Isoamylases

Since pancreatic and salivary isoamylases differ from one... 

Several variations on these production methods also exist, such as the use of immobilized CGTase (2i, 22), continuous ultrafiltration 23) and the use of isoamylase to increase CD yield. Variations of purification methods include the addition of glucoamylase to degrade non-CD starch hydrolysates to simply separation and the use of various S3mthetic ion exchange resins in chromatographic separations 24-26) and acuity columns (27),... 

Isoamylase [9067-73-6] (glycogen-6-glucanohydrolase) and pullulanase [9012-47-9] (pullulan-6-glucanohydrolase) hydrolyzes a-l,6-glucosidic bonds of starch. When amylopectin is treated with a pullulanase, linear amylose fragments are obtained. Using a heat- and acid-stable pullulanase in combination with saccharifying enzymes makes the starch conversion reactions more efficient (71). 

W5. Warshaw, A. L., and Lee, K. H., Aging changes of pancreatic isoamylases and the appearance of old amylase in the serum of patients with pancreatic pseudocysts. Gastroenterology 79, 1246-1251 (1980). 

Takeda et al.249 analyzed the branched products made in vitro from amylose by the BE isoforms Isoamylase was used to debranch the products of each reaction. BEIIa and BEIIb were very similar in their affinity for amylose and the size of chain transferred. 

As noted in Section 4.3 (see also Chapter 3), a sul mutation in maize that causes a deficiency of isoamylase, an enzyme normally considered to be mainly involved in starch degradation in plants and in C. reinhadtii, results in accumulation of a water-soluble polysaccharide, phytoglycogen, instead of starch.45 19,291 In C. reinhardtii, the mutation results in complete loss of starch, but in higher plants, the lower amount of amylopectin seen in the mutant plant may be related to the severity of the enzyme deficiency.292,293... 

Figure 6.5 Gel permeation chromatogram of isoamylase-treated potato amylose on Toyopearl HW-75F. Potato amylose (50 mg in 5 ml ) was incubated at 45°C with 5.5 U of Pseudomonas isoamylase in 20 mM acetate buffer (pH 3.5) for 2.5 h. An aliquot (1 ml.) was applied to the column — and , carbohydrate concentration and beta-amylolysis limit, respectively, of the isoamylase-treated amylose ., carbohydrate...

Figure 6.9 Gel-permeation hplc of isoamylase-debranched (a) potato and (b) waxy rice amylopectin.263...

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