Pseudomonas amyloderamosa isoamylase

The structures of the shghtly branched amyloses have been determined using pullulanase and Pseudomonas amyloderamosa isoamylase [30-32]. The size distribution of the branch chains were determined by hydrolysis of the a-1 6 branch... 

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... 

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. 

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 Unpublished report No. 20147 MLH from Centre International de Toxicologie, Evreux, France.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. 

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. ... 

Pseudomonas amyloderamosa elaborates an isoamylase that specifically hydrolyzes the a-1 -> 6 branch linkages of starch [16-20]. Another enzyme that also will hydrolyze the a-1 6 branch linkages of starch is pullulanase, which is elaborated by a strain of A. aerogenes [20]. This enzyme is a hydrolase that specifically hydrolyzes the a-1 6 linkages of the linear polysaccharide, pullulan... 

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