Microbial sources

Microbial sources Marinactan Flavobacterium uliginosum solid sarcome 180 in mice [31] 

Vegetable TSPS Camelia sinensis (tea) K562 cells (human myelogenous leukemia) in-vivo [40] 

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Enzymatic Method. L-Amino acids can be produced by the enzymatic hydrolysis of chemically synthesized DL-amino acids or derivatives such as esters, hydantoins, carbamates, amides, and acylates (24). The enzyme which hydrolyzes the L-isomer specifically has been found in microbial sources. The resulting L-amino acid is isolated through routine chemical or physical processes. The D-isomer which remains unchanged is racemized chemically or enzymatically and the process is recycled. Conversely, enzymes which act specifically on D-isomers have been found. Thus various D-amino acids have been... 

A microbial source for a food enzyme must be nonpathogenic and nontoxicogenic. Manufacturers of microbial food enzymes have always selected their production microorganisms from the safe end of the spectmm of available sources. Consequendy, a few species have acquired a record of safe use as sources of a wide variety of food enzymes. 

Enzyme preparations from liver or microbial sources were reported to show rather high substrate specificity [76] for the natural phosphorylated acceptor d-(18) but, at much reduced reaction rates, offer a rather broad substrate tolerance for polar, short-chain aldehydes [77-79]. Simple aliphatic or aromatic aldehydes are not converted. Therefore, the aldolase from Escherichia coli has been mutated for improved acceptance of nonphosphorylated and enantiomeric substrates toward facilitated enzymatic syntheses ofboth d- and t-sugars [80,81]. High stereoselectivity of the wild-type enzyme has been utilized in the preparation of compounds (23) / (24) and in a two-step enzymatic synthesis of (22), the N-terminal amino acid portion of nikkomycin antibiotics (Figure 10.12) [82]. 

Although there is no doubt as to the importance of mycorrhizae in nutrient absorption, reviews on ion uptake have generally not considered it. Hatling et al. (143) made this same point more than 10 years ago. In addition, although phenolic acids inhibit phosphate (144, 145) and potassium (146) uptake, no work has examined the effects of these compounds on nutrient absorption of mycorrhizal associations. Since soil microorganisms produce the bulk of the volatile compounds emitted from soil, which are known to inhibit or stimulate fungal development (147-148), this group of compounds from microbial sources should receive more attention. 

Unless the last-mentioned product is removed by the inclusion of catalase, the oxoacid is liable to react further, undergoing oxidative decarboxylation to the carboxylic acid. An attractive feature of this group of enzymes in the present context is that there exist readily available representatives of both enantiospecificities. The well-studied and commercially available AAOs from vertebrate sources, such as l-AAO from snake venom and D-AAO from pig kidney, are expensive, however, and are increasingly being replaced by enzymes from microbial sources. 

Over the past 20 years, the S. aureus SEs and TSST-1 have been called superantigens . This term was first proposed in the late 1980s by Marrack and Kappler to describe microbial (bacterial or viral) proteins that activate large numbers of specific T cells versus conventional antigens. Table 3 lists the various superantigens, and their diverse microbial sources, known to date. Ey definition, interactions of superantigens with cells of the... 

Proteases are the most extensively used enzymes in the food industry, where they act to improve the quality, stability, and solubility of foods. Some of the attributes of enzymes which make them useful in industrial operations include the following 1) They are derived from plants, animal, and microbial sources and are invariably nontoxic substances that are able catalyze specific reactions 2) they are active at very low concentrations under mild conditions of temperature and pH where undesirable side reactions are minimized and 3) they can be inactivated after a desired effect has been achieved. Proteases from plant, animal, and microbial sources find extensive use as food processing aids.(32) Some of the applications of proteases in the food industry are summarized in Table I. 

The greatest variety of industrial enzymes are presently derived from microbial sources, with a lesser diversity coming from plant and animal sources 34), Enzymes derived from plant sources and which are used extensively in the food industry include papain, bromelain, ficin, and amylases. Animal enzymes of economic importance include trypsins, lipases, and gastric proteases. 

Bacteria represent a promising source for the production of industrial enzymes. Bacterial cellulases are an especialfy interesting case in point. Many thermophilic bacterial species produce cellulases that are stable and active at high temperature, resistant to proteolytic attack, and stable to mechanical and chemical denaturation. However, cellulase productivities in bacteria are notoriously low compared to other microbial sources. In this paper bacterial enzyme production systems will be discussed with a focus on comparisons of the productivities of known bacterial cellulase producers. In an attempt to draw conclusions concerning the regulation of cellulase synthesis in bacterial systems, a tentative model for regulation in Acidothennus cellulofyticus has been developed. 

Feling RH, Buchanan GO, Mincer TJ, Kauffman CA, Jensen PR, Fenical W. (2003) Salinosporamide A A highly cytotoxic proteasome inhibitor from a novel microbial source, a marine bacterium of the new genus salinospora. Angew Chem Int Ed Engl 42 355-357. 

Traditionally, the majority of the studies in this area have emphasized the analysis of microorganisms, in particular of soil actinomycetes, as the most relevant source of potential herbicide agents. The plant kingdom, however, has also been explored for the discovery of new herbicides. So far, bialaphos, originally isolated from different Streptomyces strains, is the only commercial herbicide derived from a microbial source. On the other hand, cymethylin, an analog of the mono terpenoid 1,8-cineole, as well as... 

Harwood, V. J., Wiggins, B., Hagedorn, C., Ellender, R. D., Gooch, J., Kern, J., Samadpour, M., Chapman, A. C. H., Robinson, B. J., and Thompson, B. C. (2003). Phenotypic library-based microbial source tracking methods Efficacy in the California collaborative study. J. Water Health 1,153-166. 

Myoda, S. P., Carson, C. A., Fuhrmann, J. J., Hahm, B.-K., Hartel, P. G., Yampara-Iquise, H., Johnson, L.-A., Kuntz, R. L., Nakatsu, C. H., Sadowsky, M. J., and Samadpour, M. (2003). Comparison of genotypic-based microbial source tracking methods requiring a host origin database. J. Water Health 1,167-180. 

Nayak, R. and Stewart-King, T. (2008). Molecular epidemiological analysis and microbial source tracking of Salmonella enterica serovars in a preharvest turkey production environment. Foodborne Pathog. Dis. 5,115-126. 

Stoeckel, D. M. and Harwood, V. J. (2007). Performance, design, and analysis in microbial source tracking studies. Appl. Environ. Microbiol. 73, 2405-2415. 

The microbial sources of penicillin amidases/acylases required for side-chain removal were found and were quickly commercialised as whole-cell biocatalysts. 

Many microbial sources of enzymes suitable for converting them into L-phenylalanine... 

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