The University of British Columbia

Sonosep Biotech Inc.

Douglas G Kilburn

Neil R Gilkes

Robert C Miller, Jr

Richard A Warren

Charles A Haynes

Robert C Miller

Anthony Warren

R Antony Warren

James M Piret

Eric Jervis

Felix Trampler

Keith Richard Humphries

Robin Fredrick Turner

Michael R Phelps

James G Doheny

Peter Tomme

Judie Alimonti

R Anthony Warren

Stefan A Sonderhoff

Methods and compositions are provided for the modification of polysaccharide structures using polysaccharidase binding or catalytic domains either alone or in tandem to modify the structure of polysaccharides. These methods and compositions are exemplified by the use of cellulase binding and catalytic domains to polish cotton, and to alter dying characteristics, texture and porosity of cellulose fibers.

Method and compositions for modification of polysaccharide characteristics

A compound having a polysaccharide binding domain such as contained by a cellulose and essentially lacking in polysaccharidase activity is purified from other ingredients in a mixture using an affinity partition system. A mixture containing the compound is contacted with a system containing as a first phase an aqueous solution of oligosaccharide polymer such as cellulose and as a second phase a solution of a polymer such as a poly(ethylene glycol)-poly(propylene glycol) copolymer. The compound petitions into the first phase and binds to the oligosaccharide polymer, preferably with a K,of 10,to 10,, to form a complex. The complex is collected, and the compound is dissociated from the oligosaccharide polymer. The compound may be formed of a non-peptide chemical moiety or a peptide moiety linked to a polypeptide having the polysaccharide binding domain. The compound may also be a fusion polypeptide containing the polysaccharide binding domain linked through a protease recognition sequence to a macromolecule such as an enzyme, a hormone or an antibody. The macromolecule can be removed by using a protease to cleave the recognition sequence. Another partition system contains the oligosaccharide polymer and a phase separation inducing agent such as a sulfate or citrate salt that induces separation to produce different phases.

Purification of a polypeptide compound having a polysaccharide binding domain by affinity phase separation

Novel polypeptide compositions and methods for their use are provided comprising fusion proteins in which the polysaccharide binding domain or functional portion thereof of a polysaccharidase is fused to a heterologous protein or is conjugated to a chemical moiety. The compositions can be synthesized or prepared by recombinant DNA technology. The compositions find use as removable labels.

Polysaccharide binding fusion proteins and conjugates

A two-phase partition system is provided for affinity separation of a composition containing a polysaccharide binding peptide from a mixture such as a fermentation broth. The peptide may be from an enzyme and lacking in polysaccharidase activity such as the binding domain of cellulase that binds to cellulose. The system contains a phase-forming oligosaccharide polymer such as a cellulose derivative to which the peptide binds with a Ka of 10.sup.3 M to 10.sup.7 M, and a phase inducing agent such as a polyethylene glycol polymer, or a salt present at sufficiently high concentration to induce phase separation. If the oligosaccharide polymer is thermoseparating, phase separation can be induced by heating. Using the system involves contacting a composition containing the peptide such as a fusion protein with the system, partitioning the composition into a phase containing the oligosaccharide polymer by binding to the polymer and recovering the polymer containing the bound composition. The peptide or a fusion protein containing the peptide can be contacted with a cell having a carbohydrate residue to which the peptide binds to form a complex, and the complex is separated with the system to produce a bound cell composition. The peptide may be linked through a protease recognition sequence to a macromolecule such as an enzyme, a hormone or an antibody, and the macromolecule can be removed by using a protease to cleave the recognition sequence.

Two-phase partition affinity separation system and affinity separated

Fusion proteins or conjugates are provided containing an amino acid sequence having a substrate binding region of a polysaccharidase such as cellulase that binds to a .beta.-1,4-glycan matrix such as cellulose. The substrate binding region is essentially without polysaccharidase activity. In the fusion protein, the substrate binding region is fused or chemically linked to a polypeptide such as an enzyme, a hormone, an immunoglobulin or a protein dye. By contacting the fusion protein with a .beta.-1,4-glycan matrix, the substrate binding region binds to the matrix to immobilize the polypeptide on the matrix. The polypeptide or fusion protein can be removed from the matrix with a protease acting on a protease recognition sequence or with a solution having a low ionic strength or high pH. In the conjugate, the substrate binding region is joined such as by covalent bonding to a non-protein chemical moiety such as a dye, chromophore, fluorescor, radionuclide or enzyme co-factor. By contacting the conjugate with a .beta.-1,4-glycan matrix, the substrate binding region binds to the matrix to immobilize the chemical moiety on the matrix. The conjugate or chemical moiety can be removed with a protease acting on a protease recognition sequence or with a solution having a low ionic strength or high pH.

Fusion proteins or conjugates are provided containing an amino acid sequence having a substrate binding region of a polysaccharidase such as cellulase that binds to a .beta.-1,4-glycan matrix such as cellulose. The substrate binding region is essentially without polysaccharidase activity. In the fusion protein, the substrate binding region is fused or chemically linked to a polypeptide such as an enzyme, a hormone, an immunoglobulin or a protein dye. By contacting the fusion protein with a .beta.-1,4-glycan matrix, the substrate binding region binds to the matrix to immobilize the polypeptide on the matrix. The polypeptide or fusion protein can be removed from the matrix with a protease recognition sequence or with a solution having a low ionic strength or high pH. In the conjugate, the substrate binding region is joined such as by covalent bonding to a non-protein chemical moiety such as a dye, chromophore, fluorescor, radionuclide or enzyme co-factor. By contacting the conjugate with a .beta.-1,4-glycan matrix, the substrate binding region binds to the matrix to immobilize the chemical moiety on the matrix. The conjugate or chemical moiety can be removed with a protease acting on a protease recognition sequence or with a solution having a low ionic strength or high pH.

Conjugate of non-protein chemical moiety and polypeptide having

Methods and compositions are provided for in vitro expansion of growth factor dependent cells. Expansion is effected through the use of growth factor conjugates that include a growth factor such as a steel factor and a polysaccharidase substrate binding region. The conjugates are immobilized by binding of the substrate binding region to a substrate of the polysaccharidase in a growth chamber for the cells.

Compositions and methods for modulating cell proliferation using growth

Methods and compositions for modification of polysaccharide

A biologically pure DNA sequence which encodes an endo 1,4-.beta.-glucanase, useful for the efficient conversion of cellulose to glucose, is disclosed. Also disclosed are recombinant DNA cloning vehicles (vectors) that contain nucleotide sequences that encode for the aforesaid endoglucanase, proteins that exhibit endoglucanase activity, expression-controlling DNA sequences, microorganisms that contain recombinant DNA cloning vehicles, as well as messenger RNA sequences complementary to a DNA strand of the aforesaid DNA nucleotide sequences.

Characterization and structure of an endodglucanase gene of Cellulomonas

Particulate material suspended in a fluid is separated and recycled by means of an ultrasonic resonance wave. In a preferred embodiment, the ultrasonic resonance field is generated within a multilayered composite resonator system including a transducer, the suspension and a mirror parallel to each other. Dimensions and frequencies resonant to the whole system but not exciting Eigen-frequencies of transducer and mirror itself are chosen so that thermal dissipation is minimized. Criteria for flow direction and flow rate are defined in order to maintain a high-quality factor of the composite resonator and to achieve a high-separation efficiency. Generally, the process is suitable for all kinds of particles (solid, liquid or gaseous disperse phases) especially for hydrosols (particles in water) and for separation of biological particles such as mammalian, bacterial and plant cells or aggregates. Specialized applications in biotechnology are described including an acoustic filter for mammalian cell bioreactors or the selective retention of viable cells relative to non-viable cells.

Acoustic filter for separating and recycling suspended particles

A regenerable biosensor probe adapted for positioning in a bioreactor comprises a selectively permeable interface membrane, a porous protein-receiving matrix adjacent to the interface membrane, an indicating electrode, an inlet conduit through which fresh protein conjugate may flow to the protein-receiving matrix, and an outlet conduit through which spent protein conjugate may be removed from the protein-receiving matrix. A selectively permeable interface membrane, which may be used in a biosensor system to separate biochemical, optical or other processes from an analyte matrix comprises a supporting mesh, a perfluorosulfonic acid polymer impregnated substrate and a homogenous film of perfluorosulfonic acid polymer. A method of preparing this interface membrane comprises fixing a substrate on to a supporting mesh to form a substrate membrane, casting a perfluorosulfonic and polymer on the substrate membrane and curing the product to so formed.

Biosensor and interface membrane

A fusion protein that can function as a removable label is prepared containing a polypetide such as an enzyme and an amino acid sequence having a substrate binding region of a polysaccharidase such as cellulase that has essentially no polysaccharidase activity. By contacting the fusion protein with a .beta.-1,4 glycan matrix such as cellulose, the substrate binding region binds to the matrix to immobilize the polypeptide. The polypetide or fusion protein can be removed from the matrix with a protease capable of cleaving a specific protease cleavage site, or with a solution having a low ionic strength or a high pH. The fusion protein can be prepared by recombinant DNA technology.

Method of preparing a B-1,4 glycan matrix containing a bound fusion

A fusion protein is prepared containing a polypeptide such as an enzyme and an amino acid sequence having a substrate binding region of a polysaccharidase such as cellulase that has essentially no polysaccharidase activity. By contacting the fusion protein with an affinity matrix containing a substrate such as cellulose for the cellulase substrate binding region, the substrate binding region binds to the affinity matrix to immobilize the polypeptide. The polypeptide can be purified by separating the fusion protein or polypeptide from the affinity matrix. The polypeptide can be separated by cleaving the protein with a Cellulomonas fimi protease.

Cellulose binding fusion proteins having a substrate binding region of

A fusion protein is prepared containing a polypeptide such as an enzyme and an amino acid sequence having a substrate binding region of a polysaccharidase such as cellulase that has essentially no polysaccharidase activity. By contacting the fusion protein with an affinity matrix containing a substrate such as cellulose for the cellulase substrate binding region, the substrate binding region binds to the affinity matrix to immobilize the polypeptide. The polypeptide can be purified by separating the fusion protein or polypeptide from the affinity matrix.

Growing community of inventors

Vancouver, Canada

Douglas G Kilburn