摘要:
A method for preserving immobilized or unimmobilized microbial cells having nitrilase activity and for stabilizing the nitrilase activity of unimmobilized or immobilized microbial cells has been developed. The unimmobilized or immobilized microbial cells are stored in an aqueous solution containing from about 0.10 M to the saturation concentration of an inorganic salt of bicarbonate or carbonate, including ammonium, sodium and potassium salts of bicarbonate or carbonate. Aqueous suspensions containing at least 100 mM bicarbonate or carbonate limit microbial contamination of the stored enzyme catalyst, as well as stabilize the desired nitrilase activity of the uninmmobilized or immobilized cells. Microorganisms which are characterized by an nitrilase activity and are stabilized and preserved by this method include Acidovorax facilis 72-PF-15 (ATCC 55747), Acidovorax facilis 72-PF-17 (ATCC 55745), Acidovorax facilis 72W (ATCC 55746), and transformed microbial cells having nitrilase activity, preferably E. coli SS1001 (ATCC PTA-1177) which is transformed with Acidovorax facilis 72W nitrilase activity.
摘要:
Methods for the microbial production of para-hydroxycinnamic acid (pHCA) and cinnamic acid (CA) are provided. Microbes producing either tyrosine or phenylalanine are grown in the presence of either tyrosine ammonium lyase or phenylalanine ammonium lyase respectively where some part of the fermentation is accomplished at alkaline pH. The process results in greater yields and higher rates of para-hydroxycinnamic acid (pHCA) and cinnamic acid (CA) production as compared with fermentation exclusively at physiological pH.
摘要:
A method and media for producing bacterial cellulose under agitated culture conditions resulting in sustained production over an average of 70 hours of at least 0.1 g/liter per hour are achieved. A unique reticulated cellulose product is produced using the methods and conditions claimed, and may be converted to of a sheet characterized by substantial resistance to densification and great tensile strength when produced by sheet forming means. Acetobacter strains are identified as stable under agitated culture conditions and exhibit substantially reduced gluconic and keto-gluconic acids production.
摘要:
A method and media for producing bacterial cellulose under agitated culture conditions resulting in sustained production over an average of 70 hours of at least 0.1 g/liter per hour are achieved. A unique reticulated cellulose II product is produced using the methods and conditions claimed, and may be in the form of a sheet characterized by resistance to densification and great tensile strength when produced by sheet forming means. Also strains of Acetobacter that are stable under agitated culture conditions and that exhibit substantially reduced gluconic and keto-gluconic acids production are described.
摘要:
The present invention provides the nucleotide sequences of Acetobacter operons, cdg operons encoding genes for the biosynthesis and degradation of cyclic diguanosine monophosphate (c-di-GMP). Specifically, the nucleotide sequences and deduced amino acid sequences of 3 phosphodiesterases isozymes, 3 diguanylate cyclase isozymes, and 2 polypeptides of unidentified function are provided. Also provided for are various strains of microorganisms, including Acetobacter cells genetically manipulated so as to produce elevated and/or reduced levels of one or more cdg operon encoded proteins.
摘要:
The subject invention relates to novel compositions of neutral and/or alkaline cellulase and methods for obtaining neutral and/or alkaline cellulase compositions from Chrysosporium cultures, in particular Chrysosporium lucknowense. This invention also provides mutants and methods of generating mutants of Chrysosporium capable of producing neutral and/or alkaline cellulase. This invention also relates to the genes encoding the enzymes comprising the neutral and/or alkaline cellulase composition. In addition, this invention provides methods of culturing Chrysosporium to produce neutral and/or alkaline cellulases. The neutral and/or alkaline cellulase compositions of the subject invention can be used in a variety of processes including stone washing of clothing, detergent processes, deinking, color brightening, depilling and biobleaching of paper and pulp and treatment of waste streams. The present invention also relates to the isolation and purification of cellulase enzymes, having glucanase and cellobiohydrolase activity, and useful for stonewashing applications.
摘要:
A biocatalytic method for preparing para-hydroxystyrene from para-hydroxycinnamic acid is described. The method uses an enzyme source having para-hydroxycinnamic acid decarboxylase activity to catalyze the decarboxylation of para-hydroxycinnamic acid in a biphasic reaction medium to produce para-hydroxystyrene, which is extracted into the organic phase of the biphasic reaction medium. The method results in a high yield of para-hydroxystyrene due to the decreased exposure of the enzyme source to the inhibitory product. The product is readily recovered from the extractant, or may be chemically derivatized directly in the extractant before recovery.
摘要:
Methods for the microbial production of para-hydroxycinnamic acid (pHCA) and cinnamic acid (CA) are provided. Microbes producing either tyrosine or phenylalanine are grown in the presence of either tyrosine ammonium lyase or phenylalanine ammonium lyase respectively where some part of the fermentation is accomplished at alkaline pH. The process results in greater yields and higher rates of para-hydroxycinnamic acid (pHCA) and cinnamic acid (CA) production as compared with fermentation exclusively at physiological pH.
摘要:
This invention relates to the isolation of a novel tonB operon from Pseudomonas putida. These genes are useful to render the cells more sensitive to antibiotics, toluene, pHBA, aromatic compounds, parabenes, and aromatic amino acids after inactivation with specific mutant allels or more tolerant to these compounds after overexpression with appropriate expression vector. These findings are important in the field of medicine and biotechnology and biocatalysis. In addition a screen to identify pHBA tolerant genes is provided and strains with significant tolerance to pHBA were identified. These strains are important for pHBA production.
摘要:
Bacterial strains transformed with the pcu genes are useful for the production of para-hydroxybenzoate (PHBA). Applicant has provided the p-cresol utilizing (pcu) and tmoX gene sequences from Pseudomonas mendocina KR-1, the proteins encoded by these sequences, recombinant plasmids containing such sequences, and bacterial host cells containing such plasmids or integrated sequences. Method for the use of these materials to produce PHBA are also disclosed.