Enzymes enzymic hydrolysis

Somatostatin is a tetradecapeptide of the hypothalamus that inhibits the release of pituitary growth hormone Its ammo acid sequence has been determined by a combination of Edman degradations and enzymic hydrolysis expenments On the basis of the following data deduce the pnmary structure of somatostatin... 

Fish proteia coaceatrates vary widely ia fuactioaal characteristics, ranging from those having high proteia coateat and low water solubiUty, to those having lower proteia coateats but improved water solubiUty. Attempts have beea made to improve fuactioaal properties of fish proteia by enzyme hydrolysis (141), or by modificatioa of the myofibrillar proteia by succiaylatioa (142). 

Cane sugar is metabolized rapidly, after initial enzyme hydrolysis to glucose and fmctose. As a carbohydrate, it yields 16.5 kj/g (3.94 kcal/g). 

Olestra is prepared by a solvenfless transesterification process in which sucrose is treated with methyl ester of fatty acids in the presence of sodium methoxide between 100—180°C for 14 hours (68). The manufacturing process involves removal of the unreacted fatty acid esters by enzymic hydrolysis... 

M. Mandels and E.T. Reese, in Advances in Enzymic Hydrolysis of Celltdose and Related Materials, ed. E. T. Reese, Pergamon, Oxford, 1963, pp. 115-157. 

Leukotriene B4, formed by enzymic hydrolysis of LTA4, is chemotactic for macrophages and neutrophils at concentrations as low as 1 ng/ml. The stereochemistry of the conjugated triene subunit was established by synthesis which also made LTB4 available in quantity for biological research. 

It was of interest to determine whether glycosides of 6-deoxy-D-xylo-hex-5-enopyranose were susceptible to enzyme hydrolysis by / -glucosi-dase. Since aromatic glucosides are hydrolyzed by this enzyme at a much faster rate than aliphatic glycosides, phenyl 6-deoxy-/ -D-rt/Zo-hex-5-enopyranoside (18) was prepared (20). Phenyl / -D-glucopyranoside was converted to the 6-tosylate by selective esterification and then, by conventional procedures, transformed to phenyl 2,3,4-tri-0-acetyl-6-deoxy-... 

Rate Constants and Activation Parameters for the Non-enzymic Hydrolysis of D-Glucopyranoside at pH 5... 

Catalytic Constants and Activation Parameters for the Enzymic Hydrolysis of /i-D-Glucopyranosides ... 

Enzyme hydrolysis of sample decarboxylation of trichloroacetic acid headspace gas analyzed... 

Hydrolysis of RNA by alkali or pancreatic RNase leads initially to fragments which terminate in 2, 3 -cyclic phosphodiesters. Micrococcal nuclease, on the other hand, gives rise to fragments terminating in 3 -phos-phomonoester groups which facilitate their isolation, and this enzymic hydrolysis has been used to prepare 3 -ribodinucleotides. ... 

The conformations of L-adenylyl-(3 5 )-L-adenosine (28) and L-adenylyl-(2 -> 5 )-L-adenosine (29), as deduced from circular dichroic spectra, are different from the corresponding DD-dinucleotides. < The n.m.r. and u.v. absorption spectra of (28) and (29) are the same as the DD-dimers and their chromatographic and electrophoretic properties appear identical. While (28) and (29) are resistant to enzymic hydrolysis they form complexes with polyU. 

A method for the direct spectrophotometric determination of dinucleoside monophosphates has been developed which relies on changes in u.v. absorbance after enzymic hydrolysis. - Hydrolytic fission of the dinucleoside monophosphate with a phosphodiesterase causes a change in the u.v. absorbance of the solution allowing the 5 -nucleoside to be estimated. Addition of a phosphomonoesterase to the hydrolysate causes a further change in u.v. absorbance, allowing the 3-nucleoside to be estimated. 

Fig. 8. Schematic for the micrococcal nuclease attack to (a) breathing ds-DNA, (b) dista-mycin-bound DNA, and (c) Zn2+-cyclen derivative-bound DNA. Arrows and dashed arrows, respectively, indicate successful and failed enzyme hydrolysis. Reproduced with permission from Ref. (37). Copyright 1999, American Chemical Society.

Mazaleyrat, J.-P. Reboud-Ravaux, M. Wakselman, M. Synthesis and enzymic hydrolysis of cyclic peptides containing an anthranilic acid residue. Int. J. Peptide Protein Res. 1987, 30, 622-633. 

Reboud-Ravaux, M. Convert, O. Mazaleyrat, J.-P. Wakselman, M. Structural factors in the enzymic hydrolysis of cyclopeptides containing an ortho- or meta-amino benzoic acid residue. Bull. Soc. Chim. Fr. 1988, 267-271. 

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