Enzyme digestible

An enzyme digest is the term applied to a process whereby a peptide or protein is mixed with a selected enzyme under favorable conditions to allow reaction to occur. The enzyme splits the peptide or protein into smaller units that are easier to identify. 

Tandem mass spectrometry (MS/MS) produces precise structural or sequence information by selective and specific induced fragmentation on samples up to several thousand Daltons. For samples of greater molecular mass than this, an enzyme digest will usually produce several peptides of molecular mass suitable for sequencing by mass spectrometry. The smaller sequences can be used to deduce the sequence of the whole protein. 

Casein hydrolyzates are produced from dried casein. With appropriate heat treatment and the addition of alkaHes and enzymes, digestion proceeds. FoUowing pasteurization, evaporation (qv), and spray drying, a dried product of 2—4% is obtained. Many so-called nondairy products such as coffee cream, topping, and icings utilize caseinates (see Dairy SUBSTITUTES). In addition to fulfilling a nutritional role, the caseinates impart creaminess, firmness, smoothness, and consistency of products. Imitation meats and soups use caseinates as an extender and to improve moistness and smoothness. 

Confirmation of Amino Acid Sequence Using the Analysis of LC-MS Data from an Enzyme Digest of a Protein 152... 

Amino Acid Sequencing of Polypeptides Generated by Enzyme Digestion Using MS-MS 166... 

Enzyme digestion The treating of a protein with a proteolytic enzyme to form a number of smaller peptides which may then be sequenced. 

Peptide mapping The process of considering the amino acid sequence information from peptides obtained by enzyme digestion in an attempt to derive the (amino acid) sequence of the parent protein. 

C]methylated glycophorin work in this laboratory indicates that it results from head-to-head dimerization of glycophorin molecules. This phenomenon could be studied by isolation of the cross-linked product (intact, or enzymically digested). 

E. Physical Methods and Analytical Techniques.—Nucleotide maps of enzymic digests of DNA have been obtained using the same ionophoretic techniques as have been developed for RNA digests. Pancreatic DNase and Neurospora crassa endonuclease produce very similar maps with E. coli DNA but this technique still awaits the discovery of specific DNases. 

Anti-complementary activity of enzymic digestion products from the pectins of Angelica acutiloba... 

Pectins were extracted from isolated cell walls of 5-week-old wheat plants using different methods. Enzymic digestions of the cell walls involved pectinases such as a commercial pectolayse or recombinant endopolygalacturonase [Maness Mort, 1989]. Chemical extractions involved the chelating agent imidazole [Mort et al., 1991] or solvolysis with anhydrous HF at 0 °C in a closed teflon line [Mort et al., 1989] followed by imidazole extraction. 

The reversibility of dA alkylation by QM3 creates both problems and opportunities. For example, an accurate profile of products formed by initial exposure of DNA to QMs may not be easily determined since labile products such as the N1 adduct of dA would not persist through the typical procedures of enzyme digestion and analysis of the subsequent deoxynucleoside products by reverse phase HPLC. Thus, the full extent of DNA alkylation by QMs may be severely underestimated. 

Opiate receptor binding activity has been recognized in coffee. It is ether extractable and not modifiable by enzymic digestion with papain it has a molecular weight in the range of 1,000 to 3,500.70... 

Gastric Retention of Enzyme-Digestible Hydrogels in the Canine Stomach under Fasted and Fed Conditions... 

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