WO1997021822A2 - Methods and compositions for synthesis of oligosaccharides using mutant glycosidase enzymes - Google Patents
Methods and compositions for synthesis of oligosaccharides using mutant glycosidase enzymes Download PDFInfo
- Publication number
- WO1997021822A2 WO1997021822A2 PCT/CA1996/000841 CA9600841W WO9721822A2 WO 1997021822 A2 WO1997021822 A2 WO 1997021822A2 CA 9600841 W CA9600841 W CA 9600841W WO 9721822 A2 WO9721822 A2 WO 9721822A2
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- enzyme
- carboxylic acid
- amino acid
- mutant
- side chain
- Prior art date
Links
- YBDQLHBVNXARAU-UHFFFAOYSA-N CC1OCCCC1 Chemical compound CC1OCCCC1 YBDQLHBVNXARAU-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12N—MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
- C12N9/00—Enzymes; Proenzymes; Compositions thereof; Processes for preparing, activating, inhibiting, separating or purifying enzymes
- C12N9/14—Hydrolases (3)
- C12N9/24—Hydrolases (3) acting on glycosyl compounds (3.2)
- C12N9/2402—Hydrolases (3) acting on glycosyl compounds (3.2) hydrolysing O- and S- glycosyl compounds (3.2.1)
- C12N9/2405—Glucanases
- C12N9/2408—Glucanases acting on alpha -1,4-glucosidic bonds
- C12N9/2411—Amylases
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12N—MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
- C12N9/00—Enzymes; Proenzymes; Compositions thereof; Processes for preparing, activating, inhibiting, separating or purifying enzymes
- C12N9/14—Hydrolases (3)
- C12N9/24—Hydrolases (3) acting on glycosyl compounds (3.2)
- C12N9/2402—Hydrolases (3) acting on glycosyl compounds (3.2) hydrolysing O- and S- glycosyl compounds (3.2.1)
- C12N9/2405—Glucanases
- C12N9/2408—Glucanases acting on alpha -1,4-glucosidic bonds
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12N—MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
- C12N9/00—Enzymes; Proenzymes; Compositions thereof; Processes for preparing, activating, inhibiting, separating or purifying enzymes
- C12N9/14—Hydrolases (3)
- C12N9/24—Hydrolases (3) acting on glycosyl compounds (3.2)
- C12N9/2402—Hydrolases (3) acting on glycosyl compounds (3.2) hydrolysing O- and S- glycosyl compounds (3.2.1)
- C12N9/2405—Glucanases
- C12N9/2434—Glucanases acting on beta-1,4-glucosidic bonds
- C12N9/2445—Beta-glucosidase (3.2.1.21)
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12P—FERMENTATION OR ENZYME-USING PROCESSES TO SYNTHESISE A DESIRED CHEMICAL COMPOUND OR COMPOSITION OR TO SEPARATE OPTICAL ISOMERS FROM A RACEMIC MIXTURE
- C12P19/00—Preparation of compounds containing saccharide radicals
- C12P19/04—Polysaccharides, i.e. compounds containing more than five saccharide radicals attached to each other by glycosidic bonds
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12Y—ENZYMES
- C12Y302/00—Hydrolases acting on glycosyl compounds, i.e. glycosylases (3.2)
- C12Y302/01—Glycosidases, i.e. enzymes hydrolysing O- and S-glycosyl compounds (3.2.1)
- C12Y302/01021—Beta-glucosidase (3.2.1.21)
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07K—PEPTIDES
- C07K2319/00—Fusion polypeptide
- C07K2319/01—Fusion polypeptide containing a localisation/targetting motif
- C07K2319/02—Fusion polypeptide containing a localisation/targetting motif containing a signal sequence
Definitions
- This application relates to methods and compositions for synthesizing oligosaccharides, and to the oligosaccharide products which can be obtained using such methods and compositions .
- Oligosaccharide are compounds with considerable potential both as therapeutics and as reagents for clinical assays.
- the very nature of the saccharide subunits makes the synthesis of many oligosaccharide of potential interest a daunting task because of the many possibilities for formation of positional isomers in which different substituent groups on the sugars become involved in bond formation and potential for the formation of different anomeric fo ms. Because of these factors, chemical synthesis of most oligosaccha ides while possible is not generally feasible on a commercial scale because of poor yields of the desired product.
- oligosacchar ⁇ ides An alternative to chemical synthesis of oligosacchar ⁇ ides is enzymatic synthesis.
- enzymatic synthesis using glycosyl transferases, glycosidases or combinations thereof has been considered as a possible approach to the synthesis of oligosaccharides.
- Glycosyl transferases can be very effective for producing specific products with good stereochemical and regiochemical control, if a transferase with the desired specificity is available.
- the enzymes can be expensive and hard to handle since they are often membrane-associated and unstable, however, and the required nucleotide sugar substrates can be quite expensive.
- glycosyl transferases possessing the desired specif ici ty to make many sal ting oligosaccharides are not available .
- oligosaccharide synthesis can be achieved by adding a second sugar to the reaction mixture which competes with water and reacts m its place with the first sugar in a transglycosylation reaction.
- Glycosidases are generally available and easy to handle and have the potential to make many different products using inexpensive substrates. Unfortunately, it is difficult to control the reverse hydrolysis reaction which leads to poor product yields.
- stereochemical control i.e., the formation of only one anomer
- regiochemis ry i.e., the formation of 1-2 vs 1-3 vs 1-4 vs 1-6 bonds
- a first aspect of the present invention is a method for forming an oligosaccharide.
- a mixture of a glycosyl donor and a glycoside acceptor molecule is prepared.
- the glycosyl donor is selected from among molecules having substitu ⁇ ents at the 1-position which are good leaving groups.
- glycosyl donor s then enzymatically coupled to the glycoside acceptor molecule to form a glycosyl glycoside product using a mutant glycosidase enzyme in which one of two key arruno acids has been changed, and the glycosyl glycoside product is recovered.
- the mutant enzyme is one in which the normal nucleophilic amino acid within the active site had been changed to a non-nucleophilic ammo acid.
- the mutant enzyme in one in which the ammo acid which normally functions as a base has been replaced by a non-iomzable ammo acid.
- the glycosyl donor is selected to have the opposite anome ⁇ c configuration from the desired product.
- a further aspect of the present invention is a mutant glycosidase enzyme of the retaining type, in which the normal nucleophilic amino acid within the active site has been changed to an ammo acid other than glutamic acid or aspartic acid.
- One such enzyme is a mutant form of Agrobacteri u (3-Glucosidase in which the normal glutamic acid residue at position 358 is replaced with an alanine residue.
- a further aspect of the present invention is a mutant glycosidase enzyme of the inverting type, in which the normal amino acid that functions as a base within the active site has been changed to a non-ionizable amino acid.
- Fig. 1 shows the hydrolysis of a disaccharide within the active site of a normal glycosidase enzyme which retains stereochemical configuration during hydrolysis;
- Fig. 2 shows the hydrolysis of a disaccharide within the active site of a normal glycosidase enzyme which inverts stereochemical configuration during hydrolysis
- Fig. 3 shows the synthesis of a disaccharide within the active site of a mutant glycosidase within the scope of the present invention.
- DETAILED DESCRIPTION OF THE INVENTION This invention relates to mutant forms of glycosidase enzymes.
- Glycosidase enzymes can be classified as being either "retainers” because they retain the stereochemistry of the bond being broken during hydrolysis, or “inverters” because they invert the stereochemistry of the bond being broken during hydrolysis.
- Normal stereochemistry retaining enzymes have two carboxylic acid groups in the active site of the enzyme as shown generally in Fig. 1.
- One of these groups functions as an acid/base catalyst (labeled as group 1 in Fig 1) and the other as a nucleophile (group 2 in Fig. 1) .
- the nucleophile group 2 forms a glycosyl-enzyme intermediate which is then cleaved by the acid/base catalyst group 1 to result m a hydrolyzed glycoside in which the stereochemistry has been maintained.
- Normal stereochemistry inverting enzymes also have two carboxylic acid groups the active site of the enzyme as shown generally in Fig. 2. In inverting enzymes, however, one of these groups functions as an acid catalyst (labeled as group 3 m Fig 2) and the other as a base catalyst (group 4 in Fig. 2) .
- the acid catalyst group 3 protonates the hemiacetal-hydroxyl group of the glycosyl donor molecule, making it a good leaving group, at the same time that the base catalyst group 4 deprotonates a donor molecule (water or HOR) allowing it to replace the leaving hydroxyl group with inversion of stereochemistry.
- the present invention provides mutant forms of both retaining and inverting enzymes which one of the two carboxylic acid ammo acids in the active site has been replaced with a different amino acid.
- Such mutations provide enzymes which do not catalyze the hydrolysis of oligosaccharides, but which nevertheless retain activity to synthesize oligosaccharides with good control over the stereochemistry and regiochemistry of reaction.
- Enzymes to which the methodology of the present invention may be employed include, for example, 3-Glucosidases, 3-galactosidases, 3-mannosidases, (3-N-acetyl glucosam dases, 3- N-acetyl galactosaminidases, 3-xylosidases, "fucosidases, cellu- lases, xylanases, galactanases, mannanases, hemicellulases, amylases, glucoa ylases, -glucosidases, ⁇ -galactosidases, ⁇ - mannosidases, ⁇ -N-acetyl glucosam idases, ⁇ -N-acetyl galactos- ammidases, ⁇ -xylosidases, ⁇ -fucosidases, neura midases/siali- dase
- Caldo- cellum sp. t Clost ⁇ dium sp., Esche ⁇ chia coli, Kluvero ⁇ iyces sp., Klebsiella sp . , Lactobacillus sp., Aspergillus sp., Staphylococ- cus sp., Lactobacillus sp., Butyrovibrio sp., Rummococcu ⁇ sp., Sulfolobus sp., Schizophyllum sp., Trichoderma sp., Cellulo onas sp.
- Preferred enzymes in accordance with the invention are mutant forms of retaining glycosidase enzymes.
- one of the two amino acid residues with the active carboxylic acid s de chains is changed to a different amino acid which does not act as a nucleophile (in the case of a retaining enzyme) or as a base catalyst (in the case of an inverting enzyme).
- the substitution will involve replacing the glutamic acid or aspartic acid residue of the wild-type enzyme with alanine, gly ⁇ cine, valine, leucine, isoleucine, serine, threonine, cysteine, methionine, asparagine, glutamine, histidine, proline, phenylala ⁇ nine, or tyrosine.
- the substituted amino acid will have a side chain of approximately equal or smaller size to the side chain of the wild-type amino acid residue to avoid signi ⁇ ficant changes to the size and shape of the active site.
- Enzymes mutated in this way are inactive with the normal substrates, and thus cannot hydrolyze oligosaccharide products. They can, however, catalyze the coupling of modified glycosyl donor molecules to modified acceptors, for example the coupling of an ⁇ -glycosyl fluoride donor to a 3-glycoside acceptor as shown in Fig. 3. This reaction proceeds with substantial yield because the reverse hydrolysis reaction does not occur, and with good stereochemical and regiochemical control.
- the site for mutation in a retaining glycosidase may be identified after trapping of the glycosyl-enzyme intermediate in the active site using one of the following approaches.
- the intermediate may be trapped by rapid denaturation of the enzyme, or a mutant thereof, after incubation in the presence of a substrate.
- the intermediate may be trapped using a modified substrate which forms a relatively stable glycosyl- enzyme intermediate.
- Possible modified substrates which could be used include 2-deoxy-2-halo glycosyl derivatives, 2-deoxy-2,2- dihalo glycosyl derivatives, 5-halo glycosyl derivatives, cyclitol epoxides, epoxyalkyl glycosides, glycosyl methyl triazenes and other glycosyl derivatives bearing a reactive functional group at their anomeric center.
- the labeled enzyme is then cleaved into peptides by use of a protease or by specific chemical degradation, and the peptide bearing the sugar label then located in a chromatogram or other separation method and its amino acid sequence determined. Comparison of this sequence with that of the intact enzyme readily identifies the amino acid of interest.
- Identification of the labeled peptide may be achieved by a number of methods. These could include use of a radio- labeled glycosyl derivative, then searching for the radiolabeled peptide(s); comparative peptide mapping by HPLC or by LC/MS; LC/MS-MS analysis of the peptides, monitoring in neutral loss mode for the loss of the sugar in the collision cell.
- the catalytic nucleophile may also be identified in the three-dimensional structure of the enzyme determined by X-ray crystallography or NMR spectroscopy by inspection of the active site region, searching for a Glu or Asp residue. This would be facilitated by the inclusion of a substrate or an analogue in the active site of the enzyme.
- the catalytic nucleophile may be identified by the generation of mutants in which each Glu and Asp residue which is shown to be highly conserved within a homologous (or analogous) family of enzymes has been replaced, individually, by Ala. Identification of the mutant which is capable of util ⁇ izing the "wrong" glycosyl fluoride as a substrate will thereby allow identification of the residue of interest.
- the site for mutation in an inverting glycosidase may be identified by inspection of the three dimensional structure, where available, or by mutation of each glutamic acid and aspar- tic acid residue which is conserved within a sequence-related family to alanine and assaying each mutant for its ability to synthesize oligosaccharides using the corresponding glycosyl fluoride (i.e, a ⁇ -glycosyl fluoride for an ⁇ -glycosidase mutant or an ⁇ -glycosyl fluoride for a -glycosidase mutant) .
- the mutant enzyme of the invention is prepared by replacing the glutamic acid at position 358 with another ammo acid, for example alanine.
- Mutant ⁇ - amylase (human or porcine) in accordance with the invention has the aspartic acid at position 197 replaced with another ammo acid, for example alanine, while yeast ⁇ -glucosidase the aspartic acid at position 216 is replaced.
- a mutant gene is prepared using site directed mutagenesis to arrive at the desired result.
- this involves the construc ⁇ tion of a plasmid containing the coding sequence for the wild- type gene, and isolation of single stranded DNA. Copies are then made of the isolated plasmid DNA using a template dependant DNA polymerase and a primer which overlaps the site of the desired mutation and which differs from the wild-type sequence in the manner necessary to yield the desired mutation.
- the mutated plasmid is then transformed into a host organism, e.g., E . col i Transformants are initially selected using a marker contained within the plasmid, and then further selected by sequencing of the expressed glycosidase enzyme to confirm the nature of the mutation.
- Mutant enzymes according to the invention may be purified from the growth medium of the host organism by column chromatography, for example on DEAE-cellulose if desired. High levels of purity are not required for use in catalyzing oligosaccharide synthesis, however, provided that impurities with wild-type glycosidase activity must be substantially absent.
- the enzymes of the invention are used to couple ⁇ modified glycosyl donors with glycoside acceptor Preferred donor molecules are glycosyl fluorides, although other groups which are reasonably small and which function as relatively good leaving groups can also be used.
- glycosyl donor molecules include glycosyl chlorides, acetates, propion- ates, and pivaloates, and glycosyl molecules modified with substituted phenols.
- the donor molecules may be monosaccharides, or may themselves contain multiple sugar moieties.
- Glycosyl fluorides can be prepared from the free sugar by first acetylat g the sugar and then treating it with HF/pyridine. This will generate the thermodynamically most stable anomer of the protected (acetylated) glycosyl fluoride. If the less stable anomer is desired, it may be prepared by converting the peracetylated sugar with HBr/HOAc or with HCL to generate the anomeric bromide or chloride. This intermediate is reacted with a fluoride salt such as silver fluoride to generate the glycosyl fluoride.
- a fluoride salt such as silver fluoride
- glycosyl donor molecules including many glycosyl fluorides can be purchased commercially. Thus a w de range of donor molecules are available for use the methods of the present invention.
- the glycoside acceptor used in the method of the present invention may be essentially any glycoside molecule containing from 1 to 10 sugar moieties. The acceptor molecule may be substituted at positions away from the group which is coupled by the enzyme. Thus, the glycoside acceptor may be a monosaccharide, an oligosaccharide, or a sugar-containing molecule such as an aminoglycoside antibiotic.
- the glycoside acceptor used is a 3-glycoside acceptor, and vice versa.
- the acceptor and donor are combined in an aqueous buffer (for example 250 mM sodium phosphate buffer, pH 7.0 or 250 mM ammonium carbonate buffer, pH 7.75) in a mole ratio (acceptor/donor) of about 1 to 2.5, more preferably 1.1 to 2.0 together with a catalytic amount (i.e., about 0.02 to 0.5 mg/ml) of mutant enzyme and incubated at around 25 °C for a period of time sufficient to produce significant yields of product, for example 12 hours to 4 days.
- an aqueous buffer for example 250 mM sodium phosphate buffer, pH 7.0 or 250 mM ammonium carbonate buffer, pH 7.75
- acceptor/donor mole ratio of about 1 to 2.5, more preferably 1.1 to 2.0
- a catalytic amount i.e., about 0.02 to 0.5 mg/ml
- the reaction mixture is combined with 5 volumes of methanol, filtered through a silica plug (5 cm) and concentrated in vacuo.
- the mixture is co- evaporated with water (3 times) in vacuo.
- the residues from either procedure are then dissolved in acetonitrile/methanol, filtered and purified by silica gel chromatography or HPLC.
- the purified product can then be dissolved in water and freez2-dried or crystallized to yield a solid product.
- a fusion protein n which the mutant glycoside is engineered onto another protein with high affinity for an insoluble matrix.
- a fusion protein vith a cellulose binding protein prepared in the manner described by Ong et al., "Enzyme Immobilization Using the Cellulose-Binding Domain of a Cel l ulo onas fimi Exoglucanase" , Biotechnol ogy 7: 604-607 (1989) could be used in accordance with the invention.
- the method of the invention can be used to make a wide variety of oligosaccharides.
- Particularly useful oligosicchar- ides which can be made by this method include cello-oligDsacchar- ides and cello-oligosaccharide glycans which are very difficult to synthesize chemically but which are of interest because of their use in the study of cellulases, and oligosaccharide-based activators of cellulases which can be used to study cellulase activity and which have potential as antifungal agents, particularly the control of wood degrading fungi.
- Axother application of the present invention is the synthesis of malto- oligosaccharide derivatives with a -linked sugar (glucose, galactose, mannose, fructose, N-acetylglucosamine) attached at the non - reducing end .
- a -linked sugar glucose, galactose, mannose, fructose, N-acetylglucosamine
- Plasmid pTZl ⁇ Rabg was constructed by taking the coding sequence of the 3-glucos ⁇ dase gene (abg) from pABG5 (Wakarchuk et al., 1986) and inserting t into pTZ18R. JM101 was maintained on M9 minimal media. Plasmid containing strains were grown in Luna broth containing 100 ug/mL ampillicin.
- Single-stranded DNA was isolated by the following method. Cultures were grown on TYP (16g/L tryptone, 16g/L yeast extract, 5g/L NaCl, 2.5g/L K2HP04) medium containing lOOug/mL ampicillin and 109 PFU/mL helper phage M13K07 (Viera and Messing, 1988) . Kanamycm (50 ug/mL) was added 1 h after inoculation, and the culture was grown 6-10 h at 37°C. Phagemid were precipitated with 1.7 M ammonia acetate and 12% (w/v) PEG-6000.
- TYP 16g/L tryptone, 16g/L yeast extract, 5g/L NaCl, 2.5g/L K2HP04
- Kanamycm 50 ug/mL
- Phagemid were precipitated with 1.7 M ammonia acetate and 12% (w/v) PEG-6000.
- T7 DNA polymerase was used for the extension reactions.
- the plasmid DNA (pTUG10NAbgE358A) was transformed into JM101.
- Transformants were selected on LB agar containing 2% 5-bromo-4-chloro- -indolyl- -D-glucopyranoside, ImM isopropyl-3-D-thiogalactopyranoside and 100 ug/mL ampillicin. Possible mutants were screened by singlertrack sequencing and confirmed by complete sequencing reactions. The entire c ding region of Agr ⁇ bacterium ⁇ -glucosidase was then sequenced to confirm that only the desired mutations was present.
- Agrobacterium E358A- -Glucosidase was purified by modification of the method employed for isolation of the native enzyme from E. coli . Kempton & Withers, (1992) Biochemis try, 31 , 9961, except that enzyme presence and activity was meas ⁇ red with 2, 4-dinitrophenyl- -D-glucoside with sodium azide (Wang et al. , (1994) J. Amer . Chem . Soc , 116 , 11594.
- Protein was expressed in E. coli JM101 from the lac promotor of pTZ18R. Cells grown overnight in 200 mL of Typ Amp media at 30°C were used to inoculate the fermentor (15-20 L) at a level of 0.5-1.0%. The cells were grown to 2 - O ⁇ 6(X) , treated with 0.1 mM IPTG and harvested when growth reached 6-7OD 600 .
- Cells were harvested by Sharpies continuous centrifugation at 31 000 x g and the cell paste stored at -20°C.
- the cell pellet from the 15 L culture was thawed at 25°C and resuspended in 1-2 mL of 50 mM sodium phosphate, 2 mM EDTA buffer, pH 7.0, per gram of cell paste.
- the mixture was then passed twice through a French pressure cell and cell debris removed by centrifugation ( 20 000 x g for 30 min.). Steptomycin sulphate was added to this extract to a concentration of 1.5% (w/v) .
- the mixture was stirred for 4 hr. at 4°C and then centrifuged (20 000 x g for 30 min.) to remove the precipitated nucleic acids.
- the extract was then loaded onto a DEAE-Sephacel column (45 cm x 5 cm) equilibrated with 50 mM sodium phosphate 2 mM EDTA buffer, pH 7.0.
- the column was eluted with 2 x 1 L linear gradient of 0-1 M sodium chloride in starting buffer.
- Fractions containing the highest activity of E358A ⁇ -glucosidase were pooled, dialyzed overnight against 50 mM sodium phosphate buffer, pH 7.0 and concentrated using Amicon Centiprep 30 centrifuge ultrafiltration devices. Silver stained SDS-PAGE showed the single column purification of E358A /3-glucosidase to be approximately 95% homogenous.
- the mass of the E358A mutant was confirmed to be 58 amu's lower than that of the wild- type enzyme by electrospray mass ⁇ pectrometry. Protein vas used without any further purification for transglycosylation experiments.
- EXAMPLE 2 ⁇ -Galactosyl fluoride (0.35 uunoles) and p-nitrophenyl- ⁇ -D-glucoside (0.22 mmoles) were dissolved in 3.0 ml of 250 mM ammonium carbonate buffer (pH 7.75). 25 ul of an 8.75 ng/ml stock solution of E358A -glucosidase was added. After incubation at 25°C for 48 hours, TLC analysis (Merck Kii.selgel 60 F-254 plates, solvent system 7:2:1 ethyl acetate, metha:_ol, water) indicated the reaction had gone to completion.
- EXAMPLE 3 ⁇ -Glucosyl fluoride was coupled to a variety of aryl - glucoside acceptors using E-358A 3 -glucosidase. Reactions were run at a donor to acceptor mole ratio of 1.1 - 1.3 in ammonium carbonate buffer (pH 7.7) for a period of 48 hours. The products were recovered and purified by silica gel chromatography or HPLC, and analyzed by : H NMR and Mss Spectroscopy.
- EXAMPLE 4 To evaluate the effect of the donor molecule on the products formed, the experiment of Example 3 was repeated using different aryl-glycosides as donors. The results of this experiment are shown in Table 2. As can be seen, selection of the nature of the donor moiety in some cases shifts the reaction to the production of 3-1,3 linkages, but in each case still produced a good yield of product.
- EXAMP g 7 A transglyco ⁇ ylation reaction according to the invention waa performed to couple ⁇ -galactosyl fluoride *ith p- nitrophenyl- ⁇ -D-malto ⁇ ide. Reactions were run at a donor to acceptor mole ratio of 1.1 - 1.4 in ammonium carbonate buffer (pE 7.7) for a period of 48 hours. The products were recovered and purified by HPLC, and analyzed by 1 H NMR and mass spectroscopy. p-Nitrophenyl-4'-0-[3-D-galactopyrano ⁇ yl]- ⁇ -D-malto ⁇ ide was recovered in 64% yield.
- This product was deprotected by suspending a sample of the glycoside (70 mg) in dry methanol (15 mL) and adding acetyl chloride (1 mL) . This reaction mixture was stirred for 24 h at 4 C, then solvent removed by evaporation in vacuo, and the product crystallized from ethanol.
- a sample of ⁇ -glucosidase 400 ug, 7.8 mg/mL was inactivated with 2F-DNPG (0.32 mM) in 50 mM sodium phosphate buffer, pH 6.8 at 37 C C by incubation for 5 minutes.
- the labeled enzyme was then completely digested using 1:100 pepsin (w/w; enzyme:substrate) in 50 mM sodium phosphate buffer, pH 2.0, at room temperature.
- the proteolytic digest (10 ug) was loaded onto a C18 column (Reliasil, 1 x 150 mm) , then eluted with a gradient of 0-60% solvent B over 20 minutes followed by 100% B for 2 minutes at a flow rate of 50 ⁇ l/minute.
- Protein or peptide samples were separated by reverse phase HPLC on an Ultrafast Microprotein Analyzer (Michrom BioResources Inc., Pleasj.nton, CA) directly interfaced with the mass spectrometer, using solvent A: 0.05% tri luoroacetic acid, 2% acetonitrile in water and solvent B: 0.045% trifluoroacetic acid, 80% acetonitrile in watt;r.
- solvent A 0.05% tri luoroacetic acid, 2% acetonitrile in water
- solvent B 0.045% trifluoroacetic acid, 80% acetonitrile in watt;r.
- a post-column flow splitter was used to introduce 15% of ( :he HPLC eluate into the mass spectrometer, while 85% was collecied for further analysis.
- Intact protein samples (10 ⁇ g, native or labeled) were introduced into the mass spectrometer through a microbore PLRP column (1 X 50 mm) on the Michrom HPLC system (solvent system: 20-100% solvent B over 10 minutes, 100% solvent B over 2 minutes) .
- the quadrupole mass analyzer (in the single quadrupole mode) was scanned over a m/z range 300-2400 Da with a step size of 0.5 Da and a dwell time of 1 ⁇ _ per step.
- the ion source voltage (ISV) was set at 5 kV and the orifice energy (OR) was 80 V. Protein molecular weights were determined from this data using the deconvolution software supplied by Sciex.
- ester linkage between the 2FGlu label and the peptide is one of the more labile linkages present, readily susceptible to homolytic cleavage. Indeed, the collision conditions employed were sufficient to break the ester bond but not generally the peptide bonds. This results in the loss of a neutral 2FGlumoiety, leaving the peptide moiety with its original
- the two quadrupoles are then scanned in a linked manner such that only ions differing in m/z by the mass correspcnding to the label can pass through both quadrupoles and be detected. In some cases, however, it may be necessary to scan for /z differences of one half or one third the mass of the neut.ral species as the peptide may be doubly or triply charged.
- the identity of this peptide can be easily prob_d by calculation of its mass.
- the labeled peptide observed of m/z 871 corresponds to an unlabeled peptide 706 Da while that at m/zl035 corresponds to a peptide of mass 870 Da.
- a search of the amino acid sequence of Abg for all possible peptides of mass 730 Da and 870 Da containing the same Glu or Asp residue produced a short list of candidates from which the true sequence was determined by MS/MS analysis.
- EXAMPLE 9 A fusion protein combining the E358A mutant of Agrobac eriiim (.-glucosidase and the cellulose-binding domain of Cel l ulomonas fimi was prepared using the general approach of Ong
- Plasmid pTUG10NAbgE358A (encoding AbgE358A) and plasmid pEOl (encoding Abg-CBDcex) were each cut with Avr II and Sph I.
- the 0.78 kb fragment liberated from pTUG10NAbgE358A carrying the mutation was isolated by GeneClean as was the 4.2 Kb fragment from pEOl.
- the two fragments were ligated together (T4 DNA ligase) effectively replacing the corresponding wild-type fragment in pEOl with the mutation.
- the ligation mixture was transformed to electrocompetent E. coli DH5 ⁇ F'. Ampicillin resistant clones were selected and the plasmid DNA isolated by the Quiagen method. This yielded pAMC (encoding AbgE358A-CBDcex) .
- the mutation was confirmed by sequencing and mass spectroscopy.
- the plasmid was transformed to electrocompetent E. coli TB-1 for expression of the recombinant protein.
- the host organism is grown under inducing conditions. Cells are harvested by centrifugation, washed and broken in a French press. PMSF and pepstatin are immediately added to inhibit proteolysis after which cellular debris is removed by centrifugation. Fusion protein is then purified by cellulose affinity chromatography on Whatman CF1 cellulose, followed by elution and concentrated by ultrafiltration. The purified fusion protein may be immobilized on a cellulose matrix for use in oligosaccharide synthesis. The presence of the mutant E358A can be confirmed by reaction with dinitrophenyl- -D- glucoside in the presence of sodium azide and/or by SDS-PAGE.
Landscapes
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Organic Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Engineering & Computer Science (AREA)
- Zoology (AREA)
- Wood Science & Technology (AREA)
- Genetics & Genomics (AREA)
- Bioinformatics & Cheminformatics (AREA)
- General Health & Medical Sciences (AREA)
- Biochemistry (AREA)
- General Engineering & Computer Science (AREA)
- Microbiology (AREA)
- Biotechnology (AREA)
- Biomedical Technology (AREA)
- Molecular Biology (AREA)
- Medicinal Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Preparation Of Compounds By Using Micro-Organisms (AREA)
- Enzymes And Modification Thereof (AREA)
Abstract
Description
Claims
Priority Applications (7)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US09/091,272 US6284494B1 (en) | 1995-12-12 | 1996-12-12 | Methods and compositions for synthesis of oligosaccharides using mutant glycosidase enzymes |
AT96942211T ATE220720T1 (en) | 1995-12-12 | 1996-12-12 | METHODS AND COMPOSITIONS FOR OLIGOSACCHARIDE SYNTHESIS AND USE OF MUTANT GLYCOSIDASE |
JP9521572A JP2000501607A (en) | 1995-12-12 | 1996-12-12 | Method for synthesizing oligosaccharides using mutant glycosidase enzyme and composition for synthesis |
EP96942211A EP0870037B1 (en) | 1995-12-12 | 1996-12-12 | Methods and compositions for synthesis of oligosaccharides using mutant glycosidase enzymes |
AU11354/97A AU722220B2 (en) | 1995-12-12 | 1996-12-12 | Methods and compositions for synthesis of oligosaccharides using mutant glycosidase enzymes |
DE69622429T DE69622429T2 (en) | 1995-12-12 | 1996-12-12 | METHOD AND COMPOSITIONS FOR OLIGOSACCHARID SYNTHESIS AND APPLICATION OF MUTANT GLYCOSIDASE |
US09/837,711 US7078194B2 (en) | 1995-12-12 | 2001-04-17 | Methods and compositions for synthesis of oligosaccharides using mutant glycosidase enzymes |
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US08/571,175 US5716812A (en) | 1995-12-12 | 1995-12-12 | Methods and compositions for synthesis of oligosaccharides, and the products formed thereby |
CA2,165,041 | 1995-12-12 | ||
CA002165041A CA2165041C (en) | 1995-12-12 | 1995-12-12 | Methods and compositions for synthesis of oligosaccharides, and the products formed thereby |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US08/571,175 Continuation-In-Part US5716812A (en) | 1995-12-12 | 1995-12-12 | Methods and compositions for synthesis of oligosaccharides, and the products formed thereby |
Related Child Applications (3)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09091272 A-371-Of-International | 1996-12-12 | ||
US09/091,272 A-371-Of-International US6284494B1 (en) | 1995-12-12 | 1996-12-12 | Methods and compositions for synthesis of oligosaccharides using mutant glycosidase enzymes |
US09/837,711 Continuation US7078194B2 (en) | 1995-12-12 | 2001-04-17 | Methods and compositions for synthesis of oligosaccharides using mutant glycosidase enzymes |
Publications (2)
Publication Number | Publication Date |
---|---|
WO1997021822A2 true WO1997021822A2 (en) | 1997-06-19 |
WO1997021822A3 WO1997021822A3 (en) | 1997-08-28 |
Family
ID=25678258
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/CA1996/000841 WO1997021822A2 (en) | 1995-12-12 | 1996-12-12 | Methods and compositions for synthesis of oligosaccharides using mutant glycosidase enzymes |
Country Status (1)
Country | Link |
---|---|
WO (1) | WO1997021822A2 (en) |
Cited By (23)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1998046784A1 (en) * | 1997-04-11 | 1998-10-22 | The University Of British Columbia | Improved synthesis of oligosaccharides using activated glycoside derivatives |
WO1999057258A1 (en) * | 1998-05-01 | 1999-11-11 | The Procter & Gamble Company | Laundry detergent and/or fabric care compositions comprising a modified transferase |
WO2004024908A1 (en) * | 2002-09-12 | 2004-03-25 | The University Of British Columbia | Engineered enzymes and their use for synthesis of thioglycosides |
KR100440237B1 (en) * | 2002-10-15 | 2004-07-15 | 학교법인 성균관대학 | Synthesis of galactooligosaccharide by Thermus caldophilus GK24 β-glycosidase and high-level expression system of recombinant Thermus caldophilus GK24 β-glycosidase for use in the synthesis |
JP2009184953A (en) * | 2008-02-05 | 2009-08-20 | Tokyo Institute Of Technology | Method for producing aryl o-glucoside |
US8143049B2 (en) | 2008-08-29 | 2012-03-27 | Iogen Energy Corporation | Modified beta-glucosidases with improved stability |
US8716240B2 (en) | 2001-10-10 | 2014-05-06 | Novo Nordisk A/S | Erythropoietin: remodeling and glycoconjugation of erythropoietin |
US8716239B2 (en) | 2001-10-10 | 2014-05-06 | Novo Nordisk A/S | Granulocyte colony stimulating factor: remodeling and glycoconjugation G-CSF |
US8841439B2 (en) | 2005-11-03 | 2014-09-23 | Novo Nordisk A/S | Nucleotide sugar purification using membranes |
US8853161B2 (en) | 2003-04-09 | 2014-10-07 | Novo Nordisk A/S | Glycopegylation methods and proteins/peptides produced by the methods |
CN104140455A (en) * | 2014-06-12 | 2014-11-12 | 南京农业大学 | Novel combined type rice bran phenolic glycoside compound as well as preparation method and application thereof |
US8911967B2 (en) | 2005-08-19 | 2014-12-16 | Novo Nordisk A/S | One pot desialylation and glycopegylation of therapeutic peptides |
US8916360B2 (en) | 2003-11-24 | 2014-12-23 | Novo Nordisk A/S | Glycopegylated erythropoietin |
US8969532B2 (en) | 2006-10-03 | 2015-03-03 | Novo Nordisk A/S | Methods for the purification of polypeptide conjugates comprising polyalkylene oxide using hydrophobic interaction chromatography |
US9005625B2 (en) | 2003-07-25 | 2015-04-14 | Novo Nordisk A/S | Antibody toxin conjugates |
US9029331B2 (en) | 2005-01-10 | 2015-05-12 | Novo Nordisk A/S | Glycopegylated granulocyte colony stimulating factor |
US9050304B2 (en) | 2007-04-03 | 2015-06-09 | Ratiopharm Gmbh | Methods of treatment using glycopegylated G-CSF |
US9150848B2 (en) | 2008-02-27 | 2015-10-06 | Novo Nordisk A/S | Conjugated factor VIII molecules |
US9187532B2 (en) | 2006-07-21 | 2015-11-17 | Novo Nordisk A/S | Glycosylation of peptides via O-linked glycosylation sequences |
US9187546B2 (en) | 2005-04-08 | 2015-11-17 | Novo Nordisk A/S | Compositions and methods for the preparation of protease resistant human growth hormone glycosylation mutants |
US9200049B2 (en) | 2004-10-29 | 2015-12-01 | Novo Nordisk A/S | Remodeling and glycopegylation of fibroblast growth factor (FGF) |
US9493499B2 (en) | 2007-06-12 | 2016-11-15 | Novo Nordisk A/S | Process for the production of purified cytidinemonophosphate-sialic acid-polyalkylene oxide (CMP-SA-PEG) as modified nucleotide sugars via anion exchange chromatography |
US11248217B2 (en) | 2018-08-20 | 2022-02-15 | Rutgers, The State University Of New Jersey | Engineered carbohydrate-active enzymes for glycan polymers synthesis |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0226563A1 (en) * | 1985-12-11 | 1987-06-24 | Svenska Sockerfabriks AB | A method of controlling the regioselectivity of glycosidic bonds |
WO1987005936A1 (en) * | 1986-04-02 | 1987-10-08 | Johansson Hanna Maria E | Process for the manufacture of oligosaccharides |
WO1989009275A1 (en) * | 1988-03-24 | 1989-10-05 | Nilsson Kurt G I | A method for synthesis of oligosaccharides |
-
1996
- 1996-12-12 WO PCT/CA1996/000841 patent/WO1997021822A2/en active IP Right Grant
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0226563A1 (en) * | 1985-12-11 | 1987-06-24 | Svenska Sockerfabriks AB | A method of controlling the regioselectivity of glycosidic bonds |
WO1987005936A1 (en) * | 1986-04-02 | 1987-10-08 | Johansson Hanna Maria E | Process for the manufacture of oligosaccharides |
WO1989009275A1 (en) * | 1988-03-24 | 1989-10-05 | Nilsson Kurt G I | A method for synthesis of oligosaccharides |
Non-Patent Citations (8)
Cited By (27)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1998046784A1 (en) * | 1997-04-11 | 1998-10-22 | The University Of British Columbia | Improved synthesis of oligosaccharides using activated glycoside derivatives |
US5952203A (en) * | 1997-04-11 | 1999-09-14 | The University Of British Columbia | Oligosaccharide synthesis using activated glycoside derivative, glycosyl transferase and catalytic amount of nucleotide phosphate |
US6204029B1 (en) | 1997-04-11 | 2001-03-20 | The University Of British Columbia | Glycosylated acceptor synthesis catalyzed by glycosyl transferase and nucleotide phosphate sugar-dependent enzyme |
WO1999057258A1 (en) * | 1998-05-01 | 1999-11-11 | The Procter & Gamble Company | Laundry detergent and/or fabric care compositions comprising a modified transferase |
US8716239B2 (en) | 2001-10-10 | 2014-05-06 | Novo Nordisk A/S | Granulocyte colony stimulating factor: remodeling and glycoconjugation G-CSF |
US8716240B2 (en) | 2001-10-10 | 2014-05-06 | Novo Nordisk A/S | Erythropoietin: remodeling and glycoconjugation of erythropoietin |
WO2004024908A1 (en) * | 2002-09-12 | 2004-03-25 | The University Of British Columbia | Engineered enzymes and their use for synthesis of thioglycosides |
KR100440237B1 (en) * | 2002-10-15 | 2004-07-15 | 학교법인 성균관대학 | Synthesis of galactooligosaccharide by Thermus caldophilus GK24 β-glycosidase and high-level expression system of recombinant Thermus caldophilus GK24 β-glycosidase for use in the synthesis |
US8853161B2 (en) | 2003-04-09 | 2014-10-07 | Novo Nordisk A/S | Glycopegylation methods and proteins/peptides produced by the methods |
US9005625B2 (en) | 2003-07-25 | 2015-04-14 | Novo Nordisk A/S | Antibody toxin conjugates |
US8916360B2 (en) | 2003-11-24 | 2014-12-23 | Novo Nordisk A/S | Glycopegylated erythropoietin |
US10874714B2 (en) | 2004-10-29 | 2020-12-29 | 89Bio Ltd. | Method of treating fibroblast growth factor 21 (FGF-21) deficiency |
US9200049B2 (en) | 2004-10-29 | 2015-12-01 | Novo Nordisk A/S | Remodeling and glycopegylation of fibroblast growth factor (FGF) |
US9029331B2 (en) | 2005-01-10 | 2015-05-12 | Novo Nordisk A/S | Glycopegylated granulocyte colony stimulating factor |
US9187546B2 (en) | 2005-04-08 | 2015-11-17 | Novo Nordisk A/S | Compositions and methods for the preparation of protease resistant human growth hormone glycosylation mutants |
US8911967B2 (en) | 2005-08-19 | 2014-12-16 | Novo Nordisk A/S | One pot desialylation and glycopegylation of therapeutic peptides |
US8841439B2 (en) | 2005-11-03 | 2014-09-23 | Novo Nordisk A/S | Nucleotide sugar purification using membranes |
US9187532B2 (en) | 2006-07-21 | 2015-11-17 | Novo Nordisk A/S | Glycosylation of peptides via O-linked glycosylation sequences |
US8969532B2 (en) | 2006-10-03 | 2015-03-03 | Novo Nordisk A/S | Methods for the purification of polypeptide conjugates comprising polyalkylene oxide using hydrophobic interaction chromatography |
US9050304B2 (en) | 2007-04-03 | 2015-06-09 | Ratiopharm Gmbh | Methods of treatment using glycopegylated G-CSF |
US9493499B2 (en) | 2007-06-12 | 2016-11-15 | Novo Nordisk A/S | Process for the production of purified cytidinemonophosphate-sialic acid-polyalkylene oxide (CMP-SA-PEG) as modified nucleotide sugars via anion exchange chromatography |
JP2009184953A (en) * | 2008-02-05 | 2009-08-20 | Tokyo Institute Of Technology | Method for producing aryl o-glucoside |
US9150848B2 (en) | 2008-02-27 | 2015-10-06 | Novo Nordisk A/S | Conjugated factor VIII molecules |
US8143049B2 (en) | 2008-08-29 | 2012-03-27 | Iogen Energy Corporation | Modified beta-glucosidases with improved stability |
CN104140455B (en) * | 2014-06-12 | 2016-08-17 | 南京农业大学 | A kind of conjunction type Testa oryzae phenolic glycoside compound and its production and use |
CN104140455A (en) * | 2014-06-12 | 2014-11-12 | 南京农业大学 | Novel combined type rice bran phenolic glycoside compound as well as preparation method and application thereof |
US11248217B2 (en) | 2018-08-20 | 2022-02-15 | Rutgers, The State University Of New Jersey | Engineered carbohydrate-active enzymes for glycan polymers synthesis |
Also Published As
Publication number | Publication date |
---|---|
WO1997021822A3 (en) | 1997-08-28 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US5716812A (en) | Methods and compositions for synthesis of oligosaccharides, and the products formed thereby | |
EP0870037B1 (en) | Methods and compositions for synthesis of oligosaccharides using mutant glycosidase enzymes | |
WO1997021822A2 (en) | Methods and compositions for synthesis of oligosaccharides using mutant glycosidase enzymes | |
US5888776A (en) | Bacteria and enzymes for production of alternant fragments | |
Okuyama et al. | α-Glucosidase mutant catalyzes “α-glycosynthase”-type reaction | |
US7582463B2 (en) | Non-reducing saccharide-forming enzyme, trehalose-releasing enzyme, and process for producing saccharides using the enzymes | |
US7078194B2 (en) | Methods and compositions for synthesis of oligosaccharides using mutant glycosidase enzymes | |
Horaguchi et al. | Nigero-oligosaccharide production by enzymatic hydrolysis from alkaline-pretreated α-1, 3-glucan | |
JP4784224B2 (en) | Glycosyl transfer method and glycosyltransferase | |
CN112725313B (en) | Preparation and application of beta-galactosidase | |
US20030129723A1 (en) | Thermophilic endoglucanase | |
CA2238966A1 (en) | Methods and compositions for synthesis of oligosaccharides using mutant glycosidase enzymes | |
Bojarová et al. | N-Acetylhexosamine triad in one molecule: Chemoenzymatic introduction of 2-acetamido-2-deoxy-β-d-galactopyranosyluronic acid residue into a complex oligosaccharide | |
Ashida et al. | Syntheses of mucin-type O-glycopeptides and oligosaccharides using transglycosylation and reverse-hydrolysis activities of Bifidobacterium endo-α-N-acetylgalactosaminidase | |
JPH11318441A (en) | Ultra heat-resistant and ultra acid-resistant amylopullulanase | |
JP4012383B2 (en) | Method for producing modified α-glucosidase and oligosaccharide | |
Kawagishi et al. | Bacillus cereus autolytic endoglucosaminidase active on cell wall peptidoglycan with N-unsubstituted glucosamine residues | |
US6740509B2 (en) | Method for the production of mucin-type glycopeptide | |
KR102300386B1 (en) | Use of alpha-L-fucosidase having dual enzymatic activity for cleaving alpha- and beta-1,4-glycosidic linkages | |
US20030138880A1 (en) | Solid-phase synthesis of oligosaccharides and glycopeptides using glycosynthases | |
Kristová et al. | A chemoenzymatic route to mannosamine derivatives bearing different N-acyl groups | |
Guasch et al. | Cloning, overexpression, crystallization and preliminary X-ray analysis of a family 1 β-glucosidase from Streptomyces | |
Saadat et al. | Enzymic degradation of the mycobacterial O-methyl-D-glucose polysaccharide by a Rhizopus-mold alpha amylase, an enzyme active on 6-O-methyl-amylo-oligosaccharides | |
JPH08336395A (en) | Production of composite carbohydrate | |
Yamamoto | Modification and application of glycosidases to create homogeneous glycoconjugates |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AK | Designated states |
Kind code of ref document: A2 Designated state(s): AL AM AT AU AZ BA BB BG BR BY CA CH CN CU CZ DE DK EE ES FI GB GE HU IL IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MD MG MK MN MW MX NO NZ PL PT RO RU SD SE SG SI SK TJ TM TR TT UA UG US UZ VN AM AZ BY KG KZ MD RU TJ TM |
|
AL | Designated countries for regional patents |
Kind code of ref document: A2 Designated state(s): KE LS MW SD SZ UG AT BE CH DE DK ES FI FR GB GR IE IT LU MC NL PT SE BF BJ CF CG |
|
AK | Designated states |
Kind code of ref document: A3 Designated state(s): AL AM AT AU AZ BA BB BG BR BY CA CH CN CU CZ DE DK EE ES FI GB GE HU IL IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MD MG MK MN MW MX NO NZ PL PT RO RU SD SE SG SI SK TJ TM TR TT UA UG US UZ VN AM AZ BY KG KZ MD RU TJ TM |
|
AL | Designated countries for regional patents |
Kind code of ref document: A3 Designated state(s): KE LS MW SD SZ UG AT BE CH DE DK ES FI FR GB GR IE IT LU MC NL PT SE BF BJ CF CG |
|
DFPE | Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101) | ||
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
ENP | Entry into the national phase |
Ref document number: 1997 521572 Country of ref document: JP Kind code of ref document: A |
|
WWE | Wipo information: entry into national phase |
Ref document number: PA/a/1998/004709 Country of ref document: MX |
|
ENP | Entry into the national phase |
Ref document number: 2238966 Country of ref document: CA Kind code of ref document: A Ref document number: 2238966 Country of ref document: CA |
|
WWE | Wipo information: entry into national phase |
Ref document number: 1996942211 Country of ref document: EP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 09091272 Country of ref document: US |
|
REG | Reference to national code |
Ref country code: DE Ref legal event code: 8642 |
|
WWP | Wipo information: published in national office |
Ref document number: 1996942211 Country of ref document: EP |
|
WWG | Wipo information: grant in national office |
Ref document number: 1996942211 Country of ref document: EP |