The major acid phosphatase [EC 3.1.3.2J isozyme secreted by maize endosperm cultures was purified from concentrated culture filtrates by (NH4)2S04 fractionation and chromatography on columns of diethylaminolethylSephadex A-25, concanavalin A-Sepharose, and Sephacryl S200. The native and subunit M, value's for the purified phosphatase were 29000 and 31500, respectively. The purified enzyme conta...

Nitronyl nitroxides are capable of preventing cells, tissues, and organs from radical-induced damage through scavenging NO˙, ˙O(2)(-) and ˙OH. In order to explore the conversions of nitronyl nitroxides in biological systems with and without NO˙, HPLC-MS aided PC12 cell systems were developed, and the conversions of 2-(3'-nitrophenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl -3-oxide (3-nitro-PTIO)...

Recent studies have shown that compounds based on a (2-nitrophenyl)methanol scaffold are promising inhibitors of PqsD, a key enzyme of signal molecule biosynthesis in the cell-to-cell communication of Pseudomonas aeruginosa. The most promising molecule displayed anti-biofilm activity and a tight-binding mode of action. Herein, we report on the convenient synthesis and biochemical evaluation of ...

In order to improve the activities of mycelium-bound ester hydrolases of Aspergillus oryzae Cs007, the main production conditions were investigated. The activities of the ester hydrolases were simultaneously determined by titration assay and spectrophotometric assay methods, using olive oil and p-nitrophenyl esters as substrates, respectively. The optimum carbon source and nitrogen source were ...

1. A new and convenient synthesis of p-nitrophenyl diazoacetate has been devised from p-nitrophenyl chloroformate and diazomethane. 2. p-Nitrophenyl diazoacetate reacts stoichiometrically with chymotrypsin to yield diazoacetyl chymotrypsin. 3. Photolysis of the diazoacetyl enzyme with light of wave length greater than 320 rnp yields a mixture of (a) glycolic acid and regenerated chymotrypsin an...

An aryl beta-xylosidase was purified to homogeneity from an Escherichia coli strain containing a recombinant plasmid carrying a beta-xylosidase (EC 3.2.1.37) gene from the extremely thermophilic anaerobic bacterium isolate Tp8T6.3.3.1 ('Caldocellum saccharolyticum'). It has a pI of 4.3 and shows optimal activity at pH 5.7. The enzyme is highly specific, acting on o- and p-nitrophenyl beta-D-xyl...

Fourteen new thiazolyl hydrazone derivatives were synthesized and evaluated for their anticandidal activity using a broth microdilution assay. Among the synthesized compounds, 2-[2-((5-(4-chloro-2-nitrophenyl)furan-2-yl)methylene)hydrazinyl]-4-(4-fluorophenyl)thiazole and 2-[2-((5-(4-chloro-2-nitrophenyl)furan-2-yl)methylene) hydrazinyl]-4-(4-methoxyphenyl)thiazole were found to be the most eff...

The reduction of oxygen on gold electrodeposited on an organic template has been investigated. The template consisted of reduced 4-nitrophenyl groups attached to glassy carbon (GC) by the electrochemical reduction of the corresponding diazonium compound. The electrode modified by this Au nanostructured film shows electrocatalytic properties for the oxygen reduction reaction (ORR) different from...

p-Nitrophenyl and cholesteryl-N-alkyl carbamates are good inhibitors of porcine pancreatic cholesterol esterase-catalyzed hydrolysis of p-nitrophenyl butyrate. p-Nitrophenyl-N-butyl and N-octyl carbamates (compounds 1 and 2, respectively) are potent active site-directed irreversible inhibitors of this enzyme. The inhibition of cholesterol esterase by compound 1 or 2 shows saturation kinetics wi...

cY-Chymotrypsin rapidly catalyzes the release of p-nitrophenol from carbobenzoxy-n-tyrosine p-nitrophenyl ester and the reaction has been made the basis of a spectrophotometric assay requiring only millimicrogram quantities of the crystalline enzyme (1). Other nitrophenyl esters, e.g. of acetic acid (2), hydrocinnamic acid (3), and carbobenzoxyglycine (4) are also hydrolyzed by chymotrypsin des...