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Dual-lifetime referencing (DLR): a powerful method for on-line measurement of internal pH in carrier-bound immobilized biocatalysts.
Industrial-scale biocatalytic synthesis of fine chemicals occurs preferentially as continuous processes employing immobilized enzymes on insoluble porous carriers. Diffusional effects in these systems...Read More
Many studies show that flavonoids have a numerous biological properties, antimicrobial effects included. It is also known that rutin is able to increase the antibacterial activity of other compounds.S...Read More
Structure of a class III engineered cephalosporin acylase: comparisons with class I acylase and implications for differences in substrate specificity and catalytic activity.
The crystal structure of the wild-type form of glutaryl-7-ACA (7-aminocephalosporanic acid) acylase from Pseudomonas N176 and a double mutant of the protein (H57βS/H70βS) that displays enhanced cata...Read More
Cephalosporins currently constitute the most widely prescribed class of antibiotics and are used to treat diseases caused by both Gram-positive and Gram-negative bacteria. Cephalosporins contain a 7-a...Read More
[Expression of modified oxidase of D-aminoacids of Trigonopsis variabilis in methylotrophic yeasts Pichia pastoris].
Effective recombinant strains Pichia pastoris that produce functionally active hybrid of Trigonopsis variabilis D-aminoacids bond with chitin-connecting domain of chitinase A1 of Bacillus circulans (D...Read More
Enhancement of glutaryl-7-aminocephalosporanic acid acylase activity of gamma-glutamyltranspeptidase of Bacillus subtilis.
Semisynthetic cephalosporins, the best-selling antibiotics worldwide, are derived from 7-aminocephalosporanic acid (7-ACA). Currently, in the pharmaceutical industrie, 7-ACA is mainly produced from ce...Read More
7-Amino cephalosporanic acid (7-ACA), which is currently obtained by chemical deacylation from cephalosporin C (CPC), is a major intermediate for industrial production of β-lactam antibiotics. 7-ACA ...Read More
A single Phe54Tyr substitution improves the catalytic activity and thermostability of Trigonopsis variabilis D-amino acid oxidase.
The industrial importance of Trigonopsis variabilisd-amino acid oxidase (TvDAAO) is represented by its biocatalytic oxidative deamination of cephalosporin C (CPC) to yield glutaryl-7-aminocephalospora...Read More
A colorimetric assay for the determination of acetyl xylan esterase or cephalosporin C acetyl esterase activities using 7-amino cephalosporanic acid, cephalosporin C, or acetylated xylan as substrate
A bromothymol blue-based colorimetric assay has been devised to screen for acetyl xylan esterase or cephalosporin C (CPC) deacetylase activities using 7-amino cephalosporanic acid (7-ACA), CPC, or ace...Read More
Reusability of entrapped cells of Pseudomonas diminuta for production of 7-aminocephalosporanic acid.
Entrapped cells of P. diminuta were used for the production of 7-aminocephalosporanic acid (7-ACA), a key intermediate required for the production of most of the clinically used cephalosporin derivati...Read More
Construction of recombinant Escherichia coli D11/pMSTO and its use in enzymatic preparation of 7-aminocephalosporanic acid in one pot
The main drawback in the industrial production of 7-aminocephalosporanic acid is the accumulation of intermediate (AKA-7-ACA) and destruction of substrate (cephalosporin C) catalyzed by catalase and @...Read More
Thermal inactivation of D-amino acid oxidase from Trigonopsis variabilis occurs via three parallel paths of irreversible denaturation.
Trigonopsis variabilis D-amino acid oxidase (TvDAO) is a long-known flavoenzyme whose most important biocatalytic application is currently the industrial production of 7-amino-cephalosporanic acid (7-...Read More
Spectrophotometric assay for quantitative determination of 7-aminocephalosporanic acid from direct hydrolysis of cephalosporin C
Cephalosporins are chemically closely related to penicillins both work by inhibiting the cell wall synthesis of bacteria. The first generation cephalosporins entered the market in 1964. Second and thi...Read More
Construction and application of fusion proteins of D-amino acid oxidase and glutaryl-7-aminocephalosporanic acid acylase for direct bioconversion of cephalosporin C to 7-aminocephalosporanic acid.
Two fusion proteins of D-amino acid oxidase (DAAO) and glutaryl-7-aminocephalosporanic acid acylase (GLA) were designed to simplify the bioconversion process of cephalosporin C to 7-aminocephalosporan...Read More
Double knockout of β-lactamase and cephalosporin acetyl esterase genes from Escherichia coli reduces cephalosporin C decomposition.
The phenomenon of CPC decomposition occurs in Escherichia coli JM105/pMKC-sCPCacy during the one-step enzymatic conversion of cephalosporin C (CPC) into 7-aminocephalosporanic acid (7-ACA) by CPC acyl...Read More
7-Aminocephalosporanic acid wastewater usually contains high concentrations of ammonium (NH??-N), which is known to inhibit nitrification during biological treatment processes. Chemical precipitation ...Read More
Prospects for multivariate classification of a pharmaceutical intermediate with near-infrared spectroscopy as a process analytical technology (PAT) production control supplement
NIR spectroscopy was applied to develop a fast and reliable quality control system for a pharmaceutical substance to support information obtained through PAT surveillance of its manufacturing process....Read More
Microbial production of 7-amino-cephalosporanic acid and new generation cephalosporins (cephalothin) by different processing strategies.
The development of beta-lactam antibiotics has been a continuous battle of the design of new compounds to withstand inactivation by the ever-increasing diversity of beta-lactamases. Semisynthetic ceph...Read More
Site-specific protonation microequilibria of penicillin and cephalosporin beta-lactam core molecules
Acid-base chemistry of 6-aminopenicillanic acid (6-APA) and 7-aminocephalosporanic acid (7-ACA), the fundamental units of the two classical antibiotic families is characterised at the macroscopic and ...Read More
Single-step conversion of cephalosporin-C to 7-aminocephalosporanic acid by free and immobilized cells of Pseudomonas diminuta.
7-Aminocephalosporanic acid (7-ACA), the starting material for the production of a number of clinically used semisynthetic cephalosporins, is produced by deacylation of cephalosporin-C. The production...Read More
Batch production of deacetyl 7-aminocephalosporanic acid by immobilized cephalosporin-C deacetylase.
Bacillus subtilis SHS0133 cephalosporin-C deacetylase (CAH) overexpressed in Escherichia coli was immobilized on an anion-exchange resin, KA-890, using glutaraldehyde. The activity yield of immobilize...Read More