Bacillus subtilis amylase

The substrate specifity of Bacillus subtilis amylase was studied by Robyt and French (11) by using maltodextrins as well. These authors employed, among others, maltooctaose as a substrate for the investigation of Bacillus polymixa... 

Acetylation of a tyrosyl residue in Bacillus subtilis amylase led to partial loss of the enzymic activity towards a series of malto-oligosaccharides, indicating that a tyrosyl residue located near the catalytic site is involved in the productive binding of substrates. The difference spectrum of a tryptophanyl residue in Bacillus subtilis a-amylase was significantly decreased following treatment with... 

Fig. 1. Enzymatic liquefaction processes (9). Alpha-S is the a-amylase from bacillus subtilis alpha-L/ST are a-amylases from B. licheniformis oi B.

Bacterial amylase Bacillus subtilis Modified starch, sizing paper... 

Isolation of a-amylase and protease from Bacillus subtilis fermentation broth [20]... 

Aldolase (muscle and liver)[4] Aminopeptidase[5] a-Amylase (Bacillus subtilis)[6]... 

Fischer, brilliant results were achieved, and in succession the a-amylases of pig pancreas, of Bacillus subtilis, of human saliva, of human pancreas, and of Aspergillus oryzae, and the /3-amylase of malt, were successfully crystallized. Important biological deductions were gained from this study whereas the amylases of human pancreas and saliva cannot be distinguished from one another, amylases from pig pancreas and from human pancreas are different. These differences are manifested in molecular weight, crystalline forms, electrophoretic mobility, and influence of the pH on the activity however, all the amylases have the same specific biochemical action. The identity of the enzymes seems to be dependent on the species and not on the organ. Interest in biologically active proteins led Meyer to a study of the protein hormones, a field in which he was very active at the time of his death. 

Enz5mies Proteases Amylases Cellulases Various Bacilli, e.g. Bacillus licheniformis Bacillus subtilis, Aspergillus oryzae Trichoderma viride, Penicillium pinophilum... 

Several amylases have been partially sequenced (42-45). For example, a-amylase from Bacillus subtilis, which is composed of two subunits of 24,000 molecular weight each, has an amino terminal sequence as shown in Table V (42). Perhaps fortuitously, the sequence of residues 8 through 12 resembles residues 14 through 18 in xylanase A, in that a polar residue is surrounded by four aromatic residues. 

In pine, it was found that Bacillus polymyxa was the major species involved (45, 55), whereas, in spruce the major species were Bacillus subtilis and Flavobacterium pectinovorum (49). In another study (53), Clostridium omelianskii was identified as the species attacking softwoods. In all studies, it was found that the bacterial attack on the pit membranes was the reason for increased permeability of the wood. Furthermore, it was shown by Fogarty and Ward (49) that bacteria degraded the pit membranes by excreting the enzymes amylase xylanase, and pectinase. A typical sapwood pit membrane that has been attacked by bacteria is shown in Figure 2. As can be seen, the torus is severely degraded and has well defined openings. 

Among hydrolases with allergenic properties used in the food industry there are a-amylases, amyloglucosidases, glucoamylases, cellulases, hemicellulases, pecti-nases, lipoxygenases, and xylanases (Bindslev-Jensen et al. 2006, Cullinan et al. 1997, Houba et al. 1997, Kanerva and Vanhanen 1999, 2001, Scheibe et al. 2001). Most of these enzymes are synthesized by A. otyzae fungi or Bacillus subtilis bacteria. 

The organism that elaborates this a-amylase was originally called Bacillus subtilis. It was reclassified as Bacillus amyloliquefaciens in 1967.8... 

Bacillus shigae, antigens, II, 166 Bacillus subtilis, V, 48 amylase of, V, 265... 

Nishimura, T., Kometani, T., Takii, H.,Terada, Y., and Okada, S. 1994. Purification and some properties of a-amylase from Bacillus subtilis X-23 that glucosylates phenolic compounds such as hydroquinone. /. Ferment. Bioeng., 78, 31-36. 

In 1890, the Japanese chemist Jokichi Takamine had introduced a fermentation process in the United States by which an enzyme blend was produced. This takadias-tase catalyzed starch and protein hydrolysis. Some years later in 1913, Boidin and Effront discovered the bacillus subtilis" that produced an a-amylase stable under heat. This enzyme was used to desize cloth and later in the sugar fermentation process. 

In the brewing industry, there is a development toward substitution of malt with unmalted barley and amylase, by use of glu-canase and protease of microbial origin. The neutral protease from Bacillus amyloliquefaciens and the thermostable neutral protease Bacillus subtilis var. thermoproteolyticus have been used by brewers successfully to hydrolyze barley proteins into amino acids and peptides. 

Carbohydrase (Bacillus subtilis containing a Bacillus mega-terium a-amylase gene) Produced as an off white to brown, amorphous powder or liquid by controlled fermentation using the modified Bacillus subtilis. Soluble in water (the solution is usually light yellow to dark brown), but practically insoluble in alcohol, in chloroform, and in ether. Major active principle a-amylase. Typical applications used in the preparation of starch syrups, alcohol, beer, and dextrose. 

Maltogenic Amylase carbohydrase Bacillus subtilis 1,4-a-D-glucan 3.2.1.133... 

Application and Principle This procedure is used to determine the a-amylase activity, expressed as bacterial amylase units (BAU), of enzyme preparations derived from Bacillus subtilis var., Bacillus licheniformis var., and Bacillus stearoth-ermophilus. It is not applicable to products that contain 13-amylase. The assay is based on the time required to obtain a standard degree of hydrolysis of a starch solution at 30° 0.1°. The degree of hydrolysis is determined by comparing the iodine color of the hydrolysate with that of a standard. 

Application and Principle This procedure is used to determine maltogenic amylase activity in preparations derived from Bacillus subtilis containing a Bacillus stearothermophilus amylase gene. The test is based on a 30-min hydrolysis of malto-triose under controlled conditions and measurement of the glucose formed by high-performance liquid chromatography (HPLC). 

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