin-resistant candida rugosa in a burn unit.yeast isolates from burned patients were analyzed retrospectively for a 7-year period (1984-1991). topical nystatin was used routinely in the burn wound dressing as antifungal therapy beginning in july 1986. nystatin used was associated with a significant decrease in overall yeast acquisitions in burn wounds; yeasts were isolated from 15.5% of admitted patients before the use of nystatin vs. 10.5% with use of nystatin (odds ratio [or] = 0.64; 95% confidence interval [ci], 0.48-0.86). new acquisi ...19948054438
mycotic and algal bovine mastitis in denmark.a one-year examination of mammary secretions (n = 2,896) from danish cattle with clinical or subclinical mastitis revealed 45 strains of fungi and algae. the strains originated from 44 mammary secretions of 42 cows in 40 herds. the following species of fungi were identified: candida catenulata (n = 2), candida kefyr (n = 6), candida krusei (n = 17), candida rugosa (n = 6), candida tropicalis (n = 3), candida valida (n = 1), geotrichum capitatum (n = 5). the algal species prototheca zopfii was de ...19948068305
analogs of reaction intermediates identify a unique substrate binding site in candida rugosa lipase.the structures of candida rugosa lipase-inhibitor complexes demonstrate that the scissile fatty acyl chain is bound in a narrow, hydrophobic tunnel which is unique among lipases studied to date. modeling of triglyceride binding suggests that the bound lipid must adopt a "tuning fork" conformation. the complexes, analogs of tetrahedral intermediates of the acylation and deacylation steps of the reaction pathway, localize the components of the oxyanion hole and define the stereochemistry of ester ...19948142346
two conformational states of candida rugosa lipase.the structure of candida rugosa lipase in a new crystal form has been determined and refined at 2.1 a resolution. the lipase molecule was found in an inactive conformation, with the active site shielded from the solvent by a part of the polypeptide chain-the flap. comparison of this structure with the previously determined "open" form of this lipase, in which the active site is accessible to the solvent and presumably the substrate, shows that the transition between these 2 states requires only ...19948142901
contribution to the study of the alteration of lipase activity of candida rugosa by ions and buffers.a semipurified c. rugosa lipase (ls) has been prepared from commercial lipase (lc) using an economical procedure. the presence of sugars and glycopeptides has been detected in ls and lc. pure lipase only has covalently bonded sugars. the hydrolysis of olive oil catalyzed by ls and commercial lipase (lc) is sensitive to the presence of cations na(i), mg(ii), ca(ii), and ba(ii) and to the nature of buffer. highest enzyme activity is obtained with 0.1m tris/hcl buffers and the combination of nacl 0 ...19948198404
computer modeling of substrate binding to lipases from rhizomucor miehei, humicola lanuginosa, and candida rugosa.the substrate-binding sites of the triacyl glyceride lipases from rhizomucor miehei, humicola lanuginosa, and candida rugosa were studied by means of computer modeling methods. the space around the active site was mapped by different probes. these calculations suggested 2 separate regions within the binding site. one region showed high affinity for aliphatic groups, whereas the other region was hydrophilic. the aliphatic site should be a binding cavity for fatty acid chains. water molecules are ...19947833809
surfactant-induced breakthrough effects during the operation of two-phase biocatalytic membrane reactors.surface-active components, both reactants and products, are frequently encountered in two-phase, aqueous-organic, biocatalytic reactions, when such reaction are carried out in a membrane reactor, employing a membrane selectively wetted by one of the two reactants, changes in the content of these surfactants--as a consequence of the progress of the reaction--can lead to wetting transitions at the two membrane-liquid interfaces as a result of adsorption of the tenside. this can lead to a decrease ...199418618837
effects of sorbitol addition on the action of free and immobilized hydrolytic enzymes in organic media.the effect of the addition of sorbitol on the activity and stability of enzymes was examined by monitoring transesterification reactions performed in organic media at various water activities (a(w) = 0.08 to 0.97). lipases from chromobacterium viscosum and candida rugosa immobilized on celite, and chymotrypsin, free or immobilized on celite, were used. when the sorbitol-containing enzymes were employed, higher reaction rates and less hydrolysis were observed. immobilization of chymotrypsin resul ...199518623233
a comparison of lipase-catalyzed ester hydrolysis in reverse micelles, organic solvents, and biphasic systems.the performance of lipases from candida rugosa and wheat germ have been investigated in three reaction media using three acetate hydrolyses as model reactions (ethyl acetate, allyl acetate, and prenyl acetate). the effect of substrate properties and water content were studied for each system (organic solvent, biphasic system, and reverse micelles). not unexpectedly, the effect of water content is distinct for each system, and the optimal water content for enzyme activity is not always the same a ...199518623367
structured modeling and state estimation in a fermentation process: lipase production by candida rugosa.a simple structured mathematical model coupled with a methodology of state and parameter estimation is developed for lipase production by candida rugosa in batch fermentation. the model describes the system according to the following qualitative observations and hypothesis: lipase production is induced by extracellular oleic acid present in the medium. the acid is transported into the cell where it is consumed, transformed, and stored. lipase is excreted to the medium where it is distributed bet ...199518623525
stereoselectivity of microbial lipases. the substitution at position sn-2 of triacylglycerol analogs influences the stereoselectivity of different microbial lipases.in the present study, the stereoselectivity of purified lipases from candida rugosa, chromobacterium viscosum, pseudomonas species and rhizopus arrhizus towards triacylglycerols in comparison to various structural analogs were investigated. different triacylglycerol analogs with distinct polarities at position sn-2 of the glycerol backbone (1,3-diacyl-2-x-glycerol, where 2-x = 2-acyloxy, 2-alkyloxy, 2-deoxy-2-alkyl, or 2-deoxy-2-phenyl) were synthesized. substrate hydrophobicity and steric requi ...19957851405
influence of the hydrophobicity of lipase isoenzymes from candida rugosa on its hydrolytic activity in reverse micelles.two isoenzymes of candida rugosa lipase, having the same mol.wt., size and similar aminoacid sequence, were studied in reverse micelles of aot. the results demonstrated the relevance of lipase hydrophobicity in reactions in anionic micelles. this is a key factor in mitigating the inhibition effect of charged micelles. the more hydrophobic isolipase a was a better biocatalyst for hydrolytic processes in these systems. its alpha-helix content increased from 31% to 49% of the total structure in rev ...19957875331
stability studies and effect of the initial oleic acid concentration on lipase production by candida rugosa.the production of lipase by candida rugosa in batch cultures was studied. the initial concentration of the carbon source employed, oleic acid, had an important effect on the final lipolytic activity levels. the maximum lipase/substrate yield and specific productivity obtained correspond to an initial oleic acid concentration of 2 g/l. at higher concentrations, up to 8 g/l oleic acid, specific productivity decreased. lipase production was not observed below 1 g/l oleic acid. lipase inactivation i ...19957766134
structure of uncomplexed and linoleate-bound candida cylindracea cholesterol esterase.candida cylindracea cholesterol esterase (ce) reversibly hydrolyzes cholesteryl linoleate and oleate. ce belongs to the same alpha/beta hydrolase superfamily as triacylglycerol acyl hydrolases and cholinesterases. other members of the family that have been studied by x-ray crystallography include torpedo californica acetylcholinesterase, geotrichum candidum lipase and candida rugosa lipase. ce is homologous to c. rugosa lipase 1, a triacylglycerol acyl hydrolase, with which it shares 89% sequenc ...19957788294
comparative kinetic study of lipases a and b from candida rugosa in the hydrolysis of lipid p-nitrophenyl esters in mixed micelles with triton x-100.(1) lipases a and b from candida rugosa catalyzing the hydrolysis of esters in micellar media have been characterized kinetically by studies on substrate specificity, rate equation forms and modeling of enzyme mechanisms. (2) the study on specificity revealed that both lipases are non-specific esterases with similar activity against lipid p-nitrophenyl esters micellized with triton x-100. the slight difference was that lipase a has its maximum activity centered in the caprylate while that of lip ...19957827103
immobilization of lipases on polyethylene and application to perilla oil hydrolysis for production of alpha-linolenic acid.the conditions of immobilization of lipase on the polyethylene powder were examined and the immobilized lipase was used for effective production of alpha-linolenic acid from perilla oil hydrolysis. using the polyethylene powder containing micropores in its structure enabled immobilization of lipases. ethanol pretreatment increased the immobilization efficiency. the efficiency of immobilization of six different lipases was 67-91%. on hydrolysis of perilla oil, the activity of the immobilized lipa ...19957472675
structural determinants defining common stereoselectivity of lipases toward secondary alcohols.in this review we summarize some aspects of the enantiopreference of the lipase from candida rugosa following structural analysis of complexes of this lipase with two enantiomers of an analog of a tetrahedral intermediate in the hydrolysis of simple esters. the analysis of the molecular basis of the enantiomeric differentiation suggests that these results can be generalized to a large class of lipases and esterases. we also summarize our experiments on identification of the key regions in the li ...19957606666
inversion of lipase stereospecificity for fluorogenic alkyldiacyl glycerols. effect of substrate solubilization.we synthesized enantiomeric 1-o-alkyl-2,3-diacyl-sn-glycerol and 3-o-alkyl-1,2-diacyl-sn-glycerol containing pyrene as a fluorescent reporter and the trinitrophenylamino residue as a fluorescence quencher; both reporter groups were covalently bound to the omega end of the acyl chains at positions sn-2 and sn-3(1), respectively. the fluorescence of the intact substrate molecules was very low. chemical or enzymic release of the fatty acyl chains lead to fluorescence dequenching. the rate of lipoly ...19957628484
localization of lipase genes on candida rugosa chromosomes.in the yeast candida rugosa the lipase isozymes are encoded by a family of genes, five of which have been cloned and sequenced in our laboratory. in this paper we report on the identification and preliminary characterization of two new related sequences, thus extending this multigene family to seven members. the total dna content of candida cells was estimated by laser flow-cytometry at about 20 mb. eight chromosomes with sizes ranging between 100 kb and 2.1 mb, as determined by comparison with ...19958575019
intravenous catheter-related candida rugosa fungaemia. 19968693562
evaluation of pulsed-field gel electrophoresis as a typing system for candida rugosa: comparison of karyotype and restriction fragment length polymorphisms.nosocomial infections with candida species have emerged as an increasingly important cause of morbidity and mortality in intensive care units. ten candida rugosa isolates from a previously documented cluster of c. rugosa infections in one hospital (nine burn unit isolates and one isolate from another hospital ward) and eight c. rugosa isolates recovered in a referral fungus testing laboratory (comparison isolates) from distinct geographic areas were investigated by molecular techniques. isolates ...19968735104
probing the substrate specificity for lipases. a comfa approach for predicting the hydrolysis rates of 2-arylpropionic esters catalyzed by candida rugosa lipase.the enzyme catalyzed hydrolysis of esters 1-3, precursors of therapeutically important non-steroidal antiinflammatory drugs, in the presence of the lipase from candida rugosa was studied and the relative rates of the enzymatic hydrolysis were determined. with the exception of 3, which was not transformed under the reaction conditions, all transformations proved to be highly enantiospecific. usually the mechanism of enantiorecognition is probed by substrate mapping. although more theoretical appr ...19968765237
a structural basis for enantioselective inhibition of candida rugosa lipase by long-chain aliphatic alcohols.molecular modeling showed that the enantiomers of heptyl 2-methyldecanoate are productively bound to the active site of candida rugosa lipase in quite different conformations. the fast-reacting s-enantiomer may well occupy the previously identified acyl-binding tunnel in the active site of the lipase. by contrast, the slow-reacting r-enantiomer must be bound to the active site, leaving the tunnel empty to allow the formation of two catalytically essential hydrogen bonds between his 449 of the ca ...19968771199
dna fingerprinting of candida rugosa via repetitive sequence-based pcr.a repetitive sequence-based pcr (rep-pcr) technique was developed to characterize the genotypic relatedness among candida rugosa isolates. two repetitive sequences, viz., care-2 and com29 from candida albicans, were used to design primers ca-21, ca-22, and com-21, respectively. when used alone or in combination, these primers generated discriminatory fingerprints by amplifying the adjacent variable regions of the genome. twenty-three isolates from burn patients, eight from other human sources, a ...19968784568
isolation and characterization of novel long-chain acyl-coa thioesterase/carboxylesterase isoenzymes from candida rugosa.long-chain acyl-coa thioesterases, which catalyze the cleavage of acyl-coa's to free fatty acids and coash, are abundant in animal cells. however, in yeast little is known about presence and function of acyl-coa thioesterase activity. therefore a commercial lipase preparation from the yeast candida rugosa was investigated and found to contain high myristoyl-coa thioesterase activity. hydrophobic interaction chromatography separated the activity into three peaks, of which two enzymes (yte-1 and y ...19968837745
substrate specificity and kinetics of candida rugosa lipase in organic media.the fatty acid specificity of lipase from candida rugosa during the esterification of saturated fatty acids and sulcatol in toluene has been studied. the true kinetic parameters are obtained by fitting the experimental data to a ping-pong kinetic model that includes alcohol inhibition. the fitted parameter values are compared with apparent values that would be obtained from restricted data sets in which one of the substrate concentrations was kept constant. it has been found that in reactions in ...19968882001
substrate specificity and kinetics of candida rugosa lipase in organic media. 19968958093
conformational changes of different isolipases from candida rugosa in liquid interfaces and after their contact with low-water-content media. 19968958096
new class of poly(vinyl alcohol) polymers as column-chromatography stationary phases for candida rugosa lipase isoforms separation.the preparation of new stationary phases of cross-linked polyvinyl alcohol esterified with various linear fatty acids is described. the physico-chemical properties of these polymers are reported, including electron microscopy and swelling measurements. batch adsorption experiments were performed in order to characterize the basic separative properties of these phases. cross-linked polyvinyl alcohol esterified with dodecanoic acid was used for hydrophobic interaction chromatography of a commercia ...19968962504
novel method for coupling of poly(ethyleneglycol) to carboxylic acid moieties of proteins.lack of toxicity, excellent solubility and superb biocompatibility make polyethylene glycol (peg) one of the most popular modifiers of biologicals. the most common method for attachment of peg is based on modification of amino groups of proteins with methoxy- or succinimide-derivatives of peg. in the case of proteins with amino groups important for biological activity, this modification can lead to inactivation of proteins. a new strategy for covalent attachment of peg to carboxylic groups of pr ...19969174951
expedient synthesis of (r)-patulolide a.an efficient derivation of the title compound has been formulated from easily accessible 10-undecenoic acid (1). thus, dodec-11-en-2-ol (3), prepared from 1, was pyranylated and subjected to bromination with nbs followed by acetolysis to furnish (2e)-1-acetoxy-11-(tetrahydropyranyloxy)dodec-2-ene (5). its hydrolysis, oxidation, and depyranylation afforded the (2e)-hydroxy ester (9). this, on candida rugosa lipase-catalyzed acetylation, seo(2) oxidation, hydrolysis, and yamaguchi macrolactonizati ...199611667053
continuous in situ water activity control for organic phase biocatalysis in a packed bed hollow fiber reactor.packed bed hollow fiber membrane reactors were used to carry out organic phase biocatalysis at constant water activity. the performance of the device was tested by carrying out the esterification of dodecanol and decanoic acid in hexane. lipase from candida rugosa, immobilized on microporous polypropylene and packed in the shell space of the reactor, was used to catalyze the reaction. in situ water activity control was accomplished by pumping appropriate saturated salt solutions through the micr ...199618623579
immobilization of candida rugosa lipase to nylon fibers using its carbohydrate groups as the chemical link.the aim of this study was to evaluate the immobilization of lipase from candida rugosa on a nylon support by methods used to attach biomolecules to solid supports through their carbohydrate moieties. the carbohydrate groups were converted to dialdehydes by treatment with sodium periodate. the length of exposure and the periodate amount were optimized to the point where almost total activity retention was obtained. tests of the immobilized enzyme showed the expressed activity to be significantly ...199618624365
optimized enzymatic synthesis of geranyl butyrate with lipase ay from candida rugosa.response surface methodology (rsm) and five-level, five-variable central composite rotatable design (ccrd) were used to evaluate the effects of synthetic variables, such as reaction time (1-9 h), temperature (25-65 degrees c), enzyme amount (10-50%), substrate molar ratio of geraniol to tributyrin (1:0.33-1:1), and added water amount (0-20%) on molar percent yield of geranyl butyrate, using lipase ay from candida rugosa. reaction time and temperature were the most important variables and substra ...199618624369
extraordinary enantiospecificity of lipase catalysis in organic media induced by purification and catalyst engineering.a purified lipase preparation from candida rugosa was compared to its crude counterpart in anhydrous and slightly hydrated hydrophobic organic solvents. the purified lipase preparation was less active than the crude enzyme in dry n-heptane, whereas the presence of small concentrations of added water dramatically activated the purified enzyme but not the crude enzyme. thus, in the presence of as little as 0.25 microl/ml of added water in n-heptane, the purified enzyme is over 230-fold more active ...199618629896
influence of the nature of modifier in the enzymatic activity of chemical modified semipurified lipase from candida rugosa.semipurified lipase of candida rugosa (crsl) was subjected to chemical modification, and the activities of the modified lipase, in hydrolysis and esterification reactions, were examined. the esterification reactions were carried out in the absence and presence of isooctane. when the enzyme was modified with polyethylene glycol (peg), two methodologies were studied. the activation of peg with p-no(2)-phenylchloroformate gives better biocatalysts than those obtained with cyanuric chloride-peg. the ...199718636483
synthesis of lovastatin with immobilized candida rugosa lipase in organic solvents: effects of reaction conditions on initial rates.lipase from candida rugosa immobilized on a nylon support has been used to synthesize lovastatin, a drug which lowers serum cholesterol levels, by the regioselective acylation of a diol lactone precursor with 2-methylbutyric acid in mixtures of organic solvents. analogs of lovastatin having a different side chain were also obtained through this method by reacting the diol substrate with different carboxylic acids. the selection of reaction conditions that maximize the initial reaction rate is in ...199718642339
simple approach to optically active drimane sesquiterpenes based on enzymatic resolution.when the beta-acyloxy esters (+/-)-10 and (+/-)-11 were exposed to the lipase of-360 from candida rugosa or immobilized lipase of-360 in a water-saturated organic solvent, the hydrolyzed product (8as)-6 was obtained in high chemical (40%) and optical (> 99% ee) yields. the absolute structure of (8as)-6 was confirmed by the fact that (8as)-6 was converted into an authentic sample gamma-keto nitrile (8as)-17. treatment of the diol (+/-)-12 with isopropenyl acetate in the presence of the lipase god ...19979178520
influence of surface hydrophilic/hydrophobic balance on enzyme properties.two different enzyme surface modifications were carried out in order to alter the protein hydrophilic/hydrophobic balance in opposite directions and to observe the effects induced on enzyme properties. first, a novel chemoenzymatic glycosylation method was applied, which resulted in a higher enzyme surface hydrophilic character. then, an amphiphilic polymer, peg, was bound to the enzymes by chemical means, and it brought about an increase in the global hydrophobic character. two different enzyme ...19979335176
analysis of a lipase-catalyzed kinetic resolution by chiral normal-phase liquid chromatography.as part of our investigation of structure-activity relationships in a candida rugosa lipase-catalyzed ester hydrolysis reaction, methyl 2-(octylsulfinyl)benzoate has been studied, with respect to rate and enantioselectivity behaviour, using two different lipase preparations. a chiral normal-phase liquid chromatography method has been developed for determination of the experimental data, degree of conversion (c) and enantiomeric excess of the substrate (ees) or the product (eep), needed for calcu ...19979376711
cloning, sequencing, and expression of candida rugosa lipases. 19979379937
isolation of carboxylester lipase (cel) isoenzymes from candida rugosa and identification of the corresponding genes.the yeast candida rugosa produces extracellular lipases which are widely used for industrial purposes. a commercial lipase preparation from this yeast can be separated into several isoenzymes which differ in carbohydrate content, isolelectric point, substrate specificity, and primary sequence. we have here purified and characterized three lipases, which also hydrolyze p-nitrophenyl esters, from a commercial preparation of this yeast. these three carboxylester lipases (cels) elute differently on ...19979390168
molecular modeling of the structures of human and rat pancreatic cholesterol esterases.structural models have been generated for rat and human cholesterol esterases by molecular modeling. for rat cholesterol esterase, three separate models were generated according to the following procedure: (1) the cholesterol esterase sequence was aligned with those of three template enzymes: torpedo californica acetylcholinesterase, geotrichum candidum lipase and candida rugosa lipase; (2) the x-ray structure coordinates of the three template enzymes were used to construct cholesterol esterase ...19979007978
probing the substrate specificity for lipases. ii. kinetic and modeling studies on the molecular recognition of 2-arylpropionic esters by candida rugosa and rhizomucor miehei lipases.racemic arylpropionic esters 1-3, precursors of therapeutically important non-steroidal antiinflammatory drugs, were subjected to hydrolyses in the presence of either candida rugosa or rhizomucor miehei crude lipases. the hydrolyses of 1 and 2 proved to be highly enantioselective, whereas 3 was not transformed at all. both the substrate specificity and the enantioselectivity of these lipases were explained through a molecular modeling study involving docking experiments between 1-3 and the amino ...19979048908
adsorption of lipase on polypropylene powder.adsorption of different lipases by ep-100 polypropylene powder from crude and pure lipase preparations was studied. langmuir isotherms described the adsorption equilibria well both for protein and lipase activity adsorption. adsorption isotherms for five different proteins all gave a similar saturation level of 220 mg protein per g carrier. twelve commercial lipase preparations were tested for selectivity in the adsorption of lipase. for all preparations the selectivity factor was larger than on ...19979106498
design, total synthesis, and functional overexpression of the candida rugosa lip1 gene coding for a major industrial lipase.the dimorphic yeast candida rugosa has an unusual codon usage that hampers the functional expression of genes derived from this yeast in a conventional heterologous host. commercial samples of c. rugosa lipase (crl) are widely used in industry, but contain several different isoforms encoded by the lip gene family, among which the isoform encoded by the gene lip1 is the most prominent. in a first laborious attempt, the lip1 gene was systematically modified by site-directed mutagenesis to gain fun ...19989655346
characterization of the candida rugosa lipase system and overexpression of the lip1 isoenzyme in a non-conventional yeast.the fungus c. rugosa produces lipase isoenzymes (crls) homologous to the geotrichum candidum and yarrowia lipolytica lipases to which they share ca. 40 and 30% sequence identity, with a domain of sequence conservation at the n-terminal half of the protein. crl proteins have high sequence homology but are not identical in their catalytic activity, therefore calling for the resolution of isoforms via heterologous expression. the non-conventional use of a serine codon in several candida species fru ...19989720249
insights into the molecular basis for fatty acyl specificities of lipases from geotrichum candidum and candida rugosa.despite immense progress in our comprehension of lipase structure and function during the past decade, the basis for lipase acyl specificities has remained poorly understood. this review summarizes some recent advances in the understanding at the molecular-level of substrate acyl recognition by two members in a group of large (mw approximately 60 kda) microbial lipases. two aspects of acyl specificity will be focused upon. (i) the unique preference of a fungal geotrichum candidum lipase for long ...19989720250
anatomy of lipase binding sites: the scissile fatty acid binding site.shape and physico-chemical properties of the scissile fatty acid binding sites of six lipases and two serine esterases were analyzed and compared in order to understand the molecular basis of substrate specificity. all eight serine esterases and lipases have similar architecture and catalytic mechanism of ester hydrolysis, but different substrate specificities for the acyl moiety. lipases and esterases differ in the geometry of their binding sites, lipases have a large, hydrophobic scissile fatt ...19989720251
improving lipase production from candida rugosa by a biochemical engineering approach.it has been tested that the use of oleic acid as sole carbon source and as inducer of the production has an important effect in the lipase production by candida rugosa under aerobic conditions. a simple structured mathematical model coupled with a methodology to estimate biomass, specific growth rate and substrate was developed and applied to the production of candida rugosa lipase in batch, fed-batch and continuous operation to obtain a reproducible product. the best operation mode tested was a ...19989720255
physiological control on the expression and secretion of candida rugosa lipase.the fungus candida rugosa secretes an extracellular lipase whose production is induced by the addition of fatty acids to the culture broth. this lipase is indeed composed by several protein isoforms partly differing in their catalytic properties. synthesis and secretion of lipase proteins by c. rugosa cells were studied in culture media containing either glucose or oleic acid as the carbon source. it was shown that, according to their regulation, lipase-encoding genes might be grouped in two cla ...19989720256
lipase specificity toward some acetylenic and olefinic alcohols in the esterification of pentanoic and stearic acids.the esterification of five medium- and long-chain acetylenic alcohols (2-nonyn-1-ol, 10-undecyn-1-ol, 6-octadecyn-1-ol, 9-octadecyn-1-ol, and 13-docosyn-1-ol), seven olefinic alcohols (cis-3-nonen-1-ol, 10-undecen-1-ol, cis-6-octadecen-1-ol, cis-9-octadecen-1-ol, trans-9-octadecen-1-ol, trans-9, trans-11-octadecadien-1-ol, cis-9,cis-12-octadecadien-1-ol), and four short-chain unsaturated alcohols (allyl alcohol, 3-butyn-1-ol, 3-pentyn-1-ol, and cis-2-penten-1-ol) with pentanoic or stearic acid i ...19989778133
candida rugosa lipases: molecular biology and versatility in biotechnology.this review describes how the versatile candida rugosa lipases (crl) have extended the frontiers of biotechnology. as evidenced by the current literature, crl claims more applications than any other biocatalyst. this review comprises a detailed discussion on the molecular biology of crl, its versatile catalytic reactions, broad specificities and diverse immobilization strategies. it also discusses its role in the food and flavour industry, the production of ice cream and single cell protein, bio ...19989778794
enantioselective synthesis of (11e, 13s)-13-hydroxy-10-oxooctadecenoic acid, the cytotoxic principle of corn.a brief and practical enantiomeric synthesis of the title compound has been developed. the salient features of the synthesis were: (i) preparation of the required chiron, 3-octyn-1-ol via a candida rugosa lipasecatalyzed trans-acylation, (ii) use of easily accessible and inexpensive materials viz. 10-undecenoic acid and (iii) use of a simple reaction protocol.19989813891
'interfacial affinity chromatography' of lipases: separation of different fractions by selective adsorption on supports activated with hydrophobic groups.lipases contained in commercial samples of lipase extracts from rhizopus niveus (rnl) and candida rugosa (crl) have been selectively adsorbed on hydrophobic supports at very low ionic strength. under these conditions, adsorption of other proteins (including some esterases) is almost negligible. more interestingly, these lipases could be separated in several active fractions as a function of a different rate or a different intensity of adsorption on supports activated with different hydrophobic g ...19989858762
a toolbox of recombinant lipases for industrial applications.we created a toolbox of recombinant, microbial lipases, which allows us in combination with a lipase database to choose among the overexpressed lipases the most appropriate for a specific application and to improve it further via mutagenesis. by systematic comparison of geometry and properties of the scissile fatty acid binding site of five representative lipases of each family of structurally homologous lipases, three subgroups can be defined. hence, efficient expression systems for the functio ...19989928080
effect of reductive alkylation of candida rugosa lipase on its enantioselective esterification reaction. 19989928091
alcohol inhibition and specificity studies of lipase b from candida antarctica in organic solventsalcohol inhibition of the lipase b from candida antarctica has been studied through two different approaches: using the same inhibitor (1-butanol) in different organic solvents and using different inhibitors (differing in chain length) in the same solvent. the competitive inhibition constant values obtained in each case correlate with the calculated activity coefficients of the substrate, suggesting that desolvation of the alcohol is the major force changed. data dispersion observed using the se ...199810099327
enhancement of candida rugosa lipase production by using different control fed-batch operational strategies.simulation studies have predicted that maximum lipase activity is reached with fed-batch operation strategies. in this work, two different fed-batch operational strategies have been studied: constant substrate feeding rate and specific growth rate control. a constant substrate feeding rate strategy showed that maximum aqueous lipolytic activity (55 u/ml) was reached at low substrate feeding rates, whereas lipase tends to accumulate inside the cell at higher rates of substrate addition. in the se ...199810099417
optimized enzymatic synthesis of methyl benzoate in organic medium. operating conditions and impact of different factors on kineticsenzyme-catalyzed synthesis of methyl benzoate is reported. it is the first example of direct esterification of benzoic acid which provides good yields. the reaction was performed in a heterogeneous medium by candida rugosa lipase powder suspended in a hexane/toluene mixture. the impact of some factors was examined. benzoic acid does not inhibit the lipase until 100 mm. above 90 mm, methanol inhibits the enzyme. this inhibition is partially eliminated by increasing benzoic acid concentration. bel ...199810099439
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