Enzyme amylolytic

The effectiveness of proteolytic, amylolytic, and lipolytic detergent enzymes is based on enzymatic hydrolysis of peptide, glucosidic, or ester linkages. The mainstay of the market has been the protease types. 

Xylan is an essential constituent of hardwoods, softwoods, and annual plants. In enzymatic processing of lignocellulosic biomass, xylanolytic enzymes may be used either individually, in selected mixtures for specific effects on only the xylan component of the raw material, or in mixtures with cellulolytic, pectinolytic or amylolytic enzymes. 

A great advantage of spectrophotometric assays is that they can be carried out in microtiter plates or as filter paper assays, thus allowing a high sample throughput coupled with small sample volumes. Such systems were used for example for the screening of epoxide hydrolases [34]. A classical example of activity tests is for amylolytic enzymes where starch agar plates are stained with iodine after a certain reaction time. The radius of clear spots is a measure of the reaction rate [35]. 

Bromelain (from pineapple) has applications in milk clotting. Malt extract from barley has amylolytic enzymes used in beer brewing. 

Berry, C.S. 1986. Resistant starch Formation and measurement of starch that survives exhaustive digestion with amylolytic enzymes during the determination of dietary fibre. J. Cereal Sci. 4 301-314. 

Four major enzyme groups are secreted lipolytic, proteolytic, amylolytic, and nucleic acid splitting enzymes. These pancreatic enzymes, some of which are secreted in multipile forms, possess specificities complementary to die intestinal membrane-bound enzymes (Tabic 1). Fresh, uncontsnkinated pancreatic juice is without proteolytic activity because these enzymes am in the form of inactive zymogens. An important fraction of the calcium in pancreatic juice accompanies the enzymes, especially ct-amylase. Human pancreatic juice is moat dose to that of the pig, with high proportions of lipase and a-amylase in comparison with other mammals [1]. Therefore, pig pancreas extract, pancreatin, has up to now been die oreferred enzvme source for therapeutic tuncreas substitution. 

Pancreas powder is prepared from the fresh or frozen pancreases of mammals. It contains various enzymes having proteolytic, lipolytic, and amylolytic activities. One milligram of oancreas uowder contains not leas than 1.0 Eumrean... 

Horvathova, V., Janecek, S., and Sturdik, E. 2001. Amylolytic enzymes Molecular aspects of their properties. Gen Physiol Biophys 20 7-32. 

Amino acid sequence relationships between that of branching enzyme (BE) and amy-lolytic enzymes, such as a-amylase, pullulanase, glucosyltransferase and cyclodextrin glucanotransferase, especially at those amino acids believed to be contacts between the substrate and the amylase family enzymes, were first reported by Romeo et al.283 Baba et al.284 reported that there was a marked conservation in the amino acid sequence of the four catalytic regions of amylolytic enzymes in maize endosperm BEI. As shown in Table 4.12, four regions that putatively constitute the catalytic... 

As indicated in Table 4.12, four regions which constitute the catalytic regions of amylolytic enzymes are conserved in the starch-branching isoenzymes of maize endosperm, rice seed and potato tuber, and the glycogen-branching enzymes of E. coli.286,281 It would be of interest to know whether the seven highly conserved amino acid residues of the a-amylase family listed in bold letters in Table 4.12 are also functional in branching enzyme catalysis. Further experiments, such as chemical modification and analysis of the three-dimensional structure of the BEs, would be needed to determine the nature of its catalytic residues and mechanism. 

Primary, secondary and tertiary structures of amylolytic enzymes from a wide variety of sources and functions (the a-amylases, bacterial cyclomaltodextrin glucanosyltrans-ferases, isoamylases and starch-branching enzymes) have been found to be closely related, and have been placed into the so-called structural a-amylase family.176,177 These enzymes have been studied with regard to the number, structure, organization and function of domains.178... 

A few chimeric enzymes have been constructed by adding one or more domains from one amylolytic enzyme to another. Some of these chimeric enzymes have been studied in regard to the secretion of the enzyme,187 substrate specificity188 and product specificity.189 A starch binding domain from a Bacillus sp. cyclomaltodextrin glucanosyltransferase was fused with B. subtilis a-amylase, and an a-amylase was... 

An a-D-glucopyranan from fruit bodies of Lentinus edodes is slightly branched, with (1— 3) and (1—>4) linkages in the ratio of 5.3 1. It is partially degraded by amylolytic enzymes, and it was concluded that the (1—>4) linkages are concentrated in regions not far from nonreducing ends.33... 

The commercial importance of amylolytic enzymes is rapidly increasing. These enzymes catalyze the hydrolytic reactions of amylose (unbranched starch) and amylopectin (branched starch). Amylases, according to their difference in modes of action, can be divided into ... 

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