Bacillus polymyxa

Bacillus fragilis Bacillus lichemformis Bacillus megaterium Bacillus polymyxa Bacillus sphaericus... 

The fermentation medium was inoculated with Bacillus polymyxa prepared as follows ... 

A culture of Bacillus polymyxa in a tube with Trypticase soybean broth was incubated overnight at 25°C. 5 ml of this culture was transferred to 100 ml of the tank medium in a 500 ml Erlenmeyer flask which was incubated for 48 hours at room temperature. This 100 ml culture served as inoculum for one tank. During the course of fermentation the medium was aerated at the rate of 0.3 volume of air per volume of mash per minute. The temperature was maintained at about 27 C. Samples of mash were taken every 8 hours in order to determine pH and the presence of contaminants and spores. After 88 hours of fermentation the pH was about 6.3 and an assay using Escherichia coll showed the presence of 1,200 units of polymyxin per cubic centimeter. The polymyxin was extracted and purified by removing the mycelia, adsorbing the active principle on charcoal and eluting with acidic methanol. 

Aspergillus sclerotiorum Huber Oxamniquina Bacillus lentus Dasoximatasona Diflucortolona valarata Bacillus polymyxa Polymyxin... 

Polymyxin B Bacillus polymyxa Gram-negative bacteria Cell membrane... 

Cyclopolypeptide antibiotic from cultures of Bacillus polymyxa. 

Figure 4.4 Surface structure of a spore of Bacillus polymyxa. From left to right side view same rotated a quarter turn from right to left same rotated a further quarter turn view, of a pole.

The hydroxyl groups at C-2 and C-3 are not essential for the catalytic reaction. McNicol and Baker233 showed that the endopectate lyases of Bacillus sphaericus and Bacillus polymyxa degrade the Vi antigen, the bacterial-surface polysaccharide containing a-D-(1 — 4)-linked residues of 2-acetamido-3-0-acetyl-2-deoxy-D-galac-topyranuronate, in the same way as its O-deacetylated derivative and D-galacturonan. 

For endopectate lyases, the rate of cleavage of glycosidic bonds and the affinity of the enzyme for the substrate depend on the chain length,240,241 as with endo-D-galacturonanase. The frequency of splitting of bonds 2 and 3 in tetra(D-galactosiduronic acid) is different. Endopectate lyase of Bacillus polymyxa splits240 bond 3 1.4 times faster than bond 2. 

Action pattern A was observed with extracellular, endopectate lyase of Bacillus polymyxa,4,240 with extra- and intra-cellular lyase of Erwinia carotovora,241 with extracellular enzyme of Xanthomonas campestris,23S and with lyase produced by Bacteroides ruminicola242 isolated from the rumen fluid of sheep.243... 

Bacillus polymyxa in a hydrogen atmosphere reduced (R,S)-acetoin to erythro- and /Areo-butane-l,3-diol in 100% yield [910], and Saccharomyces cerevisiae converted 3,3-dimethyl-l-hydroxybutan-2-one to (—)-R-3,3-dimethylbutane-l,2-diol in 66% yield [911]. 

Polymyxines Polymyxines are a gronp of related polypeptide antibiotics that are produced by sporo-forming soil bacteria Bacillus polymyxa and B. circulans, and they differ in amino acid content. Five different polymyxines have been identified—polymyxines A, B, C, D, and E, which differ in the amino acid content and are differentiated by additional letter notations and names— polymyxine B (aerosporin) and polymyxine E (colistin). It is known that in the process of development, some strains of B. polymyxa only form polymyxines A and C, and others synthesize polymyxines B and D. Polymyxine M was later isolated, a snlfomethyl derivative of polymyxine E. 

Similar approaches to cloning of bacterial xylanases have been used for genes from Clostridium acetobutylicum (30), Bacillus polymyxa (31), Bacteroides succinogenes (32), Clostridium thermocellum (33) and Pseudomonas fluorescens subsp. cellulosa (34). In each case the xylanases were predominantly located intracellularly and the levels of xylanases produced from cloned systems were, in general, very low in comparison to yeast and fungal systems. A comparison of the production yields and extent of extracellular production for various cloned xylanase genes is found in Table... 

The polymyxins are a group of antibiotics produced by Bacillus polymyxa. Polymyxin B (Aerosporin) and co-Ustin (polymyxin E, Coly-Mycin) are used in the treatment of bacterial diseases. 

Paulus, H. Gray, E. Multivalent feedback inhibition of aspartokinase in Bacillus polymyxa. I. Kinetic studies. J. Biol. Chem., 242, 4980-4986 (1967)... 

Bacillus polymyxa -inhibited by sorbates [SORBIC ACID] (Vol 22)... 

Colistin (COL) is a multicomponent antibiotic (polymyxins E) that is produced by strains of inverse Bacillus polymyxa. It consists of a mixture of several closely related decapeptides with a general structure composed of a cyclic heptapeptide moiety and a side chain acetylated at the N-terminus by a fatty acid. Up to 13 different components have been identified. The two main components of colistin are polymyxins El and E2 they include the same amino acids but a different fatty acid (216). A selective and sensitive HPLC method was developed for the determination of COL residues in milk and four bovine tissues (muscle, liver, kidney, and fat). The sample pretreatment consists of protein precipitation with trichloracetic acid (TCA), solid-phase purification on Cl 8 SPE cartridges, and precolumn derivatization of colistin with o-phthalaldehyde and 2-mercaptoethanol in borate buffer (pH 10.5). The last step was performed automatically, and the resulting reaction mixture was injected into a switching HPLC system including a precolumn and the reversed-phase analytical column. Fluorescence detection was used. The structural study of El and E2 derivatives was carried out by HPLC coupled with an electrospray MS. Recoveries from the preseparation procedure were higher than 60%. 

Bacillus brevis Aspergillus niger Bacillus subtilis j Bacillus polymyxa l Bacillus brevis i Streptomyces fulrissimus... 

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. 

Bacterium Bacillus polymyxa Nutrient medium Corn meal... 

Polymyxin B Bacillus polymyxa R-Dab-Thr-Dab-Dab-Dab-(D) Phe-Leu-Dab-Dab-Thr (Dab is diaminobutyric acid) Cyclic lipopeptide 1.8 26 (59-61)... 

Dispase is a neutral protease from Bacillus polymyxa available from Boehringer Corp. Ltd. It is particularly suitable for disaggregation of animal tissues, which seldom suffer from prolonged treatment. It is available alone, or mixed with collagenase. It requires Ca2+ for activity and its action is readily neutralised by EDTA. 

Maltose (3-amylases are primarily found in plants and have been isolated from sweet potatoes,27 soybeans,28 barley29 and wheat.30 Maltose (3-amylases are also elaborated by bacteria, e.g. by Bacillus polymyxa,31 B. megaterium,32 B. cereus33 and Pseudomonas sp. BQ6.34 These (3-amylases all produce (3-maltose and a high molecular weight (3-limit dextrin. The limit dextrins result when the enzyme reaches an a-(l—>-6) branch linkage, which it cannot pass. Approximately half of an amylopectin molecule is converted to (3-maltose the remaining half is the (3-limit dextrin. 

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