Procedure for enzymatic

Ac-Cys-Pro-D-Val-Cys-NH2 Typical Procedure for Enzymatic Oeavage of the S-(Phenylacetamido-methyl) Group 0 ... 

Fernandez, J., et al. (1994). An Improved Procedure for Enzymatic Digestion of Polyvinylidene Difluoride-bound Proteins for Internal Sequence Analysis, Anal. Biochem. 218 112-117. 

Figure A8.9 Procedure for the preparation of optically active a-disubstituted amino acids through stereoselective enzymatic cydisation of the N-carbamoyl derivatives.

Schneider, A. J. Willis, H. J. Sources of variation in a standardized and semi-micro procedure for serum glutamic oxalacetic transaminase. Clin. Chem. (1958), 4, 392-408. Atwood, J. G. DiCesare, J. L. Making enzymatic methods optimum for measuring compounds with a kinetic analyzer. Clin. Chem. (1975), n, 1263-1269. 

The file Is used routinely In the laboratory at the National Institutes of Health In an attempt to explain abnormal test results The resident physicians affiliated with the Clinical Chemistry Service discuss the results with the patient-care physicians and determine If the results were due to the patient s clinical state or to a drug effect This close monitoring of test results has led to recognition of deficiencies In what Is believed are specific enzymatic procedures for the measurement of glucose and uric acid Likewise, the gualac procedure for occult blood In feces was found to yield false negative results under certain circumstances This has prompted the development of a more specific procedure (Jaffe et al unpublished) ... 

Experimental procedure for the enzymatic esterification of oleic acid with... 

Chemical, thermal, or enzymatic treatments are required to obtain analysable samples. Two typical methods used to achieve the hydrolysis of peptidic bonds are enzymatic and chemical catalysis [73]. The reaction times for enzymatic hydrolysis are long and typically lie in the range of 4 8 h [47]. Additionally, they demand purification procedures to get rid of the excess enzyme that could interfere in the protein identification. Due to these drawbacks, this method of hydrolysis finds limited use in the conservation science field. 

Gorun, V., Proinov, I., Baltescu, V., Balaban, G. and Barzu, O. (1978). Modified Ellman procedure for assay of cholinesterases in crude enzymatic preparations. Analytical Biochemistry 86 324-326. 

Sato H (2002) Enzymatic procedure for site-specific pegylation of proteins. Adv Drug Deliv Rev 54 487-504... 

Regardless of the type of enzymatic labeling used, it is important that the label be incorporated into the nucleoside triphosphates or primers in a way that does not affect enzyme recognition and activity. Thus, every enzymatic labeling procedure for modifying RNA or DNA probes must start with chemical derivatization of individual nucleotides. Of the many chemical procedures that can be used to modify a nucleoside triphosphate monomer, there are only a few that will result in a derivative still able to be enzymatically added to an existing oligonucleotide strand. 

Acyl nitroso compounds (3, Scheme 7.2) contain a nitroso group (-N=0) directly attached to a carbonyl carbon. Oxidation of an N-acyl hydroxylamine derivative provides the most direct method for the preparation of acyl C-nitroso compounds [10]. Treatment of hydroxamic acids, N-hydroxy carbamates or N-hydroxyureas with sodium periodate or tetra-alkyl ammonium periodate salts results in the formation of the corresponding acyl nitroso species (Scheme 7.2) [11-14]. Other oxidants including the Dess-Martin periodinane and both ruthenium (II) and iridium (I) based species efficiently convert N-acyl hydroxylamines to the corresponding acyl nitroso compounds [15-18]. The Swern oxidation also provides a useful alternative procedure for the oxidative preparation of acyl nitroso species [19]. Horseradish peroxidase (HRP) catalyzed oxidation of N-hydroxyurea with hydrogen peroxide forms an acyl nitroso species, which can be trapped with 1, 3-cyclohexanone, giving evidence of the formation of these species with enzymatic oxidants [20]. 

Polymerase chain reaction An in vitro method for enzymatically synthesizing and amplifying defined sequences of DNA in molecular biology. Can be used for improving DNA-based diagnostic procedures for identifying unknown BW agents. 

An enzymatic procedure for the synthesis of 142, starting from 135, has been described by Bhalerao et al. <1994T4019>. The product 142 has been synthesized by the use of laccase enzyme under mild conditions (aqueous acetonitrile, rt, 12 h) in 90% yield. 

Van Langen, L.M., yan Rantwijk, F. and Sheldon, R.A., Enzymatic hydrocyanation of a sterically hindered aldehyde. Optimization of a chemoenzymatic procedure for (R)-2-chloro-mandelic acid. Org. Proc. Res. Dev., 2003, 7, 828-831. 

This is a simple procedure for the enzymatic resolution of a secondary amine. The acylating agent can be modified by altering the substitution on the phenol ring. This tuning of the reactivity and selectivity should allow other amines to be resolved using a similar approach. 

The procedure shows that it is feasible to combine racemization with the kinetic resolution process (hence the DKR) of R,S)- ethoxyethyl ibuprofen ester. The chemical synthesis of the ester can be applied to any esters, as it is a common procedure. The immobilized lipase preparation procedure can also be used with any enzymes or support of choice. However, the enzyme loading will need to be optimized first. The procedures for the enzymatic kinetic resolution and DKR will need to be adjusted accordingly with different esters. Through this method, the enantiopurity of (5)-ibuprofen was found to be 99.4 % and the conversion was 85 %. It was demonstrated through our work that the synthesis of (5)-ibuprofen via DKR is highly dependent on the suitability of the reaction medium between enzymatic kinetic resolution and the racemization process. This is because the compatibility between both processes is crucial for the success of the DKR. The choice of base catalyst will vary from one reaction to another, but the basic procedures used in this work can be applied. DKRs of other profens have been reported by Lin and Tsai and Chen et al. ... 

Experimental samples are mainly derived from tissue culture cells, laboratory animals, or human tissues collected from hospitals after surgical biopsies and autopsies. With human and animal tissue specimens, it is important to arrest metabolic processes within 5-10 min of collection in order to preserve mRNAs from degradation by internal enzymatic reactions (26,27). Most hospitals use 10% buffered formalin as a tissue fixative. Subsequently, each tissue slice is trapped in a paraffin block. Series of 4-5-pm-thick sections are cut and mounted on silanated slides. Formalin-fixed archival tissues have been successfully used in in situ PCR and in situ hybridization protocols (28-32). However, the procedure for RNA protection is not always followed. It is often difficult to alter or control the routine procedures of hospitals for the required protection of mRNAs in surgically removed human tissues. 

Favretto et al. [33] proposed a procedure for the analysis of BUP and nor BUP based on RP-HPLC conpled with ion trap MS nsing an ESI ion source. The use of the ion trap allowed to obtain intense prodnct ions nnder MS-MS conditions, thus achieving better selectivity of detection with respect to LC-ESI-MS-MS methods with triple qnadrupoles where effective fragmentation in the collision cell was fonnd difficnlt to obtain. However, this method does not inclnde phase II metabolites of BUP, which can be only indirectly determined after enzymatic hydrolysis. 

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