Pseudomonas isoamylase

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...

A starch-debranching isoamylase, obtained from sugary 1 (sul) maize, has been cloned by James et al.70 and found to have 32% sequence identity with Pseudomonas isoamylase. Other isoamylases or starch debranching enzymes have been isolated from Cytophaga sp.,71 Streptomyces sp.,72 Flavobacterium sp.,73 a yeast, Lipomyces kononenkoae,74 potato tubers,75 B. circulans76 and an alkaline isoamylase with a pH optimum of 9 from an alkalophilic Bacillus sp.77... 

Harada, T., Misaki, A., Akai, H., Yokobayashi, K. and Sugimoto, K., 1972, Characterisation of Pseudomonas isoamylase by its actions on amylopectin and glycogen Comparison with Aerobacter pullulanase, Biochim. Biophys. Acta, 268 497. 

Maltotriose is effective as a side-chain donor and acceptor in the presence of a Pseudomonas isoamylase and gives a set of 6- -a-malto-... 

Pseudomonas species isoamylase has been shown to have little action on starch granules. Pseudomonas isoamylase has been shown to hydrolyse (1 6)-... 

The amounts of A chains, vhich link to a Ba chain, were analyzed by the following procedures. Here, Ba chains are defined as B chains which carry at least one A chain and the rest of the B chains are defined as Bb chains. Amylopectin is first processed into B-limit dextrin (B-LD) with sweet potato B-amylase, then with Pseudomonas isoamylase, and finally again with g-amylase (2nd B-amylolysis), successively. A chains are trimroed into roaltosyl or maltotriosyl residues depending on the even or odd numbers of the chain length... 

Possible synergistic effects resulting from the actions of a Pseudomonas isoamylase and Aspergillus awamori glucoamylases have been investigated. ... 

Isoamylases that exclusively hydrolyze the q -(1—>6) branch linkages of starch were first recognized in plants and first isolated from broad beans [92]. A bacterial isoamylase was obtained from the culturing of Pseudomonas amyloderamosa [93,94,95,96] and has found wide use in studying the structure of amylopectin and related polysaccharides [97]. 

I, 6-branching points in substrates like amylopectin. Isoamylase has higher affinity to large branched polysaccharides. The enzyme is very rare among microorganisms and has been detected in Pseudomonas amyloderamosa and Cytophaga sp.[29> 30). 

Isoamylase branched polysaccharides [endoacting a-1,6] linear polysaccharides Pseudomonas amyloderamosa Flavobacterium odorratum... 

Sugimoto, T, A Amemura and T Harada (1974). Formations of extracellular isoamylase and intracellular alpha-glucosidase and amylase(s) by Pseudomonas SB15 and a mutant strain. Applied Microbiology, 28, 336-339. 

The use of amylose gel cross-linked by epichlorohydrin for affinity chromatography of extracellular isoamylase of Pseudomonas amyloderamosa has been studied. The isoamylase was adsorbed well on the amylose gel and was eluted specifically with maltodextrin. The eluted enzyme was precipitated with ammonium sulphate to remove maltodextrin, and then the solution of the precipitate was dialysed and concentrated by vacuum filtration. By this procedure 96 mg of the enzyme were purified to homogeneity from 20 1 of culture broth in about 70% yield. 

Amylose cross-linked with epichlorohydrin has been used for the affinity chromatographic purification of the extracellular isoamylase of Pseudomonas... 

The isoamylase enzyme preparation that was evaluated is obtained by pure culture fermentation of Pseudomonas amyloderamosa. The Committee reviewed toxicological data on this enzyme at its fifty-fifth meeting (Annex 1, reference 149) as part of the safety assessment of trehalose. The Committee at that meeting concluded that the available data on isoamylase (i.e. a study of acute toxicity, a 13-week study of toxicity and a bacterial mutagenicity assay) did not raise any safety concern. 

Haddouk, H. (2001) Isoamylase from Pseudomonas amyloderamosa—In vitro mammalian chromosome aberration test in cultured human lymphocytes. Unpublished report No. 20147 MLH from Centre International de Toxicologie, Evreux, France. Submitted to WHO by Bioresco Ltd, Basel, Switzerland. 

An isoamylase from a Pseudomonas sp. has a synergistic effect on the gluco-amylase of Aspergillus awamori var. kawachi ... 

Epichlorohydrin-crosslinked amylose has been used as an affinity matrix for the isolation of the extracellular isoamylase of Pseudomonas amyloderamosa and for the purification of the periplasmic maltose-binding protein of Escherichia coli. ... 

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