摘要:
The present invention includes compositions and methods for making and using an isolated cyanobacterium that includes a portion of an exogenous bacterial cellulose operon sufficient to express bacterial cellulose, whereby the cyanobacterium produces extracellular glucose. The compositions and methods of the present invention may be used as a new global crop for the manufacture of cellulose, CO2 fixation, for the production of alternative sources of conventional cellulose as well as a biofuel and precursors thereof.
摘要:
The present invention includes compositions and methods for the integration of a non-allergenic nanocellulose into a wound bed. The composition may be formed into a wide variety of implants, e.g., a suture, a sheet, a compress, a bandage, a band, a prosthesis, a fiber, a woven fiber, a bead, a strip, a clasp, a prosthesis, a catheter, a screw, a bone plate, a pin, a bandage or combinations thereof.
摘要:
The present invention involves a process for screening for and isolating spontaneously occurring or induced cellulose II-producing microorganisms. The process comprises a series of steps in various embodiments. Initially, cellulose-producing microorganisms from a first culture are plated out on a nutrient agar plate. The nutrient agar plate is then incubated to facilitate formation of colonies from single microorganisms. Samples of liquid nutrient medium are then inoculated with microorganisms from colonies having a smooth configuration, as compared to the usual rough colony configuration. The inoculated samples are then aerobically incubated to facilitate microorganism proliferation and pellicle formation. From these incubated samples are selected microorganisms, which, after a cultivation period, have proliferated but not formed a pellicle. Said selected microorganisms produce cellulose II instead of the cellulose I produced by pellicle-forming organisms.
摘要:
A method of producing cellulose of amorphous character by subjecting cellulose-producing organisms to a magnetic field substantially greater than 0.5 gauss and preferably at least about 500 gauss. The cellulose produced in the presence of a magnetic field is of an amorphous nature with increased water absorptivity and decreased crystallinity.
摘要:
The present invention discloses a method of synthesizing a novel form of cellulose I as well as methods of synthesizing a novel form of cellulose I in vitro. One method comprises contacting an activated saccharide substrate with an endoglucanase in an appropriate organic solvent/buffer ratio. The invention also encompasses a partially purified endoglucanase and a method of synthesizing cellooligosaccharides. A second method comprises contacting a nucleotide sugar with a purified glycosyl transferase in an appropriate buffer medium to insure polymerization and crystallization of parallel glucan chains from the enzyme/micelle complex to form cellulose I.
摘要:
Disclosed are improved methods for preparing high resolution replicas for electron microscopic analysis. Replicas are prepared having a resolution capability less than ten angstroms, with structures of even less than five angstroms being readily discernible. Particular aspects of the invention concern the use of a platinum/carbon evaporant to prepare extremely thin replica surfaces which allow the visualization of structures heretofore unresolvable. The replication is performed at high vacuum, on the order of 10.sup.-5 Torr or better, with continuous rotation of the sample to allow for an even distribution of the evaporant. The resultant replica surfaces are on the order of no more than 5 to 10 angstroms thick. The replica technology disclosed herein is applicable to both biological as well as non-biological samples, including tissues, biochemicals, metals and polymers and even computer chips and superconductor surfaces.
摘要:
The present invention includes a method, apparatus and system for nanofabrication in which one or more target molecules are identified for manipulation with an electron beam and the one or more target molecules are manipulated with the electron beam to produce new useful materials.
摘要:
The present invention comprises a biologically pure culture of a cellulose-producing microorganism, preferably a prokaryote. This cellulose-producing microorganism is capable, during fermentation in an aqueous nutrient medium containing assimilable sources of carbon, nitrogen and inorganic substances, of reversal of direction of cellulose ribbon extrusion. This reversal of direction of cellulose ribbon extrusion results on the cellulose-producing microorganism shuttling, at least periodically, first in one direction and then in the other direction along a length of an earlier-deposited cellulose ribbon to add another cellulose ribbon thereto and produce a cellulose ribbon-bundle having a width of at least two cellulose ribbons.The cellulose-producing microorganism of the present invention may be of the genus Acetobacter, Agrobacterium, Rhizobium, Pseudomonas or Alcaligenes, preferably of the genus Acetobacter and more preferably of the species Acetobacter xylinum or Acetobacter pasteurianus. Among preferred Acetobacter xylinum strains are strain N05, H1A; H1B; H1C; H2A; H2B; H5C; H5D; H6C; H8C; H8G; H14B; H15A; and H15B. Acetobacter xylinum strain N05, the most preferred strain, has identifying characterisitcs of ATCC 53582 on deposit with the American Type Culture Collection, Rockville, MD.
摘要:
The present invention involves a method of producing cellulose. This method comprises inoculating a quantity of nutrient medium comprising a polysaccharide derivative such as carboxymethylcellulose (CMC) with a cellulose-producing microorganism. The inoculated medium is then aerobically incubated to facilitate the production of cellulose. The step of substantially drying the cellulose may be added for certain products. Substantially dried cellulose resulting from this procedure is highly absorbent, tending to retain its absorbent properties during repeated wetting and drying, and is usable where such absorbency is desired.A subject of the present invention is a composition of matter consisting essentially of such cellulose in a native or substantially dried form. Microbial cellulose produced in the presence of carboxymethyl cellulose may be substantially dried by many means known to those skilled in the art. This drying may be, for example, by washing with a non-aqueous hydrophilic solvent or by air-drying. Preferred non-aqueous solvents include alkyl alcohols or ketones having less than about six carbon atoms. When such non-aqueous solvents are used to dry the CMC-produced cellulose, the dried cellulose may have a resilient structure and possibly an elastic nature.