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1.
The production of lipases by microorganisms is strongly influenced by the culture conditions. The optimum culture conditions for enzyme production are strain- and species-dependent. The aim of this study was to evaluate the impact of the carbon source used in the culture medium on the profile of lipases produced by Yarrowia lipolytica KKP 379. We observed a different pattern of extracellular and cell-bound lipase production, which was the highest in the early exponential phase. The extracellular lipase activity increased in the late exponential phase due to the lower accumulation of lipase molecules in cell walls. The best carbon source for extracellular lipase production by Y. lipolytica KKP 379 was olive oil. Glucose, dodecane and olive oil had a positive effect on biomass yield. Dodecane and/or glycerol utilization in microbiological lipase production was possible, but this process could not proceed without the addition of some activators such as olive oil in the cultivation medium.  相似文献   

2.
The production, purification and characterization of cold active lipases by Yarrowia lipolytica NCIM 3639 is described. The study presents a new finding of production of cell bound and extracellular lipase activities depending upon the substrate used for growth. The strain produced cell bound and extracellular lipase activity when grown on olive oil and Tween 80, respectively. The organism grew profusely at 20 °C and at initial pH of 5.5, producing maximum extracellular lipase. The purified lipase has a molecular mass of 400 kDa having 20 subunits forming a multimeric native protein. Further the enzyme displayed an optimum pH of 5.0 and optimum temperature of 25 °C. Peptide mass finger printing reveled that some peptides showed homologues sequence (42%) to Yarrowia lipolytica LIP8p. The studies on hydrolysis of racemic lavandulyl acetate revealed that extracellular and cell bound lipases show preference over the opposite antipodes of irregular monoterpene, lavandulyl acetate.  相似文献   

3.
Lipase biosynthesis by the fungus Rhizopus microsporus UzLT-1 was investigated. Under certain conditions the fungus could produce two forms of extracellular lipases. The paper describes the process of purification of the enzyme L-I,N- and C-terminal amino acids of the lipases have been determined. Identity of terminal amino acids of both enzymes has been demonstrated. It has been shown that both forms of lipase from Rhizopus microporus hydrolyze predominantly alpha-ester bonds.  相似文献   

4.
The procedure of isolation and purification of lipases from the fungus Oospora lactis have been developed. The existence of two different lipases has been demonstrated, one of which (Mr = 43000) is localized in the periplasmic space and can be liberated into the external medium in an unchanged form, while the other (Mr = 40000) is tightly bound to the membranes and can be solubilized by detergent treatment. The most essential properties of the lipases are discussed and a detailed analysis of the functional and physicochemical properties of extracellular lipase is given.  相似文献   

5.
The gene coding for an extracellular lipase of Bacillus licheniformis was cloned using PCR techniques. The sequence corresponding to the mature lipase was subcloned into the pET 20b(+) expression vector to construct a recombinant lipase protein containing 6 histidine residues at the C-terminal. High-level expression of the lipase by Escherichia coli cells harbouring the lipase gene-containing expression vector was observed upon induction with IPTG at 30 degrees C. A one step purification of the recombinant lipase was achieved with Ni-NTA resin. The specific activity of the purified enzyme was 130 units/mg with p-nitrophenyl-palmitate as substrate. The enzyme showed maximum activity at pH 10-11.5 and was remarkably stable at alkaline pH values up to 12. The enzyme was active toward p-nitrophenyl esters of short to long chains fatty acids but with a marked preference for esters with C(6) and C(8) acyl groups. The amino acid sequence of the lipase shows striking similarities to lipases from Bacillus subtilis and Bacillus pumilus. Based on the amino acid identity and biochemical characteristics, we propose that Bacillus lipases be classified into two distinct subfamilies of their own.  相似文献   

6.
The aim of this work is to find the best conditions to isolate lipase from a solid culture medium of Aspergillus niger NRRL3 strains using aqueous two-phase systems formed with polyethylene glycol and potassium phosphate or polyethylene glycol and sodium citrate. We studied the partitioning of a commercial lyophilizate from A. niger. Also, the lipase enzymatic activity was studied in all the phases of the systems and the results indicate that citrate anion increases lipase activity. An analysis by fluorescence spectroscopy of the interaction between lipase and the bottom and top phases of the systems shows that the protein tryptophan-environments are modified by the presence of PEG and salts. Separation of the enzyme from the rest of the proteins that make up the lyophilized was achieved with good yield and separation factor by ATPS formed by PEG 1000/Pi at pH 7, PEG 2000/Ci at pH 5.2 and PEG 4000/Ci at pH 5.2. The above mentioned systems were used in order to isolate extracellular lipase from a strain of A. niger in submerged culture and solid culture. The best system for solid culture, with high purification factor (30.50), is the PEG 4000/Ci at pH 5.2. The enzyme was produced in a solid culture medium whose production is simple and recovered in a phase poor in polymer, bottom phase. An additional advantage is that the citrate produces less pollution than the phosphate. This methodology could be used as a first step for the isolation of the extracellular lipase from A. niger.  相似文献   

7.
Extractive microbial fermentation for production of lipase by Serratia marcescens ECU1010 has been carried out in cloud point system. The cloud point system is composed of mixture nonionic surfactants with a ratio of Triton X-114 to Triton X-45 4:1 in aqueous solution. The lipase prefers to partition into the surfactant rich phase (coacervate phase) whereas the cells and other hydrophilic proteins retain in the dilute phase of cloud point system. Thus, a concentration factor 4.2-fold and a purification factor 1.3-fold of the lipase have been achieved in the extractive fermentation process. This is the first report about extractive fermentation of proteins in cloud point system.  相似文献   

8.
Geotrichum candidum CMICC 335426 was previously shown to produce two lipases termed lipase A and lipase B, lipase B being highly specific for hydrolysis of esters of cis-delta 9 fatty acids. We now describe the isolation of polyclonal antibodies specific for lipase A and lipase B. These antibodies were used in Western blotting techniques to detect the appearance of the lipases during the course of the fermentation of G. candidum CMICC 335426. A and B were found to be produced simultaneously in the extracellular medium at the start of the growth phase. The two lipases were always present at similar levels in the medium. The specific antibodies were then used to detect the presence of A- and B-like lipases in crude lipase samples from other strains of G. candidum. The lipases were found at different levels in all these samples, and the specificities of the crude lipases varied significantly from one strain to another. Differences in specificity could therefore be explained by different levels of specific (B-type) and non-specific (A-type) lipases in the medium. This was verified by purifying A- and B-type lipases from the G. candidum strain ATCC 34614.  相似文献   

9.
Cholesterol oxidase from various bacterial sources (membrane-bound and extracellular) was studied in Triton X-114R solutions above the cloud point. The influence of temperature, salt, enzyme concentration and source, and pH on phase equilibrium and enzyme partitioning was investigated in this detergent-based aqueous two-phase system. The method combines remarkable recovery (over 70% and 90% in the detergent-rich phase for the extracellular and membrane-bound forms, respectively) and 10 to 20-fold concentration of the enzyme in just one purification step. The results from cholesterol oxidase are compared with other proteins, both hydrophobic and hydrophilic. The system shows considerable promise for selectively partitioning proteins based on their surface hydrophobicity.  相似文献   

10.
Interest in lipases from microorganisms, animals, and plants has greatly increased in the past decade due to their applications in biotransformations and organic syntheses. We are reporting the purification and characterization of two lipases from the fungus, Ophiostoma piliferum, a saprophytic organism commonly found on wood. A major and a minor lipase have been co-purified by hydrophobic interaction chromatography on octyl sepharose FF, followed by ion exchange chromatography on Q sepharose FF. The lipases bound very tightly to octyl sepharose resulting in greater than 100-fold purification in this one step. The major lipase has a molecular weight of approximately 60 kDa, a pI of 3.79, and is glycosylated as determined by PAS staining. The minor lipase, which composes 10% of the total protein, has a pI of 3.6, and molecular weight of approximately 52 kDa and did not stain with the PAS reagent. Deglycosylation of the major lipase produced two proteins of lower molecular weight, a 55 kDa protein and a 52 kDa protein. The deglycosylated protein at 52 kDa co-migrates with the minor lipase on SDS-PAGE gels. N-terminal amino acid sequencing of the major and minor lipases indicated both lipases have the same N-termini and MALDI-TOF mass spectral analysis showed similar peptide patterns. Available data indicate that the lipases are derived from the same protein and appear to differ in their post-translational modification as evidenced by their pIs and molecular weight difference. The pH rate profile and thermal stability were determined for the purified O. piliferum lipase and were consistent with a mesophilic lipase. In aqueous solution, the lipases exhibited a higher rate of hydrolysis for p-nitrophenylbutyrate (C4) than for p-nitrophenylstearate (C18), which is an unexpected result.  相似文献   

11.
An isolate exhibiting high extracellular lipolytic activity was identified as Pseudomonas gessardii by 16S rDNA gene sequence analysis. The slaughterhouse waste, goat tallow, was used as a lipid substrate for the production of acidic lipase by P. gessardii. The maximum lipase activity of 156 U/ml was observed at an acidic pH of 3.5 and at 0.31 g substrate concentration. The purification steps resulted in the isolation of acidic lipase with a specific activity of 1,473 U/mg and a molecular weight of 94 kDa. One interesting feature of this purified lipase is its stability at highly acidic pH ranging from 2.0 to 5.5 with a high molecular weight. The amino acid composition was determined using HPLC. This acidic lipase has potential applications in the medicinal field as a substitute for pancreatic lipases for enzyme therapy, oleochemical and in biotechnological industries.  相似文献   

12.
Lipase (triacylglycerol acylhydrolase, EC 3.1.1.3) secreted by Pseudomonas aeruginosa PAC1R was purified from cell-free growth medium by preparative isoelectric focusing. After blotting the N-terminal amino acid sequence and the amino acid composition were determined and compared to P. fragi and P. cepacia lipases yielding significant homology between all three species. Additionally, a consensus sequence K-Y-P-i-v-l-V-H-G was identified residing at the N-terminus of Pseudomonas lipases and in the central part of Staphylococcus lipases. Treatment of lipase with the serine-specific inhibitor diethyl p-nitrophenyl phosphate caused a rapid and complete inhibition of enzyme activity indicating the presence of a serine at the catalytic site as expected from lipase consensus sequences. Upon charge-shift electrophoresis the electrophoretic mobility of purified lipase was shifted either anodally or cathodally in the presence of sodium deoxycholate and cetyltrimethylammoniumbromide, respectively. This result demonstrates that extracellular lipase of P. aeruginosa exhibits an amphiphilic character like intrinsic membrane proteins.  相似文献   

13.
A gene encoding an extracellular lipase was identified in Staphylococcus warneri 863. The deduced lipase is organised as a prepro-protein and has significant similarity to other staphylococcal lipases. The mature part of the lipase was expressed with an N-terminal histidine tag in Escherichia coli, purified and biochemically characterised. The results show that the purified lipase (named SWL2) combines the properties of the staphylococcal lipases characterised so far. It has both a high preference for short chain substrates and surprisingly, it also displays phospholipase activity. Homology alignment was used to analyse sequence-function relationships of the staphylococcal lipase family with the aim to identify the structural basis underlying the different properties of the staphylococcal lipases.  相似文献   

14.
Chitosan and its derivatives have been used as affinity matrices for purification of lipase from Aspergillus niger NCIM 1207. Trimellitic anhydride (TMA)-crosslinked deacetylated chitin adsorbed lipase selectively, yielding approximately 5-fold purification of the crude lipase with 70% yield. Further 9-fold purification occurred on eluting through Sephacryl-100. These results suggest that chitosan derivatives can be used as inexpensive biopolymer matrices for the purification of lipases for industrial applications.  相似文献   

15.
Staphylococcus warneri M exhibited extracellular lipase activity. By zymogram analysis of extracellular proteins, multiple bands were detected and the profiles changed depending on the bacterial growth phase. N-terminal amino acid sequences of three bands (N1-N3) were determined. From the genome library of S. warneri M whole DNA, the gene-directing lipase activity (named gehC(WM)) was cloned and characterized. The gehC(WM )gene encoded a protein (GehC(WM)), whose calculated molecular mass was 83.4 kDa, and the sequence was similar to the other staphylococcal lipases. Though two lipases have been known from S. warneri 863, GehC(WM) differs from both of them, indicating that this enzyme is the third extracellular lipase of the S. warneri strain. The N-terminal sequences of the N1-N3 polypeptides completely coincided with the deduced amino acid sequences in GehC(WM). GehC(WM) was predicted to be a prepro-protein. In vitro processing and protein sequencing suggested that pro-GehC(WM) is possibly processed by extracellular glutamyl endopeptidase, PROM. Inductively coupled plasma-atomic emission spectrometer analysis showed that purified his-tagged mature GehC(WM) possessed zinc ion. A gehC(WM) knockout mutant was constructed by insertion of an erythromycin resistance gene into the gehC(WM). Zymogram and immunoblot analyses of the gehC(WM )mutant indicated that GehC(WM) was a major extracellular lipase of S. warneri M.  相似文献   

16.
The cultivation conditions of wild-type strain V-10 and mutant strain M-1 (overproducer of endonuclease and chitinase) of Serratia marcescens optimal for extracellular lipase biosynthesis were determined. The strain V-10 displayed the maximal lipase yield (840 AU/ml) after 10-12 h of cultivation; the strain M-1 (33 AU/ml), after 25-30 h. The data showed that extracellular lipases from V-10 and M-1 can be precipitated in a weakly acid medium (pH 5.0 and 4.5, respectively). This property was used to obtain partially purified lipase preparations. The effect of the ionic composition of the reaction mixture on the activities of these enzymatic preparations was studied. Both preparations displayed highest activities in weakly alkaline media (pH 8.0); however, the wild-type strain lipase displayed a higher thermal stability and stability at alkaline pH compared with M-1 lipase. Both lipases were activated by various anionic and nonionic surfactants and inactive in the presence of cetyltrimethylammonium bromide.  相似文献   

17.
Selective separation and purification of two lipases form Chromobacterium viscosum were carried out by liquid-liquid extraction using a reversed micellar system. Optimum parameters for extraction were determined using a 250 mM AOT micellar solution in isooctane. Complete separation of the two lipases was achieved at pH 6.0 with a 50mM potassium phosphate buffer solution containing 50 mM KCI. By adding 2.5% by volume of ethanol to the lipase-loaded micellar solution, 85% of the extracted lipase could be recovered in a new aqueous phase, 50 mM K(2)HPO(4) with 50 mM KCl, at pH 9.0. Lipase A was purified 2.6-fold with a recovery of 86%, and lipase B by 1.5-fold with a recovery of 76%.  相似文献   

18.
Interest on lipases from different sources (microorganisms, animals and plants) has markedly increased in the last decade due to the potential applications of lipases in industry and in medicine. Microbial and mammalian lipases have been purified to homogeneity, allowing the successful determination of their primary aminoacid sequence and, more recently, of the three-dimensional structure. The X-ray studies of pure lipases will enable the establishment of the structure-function relationships and contribute for a better understanding of the kinetic mechanisms of lipase action on hydrolysis, synthesis and group exchange of esters. This article reviews the separation and purification techniques that were used in the recovery of microbial, mammalian and plant lipases. Several purification procedures are analysed taking into account the sequence of the methods and the number of times each method is used. Novel purification methods based on liquid-liquid extraction, membrane processes and immunopurification are also reviewed.  相似文献   

19.
cDNA cloning and characterization of Geotrichum candidum lipase II   总被引:4,自引:0,他引:4  
Geotrichum candidum produces two extracellular lipases, I and II. A lipase II cDNA clone was isolated from a cDNA library by colony hybridization using the 32P-labeled fragment of lipase I cDNA isolated previously. The nucleotide sequence of lipase II cDNA determined by the dideoxy chain terminating method includes the N- and C-terminal amino acid sequences of lipase II, and the overall amino acid composition deduced from the cDNA coincides with that deduced on amino acid analysis of this protein. The cloned lipase II cDNA codes a protein of 544 amino acids and a part of the signal sequence of 13 amino acids. The peptide chain lengths of lipases I and II are the same, their overall identity being 84%. Furthermore, four Cys residues are completely conserved, which may participate in the formation of disulfide bridges. A homology search indicated that the G. candidum lipases and Candida cyclindracea lipase are homologous enzymes and that they are members of the cholinesterase family.  相似文献   

20.
Alcohol/salt-based aqueous two-phase systems (ATPSs) were used to recover lipase derived from Burkholderia pseudomallei (B. pseudomallei). Nine biphasic systems, comprised of an alcohol-based top phase (ethanol, 2-propanol and 1-propanol) and a salt-based bottom phase (ammonium sulfate, potassium phosphate and sodium citrate), were evaluated for their effectiveness in lipase recovery. The stability of lipase in each of the solutions was tested, and phase diagrams were constructed for each system. The optimum partition efficiency for the purification of lipase was obtained in an ATPS of 16% (w/w) 2-propanol and 16% (w/w) phosphate in the presence of 4.5% (w/v) NaCl. The purified lipase had a purification factor of 13.5 and a yield of 99%.  相似文献   

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