Enzymes producing

An electrode that responds to the concentration of a substrate by reacting the substrate with an immobilized enzyme, producing an ion that can be monitored with an ion-selective electrode. 

Potcntiomctric Biosensors Potentiometric electrodes for the analysis of molecules of biochemical importance can be constructed in a fashion similar to that used for gas-sensing electrodes. The most common class of potentiometric biosensors are the so-called enzyme electrodes, in which an enzyme is trapped or immobilized at the surface of an ion-selective electrode. Reaction of the analyte with the enzyme produces a product whose concentration is monitored by the ion-selective electrode. Potentiometric biosensors have also been designed around other biologically active species, including antibodies, bacterial particles, tissue, and hormone receptors. 

A.spergilli. The filamentous fungi also include a number of well-known enzyme producers. Among these, was used as a host for Hpase, the first... 

The I I cleaning procedures as a whole, compared with household laundering, are characterized by huge variations in the composition of the soils, types of surface to which they adhere, cleaning time available, etc. The optimum choice of enzyme type and dosage level normally has to be established through a cooperation between the customer (end user), manufacturer of the detergent, and enzyme producer. 

Polyunsaturated fatty acids pose a slightly more complicated situation for the cell. Consider, for example, the case of linoleic acid shown in Figure 24.24. As with oleic acid, /3-oxidation proceeds through three cycles, and enoyl-CoA isomerase converts the cA-A double bond to a trans-b double bond to permit one more round of /3-oxidation. What results this time, however, is a cA-A enoyl-CoA, which is converted normally by acyl-CoA dehydrogenase to a trans-b, cis-b species. This, however, is a poor substrate for the enoyl-CoA hydratase. This problem is solved by 2,4-dienoyl-CoA reductase, the product of which depends on the organism. The mammalian form of this enzyme produces a trans-b enoyl product, as shown in Figure 24.24, which can be converted by an enoyl-CoA isomerase to the trans-b enoyl-CoA, which can then proceed normally through the /3-oxidation pathway. Escherichia coli possesses a... 

How many of the 14 NADPH needed to form one palmitate (Eq. 25.1) can be made in this way The answer depends on the status of malate. Every citrate entering the cytosol produces one acetyl-CoA and one malate (Figure 25.1). Every malate oxidized by malic enzyme produces one NADPH, at the expense of a decarboxylation to pyruvate. Thus, when malate is oxidized, one NADPH is produced for every acetyl-CoA. Conversion of 8 acetyl-CoA units to one palmitate would then be accompanied by production of 8 NADPH. (The other 6 NADPH required [Eq. 25.1] would be provided by the pentose phosphate pathway.) On the other hand, for every malate returned to the mitochondria, one NADPH fewer is produced. 

Epoxides are found in thousands of biological molecules and constitute vital functional entities. They can impart localized structural rigidity, confer cytotoxicity through their role as alkylating agents, or act as reactive intermediates in complex synthetic sequences. The widespread occurrence of epoxides is contrasted by only a handful of aziridines that are known to date. In this chapter we would like to introduce the different mechanisms by which enzymes produce epoxides. 

The most commonly used source of penicillin V acylase is the fungus Bovista plumbia. Incubation of phenoxymethyl penicillin (penicillin V) with this enzyme produces a yield of about 90-92% 6-APA. 

The functioning of enzymes produces phenomena driving the processes which impart life to an organic system. The principal source of information about an enzyme-catalyzed reaction has been from analyses of the changes produced in concentrations of substrates and products. These observations have led to the construction of models invoking intermediate complexes of ingredients with the enzyme. One example is the Michaelis-Menten model, postulating an... 

Biocatalysts these are essential for life and play a vital role in most processes occurring within the body as well as in plants. In the laboratory biocatalysts are usually natural enzymes or enzymes produced in situ from whole cells. They offer the possibility of carrying out many difficult transformations under mild conditions and are especially valuable for producing enantiomerically pure materials. Their huge potential is currently largely untapped, partially due to the time and expense of isolating and screening enzymes. 

Besides the capacity of CRTI to introduce all four double bonds in the conversion of phytoene to lycopene, the enzyme produces different geometric isomers than does PDS/ZDS (see graphic, side-by-side comparison in Fraser and Bramley ). CRTI produces all-trans isomers. Studies that have examined the function of the paired plant desaturases acting together, from Arabidopsis, and from maize and from... 

Larena, I. et al.. Biocontrol of Fusarium and Verticillium wilt of tomato by Penicillium oxalicum under greenhouse and field conditions, J. Phytopath, 151, 507, 2003. Hashem, A.M., Purification and properties of a milk-clotting enzyme produced by Penicillium oxalicum, Biores. Technol, 75, 219, 2000. 

A Pstl-HinA (1.2 kbp) fragment was subcloned in pUC19. The enzyme produced by the E. coli transformant was purified fo homogeneify and shown to be identical to that of the original strain. Both enzymes had the same enzymological properties and N-terminal amino acid sequences. ... 

Ried, J. L. and Collmer, A. (1986). Comparison of pectic enzymes produced by Erwinia chrysanthemi, Erwinia carotovora subsp. carotovora, and Erwinia carotovora subsp. atroseptica. AppI Environ Microbiol 52, 305-310. 

Gist-Brocades as enzymes producer is associated to european fruit juice producers, INRA and Wageningen University Professor Voragen, in a Eureka project dealing with "Fruits liquefaction with specific enzymes". 

The lack inhibition of enzymatic activity by glucose still leaves the PG enzymes produced on a constitutive basis free to hydrolyze their substrate. 

Two characteristics of the lyase that we have purified may be significant. First, the small molecular size of the protein may confer it a high mobility that could be helpful to its movement through host cell walls. In second place, it is an endo-type enzyme, fact that has been considered essential for maceration of plant tissues [35]. In this sense it is noteworthy that between the battery of pectic enzymes produced by FORL, this pectin lyase is the only protein that behaves as an endo-type. 

Enzymes produced by parental (CLIOO) and mutant (CTl) strains cultured on citrus pectin... 

Ratnatilleke A, JW Vrijbloed, JA Robinson (1999) Cloning and sequencing of the coenzyme B,2-binding domain of isobutyryl-CoA mutase from Streptomyces cinnamonensis. Reconstitution of mutase activity and characterization of the recombinant enzyme produced in Escherichia coli. J Biol Chem 274 31679-31685. 

The last enzymatic step of the cannabinoid pathway is the production of THCA (3.5), CBDA (3.4) or CBGA (3.6). The compounds are produced by three different enzymes. The first enzyme produces the major psychoactive compound of cannabis, THCA [21,38] the second and third are responsible for the production of CBDA [39] and CBGA [40], respectively. All of these enzymes belong to the enzyme group oxidoreductases [38-41], which means that they are able to use an electron donor for the transfer of an electron to an acceptor. From these enzymes only the THCA and the CBDA synthase gene sequence have been elucidated. Their product also represents the highest constituent in most C. sativa strains. 

---