Bacteria hydrolytic enzymes

Brief notes are added on phosphorofluoridates even though their destruction by microbial activity— though clearly possible—is limited by their toxicity to the requisite microorganisms. One of the motivations for their inclusion is the fact that the hydrolytic enzyme(s) responsible for defluorination—organophosphorus acid anhydrase (OPA)—is widespread, and is found in a number of bacteria (Landis and DeFrank 1990). The microbial hydrolysis of organophosphorus pesticides and cholinesterase inhibitors is accomplished by several distinct enzymes, which are collectively termed organophosphorus acid anhydrases (OPAs). These have been reviewed (DeFrank 1991), so that only a few additional comments are necessary. 

The decrease of peak numbers was observed, when the spectra of the same amounts of fresh (12 weeks old) and aged (9 months old) mortars were compared. This decrease might be caused by activity of ubiquitous microorganisms that live on the mortar surfaces in biofilms. Especially in mild climate conditions, algae and cyanobacteria [35] can appear here moulds (Aspergillus, Penicillium, Fusarium, Mucor) [36] and bacteria (Arthrobacter Bacillus, Micrococcus, Staphylococcus) [37,38] have been discovered as well. The microorganisms secrete various hydrolytic enzymes that can decompose the organic additives, namely proteins, and make their sample identification less sensitive... 

Although hydrolytic enzymes, esterases and amidases, are named after their major substrates, the same enzyme can often hydrolyze esters, thioesters, and amides therefore, the differentiation between esterases and amidases is sometimes artificial. The highest hydrolytic activity is in the liver, but the enzyme pseudocholinesterase is found in the serum. Gut bacteria also contain hydrolytic enzymes. 

The dried bacteria also contain invertase and this hydrolytic enzyme competes with the sucrose phosphorylase for sucrose. However, it is possible to eliminate most of the invertase from the bacterial preparations by several precipitations with ammonium sulfate. Using a partially purified sucrose phosphorylase preparation and a mixture of... 

Enzymes that perform the same catalytic function are known as homologous enzymes and fall into two classes. Heteroenzymes are derived from different sources and although they catalyse the same reaction they show different physical and kinetic characteristics. The hydrolytic enzyme a-amylase (EC 3.2.1.1) is found in the pancreatic secretion in man and is different from the enzymes of the same name which are derived from bacteria or malt. Iso-enzymes, sometimes referred to as isozymes, are different molecular forms of the same enzyme and are found in the same animal or organism although they often show a pattern of distribution between tissues. 

Corpe, W.A. and Winters, H., 1972. Hydrolytic enzymes of some periphytic marine bacteria. Can. 3. Microbiol., 18 1483-1490. 

Hydrolytic Reactions. Many pesticides possess bonds that are susceptible to hydrolytic attack. These reactions are most easily characterized according to the type of bond hydrolyzed carboxjlic acid ester, carbamate, oiganophosphate, urea, or chlorine (hydrodechlorination). In many instances the specific hydrolytic enzymes have been purified and characterized and the genes encoding for the enzymes isolated and cloned. It is commonly observed that there are multiple forms of the enzymes catalyzing a particular hydrolytic reaction, which suggests that these catalytic functions have evolved independendy in different bacteria (19). 

These hydrolytic enzymes—which take their name from the fact that the degradation products are sugars in the a-D configuration-are found in mammals, higher plants, fungi, bacteria, and Crustacea. It is now appreciated that both the properties and the detailed action pattern of an alpha-amylase depend on the source of the enzyme. 

Pantothenic add levels in foods and body fluids can easily be measured by microbiological assays. Lactic acid bacteria are used as the test organism. Where measurement of ihe vitamin occurring as coenzyme A is desired, the coenzyme must first be treated virlth hydrolytic enzymes to liberate the pantothenic acid prior to the microbiological assay... 

The cell walls of Gram-positive bacteria, including the pathogens S. aureus. Bacillus anthracis. Streptococcus pneumoniae, and Enterococcus faecalis contain thick layers of peptidoglycan. The peptidoglycan layers serve as both a protective barrier and as a scaffold for the attachment of secondary cell wall polymers and surface proteins. Surface proteins include hydrolytic enzymes involved in peptidoglycan turnover, as well as structures such as pili... 

After death, cells self-destruct (the process of autolysis) under the influence of hydrolytic enzymes, which, in life, aided the recycling of cellular components. This process makes proteins and other components more readily available to the decomposers. Bacteria and fungi preferentially remove the more labile components from detritus and the residue becomes increasingly refract-ory. Much of the soluble product of the microbial breakdown of organic matter diffuses upward within pore waters to the sediment—water interface and is returned to the water column. Bacteria are important in all environments, but fungi are relatively... 

More than 90% of enzymes are produced by fermentation by microorganisms, which are used to prepare industrial and special use enzymes. Prokaryotic cells and eukaryotic cells can be easily grown in culture, and the technology of scale-up is well established on an industrial scale. Various kinds of fungi, bacteria and yeast have been screened for the production of special enzymes. Extracellular enzymes, for instance hydrolytic enzymes, are secreted into liquid and solid culture and are relatively stable in cultivation media. 

Xylanases (1,4-3-D-xylan xylanohydrolases, EC 3.2.1.8) are hydrolytic enzymes that catalyze the endohydrolysis of the P-1,4 backbone in xylan, the main polysaccharide of the hemicellulose fraction in plant cell walls [1]. Endoxylanases are reported to be produced mainly by microorganisms, including several species of fungi and bacteria [2-4]. 

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